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-rw-r--r--kernel/acct.c6
-rw-r--r--kernel/async.c159
-rw-r--r--kernel/audit.c40
-rw-r--r--kernel/audit_tree.c26
-rw-r--r--kernel/audit_watch.c2
-rw-r--r--kernel/auditfilter.c1
-rw-r--r--kernel/auditsc.c20
-rw-r--r--kernel/compat.c23
-rw-r--r--kernel/context_tracking.c114
-rw-r--r--kernel/cpu.c6
-rw-r--r--kernel/debug/kdb/kdb_main.c2
-rw-r--r--kernel/delayacct.c7
-rw-r--r--kernel/events/core.c25
-rw-r--r--kernel/events/hw_breakpoint.c2
-rw-r--r--kernel/events/uprobes.c466
-rw-r--r--kernel/exit.c10
-rw-r--r--kernel/fork.c12
-rw-r--r--kernel/futex.c1
-rw-r--r--kernel/hrtimer.c38
-rw-r--r--kernel/irq/chip.c30
-rw-r--r--kernel/irq/manage.c3
-rw-r--r--kernel/irq/spurious.c7
-rw-r--r--kernel/irq_work.c150
-rw-r--r--kernel/kmod.c9
-rw-r--r--kernel/kprobes.c31
-rw-r--r--kernel/module.c181
-rw-r--r--kernel/mutex.c1
-rw-r--r--kernel/pid.c2
-rw-r--r--kernel/posix-cpu-timers.c51
-rw-r--r--kernel/posix-timers.c2
-rw-r--r--kernel/printk.c50
-rw-r--r--kernel/profile.c24
-rw-r--r--kernel/ptrace.c80
-rw-r--r--kernel/rcu.h7
-rw-r--r--kernel/rcupdate.c60
-rw-r--r--kernel/rcutiny.c8
-rw-r--r--kernel/rcutiny_plugin.h56
-rw-r--r--kernel/rcutorture.c66
-rw-r--r--kernel/rcutree.c260
-rw-r--r--kernel/rcutree.h11
-rw-r--r--kernel/rcutree_plugin.h13
-rw-r--r--kernel/rtmutex-debug.c1
-rw-r--r--kernel/rtmutex-tester.c1
-rw-r--r--kernel/rtmutex.c1
-rw-r--r--kernel/rwsem.c10
-rw-r--r--kernel/sched/core.c27
-rw-r--r--kernel/sched/cpupri.c2
-rw-r--r--kernel/sched/cputime.c314
-rw-r--r--kernel/sched/debug.c4
-rw-r--r--kernel/sched/fair.c29
-rw-r--r--kernel/sched/rt.c28
-rw-r--r--kernel/sched/sched.h2
-rw-r--r--kernel/signal.c45
-rw-r--r--kernel/smp.c13
-rw-r--r--kernel/smpboot.c5
-rw-r--r--kernel/softirq.c6
-rw-r--r--kernel/srcu.c37
-rw-r--r--kernel/stop_machine.c156
-rw-r--r--kernel/sysctl.c8
-rw-r--r--kernel/time.c8
-rw-r--r--kernel/time/Kconfig9
-rw-r--r--kernel/time/ntp.c22
-rw-r--r--kernel/time/tick-broadcast.c38
-rw-r--r--kernel/time/tick-sched.c12
-rw-r--r--kernel/time/timekeeping.c45
-rw-r--r--kernel/timeconst.pl6
-rw-r--r--kernel/timer.c2
-rw-r--r--kernel/trace/Kconfig18
-rw-r--r--kernel/trace/blktrace.c2
-rw-r--r--kernel/trace/ftrace.c90
-rw-r--r--kernel/trace/ring_buffer.c108
-rw-r--r--kernel/trace/trace.c270
-rw-r--r--kernel/trace/trace.h134
-rw-r--r--kernel/trace/trace_clock.c5
-rw-r--r--kernel/trace/trace_events.c1
-rw-r--r--kernel/trace/trace_functions.c61
-rw-r--r--kernel/trace/trace_functions_graph.c68
-rw-r--r--kernel/trace/trace_probe.h1
-rw-r--r--kernel/trace/trace_sched_wakeup.c2
-rw-r--r--kernel/trace/trace_selftest.c21
-rw-r--r--kernel/trace/trace_syscalls.c18
-rw-r--r--kernel/trace/trace_uprobe.c217
-rw-r--r--kernel/tsacct.c44
-rw-r--r--kernel/watchdog.c1
-rw-r--r--kernel/workqueue.c1530
-rw-r--r--kernel/workqueue_internal.h65
-rw-r--r--kernel/workqueue_sched.h9
87 files changed, 3505 insertions, 2053 deletions
diff --git a/kernel/acct.c b/kernel/acct.c
index 051e071a06e..e8b1627ab9c 100644
--- a/kernel/acct.c
+++ b/kernel/acct.c
@@ -566,6 +566,7 @@ out:
void acct_collect(long exitcode, int group_dead)
{
struct pacct_struct *pacct = &current->signal->pacct;
+ cputime_t utime, stime;
unsigned long vsize = 0;
if (group_dead && current->mm) {
@@ -593,8 +594,9 @@ void acct_collect(long exitcode, int group_dead)
pacct->ac_flag |= ACORE;
if (current->flags & PF_SIGNALED)
pacct->ac_flag |= AXSIG;
- pacct->ac_utime += current->utime;
- pacct->ac_stime += current->stime;
+ task_cputime(current, &utime, &stime);
+ pacct->ac_utime += utime;
+ pacct->ac_stime += stime;
pacct->ac_minflt += current->min_flt;
pacct->ac_majflt += current->maj_flt;
spin_unlock_irq(&current->sighand->siglock);
diff --git a/kernel/async.c b/kernel/async.c
index 9d311838485..8ddee2c3e5b 100644
--- a/kernel/async.c
+++ b/kernel/async.c
@@ -57,56 +57,52 @@ asynchronous and synchronous parts of the kernel.
#include <linux/slab.h>
#include <linux/workqueue.h>
+#include "workqueue_internal.h"
+
static async_cookie_t next_cookie = 1;
-#define MAX_WORK 32768
+#define MAX_WORK 32768
+#define ASYNC_COOKIE_MAX ULLONG_MAX /* infinity cookie */
-static LIST_HEAD(async_pending);
-static ASYNC_DOMAIN(async_running);
-static LIST_HEAD(async_domains);
+static LIST_HEAD(async_global_pending); /* pending from all registered doms */
+static ASYNC_DOMAIN(async_dfl_domain);
static DEFINE_SPINLOCK(async_lock);
-static DEFINE_MUTEX(async_register_mutex);
struct async_entry {
- struct list_head list;
+ struct list_head domain_list;
+ struct list_head global_list;
struct work_struct work;
async_cookie_t cookie;
async_func_ptr *func;
void *data;
- struct async_domain *running;
+ struct async_domain *domain;
};
static DECLARE_WAIT_QUEUE_HEAD(async_done);
static atomic_t entry_count;
-
-/*
- * MUST be called with the lock held!
- */
-static async_cookie_t __lowest_in_progress(struct async_domain *running)
+static async_cookie_t lowest_in_progress(struct async_domain *domain)
{
- struct async_entry *entry;
-
- if (!list_empty(&running->domain)) {
- entry = list_first_entry(&running->domain, typeof(*entry), list);
- return entry->cookie;
- }
+ struct async_entry *first = NULL;
+ async_cookie_t ret = ASYNC_COOKIE_MAX;
+ unsigned long flags;
- list_for_each_entry(entry, &async_pending, list)
- if (entry->running == running)
- return entry->cookie;
+ spin_lock_irqsave(&async_lock, flags);
- return next_cookie; /* "infinity" value */
-}
+ if (domain) {
+ if (!list_empty(&domain->pending))
+ first = list_first_entry(&domain->pending,
+ struct async_entry, domain_list);
+ } else {
+ if (!list_empty(&async_global_pending))
+ first = list_first_entry(&async_global_pending,
+ struct async_entry, global_list);
+ }
-static async_cookie_t lowest_in_progress(struct async_domain *running)
-{
- unsigned long flags;
- async_cookie_t ret;
+ if (first)
+ ret = first->cookie;
- spin_lock_irqsave(&async_lock, flags);
- ret = __lowest_in_progress(running);
spin_unlock_irqrestore(&async_lock, flags);
return ret;
}
@@ -120,14 +116,8 @@ static void async_run_entry_fn(struct work_struct *work)
container_of(work, struct async_entry, work);
unsigned long flags;
ktime_t uninitialized_var(calltime), delta, rettime;
- struct async_domain *running = entry->running;
- /* 1) move self to the running queue */
- spin_lock_irqsave(&async_lock, flags);
- list_move_tail(&entry->list, &running->domain);
- spin_unlock_irqrestore(&async_lock, flags);
-
- /* 2) run (and print duration) */
+ /* 1) run (and print duration) */
if (initcall_debug && system_state == SYSTEM_BOOTING) {
printk(KERN_DEBUG "calling %lli_%pF @ %i\n",
(long long)entry->cookie,
@@ -144,23 +134,22 @@ static void async_run_entry_fn(struct work_struct *work)
(long long)ktime_to_ns(delta) >> 10);
}
- /* 3) remove self from the running queue */
+ /* 2) remove self from the pending queues */
spin_lock_irqsave(&async_lock, flags);
- list_del(&entry->list);
- if (running->registered && --running->count == 0)
- list_del_init(&running->node);
+ list_del_init(&entry->domain_list);
+ list_del_init(&entry->global_list);
- /* 4) free the entry */
+ /* 3) free the entry */
kfree(entry);
atomic_dec(&entry_count);
spin_unlock_irqrestore(&async_lock, flags);
- /* 5) wake up any waiters */
+ /* 4) wake up any waiters */
wake_up(&async_done);
}
-static async_cookie_t __async_schedule(async_func_ptr *ptr, void *data, struct async_domain *running)
+static async_cookie_t __async_schedule(async_func_ptr *ptr, void *data, struct async_domain *domain)
{
struct async_entry *entry;
unsigned long flags;
@@ -183,19 +172,28 @@ static async_cookie_t __async_schedule(async_func_ptr *ptr, void *data, struct a
ptr(data, newcookie);
return newcookie;
}
+ INIT_LIST_HEAD(&entry->domain_list);
+ INIT_LIST_HEAD(&entry->global_list);
INIT_WORK(&entry->work, async_run_entry_fn);
entry->func = ptr;
entry->data = data;
- entry->running = running;
+ entry->domain = domain;
spin_lock_irqsave(&async_lock, flags);
+
+ /* allocate cookie and queue */
newcookie = entry->cookie = next_cookie++;
- list_add_tail(&entry->list, &async_pending);
- if (running->registered && running->count++ == 0)
- list_add_tail(&running->node, &async_domains);
+
+ list_add_tail(&entry->domain_list, &domain->pending);
+ if (domain->registered)
+ list_add_tail(&entry->global_list, &async_global_pending);
+
atomic_inc(&entry_count);
spin_unlock_irqrestore(&async_lock, flags);
+ /* mark that this task has queued an async job, used by module init */
+ current->flags |= PF_USED_ASYNC;
+
/* schedule for execution */
queue_work(system_unbound_wq, &entry->work);
@@ -212,7 +210,7 @@ static async_cookie_t __async_schedule(async_func_ptr *ptr, void *data, struct a
*/
async_cookie_t async_schedule(async_func_ptr *ptr, void *data)
{
- return __async_schedule(ptr, data, &async_running);
+ return __async_schedule(ptr, data, &async_dfl_domain);
}
EXPORT_SYMBOL_GPL(async_schedule);
@@ -220,18 +218,18 @@ EXPORT_SYMBOL_GPL(async_schedule);
* async_schedule_domain - schedule a function for asynchronous execution within a certain domain
* @ptr: function to execute asynchronously
* @data: data pointer to pass to the function
- * @running: running list for the domain
+ * @domain: the domain
*
* Returns an async_cookie_t that may be used for checkpointing later.
- * @running may be used in the async_synchronize_*_domain() functions
- * to wait within a certain synchronization domain rather than globally.
- * A synchronization domain is specified via the running queue @running to use.
- * Note: This function may be called from atomic or non-atomic contexts.
+ * @domain may be used in the async_synchronize_*_domain() functions to
+ * wait within a certain synchronization domain rather than globally. A
+ * synchronization domain is specified via @domain. Note: This function
+ * may be called from atomic or non-atomic contexts.
*/
async_cookie_t async_schedule_domain(async_func_ptr *ptr, void *data,
- struct async_domain *running)
+ struct async_domain *domain)
{
- return __async_schedule(ptr, data, running);
+ return __async_schedule(ptr, data, domain);
}
EXPORT_SYMBOL_GPL(async_schedule_domain);
@@ -242,18 +240,7 @@ EXPORT_SYMBOL_GPL(async_schedule_domain);
*/
void async_synchronize_full(void)
{
- mutex_lock(&async_register_mutex);
- do {
- struct async_domain *domain = NULL;
-
- spin_lock_irq(&async_lock);
- if (!list_empty(&async_domains))
- domain = list_first_entry(&async_domains, typeof(*domain), node);
- spin_unlock_irq(&async_lock);
-
- async_synchronize_cookie_domain(next_cookie, domain);
- } while (!list_empty(&async_domains));
- mutex_unlock(&async_register_mutex);
+ async_synchronize_full_domain(NULL);
}
EXPORT_SYMBOL_GPL(async_synchronize_full);
@@ -268,51 +255,45 @@ EXPORT_SYMBOL_GPL(async_synchronize_full);
*/
void async_unregister_domain(struct async_domain *domain)
{
- mutex_lock(&async_register_mutex);
spin_lock_irq(&async_lock);
- WARN_ON(!domain->registered || !list_empty(&domain->node) ||
- !list_empty(&domain->domain));
+ WARN_ON(!domain->registered || !list_empty(&domain->pending));
domain->registered = 0;
spin_unlock_irq(&async_lock);
- mutex_unlock(&async_register_mutex);
}
EXPORT_SYMBOL_GPL(async_unregister_domain);
/**
* async_synchronize_full_domain - synchronize all asynchronous function within a certain domain
- * @domain: running list to synchronize on
+ * @domain: the domain to synchronize
*
* This function waits until all asynchronous function calls for the
- * synchronization domain specified by the running list @domain have been done.
+ * synchronization domain specified by @domain have been done.
*/
void async_synchronize_full_domain(struct async_domain *domain)
{
- async_synchronize_cookie_domain(next_cookie, domain);
+ async_synchronize_cookie_domain(ASYNC_COOKIE_MAX, domain);
}
EXPORT_SYMBOL_GPL(async_synchronize_full_domain);
/**
* async_synchronize_cookie_domain - synchronize asynchronous function calls within a certain domain with cookie checkpointing
* @cookie: async_cookie_t to use as checkpoint
- * @running: running list to synchronize on
+ * @domain: the domain to synchronize (%NULL for all registered domains)
*
* This function waits until all asynchronous function calls for the
- * synchronization domain specified by running list @running submitted
- * prior to @cookie have been done.
+ * synchronization domain specified by @domain submitted prior to @cookie
+ * have been done.
*/
-void async_synchronize_cookie_domain(async_cookie_t cookie, struct async_domain *running)
+void async_synchronize_cookie_domain(async_cookie_t cookie, struct async_domain *domain)
{
ktime_t uninitialized_var(starttime), delta, endtime;
- if (!running)
- return;
-
if (initcall_debug && system_state == SYSTEM_BOOTING) {
printk(KERN_DEBUG "async_waiting @ %i\n", task_pid_nr(current));
starttime = ktime_get();
}
- wait_event(async_done, lowest_in_progress(running) >= cookie);
+ wait_event(async_done, lowest_in_progress(domain) >= cookie);
if (initcall_debug && system_state == SYSTEM_BOOTING) {
endtime = ktime_get();
@@ -334,6 +315,18 @@ EXPORT_SYMBOL_GPL(async_synchronize_cookie_domain);
*/
void async_synchronize_cookie(async_cookie_t cookie)
{
- async_synchronize_cookie_domain(cookie, &async_running);
+ async_synchronize_cookie_domain(cookie, &async_dfl_domain);
}
EXPORT_SYMBOL_GPL(async_synchronize_cookie);
+
+/**
+ * current_is_async - is %current an async worker task?
+ *
+ * Returns %true if %current is an async worker task.
+ */
+bool current_is_async(void)
+{
+ struct worker *worker = current_wq_worker();
+
+ return worker && worker->current_func == async_run_entry_fn;
+}
diff --git a/kernel/audit.c b/kernel/audit.c
index 40414e9143d..d596e5355f1 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -272,6 +272,8 @@ static int audit_log_config_change(char *function_name, int new, int old,
int rc = 0;
ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
+ if (unlikely(!ab))
+ return rc;
audit_log_format(ab, "%s=%d old=%d auid=%u ses=%u", function_name, new,
old, from_kuid(&init_user_ns, loginuid), sessionid);
if (sid) {
@@ -619,6 +621,8 @@ static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type,
}
*ab = audit_log_start(NULL, GFP_KERNEL, msg_type);
+ if (unlikely(!*ab))
+ return rc;
audit_log_format(*ab, "pid=%d uid=%u auid=%u ses=%u",
task_tgid_vnr(current),
from_kuid(&init_user_ns, current_uid()),
@@ -1097,6 +1101,23 @@ static inline void audit_get_stamp(struct audit_context *ctx,
}
}
+/*
+ * Wait for auditd to drain the queue a little
+ */
+static void wait_for_auditd(unsigned long sleep_time)
+{
+ DECLARE_WAITQUEUE(wait, current);
+ set_current_state(TASK_INTERRUPTIBLE);
+ add_wait_queue(&audit_backlog_wait, &wait);
+
+ if (audit_backlog_limit &&
+ skb_queue_len(&audit_skb_queue) > audit_backlog_limit)
+ schedule_timeout(sleep_time);
+
+ __set_current_state(TASK_RUNNING);
+ remove_wait_queue(&audit_backlog_wait, &wait);
+}
+
/* Obtain an audit buffer. This routine does locking to obtain the
* audit buffer, but then no locking is required for calls to
* audit_log_*format. If the tsk is a task that is currently in a
@@ -1142,20 +1163,13 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask,
while (audit_backlog_limit
&& skb_queue_len(&audit_skb_queue) > audit_backlog_limit + reserve) {
- if (gfp_mask & __GFP_WAIT && audit_backlog_wait_time
- && time_before(jiffies, timeout_start + audit_backlog_wait_time)) {
+ if (gfp_mask & __GFP_WAIT && audit_backlog_wait_time) {
+ unsigned long sleep_time;
- /* Wait for auditd to drain the queue a little */
- DECLARE_WAITQUEUE(wait, current);
- set_current_state(TASK_INTERRUPTIBLE);
- add_wait_queue(&audit_backlog_wait, &wait);
-
- if (audit_backlog_limit &&
- skb_queue_len(&audit_skb_queue) > audit_backlog_limit)
- schedule_timeout(timeout_start + audit_backlog_wait_time - jiffies);
-
- __set_current_state(TASK_RUNNING);
- remove_wait_queue(&audit_backlog_wait, &wait);
+ sleep_time = timeout_start + audit_backlog_wait_time -
+ jiffies;
+ if ((long)sleep_time > 0)
+ wait_for_auditd(sleep_time);
continue;
}
if (audit_rate_check() && printk_ratelimit())
diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c
index e81175ef25f..642a89c4f3d 100644
--- a/kernel/audit_tree.c
+++ b/kernel/audit_tree.c
@@ -449,11 +449,26 @@ static int tag_chunk(struct inode *inode, struct audit_tree *tree)
return 0;
}
+static void audit_log_remove_rule(struct audit_krule *rule)
+{
+ struct audit_buffer *ab;
+
+ ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
+ if (unlikely(!ab))
+ return;
+ audit_log_format(ab, "op=");
+ audit_log_string(ab, "remove rule");
+ audit_log_format(ab, " dir=");
+ audit_log_untrustedstring(ab, rule->tree->pathname);
+ audit_log_key(ab, rule->filterkey);
+ audit_log_format(ab, " list=%d res=1", rule->listnr);
+ audit_log_end(ab);
+}
+
static void kill_rules(struct audit_tree *tree)
{
struct audit_krule *rule, *next;
struct audit_entry *entry;
- struct audit_buffer *ab;
list_for_each_entry_safe(rule, next, &tree->rules, rlist) {
entry = container_of(rule, struct audit_entry, rule);
@@ -461,14 +476,7 @@ static void kill_rules(struct audit_tree *tree)
list_del_init(&rule->rlist);
if (rule->tree) {
/* not a half-baked one */
- ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
- audit_log_format(ab, "op=");
- audit_log_string(ab, "remove rule");
- audit_log_format(ab, " dir=");
- audit_log_untrustedstring(ab, rule->tree->pathname);
- audit_log_key(ab, rule->filterkey);
- audit_log_format(ab, " list=%d res=1", rule->listnr);
- audit_log_end(ab);
+ audit_log_remove_rule(rule);
rule->tree = NULL;
list_del_rcu(&entry->list);
list_del(&entry->rule.list);
diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c
index 4a599f699ad..22831c4d369 100644
--- a/kernel/audit_watch.c
+++ b/kernel/audit_watch.c
@@ -240,6 +240,8 @@ static void audit_watch_log_rule_change(struct audit_krule *r, struct audit_watc
if (audit_enabled) {
struct audit_buffer *ab;
ab = audit_log_start(NULL, GFP_NOFS, AUDIT_CONFIG_CHANGE);
+ if (unlikely(!ab))
+ return;
audit_log_format(ab, "auid=%u ses=%u op=",
from_kuid(&init_user_ns, audit_get_loginuid(current)),
audit_get_sessionid(current));
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index 7f19f23d38a..f9fc54bbe06 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -1144,7 +1144,6 @@ static void audit_log_rule_change(kuid_t loginuid, u32 sessionid, u32 sid,
* audit_receive_filter - apply all rules to the specified message type
* @type: audit message type
* @pid: target pid for netlink audit messages
- * @uid: target uid for netlink audit messages
* @seq: netlink audit message sequence (serial) number
* @data: payload data
* @datasz: size of payload data
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index e37e6a12c5e..a371f857a0a 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -1464,14 +1464,14 @@ static void show_special(struct audit_context *context, int *call_panic)
audit_log_end(ab);
ab = audit_log_start(context, GFP_KERNEL,
AUDIT_IPC_SET_PERM);
+ if (unlikely(!ab))
+ return;
audit_log_format(ab,
"qbytes=%lx ouid=%u ogid=%u mode=%#ho",
context->ipc.qbytes,
context->ipc.perm_uid,
context->ipc.perm_gid,
context->ipc.perm_mode);
- if (!ab)
- return;
}
break; }
case AUDIT_MQ_OPEN: {
@@ -2675,7 +2675,7 @@ void __audit_mmap_fd(int fd, int flags)
context->type = AUDIT_MMAP;
}
-static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr)
+static void audit_log_task(struct audit_buffer *ab)
{
kuid_t auid, uid;
kgid_t gid;
@@ -2693,6 +2693,11 @@ static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr)
audit_log_task_context(ab);
audit_log_format(ab, " pid=%d comm=", current->pid);
audit_log_untrustedstring(ab, current->comm);
+}
+
+static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr)
+{
+ audit_log_task(ab);
audit_log_format(ab, " reason=");
audit_log_string(ab, reason);
audit_log_format(ab, " sig=%ld", signr);
@@ -2715,6 +2720,8 @@ void audit_core_dumps(long signr)
return;
ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
+ if (unlikely(!ab))
+ return;
audit_log_abend(ab, "memory violation", signr);
audit_log_end(ab);
}
@@ -2723,8 +2730,11 @@ void __audit_seccomp(unsigned long syscall, long signr, int code)
{
struct audit_buffer *ab;
- ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
- audit_log_abend(ab, "seccomp", signr);
+ ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_SECCOMP);
+ if (unlikely(!ab))
+ return;
+ audit_log_task(ab);
+ audit_log_format(ab, " sig=%ld", signr);
audit_log_format(ab, " syscall=%ld", syscall);
audit_log_format(ab, " compat=%d", is_compat_task());
audit_log_format(ab, " ip=0x%lx", KSTK_EIP(current));
diff --git a/kernel/compat.c b/kernel/compat.c
index f6150e92dfc..36700e9e2be 100644
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -535,9 +535,11 @@ asmlinkage long compat_sys_getrusage(int who, struct compat_rusage __user *ru)
return 0;
}
-asmlinkage long
-compat_sys_wait4(compat_pid_t pid, compat_uint_t __user *stat_addr, int options,
- struct compat_rusage __user *ru)
+COMPAT_SYSCALL_DEFINE4(wait4,
+ compat_pid_t, pid,
+ compat_uint_t __user *, stat_addr,
+ int, options,
+ struct compat_rusage __user *, ru)
{
if (!ru) {
return sys_wait4(pid, stat_addr, options, NULL);
@@ -564,9 +566,10 @@ compat_sys_wait4(compat_pid_t pid, compat_uint_t __user *stat_addr, int options,
}
}
-asmlinkage long compat_sys_waitid(int which, compat_pid_t pid,
- struct compat_siginfo __user *uinfo, int options,
- struct compat_rusage __user *uru)
+COMPAT_SYSCALL_DEFINE5(waitid,
+ int, which, compat_pid_t, pid,
+ struct compat_siginfo __user *, uinfo, int, options,
+ struct compat_rusage __user *, uru)
{
siginfo_t info;
struct rusage ru;
@@ -584,7 +587,11 @@ asmlinkage long compat_sys_waitid(int which, compat_pid_t pid,
return ret;
if (uru) {
- ret = put_compat_rusage(&ru, uru);
+ /* sys_waitid() overwrites everything in ru */
+ if (COMPAT_USE_64BIT_TIME)
+ ret = copy_to_user(uru, &ru, sizeof(ru));
+ else
+ ret = put_compat_rusage(&ru, uru);
if (ret)
return ret;
}
@@ -994,7 +1001,7 @@ compat_sys_rt_sigtimedwait (compat_sigset_t __user *uthese,
sigset_from_compat(&s, &s32);
if (uts) {
- if (get_compat_timespec(&t, uts))
+ if (compat_get_timespec(&t, uts))
return -EFAULT;
}
diff --git a/kernel/context_tracking.c b/kernel/context_tracking.c
index e0e07fd5550..65349f07b87 100644
--- a/kernel/context_tracking.c
+++ b/kernel/context_tracking.c
@@ -1,29 +1,41 @@
+/*
+ * Context tracking: Probe on high level context boundaries such as kernel
+ * and userspace. This includes syscalls and exceptions entry/exit.
+ *
+ * This is used by RCU to remove its dependency on the timer tick while a CPU
+ * runs in userspace.
+ *
+ * Started by Frederic Weisbecker:
+ *
+ * Copyright (C) 2012 Red Hat, Inc., Frederic Weisbecker <fweisbec@redhat.com>
+ *
+ * Many thanks to Gilad Ben-Yossef, Paul McKenney, Ingo Molnar, Andrew Morton,
+ * Steven Rostedt, Peter Zijlstra for suggestions and improvements.
+ *
+ */
+
#include <linux/context_tracking.h>
+#include <linux/kvm_host.h>
#include <linux/rcupdate.h>
#include <linux/sched.h>
-#include <linux/percpu.h>
#include <linux/hardirq.h>
+#include <linux/export.h>
-struct context_tracking {
- /*
- * When active is false, hooks are not set to
- * minimize overhead: TIF flags are cleared
- * and calls to user_enter/exit are ignored. This
- * may be further optimized using static keys.
- */
- bool active;
- enum {
- IN_KERNEL = 0,
- IN_USER,
- } state;
-};
-
-static DEFINE_PER_CPU(struct context_tracking, context_tracking) = {
+DEFINE_PER_CPU(struct context_tracking, context_tracking) = {
#ifdef CONFIG_CONTEXT_TRACKING_FORCE
.active = true,
#endif
};
+/**
+ * user_enter - Inform the context tracking that the CPU is going to
+ * enter userspace mode.
+ *
+ * This function must be called right before we switch from the kernel
+ * to userspace, when it's guaranteed the remaining kernel instructions
+ * to execute won't use any RCU read side critical section because this
+ * function sets RCU in extended quiescent state.
+ */
void user_enter(void)
{
unsigned long flags;
@@ -39,40 +51,90 @@ void user_enter(void)
if (in_interrupt())
return;
+ /* Kernel threads aren't supposed to go to userspace */
WARN_ON_ONCE(!current->mm);
local_irq_save(flags);
if (__this_cpu_read(context_tracking.active) &&
__this_cpu_read(context_tracking.state) != IN_USER) {
- __this_cpu_write(context_tracking.state, IN_USER);
+ /*
+ * At this stage, only low level arch entry code remains and
+ * then we'll run in userspace. We can assume there won't be
+ * any RCU read-side critical section until the next call to
+ * user_exit() or rcu_irq_enter(). Let's remove RCU's dependency
+ * on the tick.
+ */
+ vtime_user_enter(current);
rcu_user_enter();
+ __this_cpu_write(context_tracking.state, IN_USER);
}
local_irq_restore(flags);
}
+
+/**
+ * user_exit - Inform the context tracking that the CPU is
+ * exiting userspace mode and entering the kernel.
+ *
+ * This function must be called after we entered the kernel from userspace
+ * before any use of RCU read side critical section. This potentially include
+ * any high level kernel code like syscalls, exceptions, signal handling, etc...
+ *
+ * This call supports re-entrancy. This way it can be called from any exception
+ * handler without needing to know if we came from userspace or not.
+ */
void user_exit(void)
{
unsigned long flags;
- /*
- * Some contexts may involve an exception occuring in an irq,
- * leading to that nesting:
- * rcu_irq_enter() rcu_user_exit() rcu_user_exit() rcu_irq_exit()
- * This would mess up the dyntick_nesting count though. And rcu_irq_*()
- * helpers are enough to protect RCU uses inside the exception. So
- * just return immediately if we detect we are in an IRQ.
- */
if (in_interrupt())
return;
local_irq_save(flags);
if (__this_cpu_read(context_tracking.state) == IN_USER) {
- __this_cpu_write(context_tracking.state, IN_KERNEL);
+ /*
+ * We are going to run code that may use RCU. Inform
+ * RCU core about that (ie: we may need the tick again).
+ */
rcu_user_exit();
+ vtime_user_exit(current);
+ __this_cpu_write(context_tracking.state, IN_KERNEL);
}
local_irq_restore(flags);
}
+void guest_enter(void)
+{
+ if (vtime_accounting_enabled())
+ vtime_guest_enter(current);
+ else
+ __guest_enter();
+}
+EXPORT_SYMBOL_GPL(guest_enter);
+
+void guest_exit(void)
+{
+ if (vtime_accounting_enabled())
+ vtime_guest_exit(current);
+ else
+ __guest_exit();
+}
+EXPORT_SYMBOL_GPL(guest_exit);
+
+
+/**
+ * context_tracking_task_switch - context switch the syscall callbacks
+ * @prev: the task that is being switched out
+ * @next: the task that is being switched in
+ *
+ * The context tracking uses the syscall slow path to implement its user-kernel
+ * boundaries probes on syscalls. This way it doesn't impact the syscall fast
+ * path on CPUs that don't do context tracking.
+ *
+ * But we need to clear the flag on the previous task because it may later
+ * migrate to some CPU that doesn't do the context tracking. As such the TIF
+ * flag may not be desired there.
+ */
void context_tracking_task_switch(struct task_struct *prev,
struct task_struct *next)
{
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 3046a503242..b5e4ab2d427 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -224,11 +224,13 @@ void clear_tasks_mm_cpumask(int cpu)
static inline void check_for_tasks(int cpu)
{
struct task_struct *p;
+ cputime_t utime, stime;
write_lock_irq(&tasklist_lock);
for_each_process(p) {
+ task_cputime(p, &utime, &stime);
if (task_cpu(p) == cpu && p->state == TASK_RUNNING &&
- (p->utime || p->stime))
+ (utime || stime))
printk(KERN_WARNING "Task %s (pid = %d) is on cpu %d "
"(state = %ld, flags = %x)\n",
p->comm, task_pid_nr(p), cpu,
@@ -254,6 +256,8 @@ static int __ref take_cpu_down(void *_param)
return err;
cpu_notify(CPU_DYING | param->mod, param->hcpu);
+ /* Park the stopper thread */
+ kthread_park(current);
return 0;
}
diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index 4d5f8d5612f..8875254120b 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -1970,6 +1970,8 @@ static int kdb_lsmod(int argc, const char **argv)
kdb_printf("Module Size modstruct Used by\n");
list_for_each_entry(mod, kdb_modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
kdb_printf("%-20s%8u 0x%p ", mod->name,
mod->core_size, (void *)mod);
diff --git a/kernel/delayacct.c b/kernel/delayacct.c
index 418b3f7053a..d473988c1d0 100644
--- a/kernel/delayacct.c
+++ b/kernel/delayacct.c
@@ -106,6 +106,7 @@ int __delayacct_add_tsk(struct taskstats *d, struct task_struct *tsk)
unsigned long long t2, t3;
unsigned long flags;
struct timespec ts;
+ cputime_t utime, stime, stimescaled, utimescaled;
/* Though tsk->delays accessed later, early exit avoids
* unnecessary returning of other data
@@ -114,12 +115,14 @@ int __delayacct_add_tsk(struct taskstats *d, struct task_struct *tsk)
goto done;
tmp = (s64)d->cpu_run_real_total;
- cputime_to_timespec(tsk->utime + tsk->stime, &ts);
+ task_cputime(tsk, &utime, &stime);
+ cputime_to_timespec(utime + stime, &ts);
tmp += timespec_to_ns(&ts);
d->cpu_run_real_total = (tmp < (s64)d->cpu_run_real_total) ? 0 : tmp;
tmp = (s64)d->cpu_scaled_run_real_total;
- cputime_to_timespec(tsk->utimescaled + tsk->stimescaled, &ts);
+ task_cputime_scaled(tsk, &utimescaled, &stimescaled);
+ cputime_to_timespec(utimescaled + stimescaled, &ts);
tmp += timespec_to_ns(&ts);
d->cpu_scaled_run_real_total =
(tmp < (s64)d->cpu_scaled_run_real_total) ? 0 : tmp;
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 301079d06f2..5c75791d726 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -908,6 +908,15 @@ list_add_event(struct perf_event *event, struct perf_event_context *ctx)
}
/*
+ * Initialize event state based on the perf_event_attr::disabled.
+ */
+static inline void perf_event__state_init(struct perf_event *event)
+{
+ event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF :
+ PERF_EVENT_STATE_INACTIVE;
+}
+
+/*
* Called at perf_event creation and when events are attached/detached from a
* group.
*/
@@ -6162,11 +6171,14 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
if (task) {
event->attach_state = PERF_ATTACH_TASK;
+
+ if (attr->type == PERF_TYPE_TRACEPOINT)
+ event->hw.tp_target = task;
#ifdef CONFIG_HAVE_HW_BREAKPOINT
/*
* hw_breakpoint is a bit difficult here..
*/
- if (attr->type == PERF_TYPE_BREAKPOINT)
+ else if (attr->type == PERF_TYPE_BREAKPOINT)
event->hw.bp_target = task;
#endif
}
@@ -6179,8 +6191,7 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
event->overflow_handler = overflow_handler;
event->overflow_handler_context = context;
- if (attr->disabled)
- event->state = PERF_EVENT_STATE_OFF;
+ perf_event__state_init(event);
pmu = NULL;
@@ -6609,9 +6620,17 @@ SYSCALL_DEFINE5(perf_event_open,
mutex_lock(&gctx->mutex);
perf_remove_from_context(group_leader);
+
+ /*
+ * Removing from the context ends up with disabled
+ * event. What we want here is event in the initial
+ * startup state, ready to be add into new context.
+ */
+ perf_event__state_init(group_leader);
list_for_each_entry(sibling, &group_leader->sibling_list,
group_entry) {
perf_remove_from_context(sibling);
+ perf_event__state_init(sibling);
put_ctx(gctx);
}
mutex_unlock(&gctx->mutex);
diff --git a/kernel/events/hw_breakpoint.c b/kernel/events/hw_breakpoint.c
index fe8a916507e..a64f8aeb5c1 100644
--- a/kernel/events/hw_breakpoint.c
+++ b/kernel/events/hw_breakpoint.c
@@ -676,7 +676,7 @@ int __init init_hw_breakpoint(void)
err_alloc:
for_each_possible_cpu(err_cpu) {
for (i = 0; i < TYPE_MAX; i++)
- kfree(per_cpu(nr_task_bp_pinned[i], cpu));
+ kfree(per_cpu(nr_task_bp_pinned[i], err_cpu));
if (err_cpu == cpu)
break;
}
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index dea7acfbb07..a567c8c7ef3 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -27,6 +27,7 @@
#include <linux/pagemap.h> /* read_mapping_page */
#include <linux/slab.h>
#include <linux/sched.h>
+#include <linux/export.h>
#include <linux/rmap.h> /* anon_vma_prepare */
#include <linux/mmu_notifier.h> /* set_pte_at_notify */
#include <linux/swap.h> /* try_to_free_swap */
@@ -41,58 +42,31 @@
#define MAX_UPROBE_XOL_SLOTS UINSNS_PER_PAGE
static struct rb_root uprobes_tree = RB_ROOT;
-
-static DEFINE_SPINLOCK(uprobes_treelock); /* serialize rbtree access */
-
-#define UPROBES_HASH_SZ 13
-
/*
- * We need separate register/unregister and mmap/munmap lock hashes because
- * of mmap_sem nesting.
- *
- * uprobe_register() needs to install probes on (potentially) all processes
- * and thus needs to acquire multiple mmap_sems (consequtively, not
- * concurrently), whereas uprobe_mmap() is called while holding mmap_sem
- * for the particular process doing the mmap.
- *
- * uprobe_register()->register_for_each_vma() needs to drop/acquire mmap_sem
- * because of lock order against i_mmap_mutex. This means there's a hole in
- * the register vma iteration where a mmap() can happen.
- *
- * Thus uprobe_register() can race with uprobe_mmap() and we can try and
- * install a probe where one is already installed.
+ * allows us to skip the uprobe_mmap if there are no uprobe events active
+ * at this time. Probably a fine grained per inode count is better?
*/
+#define no_uprobe_events() RB_EMPTY_ROOT(&uprobes_tree)
-/* serialize (un)register */
-static struct mutex uprobes_mutex[UPROBES_HASH_SZ];
-
-#define uprobes_hash(v) (&uprobes_mutex[((unsigned long)(v)) % UPROBES_HASH_SZ])
+static DEFINE_SPINLOCK(uprobes_treelock); /* serialize rbtree access */
+#define UPROBES_HASH_SZ 13
/* serialize uprobe->pending_list */
static struct mutex uprobes_mmap_mutex[UPROBES_HASH_SZ];
#define uprobes_mmap_hash(v) (&uprobes_mmap_mutex[((unsigned long)(v)) % UPROBES_HASH_SZ])
static struct percpu_rw_semaphore dup_mmap_sem;
-/*
- * uprobe_events allows us to skip the uprobe_mmap if there are no uprobe
- * events active at this time. Probably a fine grained per inode count is
- * better?
- */
-static atomic_t uprobe_events = ATOMIC_INIT(0);
-
/* Have a copy of original instruction */
#define UPROBE_COPY_INSN 0
-/* Dont run handlers when first register/ last unregister in progress*/
-#define UPROBE_RUN_HANDLER 1
/* Can skip singlestep */
-#define UPROBE_SKIP_SSTEP 2
+#define UPROBE_SKIP_SSTEP 1
struct uprobe {
struct rb_node rb_node; /* node in the rb tree */
atomic_t ref;
+ struct rw_semaphore register_rwsem;
struct rw_semaphore consumer_rwsem;
- struct mutex copy_mutex; /* TODO: kill me and UPROBE_COPY_INSN */
struct list_head pending_list;
struct uprobe_consumer *consumers;
struct inode *inode; /* Also hold a ref to inode */
@@ -430,9 +404,6 @@ static struct uprobe *insert_uprobe(struct uprobe *uprobe)
u = __insert_uprobe(uprobe);
spin_unlock(&uprobes_treelock);
- /* For now assume that the instruction need not be single-stepped */
- __set_bit(UPROBE_SKIP_SSTEP, &uprobe->flags);
-
return u;
}
@@ -452,8 +423,10 @@ static struct uprobe *alloc_uprobe(struct inode *inode, loff_t offset)
uprobe->inode = igrab(inode);
uprobe->offset = offset;
+ init_rwsem(&uprobe->register_rwsem);
init_rwsem(&uprobe->consumer_rwsem);
- mutex_init(&uprobe->copy_mutex);
+ /* For now assume that the instruction need not be single-stepped */
+ __set_bit(UPROBE_SKIP_SSTEP, &uprobe->flags);
/* add to uprobes_tree, sorted on inode:offset */
cur_uprobe = insert_uprobe(uprobe);
@@ -463,38 +436,17 @@ static struct uprobe *alloc_uprobe(struct inode *inode, loff_t offset)
kfree(uprobe);
uprobe = cur_uprobe;
iput(inode);
- } else {
- atomic_inc(&uprobe_events);
}
return uprobe;
}
-static void handler_chain(struct uprobe *uprobe, struct pt_regs *regs)
-{
- struct uprobe_consumer *uc;
-
- if (!test_bit(UPROBE_RUN_HANDLER, &uprobe->flags))
- return;
-
- down_read(&uprobe->consumer_rwsem);
- for (uc = uprobe->consumers; uc; uc = uc->next) {
- if (!uc->filter || uc->filter(uc, current))
- uc->handler(uc, regs);
- }
- up_read(&uprobe->consumer_rwsem);
-}
-
-/* Returns the previous consumer */
-static struct uprobe_consumer *
-consumer_add(struct uprobe *uprobe, struct uprobe_consumer *uc)
+static void consumer_add(struct uprobe *uprobe, struct uprobe_consumer *uc)
{
down_write(&uprobe->consumer_rwsem);
uc->next = uprobe->consumers;
uprobe->consumers = uc;
up_write(&uprobe->consumer_rwsem);
-
- return uc->next;
}
/*
@@ -588,7 +540,8 @@ static int prepare_uprobe(struct uprobe *uprobe, struct file *file,
if (test_bit(UPROBE_COPY_INSN, &uprobe->flags))
return ret;
- mutex_lock(&uprobe->copy_mutex);
+ /* TODO: move this into _register, until then we abuse this sem. */
+ down_write(&uprobe->consumer_rwsem);
if (test_bit(UPROBE_COPY_INSN, &uprobe->flags))
goto out;
@@ -612,7 +565,30 @@ static int prepare_uprobe(struct uprobe *uprobe, struct file *file,
set_bit(UPROBE_COPY_INSN, &uprobe->flags);
out:
- mutex_unlock(&uprobe->copy_mutex);
+ up_write(&uprobe->consumer_rwsem);
+
+ return ret;
+}
+
+static inline bool consumer_filter(struct uprobe_consumer *uc,
+ enum uprobe_filter_ctx ctx, struct mm_struct *mm)
+{
+ return !uc->filter || uc->filter(uc, ctx, mm);
+}
+
+static bool filter_chain(struct uprobe *uprobe,
+ enum uprobe_filter_ctx ctx, struct mm_struct *mm)
+{
+ struct uprobe_consumer *uc;
+ bool ret = false;
+
+ down_read(&uprobe->consumer_rwsem);
+ for (uc = uprobe->consumers; uc; uc = uc->next) {
+ ret = consumer_filter(uc, ctx, mm);
+ if (ret)
+ break;
+ }
+ up_read(&uprobe->consumer_rwsem);
return ret;
}
@@ -624,16 +600,6 @@ install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm,
bool first_uprobe;
int ret;
- /*
- * If probe is being deleted, unregister thread could be done with
- * the vma-rmap-walk through. Adding a probe now can be fatal since
- * nobody will be able to cleanup. Also we could be from fork or
- * mremap path, where the probe might have already been inserted.
- * Hence behave as if probe already existed.
- */
- if (!uprobe->consumers)
- return 0;
-
ret = prepare_uprobe(uprobe, vma->vm_file, mm, vaddr);
if (ret)
return ret;
@@ -658,14 +624,14 @@ install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm,
static int
remove_breakpoint(struct uprobe *uprobe, struct mm_struct *mm, unsigned long vaddr)
{
- /* can happen if uprobe_register() fails */
- if (!test_bit(MMF_HAS_UPROBES, &mm->flags))
- return 0;
-
set_bit(MMF_RECALC_UPROBES, &mm->flags);
return set_orig_insn(&uprobe->arch, mm, vaddr);
}
+static inline bool uprobe_is_active(struct uprobe *uprobe)
+{
+ return !RB_EMPTY_NODE(&uprobe->rb_node);
+}
/*
* There could be threads that have already hit the breakpoint. They
* will recheck the current insn and restart if find_uprobe() fails.
@@ -673,12 +639,15 @@ remove_breakpoint(struct uprobe *uprobe, struct mm_struct *mm, unsigned long vad
*/
static void delete_uprobe(struct uprobe *uprobe)
{
+ if (WARN_ON(!uprobe_is_active(uprobe)))
+ return;
+
spin_lock(&uprobes_treelock);
rb_erase(&uprobe->rb_node, &uprobes_tree);
spin_unlock(&uprobes_treelock);
+ RB_CLEAR_NODE(&uprobe->rb_node); /* for uprobe_is_active() */
iput(uprobe->inode);
put_uprobe(uprobe);
- atomic_dec(&uprobe_events);
}
struct map_info {
@@ -764,8 +733,10 @@ build_map_info(struct address_space *mapping, loff_t offset, bool is_register)
return curr;
}
-static int register_for_each_vma(struct uprobe *uprobe, bool is_register)
+static int
+register_for_each_vma(struct uprobe *uprobe, struct uprobe_consumer *new)
{
+ bool is_register = !!new;
struct map_info *info;
int err = 0;
@@ -794,10 +765,16 @@ static int register_for_each_vma(struct uprobe *uprobe, bool is_register)
vaddr_to_offset(vma, info->vaddr) != uprobe->offset)
goto unlock;
- if (is_register)
- err = install_breakpoint(uprobe, mm, vma, info->vaddr);
- else
- err |= remove_breakpoint(uprobe, mm, info->vaddr);
+ if (is_register) {
+ /* consult only the "caller", new consumer. */
+ if (consumer_filter(new,
+ UPROBE_FILTER_REGISTER, mm))
+ err = install_breakpoint(uprobe, mm, vma, info->vaddr);
+ } else if (test_bit(MMF_HAS_UPROBES, &mm->flags)) {
+ if (!filter_chain(uprobe,
+ UPROBE_FILTER_UNREGISTER, mm))
+ err |= remove_breakpoint(uprobe, mm, info->vaddr);
+ }
unlock:
up_write(&mm->mmap_sem);
@@ -810,17 +787,23 @@ static int register_for_each_vma(struct uprobe *uprobe, bool is_register)
return err;
}
-static int __uprobe_register(struct uprobe *uprobe)
+static int __uprobe_register(struct uprobe *uprobe, struct uprobe_consumer *uc)
{
- return register_for_each_vma(uprobe, true);
+ consumer_add(uprobe, uc);
+ return register_for_each_vma(uprobe, uc);
}
-static void __uprobe_unregister(struct uprobe *uprobe)
+static void __uprobe_unregister(struct uprobe *uprobe, struct uprobe_consumer *uc)
{
- if (!register_for_each_vma(uprobe, false))
- delete_uprobe(uprobe);
+ int err;
+
+ if (!consumer_del(uprobe, uc)) /* WARN? */
+ return;
+ err = register_for_each_vma(uprobe, NULL);
/* TODO : cant unregister? schedule a worker thread */
+ if (!uprobe->consumers && !err)
+ delete_uprobe(uprobe);
}
/*
@@ -845,31 +828,59 @@ int uprobe_register(struct inode *inode, loff_t offset, struct uprobe_consumer *
struct uprobe *uprobe;
int ret;
- if (!inode || !uc || uc->next)
- return -EINVAL;
-
+ /* Racy, just to catch the obvious mistakes */
if (offset > i_size_read(inode))
return -EINVAL;
- ret = 0;
- mutex_lock(uprobes_hash(inode));
+ retry:
uprobe = alloc_uprobe(inode, offset);
-
- if (!uprobe) {
- ret = -ENOMEM;
- } else if (!consumer_add(uprobe, uc)) {
- ret = __uprobe_register(uprobe);
- if (ret) {
- uprobe->consumers = NULL;
- __uprobe_unregister(uprobe);
- } else {
- set_bit(UPROBE_RUN_HANDLER, &uprobe->flags);
- }
+ if (!uprobe)
+ return -ENOMEM;
+ /*
+ * We can race with uprobe_unregister()->delete_uprobe().
+ * Check uprobe_is_active() and retry if it is false.
+ */
+ down_write(&uprobe->register_rwsem);
+ ret = -EAGAIN;
+ if (likely(uprobe_is_active(uprobe))) {
+ ret = __uprobe_register(uprobe, uc);
+ if (ret)
+ __uprobe_unregister(uprobe, uc);
}
+ up_write(&uprobe->register_rwsem);
+ put_uprobe(uprobe);
- mutex_unlock(uprobes_hash(inode));
- if (uprobe)
- put_uprobe(uprobe);
+ if (unlikely(ret == -EAGAIN))
+ goto retry;
+ return ret;
+}
+EXPORT_SYMBOL_GPL(uprobe_register);
+
+/*
+ * uprobe_apply - unregister a already registered probe.
+ * @inode: the file in which the probe has to be removed.
+ * @offset: offset from the start of the file.
+ * @uc: consumer which wants to add more or remove some breakpoints
+ * @add: add or remove the breakpoints
+ */
+int uprobe_apply(struct inode *inode, loff_t offset,
+ struct uprobe_consumer *uc, bool add)
+{
+ struct uprobe *uprobe;
+ struct uprobe_consumer *con;
+ int ret = -ENOENT;
+
+ uprobe = find_uprobe(inode, offset);
+ if (!uprobe)
+ return ret;
+
+ down_write(&uprobe->register_rwsem);
+ for (con = uprobe->consumers; con && con != uc ; con = con->next)
+ ;
+ if (con)
+ ret = register_for_each_vma(uprobe, add ? uc : NULL);
+ up_write(&uprobe->register_rwsem);
+ put_uprobe(uprobe);
return ret;
}
@@ -884,25 +895,42 @@ void uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consume
{
struct uprobe *uprobe;
- if (!inode || !uc)
- return;
-
uprobe = find_uprobe(inode, offset);
if (!uprobe)
return;
- mutex_lock(uprobes_hash(inode));
+ down_write(&uprobe->register_rwsem);
+ __uprobe_unregister(uprobe, uc);
+ up_write(&uprobe->register_rwsem);
+ put_uprobe(uprobe);
+}
+EXPORT_SYMBOL_GPL(uprobe_unregister);
- if (consumer_del(uprobe, uc)) {
- if (!uprobe->consumers) {
- __uprobe_unregister(uprobe);
- clear_bit(UPROBE_RUN_HANDLER, &uprobe->flags);
- }
+static int unapply_uprobe(struct uprobe *uprobe, struct mm_struct *mm)
+{
+ struct vm_area_struct *vma;
+ int err = 0;
+
+ down_read(&mm->mmap_sem);
+ for (vma = mm->mmap; vma; vma = vma->vm_next) {
+ unsigned long vaddr;
+ loff_t offset;
+
+ if (!valid_vma(vma, false) ||
+ vma->vm_file->f_mapping->host != uprobe->inode)
+ continue;
+
+ offset = (loff_t)vma->vm_pgoff << PAGE_SHIFT;
+ if (uprobe->offset < offset ||
+ uprobe->offset >= offset + vma->vm_end - vma->vm_start)
+ continue;
+
+ vaddr = offset_to_vaddr(vma, uprobe->offset);
+ err |= remove_breakpoint(uprobe, mm, vaddr);
}
+ up_read(&mm->mmap_sem);
- mutex_unlock(uprobes_hash(inode));
- if (uprobe)
- put_uprobe(uprobe);
+ return err;
}
static struct rb_node *
@@ -979,7 +1007,7 @@ int uprobe_mmap(struct vm_area_struct *vma)
struct uprobe *uprobe, *u;
struct inode *inode;
- if (!atomic_read(&uprobe_events) || !valid_vma(vma, true))
+ if (no_uprobe_events() || !valid_vma(vma, true))
return 0;
inode = vma->vm_file->f_mapping->host;
@@ -988,9 +1016,14 @@ int uprobe_mmap(struct vm_area_struct *vma)
mutex_lock(uprobes_mmap_hash(inode));
build_probe_list(inode, vma, vma->vm_start, vma->vm_end, &tmp_list);
-
+ /*
+ * We can race with uprobe_unregister(), this uprobe can be already
+ * removed. But in this case filter_chain() must return false, all
+ * consumers have gone away.
+ */
list_for_each_entry_safe(uprobe, u, &tmp_list, pending_list) {
- if (!fatal_signal_pending(current)) {
+ if (!fatal_signal_pending(current) &&
+ filter_chain(uprobe, UPROBE_FILTER_MMAP, vma->vm_mm)) {
unsigned long vaddr = offset_to_vaddr(vma, uprobe->offset);
install_breakpoint(uprobe, vma->vm_mm, vma, vaddr);
}
@@ -1025,7 +1058,7 @@ vma_has_uprobes(struct vm_area_struct *vma, unsigned long start, unsigned long e
*/
void uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned long end)
{
- if (!atomic_read(&uprobe_events) || !valid_vma(vma, false))
+ if (no_uprobe_events() || !valid_vma(vma, false))
return;
if (!atomic_read(&vma->vm_mm->mm_users)) /* called by mmput() ? */
@@ -1042,22 +1075,14 @@ void uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned lon
/* Slot allocation for XOL */
static int xol_add_vma(struct xol_area *area)
{
- struct mm_struct *mm;
- int ret;
-
- area->page = alloc_page(GFP_HIGHUSER);
- if (!area->page)
- return -ENOMEM;
-
- ret = -EALREADY;
- mm = current->mm;
+ struct mm_struct *mm = current->mm;
+ int ret = -EALREADY;
down_write(&mm->mmap_sem);
if (mm->uprobes_state.xol_area)
goto fail;
ret = -ENOMEM;
-
/* Try to map as high as possible, this is only a hint. */
area->vaddr = get_unmapped_area(NULL, TASK_SIZE - PAGE_SIZE, PAGE_SIZE, 0, 0);
if (area->vaddr & ~PAGE_MASK) {
@@ -1073,54 +1098,53 @@ static int xol_add_vma(struct xol_area *area)
smp_wmb(); /* pairs with get_xol_area() */
mm->uprobes_state.xol_area = area;
ret = 0;
-
-fail:
+ fail:
up_write(&mm->mmap_sem);
- if (ret)
- __free_page(area->page);
return ret;
}
-static struct xol_area *get_xol_area(struct mm_struct *mm)
-{
- struct xol_area *area;
-
- area = mm->uprobes_state.xol_area;
- smp_read_barrier_depends(); /* pairs with wmb in xol_add_vma() */
-
- return area;
-}
-
/*
- * xol_alloc_area - Allocate process's xol_area.
- * This area will be used for storing instructions for execution out of
- * line.
+ * get_xol_area - Allocate process's xol_area if necessary.
+ * This area will be used for storing instructions for execution out of line.
*
* Returns the allocated area or NULL.
*/
-static struct xol_area *xol_alloc_area(void)
+static struct xol_area *get_xol_area(void)
{
+ struct mm_struct *mm = current->mm;
struct xol_area *area;
+ area = mm->uprobes_state.xol_area;
+ if (area)
+ goto ret;
+
area = kzalloc(sizeof(*area), GFP_KERNEL);
if (unlikely(!area))
- return NULL;
+ goto out;
area->bitmap = kzalloc(BITS_TO_LONGS(UINSNS_PER_PAGE) * sizeof(long), GFP_KERNEL);
-
if (!area->bitmap)
- goto fail;
+ goto free_area;
+
+ area->page = alloc_page(GFP_HIGHUSER);
+ if (!area->page)
+ goto free_bitmap;
init_waitqueue_head(&area->wq);
if (!xol_add_vma(area))
return area;
-fail:
+ __free_page(area->page);
+ free_bitmap:
kfree(area->bitmap);
+ free_area:
kfree(area);
-
- return get_xol_area(current->mm);
+ out:
+ area = mm->uprobes_state.xol_area;
+ ret:
+ smp_read_barrier_depends(); /* pairs with wmb in xol_add_vma() */
+ return area;
}
/*
@@ -1186,33 +1210,26 @@ static unsigned long xol_take_insn_slot(struct xol_area *area)
}
/*
- * xol_get_insn_slot - If was not allocated a slot, then
- * allocate a slot.
+ * xol_get_insn_slot - allocate a slot for xol.
* Returns the allocated slot address or 0.
*/
-static unsigned long xol_get_insn_slot(struct uprobe *uprobe, unsigned long slot_addr)
+static unsigned long xol_get_insn_slot(struct uprobe *uprobe)
{
struct xol_area *area;
unsigned long offset;
+ unsigned long xol_vaddr;
void *vaddr;
- area = get_xol_area(current->mm);
- if (!area) {
- area = xol_alloc_area();
- if (!area)
- return 0;
- }
- current->utask->xol_vaddr = xol_take_insn_slot(area);
+ area = get_xol_area();
+ if (!area)
+ return 0;
- /*
- * Initialize the slot if xol_vaddr points to valid
- * instruction slot.
- */
- if (unlikely(!current->utask->xol_vaddr))
+ xol_vaddr = xol_take_insn_slot(area);
+ if (unlikely(!xol_vaddr))
return 0;
- current->utask->vaddr = slot_addr;
- offset = current->utask->xol_vaddr & ~PAGE_MASK;
+ /* Initialize the slot */
+ offset = xol_vaddr & ~PAGE_MASK;
vaddr = kmap_atomic(area->page);
memcpy(vaddr + offset, uprobe->arch.insn, MAX_UINSN_BYTES);
kunmap_atomic(vaddr);
@@ -1222,7 +1239,7 @@ static unsigned long xol_get_insn_slot(struct uprobe *uprobe, unsigned long slot
*/
flush_dcache_page(area->page);
- return current->utask->xol_vaddr;
+ return xol_vaddr;
}
/*
@@ -1240,8 +1257,7 @@ static void xol_free_insn_slot(struct task_struct *tsk)
return;
slot_addr = tsk->utask->xol_vaddr;
-
- if (unlikely(!slot_addr || IS_ERR_VALUE(slot_addr)))
+ if (unlikely(!slot_addr))
return;
area = tsk->mm->uprobes_state.xol_area;
@@ -1303,33 +1319,48 @@ void uprobe_copy_process(struct task_struct *t)
}
/*
- * Allocate a uprobe_task object for the task.
- * Called when the thread hits a breakpoint for the first time.
+ * Allocate a uprobe_task object for the task if if necessary.
+ * Called when the thread hits a breakpoint.
*
* Returns:
* - pointer to new uprobe_task on success
* - NULL otherwise
*/
-static struct uprobe_task *add_utask(void)
+static struct uprobe_task *get_utask(void)
{
- struct uprobe_task *utask;
-
- utask = kzalloc(sizeof *utask, GFP_KERNEL);
- if (unlikely(!utask))
- return NULL;
-
- current->utask = utask;
- return utask;
+ if (!current->utask)
+ current->utask = kzalloc(sizeof(struct uprobe_task), GFP_KERNEL);
+ return current->utask;
}
/* Prepare to single-step probed instruction out of line. */
static int
-pre_ssout(struct uprobe *uprobe, struct pt_regs *regs, unsigned long vaddr)
+pre_ssout(struct uprobe *uprobe, struct pt_regs *regs, unsigned long bp_vaddr)
{
- if (xol_get_insn_slot(uprobe, vaddr) && !arch_uprobe_pre_xol(&uprobe->arch, regs))
- return 0;
+ struct uprobe_task *utask;
+ unsigned long xol_vaddr;
+ int err;
+
+ utask = get_utask();
+ if (!utask)
+ return -ENOMEM;
+
+ xol_vaddr = xol_get_insn_slot(uprobe);
+ if (!xol_vaddr)
+ return -ENOMEM;
+
+ utask->xol_vaddr = xol_vaddr;
+ utask->vaddr = bp_vaddr;
+
+ err = arch_uprobe_pre_xol(&uprobe->arch, regs);
+ if (unlikely(err)) {
+ xol_free_insn_slot(current);
+ return err;
+ }
- return -EFAULT;
+ utask->active_uprobe = uprobe;
+ utask->state = UTASK_SSTEP;
+ return 0;
}
/*
@@ -1391,6 +1422,7 @@ static void mmf_recalc_uprobes(struct mm_struct *mm)
* This is not strictly accurate, we can race with
* uprobe_unregister() and see the already removed
* uprobe if delete_uprobe() was not yet called.
+ * Or this uprobe can be filtered out.
*/
if (vma_has_uprobes(vma, vma->vm_start, vma->vm_end))
return;
@@ -1452,13 +1484,33 @@ static struct uprobe *find_active_uprobe(unsigned long bp_vaddr, int *is_swbp)
return uprobe;
}
+static void handler_chain(struct uprobe *uprobe, struct pt_regs *regs)
+{
+ struct uprobe_consumer *uc;
+ int remove = UPROBE_HANDLER_REMOVE;
+
+ down_read(&uprobe->register_rwsem);
+ for (uc = uprobe->consumers; uc; uc = uc->next) {
+ int rc = uc->handler(uc, regs);
+
+ WARN(rc & ~UPROBE_HANDLER_MASK,
+ "bad rc=0x%x from %pf()\n", rc, uc->handler);
+ remove &= rc;
+ }
+
+ if (remove && uprobe->consumers) {
+ WARN_ON(!uprobe_is_active(uprobe));
+ unapply_uprobe(uprobe, current->mm);
+ }
+ up_read(&uprobe->register_rwsem);
+}
+
/*
* Run handler and ask thread to singlestep.
* Ensure all non-fatal signals cannot interrupt thread while it singlesteps.
*/
static void handle_swbp(struct pt_regs *regs)
{
- struct uprobe_task *utask;
struct uprobe *uprobe;
unsigned long bp_vaddr;
int uninitialized_var(is_swbp);
@@ -1483,6 +1535,10 @@ static void handle_swbp(struct pt_regs *regs)
}
return;
}
+
+ /* change it in advance for ->handler() and restart */
+ instruction_pointer_set(regs, bp_vaddr);
+
/*
* TODO: move copy_insn/etc into _register and remove this hack.
* After we hit the bp, _unregister + _register can install the
@@ -1490,32 +1546,16 @@ static void handle_swbp(struct pt_regs *regs)
*/
smp_rmb(); /* pairs with wmb() in install_breakpoint() */
if (unlikely(!test_bit(UPROBE_COPY_INSN, &uprobe->flags)))
- goto restart;
-
- utask = current->utask;
- if (!utask) {
- utask = add_utask();
- /* Cannot allocate; re-execute the instruction. */
- if (!utask)
- goto restart;
- }
+ goto out;
handler_chain(uprobe, regs);
if (can_skip_sstep(uprobe, regs))
goto out;
- if (!pre_ssout(uprobe, regs, bp_vaddr)) {
- utask->active_uprobe = uprobe;
- utask->state = UTASK_SSTEP;
+ if (!pre_ssout(uprobe, regs, bp_vaddr))
return;
- }
-restart:
- /*
- * cannot singlestep; cannot skip instruction;
- * re-execute the instruction.
- */
- instruction_pointer_set(regs, bp_vaddr);
+ /* can_skip_sstep() succeeded, or restart if can't singlestep */
out:
put_uprobe(uprobe);
}
@@ -1609,10 +1649,8 @@ static int __init init_uprobes(void)
{
int i;
- for (i = 0; i < UPROBES_HASH_SZ; i++) {
- mutex_init(&uprobes_mutex[i]);
+ for (i = 0; i < UPROBES_HASH_SZ; i++)
mutex_init(&uprobes_mmap_mutex[i]);
- }
if (percpu_init_rwsem(&dup_mmap_sem))
return -ENOMEM;
diff --git a/kernel/exit.c b/kernel/exit.c
index b4df2193721..7dd20408707 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -85,6 +85,7 @@ static void __exit_signal(struct task_struct *tsk)
bool group_dead = thread_group_leader(tsk);
struct sighand_struct *sighand;
struct tty_struct *uninitialized_var(tty);
+ cputime_t utime, stime;
sighand = rcu_dereference_check(tsk->sighand,
lockdep_tasklist_lock_is_held());
@@ -123,9 +124,10 @@ static void __exit_signal(struct task_struct *tsk)
* We won't ever get here for the group leader, since it
* will have been the last reference on the signal_struct.
*/
- sig->utime += tsk->utime;
- sig->stime += tsk->stime;
- sig->gtime += tsk->gtime;
+ task_cputime(tsk, &utime, &stime);
+ sig->utime += utime;
+ sig->stime += stime;
+ sig->gtime += task_gtime(tsk);
sig->min_flt += tsk->min_flt;
sig->maj_flt += tsk->maj_flt;
sig->nvcsw += tsk->nvcsw;
@@ -1092,7 +1094,7 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
sig = p->signal;
psig->cutime += tgutime + sig->cutime;
psig->cstime += tgstime + sig->cstime;
- psig->cgtime += p->gtime + sig->gtime + sig->cgtime;
+ psig->cgtime += task_gtime(p) + sig->gtime + sig->cgtime;
psig->cmin_flt +=
p->min_flt + sig->min_flt + sig->cmin_flt;
psig->cmaj_flt +=
diff --git a/kernel/fork.c b/kernel/fork.c
index 65ca6d27f24..4133876d8cd 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1233,6 +1233,12 @@ static struct task_struct *copy_process(unsigned long clone_flags,
#ifndef CONFIG_VIRT_CPU_ACCOUNTING
p->prev_cputime.utime = p->prev_cputime.stime = 0;
#endif
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
+ seqlock_init(&p->vtime_seqlock);
+ p->vtime_snap = 0;
+ p->vtime_snap_whence = VTIME_SLEEPING;
+#endif
+
#if defined(SPLIT_RSS_COUNTING)
memset(&p->rss_stat, 0, sizeof(p->rss_stat));
#endif
@@ -1668,8 +1674,10 @@ SYSCALL_DEFINE5(clone, unsigned long, clone_flags, unsigned long, newsp,
int, tls_val)
#endif
{
- return do_fork(clone_flags, newsp, 0,
- parent_tidptr, child_tidptr);
+ long ret = do_fork(clone_flags, newsp, 0, parent_tidptr, child_tidptr);
+ asmlinkage_protect(5, ret, clone_flags, newsp,
+ parent_tidptr, child_tidptr, tls_val);
+ return ret;
}
#endif
diff --git a/kernel/futex.c b/kernel/futex.c
index 19eb089ca00..9618b6e9fb3 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -60,6 +60,7 @@
#include <linux/pid.h>
#include <linux/nsproxy.h>
#include <linux/ptrace.h>
+#include <linux/sched/rt.h>
#include <asm/futex.h>
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 6db7a5ed52b..cc47812d3fe 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -44,6 +44,8 @@
#include <linux/err.h>
#include <linux/debugobjects.h>
#include <linux/sched.h>
+#include <linux/sched/sysctl.h>
+#include <linux/sched/rt.h>
#include <linux/timer.h>
#include <asm/uaccess.h>
@@ -640,21 +642,9 @@ static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base)
* and expiry check is done in the hrtimer_interrupt or in the softirq.
*/
static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
- struct hrtimer_clock_base *base,
- int wakeup)
+ struct hrtimer_clock_base *base)
{
- if (base->cpu_base->hres_active && hrtimer_reprogram(timer, base)) {
- if (wakeup) {
- raw_spin_unlock(&base->cpu_base->lock);
- raise_softirq_irqoff(HRTIMER_SOFTIRQ);
- raw_spin_lock(&base->cpu_base->lock);
- } else
- __raise_softirq_irqoff(HRTIMER_SOFTIRQ);
-
- return 1;
- }
-
- return 0;
+ return base->cpu_base->hres_active && hrtimer_reprogram(timer, base);
}
static inline ktime_t hrtimer_update_base(struct hrtimer_cpu_base *base)
@@ -735,8 +725,7 @@ static inline int hrtimer_switch_to_hres(void) { return 0; }
static inline void
hrtimer_force_reprogram(struct hrtimer_cpu_base *base, int skip_equal) { }
static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer,
- struct hrtimer_clock_base *base,
- int wakeup)
+ struct hrtimer_clock_base *base)
{
return 0;
}
@@ -995,8 +984,21 @@ int __hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
*
* XXX send_remote_softirq() ?
*/
- if (leftmost && new_base->cpu_base == &__get_cpu_var(hrtimer_bases))
- hrtimer_enqueue_reprogram(timer, new_base, wakeup);
+ if (leftmost && new_base->cpu_base == &__get_cpu_var(hrtimer_bases)
+ && hrtimer_enqueue_reprogram(timer, new_base)) {
+ if (wakeup) {
+ /*
+ * We need to drop cpu_base->lock to avoid a
+ * lock ordering issue vs. rq->lock.
+ */
+ raw_spin_unlock(&new_base->cpu_base->lock);
+ raise_softirq_irqoff(HRTIMER_SOFTIRQ);
+ local_irq_restore(flags);
+ return ret;
+ } else {
+ __raise_softirq_irqoff(HRTIMER_SOFTIRQ);
+ }
+ }
unlock_hrtimer_base(timer, &flags);
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 3aca9f29d30..cbd97ce0b00 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -90,27 +90,41 @@ int irq_set_handler_data(unsigned int irq, void *data)
EXPORT_SYMBOL(irq_set_handler_data);
/**
- * irq_set_msi_desc - set MSI descriptor data for an irq
- * @irq: Interrupt number
- * @entry: Pointer to MSI descriptor data
+ * irq_set_msi_desc_off - set MSI descriptor data for an irq at offset
+ * @irq_base: Interrupt number base
+ * @irq_offset: Interrupt number offset
+ * @entry: Pointer to MSI descriptor data
*
- * Set the MSI descriptor entry for an irq
+ * Set the MSI descriptor entry for an irq at offset
*/
-int irq_set_msi_desc(unsigned int irq, struct msi_desc *entry)
+int irq_set_msi_desc_off(unsigned int irq_base, unsigned int irq_offset,
+ struct msi_desc *entry)
{
unsigned long flags;
- struct irq_desc *desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
+ struct irq_desc *desc = irq_get_desc_lock(irq_base + irq_offset, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
if (!desc)
return -EINVAL;
desc->irq_data.msi_desc = entry;
- if (entry)
- entry->irq = irq;
+ if (entry && !irq_offset)
+ entry->irq = irq_base;
irq_put_desc_unlock(desc, flags);
return 0;
}
/**
+ * irq_set_msi_desc - set MSI descriptor data for an irq
+ * @irq: Interrupt number
+ * @entry: Pointer to MSI descriptor data
+ *
+ * Set the MSI descriptor entry for an irq
+ */
+int irq_set_msi_desc(unsigned int irq, struct msi_desc *entry)
+{
+ return irq_set_msi_desc_off(irq, 0, entry);
+}
+
+/**
* irq_set_chip_data - set irq chip data for an irq
* @irq: Interrupt number
* @data: Pointer to chip specific data
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index e49a288fa47..fa17855ca65 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -16,6 +16,7 @@
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/sched.h>
+#include <linux/sched/rt.h>
#include <linux/task_work.h>
#include "internals.h"
@@ -1524,6 +1525,7 @@ void enable_percpu_irq(unsigned int irq, unsigned int type)
out:
irq_put_desc_unlock(desc, flags);
}
+EXPORT_SYMBOL_GPL(enable_percpu_irq);
void disable_percpu_irq(unsigned int irq)
{
@@ -1537,6 +1539,7 @@ void disable_percpu_irq(unsigned int irq)
irq_percpu_disable(desc, cpu);
irq_put_desc_unlock(desc, flags);
}
+EXPORT_SYMBOL_GPL(disable_percpu_irq);
/*
* Internal function to unregister a percpu irqaction.
diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
index 611cd6003c4..7b5f012bde9 100644
--- a/kernel/irq/spurious.c
+++ b/kernel/irq/spurious.c
@@ -80,13 +80,11 @@ static int try_one_irq(int irq, struct irq_desc *desc, bool force)
/*
* All handlers must agree on IRQF_SHARED, so we test just the
- * first. Check for action->next as well.
+ * first.
*/
action = desc->action;
if (!action || !(action->flags & IRQF_SHARED) ||
- (action->flags & __IRQF_TIMER) ||
- (action->handler(irq, action->dev_id) == IRQ_HANDLED) ||
- !action->next)
+ (action->flags & __IRQF_TIMER))
goto out;
/* Already running on another processor */
@@ -104,6 +102,7 @@ static int try_one_irq(int irq, struct irq_desc *desc, bool force)
do {
if (handle_irq_event(desc) == IRQ_HANDLED)
ret = IRQ_HANDLED;
+ /* Make sure that there is still a valid action */
action = desc->action;
} while ((desc->istate & IRQS_PENDING) && action);
desc->istate &= ~IRQS_POLL_INPROGRESS;
diff --git a/kernel/irq_work.c b/kernel/irq_work.c
index 1588e3b2871..55fcce6065c 100644
--- a/kernel/irq_work.c
+++ b/kernel/irq_work.c
@@ -12,37 +12,36 @@
#include <linux/percpu.h>
#include <linux/hardirq.h>
#include <linux/irqflags.h>
+#include <linux/sched.h>
+#include <linux/tick.h>
+#include <linux/cpu.h>
+#include <linux/notifier.h>
#include <asm/processor.h>
-/*
- * An entry can be in one of four states:
- *
- * free NULL, 0 -> {claimed} : free to be used
- * claimed NULL, 3 -> {pending} : claimed to be enqueued
- * pending next, 3 -> {busy} : queued, pending callback
- * busy NULL, 2 -> {free, claimed} : callback in progress, can be claimed
- */
-
-#define IRQ_WORK_PENDING 1UL
-#define IRQ_WORK_BUSY 2UL
-#define IRQ_WORK_FLAGS 3UL
static DEFINE_PER_CPU(struct llist_head, irq_work_list);
+static DEFINE_PER_CPU(int, irq_work_raised);
/*
* Claim the entry so that no one else will poke at it.
*/
static bool irq_work_claim(struct irq_work *work)
{
- unsigned long flags, nflags;
+ unsigned long flags, oflags, nflags;
+ /*
+ * Start with our best wish as a premise but only trust any
+ * flag value after cmpxchg() result.
+ */
+ flags = work->flags & ~IRQ_WORK_PENDING;
for (;;) {
- flags = work->flags;
- if (flags & IRQ_WORK_PENDING)
- return false;
nflags = flags | IRQ_WORK_FLAGS;
- if (cmpxchg(&work->flags, flags, nflags) == flags)
+ oflags = cmpxchg(&work->flags, flags, nflags);
+ if (oflags == flags)
break;
+ if (oflags & IRQ_WORK_PENDING)
+ return false;
+ flags = oflags;
cpu_relax();
}
@@ -57,57 +56,69 @@ void __weak arch_irq_work_raise(void)
}
/*
- * Queue the entry and raise the IPI if needed.
+ * Enqueue the irq_work @entry unless it's already pending
+ * somewhere.
+ *
+ * Can be re-enqueued while the callback is still in progress.
*/
-static void __irq_work_queue(struct irq_work *work)
+void irq_work_queue(struct irq_work *work)
{
- bool empty;
+ /* Only queue if not already pending */
+ if (!irq_work_claim(work))
+ return;
+ /* Queue the entry and raise the IPI if needed. */
preempt_disable();
- empty = llist_add(&work->llnode, &__get_cpu_var(irq_work_list));
- /* The list was empty, raise self-interrupt to start processing. */
- if (empty)
- arch_irq_work_raise();
+ llist_add(&work->llnode, &__get_cpu_var(irq_work_list));
+
+ /*
+ * If the work is not "lazy" or the tick is stopped, raise the irq
+ * work interrupt (if supported by the arch), otherwise, just wait
+ * for the next tick.
+ */
+ if (!(work->flags & IRQ_WORK_LAZY) || tick_nohz_tick_stopped()) {
+ if (!this_cpu_cmpxchg(irq_work_raised, 0, 1))
+ arch_irq_work_raise();
+ }
preempt_enable();
}
+EXPORT_SYMBOL_GPL(irq_work_queue);
-/*
- * Enqueue the irq_work @entry, returns true on success, failure when the
- * @entry was already enqueued by someone else.
- *
- * Can be re-enqueued while the callback is still in progress.
- */
-bool irq_work_queue(struct irq_work *work)
+bool irq_work_needs_cpu(void)
{
- if (!irq_work_claim(work)) {
- /*
- * Already enqueued, can't do!
- */
+ struct llist_head *this_list;
+
+ this_list = &__get_cpu_var(irq_work_list);
+ if (llist_empty(this_list))
return false;
- }
- __irq_work_queue(work);
+ /* All work should have been flushed before going offline */
+ WARN_ON_ONCE(cpu_is_offline(smp_processor_id()));
+
return true;
}
-EXPORT_SYMBOL_GPL(irq_work_queue);
-/*
- * Run the irq_work entries on this cpu. Requires to be ran from hardirq
- * context with local IRQs disabled.
- */
-void irq_work_run(void)
+static void __irq_work_run(void)
{
+ unsigned long flags;
struct irq_work *work;
struct llist_head *this_list;
struct llist_node *llnode;
+
+ /*
+ * Reset the "raised" state right before we check the list because
+ * an NMI may enqueue after we find the list empty from the runner.
+ */
+ __this_cpu_write(irq_work_raised, 0);
+ barrier();
+
this_list = &__get_cpu_var(irq_work_list);
if (llist_empty(this_list))
return;
- BUG_ON(!in_irq());
BUG_ON(!irqs_disabled());
llnode = llist_del_all(this_list);
@@ -119,16 +130,31 @@ void irq_work_run(void)
/*
* Clear the PENDING bit, after this point the @work
* can be re-used.
+ * Make it immediately visible so that other CPUs trying
+ * to claim that work don't rely on us to handle their data
+ * while we are in the middle of the func.
*/
- work->flags = IRQ_WORK_BUSY;
+ flags = work->flags & ~IRQ_WORK_PENDING;
+ xchg(&work->flags, flags);
+
work->func(work);
/*
* Clear the BUSY bit and return to the free state if
* no-one else claimed it meanwhile.
*/
- (void)cmpxchg(&work->flags, IRQ_WORK_BUSY, 0);
+ (void)cmpxchg(&work->flags, flags, flags & ~IRQ_WORK_BUSY);
}
}
+
+/*
+ * Run the irq_work entries on this cpu. Requires to be ran from hardirq
+ * context with local IRQs disabled.
+ */
+void irq_work_run(void)
+{
+ BUG_ON(!in_irq());
+ __irq_work_run();
+}
EXPORT_SYMBOL_GPL(irq_work_run);
/*
@@ -143,3 +169,35 @@ void irq_work_sync(struct irq_work *work)
cpu_relax();
}
EXPORT_SYMBOL_GPL(irq_work_sync);
+
+#ifdef CONFIG_HOTPLUG_CPU
+static int irq_work_cpu_notify(struct notifier_block *self,
+ unsigned long action, void *hcpu)
+{
+ long cpu = (long)hcpu;
+
+ switch (action) {
+ case CPU_DYING:
+ /* Called from stop_machine */
+ if (WARN_ON_ONCE(cpu != smp_processor_id()))
+ break;
+ __irq_work_run();
+ break;
+ default:
+ break;
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block cpu_notify;
+
+static __init int irq_work_init_cpu_notifier(void)
+{
+ cpu_notify.notifier_call = irq_work_cpu_notify;
+ cpu_notify.priority = 0;
+ register_cpu_notifier(&cpu_notify);
+ return 0;
+}
+device_initcall(irq_work_init_cpu_notifier);
+
+#endif /* CONFIG_HOTPLUG_CPU */
diff --git a/kernel/kmod.c b/kernel/kmod.c
index 0023a87e8de..56dd34976d7 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -38,6 +38,7 @@
#include <linux/suspend.h>
#include <linux/rwsem.h>
#include <linux/ptrace.h>
+#include <linux/async.h>
#include <asm/uaccess.h>
#include <trace/events/module.h>
@@ -130,6 +131,14 @@ int __request_module(bool wait, const char *fmt, ...)
#define MAX_KMOD_CONCURRENT 50 /* Completely arbitrary value - KAO */
static int kmod_loop_msg;
+ /*
+ * We don't allow synchronous module loading from async. Module
+ * init may invoke async_synchronize_full() which will end up
+ * waiting for this task which already is waiting for the module
+ * loading to complete, leading to a deadlock.
+ */
+ WARN_ON_ONCE(wait && current_is_async());
+
va_start(args, fmt);
ret = vsnprintf(module_name, MODULE_NAME_LEN, fmt, args);
va_end(args);
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 098f396aa40..550294d58a0 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -471,7 +471,6 @@ static LIST_HEAD(unoptimizing_list);
static void kprobe_optimizer(struct work_struct *work);
static DECLARE_DELAYED_WORK(optimizing_work, kprobe_optimizer);
-static DECLARE_COMPLETION(optimizer_comp);
#define OPTIMIZE_DELAY 5
/*
@@ -552,8 +551,7 @@ static __kprobes void do_free_cleaned_kprobes(struct list_head *free_list)
/* Start optimizer after OPTIMIZE_DELAY passed */
static __kprobes void kick_kprobe_optimizer(void)
{
- if (!delayed_work_pending(&optimizing_work))
- schedule_delayed_work(&optimizing_work, OPTIMIZE_DELAY);
+ schedule_delayed_work(&optimizing_work, OPTIMIZE_DELAY);
}
/* Kprobe jump optimizer */
@@ -592,16 +590,25 @@ static __kprobes void kprobe_optimizer(struct work_struct *work)
/* Step 5: Kick optimizer again if needed */
if (!list_empty(&optimizing_list) || !list_empty(&unoptimizing_list))
kick_kprobe_optimizer();
- else
- /* Wake up all waiters */
- complete_all(&optimizer_comp);
}
/* Wait for completing optimization and unoptimization */
static __kprobes void wait_for_kprobe_optimizer(void)
{
- if (delayed_work_pending(&optimizing_work))
- wait_for_completion(&optimizer_comp);
+ mutex_lock(&kprobe_mutex);
+
+ while (!list_empty(&optimizing_list) || !list_empty(&unoptimizing_list)) {
+ mutex_unlock(&kprobe_mutex);
+
+ /* this will also make optimizing_work execute immmediately */
+ flush_delayed_work(&optimizing_work);
+ /* @optimizing_work might not have been queued yet, relax */
+ cpu_relax();
+
+ mutex_lock(&kprobe_mutex);
+ }
+
+ mutex_unlock(&kprobe_mutex);
}
/* Optimize kprobe if p is ready to be optimized */
@@ -919,7 +926,7 @@ static __kprobes struct kprobe *alloc_aggr_kprobe(struct kprobe *p)
}
#endif /* CONFIG_OPTPROBES */
-#ifdef KPROBES_CAN_USE_FTRACE
+#ifdef CONFIG_KPROBES_ON_FTRACE
static struct ftrace_ops kprobe_ftrace_ops __read_mostly = {
.func = kprobe_ftrace_handler,
.flags = FTRACE_OPS_FL_SAVE_REGS,
@@ -964,7 +971,7 @@ static void __kprobes disarm_kprobe_ftrace(struct kprobe *p)
(unsigned long)p->addr, 1, 0);
WARN(ret < 0, "Failed to disarm kprobe-ftrace at %p (%d)\n", p->addr, ret);
}
-#else /* !KPROBES_CAN_USE_FTRACE */
+#else /* !CONFIG_KPROBES_ON_FTRACE */
#define prepare_kprobe(p) arch_prepare_kprobe(p)
#define arm_kprobe_ftrace(p) do {} while (0)
#define disarm_kprobe_ftrace(p) do {} while (0)
@@ -1414,12 +1421,12 @@ static __kprobes int check_kprobe_address_safe(struct kprobe *p,
*/
ftrace_addr = ftrace_location((unsigned long)p->addr);
if (ftrace_addr) {
-#ifdef KPROBES_CAN_USE_FTRACE
+#ifdef CONFIG_KPROBES_ON_FTRACE
/* Given address is not on the instruction boundary */
if ((unsigned long)p->addr != ftrace_addr)
return -EILSEQ;
p->flags |= KPROBE_FLAG_FTRACE;
-#else /* !KPROBES_CAN_USE_FTRACE */
+#else /* !CONFIG_KPROBES_ON_FTRACE */
return -EINVAL;
#endif
}
diff --git a/kernel/module.c b/kernel/module.c
index 250092c1d57..eab08274ec9 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -188,6 +188,7 @@ struct load_info {
ongoing or failed initialization etc. */
static inline int strong_try_module_get(struct module *mod)
{
+ BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED);
if (mod && mod->state == MODULE_STATE_COMING)
return -EBUSY;
if (try_module_get(mod))
@@ -343,6 +344,9 @@ bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
#endif
};
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
+
if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
return true;
}
@@ -450,16 +454,24 @@ const struct kernel_symbol *find_symbol(const char *name,
EXPORT_SYMBOL_GPL(find_symbol);
/* Search for module by name: must hold module_mutex. */
-struct module *find_module(const char *name)
+static struct module *find_module_all(const char *name,
+ bool even_unformed)
{
struct module *mod;
list_for_each_entry(mod, &modules, list) {
+ if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
+ continue;
if (strcmp(mod->name, name) == 0)
return mod;
}
return NULL;
}
+
+struct module *find_module(const char *name)
+{
+ return find_module_all(name, false);
+}
EXPORT_SYMBOL_GPL(find_module);
#ifdef CONFIG_SMP
@@ -525,6 +537,8 @@ bool is_module_percpu_address(unsigned long addr)
preempt_disable();
list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
if (!mod->percpu_size)
continue;
for_each_possible_cpu(cpu) {
@@ -1048,6 +1062,8 @@ static ssize_t show_initstate(struct module_attribute *mattr,
case MODULE_STATE_GOING:
state = "going";
break;
+ default:
+ BUG();
}
return sprintf(buffer, "%s\n", state);
}
@@ -1786,6 +1802,8 @@ void set_all_modules_text_rw(void)
mutex_lock(&module_mutex);
list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
if ((mod->module_core) && (mod->core_text_size)) {
set_page_attributes(mod->module_core,
mod->module_core + mod->core_text_size,
@@ -1807,6 +1825,8 @@ void set_all_modules_text_ro(void)
mutex_lock(&module_mutex);
list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
if ((mod->module_core) && (mod->core_text_size)) {
set_page_attributes(mod->module_core,
mod->module_core + mod->core_text_size,
@@ -2527,6 +2547,13 @@ static int copy_module_from_fd(int fd, struct load_info *info)
err = -EFBIG;
goto out;
}
+
+ /* Don't hand 0 to vmalloc, it whines. */
+ if (stat.size == 0) {
+ err = -EINVAL;
+ goto out;
+ }
+
info->hdr = vmalloc(stat.size);
if (!info->hdr) {
err = -ENOMEM;
@@ -2990,8 +3017,9 @@ static bool finished_loading(const char *name)
bool ret;
mutex_lock(&module_mutex);
- mod = find_module(name);
- ret = !mod || mod->state != MODULE_STATE_COMING;
+ mod = find_module_all(name, true);
+ ret = !mod || mod->state == MODULE_STATE_LIVE
+ || mod->state == MODULE_STATE_GOING;
mutex_unlock(&module_mutex);
return ret;
@@ -3013,6 +3041,12 @@ static int do_init_module(struct module *mod)
{
int ret = 0;
+ /*
+ * We want to find out whether @mod uses async during init. Clear
+ * PF_USED_ASYNC. async_schedule*() will set it.
+ */
+ current->flags &= ~PF_USED_ASYNC;
+
blocking_notifier_call_chain(&module_notify_list,
MODULE_STATE_COMING, mod);
@@ -3058,8 +3092,25 @@ static int do_init_module(struct module *mod)
blocking_notifier_call_chain(&module_notify_list,
MODULE_STATE_LIVE, mod);
- /* We need to finish all async code before the module init sequence is done */
- async_synchronize_full();
+ /*
+ * We need to finish all async code before the module init sequence
+ * is done. This has potential to deadlock. For example, a newly
+ * detected block device can trigger request_module() of the
+ * default iosched from async probing task. Once userland helper
+ * reaches here, async_synchronize_full() will wait on the async
+ * task waiting on request_module() and deadlock.
+ *
+ * This deadlock is avoided by perfomring async_synchronize_full()
+ * iff module init queued any async jobs. This isn't a full
+ * solution as it will deadlock the same if module loading from
+ * async jobs nests more than once; however, due to the various
+ * constraints, this hack seems to be the best option for now.
+ * Please refer to the following thread for details.
+ *
+ * http://thread.gmane.org/gmane.linux.kernel/1420814
+ */
+ if (current->flags & PF_USED_ASYNC)
+ async_synchronize_full();
mutex_lock(&module_mutex);
/* Drop initial reference. */
@@ -3113,6 +3164,32 @@ static int load_module(struct load_info *info, const char __user *uargs,
goto free_copy;
}
+ /*
+ * We try to place it in the list now to make sure it's unique
+ * before we dedicate too many resources. In particular,
+ * temporary percpu memory exhaustion.
+ */
+ mod->state = MODULE_STATE_UNFORMED;
+again:
+ mutex_lock(&module_mutex);
+ if ((old = find_module_all(mod->name, true)) != NULL) {
+ if (old->state == MODULE_STATE_COMING
+ || old->state == MODULE_STATE_UNFORMED) {
+ /* Wait in case it fails to load. */
+ mutex_unlock(&module_mutex);
+ err = wait_event_interruptible(module_wq,
+ finished_loading(mod->name));
+ if (err)
+ goto free_module;
+ goto again;
+ }
+ err = -EEXIST;
+ mutex_unlock(&module_mutex);
+ goto free_module;
+ }
+ list_add_rcu(&mod->list, &modules);
+ mutex_unlock(&module_mutex);
+
#ifdef CONFIG_MODULE_SIG
mod->sig_ok = info->sig_ok;
if (!mod->sig_ok)
@@ -3122,7 +3199,7 @@ static int load_module(struct load_info *info, const char __user *uargs,
/* Now module is in final location, initialize linked lists, etc. */
err = module_unload_init(mod);
if (err)
- goto free_module;
+ goto unlink_mod;
/* Now we've got everything in the final locations, we can
* find optional sections. */
@@ -3157,54 +3234,33 @@ static int load_module(struct load_info *info, const char __user *uargs,
goto free_arch_cleanup;
}
- /* Mark state as coming so strong_try_module_get() ignores us. */
- mod->state = MODULE_STATE_COMING;
-
- /* Now sew it into the lists so we can get lockdep and oops
- * info during argument parsing. No one should access us, since
- * strong_try_module_get() will fail.
- * lockdep/oops can run asynchronous, so use the RCU list insertion
- * function to insert in a way safe to concurrent readers.
- * The mutex protects against concurrent writers.
- */
-again:
- mutex_lock(&module_mutex);
- if ((old = find_module(mod->name)) != NULL) {
- if (old->state == MODULE_STATE_COMING) {
- /* Wait in case it fails to load. */
- mutex_unlock(&module_mutex);
- err = wait_event_interruptible(module_wq,
- finished_loading(mod->name));
- if (err)
- goto free_arch_cleanup;
- goto again;
- }
- err = -EEXIST;
- goto unlock;
- }
-
- /* This has to be done once we're sure module name is unique. */
dynamic_debug_setup(info->debug, info->num_debug);
- /* Find duplicate symbols */
+ mutex_lock(&module_mutex);
+ /* Find duplicate symbols (must be called under lock). */
err = verify_export_symbols(mod);
if (err < 0)
- goto ddebug;
+ goto ddebug_cleanup;
+ /* This relies on module_mutex for list integrity. */
module_bug_finalize(info->hdr, info->sechdrs, mod);
- list_add_rcu(&mod->list, &modules);
+
+ /* Mark state as coming so strong_try_module_get() ignores us,
+ * but kallsyms etc. can see us. */
+ mod->state = MODULE_STATE_COMING;
+
mutex_unlock(&module_mutex);
/* Module is ready to execute: parsing args may do that. */
err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
-32768, 32767, &ddebug_dyndbg_module_param_cb);
if (err < 0)
- goto unlink;
+ goto bug_cleanup;
/* Link in to syfs. */
err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
if (err < 0)
- goto unlink;
+ goto bug_cleanup;
/* Get rid of temporary copy. */
free_copy(info);
@@ -3214,16 +3270,13 @@ again:
return do_init_module(mod);
- unlink:
+ bug_cleanup:
+ /* module_bug_cleanup needs module_mutex protection */
mutex_lock(&module_mutex);
- /* Unlink carefully: kallsyms could be walking list. */
- list_del_rcu(&mod->list);
module_bug_cleanup(mod);
- wake_up_all(&module_wq);
- ddebug:
- dynamic_debug_remove(info->debug);
- unlock:
+ ddebug_cleanup:
mutex_unlock(&module_mutex);
+ dynamic_debug_remove(info->debug);
synchronize_sched();
kfree(mod->args);
free_arch_cleanup:
@@ -3232,6 +3285,12 @@ again:
free_modinfo(mod);
free_unload:
module_unload_free(mod);
+ unlink_mod:
+ mutex_lock(&module_mutex);
+ /* Unlink carefully: kallsyms could be walking list. */
+ list_del_rcu(&mod->list);
+ wake_up_all(&module_wq);
+ mutex_unlock(&module_mutex);
free_module:
module_deallocate(mod, info);
free_copy:
@@ -3354,6 +3413,8 @@ const char *module_address_lookup(unsigned long addr,
preempt_disable();
list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
if (within_module_init(addr, mod) ||
within_module_core(addr, mod)) {
if (modname)
@@ -3377,6 +3438,8 @@ int lookup_module_symbol_name(unsigned long addr, char *symname)
preempt_disable();
list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
if (within_module_init(addr, mod) ||
within_module_core(addr, mod)) {
const char *sym;
@@ -3401,6 +3464,8 @@ int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
preempt_disable();
list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
if (within_module_init(addr, mod) ||
within_module_core(addr, mod)) {
const char *sym;
@@ -3428,6 +3493,8 @@ int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
preempt_disable();
list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
if (symnum < mod->num_symtab) {
*value = mod->symtab[symnum].st_value;
*type = mod->symtab[symnum].st_info;
@@ -3470,9 +3537,12 @@ unsigned long module_kallsyms_lookup_name(const char *name)
ret = mod_find_symname(mod, colon+1);
*colon = ':';
} else {
- list_for_each_entry_rcu(mod, &modules, list)
+ list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
if ((ret = mod_find_symname(mod, name)) != 0)
break;
+ }
}
preempt_enable();
return ret;
@@ -3487,6 +3557,8 @@ int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
int ret;
list_for_each_entry(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
for (i = 0; i < mod->num_symtab; i++) {
ret = fn(data, mod->strtab + mod->symtab[i].st_name,
mod, mod->symtab[i].st_value);
@@ -3502,6 +3574,7 @@ static char *module_flags(struct module *mod, char *buf)
{
int bx = 0;
+ BUG_ON(mod->state == MODULE_STATE_UNFORMED);
if (mod->taints ||
mod->state == MODULE_STATE_GOING ||
mod->state == MODULE_STATE_COMING) {
@@ -3543,6 +3616,10 @@ static int m_show(struct seq_file *m, void *p)
struct module *mod = list_entry(p, struct module, list);
char buf[8];
+ /* We always ignore unformed modules. */
+ if (mod->state == MODULE_STATE_UNFORMED)
+ return 0;
+
seq_printf(m, "%s %u",
mod->name, mod->init_size + mod->core_size);
print_unload_info(m, mod);
@@ -3603,6 +3680,8 @@ const struct exception_table_entry *search_module_extables(unsigned long addr)
preempt_disable();
list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
if (mod->num_exentries == 0)
continue;
@@ -3651,10 +3730,13 @@ struct module *__module_address(unsigned long addr)
if (addr < module_addr_min || addr > module_addr_max)
return NULL;
- list_for_each_entry_rcu(mod, &modules, list)
+ list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
if (within_module_core(addr, mod)
|| within_module_init(addr, mod))
return mod;
+ }
return NULL;
}
EXPORT_SYMBOL_GPL(__module_address);
@@ -3707,8 +3789,11 @@ void print_modules(void)
printk(KERN_DEFAULT "Modules linked in:");
/* Most callers should already have preempt disabled, but make sure */
preempt_disable();
- list_for_each_entry_rcu(mod, &modules, list)
+ list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
printk(" %s%s", mod->name, module_flags(mod, buf));
+ }
preempt_enable();
if (last_unloaded_module[0])
printk(" [last unloaded: %s]", last_unloaded_module);
diff --git a/kernel/mutex.c b/kernel/mutex.c
index a307cc9c952..52f23011b6e 100644
--- a/kernel/mutex.c
+++ b/kernel/mutex.c
@@ -19,6 +19,7 @@
*/
#include <linux/mutex.h>
#include <linux/sched.h>
+#include <linux/sched/rt.h>
#include <linux/export.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
diff --git a/kernel/pid.c b/kernel/pid.c
index de9af600006..f2c6a682509 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -331,7 +331,7 @@ out:
return pid;
out_unlock:
- spin_unlock(&pidmap_lock);
+ spin_unlock_irq(&pidmap_lock);
out_free:
while (++i <= ns->level)
free_pidmap(pid->numbers + i);
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index a278cad1d5d..8fd709c9bb5 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -155,11 +155,19 @@ static void bump_cpu_timer(struct k_itimer *timer,
static inline cputime_t prof_ticks(struct task_struct *p)
{
- return p->utime + p->stime;
+ cputime_t utime, stime;
+
+ task_cputime(p, &utime, &stime);
+
+ return utime + stime;
}
static inline cputime_t virt_ticks(struct task_struct *p)
{
- return p->utime;
+ cputime_t utime;
+
+ task_cputime(p, &utime, NULL);
+
+ return utime;
}
static int
@@ -471,18 +479,23 @@ static void cleanup_timers(struct list_head *head,
*/
void posix_cpu_timers_exit(struct task_struct *tsk)
{
+ cputime_t utime, stime;
+
add_device_randomness((const void*) &tsk->se.sum_exec_runtime,
sizeof(unsigned long long));
+ task_cputime(tsk, &utime, &stime);
cleanup_timers(tsk->cpu_timers,
- tsk->utime, tsk->stime, tsk->se.sum_exec_runtime);
+ utime, stime, tsk->se.sum_exec_runtime);
}
void posix_cpu_timers_exit_group(struct task_struct *tsk)
{
struct signal_struct *const sig = tsk->signal;
+ cputime_t utime, stime;
+ task_cputime(tsk, &utime, &stime);
cleanup_timers(tsk->signal->cpu_timers,
- tsk->utime + sig->utime, tsk->stime + sig->stime,
+ utime + sig->utime, stime + sig->stime,
tsk->se.sum_exec_runtime + sig->sum_sched_runtime);
}
@@ -1226,11 +1239,14 @@ static inline int task_cputime_expired(const struct task_cputime *sample,
static inline int fastpath_timer_check(struct task_struct *tsk)
{
struct signal_struct *sig;
+ cputime_t utime, stime;
+
+ task_cputime(tsk, &utime, &stime);
if (!task_cputime_zero(&tsk->cputime_expires)) {
struct task_cputime task_sample = {
- .utime = tsk->utime,
- .stime = tsk->stime,
+ .utime = utime,
+ .stime = stime,
.sum_exec_runtime = tsk->se.sum_exec_runtime
};
@@ -1401,8 +1417,10 @@ static int do_cpu_nanosleep(const clockid_t which_clock, int flags,
while (!signal_pending(current)) {
if (timer.it.cpu.expires.sched == 0) {
/*
- * Our timer fired and was reset.
+ * Our timer fired and was reset, below
+ * deletion can not fail.
*/
+ posix_cpu_timer_del(&timer);
spin_unlock_irq(&timer.it_lock);
return 0;
}
@@ -1420,9 +1438,26 @@ static int do_cpu_nanosleep(const clockid_t which_clock, int flags,
* We were interrupted by a signal.
*/
sample_to_timespec(which_clock, timer.it.cpu.expires, rqtp);
- posix_cpu_timer_set(&timer, 0, &zero_it, it);
+ error = posix_cpu_timer_set(&timer, 0, &zero_it, it);
+ if (!error) {
+ /*
+ * Timer is now unarmed, deletion can not fail.
+ */
+ posix_cpu_timer_del(&timer);
+ }
spin_unlock_irq(&timer.it_lock);
+ while (error == TIMER_RETRY) {
+ /*
+ * We need to handle case when timer was or is in the
+ * middle of firing. In other cases we already freed
+ * resources.
+ */
+ spin_lock_irq(&timer.it_lock);
+ error = posix_cpu_timer_del(&timer);
+ spin_unlock_irq(&timer.it_lock);
+ }
+
if ((it->it_value.tv_sec | it->it_value.tv_nsec) == 0) {
/*
* It actually did fire already.
diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c
index 69185ae6b70..10349d5f2ec 100644
--- a/kernel/posix-timers.c
+++ b/kernel/posix-timers.c
@@ -997,7 +997,7 @@ SYSCALL_DEFINE2(clock_adjtime, const clockid_t, which_clock,
err = kc->clock_adj(which_clock, &ktx);
- if (!err && copy_to_user(utx, &ktx, sizeof(ktx)))
+ if (err >= 0 && copy_to_user(utx, &ktx, sizeof(ktx)))
return -EFAULT;
return err;
diff --git a/kernel/printk.c b/kernel/printk.c
index 19c0d7bcf24..f24633afa46 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -42,6 +42,7 @@
#include <linux/notifier.h>
#include <linux/rculist.h>
#include <linux/poll.h>
+#include <linux/irq_work.h>
#include <asm/uaccess.h>
@@ -87,12 +88,6 @@ static DEFINE_SEMAPHORE(console_sem);
struct console *console_drivers;
EXPORT_SYMBOL_GPL(console_drivers);
-#ifdef CONFIG_LOCKDEP
-static struct lockdep_map console_lock_dep_map = {
- .name = "console_lock"
-};
-#endif
-
/*
* This is used for debugging the mess that is the VT code by
* keeping track if we have the console semaphore held. It's
@@ -870,10 +865,11 @@ static size_t print_time(u64 ts, char *buf)
if (!printk_time)
return 0;
+ rem_nsec = do_div(ts, 1000000000);
+
if (!buf)
- return 15;
+ return snprintf(NULL, 0, "[%5lu.000000] ", (unsigned long)ts);
- rem_nsec = do_div(ts, 1000000000);
return sprintf(buf, "[%5lu.%06lu] ",
(unsigned long)ts, rem_nsec / 1000);
}
@@ -1923,7 +1919,6 @@ void console_lock(void)
return;
console_locked = 1;
console_may_schedule = 1;
- mutex_acquire(&console_lock_dep_map, 0, 0, _RET_IP_);
}
EXPORT_SYMBOL(console_lock);
@@ -1945,7 +1940,6 @@ int console_trylock(void)
}
console_locked = 1;
console_may_schedule = 0;
- mutex_acquire(&console_lock_dep_map, 0, 1, _RET_IP_);
return 1;
}
EXPORT_SYMBOL(console_trylock);
@@ -1966,30 +1960,32 @@ int is_console_locked(void)
static DEFINE_PER_CPU(int, printk_pending);
static DEFINE_PER_CPU(char [PRINTK_BUF_SIZE], printk_sched_buf);
-void printk_tick(void)
+static void wake_up_klogd_work_func(struct irq_work *irq_work)
{
- if (__this_cpu_read(printk_pending)) {
- int pending = __this_cpu_xchg(printk_pending, 0);
- if (pending & PRINTK_PENDING_SCHED) {
- char *buf = __get_cpu_var(printk_sched_buf);
- printk(KERN_WARNING "[sched_delayed] %s", buf);
- }
- if (pending & PRINTK_PENDING_WAKEUP)
- wake_up_interruptible(&log_wait);
+ int pending = __this_cpu_xchg(printk_pending, 0);
+
+ if (pending & PRINTK_PENDING_SCHED) {
+ char *buf = __get_cpu_var(printk_sched_buf);
+ printk(KERN_WARNING "[sched_delayed] %s", buf);
}
-}
-int printk_needs_cpu(int cpu)
-{
- if (cpu_is_offline(cpu))
- printk_tick();
- return __this_cpu_read(printk_pending);
+ if (pending & PRINTK_PENDING_WAKEUP)
+ wake_up_interruptible(&log_wait);
}
+static DEFINE_PER_CPU(struct irq_work, wake_up_klogd_work) = {
+ .func = wake_up_klogd_work_func,
+ .flags = IRQ_WORK_LAZY,
+};
+
void wake_up_klogd(void)
{
- if (waitqueue_active(&log_wait))
+ preempt_disable();
+ if (waitqueue_active(&log_wait)) {
this_cpu_or(printk_pending, PRINTK_PENDING_WAKEUP);
+ irq_work_queue(&__get_cpu_var(wake_up_klogd_work));
+ }
+ preempt_enable();
}
static void console_cont_flush(char *text, size_t size)
@@ -2106,7 +2102,6 @@ skip:
local_irq_restore(flags);
}
console_locked = 0;
- mutex_release(&console_lock_dep_map, 1, _RET_IP_);
/* Release the exclusive_console once it is used */
if (unlikely(exclusive_console))
@@ -2470,6 +2465,7 @@ int printk_sched(const char *fmt, ...)
va_end(args);
__this_cpu_or(printk_pending, PRINTK_PENDING_SCHED);
+ irq_work_queue(&__get_cpu_var(wake_up_klogd_work));
local_irq_restore(flags);
return r;
diff --git a/kernel/profile.c b/kernel/profile.c
index 1f391819c42..dc3384ee874 100644
--- a/kernel/profile.c
+++ b/kernel/profile.c
@@ -37,9 +37,6 @@ struct profile_hit {
#define NR_PROFILE_HIT (PAGE_SIZE/sizeof(struct profile_hit))
#define NR_PROFILE_GRP (NR_PROFILE_HIT/PROFILE_GRPSZ)
-/* Oprofile timer tick hook */
-static int (*timer_hook)(struct pt_regs *) __read_mostly;
-
static atomic_t *prof_buffer;
static unsigned long prof_len, prof_shift;
@@ -208,25 +205,6 @@ int profile_event_unregister(enum profile_type type, struct notifier_block *n)
}
EXPORT_SYMBOL_GPL(profile_event_unregister);
-int register_timer_hook(int (*hook)(struct pt_regs *))
-{
- if (timer_hook)
- return -EBUSY;
- timer_hook = hook;
- return 0;
-}
-EXPORT_SYMBOL_GPL(register_timer_hook);
-
-void unregister_timer_hook(int (*hook)(struct pt_regs *))
-{
- WARN_ON(hook != timer_hook);
- timer_hook = NULL;
- /* make sure all CPUs see the NULL hook */
- synchronize_sched(); /* Allow ongoing interrupts to complete. */
-}
-EXPORT_SYMBOL_GPL(unregister_timer_hook);
-
-
#ifdef CONFIG_SMP
/*
* Each cpu has a pair of open-addressed hashtables for pending
@@ -436,8 +414,6 @@ void profile_tick(int type)
{
struct pt_regs *regs = get_irq_regs();
- if (type == CPU_PROFILING && timer_hook)
- timer_hook(regs);
if (!user_mode(regs) && prof_cpu_mask != NULL &&
cpumask_test_cpu(smp_processor_id(), prof_cpu_mask))
profile_hit(type, (void *)profile_pc(regs));
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 1599157336a..acbd28424d8 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -117,11 +117,45 @@ void __ptrace_unlink(struct task_struct *child)
* TASK_KILLABLE sleeps.
*/
if (child->jobctl & JOBCTL_STOP_PENDING || task_is_traced(child))
- signal_wake_up(child, task_is_traced(child));
+ ptrace_signal_wake_up(child, true);
spin_unlock(&child->sighand->siglock);
}
+/* Ensure that nothing can wake it up, even SIGKILL */
+static bool ptrace_freeze_traced(struct task_struct *task)
+{
+ bool ret = false;
+
+ /* Lockless, nobody but us can set this flag */
+ if (task->jobctl & JOBCTL_LISTENING)
+ return ret;
+
+ spin_lock_irq(&task->sighand->siglock);
+ if (task_is_traced(task) && !__fatal_signal_pending(task)) {
+ task->state = __TASK_TRACED;
+ ret = true;
+ }
+ spin_unlock_irq(&task->sighand->siglock);
+
+ return ret;
+}
+
+static void ptrace_unfreeze_traced(struct task_struct *task)
+{
+ if (task->state != __TASK_TRACED)
+ return;
+
+ WARN_ON(!task->ptrace || task->parent != current);
+
+ spin_lock_irq(&task->sighand->siglock);
+ if (__fatal_signal_pending(task))
+ wake_up_state(task, __TASK_TRACED);
+ else
+ task->state = TASK_TRACED;
+ spin_unlock_irq(&task->sighand->siglock);
+}
+
/**
* ptrace_check_attach - check whether ptracee is ready for ptrace operation
* @child: ptracee to check for
@@ -139,7 +173,7 @@ void __ptrace_unlink(struct task_struct *child)
* RETURNS:
* 0 on success, -ESRCH if %child is not ready.
*/
-int ptrace_check_attach(struct task_struct *child, bool ignore_state)
+static int ptrace_check_attach(struct task_struct *child, bool ignore_state)
{
int ret = -ESRCH;
@@ -151,24 +185,29 @@ int ptrace_check_attach(struct task_struct *child, bool ignore_state)
* be changed by us so it's not changing right after this.
*/
read_lock(&tasklist_lock);
- if ((child->ptrace & PT_PTRACED) && child->parent == current) {
+ if (child->ptrace && child->parent == current) {
+ WARN_ON(child->state == __TASK_TRACED);
/*
* child->sighand can't be NULL, release_task()
* does ptrace_unlink() before __exit_signal().
*/
- spin_lock_irq(&child->sighand->siglock);
- WARN_ON_ONCE(task_is_stopped(child));
- if (ignore_state || (task_is_traced(child) &&
- !(child->jobctl & JOBCTL_LISTENING)))
+ if (ignore_state || ptrace_freeze_traced(child))
ret = 0;
- spin_unlock_irq(&child->sighand->siglock);
}
read_unlock(&tasklist_lock);
- if (!ret && !ignore_state)
- ret = wait_task_inactive(child, TASK_TRACED) ? 0 : -ESRCH;
+ if (!ret && !ignore_state) {
+ if (!wait_task_inactive(child, __TASK_TRACED)) {
+ /*
+ * This can only happen if may_ptrace_stop() fails and
+ * ptrace_stop() changes ->state back to TASK_RUNNING,
+ * so we should not worry about leaking __TASK_TRACED.
+ */
+ WARN_ON(child->state == __TASK_TRACED);
+ ret = -ESRCH;
+ }
+ }
- /* All systems go.. */
return ret;
}
@@ -317,7 +356,7 @@ static int ptrace_attach(struct task_struct *task, long request,
*/
if (task_is_stopped(task) &&
task_set_jobctl_pending(task, JOBCTL_TRAP_STOP | JOBCTL_TRAPPING))
- signal_wake_up(task, 1);
+ signal_wake_up_state(task, __TASK_STOPPED);
spin_unlock(&task->sighand->siglock);
@@ -673,6 +712,12 @@ static int ptrace_regset(struct task_struct *task, int req, unsigned int type,
kiov->iov_len, kiov->iov_base);
}
+/*
+ * This is declared in linux/regset.h and defined in machine-dependent
+ * code. We put the export here, near the primary machine-neutral use,
+ * to ensure no machine forgets it.
+ */
+EXPORT_SYMBOL_GPL(task_user_regset_view);
#endif
int ptrace_request(struct task_struct *child, long request,
@@ -737,7 +782,7 @@ int ptrace_request(struct task_struct *child, long request,
* tracee into STOP.
*/
if (likely(task_set_jobctl_pending(child, JOBCTL_TRAP_STOP)))
- signal_wake_up(child, child->jobctl & JOBCTL_LISTENING);
+ ptrace_signal_wake_up(child, child->jobctl & JOBCTL_LISTENING);
unlock_task_sighand(child, &flags);
ret = 0;
@@ -763,7 +808,7 @@ int ptrace_request(struct task_struct *child, long request,
* start of this trap and now. Trigger re-trap.
*/
if (child->jobctl & JOBCTL_TRAP_NOTIFY)
- signal_wake_up(child, true);
+ ptrace_signal_wake_up(child, true);
ret = 0;
}
unlock_task_sighand(child, &flags);
@@ -900,6 +945,8 @@ SYSCALL_DEFINE4(ptrace, long, request, long, pid, unsigned long, addr,
goto out_put_task_struct;
ret = arch_ptrace(child, request, addr, data);
+ if (ret || request != PTRACE_DETACH)
+ ptrace_unfreeze_traced(child);
out_put_task_struct:
put_task_struct(child);
@@ -1039,8 +1086,11 @@ asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid,
ret = ptrace_check_attach(child, request == PTRACE_KILL ||
request == PTRACE_INTERRUPT);
- if (!ret)
+ if (!ret) {
ret = compat_arch_ptrace(child, request, addr, data);
+ if (ret || request != PTRACE_DETACH)
+ ptrace_unfreeze_traced(child);
+ }
out_put_task_struct:
put_task_struct(child);
diff --git a/kernel/rcu.h b/kernel/rcu.h
index 20dfba576c2..7f8e7590e3e 100644
--- a/kernel/rcu.h
+++ b/kernel/rcu.h
@@ -111,4 +111,11 @@ static inline bool __rcu_reclaim(char *rn, struct rcu_head *head)
extern int rcu_expedited;
+#ifdef CONFIG_RCU_STALL_COMMON
+
+extern int rcu_cpu_stall_suppress;
+int rcu_jiffies_till_stall_check(void);
+
+#endif /* #ifdef CONFIG_RCU_STALL_COMMON */
+
#endif /* __LINUX_RCU_H */
diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c
index a2cf76177b4..48ab70384a4 100644
--- a/kernel/rcupdate.c
+++ b/kernel/rcupdate.c
@@ -404,11 +404,65 @@ EXPORT_SYMBOL_GPL(rcuhead_debug_descr);
#endif /* #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */
#if defined(CONFIG_TREE_RCU) || defined(CONFIG_TREE_PREEMPT_RCU) || defined(CONFIG_RCU_TRACE)
-void do_trace_rcu_torture_read(char *rcutorturename, struct rcu_head *rhp)
+void do_trace_rcu_torture_read(char *rcutorturename, struct rcu_head *rhp,
+ unsigned long secs,
+ unsigned long c_old, unsigned long c)
{
- trace_rcu_torture_read(rcutorturename, rhp);
+ trace_rcu_torture_read(rcutorturename, rhp, secs, c_old, c);
}
EXPORT_SYMBOL_GPL(do_trace_rcu_torture_read);
#else
-#define do_trace_rcu_torture_read(rcutorturename, rhp) do { } while (0)
+#define do_trace_rcu_torture_read(rcutorturename, rhp, secs, c_old, c) \
+ do { } while (0)
#endif
+
+#ifdef CONFIG_RCU_STALL_COMMON
+
+#ifdef CONFIG_PROVE_RCU
+#define RCU_STALL_DELAY_DELTA (5 * HZ)
+#else
+#define RCU_STALL_DELAY_DELTA 0
+#endif
+
+int rcu_cpu_stall_suppress __read_mostly; /* 1 = suppress stall warnings. */
+int rcu_cpu_stall_timeout __read_mostly = CONFIG_RCU_CPU_STALL_TIMEOUT;
+
+module_param(rcu_cpu_stall_suppress, int, 0644);
+module_param(rcu_cpu_stall_timeout, int, 0644);
+
+int rcu_jiffies_till_stall_check(void)
+{
+ int till_stall_check = ACCESS_ONCE(rcu_cpu_stall_timeout);
+
+ /*
+ * Limit check must be consistent with the Kconfig limits
+ * for CONFIG_RCU_CPU_STALL_TIMEOUT.
+ */
+ if (till_stall_check < 3) {
+ ACCESS_ONCE(rcu_cpu_stall_timeout) = 3;
+ till_stall_check = 3;
+ } else if (till_stall_check > 300) {
+ ACCESS_ONCE(rcu_cpu_stall_timeout) = 300;
+ till_stall_check = 300;
+ }
+ return till_stall_check * HZ + RCU_STALL_DELAY_DELTA;
+}
+
+static int rcu_panic(struct notifier_block *this, unsigned long ev, void *ptr)
+{
+ rcu_cpu_stall_suppress = 1;
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block rcu_panic_block = {
+ .notifier_call = rcu_panic,
+};
+
+static int __init check_cpu_stall_init(void)
+{
+ atomic_notifier_chain_register(&panic_notifier_list, &rcu_panic_block);
+ return 0;
+}
+early_initcall(check_cpu_stall_init);
+
+#endif /* #ifdef CONFIG_RCU_STALL_COMMON */
diff --git a/kernel/rcutiny.c b/kernel/rcutiny.c
index e7dce58f9c2..a0714a51b6d 100644
--- a/kernel/rcutiny.c
+++ b/kernel/rcutiny.c
@@ -51,10 +51,10 @@ static void __call_rcu(struct rcu_head *head,
void (*func)(struct rcu_head *rcu),
struct rcu_ctrlblk *rcp);
-#include "rcutiny_plugin.h"
-
static long long rcu_dynticks_nesting = DYNTICK_TASK_EXIT_IDLE;
+#include "rcutiny_plugin.h"
+
/* Common code for rcu_idle_enter() and rcu_irq_exit(), see kernel/rcutree.c. */
static void rcu_idle_enter_common(long long newval)
{
@@ -193,7 +193,7 @@ EXPORT_SYMBOL(rcu_is_cpu_idle);
* interrupts don't count, we must be running at the first interrupt
* level.
*/
-int rcu_is_cpu_rrupt_from_idle(void)
+static int rcu_is_cpu_rrupt_from_idle(void)
{
return rcu_dynticks_nesting <= 1;
}
@@ -205,6 +205,7 @@ int rcu_is_cpu_rrupt_from_idle(void)
*/
static int rcu_qsctr_help(struct rcu_ctrlblk *rcp)
{
+ reset_cpu_stall_ticks(rcp);
if (rcp->rcucblist != NULL &&
rcp->donetail != rcp->curtail) {
rcp->donetail = rcp->curtail;
@@ -251,6 +252,7 @@ void rcu_bh_qs(int cpu)
*/
void rcu_check_callbacks(int cpu, int user)
{
+ check_cpu_stalls();
if (user || rcu_is_cpu_rrupt_from_idle())
rcu_sched_qs(cpu);
else if (!in_softirq())
diff --git a/kernel/rcutiny_plugin.h b/kernel/rcutiny_plugin.h
index f85016a2309..8a233002fae 100644
--- a/kernel/rcutiny_plugin.h
+++ b/kernel/rcutiny_plugin.h
@@ -33,6 +33,9 @@ struct rcu_ctrlblk {
struct rcu_head **donetail; /* ->next pointer of last "done" CB. */
struct rcu_head **curtail; /* ->next pointer of last CB. */
RCU_TRACE(long qlen); /* Number of pending CBs. */
+ RCU_TRACE(unsigned long gp_start); /* Start time for stalls. */
+ RCU_TRACE(unsigned long ticks_this_gp); /* Statistic for stalls. */
+ RCU_TRACE(unsigned long jiffies_stall); /* Jiffies at next stall. */
RCU_TRACE(char *name); /* Name of RCU type. */
};
@@ -54,6 +57,51 @@ int rcu_scheduler_active __read_mostly;
EXPORT_SYMBOL_GPL(rcu_scheduler_active);
#endif /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
+#ifdef CONFIG_RCU_TRACE
+
+static void check_cpu_stall(struct rcu_ctrlblk *rcp)
+{
+ unsigned long j;
+ unsigned long js;
+
+ if (rcu_cpu_stall_suppress)
+ return;
+ rcp->ticks_this_gp++;
+ j = jiffies;
+ js = rcp->jiffies_stall;
+ if (*rcp->curtail && ULONG_CMP_GE(j, js)) {
+ pr_err("INFO: %s stall on CPU (%lu ticks this GP) idle=%llx (t=%lu jiffies q=%ld)\n",
+ rcp->name, rcp->ticks_this_gp, rcu_dynticks_nesting,
+ jiffies - rcp->gp_start, rcp->qlen);
+ dump_stack();
+ }
+ if (*rcp->curtail && ULONG_CMP_GE(j, js))
+ rcp->jiffies_stall = jiffies +
+ 3 * rcu_jiffies_till_stall_check() + 3;
+ else if (ULONG_CMP_GE(j, js))
+ rcp->jiffies_stall = jiffies + rcu_jiffies_till_stall_check();
+}
+
+static void check_cpu_stall_preempt(void);
+
+#endif /* #ifdef CONFIG_RCU_TRACE */
+
+static void reset_cpu_stall_ticks(struct rcu_ctrlblk *rcp)
+{
+#ifdef CONFIG_RCU_TRACE
+ rcp->ticks_this_gp = 0;
+ rcp->gp_start = jiffies;
+ rcp->jiffies_stall = jiffies + rcu_jiffies_till_stall_check();
+#endif /* #ifdef CONFIG_RCU_TRACE */
+}
+
+static void check_cpu_stalls(void)
+{
+ RCU_TRACE(check_cpu_stall(&rcu_bh_ctrlblk));
+ RCU_TRACE(check_cpu_stall(&rcu_sched_ctrlblk));
+ RCU_TRACE(check_cpu_stall_preempt());
+}
+
#ifdef CONFIG_TINY_PREEMPT_RCU
#include <linux/delay.h>
@@ -448,6 +496,7 @@ static void rcu_preempt_start_gp(void)
/* Official start of GP. */
rcu_preempt_ctrlblk.gpnum++;
RCU_TRACE(rcu_preempt_ctrlblk.n_grace_periods++);
+ reset_cpu_stall_ticks(&rcu_preempt_ctrlblk.rcb);
/* Any blocked RCU readers block new GP. */
if (rcu_preempt_blocked_readers_any())
@@ -1054,4 +1103,11 @@ MODULE_AUTHOR("Paul E. McKenney");
MODULE_DESCRIPTION("Read-Copy Update tracing for tiny implementation");
MODULE_LICENSE("GPL");
+static void check_cpu_stall_preempt(void)
+{
+#ifdef CONFIG_TINY_PREEMPT_RCU
+ check_cpu_stall(&rcu_preempt_ctrlblk.rcb);
+#endif /* #ifdef CONFIG_TINY_PREEMPT_RCU */
+}
+
#endif /* #ifdef CONFIG_RCU_TRACE */
diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c
index 31dea01c85f..e1f3a8c9672 100644
--- a/kernel/rcutorture.c
+++ b/kernel/rcutorture.c
@@ -46,6 +46,7 @@
#include <linux/stat.h>
#include <linux/srcu.h>
#include <linux/slab.h>
+#include <linux/trace_clock.h>
#include <asm/byteorder.h>
MODULE_LICENSE("GPL");
@@ -207,6 +208,20 @@ MODULE_PARM_DESC(rcutorture_runnable, "Start rcutorture at boot");
#define rcu_can_boost() 0
#endif /* #else #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */
+#ifdef CONFIG_RCU_TRACE
+static u64 notrace rcu_trace_clock_local(void)
+{
+ u64 ts = trace_clock_local();
+ unsigned long __maybe_unused ts_rem = do_div(ts, NSEC_PER_USEC);
+ return ts;
+}
+#else /* #ifdef CONFIG_RCU_TRACE */
+static u64 notrace rcu_trace_clock_local(void)
+{
+ return 0ULL;
+}
+#endif /* #else #ifdef CONFIG_RCU_TRACE */
+
static unsigned long shutdown_time; /* jiffies to system shutdown. */
static unsigned long boost_starttime; /* jiffies of next boost test start. */
DEFINE_MUTEX(boost_mutex); /* protect setting boost_starttime */
@@ -845,7 +860,7 @@ static int rcu_torture_boost(void *arg)
/* Wait for the next test interval. */
oldstarttime = boost_starttime;
while (ULONG_CMP_LT(jiffies, oldstarttime)) {
- schedule_timeout_uninterruptible(1);
+ schedule_timeout_interruptible(oldstarttime - jiffies);
rcu_stutter_wait("rcu_torture_boost");
if (kthread_should_stop() ||
fullstop != FULLSTOP_DONTSTOP)
@@ -1028,7 +1043,6 @@ void rcutorture_trace_dump(void)
return;
if (atomic_xchg(&beenhere, 1) != 0)
return;
- do_trace_rcu_torture_read(cur_ops->name, (struct rcu_head *)~0UL);
ftrace_dump(DUMP_ALL);
}
@@ -1042,13 +1056,16 @@ static void rcu_torture_timer(unsigned long unused)
{
int idx;
int completed;
+ int completed_end;
static DEFINE_RCU_RANDOM(rand);
static DEFINE_SPINLOCK(rand_lock);
struct rcu_torture *p;
int pipe_count;
+ unsigned long long ts;
idx = cur_ops->readlock();
completed = cur_ops->completed();
+ ts = rcu_trace_clock_local();
p = rcu_dereference_check(rcu_torture_current,
rcu_read_lock_bh_held() ||
rcu_read_lock_sched_held() ||
@@ -1058,7 +1075,6 @@ static void rcu_torture_timer(unsigned long unused)
cur_ops->readunlock(idx);
return;
}
- do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu);
if (p->rtort_mbtest == 0)
atomic_inc(&n_rcu_torture_mberror);
spin_lock(&rand_lock);
@@ -1071,10 +1087,14 @@ static void rcu_torture_timer(unsigned long unused)
/* Should not happen, but... */
pipe_count = RCU_TORTURE_PIPE_LEN;
}
- if (pipe_count > 1)
+ completed_end = cur_ops->completed();
+ if (pipe_count > 1) {
+ do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu, ts,
+ completed, completed_end);
rcutorture_trace_dump();
+ }
__this_cpu_inc(rcu_torture_count[pipe_count]);
- completed = cur_ops->completed() - completed;
+ completed = completed_end - completed;
if (completed > RCU_TORTURE_PIPE_LEN) {
/* Should not happen, but... */
completed = RCU_TORTURE_PIPE_LEN;
@@ -1094,11 +1114,13 @@ static int
rcu_torture_reader(void *arg)
{
int completed;
+ int completed_end;
int idx;
DEFINE_RCU_RANDOM(rand);
struct rcu_torture *p;
int pipe_count;
struct timer_list t;
+ unsigned long long ts;
VERBOSE_PRINTK_STRING("rcu_torture_reader task started");
set_user_nice(current, 19);
@@ -1112,6 +1134,7 @@ rcu_torture_reader(void *arg)
}
idx = cur_ops->readlock();
completed = cur_ops->completed();
+ ts = rcu_trace_clock_local();
p = rcu_dereference_check(rcu_torture_current,
rcu_read_lock_bh_held() ||
rcu_read_lock_sched_held() ||
@@ -1122,7 +1145,6 @@ rcu_torture_reader(void *arg)
schedule_timeout_interruptible(HZ);
continue;
}
- do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu);
if (p->rtort_mbtest == 0)
atomic_inc(&n_rcu_torture_mberror);
cur_ops->read_delay(&rand);
@@ -1132,10 +1154,14 @@ rcu_torture_reader(void *arg)
/* Should not happen, but... */
pipe_count = RCU_TORTURE_PIPE_LEN;
}
- if (pipe_count > 1)
+ completed_end = cur_ops->completed();
+ if (pipe_count > 1) {
+ do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu,
+ ts, completed, completed_end);
rcutorture_trace_dump();
+ }
__this_cpu_inc(rcu_torture_count[pipe_count]);
- completed = cur_ops->completed() - completed;
+ completed = completed_end - completed;
if (completed > RCU_TORTURE_PIPE_LEN) {
/* Should not happen, but... */
completed = RCU_TORTURE_PIPE_LEN;
@@ -1301,19 +1327,35 @@ static void rcu_torture_shuffle_tasks(void)
set_cpus_allowed_ptr(reader_tasks[i],
shuffle_tmp_mask);
}
-
if (fakewriter_tasks) {
for (i = 0; i < nfakewriters; i++)
if (fakewriter_tasks[i])
set_cpus_allowed_ptr(fakewriter_tasks[i],
shuffle_tmp_mask);
}
-
if (writer_task)
set_cpus_allowed_ptr(writer_task, shuffle_tmp_mask);
-
if (stats_task)
set_cpus_allowed_ptr(stats_task, shuffle_tmp_mask);
+ if (stutter_task)
+ set_cpus_allowed_ptr(stutter_task, shuffle_tmp_mask);
+ if (fqs_task)
+ set_cpus_allowed_ptr(fqs_task, shuffle_tmp_mask);
+ if (shutdown_task)
+ set_cpus_allowed_ptr(shutdown_task, shuffle_tmp_mask);
+#ifdef CONFIG_HOTPLUG_CPU
+ if (onoff_task)
+ set_cpus_allowed_ptr(onoff_task, shuffle_tmp_mask);
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+ if (stall_task)
+ set_cpus_allowed_ptr(stall_task, shuffle_tmp_mask);
+ if (barrier_cbs_tasks)
+ for (i = 0; i < n_barrier_cbs; i++)
+ if (barrier_cbs_tasks[i])
+ set_cpus_allowed_ptr(barrier_cbs_tasks[i],
+ shuffle_tmp_mask);
+ if (barrier_task)
+ set_cpus_allowed_ptr(barrier_task, shuffle_tmp_mask);
if (rcu_idle_cpu == -1)
rcu_idle_cpu = num_online_cpus() - 1;
@@ -1749,7 +1791,7 @@ static int rcu_torture_barrier_init(void)
barrier_cbs_wq =
kzalloc(n_barrier_cbs * sizeof(barrier_cbs_wq[0]),
GFP_KERNEL);
- if (barrier_cbs_tasks == NULL || barrier_cbs_wq == 0)
+ if (barrier_cbs_tasks == NULL || !barrier_cbs_wq)
return -ENOMEM;
for (i = 0; i < n_barrier_cbs; i++) {
init_waitqueue_head(&barrier_cbs_wq[i]);
diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index e441b77b614..5b8ad827fd8 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -105,7 +105,7 @@ int rcu_num_nodes __read_mostly = NUM_RCU_NODES; /* Total # rcu_nodes in use. */
* The rcu_scheduler_active variable transitions from zero to one just
* before the first task is spawned. So when this variable is zero, RCU
* can assume that there is but one task, allowing RCU to (for example)
- * optimized synchronize_sched() to a simple barrier(). When this variable
+ * optimize synchronize_sched() to a simple barrier(). When this variable
* is one, RCU must actually do all the hard work required to detect real
* grace periods. This variable is also used to suppress boot-time false
* positives from lockdep-RCU error checking.
@@ -217,12 +217,6 @@ module_param(blimit, long, 0444);
module_param(qhimark, long, 0444);
module_param(qlowmark, long, 0444);
-int rcu_cpu_stall_suppress __read_mostly; /* 1 = suppress stall warnings. */
-int rcu_cpu_stall_timeout __read_mostly = CONFIG_RCU_CPU_STALL_TIMEOUT;
-
-module_param(rcu_cpu_stall_suppress, int, 0644);
-module_param(rcu_cpu_stall_timeout, int, 0644);
-
static ulong jiffies_till_first_fqs = RCU_JIFFIES_TILL_FORCE_QS;
static ulong jiffies_till_next_fqs = RCU_JIFFIES_TILL_FORCE_QS;
@@ -305,17 +299,27 @@ cpu_has_callbacks_ready_to_invoke(struct rcu_data *rdp)
}
/*
- * Does the current CPU require a yet-as-unscheduled grace period?
+ * Does the current CPU require a not-yet-started grace period?
+ * The caller must have disabled interrupts to prevent races with
+ * normal callback registry.
*/
static int
cpu_needs_another_gp(struct rcu_state *rsp, struct rcu_data *rdp)
{
- struct rcu_head **ntp;
+ int i;
- ntp = rdp->nxttail[RCU_DONE_TAIL +
- (ACCESS_ONCE(rsp->completed) != rdp->completed)];
- return rdp->nxttail[RCU_DONE_TAIL] && ntp && *ntp &&
- !rcu_gp_in_progress(rsp);
+ if (rcu_gp_in_progress(rsp))
+ return 0; /* No, a grace period is already in progress. */
+ if (!rdp->nxttail[RCU_NEXT_TAIL])
+ return 0; /* No, this is a no-CBs (or offline) CPU. */
+ if (*rdp->nxttail[RCU_NEXT_READY_TAIL])
+ return 1; /* Yes, this CPU has newly registered callbacks. */
+ for (i = RCU_WAIT_TAIL; i < RCU_NEXT_TAIL; i++)
+ if (rdp->nxttail[i - 1] != rdp->nxttail[i] &&
+ ULONG_CMP_LT(ACCESS_ONCE(rsp->completed),
+ rdp->nxtcompleted[i]))
+ return 1; /* Yes, CBs for future grace period. */
+ return 0; /* No grace period needed. */
}
/*
@@ -336,7 +340,7 @@ static struct rcu_node *rcu_get_root(struct rcu_state *rsp)
static void rcu_eqs_enter_common(struct rcu_dynticks *rdtp, long long oldval,
bool user)
{
- trace_rcu_dyntick("Start", oldval, 0);
+ trace_rcu_dyntick("Start", oldval, rdtp->dynticks_nesting);
if (!user && !is_idle_task(current)) {
struct task_struct *idle = idle_task(smp_processor_id());
@@ -727,7 +731,7 @@ EXPORT_SYMBOL_GPL(rcu_lockdep_current_cpu_online);
* interrupt from idle, return true. The caller must have at least
* disabled preemption.
*/
-int rcu_is_cpu_rrupt_from_idle(void)
+static int rcu_is_cpu_rrupt_from_idle(void)
{
return __get_cpu_var(rcu_dynticks).dynticks_nesting <= 1;
}
@@ -793,28 +797,10 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp)
return 0;
}
-static int jiffies_till_stall_check(void)
-{
- int till_stall_check = ACCESS_ONCE(rcu_cpu_stall_timeout);
-
- /*
- * Limit check must be consistent with the Kconfig limits
- * for CONFIG_RCU_CPU_STALL_TIMEOUT.
- */
- if (till_stall_check < 3) {
- ACCESS_ONCE(rcu_cpu_stall_timeout) = 3;
- till_stall_check = 3;
- } else if (till_stall_check > 300) {
- ACCESS_ONCE(rcu_cpu_stall_timeout) = 300;
- till_stall_check = 300;
- }
- return till_stall_check * HZ + RCU_STALL_DELAY_DELTA;
-}
-
static void record_gp_stall_check_time(struct rcu_state *rsp)
{
rsp->gp_start = jiffies;
- rsp->jiffies_stall = jiffies + jiffies_till_stall_check();
+ rsp->jiffies_stall = jiffies + rcu_jiffies_till_stall_check();
}
/*
@@ -857,7 +843,7 @@ static void print_other_cpu_stall(struct rcu_state *rsp)
raw_spin_unlock_irqrestore(&rnp->lock, flags);
return;
}
- rsp->jiffies_stall = jiffies + 3 * jiffies_till_stall_check() + 3;
+ rsp->jiffies_stall = jiffies + 3 * rcu_jiffies_till_stall_check() + 3;
raw_spin_unlock_irqrestore(&rnp->lock, flags);
/*
@@ -935,7 +921,7 @@ static void print_cpu_stall(struct rcu_state *rsp)
raw_spin_lock_irqsave(&rnp->lock, flags);
if (ULONG_CMP_GE(jiffies, rsp->jiffies_stall))
rsp->jiffies_stall = jiffies +
- 3 * jiffies_till_stall_check() + 3;
+ 3 * rcu_jiffies_till_stall_check() + 3;
raw_spin_unlock_irqrestore(&rnp->lock, flags);
set_need_resched(); /* kick ourselves to get things going. */
@@ -966,12 +952,6 @@ static void check_cpu_stall(struct rcu_state *rsp, struct rcu_data *rdp)
}
}
-static int rcu_panic(struct notifier_block *this, unsigned long ev, void *ptr)
-{
- rcu_cpu_stall_suppress = 1;
- return NOTIFY_DONE;
-}
-
/**
* rcu_cpu_stall_reset - prevent further stall warnings in current grace period
*
@@ -989,15 +969,6 @@ void rcu_cpu_stall_reset(void)
rsp->jiffies_stall = jiffies + ULONG_MAX / 2;
}
-static struct notifier_block rcu_panic_block = {
- .notifier_call = rcu_panic,
-};
-
-static void __init check_cpu_stall_init(void)
-{
- atomic_notifier_chain_register(&panic_notifier_list, &rcu_panic_block);
-}
-
/*
* Update CPU-local rcu_data state to record the newly noticed grace period.
* This is used both when we started the grace period and when we notice
@@ -1071,6 +1042,145 @@ static void init_callback_list(struct rcu_data *rdp)
}
/*
+ * Determine the value that ->completed will have at the end of the
+ * next subsequent grace period. This is used to tag callbacks so that
+ * a CPU can invoke callbacks in a timely fashion even if that CPU has
+ * been dyntick-idle for an extended period with callbacks under the
+ * influence of RCU_FAST_NO_HZ.
+ *
+ * The caller must hold rnp->lock with interrupts disabled.
+ */
+static unsigned long rcu_cbs_completed(struct rcu_state *rsp,
+ struct rcu_node *rnp)
+{
+ /*
+ * If RCU is idle, we just wait for the next grace period.
+ * But we can only be sure that RCU is idle if we are looking
+ * at the root rcu_node structure -- otherwise, a new grace
+ * period might have started, but just not yet gotten around
+ * to initializing the current non-root rcu_node structure.
+ */
+ if (rcu_get_root(rsp) == rnp && rnp->gpnum == rnp->completed)
+ return rnp->completed + 1;
+
+ /*
+ * Otherwise, wait for a possible partial grace period and
+ * then the subsequent full grace period.
+ */
+ return rnp->completed + 2;
+}
+
+/*
+ * If there is room, assign a ->completed number to any callbacks on
+ * this CPU that have not already been assigned. Also accelerate any
+ * callbacks that were previously assigned a ->completed number that has
+ * since proven to be too conservative, which can happen if callbacks get
+ * assigned a ->completed number while RCU is idle, but with reference to
+ * a non-root rcu_node structure. This function is idempotent, so it does
+ * not hurt to call it repeatedly.
+ *
+ * The caller must hold rnp->lock with interrupts disabled.
+ */
+static void rcu_accelerate_cbs(struct rcu_state *rsp, struct rcu_node *rnp,
+ struct rcu_data *rdp)
+{
+ unsigned long c;
+ int i;
+
+ /* If the CPU has no callbacks, nothing to do. */
+ if (!rdp->nxttail[RCU_NEXT_TAIL] || !*rdp->nxttail[RCU_DONE_TAIL])
+ return;
+
+ /*
+ * Starting from the sublist containing the callbacks most
+ * recently assigned a ->completed number and working down, find the
+ * first sublist that is not assignable to an upcoming grace period.
+ * Such a sublist has something in it (first two tests) and has
+ * a ->completed number assigned that will complete sooner than
+ * the ->completed number for newly arrived callbacks (last test).
+ *
+ * The key point is that any later sublist can be assigned the
+ * same ->completed number as the newly arrived callbacks, which
+ * means that the callbacks in any of these later sublist can be
+ * grouped into a single sublist, whether or not they have already
+ * been assigned a ->completed number.
+ */
+ c = rcu_cbs_completed(rsp, rnp);
+ for (i = RCU_NEXT_TAIL - 1; i > RCU_DONE_TAIL; i--)
+ if (rdp->nxttail[i] != rdp->nxttail[i - 1] &&
+ !ULONG_CMP_GE(rdp->nxtcompleted[i], c))
+ break;
+
+ /*
+ * If there are no sublist for unassigned callbacks, leave.
+ * At the same time, advance "i" one sublist, so that "i" will
+ * index into the sublist where all the remaining callbacks should
+ * be grouped into.
+ */
+ if (++i >= RCU_NEXT_TAIL)
+ return;
+
+ /*
+ * Assign all subsequent callbacks' ->completed number to the next
+ * full grace period and group them all in the sublist initially
+ * indexed by "i".
+ */
+ for (; i <= RCU_NEXT_TAIL; i++) {
+ rdp->nxttail[i] = rdp->nxttail[RCU_NEXT_TAIL];
+ rdp->nxtcompleted[i] = c;
+ }
+
+ /* Trace depending on how much we were able to accelerate. */
+ if (!*rdp->nxttail[RCU_WAIT_TAIL])
+ trace_rcu_grace_period(rsp->name, rdp->gpnum, "AccWaitCB");
+ else
+ trace_rcu_grace_period(rsp->name, rdp->gpnum, "AccReadyCB");
+}
+
+/*
+ * Move any callbacks whose grace period has completed to the
+ * RCU_DONE_TAIL sublist, then compact the remaining sublists and
+ * assign ->completed numbers to any callbacks in the RCU_NEXT_TAIL
+ * sublist. This function is idempotent, so it does not hurt to
+ * invoke it repeatedly. As long as it is not invoked -too- often...
+ *
+ * The caller must hold rnp->lock with interrupts disabled.
+ */
+static void rcu_advance_cbs(struct rcu_state *rsp, struct rcu_node *rnp,
+ struct rcu_data *rdp)
+{
+ int i, j;
+
+ /* If the CPU has no callbacks, nothing to do. */
+ if (!rdp->nxttail[RCU_NEXT_TAIL] || !*rdp->nxttail[RCU_DONE_TAIL])
+ return;
+
+ /*
+ * Find all callbacks whose ->completed numbers indicate that they
+ * are ready to invoke, and put them into the RCU_DONE_TAIL sublist.
+ */
+ for (i = RCU_WAIT_TAIL; i < RCU_NEXT_TAIL; i++) {
+ if (ULONG_CMP_LT(rnp->completed, rdp->nxtcompleted[i]))
+ break;
+ rdp->nxttail[RCU_DONE_TAIL] = rdp->nxttail[i];
+ }
+ /* Clean up any sublist tail pointers that were misordered above. */
+ for (j = RCU_WAIT_TAIL; j < i; j++)
+ rdp->nxttail[j] = rdp->nxttail[RCU_DONE_TAIL];
+
+ /* Copy down callbacks to fill in empty sublists. */
+ for (j = RCU_WAIT_TAIL; i < RCU_NEXT_TAIL; i++, j++) {
+ if (rdp->nxttail[j] == rdp->nxttail[RCU_NEXT_TAIL])
+ break;
+ rdp->nxttail[j] = rdp->nxttail[i];
+ rdp->nxtcompleted[j] = rdp->nxtcompleted[i];
+ }
+
+ /* Classify any remaining callbacks. */
+ rcu_accelerate_cbs(rsp, rnp, rdp);
+}
+
+/*
* Advance this CPU's callbacks, but only if the current grace period
* has ended. This may be called only from the CPU to whom the rdp
* belongs. In addition, the corresponding leaf rcu_node structure's
@@ -1080,12 +1190,15 @@ static void
__rcu_process_gp_end(struct rcu_state *rsp, struct rcu_node *rnp, struct rcu_data *rdp)
{
/* Did another grace period end? */
- if (rdp->completed != rnp->completed) {
+ if (rdp->completed == rnp->completed) {
- /* Advance callbacks. No harm if list empty. */
- rdp->nxttail[RCU_DONE_TAIL] = rdp->nxttail[RCU_WAIT_TAIL];
- rdp->nxttail[RCU_WAIT_TAIL] = rdp->nxttail[RCU_NEXT_READY_TAIL];
- rdp->nxttail[RCU_NEXT_READY_TAIL] = rdp->nxttail[RCU_NEXT_TAIL];
+ /* No, so just accelerate recent callbacks. */
+ rcu_accelerate_cbs(rsp, rnp, rdp);
+
+ } else {
+
+ /* Advance callbacks. */
+ rcu_advance_cbs(rsp, rnp, rdp);
/* Remember that we saw this grace-period completion. */
rdp->completed = rnp->completed;
@@ -1392,17 +1505,10 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
/*
* Because there is no grace period in progress right now,
* any callbacks we have up to this point will be satisfied
- * by the next grace period. So promote all callbacks to be
- * handled after the end of the next grace period. If the
- * CPU is not yet aware of the end of the previous grace period,
- * we need to allow for the callback advancement that will
- * occur when it does become aware. Deadlock prevents us from
- * making it aware at this point: We cannot acquire a leaf
- * rcu_node ->lock while holding the root rcu_node ->lock.
+ * by the next grace period. So this is a good place to
+ * assign a grace period number to recently posted callbacks.
*/
- rdp->nxttail[RCU_NEXT_READY_TAIL] = rdp->nxttail[RCU_NEXT_TAIL];
- if (rdp->completed == rsp->completed)
- rdp->nxttail[RCU_WAIT_TAIL] = rdp->nxttail[RCU_NEXT_TAIL];
+ rcu_accelerate_cbs(rsp, rnp, rdp);
rsp->gp_flags = RCU_GP_FLAG_INIT;
raw_spin_unlock(&rnp->lock); /* Interrupts remain disabled. */
@@ -1527,7 +1633,7 @@ rcu_report_qs_rdp(int cpu, struct rcu_state *rsp, struct rcu_data *rdp)
* This GP can't end until cpu checks in, so all of our
* callbacks can be processed during the next GP.
*/
- rdp->nxttail[RCU_NEXT_READY_TAIL] = rdp->nxttail[RCU_NEXT_TAIL];
+ rcu_accelerate_cbs(rsp, rnp, rdp);
rcu_report_qs_rnp(mask, rsp, rnp, flags); /* rlses rnp->lock */
}
@@ -1779,7 +1885,7 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp)
long bl, count, count_lazy;
int i;
- /* If no callbacks are ready, just return.*/
+ /* If no callbacks are ready, just return. */
if (!cpu_has_callbacks_ready_to_invoke(rdp)) {
trace_rcu_batch_start(rsp->name, rdp->qlen_lazy, rdp->qlen, 0);
trace_rcu_batch_end(rsp->name, 0, !!ACCESS_ONCE(rdp->nxtlist),
@@ -2008,19 +2114,19 @@ __rcu_process_callbacks(struct rcu_state *rsp)
WARN_ON_ONCE(rdp->beenonline == 0);
- /*
- * Advance callbacks in response to end of earlier grace
- * period that some other CPU ended.
- */
+ /* Handle the end of a grace period that some other CPU ended. */
rcu_process_gp_end(rsp, rdp);
/* Update RCU state based on any recent quiescent states. */
rcu_check_quiescent_state(rsp, rdp);
/* Does this CPU require a not-yet-started grace period? */
+ local_irq_save(flags);
if (cpu_needs_another_gp(rsp, rdp)) {
- raw_spin_lock_irqsave(&rcu_get_root(rsp)->lock, flags);
+ raw_spin_lock(&rcu_get_root(rsp)->lock); /* irqs disabled. */
rcu_start_gp(rsp, flags); /* releases above lock */
+ } else {
+ local_irq_restore(flags);
}
/* If there are callbacks ready, invoke them. */
@@ -2719,9 +2825,6 @@ rcu_boot_init_percpu_data(int cpu, struct rcu_state *rsp)
rdp->dynticks = &per_cpu(rcu_dynticks, cpu);
WARN_ON_ONCE(rdp->dynticks->dynticks_nesting != DYNTICK_TASK_EXIT_IDLE);
WARN_ON_ONCE(atomic_read(&rdp->dynticks->dynticks) != 1);
-#ifdef CONFIG_RCU_USER_QS
- WARN_ON_ONCE(rdp->dynticks->in_user);
-#endif
rdp->cpu = cpu;
rdp->rsp = rsp;
rcu_boot_init_nocb_percpu_data(rdp);
@@ -2938,6 +3041,10 @@ static void __init rcu_init_one(struct rcu_state *rsp,
BUILD_BUG_ON(MAX_RCU_LVLS > ARRAY_SIZE(buf)); /* Fix buf[] init! */
+ /* Silence gcc 4.8 warning about array index out of range. */
+ if (rcu_num_lvls > RCU_NUM_LVLS)
+ panic("rcu_init_one: rcu_num_lvls overflow");
+
/* Initialize the level-tracking arrays. */
for (i = 0; i < rcu_num_lvls; i++)
@@ -3074,7 +3181,6 @@ void __init rcu_init(void)
cpu_notifier(rcu_cpu_notify, 0);
for_each_online_cpu(cpu)
rcu_cpu_notify(NULL, CPU_UP_PREPARE, (void *)(long)cpu);
- check_cpu_stall_init();
}
#include "rcutree_plugin.h"
diff --git a/kernel/rcutree.h b/kernel/rcutree.h
index 4b69291b093..c896b5045d9 100644
--- a/kernel/rcutree.h
+++ b/kernel/rcutree.h
@@ -102,10 +102,6 @@ struct rcu_dynticks {
/* idle-period nonlazy_posted snapshot. */
int tick_nohz_enabled_snap; /* Previously seen value from sysfs. */
#endif /* #ifdef CONFIG_RCU_FAST_NO_HZ */
-#ifdef CONFIG_RCU_USER_QS
- bool ignore_user_qs; /* Treat userspace as extended QS or not */
- bool in_user; /* Is the CPU in userland from RCU POV? */
-#endif
};
/* RCU's kthread states for tracing. */
@@ -282,6 +278,8 @@ struct rcu_data {
*/
struct rcu_head *nxtlist;
struct rcu_head **nxttail[RCU_NEXT_SIZE];
+ unsigned long nxtcompleted[RCU_NEXT_SIZE];
+ /* grace periods for sublists. */
long qlen_lazy; /* # of lazy queued callbacks */
long qlen; /* # of queued callbacks, incl lazy */
long qlen_last_fqs_check;
@@ -343,11 +341,6 @@ struct rcu_data {
#define RCU_JIFFIES_TILL_FORCE_QS 3 /* for rsp->jiffies_force_qs */
-#ifdef CONFIG_PROVE_RCU
-#define RCU_STALL_DELAY_DELTA (5 * HZ)
-#else
-#define RCU_STALL_DELAY_DELTA 0
-#endif
#define RCU_STALL_RAT_DELAY 2 /* Allow other CPUs time */
/* to take at least one */
/* scheduling clock irq */
diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h
index f6e5ec2932b..c1cc7e17ff9 100644
--- a/kernel/rcutree_plugin.h
+++ b/kernel/rcutree_plugin.h
@@ -40,8 +40,7 @@
#ifdef CONFIG_RCU_NOCB_CPU
static cpumask_var_t rcu_nocb_mask; /* CPUs to have callbacks offloaded. */
static bool have_rcu_nocb_mask; /* Was rcu_nocb_mask allocated? */
-static bool rcu_nocb_poll; /* Offload kthread are to poll. */
-module_param(rcu_nocb_poll, bool, 0444);
+static bool __read_mostly rcu_nocb_poll; /* Offload kthread are to poll. */
static char __initdata nocb_buf[NR_CPUS * 5];
#endif /* #ifdef CONFIG_RCU_NOCB_CPU */
@@ -2159,6 +2158,13 @@ static int __init rcu_nocb_setup(char *str)
}
__setup("rcu_nocbs=", rcu_nocb_setup);
+static int __init parse_rcu_nocb_poll(char *arg)
+{
+ rcu_nocb_poll = 1;
+ return 0;
+}
+early_param("rcu_nocb_poll", parse_rcu_nocb_poll);
+
/* Is the specified CPU a no-CPUs CPU? */
static bool is_nocb_cpu(int cpu)
{
@@ -2366,10 +2372,11 @@ static int rcu_nocb_kthread(void *arg)
for (;;) {
/* If not polling, wait for next batch of callbacks. */
if (!rcu_nocb_poll)
- wait_event(rdp->nocb_wq, rdp->nocb_head);
+ wait_event_interruptible(rdp->nocb_wq, rdp->nocb_head);
list = ACCESS_ONCE(rdp->nocb_head);
if (!list) {
schedule_timeout_interruptible(1);
+ flush_signals(current);
continue;
}
diff --git a/kernel/rtmutex-debug.c b/kernel/rtmutex-debug.c
index 16502d3a71c..13b243a323f 100644
--- a/kernel/rtmutex-debug.c
+++ b/kernel/rtmutex-debug.c
@@ -17,6 +17,7 @@
* See rt.c in preempt-rt for proper credits and further information
*/
#include <linux/sched.h>
+#include <linux/sched/rt.h>
#include <linux/delay.h>
#include <linux/export.h>
#include <linux/spinlock.h>
diff --git a/kernel/rtmutex-tester.c b/kernel/rtmutex-tester.c
index 98ec4947546..7890b10084a 100644
--- a/kernel/rtmutex-tester.c
+++ b/kernel/rtmutex-tester.c
@@ -10,6 +10,7 @@
#include <linux/kthread.h>
#include <linux/export.h>
#include <linux/sched.h>
+#include <linux/sched/rt.h>
#include <linux/spinlock.h>
#include <linux/timer.h>
#include <linux/freezer.h>
diff --git a/kernel/rtmutex.c b/kernel/rtmutex.c
index a242e691c99..1e09308bf2a 100644
--- a/kernel/rtmutex.c
+++ b/kernel/rtmutex.c
@@ -13,6 +13,7 @@
#include <linux/spinlock.h>
#include <linux/export.h>
#include <linux/sched.h>
+#include <linux/sched/rt.h>
#include <linux/timer.h>
#include "rtmutex_common.h"
diff --git a/kernel/rwsem.c b/kernel/rwsem.c
index 6850f53e02d..b3c6c3fcd84 100644
--- a/kernel/rwsem.c
+++ b/kernel/rwsem.c
@@ -116,6 +116,16 @@ void down_read_nested(struct rw_semaphore *sem, int subclass)
EXPORT_SYMBOL(down_read_nested);
+void _down_write_nest_lock(struct rw_semaphore *sem, struct lockdep_map *nest)
+{
+ might_sleep();
+ rwsem_acquire_nest(&sem->dep_map, 0, 0, nest, _RET_IP_);
+
+ LOCK_CONTENDED(sem, __down_write_trylock, __down_write);
+}
+
+EXPORT_SYMBOL(_down_write_nest_lock);
+
void down_write_nested(struct rw_semaphore *sem, int subclass)
{
might_sleep();
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 106167243d6..3a673a3b0c6 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -83,7 +83,7 @@
#endif
#include "sched.h"
-#include "../workqueue_sched.h"
+#include "../workqueue_internal.h"
#include "../smpboot.h"
#define CREATE_TRACE_POINTS
@@ -1523,7 +1523,8 @@ out:
*/
int wake_up_process(struct task_struct *p)
{
- return try_to_wake_up(p, TASK_ALL, 0);
+ WARN_ON(task_is_stopped_or_traced(p));
+ return try_to_wake_up(p, TASK_NORMAL, 0);
}
EXPORT_SYMBOL(wake_up_process);
@@ -4370,7 +4371,7 @@ bool __sched yield_to(struct task_struct *p, bool preempt)
struct task_struct *curr = current;
struct rq *rq, *p_rq;
unsigned long flags;
- bool yielded = 0;
+ int yielded = 0;
local_irq_save(flags);
rq = this_rq();
@@ -4666,6 +4667,7 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu)
*/
idle->sched_class = &idle_sched_class;
ftrace_graph_init_idle_task(idle, cpu);
+ vtime_init_idle(idle);
#if defined(CONFIG_SMP)
sprintf(idle->comm, "%s/%d", INIT_TASK_COMM, cpu);
#endif
@@ -7514,6 +7516,25 @@ static int sched_rt_global_constraints(void)
}
#endif /* CONFIG_RT_GROUP_SCHED */
+int sched_rr_handler(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp,
+ loff_t *ppos)
+{
+ int ret;
+ static DEFINE_MUTEX(mutex);
+
+ mutex_lock(&mutex);
+ ret = proc_dointvec(table, write, buffer, lenp, ppos);
+ /* make sure that internally we keep jiffies */
+ /* also, writing zero resets timeslice to default */
+ if (!ret && write) {
+ sched_rr_timeslice = sched_rr_timeslice <= 0 ?
+ RR_TIMESLICE : msecs_to_jiffies(sched_rr_timeslice);
+ }
+ mutex_unlock(&mutex);
+ return ret;
+}
+
int sched_rt_handler(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp,
loff_t *ppos)
diff --git a/kernel/sched/cpupri.c b/kernel/sched/cpupri.c
index 23aa789c53e..1095e878a46 100644
--- a/kernel/sched/cpupri.c
+++ b/kernel/sched/cpupri.c
@@ -28,6 +28,8 @@
*/
#include <linux/gfp.h>
+#include <linux/sched.h>
+#include <linux/sched/rt.h>
#include "cpupri.h"
/* Convert between a 140 based task->prio, and our 102 based cpupri */
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index 293b202fcf7..9857329ed28 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -3,6 +3,7 @@
#include <linux/tsacct_kern.h>
#include <linux/kernel_stat.h>
#include <linux/static_key.h>
+#include <linux/context_tracking.h>
#include "sched.h"
@@ -163,7 +164,7 @@ void account_user_time(struct task_struct *p, cputime_t cputime,
task_group_account_field(p, index, (__force u64) cputime);
/* Account for user time used */
- acct_update_integrals(p);
+ acct_account_cputime(p);
}
/*
@@ -213,7 +214,7 @@ void __account_system_time(struct task_struct *p, cputime_t cputime,
task_group_account_field(p, index, (__force u64) cputime);
/* Account for system time used */
- acct_update_integrals(p);
+ acct_account_cputime(p);
}
/*
@@ -295,6 +296,7 @@ static __always_inline bool steal_account_process_tick(void)
void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times)
{
struct signal_struct *sig = tsk->signal;
+ cputime_t utime, stime;
struct task_struct *t;
times->utime = sig->utime;
@@ -308,16 +310,15 @@ void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times)
t = tsk;
do {
- times->utime += t->utime;
- times->stime += t->stime;
+ task_cputime(tsk, &utime, &stime);
+ times->utime += utime;
+ times->stime += stime;
times->sum_exec_runtime += task_sched_runtime(t);
} while_each_thread(tsk, t);
out:
rcu_read_unlock();
}
-#ifndef CONFIG_VIRT_CPU_ACCOUNTING
-
#ifdef CONFIG_IRQ_TIME_ACCOUNTING
/*
* Account a tick to a process and cpustat
@@ -382,11 +383,12 @@ static void irqtime_account_idle_ticks(int ticks)
irqtime_account_process_tick(current, 0, rq);
}
#else /* CONFIG_IRQ_TIME_ACCOUNTING */
-static void irqtime_account_idle_ticks(int ticks) {}
-static void irqtime_account_process_tick(struct task_struct *p, int user_tick,
+static inline void irqtime_account_idle_ticks(int ticks) {}
+static inline void irqtime_account_process_tick(struct task_struct *p, int user_tick,
struct rq *rq) {}
#endif /* CONFIG_IRQ_TIME_ACCOUNTING */
+#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
/*
* Account a single tick of cpu time.
* @p: the process that the cpu time gets accounted to
@@ -397,6 +399,9 @@ void account_process_tick(struct task_struct *p, int user_tick)
cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy);
struct rq *rq = this_rq();
+ if (vtime_accounting_enabled())
+ return;
+
if (sched_clock_irqtime) {
irqtime_account_process_tick(p, user_tick, rq);
return;
@@ -438,8 +443,7 @@ void account_idle_ticks(unsigned long ticks)
account_idle_time(jiffies_to_cputime(ticks));
}
-
-#endif
+#endif /* !CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */
/*
* Use precise platform statistics if available:
@@ -461,25 +465,20 @@ void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime
*st = cputime.stime;
}
-void vtime_account_system_irqsafe(struct task_struct *tsk)
-{
- unsigned long flags;
-
- local_irq_save(flags);
- vtime_account_system(tsk);
- local_irq_restore(flags);
-}
-EXPORT_SYMBOL_GPL(vtime_account_system_irqsafe);
-
#ifndef __ARCH_HAS_VTIME_TASK_SWITCH
void vtime_task_switch(struct task_struct *prev)
{
+ if (!vtime_accounting_enabled())
+ return;
+
if (is_idle_task(prev))
vtime_account_idle(prev);
else
vtime_account_system(prev);
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
vtime_account_user(prev);
+#endif
arch_vtime_task_switch(prev);
}
#endif
@@ -493,27 +492,40 @@ void vtime_task_switch(struct task_struct *prev)
* vtime_account().
*/
#ifndef __ARCH_HAS_VTIME_ACCOUNT
-void vtime_account(struct task_struct *tsk)
+void vtime_account_irq_enter(struct task_struct *tsk)
{
- if (in_interrupt() || !is_idle_task(tsk))
- vtime_account_system(tsk);
- else
- vtime_account_idle(tsk);
+ if (!vtime_accounting_enabled())
+ return;
+
+ if (!in_interrupt()) {
+ /*
+ * If we interrupted user, context_tracking_in_user()
+ * is 1 because the context tracking don't hook
+ * on irq entry/exit. This way we know if
+ * we need to flush user time on kernel entry.
+ */
+ if (context_tracking_in_user()) {
+ vtime_account_user(tsk);
+ return;
+ }
+
+ if (is_idle_task(tsk)) {
+ vtime_account_idle(tsk);
+ return;
+ }
+ }
+ vtime_account_system(tsk);
}
-EXPORT_SYMBOL_GPL(vtime_account);
+EXPORT_SYMBOL_GPL(vtime_account_irq_enter);
#endif /* __ARCH_HAS_VTIME_ACCOUNT */
-#else
-
-#ifndef nsecs_to_cputime
-# define nsecs_to_cputime(__nsecs) nsecs_to_jiffies(__nsecs)
-#endif
+#else /* !CONFIG_VIRT_CPU_ACCOUNTING */
-static cputime_t scale_utime(cputime_t utime, cputime_t rtime, cputime_t total)
+static cputime_t scale_stime(cputime_t stime, cputime_t rtime, cputime_t total)
{
u64 temp = (__force u64) rtime;
- temp *= (__force u64) utime;
+ temp *= (__force u64) stime;
if (sizeof(cputime_t) == 4)
temp = div_u64(temp, (__force u32) total);
@@ -531,10 +543,10 @@ static void cputime_adjust(struct task_cputime *curr,
struct cputime *prev,
cputime_t *ut, cputime_t *st)
{
- cputime_t rtime, utime, total;
+ cputime_t rtime, stime, total;
- utime = curr->utime;
- total = utime + curr->stime;
+ stime = curr->stime;
+ total = stime + curr->utime;
/*
* Tick based cputime accounting depend on random scheduling
@@ -549,17 +561,17 @@ static void cputime_adjust(struct task_cputime *curr,
rtime = nsecs_to_cputime(curr->sum_exec_runtime);
if (total)
- utime = scale_utime(utime, rtime, total);
+ stime = scale_stime(stime, rtime, total);
else
- utime = rtime;
+ stime = rtime;
/*
* If the tick based count grows faster than the scheduler one,
* the result of the scaling may go backward.
* Let's enforce monotonicity.
*/
- prev->utime = max(prev->utime, utime);
- prev->stime = max(prev->stime, rtime - prev->utime);
+ prev->stime = max(prev->stime, stime);
+ prev->utime = max(prev->utime, rtime - prev->stime);
*ut = prev->utime;
*st = prev->stime;
@@ -568,11 +580,10 @@ static void cputime_adjust(struct task_cputime *curr,
void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st)
{
struct task_cputime cputime = {
- .utime = p->utime,
- .stime = p->stime,
.sum_exec_runtime = p->se.sum_exec_runtime,
};
+ task_cputime(p, &cputime.utime, &cputime.stime);
cputime_adjust(&cputime, &p->prev_cputime, ut, st);
}
@@ -586,4 +597,221 @@ void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime
thread_group_cputime(p, &cputime);
cputime_adjust(&cputime, &p->signal->prev_cputime, ut, st);
}
-#endif
+#endif /* !CONFIG_VIRT_CPU_ACCOUNTING */
+
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
+static unsigned long long vtime_delta(struct task_struct *tsk)
+{
+ unsigned long long clock;
+
+ clock = sched_clock();
+ if (clock < tsk->vtime_snap)
+ return 0;
+
+ return clock - tsk->vtime_snap;
+}
+
+static cputime_t get_vtime_delta(struct task_struct *tsk)
+{
+ unsigned long long delta = vtime_delta(tsk);
+
+ WARN_ON_ONCE(tsk->vtime_snap_whence == VTIME_SLEEPING);
+ tsk->vtime_snap += delta;
+
+ /* CHECKME: always safe to convert nsecs to cputime? */
+ return nsecs_to_cputime(delta);
+}
+
+static void __vtime_account_system(struct task_struct *tsk)
+{
+ cputime_t delta_cpu = get_vtime_delta(tsk);
+
+ account_system_time(tsk, irq_count(), delta_cpu, cputime_to_scaled(delta_cpu));
+}
+
+void vtime_account_system(struct task_struct *tsk)
+{
+ if (!vtime_accounting_enabled())
+ return;
+
+ write_seqlock(&tsk->vtime_seqlock);
+ __vtime_account_system(tsk);
+ write_sequnlock(&tsk->vtime_seqlock);
+}
+
+void vtime_account_irq_exit(struct task_struct *tsk)
+{
+ if (!vtime_accounting_enabled())
+ return;
+
+ write_seqlock(&tsk->vtime_seqlock);
+ if (context_tracking_in_user())
+ tsk->vtime_snap_whence = VTIME_USER;
+ __vtime_account_system(tsk);
+ write_sequnlock(&tsk->vtime_seqlock);
+}
+
+void vtime_account_user(struct task_struct *tsk)
+{
+ cputime_t delta_cpu;
+
+ if (!vtime_accounting_enabled())
+ return;
+
+ delta_cpu = get_vtime_delta(tsk);
+
+ write_seqlock(&tsk->vtime_seqlock);
+ tsk->vtime_snap_whence = VTIME_SYS;
+ account_user_time(tsk, delta_cpu, cputime_to_scaled(delta_cpu));
+ write_sequnlock(&tsk->vtime_seqlock);
+}
+
+void vtime_user_enter(struct task_struct *tsk)
+{
+ if (!vtime_accounting_enabled())
+ return;
+
+ write_seqlock(&tsk->vtime_seqlock);
+ tsk->vtime_snap_whence = VTIME_USER;
+ __vtime_account_system(tsk);
+ write_sequnlock(&tsk->vtime_seqlock);
+}
+
+void vtime_guest_enter(struct task_struct *tsk)
+{
+ write_seqlock(&tsk->vtime_seqlock);
+ __vtime_account_system(tsk);
+ current->flags |= PF_VCPU;
+ write_sequnlock(&tsk->vtime_seqlock);
+}
+
+void vtime_guest_exit(struct task_struct *tsk)
+{
+ write_seqlock(&tsk->vtime_seqlock);
+ __vtime_account_system(tsk);
+ current->flags &= ~PF_VCPU;
+ write_sequnlock(&tsk->vtime_seqlock);
+}
+
+void vtime_account_idle(struct task_struct *tsk)
+{
+ cputime_t delta_cpu = get_vtime_delta(tsk);
+
+ account_idle_time(delta_cpu);
+}
+
+bool vtime_accounting_enabled(void)
+{
+ return context_tracking_active();
+}
+
+void arch_vtime_task_switch(struct task_struct *prev)
+{
+ write_seqlock(&prev->vtime_seqlock);
+ prev->vtime_snap_whence = VTIME_SLEEPING;
+ write_sequnlock(&prev->vtime_seqlock);
+
+ write_seqlock(&current->vtime_seqlock);
+ current->vtime_snap_whence = VTIME_SYS;
+ current->vtime_snap = sched_clock();
+ write_sequnlock(&current->vtime_seqlock);
+}
+
+void vtime_init_idle(struct task_struct *t)
+{
+ unsigned long flags;
+
+ write_seqlock_irqsave(&t->vtime_seqlock, flags);
+ t->vtime_snap_whence = VTIME_SYS;
+ t->vtime_snap = sched_clock();
+ write_sequnlock_irqrestore(&t->vtime_seqlock, flags);
+}
+
+cputime_t task_gtime(struct task_struct *t)
+{
+ unsigned int seq;
+ cputime_t gtime;
+
+ do {
+ seq = read_seqbegin(&t->vtime_seqlock);
+
+ gtime = t->gtime;
+ if (t->flags & PF_VCPU)
+ gtime += vtime_delta(t);
+
+ } while (read_seqretry(&t->vtime_seqlock, seq));
+
+ return gtime;
+}
+
+/*
+ * Fetch cputime raw values from fields of task_struct and
+ * add up the pending nohz execution time since the last
+ * cputime snapshot.
+ */
+static void
+fetch_task_cputime(struct task_struct *t,
+ cputime_t *u_dst, cputime_t *s_dst,
+ cputime_t *u_src, cputime_t *s_src,
+ cputime_t *udelta, cputime_t *sdelta)
+{
+ unsigned int seq;
+ unsigned long long delta;
+
+ do {
+ *udelta = 0;
+ *sdelta = 0;
+
+ seq = read_seqbegin(&t->vtime_seqlock);
+
+ if (u_dst)
+ *u_dst = *u_src;
+ if (s_dst)
+ *s_dst = *s_src;
+
+ /* Task is sleeping, nothing to add */
+ if (t->vtime_snap_whence == VTIME_SLEEPING ||
+ is_idle_task(t))
+ continue;
+
+ delta = vtime_delta(t);
+
+ /*
+ * Task runs either in user or kernel space, add pending nohz time to
+ * the right place.
+ */
+ if (t->vtime_snap_whence == VTIME_USER || t->flags & PF_VCPU) {
+ *udelta = delta;
+ } else {
+ if (t->vtime_snap_whence == VTIME_SYS)
+ *sdelta = delta;
+ }
+ } while (read_seqretry(&t->vtime_seqlock, seq));
+}
+
+
+void task_cputime(struct task_struct *t, cputime_t *utime, cputime_t *stime)
+{
+ cputime_t udelta, sdelta;
+
+ fetch_task_cputime(t, utime, stime, &t->utime,
+ &t->stime, &udelta, &sdelta);
+ if (utime)
+ *utime += udelta;
+ if (stime)
+ *stime += sdelta;
+}
+
+void task_cputime_scaled(struct task_struct *t,
+ cputime_t *utimescaled, cputime_t *stimescaled)
+{
+ cputime_t udelta, sdelta;
+
+ fetch_task_cputime(t, utimescaled, stimescaled,
+ &t->utimescaled, &t->stimescaled, &udelta, &sdelta);
+ if (utimescaled)
+ *utimescaled += cputime_to_scaled(udelta);
+ if (stimescaled)
+ *stimescaled += cputime_to_scaled(sdelta);
+}
+#endif /* CONFIG_VIRT_CPU_ACCOUNTING_GEN */
diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index 38df0db9660..557e7b53b32 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -215,8 +215,8 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
cfs_rq->runnable_load_avg);
SEQ_printf(m, " .%-30s: %lld\n", "blocked_load_avg",
cfs_rq->blocked_load_avg);
- SEQ_printf(m, " .%-30s: %ld\n", "tg_load_avg",
- atomic64_read(&cfs_rq->tg->load_avg));
+ SEQ_printf(m, " .%-30s: %lld\n", "tg_load_avg",
+ (unsigned long long)atomic64_read(&cfs_rq->tg->load_avg));
SEQ_printf(m, " .%-30s: %lld\n", "tg_load_contrib",
cfs_rq->tg_load_contrib);
SEQ_printf(m, " .%-30s: %d\n", "tg_runnable_contrib",
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 5eea8707234..7a33e5986fc 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -1680,9 +1680,7 @@ place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
}
/* ensure we never gain time by being placed backwards. */
- vruntime = max_vruntime(se->vruntime, vruntime);
-
- se->vruntime = vruntime;
+ se->vruntime = max_vruntime(se->vruntime, vruntime);
}
static void check_enqueue_throttle(struct cfs_rq *cfs_rq);
@@ -2663,7 +2661,7 @@ static void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
hrtimer_cancel(&cfs_b->slack_timer);
}
-static void unthrottle_offline_cfs_rqs(struct rq *rq)
+static void __maybe_unused unthrottle_offline_cfs_rqs(struct rq *rq)
{
struct cfs_rq *cfs_rq;
@@ -3254,25 +3252,18 @@ find_idlest_cpu(struct sched_group *group, struct task_struct *p, int this_cpu)
*/
static int select_idle_sibling(struct task_struct *p, int target)
{
- int cpu = smp_processor_id();
- int prev_cpu = task_cpu(p);
struct sched_domain *sd;
struct sched_group *sg;
- int i;
+ int i = task_cpu(p);
- /*
- * If the task is going to be woken-up on this cpu and if it is
- * already idle, then it is the right target.
- */
- if (target == cpu && idle_cpu(cpu))
- return cpu;
+ if (idle_cpu(target))
+ return target;
/*
- * If the task is going to be woken-up on the cpu where it previously
- * ran and if it is currently idle, then it the right target.
+ * If the prevous cpu is cache affine and idle, don't be stupid.
*/
- if (target == prev_cpu && idle_cpu(prev_cpu))
- return prev_cpu;
+ if (i != target && cpus_share_cache(i, target) && idle_cpu(i))
+ return i;
/*
* Otherwise, iterate the domains and find an elegible idle cpu.
@@ -3286,7 +3277,7 @@ static int select_idle_sibling(struct task_struct *p, int target)
goto next;
for_each_cpu(i, sched_group_cpus(sg)) {
- if (!idle_cpu(i))
+ if (i == target || !idle_cpu(i))
goto next;
}
@@ -6101,7 +6092,7 @@ static unsigned int get_rr_interval_fair(struct rq *rq, struct task_struct *task
* idle runqueue:
*/
if (rq->cfs.load.weight)
- rr_interval = NS_TO_JIFFIES(sched_slice(&rq->cfs, se));
+ rr_interval = NS_TO_JIFFIES(sched_slice(cfs_rq_of(se), se));
return rr_interval;
}
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index 418feb01344..127a2c4cf4a 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -7,6 +7,8 @@
#include <linux/slab.h>
+int sched_rr_timeslice = RR_TIMESLICE;
+
static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun);
struct rt_bandwidth def_rt_bandwidth;
@@ -566,7 +568,7 @@ static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq)
static int do_balance_runtime(struct rt_rq *rt_rq)
{
struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
- struct root_domain *rd = cpu_rq(smp_processor_id())->rd;
+ struct root_domain *rd = rq_of_rt_rq(rt_rq)->rd;
int i, weight, more = 0;
u64 rt_period;
@@ -925,8 +927,8 @@ static void update_curr_rt(struct rq *rq)
return;
delta_exec = rq->clock_task - curr->se.exec_start;
- if (unlikely((s64)delta_exec < 0))
- delta_exec = 0;
+ if (unlikely((s64)delta_exec <= 0))
+ return;
schedstat_set(curr->se.statistics.exec_max,
max(curr->se.statistics.exec_max, delta_exec));
@@ -1427,8 +1429,7 @@ static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
static int pick_rt_task(struct rq *rq, struct task_struct *p, int cpu)
{
if (!task_running(rq, p) &&
- (cpu < 0 || cpumask_test_cpu(cpu, tsk_cpus_allowed(p))) &&
- (p->nr_cpus_allowed > 1))
+ cpumask_test_cpu(cpu, tsk_cpus_allowed(p)))
return 1;
return 0;
}
@@ -1889,8 +1890,11 @@ static void switched_from_rt(struct rq *rq, struct task_struct *p)
* we may need to handle the pulling of RT tasks
* now.
*/
- if (p->on_rq && !rq->rt.rt_nr_running)
- pull_rt_task(rq);
+ if (!p->on_rq || rq->rt.rt_nr_running)
+ return;
+
+ if (pull_rt_task(rq))
+ resched_task(rq->curr);
}
void init_sched_rt_class(void)
@@ -1985,7 +1989,11 @@ static void watchdog(struct rq *rq, struct task_struct *p)
if (soft != RLIM_INFINITY) {
unsigned long next;
- p->rt.timeout++;
+ if (p->rt.watchdog_stamp != jiffies) {
+ p->rt.timeout++;
+ p->rt.watchdog_stamp = jiffies;
+ }
+
next = DIV_ROUND_UP(min(soft, hard), USEC_PER_SEC/HZ);
if (p->rt.timeout > next)
p->cputime_expires.sched_exp = p->se.sum_exec_runtime;
@@ -2010,7 +2018,7 @@ static void task_tick_rt(struct rq *rq, struct task_struct *p, int queued)
if (--p->rt.time_slice)
return;
- p->rt.time_slice = RR_TIMESLICE;
+ p->rt.time_slice = sched_rr_timeslice;
/*
* Requeue to the end of queue if we (and all of our ancestors) are the
@@ -2041,7 +2049,7 @@ static unsigned int get_rr_interval_rt(struct rq *rq, struct task_struct *task)
* Time slice is 0 for SCHED_FIFO tasks
*/
if (task->policy == SCHED_RR)
- return RR_TIMESLICE;
+ return sched_rr_timeslice;
else
return 0;
}
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index fc886441436..cc03cfdf469 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -1,5 +1,7 @@
#include <linux/sched.h>
+#include <linux/sched/sysctl.h>
+#include <linux/sched/rt.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/stop_machine.h>
diff --git a/kernel/signal.c b/kernel/signal.c
index 7aaa51d8e5b..7f82adbad48 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -680,23 +680,17 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
* No need to set need_resched since signal event passing
* goes through ->blocked
*/
-void signal_wake_up(struct task_struct *t, int resume)
+void signal_wake_up_state(struct task_struct *t, unsigned int state)
{
- unsigned int mask;
-
set_tsk_thread_flag(t, TIF_SIGPENDING);
-
/*
- * For SIGKILL, we want to wake it up in the stopped/traced/killable
+ * TASK_WAKEKILL also means wake it up in the stopped/traced/killable
* case. We don't check t->state here because there is a race with it
* executing another processor and just now entering stopped state.
* By using wake_up_state, we ensure the process will wake up and
* handle its death signal.
*/
- mask = TASK_INTERRUPTIBLE;
- if (resume)
- mask |= TASK_WAKEKILL;
- if (!wake_up_state(t, mask))
+ if (!wake_up_state(t, state | TASK_INTERRUPTIBLE))
kick_process(t);
}
@@ -844,7 +838,7 @@ static void ptrace_trap_notify(struct task_struct *t)
assert_spin_locked(&t->sighand->siglock);
task_set_jobctl_pending(t, JOBCTL_TRAP_NOTIFY);
- signal_wake_up(t, t->jobctl & JOBCTL_LISTENING);
+ ptrace_signal_wake_up(t, t->jobctl & JOBCTL_LISTENING);
}
/*
@@ -1638,6 +1632,7 @@ bool do_notify_parent(struct task_struct *tsk, int sig)
unsigned long flags;
struct sighand_struct *psig;
bool autoreap = false;
+ cputime_t utime, stime;
BUG_ON(sig == -1);
@@ -1675,8 +1670,9 @@ bool do_notify_parent(struct task_struct *tsk, int sig)
task_uid(tsk));
rcu_read_unlock();
- info.si_utime = cputime_to_clock_t(tsk->utime + tsk->signal->utime);
- info.si_stime = cputime_to_clock_t(tsk->stime + tsk->signal->stime);
+ task_cputime(tsk, &utime, &stime);
+ info.si_utime = cputime_to_clock_t(utime + tsk->signal->utime);
+ info.si_stime = cputime_to_clock_t(stime + tsk->signal->stime);
info.si_status = tsk->exit_code & 0x7f;
if (tsk->exit_code & 0x80)
@@ -1740,6 +1736,7 @@ static void do_notify_parent_cldstop(struct task_struct *tsk,
unsigned long flags;
struct task_struct *parent;
struct sighand_struct *sighand;
+ cputime_t utime, stime;
if (for_ptracer) {
parent = tsk->parent;
@@ -1758,8 +1755,9 @@ static void do_notify_parent_cldstop(struct task_struct *tsk,
info.si_uid = from_kuid_munged(task_cred_xxx(parent, user_ns), task_uid(tsk));
rcu_read_unlock();
- info.si_utime = cputime_to_clock_t(tsk->utime);
- info.si_stime = cputime_to_clock_t(tsk->stime);
+ task_cputime(tsk, &utime, &stime);
+ info.si_utime = cputime_to_clock_t(utime);
+ info.si_stime = cputime_to_clock_t(stime);
info.si_code = why;
switch (why) {
@@ -1800,6 +1798,10 @@ static inline int may_ptrace_stop(void)
* If SIGKILL was already sent before the caller unlocked
* ->siglock we must see ->core_state != NULL. Otherwise it
* is safe to enter schedule().
+ *
+ * This is almost outdated, a task with the pending SIGKILL can't
+ * block in TASK_TRACED. But PTRACE_EVENT_EXIT can be reported
+ * after SIGKILL was already dequeued.
*/
if (unlikely(current->mm->core_state) &&
unlikely(current->mm == current->parent->mm))
@@ -1925,6 +1927,7 @@ static void ptrace_stop(int exit_code, int why, int clear_code, siginfo_t *info)
if (gstop_done)
do_notify_parent_cldstop(current, false, why);
+ /* tasklist protects us from ptrace_freeze_traced() */
__set_current_state(TASK_RUNNING);
if (clear_code)
current->exit_code = 0;
@@ -2528,11 +2531,8 @@ static void __set_task_blocked(struct task_struct *tsk, const sigset_t *newset)
*/
void set_current_blocked(sigset_t *newset)
{
- struct task_struct *tsk = current;
sigdelsetmask(newset, sigmask(SIGKILL) | sigmask(SIGSTOP));
- spin_lock_irq(&tsk->sighand->siglock);
- __set_task_blocked(tsk, newset);
- spin_unlock_irq(&tsk->sighand->siglock);
+ __set_current_blocked(newset);
}
void __set_current_blocked(const sigset_t *newset)
@@ -3119,8 +3119,9 @@ int __save_altstack(stack_t __user *uss, unsigned long sp)
#ifdef CONFIG_COMPAT
#ifdef CONFIG_GENERIC_SIGALTSTACK
-asmlinkage long compat_sys_sigaltstack(const compat_stack_t __user *uss_ptr,
- compat_stack_t __user *uoss_ptr)
+COMPAT_SYSCALL_DEFINE2(sigaltstack,
+ const compat_stack_t __user *, uss_ptr,
+ compat_stack_t __user *, uoss_ptr)
{
stack_t uss, uoss;
int ret;
@@ -3204,7 +3205,6 @@ SYSCALL_DEFINE3(sigprocmask, int, how, old_sigset_t __user *, nset,
if (nset) {
if (copy_from_user(&new_set, nset, sizeof(*nset)))
return -EFAULT;
- new_set &= ~(sigmask(SIGKILL) | sigmask(SIGSTOP));
new_blocked = current->blocked;
@@ -3222,7 +3222,7 @@ SYSCALL_DEFINE3(sigprocmask, int, how, old_sigset_t __user *, nset,
return -EINVAL;
}
- __set_current_blocked(&new_blocked);
+ set_current_blocked(&new_blocked);
}
if (oset) {
@@ -3286,6 +3286,7 @@ SYSCALL_DEFINE1(ssetmask, int, newmask)
int old = current->blocked.sig[0];
sigset_t newset;
+ siginitset(&newset, newmask);
set_current_blocked(&newset);
return old;
diff --git a/kernel/smp.c b/kernel/smp.c
index 29dd40a9f2f..69f38bd98b4 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -33,6 +33,7 @@ struct call_function_data {
struct call_single_data csd;
atomic_t refs;
cpumask_var_t cpumask;
+ cpumask_var_t cpumask_ipi;
};
static DEFINE_PER_CPU_SHARED_ALIGNED(struct call_function_data, cfd_data);
@@ -56,6 +57,9 @@ hotplug_cfd(struct notifier_block *nfb, unsigned long action, void *hcpu)
if (!zalloc_cpumask_var_node(&cfd->cpumask, GFP_KERNEL,
cpu_to_node(cpu)))
return notifier_from_errno(-ENOMEM);
+ if (!zalloc_cpumask_var_node(&cfd->cpumask_ipi, GFP_KERNEL,
+ cpu_to_node(cpu)))
+ return notifier_from_errno(-ENOMEM);
break;
#ifdef CONFIG_HOTPLUG_CPU
@@ -65,6 +69,7 @@ hotplug_cfd(struct notifier_block *nfb, unsigned long action, void *hcpu)
case CPU_DEAD:
case CPU_DEAD_FROZEN:
free_cpumask_var(cfd->cpumask);
+ free_cpumask_var(cfd->cpumask_ipi);
break;
#endif
};
@@ -526,6 +531,12 @@ void smp_call_function_many(const struct cpumask *mask,
return;
}
+ /*
+ * After we put an entry into the list, data->cpumask
+ * may be cleared again when another CPU sends another IPI for
+ * a SMP function call, so data->cpumask will be zero.
+ */
+ cpumask_copy(data->cpumask_ipi, data->cpumask);
raw_spin_lock_irqsave(&call_function.lock, flags);
/*
* Place entry at the _HEAD_ of the list, so that any cpu still
@@ -549,7 +560,7 @@ void smp_call_function_many(const struct cpumask *mask,
smp_mb();
/* Send a message to all CPUs in the map */
- arch_send_call_function_ipi_mask(data->cpumask);
+ arch_send_call_function_ipi_mask(data->cpumask_ipi);
/* Optionally wait for the CPUs to complete */
if (wait)
diff --git a/kernel/smpboot.c b/kernel/smpboot.c
index d6c5fc05424..d4abac26177 100644
--- a/kernel/smpboot.c
+++ b/kernel/smpboot.c
@@ -183,9 +183,10 @@ __smpboot_create_thread(struct smp_hotplug_thread *ht, unsigned int cpu)
kfree(td);
return PTR_ERR(tsk);
}
-
get_task_struct(tsk);
*per_cpu_ptr(ht->store, cpu) = tsk;
+ if (ht->create)
+ ht->create(cpu);
return 0;
}
@@ -225,7 +226,7 @@ static void smpboot_park_thread(struct smp_hotplug_thread *ht, unsigned int cpu)
{
struct task_struct *tsk = *per_cpu_ptr(ht->store, cpu);
- if (tsk)
+ if (tsk && !ht->selfparking)
kthread_park(tsk);
}
diff --git a/kernel/softirq.c b/kernel/softirq.c
index ed567babe78..f5cc25f147a 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -221,7 +221,7 @@ asmlinkage void __do_softirq(void)
current->flags &= ~PF_MEMALLOC;
pending = local_softirq_pending();
- vtime_account_irq_enter(current);
+ account_irq_enter_time(current);
__local_bh_disable((unsigned long)__builtin_return_address(0),
SOFTIRQ_OFFSET);
@@ -272,7 +272,7 @@ restart:
lockdep_softirq_exit();
- vtime_account_irq_exit(current);
+ account_irq_exit_time(current);
__local_bh_enable(SOFTIRQ_OFFSET);
tsk_restore_flags(current, old_flags, PF_MEMALLOC);
}
@@ -341,7 +341,7 @@ static inline void invoke_softirq(void)
*/
void irq_exit(void)
{
- vtime_account_irq_exit(current);
+ account_irq_exit_time(current);
trace_hardirq_exit();
sub_preempt_count(IRQ_EXIT_OFFSET);
if (!in_interrupt() && local_softirq_pending())
diff --git a/kernel/srcu.c b/kernel/srcu.c
index 2b859828cdc..01d5ccb8bfe 100644
--- a/kernel/srcu.c
+++ b/kernel/srcu.c
@@ -282,12 +282,8 @@ static int srcu_readers_active(struct srcu_struct *sp)
*/
void cleanup_srcu_struct(struct srcu_struct *sp)
{
- int sum;
-
- sum = srcu_readers_active(sp);
- WARN_ON(sum); /* Leakage unless caller handles error. */
- if (sum != 0)
- return;
+ if (WARN_ON(srcu_readers_active(sp)))
+ return; /* Leakage unless caller handles error. */
free_percpu(sp->per_cpu_ref);
sp->per_cpu_ref = NULL;
}
@@ -302,9 +298,8 @@ int __srcu_read_lock(struct srcu_struct *sp)
{
int idx;
+ idx = ACCESS_ONCE(sp->completed) & 0x1;
preempt_disable();
- idx = rcu_dereference_index_check(sp->completed,
- rcu_read_lock_sched_held()) & 0x1;
ACCESS_ONCE(this_cpu_ptr(sp->per_cpu_ref)->c[idx]) += 1;
smp_mb(); /* B */ /* Avoid leaking the critical section. */
ACCESS_ONCE(this_cpu_ptr(sp->per_cpu_ref)->seq[idx]) += 1;
@@ -321,10 +316,8 @@ EXPORT_SYMBOL_GPL(__srcu_read_lock);
*/
void __srcu_read_unlock(struct srcu_struct *sp, int idx)
{
- preempt_disable();
smp_mb(); /* C */ /* Avoid leaking the critical section. */
- ACCESS_ONCE(this_cpu_ptr(sp->per_cpu_ref)->c[idx]) -= 1;
- preempt_enable();
+ this_cpu_dec(sp->per_cpu_ref->c[idx]);
}
EXPORT_SYMBOL_GPL(__srcu_read_unlock);
@@ -423,6 +416,7 @@ static void __synchronize_srcu(struct srcu_struct *sp, int trycount)
!lock_is_held(&rcu_sched_lock_map),
"Illegal synchronize_srcu() in same-type SRCU (or RCU) read-side critical section");
+ might_sleep();
init_completion(&rcu.completion);
head->next = NULL;
@@ -455,10 +449,12 @@ static void __synchronize_srcu(struct srcu_struct *sp, int trycount)
* synchronize_srcu - wait for prior SRCU read-side critical-section completion
* @sp: srcu_struct with which to synchronize.
*
- * Flip the completed counter, and wait for the old count to drain to zero.
- * As with classic RCU, the updater must use some separate means of
- * synchronizing concurrent updates. Can block; must be called from
- * process context.
+ * Wait for the count to drain to zero of both indexes. To avoid the
+ * possible starvation of synchronize_srcu(), it waits for the count of
+ * the index=((->completed & 1) ^ 1) to drain to zero at first,
+ * and then flip the completed and wait for the count of the other index.
+ *
+ * Can block; must be called from process context.
*
* Note that it is illegal to call synchronize_srcu() from the corresponding
* SRCU read-side critical section; doing so will result in deadlock.
@@ -480,12 +476,11 @@ EXPORT_SYMBOL_GPL(synchronize_srcu);
* Wait for an SRCU grace period to elapse, but be more aggressive about
* spinning rather than blocking when waiting.
*
- * Note that it is illegal to call this function while holding any lock
- * that is acquired by a CPU-hotplug notifier. It is also illegal to call
- * synchronize_srcu_expedited() from the corresponding SRCU read-side
- * critical section; doing so will result in deadlock. However, it is
- * perfectly legal to call synchronize_srcu_expedited() on one srcu_struct
- * from some other srcu_struct's read-side critical section, as long as
+ * Note that it is also illegal to call synchronize_srcu_expedited()
+ * from the corresponding SRCU read-side critical section;
+ * doing so will result in deadlock. However, it is perfectly legal
+ * to call synchronize_srcu_expedited() on one srcu_struct from some
+ * other srcu_struct's read-side critical section, as long as
* the resulting graph of srcu_structs is acyclic.
*/
void synchronize_srcu_expedited(struct srcu_struct *sp)
diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
index 2f194e96571..95d178c62d5 100644
--- a/kernel/stop_machine.c
+++ b/kernel/stop_machine.c
@@ -18,7 +18,7 @@
#include <linux/stop_machine.h>
#include <linux/interrupt.h>
#include <linux/kallsyms.h>
-
+#include <linux/smpboot.h>
#include <linux/atomic.h>
/*
@@ -37,10 +37,10 @@ struct cpu_stopper {
spinlock_t lock;
bool enabled; /* is this stopper enabled? */
struct list_head works; /* list of pending works */
- struct task_struct *thread; /* stopper thread */
};
static DEFINE_PER_CPU(struct cpu_stopper, cpu_stopper);
+static DEFINE_PER_CPU(struct task_struct *, cpu_stopper_task);
static bool stop_machine_initialized = false;
static void cpu_stop_init_done(struct cpu_stop_done *done, unsigned int nr_todo)
@@ -62,16 +62,18 @@ static void cpu_stop_signal_done(struct cpu_stop_done *done, bool executed)
}
/* queue @work to @stopper. if offline, @work is completed immediately */
-static void cpu_stop_queue_work(struct cpu_stopper *stopper,
- struct cpu_stop_work *work)
+static void cpu_stop_queue_work(unsigned int cpu, struct cpu_stop_work *work)
{
+ struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu);
+ struct task_struct *p = per_cpu(cpu_stopper_task, cpu);
+
unsigned long flags;
spin_lock_irqsave(&stopper->lock, flags);
if (stopper->enabled) {
list_add_tail(&work->list, &stopper->works);
- wake_up_process(stopper->thread);
+ wake_up_process(p);
} else
cpu_stop_signal_done(work->done, false);
@@ -108,7 +110,7 @@ int stop_one_cpu(unsigned int cpu, cpu_stop_fn_t fn, void *arg)
struct cpu_stop_work work = { .fn = fn, .arg = arg, .done = &done };
cpu_stop_init_done(&done, 1);
- cpu_stop_queue_work(&per_cpu(cpu_stopper, cpu), &work);
+ cpu_stop_queue_work(cpu, &work);
wait_for_completion(&done.completion);
return done.executed ? done.ret : -ENOENT;
}
@@ -130,7 +132,7 @@ void stop_one_cpu_nowait(unsigned int cpu, cpu_stop_fn_t fn, void *arg,
struct cpu_stop_work *work_buf)
{
*work_buf = (struct cpu_stop_work){ .fn = fn, .arg = arg, };
- cpu_stop_queue_work(&per_cpu(cpu_stopper, cpu), work_buf);
+ cpu_stop_queue_work(cpu, work_buf);
}
/* static data for stop_cpus */
@@ -159,8 +161,7 @@ static void queue_stop_cpus_work(const struct cpumask *cpumask,
*/
preempt_disable();
for_each_cpu(cpu, cpumask)
- cpu_stop_queue_work(&per_cpu(cpu_stopper, cpu),
- &per_cpu(stop_cpus_work, cpu));
+ cpu_stop_queue_work(cpu, &per_cpu(stop_cpus_work, cpu));
preempt_enable();
}
@@ -244,20 +245,25 @@ int try_stop_cpus(const struct cpumask *cpumask, cpu_stop_fn_t fn, void *arg)
return ret;
}
-static int cpu_stopper_thread(void *data)
+static int cpu_stop_should_run(unsigned int cpu)
+{
+ struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu);
+ unsigned long flags;
+ int run;
+
+ spin_lock_irqsave(&stopper->lock, flags);
+ run = !list_empty(&stopper->works);
+ spin_unlock_irqrestore(&stopper->lock, flags);
+ return run;
+}
+
+static void cpu_stopper_thread(unsigned int cpu)
{
- struct cpu_stopper *stopper = data;
+ struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu);
struct cpu_stop_work *work;
int ret;
repeat:
- set_current_state(TASK_INTERRUPTIBLE); /* mb paired w/ kthread_stop */
-
- if (kthread_should_stop()) {
- __set_current_state(TASK_RUNNING);
- return 0;
- }
-
work = NULL;
spin_lock_irq(&stopper->lock);
if (!list_empty(&stopper->works)) {
@@ -273,8 +279,6 @@ repeat:
struct cpu_stop_done *done = work->done;
char ksym_buf[KSYM_NAME_LEN] __maybe_unused;
- __set_current_state(TASK_RUNNING);
-
/* cpu stop callbacks are not allowed to sleep */
preempt_disable();
@@ -290,88 +294,55 @@ repeat:
ksym_buf), arg);
cpu_stop_signal_done(done, true);
- } else
- schedule();
-
- goto repeat;
+ goto repeat;
+ }
}
extern void sched_set_stop_task(int cpu, struct task_struct *stop);
-/* manage stopper for a cpu, mostly lifted from sched migration thread mgmt */
-static int __cpuinit cpu_stop_cpu_callback(struct notifier_block *nfb,
- unsigned long action, void *hcpu)
+static void cpu_stop_create(unsigned int cpu)
+{
+ sched_set_stop_task(cpu, per_cpu(cpu_stopper_task, cpu));
+}
+
+static void cpu_stop_park(unsigned int cpu)
{
- unsigned int cpu = (unsigned long)hcpu;
struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu);
- struct task_struct *p;
-
- switch (action & ~CPU_TASKS_FROZEN) {
- case CPU_UP_PREPARE:
- BUG_ON(stopper->thread || stopper->enabled ||
- !list_empty(&stopper->works));
- p = kthread_create_on_node(cpu_stopper_thread,
- stopper,
- cpu_to_node(cpu),
- "migration/%d", cpu);
- if (IS_ERR(p))
- return notifier_from_errno(PTR_ERR(p));
- get_task_struct(p);
- kthread_bind(p, cpu);
- sched_set_stop_task(cpu, p);
- stopper->thread = p;
- break;
-
- case CPU_ONLINE:
- /* strictly unnecessary, as first user will wake it */
- wake_up_process(stopper->thread);
- /* mark enabled */
- spin_lock_irq(&stopper->lock);
- stopper->enabled = true;
- spin_unlock_irq(&stopper->lock);
- break;
-
-#ifdef CONFIG_HOTPLUG_CPU
- case CPU_UP_CANCELED:
- case CPU_POST_DEAD:
- {
- struct cpu_stop_work *work;
-
- sched_set_stop_task(cpu, NULL);
- /* kill the stopper */
- kthread_stop(stopper->thread);
- /* drain remaining works */
- spin_lock_irq(&stopper->lock);
- list_for_each_entry(work, &stopper->works, list)
- cpu_stop_signal_done(work->done, false);
- stopper->enabled = false;
- spin_unlock_irq(&stopper->lock);
- /* release the stopper */
- put_task_struct(stopper->thread);
- stopper->thread = NULL;
- break;
- }
-#endif
- }
+ struct cpu_stop_work *work;
+ unsigned long flags;
- return NOTIFY_OK;
+ /* drain remaining works */
+ spin_lock_irqsave(&stopper->lock, flags);
+ list_for_each_entry(work, &stopper->works, list)
+ cpu_stop_signal_done(work->done, false);
+ stopper->enabled = false;
+ spin_unlock_irqrestore(&stopper->lock, flags);
}
-/*
- * Give it a higher priority so that cpu stopper is available to other
- * cpu notifiers. It currently shares the same priority as sched
- * migration_notifier.
- */
-static struct notifier_block __cpuinitdata cpu_stop_cpu_notifier = {
- .notifier_call = cpu_stop_cpu_callback,
- .priority = 10,
+static void cpu_stop_unpark(unsigned int cpu)
+{
+ struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu);
+
+ spin_lock_irq(&stopper->lock);
+ stopper->enabled = true;
+ spin_unlock_irq(&stopper->lock);
+}
+
+static struct smp_hotplug_thread cpu_stop_threads = {
+ .store = &cpu_stopper_task,
+ .thread_should_run = cpu_stop_should_run,
+ .thread_fn = cpu_stopper_thread,
+ .thread_comm = "migration/%u",
+ .create = cpu_stop_create,
+ .setup = cpu_stop_unpark,
+ .park = cpu_stop_park,
+ .unpark = cpu_stop_unpark,
+ .selfparking = true,
};
static int __init cpu_stop_init(void)
{
- void *bcpu = (void *)(long)smp_processor_id();
unsigned int cpu;
- int err;
for_each_possible_cpu(cpu) {
struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu);
@@ -380,15 +351,8 @@ static int __init cpu_stop_init(void)
INIT_LIST_HEAD(&stopper->works);
}
- /* start one for the boot cpu */
- err = cpu_stop_cpu_callback(&cpu_stop_cpu_notifier, CPU_UP_PREPARE,
- bcpu);
- BUG_ON(err != NOTIFY_OK);
- cpu_stop_cpu_callback(&cpu_stop_cpu_notifier, CPU_ONLINE, bcpu);
- register_cpu_notifier(&cpu_stop_cpu_notifier);
-
+ BUG_ON(smpboot_register_percpu_thread(&cpu_stop_threads));
stop_machine_initialized = true;
-
return 0;
}
early_initcall(cpu_stop_init);
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index c88878db491..4fc9be955c7 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -61,6 +61,7 @@
#include <linux/kmod.h>
#include <linux/capability.h>
#include <linux/binfmts.h>
+#include <linux/sched/sysctl.h>
#include <asm/uaccess.h>
#include <asm/processor.h>
@@ -403,6 +404,13 @@ static struct ctl_table kern_table[] = {
.mode = 0644,
.proc_handler = sched_rt_handler,
},
+ {
+ .procname = "sched_rr_timeslice_ms",
+ .data = &sched_rr_timeslice,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = sched_rr_handler,
+ },
#ifdef CONFIG_SCHED_AUTOGROUP
{
.procname = "sched_autogroup_enabled",
diff --git a/kernel/time.c b/kernel/time.c
index d226c6a3fd2..c2a27dd9314 100644
--- a/kernel/time.c
+++ b/kernel/time.c
@@ -115,6 +115,12 @@ SYSCALL_DEFINE2(gettimeofday, struct timeval __user *, tv,
}
/*
+ * Indicates if there is an offset between the system clock and the hardware
+ * clock/persistent clock/rtc.
+ */
+int persistent_clock_is_local;
+
+/*
* Adjust the time obtained from the CMOS to be UTC time instead of
* local time.
*
@@ -135,6 +141,8 @@ static inline void warp_clock(void)
struct timespec adjust;
adjust = current_kernel_time();
+ if (sys_tz.tz_minuteswest != 0)
+ persistent_clock_is_local = 1;
adjust.tv_sec += sys_tz.tz_minuteswest * 60;
do_settimeofday(&adjust);
}
diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig
index 8601f0db126..24510d84efd 100644
--- a/kernel/time/Kconfig
+++ b/kernel/time/Kconfig
@@ -12,6 +12,11 @@ config CLOCKSOURCE_WATCHDOG
config ARCH_CLOCKSOURCE_DATA
bool
+# Platforms has a persistent clock
+config ALWAYS_USE_PERSISTENT_CLOCK
+ bool
+ default n
+
# Timekeeping vsyscall support
config GENERIC_TIME_VSYSCALL
bool
@@ -38,6 +43,10 @@ config GENERIC_CLOCKEVENTS_BUILD
default y
depends on GENERIC_CLOCKEVENTS
+# Architecture can handle broadcast in a driver-agnostic way
+config ARCH_HAS_TICK_BROADCAST
+ bool
+
# Clockevents broadcasting infrastructure
config GENERIC_CLOCKEVENTS_BROADCAST
bool
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 24174b4d669..b10a42bb016 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -15,6 +15,7 @@
#include <linux/time.h>
#include <linux/mm.h>
#include <linux/module.h>
+#include <linux/rtc.h>
#include "tick-internal.h"
@@ -483,8 +484,7 @@ out:
return leap;
}
-#ifdef CONFIG_GENERIC_CMOS_UPDATE
-
+#if defined(CONFIG_GENERIC_CMOS_UPDATE) || defined(CONFIG_RTC_SYSTOHC)
static void sync_cmos_clock(struct work_struct *work);
static DECLARE_DELAYED_WORK(sync_cmos_work, sync_cmos_clock);
@@ -510,14 +510,26 @@ static void sync_cmos_clock(struct work_struct *work)
}
getnstimeofday(&now);
- if (abs(now.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec / 2)
- fail = update_persistent_clock(now);
+ if (abs(now.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec / 2) {
+ struct timespec adjust = now;
+
+ fail = -ENODEV;
+ if (persistent_clock_is_local)
+ adjust.tv_sec -= (sys_tz.tz_minuteswest * 60);
+#ifdef CONFIG_GENERIC_CMOS_UPDATE
+ fail = update_persistent_clock(adjust);
+#endif
+#ifdef CONFIG_RTC_SYSTOHC
+ if (fail == -ENODEV)
+ fail = rtc_set_ntp_time(adjust);
+#endif
+ }
next.tv_nsec = (NSEC_PER_SEC / 2) - now.tv_nsec - (TICK_NSEC / 2);
if (next.tv_nsec <= 0)
next.tv_nsec += NSEC_PER_SEC;
- if (!fail)
+ if (!fail || fail == -ENODEV)
next.tv_sec = 659;
else
next.tv_sec = 0;
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index f113755695e..2fb8cb88df8 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -18,6 +18,7 @@
#include <linux/percpu.h>
#include <linux/profile.h>
#include <linux/sched.h>
+#include <linux/smp.h>
#include "tick-internal.h"
@@ -86,6 +87,22 @@ int tick_is_broadcast_device(struct clock_event_device *dev)
return (dev && tick_broadcast_device.evtdev == dev);
}
+static void err_broadcast(const struct cpumask *mask)
+{
+ pr_crit_once("Failed to broadcast timer tick. Some CPUs may be unresponsive.\n");
+}
+
+static void tick_device_setup_broadcast_func(struct clock_event_device *dev)
+{
+ if (!dev->broadcast)
+ dev->broadcast = tick_broadcast;
+ if (!dev->broadcast) {
+ pr_warn_once("%s depends on broadcast, but no broadcast function available\n",
+ dev->name);
+ dev->broadcast = err_broadcast;
+ }
+}
+
/*
* Check, if the device is disfunctional and a place holder, which
* needs to be handled by the broadcast device.
@@ -105,6 +122,7 @@ int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu)
*/
if (!tick_device_is_functional(dev)) {
dev->event_handler = tick_handle_periodic;
+ tick_device_setup_broadcast_func(dev);
cpumask_set_cpu(cpu, tick_get_broadcast_mask());
tick_broadcast_start_periodic(tick_broadcast_device.evtdev);
ret = 1;
@@ -116,15 +134,33 @@ int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu)
*/
if (!(dev->features & CLOCK_EVT_FEAT_C3STOP)) {
int cpu = smp_processor_id();
-
cpumask_clear_cpu(cpu, tick_get_broadcast_mask());
tick_broadcast_clear_oneshot(cpu);
+ } else {
+ tick_device_setup_broadcast_func(dev);
}
}
raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
return ret;
}
+#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
+int tick_receive_broadcast(void)
+{
+ struct tick_device *td = this_cpu_ptr(&tick_cpu_device);
+ struct clock_event_device *evt = td->evtdev;
+
+ if (!evt)
+ return -ENODEV;
+
+ if (!evt->event_handler)
+ return -EINVAL;
+
+ evt->event_handler(evt);
+ return 0;
+}
+#endif
+
/*
* Broadcast the event to the cpus, which are set in the mask (mangled).
*/
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index d58e552d9fd..314b9ee07ed 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -20,6 +20,7 @@
#include <linux/profile.h>
#include <linux/sched.h>
#include <linux/module.h>
+#include <linux/irq_work.h>
#include <asm/irq_regs.h>
@@ -28,7 +29,7 @@
/*
* Per cpu nohz control structure
*/
-static DEFINE_PER_CPU(struct tick_sched, tick_cpu_sched);
+DEFINE_PER_CPU(struct tick_sched, tick_cpu_sched);
/*
* The time, when the last jiffy update happened. Protected by jiffies_lock.
@@ -331,8 +332,8 @@ static ktime_t tick_nohz_stop_sched_tick(struct tick_sched *ts,
time_delta = timekeeping_max_deferment();
} while (read_seqretry(&jiffies_lock, seq));
- if (rcu_needs_cpu(cpu, &rcu_delta_jiffies) || printk_needs_cpu(cpu) ||
- arch_needs_cpu(cpu)) {
+ if (rcu_needs_cpu(cpu, &rcu_delta_jiffies) ||
+ arch_needs_cpu(cpu) || irq_work_needs_cpu()) {
next_jiffies = last_jiffies + 1;
delta_jiffies = 1;
} else {
@@ -631,8 +632,11 @@ static void tick_nohz_restart_sched_tick(struct tick_sched *ts, ktime_t now)
static void tick_nohz_account_idle_ticks(struct tick_sched *ts)
{
-#ifndef CONFIG_VIRT_CPU_ACCOUNTING
+#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
unsigned long ticks;
+
+ if (vtime_accounting_enabled())
+ return;
/*
* We stopped the tick in idle. Update process times would miss the
* time we slept as update_process_times does only a 1 tick
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index cbc6acb0db3..1e35515a875 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -29,6 +29,9 @@ static struct timekeeper timekeeper;
/* flag for if timekeeping is suspended */
int __read_mostly timekeeping_suspended;
+/* Flag for if there is a persistent clock on this platform */
+bool __read_mostly persistent_clock_exist = false;
+
static inline void tk_normalize_xtime(struct timekeeper *tk)
{
while (tk->xtime_nsec >= ((u64)NSEC_PER_SEC << tk->shift)) {
@@ -264,19 +267,18 @@ static void timekeeping_forward_now(struct timekeeper *tk)
}
/**
- * getnstimeofday - Returns the time of day in a timespec
+ * __getnstimeofday - Returns the time of day in a timespec.
* @ts: pointer to the timespec to be set
*
- * Returns the time of day in a timespec.
+ * Updates the time of day in the timespec.
+ * Returns 0 on success, or -ve when suspended (timespec will be undefined).
*/
-void getnstimeofday(struct timespec *ts)
+int __getnstimeofday(struct timespec *ts)
{
struct timekeeper *tk = &timekeeper;
unsigned long seq;
s64 nsecs = 0;
- WARN_ON(timekeeping_suspended);
-
do {
seq = read_seqbegin(&tk->lock);
@@ -287,6 +289,26 @@ void getnstimeofday(struct timespec *ts)
ts->tv_nsec = 0;
timespec_add_ns(ts, nsecs);
+
+ /*
+ * Do not bail out early, in case there were callers still using
+ * the value, even in the face of the WARN_ON.
+ */
+ if (unlikely(timekeeping_suspended))
+ return -EAGAIN;
+ return 0;
+}
+EXPORT_SYMBOL(__getnstimeofday);
+
+/**
+ * getnstimeofday - Returns the time of day in a timespec.
+ * @ts: pointer to the timespec to be set
+ *
+ * Returns the time of day in a timespec (WARN if suspended).
+ */
+void getnstimeofday(struct timespec *ts)
+{
+ WARN_ON(__getnstimeofday(ts));
}
EXPORT_SYMBOL(getnstimeofday);
@@ -640,12 +662,14 @@ void __init timekeeping_init(void)
struct timespec now, boot, tmp;
read_persistent_clock(&now);
+
if (!timespec_valid_strict(&now)) {
pr_warn("WARNING: Persistent clock returned invalid value!\n"
" Check your CMOS/BIOS settings.\n");
now.tv_sec = 0;
now.tv_nsec = 0;
- }
+ } else if (now.tv_sec || now.tv_nsec)
+ persistent_clock_exist = true;
read_boot_clock(&boot);
if (!timespec_valid_strict(&boot)) {
@@ -718,11 +742,12 @@ void timekeeping_inject_sleeptime(struct timespec *delta)
{
struct timekeeper *tk = &timekeeper;
unsigned long flags;
- struct timespec ts;
- /* Make sure we don't set the clock twice */
- read_persistent_clock(&ts);
- if (!(ts.tv_sec == 0 && ts.tv_nsec == 0))
+ /*
+ * Make sure we don't set the clock twice, as timekeeping_resume()
+ * already did it
+ */
+ if (has_persistent_clock())
return;
write_seqlock_irqsave(&tk->lock, flags);
diff --git a/kernel/timeconst.pl b/kernel/timeconst.pl
index eb51d76e058..3f42652a6a3 100644
--- a/kernel/timeconst.pl
+++ b/kernel/timeconst.pl
@@ -369,10 +369,8 @@ if ($hz eq '--can') {
die "Usage: $0 HZ\n";
}
- @val = @{$canned_values{$hz}};
- if (!defined(@val)) {
- @val = compute_values($hz);
- }
+ $cv = $canned_values{$hz};
+ @val = defined($cv) ? @$cv : compute_values($hz);
output($hz, @val);
}
exit 0;
diff --git a/kernel/timer.c b/kernel/timer.c
index 367d0085848..dbf7a78a1ef 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -39,6 +39,7 @@
#include <linux/kallsyms.h>
#include <linux/irq_work.h>
#include <linux/sched.h>
+#include <linux/sched/sysctl.h>
#include <linux/slab.h>
#include <asm/uaccess.h>
@@ -1351,7 +1352,6 @@ void update_process_times(int user_tick)
account_process_tick(p, user_tick);
run_local_timers();
rcu_check_callbacks(cpu, user_tick);
- printk_tick();
#ifdef CONFIG_IRQ_WORK
if (in_irq())
irq_work_run();
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 5d89335a485..36567564e22 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -39,6 +39,9 @@ config HAVE_DYNAMIC_FTRACE
help
See Documentation/trace/ftrace-design.txt
+config HAVE_DYNAMIC_FTRACE_WITH_REGS
+ bool
+
config HAVE_FTRACE_MCOUNT_RECORD
bool
help
@@ -250,6 +253,16 @@ config FTRACE_SYSCALLS
help
Basic tracer to catch the syscall entry and exit events.
+config TRACER_SNAPSHOT
+ bool "Create a snapshot trace buffer"
+ select TRACER_MAX_TRACE
+ help
+ Allow tracing users to take snapshot of the current buffer using the
+ ftrace interface, e.g.:
+
+ echo 1 > /sys/kernel/debug/tracing/snapshot
+ cat snapshot
+
config TRACE_BRANCH_PROFILING
bool
select GENERIC_TRACER
@@ -434,6 +447,11 @@ config DYNAMIC_FTRACE
were made. If so, it runs stop_machine (stops all CPUS)
and modifies the code to jump over the call to ftrace.
+config DYNAMIC_FTRACE_WITH_REGS
+ def_bool y
+ depends on DYNAMIC_FTRACE
+ depends on HAVE_DYNAMIC_FTRACE_WITH_REGS
+
config FUNCTION_PROFILER
bool "Kernel function profiler"
depends on FUNCTION_TRACER
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index c0bd0308741..71259e2b6b6 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -147,7 +147,7 @@ void __trace_note_message(struct blk_trace *bt, const char *fmt, ...)
return;
local_irq_save(flags);
- buf = per_cpu_ptr(bt->msg_data, smp_processor_id());
+ buf = this_cpu_ptr(bt->msg_data);
va_start(args, fmt);
n = vscnprintf(buf, BLK_TN_MAX_MSG, fmt, args);
va_end(args);
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 3ffe4c5ad3f..ce8c3d68292 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -111,6 +111,26 @@ static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip);
#define ftrace_ops_list_func ((ftrace_func_t)ftrace_ops_no_ops)
#endif
+/*
+ * Traverse the ftrace_global_list, invoking all entries. The reason that we
+ * can use rcu_dereference_raw() is that elements removed from this list
+ * are simply leaked, so there is no need to interact with a grace-period
+ * mechanism. The rcu_dereference_raw() calls are needed to handle
+ * concurrent insertions into the ftrace_global_list.
+ *
+ * Silly Alpha and silly pointer-speculation compiler optimizations!
+ */
+#define do_for_each_ftrace_op(op, list) \
+ op = rcu_dereference_raw(list); \
+ do
+
+/*
+ * Optimized for just a single item in the list (as that is the normal case).
+ */
+#define while_for_each_ftrace_op(op) \
+ while (likely(op = rcu_dereference_raw((op)->next)) && \
+ unlikely((op) != &ftrace_list_end))
+
/**
* ftrace_nr_registered_ops - return number of ops registered
*
@@ -132,29 +152,21 @@ int ftrace_nr_registered_ops(void)
return cnt;
}
-/*
- * Traverse the ftrace_global_list, invoking all entries. The reason that we
- * can use rcu_dereference_raw() is that elements removed from this list
- * are simply leaked, so there is no need to interact with a grace-period
- * mechanism. The rcu_dereference_raw() calls are needed to handle
- * concurrent insertions into the ftrace_global_list.
- *
- * Silly Alpha and silly pointer-speculation compiler optimizations!
- */
static void
ftrace_global_list_func(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct pt_regs *regs)
{
- if (unlikely(trace_recursion_test(TRACE_GLOBAL_BIT)))
+ int bit;
+
+ bit = trace_test_and_set_recursion(TRACE_GLOBAL_START, TRACE_GLOBAL_MAX);
+ if (bit < 0)
return;
- trace_recursion_set(TRACE_GLOBAL_BIT);
- op = rcu_dereference_raw(ftrace_global_list); /*see above*/
- while (op != &ftrace_list_end) {
+ do_for_each_ftrace_op(op, ftrace_global_list) {
op->func(ip, parent_ip, op, regs);
- op = rcu_dereference_raw(op->next); /*see above*/
- };
- trace_recursion_clear(TRACE_GLOBAL_BIT);
+ } while_for_each_ftrace_op(op);
+
+ trace_clear_recursion(bit);
}
static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip,
@@ -221,10 +233,24 @@ static void update_global_ops(void)
* registered callers.
*/
if (ftrace_global_list == &ftrace_list_end ||
- ftrace_global_list->next == &ftrace_list_end)
+ ftrace_global_list->next == &ftrace_list_end) {
func = ftrace_global_list->func;
- else
+ /*
+ * As we are calling the function directly.
+ * If it does not have recursion protection,
+ * the function_trace_op needs to be updated
+ * accordingly.
+ */
+ if (ftrace_global_list->flags & FTRACE_OPS_FL_RECURSION_SAFE)
+ global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE;
+ else
+ global_ops.flags &= ~FTRACE_OPS_FL_RECURSION_SAFE;
+ } else {
func = ftrace_global_list_func;
+ /* The list has its own recursion protection. */
+ global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE;
+ }
+
/* If we filter on pids, update to use the pid function */
if (!list_empty(&ftrace_pids)) {
@@ -337,7 +363,7 @@ static int __register_ftrace_function(struct ftrace_ops *ops)
if ((ops->flags & FL_GLOBAL_CONTROL_MASK) == FL_GLOBAL_CONTROL_MASK)
return -EINVAL;
-#ifndef ARCH_SUPPORTS_FTRACE_SAVE_REGS
+#ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS
/*
* If the ftrace_ops specifies SAVE_REGS, then it only can be used
* if the arch supports it, or SAVE_REGS_IF_SUPPORTED is also set.
@@ -3998,7 +4024,7 @@ static int ftrace_module_notify(struct notifier_block *self,
struct notifier_block ftrace_module_nb = {
.notifier_call = ftrace_module_notify,
- .priority = 0,
+ .priority = INT_MAX, /* Run before anything that can use kprobes */
};
extern unsigned long __start_mcount_loc[];
@@ -4090,14 +4116,11 @@ ftrace_ops_control_func(unsigned long ip, unsigned long parent_ip,
*/
preempt_disable_notrace();
trace_recursion_set(TRACE_CONTROL_BIT);
- op = rcu_dereference_raw(ftrace_control_list);
- while (op != &ftrace_list_end) {
+ do_for_each_ftrace_op(op, ftrace_control_list) {
if (!ftrace_function_local_disabled(op) &&
ftrace_ops_test(op, ip))
op->func(ip, parent_ip, op, regs);
-
- op = rcu_dereference_raw(op->next);
- };
+ } while_for_each_ftrace_op(op);
trace_recursion_clear(TRACE_CONTROL_BIT);
preempt_enable_notrace();
}
@@ -4112,27 +4135,26 @@ __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *ignored, struct pt_regs *regs)
{
struct ftrace_ops *op;
+ int bit;
if (function_trace_stop)
return;
- if (unlikely(trace_recursion_test(TRACE_INTERNAL_BIT)))
+ bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX);
+ if (bit < 0)
return;
- trace_recursion_set(TRACE_INTERNAL_BIT);
/*
* Some of the ops may be dynamically allocated,
* they must be freed after a synchronize_sched().
*/
preempt_disable_notrace();
- op = rcu_dereference_raw(ftrace_ops_list);
- while (op != &ftrace_list_end) {
+ do_for_each_ftrace_op(op, ftrace_ops_list) {
if (ftrace_ops_test(op, ip))
op->func(ip, parent_ip, op, regs);
- op = rcu_dereference_raw(op->next);
- };
+ } while_for_each_ftrace_op(op);
preempt_enable_notrace();
- trace_recursion_clear(TRACE_INTERNAL_BIT);
+ trace_clear_recursion(bit);
}
/*
@@ -4143,8 +4165,8 @@ __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip,
* Archs are to support both the regs and ftrace_ops at the same time.
* If they support ftrace_ops, it is assumed they support regs.
* If call backs want to use regs, they must either check for regs
- * being NULL, or ARCH_SUPPORTS_FTRACE_SAVE_REGS.
- * Note, ARCH_SUPPORT_SAVE_REGS expects a full regs to be saved.
+ * being NULL, or CONFIG_DYNAMIC_FTRACE_WITH_REGS.
+ * Note, CONFIG_DYNAMIC_FTRACE_WITH_REGS expects a full regs to be saved.
* An architecture can pass partial regs with ftrace_ops and still
* set the ARCH_SUPPORT_FTARCE_OPS.
*/
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index ce8514feedc..7244acde77b 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -3,8 +3,10 @@
*
* Copyright (C) 2008 Steven Rostedt <srostedt@redhat.com>
*/
+#include <linux/ftrace_event.h>
#include <linux/ring_buffer.h>
#include <linux/trace_clock.h>
+#include <linux/trace_seq.h>
#include <linux/spinlock.h>
#include <linux/debugfs.h>
#include <linux/uaccess.h>
@@ -21,7 +23,6 @@
#include <linux/fs.h>
#include <asm/local.h>
-#include "trace.h"
static void update_pages_handler(struct work_struct *work);
@@ -2432,41 +2433,76 @@ rb_reserve_next_event(struct ring_buffer *buffer,
#ifdef CONFIG_TRACING
-#define TRACE_RECURSIVE_DEPTH 16
+/*
+ * The lock and unlock are done within a preempt disable section.
+ * The current_context per_cpu variable can only be modified
+ * by the current task between lock and unlock. But it can
+ * be modified more than once via an interrupt. To pass this
+ * information from the lock to the unlock without having to
+ * access the 'in_interrupt()' functions again (which do show
+ * a bit of overhead in something as critical as function tracing,
+ * we use a bitmask trick.
+ *
+ * bit 0 = NMI context
+ * bit 1 = IRQ context
+ * bit 2 = SoftIRQ context
+ * bit 3 = normal context.
+ *
+ * This works because this is the order of contexts that can
+ * preempt other contexts. A SoftIRQ never preempts an IRQ
+ * context.
+ *
+ * When the context is determined, the corresponding bit is
+ * checked and set (if it was set, then a recursion of that context
+ * happened).
+ *
+ * On unlock, we need to clear this bit. To do so, just subtract
+ * 1 from the current_context and AND it to itself.
+ *
+ * (binary)
+ * 101 - 1 = 100
+ * 101 & 100 = 100 (clearing bit zero)
+ *
+ * 1010 - 1 = 1001
+ * 1010 & 1001 = 1000 (clearing bit 1)
+ *
+ * The least significant bit can be cleared this way, and it
+ * just so happens that it is the same bit corresponding to
+ * the current context.
+ */
+static DEFINE_PER_CPU(unsigned int, current_context);
-/* Keep this code out of the fast path cache */
-static noinline void trace_recursive_fail(void)
+static __always_inline int trace_recursive_lock(void)
{
- /* Disable all tracing before we do anything else */
- tracing_off_permanent();
-
- printk_once(KERN_WARNING "Tracing recursion: depth[%ld]:"
- "HC[%lu]:SC[%lu]:NMI[%lu]\n",
- trace_recursion_buffer(),
- hardirq_count() >> HARDIRQ_SHIFT,
- softirq_count() >> SOFTIRQ_SHIFT,
- in_nmi());
-
- WARN_ON_ONCE(1);
-}
+ unsigned int val = this_cpu_read(current_context);
+ int bit;
-static inline int trace_recursive_lock(void)
-{
- trace_recursion_inc();
+ if (in_interrupt()) {
+ if (in_nmi())
+ bit = 0;
+ else if (in_irq())
+ bit = 1;
+ else
+ bit = 2;
+ } else
+ bit = 3;
- if (likely(trace_recursion_buffer() < TRACE_RECURSIVE_DEPTH))
- return 0;
+ if (unlikely(val & (1 << bit)))
+ return 1;
- trace_recursive_fail();
+ val |= (1 << bit);
+ this_cpu_write(current_context, val);
- return -1;
+ return 0;
}
-static inline void trace_recursive_unlock(void)
+static __always_inline void trace_recursive_unlock(void)
{
- WARN_ON_ONCE(!trace_recursion_buffer());
+ unsigned int val = this_cpu_read(current_context);
- trace_recursion_dec();
+ val--;
+ val &= this_cpu_read(current_context);
+ this_cpu_write(current_context, val);
}
#else
@@ -3067,6 +3103,24 @@ ring_buffer_dropped_events_cpu(struct ring_buffer *buffer, int cpu)
EXPORT_SYMBOL_GPL(ring_buffer_dropped_events_cpu);
/**
+ * ring_buffer_read_events_cpu - get the number of events successfully read
+ * @buffer: The ring buffer
+ * @cpu: The per CPU buffer to get the number of events read
+ */
+unsigned long
+ring_buffer_read_events_cpu(struct ring_buffer *buffer, int cpu)
+{
+ struct ring_buffer_per_cpu *cpu_buffer;
+
+ if (!cpumask_test_cpu(cpu, buffer->cpumask))
+ return 0;
+
+ cpu_buffer = buffer->buffers[cpu];
+ return cpu_buffer->read;
+}
+EXPORT_SYMBOL_GPL(ring_buffer_read_events_cpu);
+
+/**
* ring_buffer_entries - get the number of entries in a buffer
* @buffer: The ring buffer
*
@@ -3425,7 +3479,7 @@ static void rb_advance_iter(struct ring_buffer_iter *iter)
/* check for end of page padding */
if ((iter->head >= rb_page_size(iter->head_page)) &&
(iter->head_page != cpu_buffer->commit_page))
- rb_advance_iter(iter);
+ rb_inc_iter(iter);
}
static int rb_lost_events(struct ring_buffer_per_cpu *cpu_buffer)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index e5125677efa..c2e2c231037 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -39,6 +39,7 @@
#include <linux/poll.h>
#include <linux/nmi.h>
#include <linux/fs.h>
+#include <linux/sched/rt.h>
#include "trace.h"
#include "trace_output.h"
@@ -249,7 +250,7 @@ static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT;
static struct tracer *trace_types __read_mostly;
/* current_trace points to the tracer that is currently active */
-static struct tracer *current_trace __read_mostly;
+static struct tracer *current_trace __read_mostly = &nop_trace;
/*
* trace_types_lock is used to protect the trace_types list.
@@ -709,10 +710,13 @@ update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
return;
WARN_ON_ONCE(!irqs_disabled());
- if (!current_trace->use_max_tr) {
- WARN_ON_ONCE(1);
+
+ if (!current_trace->allocated_snapshot) {
+ /* Only the nop tracer should hit this when disabling */
+ WARN_ON_ONCE(current_trace != &nop_trace);
return;
}
+
arch_spin_lock(&ftrace_max_lock);
tr->buffer = max_tr.buffer;
@@ -739,10 +743,8 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
return;
WARN_ON_ONCE(!irqs_disabled());
- if (!current_trace->use_max_tr) {
- WARN_ON_ONCE(1);
+ if (WARN_ON_ONCE(!current_trace->allocated_snapshot))
return;
- }
arch_spin_lock(&ftrace_max_lock);
@@ -862,10 +864,13 @@ int register_tracer(struct tracer *type)
current_trace = type;
- /* If we expanded the buffers, make sure the max is expanded too */
- if (ring_buffer_expanded && type->use_max_tr)
- ring_buffer_resize(max_tr.buffer, trace_buf_size,
- RING_BUFFER_ALL_CPUS);
+ if (type->use_max_tr) {
+ /* If we expanded the buffers, make sure the max is expanded too */
+ if (ring_buffer_expanded)
+ ring_buffer_resize(max_tr.buffer, trace_buf_size,
+ RING_BUFFER_ALL_CPUS);
+ type->allocated_snapshot = true;
+ }
/* the test is responsible for initializing and enabling */
pr_info("Testing tracer %s: ", type->name);
@@ -881,10 +886,14 @@ int register_tracer(struct tracer *type)
/* Only reset on passing, to avoid touching corrupted buffers */
tracing_reset_online_cpus(tr);
- /* Shrink the max buffer again */
- if (ring_buffer_expanded && type->use_max_tr)
- ring_buffer_resize(max_tr.buffer, 1,
- RING_BUFFER_ALL_CPUS);
+ if (type->use_max_tr) {
+ type->allocated_snapshot = false;
+
+ /* Shrink the max buffer again */
+ if (ring_buffer_expanded)
+ ring_buffer_resize(max_tr.buffer, 1,
+ RING_BUFFER_ALL_CPUS);
+ }
printk(KERN_CONT "PASSED\n");
}
@@ -922,6 +931,9 @@ void tracing_reset(struct trace_array *tr, int cpu)
{
struct ring_buffer *buffer = tr->buffer;
+ if (!buffer)
+ return;
+
ring_buffer_record_disable(buffer);
/* Make sure all commits have finished */
@@ -936,6 +948,9 @@ void tracing_reset_online_cpus(struct trace_array *tr)
struct ring_buffer *buffer = tr->buffer;
int cpu;
+ if (!buffer)
+ return;
+
ring_buffer_record_disable(buffer);
/* Make sure all commits have finished */
@@ -1167,7 +1182,6 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
entry->preempt_count = pc & 0xff;
entry->pid = (tsk) ? tsk->pid : 0;
- entry->padding = 0;
entry->flags =
#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
(irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) |
@@ -1335,7 +1349,7 @@ static void __ftrace_trace_stack(struct ring_buffer *buffer,
*/
preempt_disable_notrace();
- use_stack = ++__get_cpu_var(ftrace_stack_reserve);
+ use_stack = __this_cpu_inc_return(ftrace_stack_reserve);
/*
* We don't need any atomic variables, just a barrier.
* If an interrupt comes in, we don't care, because it would
@@ -1389,7 +1403,7 @@ static void __ftrace_trace_stack(struct ring_buffer *buffer,
out:
/* Again, don't let gcc optimize things here */
barrier();
- __get_cpu_var(ftrace_stack_reserve)--;
+ __this_cpu_dec(ftrace_stack_reserve);
preempt_enable_notrace();
}
@@ -1517,7 +1531,6 @@ static struct trace_buffer_struct *trace_percpu_nmi_buffer;
static char *get_trace_buf(void)
{
struct trace_buffer_struct *percpu_buffer;
- struct trace_buffer_struct *buffer;
/*
* If we have allocated per cpu buffers, then we do not
@@ -1535,9 +1548,7 @@ static char *get_trace_buf(void)
if (!percpu_buffer)
return NULL;
- buffer = per_cpu_ptr(percpu_buffer, smp_processor_id());
-
- return buffer->buffer;
+ return this_cpu_ptr(&percpu_buffer->buffer[0]);
}
static int alloc_percpu_trace_buffer(void)
@@ -1942,21 +1953,27 @@ void tracing_iter_reset(struct trace_iterator *iter, int cpu)
static void *s_start(struct seq_file *m, loff_t *pos)
{
struct trace_iterator *iter = m->private;
- static struct tracer *old_tracer;
int cpu_file = iter->cpu_file;
void *p = NULL;
loff_t l = 0;
int cpu;
- /* copy the tracer to avoid using a global lock all around */
+ /*
+ * copy the tracer to avoid using a global lock all around.
+ * iter->trace is a copy of current_trace, the pointer to the
+ * name may be used instead of a strcmp(), as iter->trace->name
+ * will point to the same string as current_trace->name.
+ */
mutex_lock(&trace_types_lock);
- if (unlikely(old_tracer != current_trace && current_trace)) {
- old_tracer = current_trace;
+ if (unlikely(current_trace && iter->trace->name != current_trace->name))
*iter->trace = *current_trace;
- }
mutex_unlock(&trace_types_lock);
- atomic_inc(&trace_record_cmdline_disabled);
+ if (iter->snapshot && iter->trace->use_max_tr)
+ return ERR_PTR(-EBUSY);
+
+ if (!iter->snapshot)
+ atomic_inc(&trace_record_cmdline_disabled);
if (*pos != iter->pos) {
iter->ent = NULL;
@@ -1995,7 +2012,11 @@ static void s_stop(struct seq_file *m, void *p)
{
struct trace_iterator *iter = m->private;
- atomic_dec(&trace_record_cmdline_disabled);
+ if (iter->snapshot && iter->trace->use_max_tr)
+ return;
+
+ if (!iter->snapshot)
+ atomic_dec(&trace_record_cmdline_disabled);
trace_access_unlock(iter->cpu_file);
trace_event_read_unlock();
}
@@ -2080,8 +2101,7 @@ print_trace_header(struct seq_file *m, struct trace_iterator *iter)
unsigned long total;
const char *name = "preemption";
- if (type)
- name = type->name;
+ name = type->name;
get_total_entries(tr, &total, &entries);
@@ -2430,7 +2450,7 @@ static const struct seq_operations tracer_seq_ops = {
};
static struct trace_iterator *
-__tracing_open(struct inode *inode, struct file *file)
+__tracing_open(struct inode *inode, struct file *file, bool snapshot)
{
long cpu_file = (long) inode->i_private;
struct trace_iterator *iter;
@@ -2457,16 +2477,16 @@ __tracing_open(struct inode *inode, struct file *file)
if (!iter->trace)
goto fail;
- if (current_trace)
- *iter->trace = *current_trace;
+ *iter->trace = *current_trace;
if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL))
goto fail;
- if (current_trace && current_trace->print_max)
+ if (current_trace->print_max || snapshot)
iter->tr = &max_tr;
else
iter->tr = &global_trace;
+ iter->snapshot = snapshot;
iter->pos = -1;
mutex_init(&iter->mutex);
iter->cpu_file = cpu_file;
@@ -2483,8 +2503,9 @@ __tracing_open(struct inode *inode, struct file *file)
if (trace_clocks[trace_clock_id].in_ns)
iter->iter_flags |= TRACE_FILE_TIME_IN_NS;
- /* stop the trace while dumping */
- tracing_stop();
+ /* stop the trace while dumping if we are not opening "snapshot" */
+ if (!iter->snapshot)
+ tracing_stop();
if (iter->cpu_file == TRACE_PIPE_ALL_CPU) {
for_each_tracing_cpu(cpu) {
@@ -2547,8 +2568,9 @@ static int tracing_release(struct inode *inode, struct file *file)
if (iter->trace && iter->trace->close)
iter->trace->close(iter);
- /* reenable tracing if it was previously enabled */
- tracing_start();
+ if (!iter->snapshot)
+ /* reenable tracing if it was previously enabled */
+ tracing_start();
mutex_unlock(&trace_types_lock);
mutex_destroy(&iter->mutex);
@@ -2576,7 +2598,7 @@ static int tracing_open(struct inode *inode, struct file *file)
}
if (file->f_mode & FMODE_READ) {
- iter = __tracing_open(inode, file);
+ iter = __tracing_open(inode, file, false);
if (IS_ERR(iter))
ret = PTR_ERR(iter);
else if (trace_flags & TRACE_ITER_LATENCY_FMT)
@@ -2899,6 +2921,8 @@ tracing_trace_options_write(struct file *filp, const char __user *ubuf,
if (copy_from_user(&buf, ubuf, cnt))
return -EFAULT;
+ buf[cnt] = 0;
+
trace_set_options(buf);
*ppos += cnt;
@@ -3012,10 +3036,7 @@ tracing_set_trace_read(struct file *filp, char __user *ubuf,
int r;
mutex_lock(&trace_types_lock);
- if (current_trace)
- r = sprintf(buf, "%s\n", current_trace->name);
- else
- r = sprintf(buf, "\n");
+ r = sprintf(buf, "%s\n", current_trace->name);
mutex_unlock(&trace_types_lock);
return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
@@ -3181,6 +3202,7 @@ static int tracing_set_tracer(const char *buf)
static struct trace_option_dentry *topts;
struct trace_array *tr = &global_trace;
struct tracer *t;
+ bool had_max_tr;
int ret = 0;
mutex_lock(&trace_types_lock);
@@ -3205,9 +3227,21 @@ static int tracing_set_tracer(const char *buf)
goto out;
trace_branch_disable();
- if (current_trace && current_trace->reset)
+ if (current_trace->reset)
current_trace->reset(tr);
- if (current_trace && current_trace->use_max_tr) {
+
+ had_max_tr = current_trace->allocated_snapshot;
+ current_trace = &nop_trace;
+
+ if (had_max_tr && !t->use_max_tr) {
+ /*
+ * We need to make sure that the update_max_tr sees that
+ * current_trace changed to nop_trace to keep it from
+ * swapping the buffers after we resize it.
+ * The update_max_tr is called from interrupts disabled
+ * so a synchronized_sched() is sufficient.
+ */
+ synchronize_sched();
/*
* We don't free the ring buffer. instead, resize it because
* The max_tr ring buffer has some state (e.g. ring->clock) and
@@ -3215,18 +3249,19 @@ static int tracing_set_tracer(const char *buf)
*/
ring_buffer_resize(max_tr.buffer, 1, RING_BUFFER_ALL_CPUS);
set_buffer_entries(&max_tr, 1);
+ tracing_reset_online_cpus(&max_tr);
+ current_trace->allocated_snapshot = false;
}
destroy_trace_option_files(topts);
- current_trace = &nop_trace;
-
topts = create_trace_option_files(t);
- if (t->use_max_tr) {
+ if (t->use_max_tr && !had_max_tr) {
/* we need to make per cpu buffer sizes equivalent */
ret = resize_buffer_duplicate_size(&max_tr, &global_trace,
RING_BUFFER_ALL_CPUS);
if (ret < 0)
goto out;
+ t->allocated_snapshot = true;
}
if (t->init) {
@@ -3334,8 +3369,7 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp)
ret = -ENOMEM;
goto fail;
}
- if (current_trace)
- *iter->trace = *current_trace;
+ *iter->trace = *current_trace;
if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) {
ret = -ENOMEM;
@@ -3452,7 +3486,7 @@ static int tracing_wait_pipe(struct file *filp)
return -EINTR;
/*
- * We block until we read something and tracing is enabled.
+ * We block until we read something and tracing is disabled.
* We still block if tracing is disabled, but we have never
* read anything. This allows a user to cat this file, and
* then enable tracing. But after we have read something,
@@ -3460,7 +3494,7 @@ static int tracing_wait_pipe(struct file *filp)
*
* iter->pos will be 0 if we haven't read anything.
*/
- if (tracing_is_enabled() && iter->pos)
+ if (!tracing_is_enabled() && iter->pos)
break;
}
@@ -3475,7 +3509,6 @@ tracing_read_pipe(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
{
struct trace_iterator *iter = filp->private_data;
- static struct tracer *old_tracer;
ssize_t sret;
/* return any leftover data */
@@ -3487,10 +3520,8 @@ tracing_read_pipe(struct file *filp, char __user *ubuf,
/* copy the tracer to avoid using a global lock all around */
mutex_lock(&trace_types_lock);
- if (unlikely(old_tracer != current_trace && current_trace)) {
- old_tracer = current_trace;
+ if (unlikely(iter->trace->name != current_trace->name))
*iter->trace = *current_trace;
- }
mutex_unlock(&trace_types_lock);
/*
@@ -3646,7 +3677,6 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
.ops = &tracing_pipe_buf_ops,
.spd_release = tracing_spd_release_pipe,
};
- static struct tracer *old_tracer;
ssize_t ret;
size_t rem;
unsigned int i;
@@ -3656,10 +3686,8 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
/* copy the tracer to avoid using a global lock all around */
mutex_lock(&trace_types_lock);
- if (unlikely(old_tracer != current_trace && current_trace)) {
- old_tracer = current_trace;
+ if (unlikely(iter->trace->name != current_trace->name))
*iter->trace = *current_trace;
- }
mutex_unlock(&trace_types_lock);
mutex_lock(&iter->mutex);
@@ -4035,8 +4063,7 @@ static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf,
* Reset the buffer so that it doesn't have incomparable timestamps.
*/
tracing_reset_online_cpus(&global_trace);
- if (max_tr.buffer)
- tracing_reset_online_cpus(&max_tr);
+ tracing_reset_online_cpus(&max_tr);
mutex_unlock(&trace_types_lock);
@@ -4052,6 +4079,87 @@ static int tracing_clock_open(struct inode *inode, struct file *file)
return single_open(file, tracing_clock_show, NULL);
}
+#ifdef CONFIG_TRACER_SNAPSHOT
+static int tracing_snapshot_open(struct inode *inode, struct file *file)
+{
+ struct trace_iterator *iter;
+ int ret = 0;
+
+ if (file->f_mode & FMODE_READ) {
+ iter = __tracing_open(inode, file, true);
+ if (IS_ERR(iter))
+ ret = PTR_ERR(iter);
+ }
+ return ret;
+}
+
+static ssize_t
+tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ unsigned long val;
+ int ret;
+
+ ret = tracing_update_buffers();
+ if (ret < 0)
+ return ret;
+
+ ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
+ if (ret)
+ return ret;
+
+ mutex_lock(&trace_types_lock);
+
+ if (current_trace->use_max_tr) {
+ ret = -EBUSY;
+ goto out;
+ }
+
+ switch (val) {
+ case 0:
+ if (current_trace->allocated_snapshot) {
+ /* free spare buffer */
+ ring_buffer_resize(max_tr.buffer, 1,
+ RING_BUFFER_ALL_CPUS);
+ set_buffer_entries(&max_tr, 1);
+ tracing_reset_online_cpus(&max_tr);
+ current_trace->allocated_snapshot = false;
+ }
+ break;
+ case 1:
+ if (!current_trace->allocated_snapshot) {
+ /* allocate spare buffer */
+ ret = resize_buffer_duplicate_size(&max_tr,
+ &global_trace, RING_BUFFER_ALL_CPUS);
+ if (ret < 0)
+ break;
+ current_trace->allocated_snapshot = true;
+ }
+
+ local_irq_disable();
+ /* Now, we're going to swap */
+ update_max_tr(&global_trace, current, smp_processor_id());
+ local_irq_enable();
+ break;
+ default:
+ if (current_trace->allocated_snapshot)
+ tracing_reset_online_cpus(&max_tr);
+ else
+ ret = -EINVAL;
+ break;
+ }
+
+ if (ret >= 0) {
+ *ppos += cnt;
+ ret = cnt;
+ }
+out:
+ mutex_unlock(&trace_types_lock);
+ return ret;
+}
+#endif /* CONFIG_TRACER_SNAPSHOT */
+
+
static const struct file_operations tracing_max_lat_fops = {
.open = tracing_open_generic,
.read = tracing_max_lat_read,
@@ -4108,6 +4216,16 @@ static const struct file_operations trace_clock_fops = {
.write = tracing_clock_write,
};
+#ifdef CONFIG_TRACER_SNAPSHOT
+static const struct file_operations snapshot_fops = {
+ .open = tracing_snapshot_open,
+ .read = seq_read,
+ .write = tracing_snapshot_write,
+ .llseek = tracing_seek,
+ .release = tracing_release,
+};
+#endif /* CONFIG_TRACER_SNAPSHOT */
+
struct ftrace_buffer_info {
struct trace_array *tr;
void *spare;
@@ -4412,6 +4530,9 @@ tracing_stats_read(struct file *filp, char __user *ubuf,
cnt = ring_buffer_dropped_events_cpu(tr->buffer, cpu);
trace_seq_printf(s, "dropped events: %ld\n", cnt);
+ cnt = ring_buffer_read_events_cpu(tr->buffer, cpu);
+ trace_seq_printf(s, "read events: %ld\n", cnt);
+
count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len);
kfree(s);
@@ -4488,7 +4609,7 @@ struct dentry *tracing_init_dentry(void)
static struct dentry *d_percpu;
-struct dentry *tracing_dentry_percpu(void)
+static struct dentry *tracing_dentry_percpu(void)
{
static int once;
struct dentry *d_tracer;
@@ -4815,10 +4936,17 @@ rb_simple_write(struct file *filp, const char __user *ubuf,
return ret;
if (buffer) {
- if (val)
+ mutex_lock(&trace_types_lock);
+ if (val) {
ring_buffer_record_on(buffer);
- else
+ if (current_trace->start)
+ current_trace->start(tr);
+ } else {
ring_buffer_record_off(buffer);
+ if (current_trace->stop)
+ current_trace->stop(tr);
+ }
+ mutex_unlock(&trace_types_lock);
}
(*ppos)++;
@@ -4897,6 +5025,11 @@ static __init int tracer_init_debugfs(void)
&ftrace_update_tot_cnt, &tracing_dyn_info_fops);
#endif
+#ifdef CONFIG_TRACER_SNAPSHOT
+ trace_create_file("snapshot", 0644, d_tracer,
+ (void *) TRACE_PIPE_ALL_CPU, &snapshot_fops);
+#endif
+
create_trace_options_dir();
for_each_tracing_cpu(cpu)
@@ -5005,6 +5138,7 @@ __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode)
if (disable_tracing)
ftrace_kill();
+ /* Simulate the iterator */
trace_init_global_iter(&iter);
for_each_tracing_cpu(cpu) {
@@ -5016,10 +5150,6 @@ __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode)
/* don't look at user memory in panic mode */
trace_flags &= ~TRACE_ITER_SYM_USEROBJ;
- /* Simulate the iterator */
- iter.tr = &global_trace;
- iter.trace = current_trace;
-
switch (oops_dump_mode) {
case DUMP_ALL:
iter.cpu_file = TRACE_PIPE_ALL_CPU;
@@ -5164,7 +5294,7 @@ __init static int tracer_alloc_buffers(void)
init_irq_work(&trace_work_wakeup, trace_wake_up);
register_tracer(&nop_trace);
- current_trace = &nop_trace;
+
/* All seems OK, enable tracing */
tracing_disabled = 0;
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index c75d7988902..57d7e5397d5 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -287,20 +287,62 @@ struct tracer {
struct tracer_flags *flags;
bool print_max;
bool use_max_tr;
+ bool allocated_snapshot;
};
/* Only current can touch trace_recursion */
-#define trace_recursion_inc() do { (current)->trace_recursion++; } while (0)
-#define trace_recursion_dec() do { (current)->trace_recursion--; } while (0)
-/* Ring buffer has the 10 LSB bits to count */
-#define trace_recursion_buffer() ((current)->trace_recursion & 0x3ff)
-
-/* for function tracing recursion */
-#define TRACE_INTERNAL_BIT (1<<11)
-#define TRACE_GLOBAL_BIT (1<<12)
-#define TRACE_CONTROL_BIT (1<<13)
+/*
+ * For function tracing recursion:
+ * The order of these bits are important.
+ *
+ * When function tracing occurs, the following steps are made:
+ * If arch does not support a ftrace feature:
+ * call internal function (uses INTERNAL bits) which calls...
+ * If callback is registered to the "global" list, the list
+ * function is called and recursion checks the GLOBAL bits.
+ * then this function calls...
+ * The function callback, which can use the FTRACE bits to
+ * check for recursion.
+ *
+ * Now if the arch does not suppport a feature, and it calls
+ * the global list function which calls the ftrace callback
+ * all three of these steps will do a recursion protection.
+ * There's no reason to do one if the previous caller already
+ * did. The recursion that we are protecting against will
+ * go through the same steps again.
+ *
+ * To prevent the multiple recursion checks, if a recursion
+ * bit is set that is higher than the MAX bit of the current
+ * check, then we know that the check was made by the previous
+ * caller, and we can skip the current check.
+ */
+enum {
+ TRACE_BUFFER_BIT,
+ TRACE_BUFFER_NMI_BIT,
+ TRACE_BUFFER_IRQ_BIT,
+ TRACE_BUFFER_SIRQ_BIT,
+
+ /* Start of function recursion bits */
+ TRACE_FTRACE_BIT,
+ TRACE_FTRACE_NMI_BIT,
+ TRACE_FTRACE_IRQ_BIT,
+ TRACE_FTRACE_SIRQ_BIT,
+
+ /* GLOBAL_BITs must be greater than FTRACE_BITs */
+ TRACE_GLOBAL_BIT,
+ TRACE_GLOBAL_NMI_BIT,
+ TRACE_GLOBAL_IRQ_BIT,
+ TRACE_GLOBAL_SIRQ_BIT,
+
+ /* INTERNAL_BITs must be greater than GLOBAL_BITs */
+ TRACE_INTERNAL_BIT,
+ TRACE_INTERNAL_NMI_BIT,
+ TRACE_INTERNAL_IRQ_BIT,
+ TRACE_INTERNAL_SIRQ_BIT,
+
+ TRACE_CONTROL_BIT,
/*
* Abuse of the trace_recursion.
@@ -309,11 +351,77 @@ struct tracer {
* was called in irq context but we have irq tracing off. Since this
* can only be modified by current, we can reuse trace_recursion.
*/
-#define TRACE_IRQ_BIT (1<<13)
+ TRACE_IRQ_BIT,
+};
+
+#define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0)
+#define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(1<<(bit)); } while (0)
+#define trace_recursion_test(bit) ((current)->trace_recursion & (1<<(bit)))
+
+#define TRACE_CONTEXT_BITS 4
+
+#define TRACE_FTRACE_START TRACE_FTRACE_BIT
+#define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1)
+
+#define TRACE_GLOBAL_START TRACE_GLOBAL_BIT
+#define TRACE_GLOBAL_MAX ((1 << (TRACE_GLOBAL_START + TRACE_CONTEXT_BITS)) - 1)
+
+#define TRACE_LIST_START TRACE_INTERNAL_BIT
+#define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)
+
+#define TRACE_CONTEXT_MASK TRACE_LIST_MAX
+
+static __always_inline int trace_get_context_bit(void)
+{
+ int bit;
-#define trace_recursion_set(bit) do { (current)->trace_recursion |= (bit); } while (0)
-#define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(bit); } while (0)
-#define trace_recursion_test(bit) ((current)->trace_recursion & (bit))
+ if (in_interrupt()) {
+ if (in_nmi())
+ bit = 0;
+
+ else if (in_irq())
+ bit = 1;
+ else
+ bit = 2;
+ } else
+ bit = 3;
+
+ return bit;
+}
+
+static __always_inline int trace_test_and_set_recursion(int start, int max)
+{
+ unsigned int val = current->trace_recursion;
+ int bit;
+
+ /* A previous recursion check was made */
+ if ((val & TRACE_CONTEXT_MASK) > max)
+ return 0;
+
+ bit = trace_get_context_bit() + start;
+ if (unlikely(val & (1 << bit)))
+ return -1;
+
+ val |= 1 << bit;
+ current->trace_recursion = val;
+ barrier();
+
+ return bit;
+}
+
+static __always_inline void trace_clear_recursion(int bit)
+{
+ unsigned int val = current->trace_recursion;
+
+ if (!bit)
+ return;
+
+ bit = 1 << bit;
+ val &= ~bit;
+
+ barrier();
+ current->trace_recursion = val;
+}
#define TRACE_PIPE_ALL_CPU -1
diff --git a/kernel/trace/trace_clock.c b/kernel/trace/trace_clock.c
index 394783531cb..aa8f5f48dae 100644
--- a/kernel/trace/trace_clock.c
+++ b/kernel/trace/trace_clock.c
@@ -21,8 +21,6 @@
#include <linux/ktime.h>
#include <linux/trace_clock.h>
-#include "trace.h"
-
/*
* trace_clock_local(): the simplest and least coherent tracing clock.
*
@@ -44,6 +42,7 @@ u64 notrace trace_clock_local(void)
return clock;
}
+EXPORT_SYMBOL_GPL(trace_clock_local);
/*
* trace_clock(): 'between' trace clock. Not completely serialized,
@@ -86,7 +85,7 @@ u64 notrace trace_clock_global(void)
local_irq_save(flags);
this_cpu = raw_smp_processor_id();
- now = cpu_clock(this_cpu);
+ now = sched_clock_cpu(this_cpu);
/*
* If in an NMI context then dont risk lockups and return the
* cpu_clock() time:
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 880073d0b94..57e9b284250 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -116,7 +116,6 @@ static int trace_define_common_fields(void)
__common_field(unsigned char, flags);
__common_field(unsigned char, preempt_count);
__common_field(int, pid);
- __common_field(int, padding);
return ret;
}
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 8e3ad8082ab..60115252332 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -47,34 +47,6 @@ static void function_trace_start(struct trace_array *tr)
tracing_reset_online_cpus(tr);
}
-static void
-function_trace_call_preempt_only(unsigned long ip, unsigned long parent_ip,
- struct ftrace_ops *op, struct pt_regs *pt_regs)
-{
- struct trace_array *tr = func_trace;
- struct trace_array_cpu *data;
- unsigned long flags;
- long disabled;
- int cpu;
- int pc;
-
- if (unlikely(!ftrace_function_enabled))
- return;
-
- pc = preempt_count();
- preempt_disable_notrace();
- local_save_flags(flags);
- cpu = raw_smp_processor_id();
- data = tr->data[cpu];
- disabled = atomic_inc_return(&data->disabled);
-
- if (likely(disabled == 1))
- trace_function(tr, ip, parent_ip, flags, pc);
-
- atomic_dec(&data->disabled);
- preempt_enable_notrace();
-}
-
/* Our option */
enum {
TRACE_FUNC_OPT_STACK = 0x1,
@@ -85,34 +57,34 @@ static struct tracer_flags func_flags;
static void
function_trace_call(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct pt_regs *pt_regs)
-
{
struct trace_array *tr = func_trace;
struct trace_array_cpu *data;
unsigned long flags;
- long disabled;
+ int bit;
int cpu;
int pc;
if (unlikely(!ftrace_function_enabled))
return;
- /*
- * Need to use raw, since this must be called before the
- * recursive protection is performed.
- */
- local_irq_save(flags);
- cpu = raw_smp_processor_id();
- data = tr->data[cpu];
- disabled = atomic_inc_return(&data->disabled);
+ pc = preempt_count();
+ preempt_disable_notrace();
- if (likely(disabled == 1)) {
- pc = preempt_count();
+ bit = trace_test_and_set_recursion(TRACE_FTRACE_START, TRACE_FTRACE_MAX);
+ if (bit < 0)
+ goto out;
+
+ cpu = smp_processor_id();
+ data = tr->data[cpu];
+ if (!atomic_read(&data->disabled)) {
+ local_save_flags(flags);
trace_function(tr, ip, parent_ip, flags, pc);
}
+ trace_clear_recursion(bit);
- atomic_dec(&data->disabled);
- local_irq_restore(flags);
+ out:
+ preempt_enable_notrace();
}
static void
@@ -185,11 +157,6 @@ static void tracing_start_function_trace(void)
{
ftrace_function_enabled = 0;
- if (trace_flags & TRACE_ITER_PREEMPTONLY)
- trace_ops.func = function_trace_call_preempt_only;
- else
- trace_ops.func = function_trace_call;
-
if (func_flags.val & TRACE_FUNC_OPT_STACK)
register_ftrace_function(&trace_stack_ops);
else
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 4edb4b74eb7..39ada66389c 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -47,6 +47,8 @@ struct fgraph_data {
#define TRACE_GRAPH_PRINT_ABS_TIME 0x20
#define TRACE_GRAPH_PRINT_IRQS 0x40
+static unsigned int max_depth;
+
static struct tracer_opt trace_opts[] = {
/* Display overruns? (for self-debug purpose) */
{ TRACER_OPT(funcgraph-overrun, TRACE_GRAPH_PRINT_OVERRUN) },
@@ -189,10 +191,16 @@ unsigned long ftrace_return_to_handler(unsigned long frame_pointer)
ftrace_pop_return_trace(&trace, &ret, frame_pointer);
trace.rettime = trace_clock_local();
- ftrace_graph_return(&trace);
barrier();
current->curr_ret_stack--;
+ /*
+ * The trace should run after decrementing the ret counter
+ * in case an interrupt were to come in. We don't want to
+ * lose the interrupt if max_depth is set.
+ */
+ ftrace_graph_return(&trace);
+
if (unlikely(!ret)) {
ftrace_graph_stop();
WARN_ON(1);
@@ -250,8 +258,9 @@ int trace_graph_entry(struct ftrace_graph_ent *trace)
return 0;
/* trace it when it is-nested-in or is a function enabled. */
- if (!(trace->depth || ftrace_graph_addr(trace->func)) ||
- ftrace_graph_ignore_irqs())
+ if ((!(trace->depth || ftrace_graph_addr(trace->func)) ||
+ ftrace_graph_ignore_irqs()) ||
+ (max_depth && trace->depth >= max_depth))
return 0;
local_irq_save(flags);
@@ -1457,6 +1466,59 @@ static struct tracer graph_trace __read_mostly = {
#endif
};
+
+static ssize_t
+graph_depth_write(struct file *filp, const char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ unsigned long val;
+ int ret;
+
+ ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
+ if (ret)
+ return ret;
+
+ max_depth = val;
+
+ *ppos += cnt;
+
+ return cnt;
+}
+
+static ssize_t
+graph_depth_read(struct file *filp, char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ char buf[15]; /* More than enough to hold UINT_MAX + "\n"*/
+ int n;
+
+ n = sprintf(buf, "%d\n", max_depth);
+
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, n);
+}
+
+static const struct file_operations graph_depth_fops = {
+ .open = tracing_open_generic,
+ .write = graph_depth_write,
+ .read = graph_depth_read,
+ .llseek = generic_file_llseek,
+};
+
+static __init int init_graph_debugfs(void)
+{
+ struct dentry *d_tracer;
+
+ d_tracer = tracing_init_dentry();
+ if (!d_tracer)
+ return 0;
+
+ trace_create_file("max_graph_depth", 0644, d_tracer,
+ NULL, &graph_depth_fops);
+
+ return 0;
+}
+fs_initcall(init_graph_debugfs);
+
static __init int init_graph_trace(void)
{
max_bytes_for_cpu = snprintf(NULL, 0, "%d", nr_cpu_ids - 1);
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 93370867781..5c7e09d10d7 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -66,7 +66,6 @@
#define TP_FLAG_TRACE 1
#define TP_FLAG_PROFILE 2
#define TP_FLAG_REGISTERED 4
-#define TP_FLAG_UPROBE 8
/* data_rloc: data relative location, compatible with u32 */
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index 9fe45fcefca..75aa97fbe1a 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -15,8 +15,8 @@
#include <linux/kallsyms.h>
#include <linux/uaccess.h>
#include <linux/ftrace.h>
+#include <linux/sched/rt.h>
#include <trace/events/sched.h>
-
#include "trace.h"
static struct trace_array *wakeup_trace;
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 47623169a81..51c819c12c2 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -415,7 +415,8 @@ static void trace_selftest_test_recursion_func(unsigned long ip,
* The ftrace infrastructure should provide the recursion
* protection. If not, this will crash the kernel!
*/
- trace_selftest_recursion_cnt++;
+ if (trace_selftest_recursion_cnt++ > 10)
+ return;
DYN_FTRACE_TEST_NAME();
}
@@ -452,7 +453,6 @@ trace_selftest_function_recursion(void)
char *func_name;
int len;
int ret;
- int cnt;
/* The previous test PASSED */
pr_cont("PASSED\n");
@@ -510,19 +510,10 @@ trace_selftest_function_recursion(void)
unregister_ftrace_function(&test_recsafe_probe);
- /*
- * If arch supports all ftrace features, and no other task
- * was on the list, we should be fine.
- */
- if (!ftrace_nr_registered_ops() && !FTRACE_FORCE_LIST_FUNC)
- cnt = 2; /* Should have recursed */
- else
- cnt = 1;
-
ret = -1;
- if (trace_selftest_recursion_cnt != cnt) {
- pr_cont("*callback not called expected %d times (%d)* ",
- cnt, trace_selftest_recursion_cnt);
+ if (trace_selftest_recursion_cnt != 2) {
+ pr_cont("*callback not called expected 2 times (%d)* ",
+ trace_selftest_recursion_cnt);
goto out;
}
@@ -568,7 +559,7 @@ trace_selftest_function_regs(void)
int ret;
int supported = 0;
-#ifdef ARCH_SUPPORTS_FTRACE_SAVE_REGS
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
supported = 1;
#endif
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 7609dd6714c..5329e13e74a 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -77,7 +77,7 @@ static struct syscall_metadata *syscall_nr_to_meta(int nr)
return syscalls_metadata[nr];
}
-enum print_line_t
+static enum print_line_t
print_syscall_enter(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
@@ -130,7 +130,7 @@ end:
return TRACE_TYPE_HANDLED;
}
-enum print_line_t
+static enum print_line_t
print_syscall_exit(struct trace_iterator *iter, int flags,
struct trace_event *event)
{
@@ -270,7 +270,7 @@ static int syscall_exit_define_fields(struct ftrace_event_call *call)
return ret;
}
-void ftrace_syscall_enter(void *ignore, struct pt_regs *regs, long id)
+static void ftrace_syscall_enter(void *ignore, struct pt_regs *regs, long id)
{
struct syscall_trace_enter *entry;
struct syscall_metadata *sys_data;
@@ -305,7 +305,7 @@ void ftrace_syscall_enter(void *ignore, struct pt_regs *regs, long id)
trace_current_buffer_unlock_commit(buffer, event, 0, 0);
}
-void ftrace_syscall_exit(void *ignore, struct pt_regs *regs, long ret)
+static void ftrace_syscall_exit(void *ignore, struct pt_regs *regs, long ret)
{
struct syscall_trace_exit *entry;
struct syscall_metadata *sys_data;
@@ -337,7 +337,7 @@ void ftrace_syscall_exit(void *ignore, struct pt_regs *regs, long ret)
trace_current_buffer_unlock_commit(buffer, event, 0, 0);
}
-int reg_event_syscall_enter(struct ftrace_event_call *call)
+static int reg_event_syscall_enter(struct ftrace_event_call *call)
{
int ret = 0;
int num;
@@ -356,7 +356,7 @@ int reg_event_syscall_enter(struct ftrace_event_call *call)
return ret;
}
-void unreg_event_syscall_enter(struct ftrace_event_call *call)
+static void unreg_event_syscall_enter(struct ftrace_event_call *call)
{
int num;
@@ -371,7 +371,7 @@ void unreg_event_syscall_enter(struct ftrace_event_call *call)
mutex_unlock(&syscall_trace_lock);
}
-int reg_event_syscall_exit(struct ftrace_event_call *call)
+static int reg_event_syscall_exit(struct ftrace_event_call *call)
{
int ret = 0;
int num;
@@ -390,7 +390,7 @@ int reg_event_syscall_exit(struct ftrace_event_call *call)
return ret;
}
-void unreg_event_syscall_exit(struct ftrace_event_call *call)
+static void unreg_event_syscall_exit(struct ftrace_event_call *call)
{
int num;
@@ -459,7 +459,7 @@ unsigned long __init __weak arch_syscall_addr(int nr)
return (unsigned long)sys_call_table[nr];
}
-int __init init_ftrace_syscalls(void)
+static int __init init_ftrace_syscalls(void)
{
struct syscall_metadata *meta;
unsigned long addr;
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index c86e6d4f67f..8dad2a92dee 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -28,20 +28,21 @@
#define UPROBE_EVENT_SYSTEM "uprobes"
+struct trace_uprobe_filter {
+ rwlock_t rwlock;
+ int nr_systemwide;
+ struct list_head perf_events;
+};
+
/*
* uprobe event core functions
*/
-struct trace_uprobe;
-struct uprobe_trace_consumer {
- struct uprobe_consumer cons;
- struct trace_uprobe *tu;
-};
-
struct trace_uprobe {
struct list_head list;
struct ftrace_event_class class;
struct ftrace_event_call call;
- struct uprobe_trace_consumer *consumer;
+ struct trace_uprobe_filter filter;
+ struct uprobe_consumer consumer;
struct inode *inode;
char *filename;
unsigned long offset;
@@ -64,6 +65,18 @@ static LIST_HEAD(uprobe_list);
static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs);
+static inline void init_trace_uprobe_filter(struct trace_uprobe_filter *filter)
+{
+ rwlock_init(&filter->rwlock);
+ filter->nr_systemwide = 0;
+ INIT_LIST_HEAD(&filter->perf_events);
+}
+
+static inline bool uprobe_filter_is_empty(struct trace_uprobe_filter *filter)
+{
+ return !filter->nr_systemwide && list_empty(&filter->perf_events);
+}
+
/*
* Allocate new trace_uprobe and initialize it (including uprobes).
*/
@@ -92,6 +105,8 @@ alloc_trace_uprobe(const char *group, const char *event, int nargs)
goto error;
INIT_LIST_HEAD(&tu->list);
+ tu->consumer.handler = uprobe_dispatcher;
+ init_trace_uprobe_filter(&tu->filter);
return tu;
error:
@@ -253,12 +268,18 @@ static int create_trace_uprobe(int argc, char **argv)
if (ret)
goto fail_address_parse;
+ inode = igrab(path.dentry->d_inode);
+ path_put(&path);
+
+ if (!inode || !S_ISREG(inode->i_mode)) {
+ ret = -EINVAL;
+ goto fail_address_parse;
+ }
+
ret = kstrtoul(arg, 0, &offset);
if (ret)
goto fail_address_parse;
- inode = igrab(path.dentry->d_inode);
-
argc -= 2;
argv += 2;
@@ -356,7 +377,7 @@ fail_address_parse:
if (inode)
iput(inode);
- pr_info("Failed to parse address.\n");
+ pr_info("Failed to parse address or file.\n");
return ret;
}
@@ -465,7 +486,7 @@ static const struct file_operations uprobe_profile_ops = {
};
/* uprobe handler */
-static void uprobe_trace_func(struct trace_uprobe *tu, struct pt_regs *regs)
+static int uprobe_trace_func(struct trace_uprobe *tu, struct pt_regs *regs)
{
struct uprobe_trace_entry_head *entry;
struct ring_buffer_event *event;
@@ -475,8 +496,6 @@ static void uprobe_trace_func(struct trace_uprobe *tu, struct pt_regs *regs)
unsigned long irq_flags;
struct ftrace_event_call *call = &tu->call;
- tu->nhit++;
-
local_save_flags(irq_flags);
pc = preempt_count();
@@ -485,16 +504,18 @@ static void uprobe_trace_func(struct trace_uprobe *tu, struct pt_regs *regs)
event = trace_current_buffer_lock_reserve(&buffer, call->event.type,
size, irq_flags, pc);
if (!event)
- return;
+ return 0;
entry = ring_buffer_event_data(event);
- entry->ip = uprobe_get_swbp_addr(task_pt_regs(current));
+ entry->ip = instruction_pointer(task_pt_regs(current));
data = (u8 *)&entry[1];
for (i = 0; i < tu->nr_args; i++)
call_fetch(&tu->args[i].fetch, regs, data + tu->args[i].offset);
if (!filter_current_check_discard(buffer, call, entry, event))
trace_buffer_unlock_commit(buffer, event, irq_flags, pc);
+
+ return 0;
}
/* Event entry printers */
@@ -533,42 +554,43 @@ partial:
return TRACE_TYPE_PARTIAL_LINE;
}
-static int probe_event_enable(struct trace_uprobe *tu, int flag)
+static inline bool is_trace_uprobe_enabled(struct trace_uprobe *tu)
{
- struct uprobe_trace_consumer *utc;
- int ret = 0;
+ return tu->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE);
+}
- if (!tu->inode || tu->consumer)
- return -EINTR;
+typedef bool (*filter_func_t)(struct uprobe_consumer *self,
+ enum uprobe_filter_ctx ctx,
+ struct mm_struct *mm);
- utc = kzalloc(sizeof(struct uprobe_trace_consumer), GFP_KERNEL);
- if (!utc)
+static int
+probe_event_enable(struct trace_uprobe *tu, int flag, filter_func_t filter)
+{
+ int ret = 0;
+
+ if (is_trace_uprobe_enabled(tu))
return -EINTR;
- utc->cons.handler = uprobe_dispatcher;
- utc->cons.filter = NULL;
- ret = uprobe_register(tu->inode, tu->offset, &utc->cons);
- if (ret) {
- kfree(utc);
- return ret;
- }
+ WARN_ON(!uprobe_filter_is_empty(&tu->filter));
tu->flags |= flag;
- utc->tu = tu;
- tu->consumer = utc;
+ tu->consumer.filter = filter;
+ ret = uprobe_register(tu->inode, tu->offset, &tu->consumer);
+ if (ret)
+ tu->flags &= ~flag;
- return 0;
+ return ret;
}
static void probe_event_disable(struct trace_uprobe *tu, int flag)
{
- if (!tu->inode || !tu->consumer)
+ if (!is_trace_uprobe_enabled(tu))
return;
- uprobe_unregister(tu->inode, tu->offset, &tu->consumer->cons);
+ WARN_ON(!uprobe_filter_is_empty(&tu->filter));
+
+ uprobe_unregister(tu->inode, tu->offset, &tu->consumer);
tu->flags &= ~flag;
- kfree(tu->consumer);
- tu->consumer = NULL;
}
static int uprobe_event_define_fields(struct ftrace_event_call *event_call)
@@ -642,8 +664,96 @@ static int set_print_fmt(struct trace_uprobe *tu)
}
#ifdef CONFIG_PERF_EVENTS
+static bool
+__uprobe_perf_filter(struct trace_uprobe_filter *filter, struct mm_struct *mm)
+{
+ struct perf_event *event;
+
+ if (filter->nr_systemwide)
+ return true;
+
+ list_for_each_entry(event, &filter->perf_events, hw.tp_list) {
+ if (event->hw.tp_target->mm == mm)
+ return true;
+ }
+
+ return false;
+}
+
+static inline bool
+uprobe_filter_event(struct trace_uprobe *tu, struct perf_event *event)
+{
+ return __uprobe_perf_filter(&tu->filter, event->hw.tp_target->mm);
+}
+
+static int uprobe_perf_open(struct trace_uprobe *tu, struct perf_event *event)
+{
+ bool done;
+
+ write_lock(&tu->filter.rwlock);
+ if (event->hw.tp_target) {
+ /*
+ * event->parent != NULL means copy_process(), we can avoid
+ * uprobe_apply(). current->mm must be probed and we can rely
+ * on dup_mmap() which preserves the already installed bp's.
+ *
+ * attr.enable_on_exec means that exec/mmap will install the
+ * breakpoints we need.
+ */
+ done = tu->filter.nr_systemwide ||
+ event->parent || event->attr.enable_on_exec ||
+ uprobe_filter_event(tu, event);
+ list_add(&event->hw.tp_list, &tu->filter.perf_events);
+ } else {
+ done = tu->filter.nr_systemwide;
+ tu->filter.nr_systemwide++;
+ }
+ write_unlock(&tu->filter.rwlock);
+
+ if (!done)
+ uprobe_apply(tu->inode, tu->offset, &tu->consumer, true);
+
+ return 0;
+}
+
+static int uprobe_perf_close(struct trace_uprobe *tu, struct perf_event *event)
+{
+ bool done;
+
+ write_lock(&tu->filter.rwlock);
+ if (event->hw.tp_target) {
+ list_del(&event->hw.tp_list);
+ done = tu->filter.nr_systemwide ||
+ (event->hw.tp_target->flags & PF_EXITING) ||
+ uprobe_filter_event(tu, event);
+ } else {
+ tu->filter.nr_systemwide--;
+ done = tu->filter.nr_systemwide;
+ }
+ write_unlock(&tu->filter.rwlock);
+
+ if (!done)
+ uprobe_apply(tu->inode, tu->offset, &tu->consumer, false);
+
+ return 0;
+}
+
+static bool uprobe_perf_filter(struct uprobe_consumer *uc,
+ enum uprobe_filter_ctx ctx, struct mm_struct *mm)
+{
+ struct trace_uprobe *tu;
+ int ret;
+
+ tu = container_of(uc, struct trace_uprobe, consumer);
+ read_lock(&tu->filter.rwlock);
+ ret = __uprobe_perf_filter(&tu->filter, mm);
+ read_unlock(&tu->filter.rwlock);
+
+ return ret;
+}
+
/* uprobe profile handler */
-static void uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs)
+static int uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs)
{
struct ftrace_event_call *call = &tu->call;
struct uprobe_trace_entry_head *entry;
@@ -652,11 +762,14 @@ static void uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs)
int size, __size, i;
int rctx;
+ if (!uprobe_perf_filter(&tu->consumer, 0, current->mm))
+ return UPROBE_HANDLER_REMOVE;
+
__size = sizeof(*entry) + tu->size;
size = ALIGN(__size + sizeof(u32), sizeof(u64));
size -= sizeof(u32);
if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, "profile buffer not large enough"))
- return;
+ return 0;
preempt_disable();
@@ -664,7 +777,7 @@ static void uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs)
if (!entry)
goto out;
- entry->ip = uprobe_get_swbp_addr(task_pt_regs(current));
+ entry->ip = instruction_pointer(task_pt_regs(current));
data = (u8 *)&entry[1];
for (i = 0; i < tu->nr_args; i++)
call_fetch(&tu->args[i].fetch, regs, data + tu->args[i].offset);
@@ -674,6 +787,7 @@ static void uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs)
out:
preempt_enable();
+ return 0;
}
#endif /* CONFIG_PERF_EVENTS */
@@ -684,7 +798,7 @@ int trace_uprobe_register(struct ftrace_event_call *event, enum trace_reg type,
switch (type) {
case TRACE_REG_REGISTER:
- return probe_event_enable(tu, TP_FLAG_TRACE);
+ return probe_event_enable(tu, TP_FLAG_TRACE, NULL);
case TRACE_REG_UNREGISTER:
probe_event_disable(tu, TP_FLAG_TRACE);
@@ -692,11 +806,18 @@ int trace_uprobe_register(struct ftrace_event_call *event, enum trace_reg type,
#ifdef CONFIG_PERF_EVENTS
case TRACE_REG_PERF_REGISTER:
- return probe_event_enable(tu, TP_FLAG_PROFILE);
+ return probe_event_enable(tu, TP_FLAG_PROFILE, uprobe_perf_filter);
case TRACE_REG_PERF_UNREGISTER:
probe_event_disable(tu, TP_FLAG_PROFILE);
return 0;
+
+ case TRACE_REG_PERF_OPEN:
+ return uprobe_perf_open(tu, data);
+
+ case TRACE_REG_PERF_CLOSE:
+ return uprobe_perf_close(tu, data);
+
#endif
default:
return 0;
@@ -706,22 +827,20 @@ int trace_uprobe_register(struct ftrace_event_call *event, enum trace_reg type,
static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs)
{
- struct uprobe_trace_consumer *utc;
struct trace_uprobe *tu;
+ int ret = 0;
- utc = container_of(con, struct uprobe_trace_consumer, cons);
- tu = utc->tu;
- if (!tu || tu->consumer != utc)
- return 0;
+ tu = container_of(con, struct trace_uprobe, consumer);
+ tu->nhit++;
if (tu->flags & TP_FLAG_TRACE)
- uprobe_trace_func(tu, regs);
+ ret |= uprobe_trace_func(tu, regs);
#ifdef CONFIG_PERF_EVENTS
if (tu->flags & TP_FLAG_PROFILE)
- uprobe_perf_func(tu, regs);
+ ret |= uprobe_perf_func(tu, regs);
#endif
- return 0;
+ return ret;
}
static struct trace_event_functions uprobe_funcs = {
diff --git a/kernel/tsacct.c b/kernel/tsacct.c
index 625df0b4469..a1dd9a1b132 100644
--- a/kernel/tsacct.c
+++ b/kernel/tsacct.c
@@ -32,6 +32,7 @@ void bacct_add_tsk(struct user_namespace *user_ns,
{
const struct cred *tcred;
struct timespec uptime, ts;
+ cputime_t utime, stime, utimescaled, stimescaled;
u64 ac_etime;
BUILD_BUG_ON(TS_COMM_LEN < TASK_COMM_LEN);
@@ -65,10 +66,15 @@ void bacct_add_tsk(struct user_namespace *user_ns,
stats->ac_ppid = pid_alive(tsk) ?
task_tgid_nr_ns(rcu_dereference(tsk->real_parent), pid_ns) : 0;
rcu_read_unlock();
- stats->ac_utime = cputime_to_usecs(tsk->utime);
- stats->ac_stime = cputime_to_usecs(tsk->stime);
- stats->ac_utimescaled = cputime_to_usecs(tsk->utimescaled);
- stats->ac_stimescaled = cputime_to_usecs(tsk->stimescaled);
+
+ task_cputime(tsk, &utime, &stime);
+ stats->ac_utime = cputime_to_usecs(utime);
+ stats->ac_stime = cputime_to_usecs(stime);
+
+ task_cputime_scaled(tsk, &utimescaled, &stimescaled);
+ stats->ac_utimescaled = cputime_to_usecs(utimescaled);
+ stats->ac_stimescaled = cputime_to_usecs(stimescaled);
+
stats->ac_minflt = tsk->min_flt;
stats->ac_majflt = tsk->maj_flt;
@@ -115,11 +121,8 @@ void xacct_add_tsk(struct taskstats *stats, struct task_struct *p)
#undef KB
#undef MB
-/**
- * acct_update_integrals - update mm integral fields in task_struct
- * @tsk: task_struct for accounting
- */
-void acct_update_integrals(struct task_struct *tsk)
+static void __acct_update_integrals(struct task_struct *tsk,
+ cputime_t utime, cputime_t stime)
{
if (likely(tsk->mm)) {
cputime_t time, dtime;
@@ -128,7 +131,7 @@ void acct_update_integrals(struct task_struct *tsk)
u64 delta;
local_irq_save(flags);
- time = tsk->stime + tsk->utime;
+ time = stime + utime;
dtime = time - tsk->acct_timexpd;
jiffies_to_timeval(cputime_to_jiffies(dtime), &value);
delta = value.tv_sec;
@@ -145,6 +148,27 @@ void acct_update_integrals(struct task_struct *tsk)
}
/**
+ * acct_update_integrals - update mm integral fields in task_struct
+ * @tsk: task_struct for accounting
+ */
+void acct_update_integrals(struct task_struct *tsk)
+{
+ cputime_t utime, stime;
+
+ task_cputime(tsk, &utime, &stime);
+ __acct_update_integrals(tsk, utime, stime);
+}
+
+/**
+ * acct_account_cputime - update mm integral after cputime update
+ * @tsk: task_struct for accounting
+ */
+void acct_account_cputime(struct task_struct *tsk)
+{
+ __acct_update_integrals(tsk, tsk->utime, tsk->stime);
+}
+
+/**
* acct_clear_integrals - clear the mm integral fields in task_struct
* @tsk: task_struct whose accounting fields are cleared
*/
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 75a2ab3d0b0..27689422aa9 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -23,6 +23,7 @@
#include <linux/module.h>
#include <linux/sysctl.h>
#include <linux/smpboot.h>
+#include <linux/sched/rt.h>
#include <asm/irq_regs.h>
#include <linux/kvm_para.h>
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index fbc6576a83c..f4feacad381 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -41,32 +41,31 @@
#include <linux/debug_locks.h>
#include <linux/lockdep.h>
#include <linux/idr.h>
+#include <linux/hashtable.h>
-#include "workqueue_sched.h"
+#include "workqueue_internal.h"
enum {
/*
- * global_cwq flags
+ * worker_pool flags
*
- * A bound gcwq is either associated or disassociated with its CPU.
+ * A bound pool is either associated or disassociated with its CPU.
* While associated (!DISASSOCIATED), all workers are bound to the
* CPU and none has %WORKER_UNBOUND set and concurrency management
* is in effect.
*
* While DISASSOCIATED, the cpu may be offline and all workers have
* %WORKER_UNBOUND set and concurrency management disabled, and may
- * be executing on any CPU. The gcwq behaves as an unbound one.
+ * be executing on any CPU. The pool behaves as an unbound one.
*
* Note that DISASSOCIATED can be flipped only while holding
- * assoc_mutex of all pools on the gcwq to avoid changing binding
- * state while create_worker() is in progress.
+ * assoc_mutex to avoid changing binding state while
+ * create_worker() is in progress.
*/
- GCWQ_DISASSOCIATED = 1 << 0, /* cpu can't serve workers */
- GCWQ_FREEZING = 1 << 1, /* freeze in progress */
-
- /* pool flags */
POOL_MANAGE_WORKERS = 1 << 0, /* need to manage workers */
POOL_MANAGING_WORKERS = 1 << 1, /* managing workers */
+ POOL_DISASSOCIATED = 1 << 2, /* cpu can't serve workers */
+ POOL_FREEZING = 1 << 3, /* freeze in progress */
/* worker flags */
WORKER_STARTED = 1 << 0, /* started */
@@ -79,11 +78,9 @@ enum {
WORKER_NOT_RUNNING = WORKER_PREP | WORKER_UNBOUND |
WORKER_CPU_INTENSIVE,
- NR_WORKER_POOLS = 2, /* # worker pools per gcwq */
+ NR_STD_WORKER_POOLS = 2, /* # standard pools per cpu */
BUSY_WORKER_HASH_ORDER = 6, /* 64 pointers */
- BUSY_WORKER_HASH_SIZE = 1 << BUSY_WORKER_HASH_ORDER,
- BUSY_WORKER_HASH_MASK = BUSY_WORKER_HASH_SIZE - 1,
MAX_IDLE_WORKERS_RATIO = 4, /* 1/4 of busy can be idle */
IDLE_WORKER_TIMEOUT = 300 * HZ, /* keep idle ones for 5 mins */
@@ -111,48 +108,24 @@ enum {
* P: Preemption protected. Disabling preemption is enough and should
* only be modified and accessed from the local cpu.
*
- * L: gcwq->lock protected. Access with gcwq->lock held.
+ * L: pool->lock protected. Access with pool->lock held.
*
- * X: During normal operation, modification requires gcwq->lock and
- * should be done only from local cpu. Either disabling preemption
- * on local cpu or grabbing gcwq->lock is enough for read access.
- * If GCWQ_DISASSOCIATED is set, it's identical to L.
+ * X: During normal operation, modification requires pool->lock and should
+ * be done only from local cpu. Either disabling preemption on local
+ * cpu or grabbing pool->lock is enough for read access. If
+ * POOL_DISASSOCIATED is set, it's identical to L.
*
* F: wq->flush_mutex protected.
*
* W: workqueue_lock protected.
*/
-struct global_cwq;
-struct worker_pool;
-
-/*
- * The poor guys doing the actual heavy lifting. All on-duty workers
- * are either serving the manager role, on idle list or on busy hash.
- */
-struct worker {
- /* on idle list while idle, on busy hash table while busy */
- union {
- struct list_head entry; /* L: while idle */
- struct hlist_node hentry; /* L: while busy */
- };
-
- struct work_struct *current_work; /* L: work being processed */
- struct cpu_workqueue_struct *current_cwq; /* L: current_work's cwq */
- struct list_head scheduled; /* L: scheduled works */
- struct task_struct *task; /* I: worker task */
- struct worker_pool *pool; /* I: the associated pool */
- /* 64 bytes boundary on 64bit, 32 on 32bit */
- unsigned long last_active; /* L: last active timestamp */
- unsigned int flags; /* X: flags */
- int id; /* I: worker id */
-
- /* for rebinding worker to CPU */
- struct work_struct rebind_work; /* L: for busy worker */
-};
+/* struct worker is defined in workqueue_internal.h */
struct worker_pool {
- struct global_cwq *gcwq; /* I: the owning gcwq */
+ spinlock_t lock; /* the pool lock */
+ unsigned int cpu; /* I: the associated cpu */
+ int id; /* I: pool ID */
unsigned int flags; /* X: flags */
struct list_head worklist; /* L: list of pending works */
@@ -165,34 +138,28 @@ struct worker_pool {
struct timer_list idle_timer; /* L: worker idle timeout */
struct timer_list mayday_timer; /* L: SOS timer for workers */
- struct mutex assoc_mutex; /* protect GCWQ_DISASSOCIATED */
- struct ida worker_ida; /* L: for worker IDs */
-};
-
-/*
- * Global per-cpu workqueue. There's one and only one for each cpu
- * and all works are queued and processed here regardless of their
- * target workqueues.
- */
-struct global_cwq {
- spinlock_t lock; /* the gcwq lock */
- unsigned int cpu; /* I: the associated cpu */
- unsigned int flags; /* L: GCWQ_* flags */
-
- /* workers are chained either in busy_hash or pool idle_list */
- struct hlist_head busy_hash[BUSY_WORKER_HASH_SIZE];
+ /* workers are chained either in busy_hash or idle_list */
+ DECLARE_HASHTABLE(busy_hash, BUSY_WORKER_HASH_ORDER);
/* L: hash of busy workers */
- struct worker_pool pools[NR_WORKER_POOLS];
- /* normal and highpri pools */
+ struct mutex assoc_mutex; /* protect POOL_DISASSOCIATED */
+ struct ida worker_ida; /* L: for worker IDs */
+
+ /*
+ * The current concurrency level. As it's likely to be accessed
+ * from other CPUs during try_to_wake_up(), put it in a separate
+ * cacheline.
+ */
+ atomic_t nr_running ____cacheline_aligned_in_smp;
} ____cacheline_aligned_in_smp;
/*
- * The per-CPU workqueue. The lower WORK_STRUCT_FLAG_BITS of
- * work_struct->data are used for flags and thus cwqs need to be
- * aligned at two's power of the number of flag bits.
+ * The per-pool workqueue. While queued, the lower WORK_STRUCT_FLAG_BITS
+ * of work_struct->data are used for flags and the remaining high bits
+ * point to the pwq; thus, pwqs need to be aligned at two's power of the
+ * number of flag bits.
*/
-struct cpu_workqueue_struct {
+struct pool_workqueue {
struct worker_pool *pool; /* I: the associated pool */
struct workqueue_struct *wq; /* I: the owning workqueue */
int work_color; /* L: current color */
@@ -241,16 +208,16 @@ typedef unsigned long mayday_mask_t;
struct workqueue_struct {
unsigned int flags; /* W: WQ_* flags */
union {
- struct cpu_workqueue_struct __percpu *pcpu;
- struct cpu_workqueue_struct *single;
+ struct pool_workqueue __percpu *pcpu;
+ struct pool_workqueue *single;
unsigned long v;
- } cpu_wq; /* I: cwq's */
+ } pool_wq; /* I: pwq's */
struct list_head list; /* W: list of all workqueues */
struct mutex flush_mutex; /* protects wq flushing */
int work_color; /* F: current work color */
int flush_color; /* F: current flush color */
- atomic_t nr_cwqs_to_flush; /* flush in progress */
+ atomic_t nr_pwqs_to_flush; /* flush in progress */
struct wq_flusher *first_flusher; /* F: first flusher */
struct list_head flusher_queue; /* F: flush waiters */
struct list_head flusher_overflow; /* F: flush overflow list */
@@ -259,7 +226,7 @@ struct workqueue_struct {
struct worker *rescuer; /* I: rescue worker */
int nr_drainers; /* W: drain in progress */
- int saved_max_active; /* W: saved cwq max_active */
+ int saved_max_active; /* W: saved pwq max_active */
#ifdef CONFIG_LOCKDEP
struct lockdep_map lockdep_map;
#endif
@@ -280,16 +247,15 @@ EXPORT_SYMBOL_GPL(system_freezable_wq);
#define CREATE_TRACE_POINTS
#include <trace/events/workqueue.h>
-#define for_each_worker_pool(pool, gcwq) \
- for ((pool) = &(gcwq)->pools[0]; \
- (pool) < &(gcwq)->pools[NR_WORKER_POOLS]; (pool)++)
+#define for_each_std_worker_pool(pool, cpu) \
+ for ((pool) = &std_worker_pools(cpu)[0]; \
+ (pool) < &std_worker_pools(cpu)[NR_STD_WORKER_POOLS]; (pool)++)
-#define for_each_busy_worker(worker, i, pos, gcwq) \
- for (i = 0; i < BUSY_WORKER_HASH_SIZE; i++) \
- hlist_for_each_entry(worker, pos, &gcwq->busy_hash[i], hentry)
+#define for_each_busy_worker(worker, i, pos, pool) \
+ hash_for_each(pool->busy_hash, i, pos, worker, hentry)
-static inline int __next_gcwq_cpu(int cpu, const struct cpumask *mask,
- unsigned int sw)
+static inline int __next_wq_cpu(int cpu, const struct cpumask *mask,
+ unsigned int sw)
{
if (cpu < nr_cpu_ids) {
if (sw & 1) {
@@ -300,42 +266,42 @@ static inline int __next_gcwq_cpu(int cpu, const struct cpumask *mask,
if (sw & 2)
return WORK_CPU_UNBOUND;
}
- return WORK_CPU_NONE;
+ return WORK_CPU_END;
}
-static inline int __next_wq_cpu(int cpu, const struct cpumask *mask,
- struct workqueue_struct *wq)
+static inline int __next_pwq_cpu(int cpu, const struct cpumask *mask,
+ struct workqueue_struct *wq)
{
- return __next_gcwq_cpu(cpu, mask, !(wq->flags & WQ_UNBOUND) ? 1 : 2);
+ return __next_wq_cpu(cpu, mask, !(wq->flags & WQ_UNBOUND) ? 1 : 2);
}
/*
* CPU iterators
*
- * An extra gcwq is defined for an invalid cpu number
+ * An extra cpu number is defined using an invalid cpu number
* (WORK_CPU_UNBOUND) to host workqueues which are not bound to any
- * specific CPU. The following iterators are similar to
- * for_each_*_cpu() iterators but also considers the unbound gcwq.
+ * specific CPU. The following iterators are similar to for_each_*_cpu()
+ * iterators but also considers the unbound CPU.
*
- * for_each_gcwq_cpu() : possible CPUs + WORK_CPU_UNBOUND
- * for_each_online_gcwq_cpu() : online CPUs + WORK_CPU_UNBOUND
- * for_each_cwq_cpu() : possible CPUs for bound workqueues,
+ * for_each_wq_cpu() : possible CPUs + WORK_CPU_UNBOUND
+ * for_each_online_wq_cpu() : online CPUs + WORK_CPU_UNBOUND
+ * for_each_pwq_cpu() : possible CPUs for bound workqueues,
* WORK_CPU_UNBOUND for unbound workqueues
*/
-#define for_each_gcwq_cpu(cpu) \
- for ((cpu) = __next_gcwq_cpu(-1, cpu_possible_mask, 3); \
- (cpu) < WORK_CPU_NONE; \
- (cpu) = __next_gcwq_cpu((cpu), cpu_possible_mask, 3))
+#define for_each_wq_cpu(cpu) \
+ for ((cpu) = __next_wq_cpu(-1, cpu_possible_mask, 3); \
+ (cpu) < WORK_CPU_END; \
+ (cpu) = __next_wq_cpu((cpu), cpu_possible_mask, 3))
-#define for_each_online_gcwq_cpu(cpu) \
- for ((cpu) = __next_gcwq_cpu(-1, cpu_online_mask, 3); \
- (cpu) < WORK_CPU_NONE; \
- (cpu) = __next_gcwq_cpu((cpu), cpu_online_mask, 3))
+#define for_each_online_wq_cpu(cpu) \
+ for ((cpu) = __next_wq_cpu(-1, cpu_online_mask, 3); \
+ (cpu) < WORK_CPU_END; \
+ (cpu) = __next_wq_cpu((cpu), cpu_online_mask, 3))
-#define for_each_cwq_cpu(cpu, wq) \
- for ((cpu) = __next_wq_cpu(-1, cpu_possible_mask, (wq)); \
- (cpu) < WORK_CPU_NONE; \
- (cpu) = __next_wq_cpu((cpu), cpu_possible_mask, (wq)))
+#define for_each_pwq_cpu(cpu, wq) \
+ for ((cpu) = __next_pwq_cpu(-1, cpu_possible_mask, (wq)); \
+ (cpu) < WORK_CPU_END; \
+ (cpu) = __next_pwq_cpu((cpu), cpu_possible_mask, (wq)))
#ifdef CONFIG_DEBUG_OBJECTS_WORK
@@ -459,57 +425,69 @@ static LIST_HEAD(workqueues);
static bool workqueue_freezing; /* W: have wqs started freezing? */
/*
- * The almighty global cpu workqueues. nr_running is the only field
- * which is expected to be used frequently by other cpus via
- * try_to_wake_up(). Put it in a separate cacheline.
+ * The CPU and unbound standard worker pools. The unbound ones have
+ * POOL_DISASSOCIATED set, and their workers have WORKER_UNBOUND set.
*/
-static DEFINE_PER_CPU(struct global_cwq, global_cwq);
-static DEFINE_PER_CPU_SHARED_ALIGNED(atomic_t, pool_nr_running[NR_WORKER_POOLS]);
+static DEFINE_PER_CPU_SHARED_ALIGNED(struct worker_pool [NR_STD_WORKER_POOLS],
+ cpu_std_worker_pools);
+static struct worker_pool unbound_std_worker_pools[NR_STD_WORKER_POOLS];
-/*
- * Global cpu workqueue and nr_running counter for unbound gcwq. The
- * gcwq is always online, has GCWQ_DISASSOCIATED set, and all its
- * workers have WORKER_UNBOUND set.
- */
-static struct global_cwq unbound_global_cwq;
-static atomic_t unbound_pool_nr_running[NR_WORKER_POOLS] = {
- [0 ... NR_WORKER_POOLS - 1] = ATOMIC_INIT(0), /* always 0 */
-};
+/* idr of all pools */
+static DEFINE_MUTEX(worker_pool_idr_mutex);
+static DEFINE_IDR(worker_pool_idr);
static int worker_thread(void *__worker);
-static int worker_pool_pri(struct worker_pool *pool)
+static struct worker_pool *std_worker_pools(int cpu)
{
- return pool - pool->gcwq->pools;
+ if (cpu != WORK_CPU_UNBOUND)
+ return per_cpu(cpu_std_worker_pools, cpu);
+ else
+ return unbound_std_worker_pools;
}
-static struct global_cwq *get_gcwq(unsigned int cpu)
+static int std_worker_pool_pri(struct worker_pool *pool)
{
- if (cpu != WORK_CPU_UNBOUND)
- return &per_cpu(global_cwq, cpu);
- else
- return &unbound_global_cwq;
+ return pool - std_worker_pools(pool->cpu);
}
-static atomic_t *get_pool_nr_running(struct worker_pool *pool)
+/* allocate ID and assign it to @pool */
+static int worker_pool_assign_id(struct worker_pool *pool)
{
- int cpu = pool->gcwq->cpu;
- int idx = worker_pool_pri(pool);
+ int ret;
- if (cpu != WORK_CPU_UNBOUND)
- return &per_cpu(pool_nr_running, cpu)[idx];
- else
- return &unbound_pool_nr_running[idx];
+ mutex_lock(&worker_pool_idr_mutex);
+ idr_pre_get(&worker_pool_idr, GFP_KERNEL);
+ ret = idr_get_new(&worker_pool_idr, pool, &pool->id);
+ mutex_unlock(&worker_pool_idr_mutex);
+
+ return ret;
}
-static struct cpu_workqueue_struct *get_cwq(unsigned int cpu,
- struct workqueue_struct *wq)
+/*
+ * Lookup worker_pool by id. The idr currently is built during boot and
+ * never modified. Don't worry about locking for now.
+ */
+static struct worker_pool *worker_pool_by_id(int pool_id)
+{
+ return idr_find(&worker_pool_idr, pool_id);
+}
+
+static struct worker_pool *get_std_worker_pool(int cpu, bool highpri)
+{
+ struct worker_pool *pools = std_worker_pools(cpu);
+
+ return &pools[highpri];
+}
+
+static struct pool_workqueue *get_pwq(unsigned int cpu,
+ struct workqueue_struct *wq)
{
if (!(wq->flags & WQ_UNBOUND)) {
if (likely(cpu < nr_cpu_ids))
- return per_cpu_ptr(wq->cpu_wq.pcpu, cpu);
+ return per_cpu_ptr(wq->pool_wq.pcpu, cpu);
} else if (likely(cpu == WORK_CPU_UNBOUND))
- return wq->cpu_wq.single;
+ return wq->pool_wq.single;
return NULL;
}
@@ -530,19 +508,19 @@ static int work_next_color(int color)
}
/*
- * While queued, %WORK_STRUCT_CWQ is set and non flag bits of a work's data
- * contain the pointer to the queued cwq. Once execution starts, the flag
- * is cleared and the high bits contain OFFQ flags and CPU number.
+ * While queued, %WORK_STRUCT_PWQ is set and non flag bits of a work's data
+ * contain the pointer to the queued pwq. Once execution starts, the flag
+ * is cleared and the high bits contain OFFQ flags and pool ID.
*
- * set_work_cwq(), set_work_cpu_and_clear_pending(), mark_work_canceling()
- * and clear_work_data() can be used to set the cwq, cpu or clear
+ * set_work_pwq(), set_work_pool_and_clear_pending(), mark_work_canceling()
+ * and clear_work_data() can be used to set the pwq, pool or clear
* work->data. These functions should only be called while the work is
* owned - ie. while the PENDING bit is set.
*
- * get_work_[g]cwq() can be used to obtain the gcwq or cwq corresponding to
- * a work. gcwq is available once the work has been queued anywhere after
- * initialization until it is sync canceled. cwq is available only while
- * the work item is queued.
+ * get_work_pool() and get_work_pwq() can be used to obtain the pool or pwq
+ * corresponding to a work. Pool is available once the work has been
+ * queued anywhere after initialization until it is sync canceled. pwq is
+ * available only while the work item is queued.
*
* %WORK_OFFQ_CANCELING is used to mark a work item which is being
* canceled. While being canceled, a work item may have its PENDING set
@@ -556,16 +534,22 @@ static inline void set_work_data(struct work_struct *work, unsigned long data,
atomic_long_set(&work->data, data | flags | work_static(work));
}
-static void set_work_cwq(struct work_struct *work,
- struct cpu_workqueue_struct *cwq,
+static void set_work_pwq(struct work_struct *work, struct pool_workqueue *pwq,
unsigned long extra_flags)
{
- set_work_data(work, (unsigned long)cwq,
- WORK_STRUCT_PENDING | WORK_STRUCT_CWQ | extra_flags);
+ set_work_data(work, (unsigned long)pwq,
+ WORK_STRUCT_PENDING | WORK_STRUCT_PWQ | extra_flags);
}
-static void set_work_cpu_and_clear_pending(struct work_struct *work,
- unsigned int cpu)
+static void set_work_pool_and_keep_pending(struct work_struct *work,
+ int pool_id)
+{
+ set_work_data(work, (unsigned long)pool_id << WORK_OFFQ_POOL_SHIFT,
+ WORK_STRUCT_PENDING);
+}
+
+static void set_work_pool_and_clear_pending(struct work_struct *work,
+ int pool_id)
{
/*
* The following wmb is paired with the implied mb in
@@ -574,67 +558,92 @@ static void set_work_cpu_and_clear_pending(struct work_struct *work,
* owner.
*/
smp_wmb();
- set_work_data(work, (unsigned long)cpu << WORK_OFFQ_CPU_SHIFT, 0);
+ set_work_data(work, (unsigned long)pool_id << WORK_OFFQ_POOL_SHIFT, 0);
}
static void clear_work_data(struct work_struct *work)
{
- smp_wmb(); /* see set_work_cpu_and_clear_pending() */
- set_work_data(work, WORK_STRUCT_NO_CPU, 0);
+ smp_wmb(); /* see set_work_pool_and_clear_pending() */
+ set_work_data(work, WORK_STRUCT_NO_POOL, 0);
}
-static struct cpu_workqueue_struct *get_work_cwq(struct work_struct *work)
+static struct pool_workqueue *get_work_pwq(struct work_struct *work)
{
unsigned long data = atomic_long_read(&work->data);
- if (data & WORK_STRUCT_CWQ)
+ if (data & WORK_STRUCT_PWQ)
return (void *)(data & WORK_STRUCT_WQ_DATA_MASK);
else
return NULL;
}
-static struct global_cwq *get_work_gcwq(struct work_struct *work)
+/**
+ * get_work_pool - return the worker_pool a given work was associated with
+ * @work: the work item of interest
+ *
+ * Return the worker_pool @work was last associated with. %NULL if none.
+ */
+static struct worker_pool *get_work_pool(struct work_struct *work)
{
unsigned long data = atomic_long_read(&work->data);
- unsigned int cpu;
+ struct worker_pool *pool;
+ int pool_id;
- if (data & WORK_STRUCT_CWQ)
- return ((struct cpu_workqueue_struct *)
- (data & WORK_STRUCT_WQ_DATA_MASK))->pool->gcwq;
+ if (data & WORK_STRUCT_PWQ)
+ return ((struct pool_workqueue *)
+ (data & WORK_STRUCT_WQ_DATA_MASK))->pool;
- cpu = data >> WORK_OFFQ_CPU_SHIFT;
- if (cpu == WORK_CPU_NONE)
+ pool_id = data >> WORK_OFFQ_POOL_SHIFT;
+ if (pool_id == WORK_OFFQ_POOL_NONE)
return NULL;
- BUG_ON(cpu >= nr_cpu_ids && cpu != WORK_CPU_UNBOUND);
- return get_gcwq(cpu);
+ pool = worker_pool_by_id(pool_id);
+ WARN_ON_ONCE(!pool);
+ return pool;
+}
+
+/**
+ * get_work_pool_id - return the worker pool ID a given work is associated with
+ * @work: the work item of interest
+ *
+ * Return the worker_pool ID @work was last associated with.
+ * %WORK_OFFQ_POOL_NONE if none.
+ */
+static int get_work_pool_id(struct work_struct *work)
+{
+ unsigned long data = atomic_long_read(&work->data);
+
+ if (data & WORK_STRUCT_PWQ)
+ return ((struct pool_workqueue *)
+ (data & WORK_STRUCT_WQ_DATA_MASK))->pool->id;
+
+ return data >> WORK_OFFQ_POOL_SHIFT;
}
static void mark_work_canceling(struct work_struct *work)
{
- struct global_cwq *gcwq = get_work_gcwq(work);
- unsigned long cpu = gcwq ? gcwq->cpu : WORK_CPU_NONE;
+ unsigned long pool_id = get_work_pool_id(work);
- set_work_data(work, (cpu << WORK_OFFQ_CPU_SHIFT) | WORK_OFFQ_CANCELING,
- WORK_STRUCT_PENDING);
+ pool_id <<= WORK_OFFQ_POOL_SHIFT;
+ set_work_data(work, pool_id | WORK_OFFQ_CANCELING, WORK_STRUCT_PENDING);
}
static bool work_is_canceling(struct work_struct *work)
{
unsigned long data = atomic_long_read(&work->data);
- return !(data & WORK_STRUCT_CWQ) && (data & WORK_OFFQ_CANCELING);
+ return !(data & WORK_STRUCT_PWQ) && (data & WORK_OFFQ_CANCELING);
}
/*
* Policy functions. These define the policies on how the global worker
* pools are managed. Unless noted otherwise, these functions assume that
- * they're being called with gcwq->lock held.
+ * they're being called with pool->lock held.
*/
static bool __need_more_worker(struct worker_pool *pool)
{
- return !atomic_read(get_pool_nr_running(pool));
+ return !atomic_read(&pool->nr_running);
}
/*
@@ -642,7 +651,7 @@ static bool __need_more_worker(struct worker_pool *pool)
* running workers.
*
* Note that, because unbound workers never contribute to nr_running, this
- * function will always return %true for unbound gcwq as long as the
+ * function will always return %true for unbound pools as long as the
* worklist isn't empty.
*/
static bool need_more_worker(struct worker_pool *pool)
@@ -659,9 +668,8 @@ static bool may_start_working(struct worker_pool *pool)
/* Do I need to keep working? Called from currently running workers. */
static bool keep_working(struct worker_pool *pool)
{
- atomic_t *nr_running = get_pool_nr_running(pool);
-
- return !list_empty(&pool->worklist) && atomic_read(nr_running) <= 1;
+ return !list_empty(&pool->worklist) &&
+ atomic_read(&pool->nr_running) <= 1;
}
/* Do we need a new worker? Called from manager. */
@@ -714,7 +722,7 @@ static struct worker *first_worker(struct worker_pool *pool)
* Wake up the first idle worker of @pool.
*
* CONTEXT:
- * spin_lock_irq(gcwq->lock).
+ * spin_lock_irq(pool->lock).
*/
static void wake_up_worker(struct worker_pool *pool)
{
@@ -740,8 +748,8 @@ void wq_worker_waking_up(struct task_struct *task, unsigned int cpu)
struct worker *worker = kthread_data(task);
if (!(worker->flags & WORKER_NOT_RUNNING)) {
- WARN_ON_ONCE(worker->pool->gcwq->cpu != cpu);
- atomic_inc(get_pool_nr_running(worker->pool));
+ WARN_ON_ONCE(worker->pool->cpu != cpu);
+ atomic_inc(&worker->pool->nr_running);
}
}
@@ -764,12 +772,18 @@ struct task_struct *wq_worker_sleeping(struct task_struct *task,
unsigned int cpu)
{
struct worker *worker = kthread_data(task), *to_wakeup = NULL;
- struct worker_pool *pool = worker->pool;
- atomic_t *nr_running = get_pool_nr_running(pool);
+ struct worker_pool *pool;
+ /*
+ * Rescuers, which may not have all the fields set up like normal
+ * workers, also reach here, let's not access anything before
+ * checking NOT_RUNNING.
+ */
if (worker->flags & WORKER_NOT_RUNNING)
return NULL;
+ pool = worker->pool;
+
/* this can only happen on the local cpu */
BUG_ON(cpu != raw_smp_processor_id());
@@ -781,10 +795,11 @@ struct task_struct *wq_worker_sleeping(struct task_struct *task,
* NOT_RUNNING is clear. This means that we're bound to and
* running on the local cpu w/ rq lock held and preemption
* disabled, which in turn means that none else could be
- * manipulating idle_list, so dereferencing idle_list without gcwq
+ * manipulating idle_list, so dereferencing idle_list without pool
* lock is safe.
*/
- if (atomic_dec_and_test(nr_running) && !list_empty(&pool->worklist))
+ if (atomic_dec_and_test(&pool->nr_running) &&
+ !list_empty(&pool->worklist))
to_wakeup = first_worker(pool);
return to_wakeup ? to_wakeup->task : NULL;
}
@@ -800,7 +815,7 @@ struct task_struct *wq_worker_sleeping(struct task_struct *task,
* woken up.
*
* CONTEXT:
- * spin_lock_irq(gcwq->lock)
+ * spin_lock_irq(pool->lock)
*/
static inline void worker_set_flags(struct worker *worker, unsigned int flags,
bool wakeup)
@@ -816,14 +831,12 @@ static inline void worker_set_flags(struct worker *worker, unsigned int flags,
*/
if ((flags & WORKER_NOT_RUNNING) &&
!(worker->flags & WORKER_NOT_RUNNING)) {
- atomic_t *nr_running = get_pool_nr_running(pool);
-
if (wakeup) {
- if (atomic_dec_and_test(nr_running) &&
+ if (atomic_dec_and_test(&pool->nr_running) &&
!list_empty(&pool->worklist))
wake_up_worker(pool);
} else
- atomic_dec(nr_running);
+ atomic_dec(&pool->nr_running);
}
worker->flags |= flags;
@@ -837,7 +850,7 @@ static inline void worker_set_flags(struct worker *worker, unsigned int flags,
* Clear @flags in @worker->flags and adjust nr_running accordingly.
*
* CONTEXT:
- * spin_lock_irq(gcwq->lock)
+ * spin_lock_irq(pool->lock)
*/
static inline void worker_clr_flags(struct worker *worker, unsigned int flags)
{
@@ -855,87 +868,56 @@ static inline void worker_clr_flags(struct worker *worker, unsigned int flags)
*/
if ((flags & WORKER_NOT_RUNNING) && (oflags & WORKER_NOT_RUNNING))
if (!(worker->flags & WORKER_NOT_RUNNING))
- atomic_inc(get_pool_nr_running(pool));
+ atomic_inc(&pool->nr_running);
}
/**
- * busy_worker_head - return the busy hash head for a work
- * @gcwq: gcwq of interest
- * @work: work to be hashed
- *
- * Return hash head of @gcwq for @work.
- *
- * CONTEXT:
- * spin_lock_irq(gcwq->lock).
- *
- * RETURNS:
- * Pointer to the hash head.
- */
-static struct hlist_head *busy_worker_head(struct global_cwq *gcwq,
- struct work_struct *work)
-{
- const int base_shift = ilog2(sizeof(struct work_struct));
- unsigned long v = (unsigned long)work;
-
- /* simple shift and fold hash, do we need something better? */
- v >>= base_shift;
- v += v >> BUSY_WORKER_HASH_ORDER;
- v &= BUSY_WORKER_HASH_MASK;
-
- return &gcwq->busy_hash[v];
-}
-
-/**
- * __find_worker_executing_work - find worker which is executing a work
- * @gcwq: gcwq of interest
- * @bwh: hash head as returned by busy_worker_head()
+ * find_worker_executing_work - find worker which is executing a work
+ * @pool: pool of interest
* @work: work to find worker for
*
- * Find a worker which is executing @work on @gcwq. @bwh should be
- * the hash head obtained by calling busy_worker_head() with the same
- * work.
+ * Find a worker which is executing @work on @pool by searching
+ * @pool->busy_hash which is keyed by the address of @work. For a worker
+ * to match, its current execution should match the address of @work and
+ * its work function. This is to avoid unwanted dependency between
+ * unrelated work executions through a work item being recycled while still
+ * being executed.
+ *
+ * This is a bit tricky. A work item may be freed once its execution
+ * starts and nothing prevents the freed area from being recycled for
+ * another work item. If the same work item address ends up being reused
+ * before the original execution finishes, workqueue will identify the
+ * recycled work item as currently executing and make it wait until the
+ * current execution finishes, introducing an unwanted dependency.
+ *
+ * This function checks the work item address, work function and workqueue
+ * to avoid false positives. Note that this isn't complete as one may
+ * construct a work function which can introduce dependency onto itself
+ * through a recycled work item. Well, if somebody wants to shoot oneself
+ * in the foot that badly, there's only so much we can do, and if such
+ * deadlock actually occurs, it should be easy to locate the culprit work
+ * function.
*
* CONTEXT:
- * spin_lock_irq(gcwq->lock).
+ * spin_lock_irq(pool->lock).
*
* RETURNS:
* Pointer to worker which is executing @work if found, NULL
* otherwise.
*/
-static struct worker *__find_worker_executing_work(struct global_cwq *gcwq,
- struct hlist_head *bwh,
- struct work_struct *work)
+static struct worker *find_worker_executing_work(struct worker_pool *pool,
+ struct work_struct *work)
{
struct worker *worker;
struct hlist_node *tmp;
- hlist_for_each_entry(worker, tmp, bwh, hentry)
- if (worker->current_work == work)
+ hash_for_each_possible(pool->busy_hash, worker, tmp, hentry,
+ (unsigned long)work)
+ if (worker->current_work == work &&
+ worker->current_func == work->func)
return worker;
- return NULL;
-}
-/**
- * find_worker_executing_work - find worker which is executing a work
- * @gcwq: gcwq of interest
- * @work: work to find worker for
- *
- * Find a worker which is executing @work on @gcwq. This function is
- * identical to __find_worker_executing_work() except that this
- * function calculates @bwh itself.
- *
- * CONTEXT:
- * spin_lock_irq(gcwq->lock).
- *
- * RETURNS:
- * Pointer to worker which is executing @work if found, NULL
- * otherwise.
- */
-static struct worker *find_worker_executing_work(struct global_cwq *gcwq,
- struct work_struct *work)
-{
- return __find_worker_executing_work(gcwq, busy_worker_head(gcwq, work),
- work);
+ return NULL;
}
/**
@@ -953,7 +935,7 @@ static struct worker *find_worker_executing_work(struct global_cwq *gcwq,
* nested inside outer list_for_each_entry_safe().
*
* CONTEXT:
- * spin_lock_irq(gcwq->lock).
+ * spin_lock_irq(pool->lock).
*/
static void move_linked_works(struct work_struct *work, struct list_head *head,
struct work_struct **nextp)
@@ -979,67 +961,67 @@ static void move_linked_works(struct work_struct *work, struct list_head *head,
*nextp = n;
}
-static void cwq_activate_delayed_work(struct work_struct *work)
+static void pwq_activate_delayed_work(struct work_struct *work)
{
- struct cpu_workqueue_struct *cwq = get_work_cwq(work);
+ struct pool_workqueue *pwq = get_work_pwq(work);
trace_workqueue_activate_work(work);
- move_linked_works(work, &cwq->pool->worklist, NULL);
+ move_linked_works(work, &pwq->pool->worklist, NULL);
__clear_bit(WORK_STRUCT_DELAYED_BIT, work_data_bits(work));
- cwq->nr_active++;
+ pwq->nr_active++;
}
-static void cwq_activate_first_delayed(struct cpu_workqueue_struct *cwq)
+static void pwq_activate_first_delayed(struct pool_workqueue *pwq)
{
- struct work_struct *work = list_first_entry(&cwq->delayed_works,
+ struct work_struct *work = list_first_entry(&pwq->delayed_works,
struct work_struct, entry);
- cwq_activate_delayed_work(work);
+ pwq_activate_delayed_work(work);
}
/**
- * cwq_dec_nr_in_flight - decrement cwq's nr_in_flight
- * @cwq: cwq of interest
+ * pwq_dec_nr_in_flight - decrement pwq's nr_in_flight
+ * @pwq: pwq of interest
* @color: color of work which left the queue
*
* A work either has completed or is removed from pending queue,
- * decrement nr_in_flight of its cwq and handle workqueue flushing.
+ * decrement nr_in_flight of its pwq and handle workqueue flushing.
*
* CONTEXT:
- * spin_lock_irq(gcwq->lock).
+ * spin_lock_irq(pool->lock).
*/
-static void cwq_dec_nr_in_flight(struct cpu_workqueue_struct *cwq, int color)
+static void pwq_dec_nr_in_flight(struct pool_workqueue *pwq, int color)
{
/* ignore uncolored works */
if (color == WORK_NO_COLOR)
return;
- cwq->nr_in_flight[color]--;
+ pwq->nr_in_flight[color]--;
- cwq->nr_active--;
- if (!list_empty(&cwq->delayed_works)) {
+ pwq->nr_active--;
+ if (!list_empty(&pwq->delayed_works)) {
/* one down, submit a delayed one */
- if (cwq->nr_active < cwq->max_active)
- cwq_activate_first_delayed(cwq);
+ if (pwq->nr_active < pwq->max_active)
+ pwq_activate_first_delayed(pwq);
}
/* is flush in progress and are we at the flushing tip? */
- if (likely(cwq->flush_color != color))
+ if (likely(pwq->flush_color != color))
return;
/* are there still in-flight works? */
- if (cwq->nr_in_flight[color])
+ if (pwq->nr_in_flight[color])
return;
- /* this cwq is done, clear flush_color */
- cwq->flush_color = -1;
+ /* this pwq is done, clear flush_color */
+ pwq->flush_color = -1;
/*
- * If this was the last cwq, wake up the first flusher. It
+ * If this was the last pwq, wake up the first flusher. It
* will handle the rest.
*/
- if (atomic_dec_and_test(&cwq->wq->nr_cwqs_to_flush))
- complete(&cwq->wq->first_flusher->done);
+ if (atomic_dec_and_test(&pwq->wq->nr_pwqs_to_flush))
+ complete(&pwq->wq->first_flusher->done);
}
/**
@@ -1070,7 +1052,8 @@ static void cwq_dec_nr_in_flight(struct cpu_workqueue_struct *cwq, int color)
static int try_to_grab_pending(struct work_struct *work, bool is_dwork,
unsigned long *flags)
{
- struct global_cwq *gcwq;
+ struct worker_pool *pool;
+ struct pool_workqueue *pwq;
local_irq_save(*flags);
@@ -1095,41 +1078,43 @@ static int try_to_grab_pending(struct work_struct *work, bool is_dwork,
* The queueing is in progress, or it is already queued. Try to
* steal it from ->worklist without clearing WORK_STRUCT_PENDING.
*/
- gcwq = get_work_gcwq(work);
- if (!gcwq)
+ pool = get_work_pool(work);
+ if (!pool)
goto fail;
- spin_lock(&gcwq->lock);
- if (!list_empty(&work->entry)) {
+ spin_lock(&pool->lock);
+ /*
+ * work->data is guaranteed to point to pwq only while the work
+ * item is queued on pwq->wq, and both updating work->data to point
+ * to pwq on queueing and to pool on dequeueing are done under
+ * pwq->pool->lock. This in turn guarantees that, if work->data
+ * points to pwq which is associated with a locked pool, the work
+ * item is currently queued on that pool.
+ */
+ pwq = get_work_pwq(work);
+ if (pwq && pwq->pool == pool) {
+ debug_work_deactivate(work);
+
/*
- * This work is queued, but perhaps we locked the wrong gcwq.
- * In that case we must see the new value after rmb(), see
- * insert_work()->wmb().
+ * A delayed work item cannot be grabbed directly because
+ * it might have linked NO_COLOR work items which, if left
+ * on the delayed_list, will confuse pwq->nr_active
+ * management later on and cause stall. Make sure the work
+ * item is activated before grabbing.
*/
- smp_rmb();
- if (gcwq == get_work_gcwq(work)) {
- debug_work_deactivate(work);
+ if (*work_data_bits(work) & WORK_STRUCT_DELAYED)
+ pwq_activate_delayed_work(work);
- /*
- * A delayed work item cannot be grabbed directly
- * because it might have linked NO_COLOR work items
- * which, if left on the delayed_list, will confuse
- * cwq->nr_active management later on and cause
- * stall. Make sure the work item is activated
- * before grabbing.
- */
- if (*work_data_bits(work) & WORK_STRUCT_DELAYED)
- cwq_activate_delayed_work(work);
+ list_del_init(&work->entry);
+ pwq_dec_nr_in_flight(get_work_pwq(work), get_work_color(work));
- list_del_init(&work->entry);
- cwq_dec_nr_in_flight(get_work_cwq(work),
- get_work_color(work));
+ /* work->data points to pwq iff queued, point to pool */
+ set_work_pool_and_keep_pending(work, pool->id);
- spin_unlock(&gcwq->lock);
- return 1;
- }
+ spin_unlock(&pool->lock);
+ return 1;
}
- spin_unlock(&gcwq->lock);
+ spin_unlock(&pool->lock);
fail:
local_irq_restore(*flags);
if (work_is_canceling(work))
@@ -1139,33 +1124,25 @@ fail:
}
/**
- * insert_work - insert a work into gcwq
- * @cwq: cwq @work belongs to
+ * insert_work - insert a work into a pool
+ * @pwq: pwq @work belongs to
* @work: work to insert
* @head: insertion point
* @extra_flags: extra WORK_STRUCT_* flags to set
*
- * Insert @work which belongs to @cwq into @gcwq after @head.
- * @extra_flags is or'd to work_struct flags.
+ * Insert @work which belongs to @pwq after @head. @extra_flags is or'd to
+ * work_struct flags.
*
* CONTEXT:
- * spin_lock_irq(gcwq->lock).
+ * spin_lock_irq(pool->lock).
*/
-static void insert_work(struct cpu_workqueue_struct *cwq,
- struct work_struct *work, struct list_head *head,
- unsigned int extra_flags)
+static void insert_work(struct pool_workqueue *pwq, struct work_struct *work,
+ struct list_head *head, unsigned int extra_flags)
{
- struct worker_pool *pool = cwq->pool;
+ struct worker_pool *pool = pwq->pool;
/* we own @work, set data and link */
- set_work_cwq(work, cwq, extra_flags);
-
- /*
- * Ensure that we get the right work->data if we see the
- * result of list_add() below, see try_to_grab_pending().
- */
- smp_wmb();
-
+ set_work_pwq(work, pwq, extra_flags);
list_add_tail(&work->entry, head);
/*
@@ -1181,41 +1158,24 @@ static void insert_work(struct cpu_workqueue_struct *cwq,
/*
* Test whether @work is being queued from another work executing on the
- * same workqueue. This is rather expensive and should only be used from
- * cold paths.
+ * same workqueue.
*/
static bool is_chained_work(struct workqueue_struct *wq)
{
- unsigned long flags;
- unsigned int cpu;
-
- for_each_gcwq_cpu(cpu) {
- struct global_cwq *gcwq = get_gcwq(cpu);
- struct worker *worker;
- struct hlist_node *pos;
- int i;
+ struct worker *worker;
- spin_lock_irqsave(&gcwq->lock, flags);
- for_each_busy_worker(worker, i, pos, gcwq) {
- if (worker->task != current)
- continue;
- spin_unlock_irqrestore(&gcwq->lock, flags);
- /*
- * I'm @worker, no locking necessary. See if @work
- * is headed to the same workqueue.
- */
- return worker->current_cwq->wq == wq;
- }
- spin_unlock_irqrestore(&gcwq->lock, flags);
- }
- return false;
+ worker = current_wq_worker();
+ /*
+ * Return %true iff I'm a worker execuing a work item on @wq. If
+ * I'm @worker, it's safe to dereference it without locking.
+ */
+ return worker && worker->current_pwq->wq == wq;
}
static void __queue_work(unsigned int cpu, struct workqueue_struct *wq,
struct work_struct *work)
{
- struct global_cwq *gcwq;
- struct cpu_workqueue_struct *cwq;
+ struct pool_workqueue *pwq;
struct list_head *worklist;
unsigned int work_flags;
unsigned int req_cpu = cpu;
@@ -1235,9 +1195,9 @@ static void __queue_work(unsigned int cpu, struct workqueue_struct *wq,
WARN_ON_ONCE(!is_chained_work(wq)))
return;
- /* determine gcwq to use */
+ /* determine the pwq to use */
if (!(wq->flags & WQ_UNBOUND)) {
- struct global_cwq *last_gcwq;
+ struct worker_pool *last_pool;
if (cpu == WORK_CPU_UNBOUND)
cpu = raw_smp_processor_id();
@@ -1248,55 +1208,54 @@ static void __queue_work(unsigned int cpu, struct workqueue_struct *wq,
* work needs to be queued on that cpu to guarantee
* non-reentrancy.
*/
- gcwq = get_gcwq(cpu);
- last_gcwq = get_work_gcwq(work);
+ pwq = get_pwq(cpu, wq);
+ last_pool = get_work_pool(work);
- if (last_gcwq && last_gcwq != gcwq) {
+ if (last_pool && last_pool != pwq->pool) {
struct worker *worker;
- spin_lock(&last_gcwq->lock);
+ spin_lock(&last_pool->lock);
- worker = find_worker_executing_work(last_gcwq, work);
+ worker = find_worker_executing_work(last_pool, work);
- if (worker && worker->current_cwq->wq == wq)
- gcwq = last_gcwq;
- else {
+ if (worker && worker->current_pwq->wq == wq) {
+ pwq = get_pwq(last_pool->cpu, wq);
+ } else {
/* meh... not running there, queue here */
- spin_unlock(&last_gcwq->lock);
- spin_lock(&gcwq->lock);
+ spin_unlock(&last_pool->lock);
+ spin_lock(&pwq->pool->lock);
}
} else {
- spin_lock(&gcwq->lock);
+ spin_lock(&pwq->pool->lock);
}
} else {
- gcwq = get_gcwq(WORK_CPU_UNBOUND);
- spin_lock(&gcwq->lock);
+ pwq = get_pwq(WORK_CPU_UNBOUND, wq);
+ spin_lock(&pwq->pool->lock);
}
- /* gcwq determined, get cwq and queue */
- cwq = get_cwq(gcwq->cpu, wq);
- trace_workqueue_queue_work(req_cpu, cwq, work);
+ /* pwq determined, queue */
+ trace_workqueue_queue_work(req_cpu, pwq, work);
if (WARN_ON(!list_empty(&work->entry))) {
- spin_unlock(&gcwq->lock);
+ spin_unlock(&pwq->pool->lock);
return;
}
- cwq->nr_in_flight[cwq->work_color]++;
- work_flags = work_color_to_flags(cwq->work_color);
+ pwq->nr_in_flight[pwq->work_color]++;
+ work_flags = work_color_to_flags(pwq->work_color);
- if (likely(cwq->nr_active < cwq->max_active)) {
+ if (likely(pwq->nr_active < pwq->max_active)) {
trace_workqueue_activate_work(work);
- cwq->nr_active++;
- worklist = &cwq->pool->worklist;
+ pwq->nr_active++;
+ worklist = &pwq->pool->worklist;
} else {
work_flags |= WORK_STRUCT_DELAYED;
- worklist = &cwq->delayed_works;
+ worklist = &pwq->delayed_works;
}
- insert_work(cwq, work, worklist, work_flags);
+ insert_work(pwq, work, worklist, work_flags);
- spin_unlock(&gcwq->lock);
+ spin_unlock(&pwq->pool->lock);
}
/**
@@ -1347,19 +1306,17 @@ EXPORT_SYMBOL_GPL(queue_work);
void delayed_work_timer_fn(unsigned long __data)
{
struct delayed_work *dwork = (struct delayed_work *)__data;
- struct cpu_workqueue_struct *cwq = get_work_cwq(&dwork->work);
/* should have been called from irqsafe timer with irq already off */
- __queue_work(dwork->cpu, cwq->wq, &dwork->work);
+ __queue_work(dwork->cpu, dwork->wq, &dwork->work);
}
-EXPORT_SYMBOL_GPL(delayed_work_timer_fn);
+EXPORT_SYMBOL(delayed_work_timer_fn);
static void __queue_delayed_work(int cpu, struct workqueue_struct *wq,
struct delayed_work *dwork, unsigned long delay)
{
struct timer_list *timer = &dwork->timer;
struct work_struct *work = &dwork->work;
- unsigned int lcpu;
WARN_ON_ONCE(timer->function != delayed_work_timer_fn ||
timer->data != (unsigned long)dwork);
@@ -1379,30 +1336,7 @@ static void __queue_delayed_work(int cpu, struct workqueue_struct *wq,
timer_stats_timer_set_start_info(&dwork->timer);
- /*
- * This stores cwq for the moment, for the timer_fn. Note that the
- * work's gcwq is preserved to allow reentrance detection for
- * delayed works.
- */
- if (!(wq->flags & WQ_UNBOUND)) {
- struct global_cwq *gcwq = get_work_gcwq(work);
-
- /*
- * If we cannot get the last gcwq from @work directly,
- * select the last CPU such that it avoids unnecessarily
- * triggering non-reentrancy check in __queue_work().
- */
- lcpu = cpu;
- if (gcwq)
- lcpu = gcwq->cpu;
- if (lcpu == WORK_CPU_UNBOUND)
- lcpu = raw_smp_processor_id();
- } else {
- lcpu = WORK_CPU_UNBOUND;
- }
-
- set_work_cwq(work, get_cwq(lcpu, wq), 0);
-
+ dwork->wq = wq;
dwork->cpu = cpu;
timer->expires = jiffies + delay;
@@ -1519,12 +1453,11 @@ EXPORT_SYMBOL_GPL(mod_delayed_work);
* necessary.
*
* LOCKING:
- * spin_lock_irq(gcwq->lock).
+ * spin_lock_irq(pool->lock).
*/
static void worker_enter_idle(struct worker *worker)
{
struct worker_pool *pool = worker->pool;
- struct global_cwq *gcwq = pool->gcwq;
BUG_ON(worker->flags & WORKER_IDLE);
BUG_ON(!list_empty(&worker->entry) &&
@@ -1542,14 +1475,14 @@ static void worker_enter_idle(struct worker *worker)
mod_timer(&pool->idle_timer, jiffies + IDLE_WORKER_TIMEOUT);
/*
- * Sanity check nr_running. Because gcwq_unbind_fn() releases
- * gcwq->lock between setting %WORKER_UNBOUND and zapping
+ * Sanity check nr_running. Because wq_unbind_fn() releases
+ * pool->lock between setting %WORKER_UNBOUND and zapping
* nr_running, the warning may trigger spuriously. Check iff
* unbind is not in progress.
*/
- WARN_ON_ONCE(!(gcwq->flags & GCWQ_DISASSOCIATED) &&
+ WARN_ON_ONCE(!(pool->flags & POOL_DISASSOCIATED) &&
pool->nr_workers == pool->nr_idle &&
- atomic_read(get_pool_nr_running(pool)));
+ atomic_read(&pool->nr_running));
}
/**
@@ -1559,7 +1492,7 @@ static void worker_enter_idle(struct worker *worker)
* @worker is leaving idle state. Update stats.
*
* LOCKING:
- * spin_lock_irq(gcwq->lock).
+ * spin_lock_irq(pool->lock).
*/
static void worker_leave_idle(struct worker *worker)
{
@@ -1572,7 +1505,7 @@ static void worker_leave_idle(struct worker *worker)
}
/**
- * worker_maybe_bind_and_lock - bind worker to its cpu if possible and lock gcwq
+ * worker_maybe_bind_and_lock - bind worker to its cpu if possible and lock pool
* @worker: self
*
* Works which are scheduled while the cpu is online must at least be
@@ -1584,27 +1517,27 @@ static void worker_leave_idle(struct worker *worker)
* themselves to the target cpu and may race with cpu going down or
* coming online. kthread_bind() can't be used because it may put the
* worker to already dead cpu and set_cpus_allowed_ptr() can't be used
- * verbatim as it's best effort and blocking and gcwq may be
+ * verbatim as it's best effort and blocking and pool may be
* [dis]associated in the meantime.
*
- * This function tries set_cpus_allowed() and locks gcwq and verifies the
- * binding against %GCWQ_DISASSOCIATED which is set during
+ * This function tries set_cpus_allowed() and locks pool and verifies the
+ * binding against %POOL_DISASSOCIATED which is set during
* %CPU_DOWN_PREPARE and cleared during %CPU_ONLINE, so if the worker
* enters idle state or fetches works without dropping lock, it can
* guarantee the scheduling requirement described in the first paragraph.
*
* CONTEXT:
- * Might sleep. Called without any lock but returns with gcwq->lock
+ * Might sleep. Called without any lock but returns with pool->lock
* held.
*
* RETURNS:
- * %true if the associated gcwq is online (@worker is successfully
+ * %true if the associated pool is online (@worker is successfully
* bound), %false if offline.
*/
static bool worker_maybe_bind_and_lock(struct worker *worker)
-__acquires(&gcwq->lock)
+__acquires(&pool->lock)
{
- struct global_cwq *gcwq = worker->pool->gcwq;
+ struct worker_pool *pool = worker->pool;
struct task_struct *task = worker->task;
while (true) {
@@ -1612,19 +1545,19 @@ __acquires(&gcwq->lock)
* The following call may fail, succeed or succeed
* without actually migrating the task to the cpu if
* it races with cpu hotunplug operation. Verify
- * against GCWQ_DISASSOCIATED.
+ * against POOL_DISASSOCIATED.
*/
- if (!(gcwq->flags & GCWQ_DISASSOCIATED))
- set_cpus_allowed_ptr(task, get_cpu_mask(gcwq->cpu));
+ if (!(pool->flags & POOL_DISASSOCIATED))
+ set_cpus_allowed_ptr(task, get_cpu_mask(pool->cpu));
- spin_lock_irq(&gcwq->lock);
- if (gcwq->flags & GCWQ_DISASSOCIATED)
+ spin_lock_irq(&pool->lock);
+ if (pool->flags & POOL_DISASSOCIATED)
return false;
- if (task_cpu(task) == gcwq->cpu &&
+ if (task_cpu(task) == pool->cpu &&
cpumask_equal(&current->cpus_allowed,
- get_cpu_mask(gcwq->cpu)))
+ get_cpu_mask(pool->cpu)))
return true;
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&pool->lock);
/*
* We've raced with CPU hot[un]plug. Give it a breather
@@ -1643,15 +1576,13 @@ __acquires(&gcwq->lock)
*/
static void idle_worker_rebind(struct worker *worker)
{
- struct global_cwq *gcwq = worker->pool->gcwq;
-
/* CPU may go down again inbetween, clear UNBOUND only on success */
if (worker_maybe_bind_and_lock(worker))
worker_clr_flags(worker, WORKER_UNBOUND);
/* rebind complete, become available again */
list_add(&worker->entry, &worker->pool->idle_list);
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&worker->pool->lock);
}
/*
@@ -1663,19 +1594,18 @@ static void idle_worker_rebind(struct worker *worker)
static void busy_worker_rebind_fn(struct work_struct *work)
{
struct worker *worker = container_of(work, struct worker, rebind_work);
- struct global_cwq *gcwq = worker->pool->gcwq;
if (worker_maybe_bind_and_lock(worker))
worker_clr_flags(worker, WORKER_UNBOUND);
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&worker->pool->lock);
}
/**
- * rebind_workers - rebind all workers of a gcwq to the associated CPU
- * @gcwq: gcwq of interest
+ * rebind_workers - rebind all workers of a pool to the associated CPU
+ * @pool: pool of interest
*
- * @gcwq->cpu is coming online. Rebind all workers to the CPU. Rebinding
+ * @pool->cpu is coming online. Rebind all workers to the CPU. Rebinding
* is different for idle and busy ones.
*
* Idle ones will be removed from the idle_list and woken up. They will
@@ -1693,38 +1623,32 @@ static void busy_worker_rebind_fn(struct work_struct *work)
* including the manager will not appear on @idle_list until rebind is
* complete, making local wake-ups safe.
*/
-static void rebind_workers(struct global_cwq *gcwq)
+static void rebind_workers(struct worker_pool *pool)
{
- struct worker_pool *pool;
struct worker *worker, *n;
struct hlist_node *pos;
int i;
- lockdep_assert_held(&gcwq->lock);
-
- for_each_worker_pool(pool, gcwq)
- lockdep_assert_held(&pool->assoc_mutex);
+ lockdep_assert_held(&pool->assoc_mutex);
+ lockdep_assert_held(&pool->lock);
/* dequeue and kick idle ones */
- for_each_worker_pool(pool, gcwq) {
- list_for_each_entry_safe(worker, n, &pool->idle_list, entry) {
- /*
- * idle workers should be off @pool->idle_list
- * until rebind is complete to avoid receiving
- * premature local wake-ups.
- */
- list_del_init(&worker->entry);
+ list_for_each_entry_safe(worker, n, &pool->idle_list, entry) {
+ /*
+ * idle workers should be off @pool->idle_list until rebind
+ * is complete to avoid receiving premature local wake-ups.
+ */
+ list_del_init(&worker->entry);
- /*
- * worker_thread() will see the above dequeuing
- * and call idle_worker_rebind().
- */
- wake_up_process(worker->task);
- }
+ /*
+ * worker_thread() will see the above dequeuing and call
+ * idle_worker_rebind().
+ */
+ wake_up_process(worker->task);
}
/* rebind busy workers */
- for_each_busy_worker(worker, i, pos, gcwq) {
+ for_each_busy_worker(worker, i, pos, pool) {
struct work_struct *rebind_work = &worker->rebind_work;
struct workqueue_struct *wq;
@@ -1736,16 +1660,16 @@ static void rebind_workers(struct global_cwq *gcwq)
/*
* wq doesn't really matter but let's keep @worker->pool
- * and @cwq->pool consistent for sanity.
+ * and @pwq->pool consistent for sanity.
*/
- if (worker_pool_pri(worker->pool))
+ if (std_worker_pool_pri(worker->pool))
wq = system_highpri_wq;
else
wq = system_wq;
- insert_work(get_cwq(gcwq->cpu, wq), rebind_work,
- worker->scheduled.next,
- work_color_to_flags(WORK_NO_COLOR));
+ insert_work(get_pwq(pool->cpu, wq), rebind_work,
+ worker->scheduled.next,
+ work_color_to_flags(WORK_NO_COLOR));
}
}
@@ -1780,19 +1704,18 @@ static struct worker *alloc_worker(void)
*/
static struct worker *create_worker(struct worker_pool *pool)
{
- struct global_cwq *gcwq = pool->gcwq;
- const char *pri = worker_pool_pri(pool) ? "H" : "";
+ const char *pri = std_worker_pool_pri(pool) ? "H" : "";
struct worker *worker = NULL;
int id = -1;
- spin_lock_irq(&gcwq->lock);
+ spin_lock_irq(&pool->lock);
while (ida_get_new(&pool->worker_ida, &id)) {
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&pool->lock);
if (!ida_pre_get(&pool->worker_ida, GFP_KERNEL))
goto fail;
- spin_lock_irq(&gcwq->lock);
+ spin_lock_irq(&pool->lock);
}
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&pool->lock);
worker = alloc_worker();
if (!worker)
@@ -1801,30 +1724,30 @@ static struct worker *create_worker(struct worker_pool *pool)
worker->pool = pool;
worker->id = id;
- if (gcwq->cpu != WORK_CPU_UNBOUND)
+ if (pool->cpu != WORK_CPU_UNBOUND)
worker->task = kthread_create_on_node(worker_thread,
- worker, cpu_to_node(gcwq->cpu),
- "kworker/%u:%d%s", gcwq->cpu, id, pri);
+ worker, cpu_to_node(pool->cpu),
+ "kworker/%u:%d%s", pool->cpu, id, pri);
else
worker->task = kthread_create(worker_thread, worker,
"kworker/u:%d%s", id, pri);
if (IS_ERR(worker->task))
goto fail;
- if (worker_pool_pri(pool))
+ if (std_worker_pool_pri(pool))
set_user_nice(worker->task, HIGHPRI_NICE_LEVEL);
/*
* Determine CPU binding of the new worker depending on
- * %GCWQ_DISASSOCIATED. The caller is responsible for ensuring the
+ * %POOL_DISASSOCIATED. The caller is responsible for ensuring the
* flag remains stable across this function. See the comments
* above the flag definition for details.
*
* As an unbound worker may later become a regular one if CPU comes
* online, make sure every worker has %PF_THREAD_BOUND set.
*/
- if (!(gcwq->flags & GCWQ_DISASSOCIATED)) {
- kthread_bind(worker->task, gcwq->cpu);
+ if (!(pool->flags & POOL_DISASSOCIATED)) {
+ kthread_bind(worker->task, pool->cpu);
} else {
worker->task->flags |= PF_THREAD_BOUND;
worker->flags |= WORKER_UNBOUND;
@@ -1833,9 +1756,9 @@ static struct worker *create_worker(struct worker_pool *pool)
return worker;
fail:
if (id >= 0) {
- spin_lock_irq(&gcwq->lock);
+ spin_lock_irq(&pool->lock);
ida_remove(&pool->worker_ida, id);
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&pool->lock);
}
kfree(worker);
return NULL;
@@ -1845,10 +1768,10 @@ fail:
* start_worker - start a newly created worker
* @worker: worker to start
*
- * Make the gcwq aware of @worker and start it.
+ * Make the pool aware of @worker and start it.
*
* CONTEXT:
- * spin_lock_irq(gcwq->lock).
+ * spin_lock_irq(pool->lock).
*/
static void start_worker(struct worker *worker)
{
@@ -1862,15 +1785,14 @@ static void start_worker(struct worker *worker)
* destroy_worker - destroy a workqueue worker
* @worker: worker to be destroyed
*
- * Destroy @worker and adjust @gcwq stats accordingly.
+ * Destroy @worker and adjust @pool stats accordingly.
*
* CONTEXT:
- * spin_lock_irq(gcwq->lock) which is released and regrabbed.
+ * spin_lock_irq(pool->lock) which is released and regrabbed.
*/
static void destroy_worker(struct worker *worker)
{
struct worker_pool *pool = worker->pool;
- struct global_cwq *gcwq = pool->gcwq;
int id = worker->id;
/* sanity check frenzy */
@@ -1885,21 +1807,20 @@ static void destroy_worker(struct worker *worker)
list_del_init(&worker->entry);
worker->flags |= WORKER_DIE;
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&pool->lock);
kthread_stop(worker->task);
kfree(worker);
- spin_lock_irq(&gcwq->lock);
+ spin_lock_irq(&pool->lock);
ida_remove(&pool->worker_ida, id);
}
static void idle_worker_timeout(unsigned long __pool)
{
struct worker_pool *pool = (void *)__pool;
- struct global_cwq *gcwq = pool->gcwq;
- spin_lock_irq(&gcwq->lock);
+ spin_lock_irq(&pool->lock);
if (too_many_workers(pool)) {
struct worker *worker;
@@ -1918,20 +1839,20 @@ static void idle_worker_timeout(unsigned long __pool)
}
}
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&pool->lock);
}
static bool send_mayday(struct work_struct *work)
{
- struct cpu_workqueue_struct *cwq = get_work_cwq(work);
- struct workqueue_struct *wq = cwq->wq;
+ struct pool_workqueue *pwq = get_work_pwq(work);
+ struct workqueue_struct *wq = pwq->wq;
unsigned int cpu;
if (!(wq->flags & WQ_RESCUER))
return false;
/* mayday mayday mayday */
- cpu = cwq->pool->gcwq->cpu;
+ cpu = pwq->pool->cpu;
/* WORK_CPU_UNBOUND can't be set in cpumask, use cpu 0 instead */
if (cpu == WORK_CPU_UNBOUND)
cpu = 0;
@@ -1940,13 +1861,12 @@ static bool send_mayday(struct work_struct *work)
return true;
}
-static void gcwq_mayday_timeout(unsigned long __pool)
+static void pool_mayday_timeout(unsigned long __pool)
{
struct worker_pool *pool = (void *)__pool;
- struct global_cwq *gcwq = pool->gcwq;
struct work_struct *work;
- spin_lock_irq(&gcwq->lock);
+ spin_lock_irq(&pool->lock);
if (need_to_create_worker(pool)) {
/*
@@ -1959,7 +1879,7 @@ static void gcwq_mayday_timeout(unsigned long __pool)
send_mayday(work);
}
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&pool->lock);
mod_timer(&pool->mayday_timer, jiffies + MAYDAY_INTERVAL);
}
@@ -1978,24 +1898,22 @@ static void gcwq_mayday_timeout(unsigned long __pool)
* may_start_working() true.
*
* LOCKING:
- * spin_lock_irq(gcwq->lock) which may be released and regrabbed
+ * spin_lock_irq(pool->lock) which may be released and regrabbed
* multiple times. Does GFP_KERNEL allocations. Called only from
* manager.
*
* RETURNS:
- * false if no action was taken and gcwq->lock stayed locked, true
+ * false if no action was taken and pool->lock stayed locked, true
* otherwise.
*/
static bool maybe_create_worker(struct worker_pool *pool)
-__releases(&gcwq->lock)
-__acquires(&gcwq->lock)
+__releases(&pool->lock)
+__acquires(&pool->lock)
{
- struct global_cwq *gcwq = pool->gcwq;
-
if (!need_to_create_worker(pool))
return false;
restart:
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&pool->lock);
/* if we don't make progress in MAYDAY_INITIAL_TIMEOUT, call for help */
mod_timer(&pool->mayday_timer, jiffies + MAYDAY_INITIAL_TIMEOUT);
@@ -2006,7 +1924,7 @@ restart:
worker = create_worker(pool);
if (worker) {
del_timer_sync(&pool->mayday_timer);
- spin_lock_irq(&gcwq->lock);
+ spin_lock_irq(&pool->lock);
start_worker(worker);
BUG_ON(need_to_create_worker(pool));
return true;
@@ -2023,7 +1941,7 @@ restart:
}
del_timer_sync(&pool->mayday_timer);
- spin_lock_irq(&gcwq->lock);
+ spin_lock_irq(&pool->lock);
if (need_to_create_worker(pool))
goto restart;
return true;
@@ -2037,11 +1955,11 @@ restart:
* IDLE_WORKER_TIMEOUT.
*
* LOCKING:
- * spin_lock_irq(gcwq->lock) which may be released and regrabbed
+ * spin_lock_irq(pool->lock) which may be released and regrabbed
* multiple times. Called only from manager.
*
* RETURNS:
- * false if no action was taken and gcwq->lock stayed locked, true
+ * false if no action was taken and pool->lock stayed locked, true
* otherwise.
*/
static bool maybe_destroy_workers(struct worker_pool *pool)
@@ -2071,21 +1989,21 @@ static bool maybe_destroy_workers(struct worker_pool *pool)
* manage_workers - manage worker pool
* @worker: self
*
- * Assume the manager role and manage gcwq worker pool @worker belongs
+ * Assume the manager role and manage the worker pool @worker belongs
* to. At any given time, there can be only zero or one manager per
- * gcwq. The exclusion is handled automatically by this function.
+ * pool. The exclusion is handled automatically by this function.
*
* The caller can safely start processing works on false return. On
* true return, it's guaranteed that need_to_create_worker() is false
* and may_start_working() is true.
*
* CONTEXT:
- * spin_lock_irq(gcwq->lock) which may be released and regrabbed
+ * spin_lock_irq(pool->lock) which may be released and regrabbed
* multiple times. Does GFP_KERNEL allocations.
*
* RETURNS:
- * false if no action was taken and gcwq->lock stayed locked, true if
- * some action was taken.
+ * spin_lock_irq(pool->lock) which may be released and regrabbed
+ * multiple times. Does GFP_KERNEL allocations.
*/
static bool manage_workers(struct worker *worker)
{
@@ -2107,20 +2025,20 @@ static bool manage_workers(struct worker *worker)
* manager against CPU hotplug.
*
* assoc_mutex would always be free unless CPU hotplug is in
- * progress. trylock first without dropping @gcwq->lock.
+ * progress. trylock first without dropping @pool->lock.
*/
if (unlikely(!mutex_trylock(&pool->assoc_mutex))) {
- spin_unlock_irq(&pool->gcwq->lock);
+ spin_unlock_irq(&pool->lock);
mutex_lock(&pool->assoc_mutex);
/*
* CPU hotplug could have happened while we were waiting
* for assoc_mutex. Hotplug itself can't handle us
* because manager isn't either on idle or busy list, and
- * @gcwq's state and ours could have deviated.
+ * @pool's state and ours could have deviated.
*
* As hotplug is now excluded via assoc_mutex, we can
* simply try to bind. It will succeed or fail depending
- * on @gcwq's current state. Try it and adjust
+ * on @pool's current state. Try it and adjust
* %WORKER_UNBOUND accordingly.
*/
if (worker_maybe_bind_and_lock(worker))
@@ -2157,18 +2075,15 @@ static bool manage_workers(struct worker *worker)
* call this function to process a work.
*
* CONTEXT:
- * spin_lock_irq(gcwq->lock) which is released and regrabbed.
+ * spin_lock_irq(pool->lock) which is released and regrabbed.
*/
static void process_one_work(struct worker *worker, struct work_struct *work)
-__releases(&gcwq->lock)
-__acquires(&gcwq->lock)
+__releases(&pool->lock)
+__acquires(&pool->lock)
{
- struct cpu_workqueue_struct *cwq = get_work_cwq(work);
+ struct pool_workqueue *pwq = get_work_pwq(work);
struct worker_pool *pool = worker->pool;
- struct global_cwq *gcwq = pool->gcwq;
- struct hlist_head *bwh = busy_worker_head(gcwq, work);
- bool cpu_intensive = cwq->wq->flags & WQ_CPU_INTENSIVE;
- work_func_t f = work->func;
+ bool cpu_intensive = pwq->wq->flags & WQ_CPU_INTENSIVE;
int work_color;
struct worker *collision;
#ifdef CONFIG_LOCKDEP
@@ -2186,11 +2101,11 @@ __acquires(&gcwq->lock)
/*
* Ensure we're on the correct CPU. DISASSOCIATED test is
* necessary to avoid spurious warnings from rescuers servicing the
- * unbound or a disassociated gcwq.
+ * unbound or a disassociated pool.
*/
WARN_ON_ONCE(!(worker->flags & WORKER_UNBOUND) &&
- !(gcwq->flags & GCWQ_DISASSOCIATED) &&
- raw_smp_processor_id() != gcwq->cpu);
+ !(pool->flags & POOL_DISASSOCIATED) &&
+ raw_smp_processor_id() != pool->cpu);
/*
* A single work shouldn't be executed concurrently by
@@ -2198,7 +2113,7 @@ __acquires(&gcwq->lock)
* already processing the work. If so, defer the work to the
* currently executing one.
*/
- collision = __find_worker_executing_work(gcwq, bwh, work);
+ collision = find_worker_executing_work(pool, work);
if (unlikely(collision)) {
move_linked_works(work, &collision->scheduled, NULL);
return;
@@ -2206,9 +2121,10 @@ __acquires(&gcwq->lock)
/* claim and dequeue */
debug_work_deactivate(work);
- hlist_add_head(&worker->hentry, bwh);
+ hash_add(pool->busy_hash, &worker->hentry, (unsigned long)work);
worker->current_work = work;
- worker->current_cwq = cwq;
+ worker->current_func = work->func;
+ worker->current_pwq = pwq;
work_color = get_work_color(work);
list_del_init(&work->entry);
@@ -2221,53 +2137,55 @@ __acquires(&gcwq->lock)
worker_set_flags(worker, WORKER_CPU_INTENSIVE, true);
/*
- * Unbound gcwq isn't concurrency managed and work items should be
+ * Unbound pool isn't concurrency managed and work items should be
* executed ASAP. Wake up another worker if necessary.
*/
if ((worker->flags & WORKER_UNBOUND) && need_more_worker(pool))
wake_up_worker(pool);
/*
- * Record the last CPU and clear PENDING which should be the last
- * update to @work. Also, do this inside @gcwq->lock so that
+ * Record the last pool and clear PENDING which should be the last
+ * update to @work. Also, do this inside @pool->lock so that
* PENDING and queued state changes happen together while IRQ is
* disabled.
*/
- set_work_cpu_and_clear_pending(work, gcwq->cpu);
+ set_work_pool_and_clear_pending(work, pool->id);
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&pool->lock);
- lock_map_acquire_read(&cwq->wq->lockdep_map);
+ lock_map_acquire_read(&pwq->wq->lockdep_map);
lock_map_acquire(&lockdep_map);
trace_workqueue_execute_start(work);
- f(work);
+ worker->current_func(work);
/*
* While we must be careful to not use "work" after this, the trace
* point will only record its address.
*/
trace_workqueue_execute_end(work);
lock_map_release(&lockdep_map);
- lock_map_release(&cwq->wq->lockdep_map);
+ lock_map_release(&pwq->wq->lockdep_map);
if (unlikely(in_atomic() || lockdep_depth(current) > 0)) {
pr_err("BUG: workqueue leaked lock or atomic: %s/0x%08x/%d\n"
" last function: %pf\n",
- current->comm, preempt_count(), task_pid_nr(current), f);
+ current->comm, preempt_count(), task_pid_nr(current),
+ worker->current_func);
debug_show_held_locks(current);
dump_stack();
}
- spin_lock_irq(&gcwq->lock);
+ spin_lock_irq(&pool->lock);
/* clear cpu intensive status */
if (unlikely(cpu_intensive))
worker_clr_flags(worker, WORKER_CPU_INTENSIVE);
/* we're done with it, release */
- hlist_del_init(&worker->hentry);
+ hash_del(&worker->hentry);
worker->current_work = NULL;
- worker->current_cwq = NULL;
- cwq_dec_nr_in_flight(cwq, work_color);
+ worker->current_func = NULL;
+ worker->current_pwq = NULL;
+ pwq_dec_nr_in_flight(pwq, work_color);
}
/**
@@ -2279,7 +2197,7 @@ __acquires(&gcwq->lock)
* fetches a work from the top and executes it.
*
* CONTEXT:
- * spin_lock_irq(gcwq->lock) which may be released and regrabbed
+ * spin_lock_irq(pool->lock) which may be released and regrabbed
* multiple times.
*/
static void process_scheduled_works(struct worker *worker)
@@ -2295,8 +2213,8 @@ static void process_scheduled_works(struct worker *worker)
* worker_thread - the worker thread function
* @__worker: self
*
- * The gcwq worker thread function. There's a single dynamic pool of
- * these per each cpu. These workers process all works regardless of
+ * The worker thread function. There are NR_CPU_WORKER_POOLS dynamic pools
+ * of these per each cpu. These workers process all works regardless of
* their specific target workqueue. The only exception is works which
* belong to workqueues with a rescuer which will be explained in
* rescuer_thread().
@@ -2305,16 +2223,15 @@ static int worker_thread(void *__worker)
{
struct worker *worker = __worker;
struct worker_pool *pool = worker->pool;
- struct global_cwq *gcwq = pool->gcwq;
/* tell the scheduler that this is a workqueue worker */
worker->task->flags |= PF_WQ_WORKER;
woke_up:
- spin_lock_irq(&gcwq->lock);
+ spin_lock_irq(&pool->lock);
/* we are off idle list if destruction or rebind is requested */
if (unlikely(list_empty(&worker->entry))) {
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&pool->lock);
/* if DIE is set, destruction is requested */
if (worker->flags & WORKER_DIE) {
@@ -2373,52 +2290,59 @@ sleep:
goto recheck;
/*
- * gcwq->lock is held and there's no work to process and no
- * need to manage, sleep. Workers are woken up only while
- * holding gcwq->lock or from local cpu, so setting the
- * current state before releasing gcwq->lock is enough to
- * prevent losing any event.
+ * pool->lock is held and there's no work to process and no need to
+ * manage, sleep. Workers are woken up only while holding
+ * pool->lock or from local cpu, so setting the current state
+ * before releasing pool->lock is enough to prevent losing any
+ * event.
*/
worker_enter_idle(worker);
__set_current_state(TASK_INTERRUPTIBLE);
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&pool->lock);
schedule();
goto woke_up;
}
/**
* rescuer_thread - the rescuer thread function
- * @__wq: the associated workqueue
+ * @__rescuer: self
*
* Workqueue rescuer thread function. There's one rescuer for each
* workqueue which has WQ_RESCUER set.
*
- * Regular work processing on a gcwq may block trying to create a new
+ * Regular work processing on a pool may block trying to create a new
* worker which uses GFP_KERNEL allocation which has slight chance of
* developing into deadlock if some works currently on the same queue
* need to be processed to satisfy the GFP_KERNEL allocation. This is
* the problem rescuer solves.
*
- * When such condition is possible, the gcwq summons rescuers of all
- * workqueues which have works queued on the gcwq and let them process
+ * When such condition is possible, the pool summons rescuers of all
+ * workqueues which have works queued on the pool and let them process
* those works so that forward progress can be guaranteed.
*
* This should happen rarely.
*/
-static int rescuer_thread(void *__wq)
+static int rescuer_thread(void *__rescuer)
{
- struct workqueue_struct *wq = __wq;
- struct worker *rescuer = wq->rescuer;
+ struct worker *rescuer = __rescuer;
+ struct workqueue_struct *wq = rescuer->rescue_wq;
struct list_head *scheduled = &rescuer->scheduled;
bool is_unbound = wq->flags & WQ_UNBOUND;
unsigned int cpu;
set_user_nice(current, RESCUER_NICE_LEVEL);
+
+ /*
+ * Mark rescuer as worker too. As WORKER_PREP is never cleared, it
+ * doesn't participate in concurrency management.
+ */
+ rescuer->task->flags |= PF_WQ_WORKER;
repeat:
set_current_state(TASK_INTERRUPTIBLE);
if (kthread_should_stop()) {
__set_current_state(TASK_RUNNING);
+ rescuer->task->flags &= ~PF_WQ_WORKER;
return 0;
}
@@ -2428,9 +2352,8 @@ repeat:
*/
for_each_mayday_cpu(cpu, wq->mayday_mask) {
unsigned int tcpu = is_unbound ? WORK_CPU_UNBOUND : cpu;
- struct cpu_workqueue_struct *cwq = get_cwq(tcpu, wq);
- struct worker_pool *pool = cwq->pool;
- struct global_cwq *gcwq = pool->gcwq;
+ struct pool_workqueue *pwq = get_pwq(tcpu, wq);
+ struct worker_pool *pool = pwq->pool;
struct work_struct *work, *n;
__set_current_state(TASK_RUNNING);
@@ -2446,22 +2369,24 @@ repeat:
*/
BUG_ON(!list_empty(&rescuer->scheduled));
list_for_each_entry_safe(work, n, &pool->worklist, entry)
- if (get_work_cwq(work) == cwq)
+ if (get_work_pwq(work) == pwq)
move_linked_works(work, scheduled, &n);
process_scheduled_works(rescuer);
/*
- * Leave this gcwq. If keep_working() is %true, notify a
+ * Leave this pool. If keep_working() is %true, notify a
* regular worker; otherwise, we end up with 0 concurrency
* and stalling the execution.
*/
if (keep_working(pool))
wake_up_worker(pool);
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&pool->lock);
}
+ /* rescuers should never participate in concurrency management */
+ WARN_ON_ONCE(!(rescuer->flags & WORKER_NOT_RUNNING));
schedule();
goto repeat;
}
@@ -2479,7 +2404,7 @@ static void wq_barrier_func(struct work_struct *work)
/**
* insert_wq_barrier - insert a barrier work
- * @cwq: cwq to insert barrier into
+ * @pwq: pwq to insert barrier into
* @barr: wq_barrier to insert
* @target: target work to attach @barr to
* @worker: worker currently executing @target, NULL if @target is not executing
@@ -2496,12 +2421,12 @@ static void wq_barrier_func(struct work_struct *work)
* after a work with LINKED flag set.
*
* Note that when @worker is non-NULL, @target may be modified
- * underneath us, so we can't reliably determine cwq from @target.
+ * underneath us, so we can't reliably determine pwq from @target.
*
* CONTEXT:
- * spin_lock_irq(gcwq->lock).
+ * spin_lock_irq(pool->lock).
*/
-static void insert_wq_barrier(struct cpu_workqueue_struct *cwq,
+static void insert_wq_barrier(struct pool_workqueue *pwq,
struct wq_barrier *barr,
struct work_struct *target, struct worker *worker)
{
@@ -2509,7 +2434,7 @@ static void insert_wq_barrier(struct cpu_workqueue_struct *cwq,
unsigned int linked = 0;
/*
- * debugobject calls are safe here even with gcwq->lock locked
+ * debugobject calls are safe here even with pool->lock locked
* as we know for sure that this will not trigger any of the
* checks and call back into the fixup functions where we
* might deadlock.
@@ -2534,23 +2459,23 @@ static void insert_wq_barrier(struct cpu_workqueue_struct *cwq,
}
debug_work_activate(&barr->work);
- insert_work(cwq, &barr->work, head,
+ insert_work(pwq, &barr->work, head,
work_color_to_flags(WORK_NO_COLOR) | linked);
}
/**
- * flush_workqueue_prep_cwqs - prepare cwqs for workqueue flushing
+ * flush_workqueue_prep_pwqs - prepare pwqs for workqueue flushing
* @wq: workqueue being flushed
* @flush_color: new flush color, < 0 for no-op
* @work_color: new work color, < 0 for no-op
*
- * Prepare cwqs for workqueue flushing.
+ * Prepare pwqs for workqueue flushing.
*
- * If @flush_color is non-negative, flush_color on all cwqs should be
- * -1. If no cwq has in-flight commands at the specified color, all
- * cwq->flush_color's stay at -1 and %false is returned. If any cwq
- * has in flight commands, its cwq->flush_color is set to
- * @flush_color, @wq->nr_cwqs_to_flush is updated accordingly, cwq
+ * If @flush_color is non-negative, flush_color on all pwqs should be
+ * -1. If no pwq has in-flight commands at the specified color, all
+ * pwq->flush_color's stay at -1 and %false is returned. If any pwq
+ * has in flight commands, its pwq->flush_color is set to
+ * @flush_color, @wq->nr_pwqs_to_flush is updated accordingly, pwq
* wakeup logic is armed and %true is returned.
*
* The caller should have initialized @wq->first_flusher prior to
@@ -2558,7 +2483,7 @@ static void insert_wq_barrier(struct cpu_workqueue_struct *cwq,
* @flush_color is negative, no flush color update is done and %false
* is returned.
*
- * If @work_color is non-negative, all cwqs should have the same
+ * If @work_color is non-negative, all pwqs should have the same
* work_color which is previous to @work_color and all will be
* advanced to @work_color.
*
@@ -2569,42 +2494,42 @@ static void insert_wq_barrier(struct cpu_workqueue_struct *cwq,
* %true if @flush_color >= 0 and there's something to flush. %false
* otherwise.
*/
-static bool flush_workqueue_prep_cwqs(struct workqueue_struct *wq,
+static bool flush_workqueue_prep_pwqs(struct workqueue_struct *wq,
int flush_color, int work_color)
{
bool wait = false;
unsigned int cpu;
if (flush_color >= 0) {
- BUG_ON(atomic_read(&wq->nr_cwqs_to_flush));
- atomic_set(&wq->nr_cwqs_to_flush, 1);
+ BUG_ON(atomic_read(&wq->nr_pwqs_to_flush));
+ atomic_set(&wq->nr_pwqs_to_flush, 1);
}
- for_each_cwq_cpu(cpu, wq) {
- struct cpu_workqueue_struct *cwq = get_cwq(cpu, wq);
- struct global_cwq *gcwq = cwq->pool->gcwq;
+ for_each_pwq_cpu(cpu, wq) {
+ struct pool_workqueue *pwq = get_pwq(cpu, wq);
+ struct worker_pool *pool = pwq->pool;
- spin_lock_irq(&gcwq->lock);
+ spin_lock_irq(&pool->lock);
if (flush_color >= 0) {
- BUG_ON(cwq->flush_color != -1);
+ BUG_ON(pwq->flush_color != -1);
- if (cwq->nr_in_flight[flush_color]) {
- cwq->flush_color = flush_color;
- atomic_inc(&wq->nr_cwqs_to_flush);
+ if (pwq->nr_in_flight[flush_color]) {
+ pwq->flush_color = flush_color;
+ atomic_inc(&wq->nr_pwqs_to_flush);
wait = true;
}
}
if (work_color >= 0) {
- BUG_ON(work_color != work_next_color(cwq->work_color));
- cwq->work_color = work_color;
+ BUG_ON(work_color != work_next_color(pwq->work_color));
+ pwq->work_color = work_color;
}
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&pool->lock);
}
- if (flush_color >= 0 && atomic_dec_and_test(&wq->nr_cwqs_to_flush))
+ if (flush_color >= 0 && atomic_dec_and_test(&wq->nr_pwqs_to_flush))
complete(&wq->first_flusher->done);
return wait;
@@ -2655,7 +2580,7 @@ void flush_workqueue(struct workqueue_struct *wq)
wq->first_flusher = &this_flusher;
- if (!flush_workqueue_prep_cwqs(wq, wq->flush_color,
+ if (!flush_workqueue_prep_pwqs(wq, wq->flush_color,
wq->work_color)) {
/* nothing to flush, done */
wq->flush_color = next_color;
@@ -2666,7 +2591,7 @@ void flush_workqueue(struct workqueue_struct *wq)
/* wait in queue */
BUG_ON(wq->flush_color == this_flusher.flush_color);
list_add_tail(&this_flusher.list, &wq->flusher_queue);
- flush_workqueue_prep_cwqs(wq, -1, wq->work_color);
+ flush_workqueue_prep_pwqs(wq, -1, wq->work_color);
}
} else {
/*
@@ -2733,7 +2658,7 @@ void flush_workqueue(struct workqueue_struct *wq)
list_splice_tail_init(&wq->flusher_overflow,
&wq->flusher_queue);
- flush_workqueue_prep_cwqs(wq, -1, wq->work_color);
+ flush_workqueue_prep_pwqs(wq, -1, wq->work_color);
}
if (list_empty(&wq->flusher_queue)) {
@@ -2743,7 +2668,7 @@ void flush_workqueue(struct workqueue_struct *wq)
/*
* Need to flush more colors. Make the next flusher
- * the new first flusher and arm cwqs.
+ * the new first flusher and arm pwqs.
*/
BUG_ON(wq->flush_color == wq->work_color);
BUG_ON(wq->flush_color != next->flush_color);
@@ -2751,7 +2676,7 @@ void flush_workqueue(struct workqueue_struct *wq)
list_del_init(&next->list);
wq->first_flusher = next;
- if (flush_workqueue_prep_cwqs(wq, wq->flush_color, -1))
+ if (flush_workqueue_prep_pwqs(wq, wq->flush_color, -1))
break;
/*
@@ -2794,13 +2719,13 @@ void drain_workqueue(struct workqueue_struct *wq)
reflush:
flush_workqueue(wq);
- for_each_cwq_cpu(cpu, wq) {
- struct cpu_workqueue_struct *cwq = get_cwq(cpu, wq);
+ for_each_pwq_cpu(cpu, wq) {
+ struct pool_workqueue *pwq = get_pwq(cpu, wq);
bool drained;
- spin_lock_irq(&cwq->pool->gcwq->lock);
- drained = !cwq->nr_active && list_empty(&cwq->delayed_works);
- spin_unlock_irq(&cwq->pool->gcwq->lock);
+ spin_lock_irq(&pwq->pool->lock);
+ drained = !pwq->nr_active && list_empty(&pwq->delayed_works);
+ spin_unlock_irq(&pwq->pool->lock);
if (drained)
continue;
@@ -2822,34 +2747,29 @@ EXPORT_SYMBOL_GPL(drain_workqueue);
static bool start_flush_work(struct work_struct *work, struct wq_barrier *barr)
{
struct worker *worker = NULL;
- struct global_cwq *gcwq;
- struct cpu_workqueue_struct *cwq;
+ struct worker_pool *pool;
+ struct pool_workqueue *pwq;
might_sleep();
- gcwq = get_work_gcwq(work);
- if (!gcwq)
+ pool = get_work_pool(work);
+ if (!pool)
return false;
- spin_lock_irq(&gcwq->lock);
- if (!list_empty(&work->entry)) {
- /*
- * See the comment near try_to_grab_pending()->smp_rmb().
- * If it was re-queued to a different gcwq under us, we
- * are not going to wait.
- */
- smp_rmb();
- cwq = get_work_cwq(work);
- if (unlikely(!cwq || gcwq != cwq->pool->gcwq))
+ spin_lock_irq(&pool->lock);
+ /* see the comment in try_to_grab_pending() with the same code */
+ pwq = get_work_pwq(work);
+ if (pwq) {
+ if (unlikely(pwq->pool != pool))
goto already_gone;
} else {
- worker = find_worker_executing_work(gcwq, work);
+ worker = find_worker_executing_work(pool, work);
if (!worker)
goto already_gone;
- cwq = worker->current_cwq;
+ pwq = worker->current_pwq;
}
- insert_wq_barrier(cwq, barr, work, worker);
- spin_unlock_irq(&gcwq->lock);
+ insert_wq_barrier(pwq, barr, work, worker);
+ spin_unlock_irq(&pool->lock);
/*
* If @max_active is 1 or rescuer is in use, flushing another work
@@ -2857,15 +2777,15 @@ static bool start_flush_work(struct work_struct *work, struct wq_barrier *barr)
* flusher is not running on the same workqueue by verifying write
* access.
*/
- if (cwq->wq->saved_max_active == 1 || cwq->wq->flags & WQ_RESCUER)
- lock_map_acquire(&cwq->wq->lockdep_map);
+ if (pwq->wq->saved_max_active == 1 || pwq->wq->flags & WQ_RESCUER)
+ lock_map_acquire(&pwq->wq->lockdep_map);
else
- lock_map_acquire_read(&cwq->wq->lockdep_map);
- lock_map_release(&cwq->wq->lockdep_map);
+ lock_map_acquire_read(&pwq->wq->lockdep_map);
+ lock_map_release(&pwq->wq->lockdep_map);
return true;
already_gone:
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&pool->lock);
return false;
}
@@ -2961,8 +2881,7 @@ bool flush_delayed_work(struct delayed_work *dwork)
{
local_irq_disable();
if (del_timer_sync(&dwork->timer))
- __queue_work(dwork->cpu,
- get_work_cwq(&dwork->work)->wq, &dwork->work);
+ __queue_work(dwork->cpu, dwork->wq, &dwork->work);
local_irq_enable();
return flush_work(&dwork->work);
}
@@ -2992,7 +2911,8 @@ bool cancel_delayed_work(struct delayed_work *dwork)
if (unlikely(ret < 0))
return false;
- set_work_cpu_and_clear_pending(&dwork->work, work_cpu(&dwork->work));
+ set_work_pool_and_clear_pending(&dwork->work,
+ get_work_pool_id(&dwork->work));
local_irq_restore(flags);
return ret;
}
@@ -3171,46 +3091,46 @@ int keventd_up(void)
return system_wq != NULL;
}
-static int alloc_cwqs(struct workqueue_struct *wq)
+static int alloc_pwqs(struct workqueue_struct *wq)
{
/*
- * cwqs are forced aligned according to WORK_STRUCT_FLAG_BITS.
+ * pwqs are forced aligned according to WORK_STRUCT_FLAG_BITS.
* Make sure that the alignment isn't lower than that of
* unsigned long long.
*/
- const size_t size = sizeof(struct cpu_workqueue_struct);
+ const size_t size = sizeof(struct pool_workqueue);
const size_t align = max_t(size_t, 1 << WORK_STRUCT_FLAG_BITS,
__alignof__(unsigned long long));
if (!(wq->flags & WQ_UNBOUND))
- wq->cpu_wq.pcpu = __alloc_percpu(size, align);
+ wq->pool_wq.pcpu = __alloc_percpu(size, align);
else {
void *ptr;
/*
- * Allocate enough room to align cwq and put an extra
+ * Allocate enough room to align pwq and put an extra
* pointer at the end pointing back to the originally
* allocated pointer which will be used for free.
*/
ptr = kzalloc(size + align + sizeof(void *), GFP_KERNEL);
if (ptr) {
- wq->cpu_wq.single = PTR_ALIGN(ptr, align);
- *(void **)(wq->cpu_wq.single + 1) = ptr;
+ wq->pool_wq.single = PTR_ALIGN(ptr, align);
+ *(void **)(wq->pool_wq.single + 1) = ptr;
}
}
/* just in case, make sure it's actually aligned */
- BUG_ON(!IS_ALIGNED(wq->cpu_wq.v, align));
- return wq->cpu_wq.v ? 0 : -ENOMEM;
+ BUG_ON(!IS_ALIGNED(wq->pool_wq.v, align));
+ return wq->pool_wq.v ? 0 : -ENOMEM;
}
-static void free_cwqs(struct workqueue_struct *wq)
+static void free_pwqs(struct workqueue_struct *wq)
{
if (!(wq->flags & WQ_UNBOUND))
- free_percpu(wq->cpu_wq.pcpu);
- else if (wq->cpu_wq.single) {
- /* the pointer to free is stored right after the cwq */
- kfree(*(void **)(wq->cpu_wq.single + 1));
+ free_percpu(wq->pool_wq.pcpu);
+ else if (wq->pool_wq.single) {
+ /* the pointer to free is stored right after the pwq */
+ kfree(*(void **)(wq->pool_wq.single + 1));
}
}
@@ -3264,27 +3184,25 @@ struct workqueue_struct *__alloc_workqueue_key(const char *fmt,
wq->flags = flags;
wq->saved_max_active = max_active;
mutex_init(&wq->flush_mutex);
- atomic_set(&wq->nr_cwqs_to_flush, 0);
+ atomic_set(&wq->nr_pwqs_to_flush, 0);
INIT_LIST_HEAD(&wq->flusher_queue);
INIT_LIST_HEAD(&wq->flusher_overflow);
lockdep_init_map(&wq->lockdep_map, lock_name, key, 0);
INIT_LIST_HEAD(&wq->list);
- if (alloc_cwqs(wq) < 0)
+ if (alloc_pwqs(wq) < 0)
goto err;
- for_each_cwq_cpu(cpu, wq) {
- struct cpu_workqueue_struct *cwq = get_cwq(cpu, wq);
- struct global_cwq *gcwq = get_gcwq(cpu);
- int pool_idx = (bool)(flags & WQ_HIGHPRI);
-
- BUG_ON((unsigned long)cwq & WORK_STRUCT_FLAG_MASK);
- cwq->pool = &gcwq->pools[pool_idx];
- cwq->wq = wq;
- cwq->flush_color = -1;
- cwq->max_active = max_active;
- INIT_LIST_HEAD(&cwq->delayed_works);
+ for_each_pwq_cpu(cpu, wq) {
+ struct pool_workqueue *pwq = get_pwq(cpu, wq);
+
+ BUG_ON((unsigned long)pwq & WORK_STRUCT_FLAG_MASK);
+ pwq->pool = get_std_worker_pool(cpu, flags & WQ_HIGHPRI);
+ pwq->wq = wq;
+ pwq->flush_color = -1;
+ pwq->max_active = max_active;
+ INIT_LIST_HEAD(&pwq->delayed_works);
}
if (flags & WQ_RESCUER) {
@@ -3297,7 +3215,8 @@ struct workqueue_struct *__alloc_workqueue_key(const char *fmt,
if (!rescuer)
goto err;
- rescuer->task = kthread_create(rescuer_thread, wq, "%s",
+ rescuer->rescue_wq = wq;
+ rescuer->task = kthread_create(rescuer_thread, rescuer, "%s",
wq->name);
if (IS_ERR(rescuer->task))
goto err;
@@ -3314,8 +3233,8 @@ struct workqueue_struct *__alloc_workqueue_key(const char *fmt,
spin_lock(&workqueue_lock);
if (workqueue_freezing && wq->flags & WQ_FREEZABLE)
- for_each_cwq_cpu(cpu, wq)
- get_cwq(cpu, wq)->max_active = 0;
+ for_each_pwq_cpu(cpu, wq)
+ get_pwq(cpu, wq)->max_active = 0;
list_add(&wq->list, &workqueues);
@@ -3324,7 +3243,7 @@ struct workqueue_struct *__alloc_workqueue_key(const char *fmt,
return wq;
err:
if (wq) {
- free_cwqs(wq);
+ free_pwqs(wq);
free_mayday_mask(wq->mayday_mask);
kfree(wq->rescuer);
kfree(wq);
@@ -3355,14 +3274,14 @@ void destroy_workqueue(struct workqueue_struct *wq)
spin_unlock(&workqueue_lock);
/* sanity check */
- for_each_cwq_cpu(cpu, wq) {
- struct cpu_workqueue_struct *cwq = get_cwq(cpu, wq);
+ for_each_pwq_cpu(cpu, wq) {
+ struct pool_workqueue *pwq = get_pwq(cpu, wq);
int i;
for (i = 0; i < WORK_NR_COLORS; i++)
- BUG_ON(cwq->nr_in_flight[i]);
- BUG_ON(cwq->nr_active);
- BUG_ON(!list_empty(&cwq->delayed_works));
+ BUG_ON(pwq->nr_in_flight[i]);
+ BUG_ON(pwq->nr_active);
+ BUG_ON(!list_empty(&pwq->delayed_works));
}
if (wq->flags & WQ_RESCUER) {
@@ -3371,29 +3290,29 @@ void destroy_workqueue(struct workqueue_struct *wq)
kfree(wq->rescuer);
}
- free_cwqs(wq);
+ free_pwqs(wq);
kfree(wq);
}
EXPORT_SYMBOL_GPL(destroy_workqueue);
/**
- * cwq_set_max_active - adjust max_active of a cwq
- * @cwq: target cpu_workqueue_struct
+ * pwq_set_max_active - adjust max_active of a pwq
+ * @pwq: target pool_workqueue
* @max_active: new max_active value.
*
- * Set @cwq->max_active to @max_active and activate delayed works if
+ * Set @pwq->max_active to @max_active and activate delayed works if
* increased.
*
* CONTEXT:
- * spin_lock_irq(gcwq->lock).
+ * spin_lock_irq(pool->lock).
*/
-static void cwq_set_max_active(struct cpu_workqueue_struct *cwq, int max_active)
+static void pwq_set_max_active(struct pool_workqueue *pwq, int max_active)
{
- cwq->max_active = max_active;
+ pwq->max_active = max_active;
- while (!list_empty(&cwq->delayed_works) &&
- cwq->nr_active < cwq->max_active)
- cwq_activate_first_delayed(cwq);
+ while (!list_empty(&pwq->delayed_works) &&
+ pwq->nr_active < pwq->max_active)
+ pwq_activate_first_delayed(pwq);
}
/**
@@ -3416,16 +3335,17 @@ void workqueue_set_max_active(struct workqueue_struct *wq, int max_active)
wq->saved_max_active = max_active;
- for_each_cwq_cpu(cpu, wq) {
- struct global_cwq *gcwq = get_gcwq(cpu);
+ for_each_pwq_cpu(cpu, wq) {
+ struct pool_workqueue *pwq = get_pwq(cpu, wq);
+ struct worker_pool *pool = pwq->pool;
- spin_lock_irq(&gcwq->lock);
+ spin_lock_irq(&pool->lock);
if (!(wq->flags & WQ_FREEZABLE) ||
- !(gcwq->flags & GCWQ_FREEZING))
- cwq_set_max_active(get_cwq(gcwq->cpu, wq), max_active);
+ !(pool->flags & POOL_FREEZING))
+ pwq_set_max_active(pwq, max_active);
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&pool->lock);
}
spin_unlock(&workqueue_lock);
@@ -3446,57 +3366,38 @@ EXPORT_SYMBOL_GPL(workqueue_set_max_active);
*/
bool workqueue_congested(unsigned int cpu, struct workqueue_struct *wq)
{
- struct cpu_workqueue_struct *cwq = get_cwq(cpu, wq);
+ struct pool_workqueue *pwq = get_pwq(cpu, wq);
- return !list_empty(&cwq->delayed_works);
+ return !list_empty(&pwq->delayed_works);
}
EXPORT_SYMBOL_GPL(workqueue_congested);
/**
- * work_cpu - return the last known associated cpu for @work
- * @work: the work of interest
- *
- * RETURNS:
- * CPU number if @work was ever queued. WORK_CPU_NONE otherwise.
- */
-unsigned int work_cpu(struct work_struct *work)
-{
- struct global_cwq *gcwq = get_work_gcwq(work);
-
- return gcwq ? gcwq->cpu : WORK_CPU_NONE;
-}
-EXPORT_SYMBOL_GPL(work_cpu);
-
-/**
* work_busy - test whether a work is currently pending or running
* @work: the work to be tested
*
* Test whether @work is currently pending or running. There is no
* synchronization around this function and the test result is
* unreliable and only useful as advisory hints or for debugging.
- * Especially for reentrant wqs, the pending state might hide the
- * running state.
*
* RETURNS:
* OR'd bitmask of WORK_BUSY_* bits.
*/
unsigned int work_busy(struct work_struct *work)
{
- struct global_cwq *gcwq = get_work_gcwq(work);
+ struct worker_pool *pool = get_work_pool(work);
unsigned long flags;
unsigned int ret = 0;
- if (!gcwq)
- return 0;
-
- spin_lock_irqsave(&gcwq->lock, flags);
-
if (work_pending(work))
ret |= WORK_BUSY_PENDING;
- if (find_worker_executing_work(gcwq, work))
- ret |= WORK_BUSY_RUNNING;
- spin_unlock_irqrestore(&gcwq->lock, flags);
+ if (pool) {
+ spin_lock_irqsave(&pool->lock, flags);
+ if (find_worker_executing_work(pool, work))
+ ret |= WORK_BUSY_RUNNING;
+ spin_unlock_irqrestore(&pool->lock, flags);
+ }
return ret;
}
@@ -3506,65 +3407,49 @@ EXPORT_SYMBOL_GPL(work_busy);
* CPU hotplug.
*
* There are two challenges in supporting CPU hotplug. Firstly, there
- * are a lot of assumptions on strong associations among work, cwq and
- * gcwq which make migrating pending and scheduled works very
+ * are a lot of assumptions on strong associations among work, pwq and
+ * pool which make migrating pending and scheduled works very
* difficult to implement without impacting hot paths. Secondly,
- * gcwqs serve mix of short, long and very long running works making
+ * worker pools serve mix of short, long and very long running works making
* blocked draining impractical.
*
- * This is solved by allowing a gcwq to be disassociated from the CPU
+ * This is solved by allowing the pools to be disassociated from the CPU
* running as an unbound one and allowing it to be reattached later if the
* cpu comes back online.
*/
-/* claim manager positions of all pools */
-static void gcwq_claim_assoc_and_lock(struct global_cwq *gcwq)
+static void wq_unbind_fn(struct work_struct *work)
{
- struct worker_pool *pool;
-
- for_each_worker_pool(pool, gcwq)
- mutex_lock_nested(&pool->assoc_mutex, pool - gcwq->pools);
- spin_lock_irq(&gcwq->lock);
-}
-
-/* release manager positions */
-static void gcwq_release_assoc_and_unlock(struct global_cwq *gcwq)
-{
- struct worker_pool *pool;
-
- spin_unlock_irq(&gcwq->lock);
- for_each_worker_pool(pool, gcwq)
- mutex_unlock(&pool->assoc_mutex);
-}
-
-static void gcwq_unbind_fn(struct work_struct *work)
-{
- struct global_cwq *gcwq = get_gcwq(smp_processor_id());
+ int cpu = smp_processor_id();
struct worker_pool *pool;
struct worker *worker;
struct hlist_node *pos;
int i;
- BUG_ON(gcwq->cpu != smp_processor_id());
+ for_each_std_worker_pool(pool, cpu) {
+ BUG_ON(cpu != smp_processor_id());
- gcwq_claim_assoc_and_lock(gcwq);
+ mutex_lock(&pool->assoc_mutex);
+ spin_lock_irq(&pool->lock);
- /*
- * We've claimed all manager positions. Make all workers unbound
- * and set DISASSOCIATED. Before this, all workers except for the
- * ones which are still executing works from before the last CPU
- * down must be on the cpu. After this, they may become diasporas.
- */
- for_each_worker_pool(pool, gcwq)
+ /*
+ * We've claimed all manager positions. Make all workers
+ * unbound and set DISASSOCIATED. Before this, all workers
+ * except for the ones which are still executing works from
+ * before the last CPU down must be on the cpu. After
+ * this, they may become diasporas.
+ */
list_for_each_entry(worker, &pool->idle_list, entry)
worker->flags |= WORKER_UNBOUND;
- for_each_busy_worker(worker, i, pos, gcwq)
- worker->flags |= WORKER_UNBOUND;
+ for_each_busy_worker(worker, i, pos, pool)
+ worker->flags |= WORKER_UNBOUND;
- gcwq->flags |= GCWQ_DISASSOCIATED;
+ pool->flags |= POOL_DISASSOCIATED;
- gcwq_release_assoc_and_unlock(gcwq);
+ spin_unlock_irq(&pool->lock);
+ mutex_unlock(&pool->assoc_mutex);
+ }
/*
* Call schedule() so that we cross rq->lock and thus can guarantee
@@ -3576,16 +3461,16 @@ static void gcwq_unbind_fn(struct work_struct *work)
/*
* Sched callbacks are disabled now. Zap nr_running. After this,
* nr_running stays zero and need_more_worker() and keep_working()
- * are always true as long as the worklist is not empty. @gcwq now
- * behaves as unbound (in terms of concurrency management) gcwq
- * which is served by workers tied to the CPU.
+ * are always true as long as the worklist is not empty. Pools on
+ * @cpu now behave as unbound (in terms of concurrency management)
+ * pools which are served by workers tied to the CPU.
*
* On return from this function, the current worker would trigger
* unbound chain execution of pending work items if other workers
* didn't already.
*/
- for_each_worker_pool(pool, gcwq)
- atomic_set(get_pool_nr_running(pool), 0);
+ for_each_std_worker_pool(pool, cpu)
+ atomic_set(&pool->nr_running, 0);
}
/*
@@ -3597,12 +3482,11 @@ static int __cpuinit workqueue_cpu_up_callback(struct notifier_block *nfb,
void *hcpu)
{
unsigned int cpu = (unsigned long)hcpu;
- struct global_cwq *gcwq = get_gcwq(cpu);
struct worker_pool *pool;
switch (action & ~CPU_TASKS_FROZEN) {
case CPU_UP_PREPARE:
- for_each_worker_pool(pool, gcwq) {
+ for_each_std_worker_pool(pool, cpu) {
struct worker *worker;
if (pool->nr_workers)
@@ -3612,18 +3496,24 @@ static int __cpuinit workqueue_cpu_up_callback(struct notifier_block *nfb,
if (!worker)
return NOTIFY_BAD;
- spin_lock_irq(&gcwq->lock);
+ spin_lock_irq(&pool->lock);
start_worker(worker);
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&pool->lock);
}
break;
case CPU_DOWN_FAILED:
case CPU_ONLINE:
- gcwq_claim_assoc_and_lock(gcwq);
- gcwq->flags &= ~GCWQ_DISASSOCIATED;
- rebind_workers(gcwq);
- gcwq_release_assoc_and_unlock(gcwq);
+ for_each_std_worker_pool(pool, cpu) {
+ mutex_lock(&pool->assoc_mutex);
+ spin_lock_irq(&pool->lock);
+
+ pool->flags &= ~POOL_DISASSOCIATED;
+ rebind_workers(pool);
+
+ spin_unlock_irq(&pool->lock);
+ mutex_unlock(&pool->assoc_mutex);
+ }
break;
}
return NOTIFY_OK;
@@ -3643,7 +3533,7 @@ static int __cpuinit workqueue_cpu_down_callback(struct notifier_block *nfb,
switch (action & ~CPU_TASKS_FROZEN) {
case CPU_DOWN_PREPARE:
/* unbinding should happen on the local CPU */
- INIT_WORK_ONSTACK(&unbind_work, gcwq_unbind_fn);
+ INIT_WORK_ONSTACK(&unbind_work, wq_unbind_fn);
queue_work_on(cpu, system_highpri_wq, &unbind_work);
flush_work(&unbind_work);
break;
@@ -3696,10 +3586,10 @@ EXPORT_SYMBOL_GPL(work_on_cpu);
*
* Start freezing workqueues. After this function returns, all freezable
* workqueues will queue new works to their frozen_works list instead of
- * gcwq->worklist.
+ * pool->worklist.
*
* CONTEXT:
- * Grabs and releases workqueue_lock and gcwq->lock's.
+ * Grabs and releases workqueue_lock and pool->lock's.
*/
void freeze_workqueues_begin(void)
{
@@ -3710,23 +3600,26 @@ void freeze_workqueues_begin(void)
BUG_ON(workqueue_freezing);
workqueue_freezing = true;
- for_each_gcwq_cpu(cpu) {
- struct global_cwq *gcwq = get_gcwq(cpu);
+ for_each_wq_cpu(cpu) {
+ struct worker_pool *pool;
struct workqueue_struct *wq;
- spin_lock_irq(&gcwq->lock);
+ for_each_std_worker_pool(pool, cpu) {
+ spin_lock_irq(&pool->lock);
- BUG_ON(gcwq->flags & GCWQ_FREEZING);
- gcwq->flags |= GCWQ_FREEZING;
+ WARN_ON_ONCE(pool->flags & POOL_FREEZING);
+ pool->flags |= POOL_FREEZING;
- list_for_each_entry(wq, &workqueues, list) {
- struct cpu_workqueue_struct *cwq = get_cwq(cpu, wq);
+ list_for_each_entry(wq, &workqueues, list) {
+ struct pool_workqueue *pwq = get_pwq(cpu, wq);
- if (cwq && wq->flags & WQ_FREEZABLE)
- cwq->max_active = 0;
- }
+ if (pwq && pwq->pool == pool &&
+ (wq->flags & WQ_FREEZABLE))
+ pwq->max_active = 0;
+ }
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&pool->lock);
+ }
}
spin_unlock(&workqueue_lock);
@@ -3754,20 +3647,20 @@ bool freeze_workqueues_busy(void)
BUG_ON(!workqueue_freezing);
- for_each_gcwq_cpu(cpu) {
+ for_each_wq_cpu(cpu) {
struct workqueue_struct *wq;
/*
* nr_active is monotonically decreasing. It's safe
* to peek without lock.
*/
list_for_each_entry(wq, &workqueues, list) {
- struct cpu_workqueue_struct *cwq = get_cwq(cpu, wq);
+ struct pool_workqueue *pwq = get_pwq(cpu, wq);
- if (!cwq || !(wq->flags & WQ_FREEZABLE))
+ if (!pwq || !(wq->flags & WQ_FREEZABLE))
continue;
- BUG_ON(cwq->nr_active < 0);
- if (cwq->nr_active) {
+ BUG_ON(pwq->nr_active < 0);
+ if (pwq->nr_active) {
busy = true;
goto out_unlock;
}
@@ -3782,10 +3675,10 @@ out_unlock:
* thaw_workqueues - thaw workqueues
*
* Thaw workqueues. Normal queueing is restored and all collected
- * frozen works are transferred to their respective gcwq worklists.
+ * frozen works are transferred to their respective pool worklists.
*
* CONTEXT:
- * Grabs and releases workqueue_lock and gcwq->lock's.
+ * Grabs and releases workqueue_lock and pool->lock's.
*/
void thaw_workqueues(void)
{
@@ -3796,30 +3689,31 @@ void thaw_workqueues(void)
if (!workqueue_freezing)
goto out_unlock;
- for_each_gcwq_cpu(cpu) {
- struct global_cwq *gcwq = get_gcwq(cpu);
+ for_each_wq_cpu(cpu) {
struct worker_pool *pool;
struct workqueue_struct *wq;
- spin_lock_irq(&gcwq->lock);
+ for_each_std_worker_pool(pool, cpu) {
+ spin_lock_irq(&pool->lock);
- BUG_ON(!(gcwq->flags & GCWQ_FREEZING));
- gcwq->flags &= ~GCWQ_FREEZING;
+ WARN_ON_ONCE(!(pool->flags & POOL_FREEZING));
+ pool->flags &= ~POOL_FREEZING;
- list_for_each_entry(wq, &workqueues, list) {
- struct cpu_workqueue_struct *cwq = get_cwq(cpu, wq);
+ list_for_each_entry(wq, &workqueues, list) {
+ struct pool_workqueue *pwq = get_pwq(cpu, wq);
- if (!cwq || !(wq->flags & WQ_FREEZABLE))
- continue;
+ if (!pwq || pwq->pool != pool ||
+ !(wq->flags & WQ_FREEZABLE))
+ continue;
- /* restore max_active and repopulate worklist */
- cwq_set_max_active(cwq, wq->saved_max_active);
- }
+ /* restore max_active and repopulate worklist */
+ pwq_set_max_active(pwq, wq->saved_max_active);
+ }
- for_each_worker_pool(pool, gcwq)
wake_up_worker(pool);
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&pool->lock);
+ }
}
workqueue_freezing = false;
@@ -3831,60 +3725,56 @@ out_unlock:
static int __init init_workqueues(void)
{
unsigned int cpu;
- int i;
- /* make sure we have enough bits for OFFQ CPU number */
- BUILD_BUG_ON((1LU << (BITS_PER_LONG - WORK_OFFQ_CPU_SHIFT)) <
- WORK_CPU_LAST);
+ /* make sure we have enough bits for OFFQ pool ID */
+ BUILD_BUG_ON((1LU << (BITS_PER_LONG - WORK_OFFQ_POOL_SHIFT)) <
+ WORK_CPU_END * NR_STD_WORKER_POOLS);
cpu_notifier(workqueue_cpu_up_callback, CPU_PRI_WORKQUEUE_UP);
hotcpu_notifier(workqueue_cpu_down_callback, CPU_PRI_WORKQUEUE_DOWN);
- /* initialize gcwqs */
- for_each_gcwq_cpu(cpu) {
- struct global_cwq *gcwq = get_gcwq(cpu);
+ /* initialize CPU pools */
+ for_each_wq_cpu(cpu) {
struct worker_pool *pool;
- spin_lock_init(&gcwq->lock);
- gcwq->cpu = cpu;
- gcwq->flags |= GCWQ_DISASSOCIATED;
-
- for (i = 0; i < BUSY_WORKER_HASH_SIZE; i++)
- INIT_HLIST_HEAD(&gcwq->busy_hash[i]);
-
- for_each_worker_pool(pool, gcwq) {
- pool->gcwq = gcwq;
+ for_each_std_worker_pool(pool, cpu) {
+ spin_lock_init(&pool->lock);
+ pool->cpu = cpu;
+ pool->flags |= POOL_DISASSOCIATED;
INIT_LIST_HEAD(&pool->worklist);
INIT_LIST_HEAD(&pool->idle_list);
+ hash_init(pool->busy_hash);
init_timer_deferrable(&pool->idle_timer);
pool->idle_timer.function = idle_worker_timeout;
pool->idle_timer.data = (unsigned long)pool;
- setup_timer(&pool->mayday_timer, gcwq_mayday_timeout,
+ setup_timer(&pool->mayday_timer, pool_mayday_timeout,
(unsigned long)pool);
mutex_init(&pool->assoc_mutex);
ida_init(&pool->worker_ida);
+
+ /* alloc pool ID */
+ BUG_ON(worker_pool_assign_id(pool));
}
}
/* create the initial worker */
- for_each_online_gcwq_cpu(cpu) {
- struct global_cwq *gcwq = get_gcwq(cpu);
+ for_each_online_wq_cpu(cpu) {
struct worker_pool *pool;
- if (cpu != WORK_CPU_UNBOUND)
- gcwq->flags &= ~GCWQ_DISASSOCIATED;
-
- for_each_worker_pool(pool, gcwq) {
+ for_each_std_worker_pool(pool, cpu) {
struct worker *worker;
+ if (cpu != WORK_CPU_UNBOUND)
+ pool->flags &= ~POOL_DISASSOCIATED;
+
worker = create_worker(pool);
BUG_ON(!worker);
- spin_lock_irq(&gcwq->lock);
+ spin_lock_irq(&pool->lock);
start_worker(worker);
- spin_unlock_irq(&gcwq->lock);
+ spin_unlock_irq(&pool->lock);
}
}
diff --git a/kernel/workqueue_internal.h b/kernel/workqueue_internal.h
new file mode 100644
index 00000000000..07650264ec1
--- /dev/null
+++ b/kernel/workqueue_internal.h
@@ -0,0 +1,65 @@
+/*
+ * kernel/workqueue_internal.h
+ *
+ * Workqueue internal header file. Only to be included by workqueue and
+ * core kernel subsystems.
+ */
+#ifndef _KERNEL_WORKQUEUE_INTERNAL_H
+#define _KERNEL_WORKQUEUE_INTERNAL_H
+
+#include <linux/workqueue.h>
+#include <linux/kthread.h>
+
+struct worker_pool;
+
+/*
+ * The poor guys doing the actual heavy lifting. All on-duty workers are
+ * either serving the manager role, on idle list or on busy hash. For
+ * details on the locking annotation (L, I, X...), refer to workqueue.c.
+ *
+ * Only to be used in workqueue and async.
+ */
+struct worker {
+ /* on idle list while idle, on busy hash table while busy */
+ union {
+ struct list_head entry; /* L: while idle */
+ struct hlist_node hentry; /* L: while busy */
+ };
+
+ struct work_struct *current_work; /* L: work being processed */
+ work_func_t current_func; /* L: current_work's fn */
+ struct pool_workqueue *current_pwq; /* L: current_work's pwq */
+ struct list_head scheduled; /* L: scheduled works */
+ struct task_struct *task; /* I: worker task */
+ struct worker_pool *pool; /* I: the associated pool */
+ /* 64 bytes boundary on 64bit, 32 on 32bit */
+ unsigned long last_active; /* L: last active timestamp */
+ unsigned int flags; /* X: flags */
+ int id; /* I: worker id */
+
+ /* for rebinding worker to CPU */
+ struct work_struct rebind_work; /* L: for busy worker */
+
+ /* used only by rescuers to point to the target workqueue */
+ struct workqueue_struct *rescue_wq; /* I: the workqueue to rescue */
+};
+
+/**
+ * current_wq_worker - return struct worker if %current is a workqueue worker
+ */
+static inline struct worker *current_wq_worker(void)
+{
+ if (current->flags & PF_WQ_WORKER)
+ return kthread_data(current);
+ return NULL;
+}
+
+/*
+ * Scheduler hooks for concurrency managed workqueue. Only to be used from
+ * sched.c and workqueue.c.
+ */
+void wq_worker_waking_up(struct task_struct *task, unsigned int cpu);
+struct task_struct *wq_worker_sleeping(struct task_struct *task,
+ unsigned int cpu);
+
+#endif /* _KERNEL_WORKQUEUE_INTERNAL_H */
diff --git a/kernel/workqueue_sched.h b/kernel/workqueue_sched.h
deleted file mode 100644
index 2d10fc98dc7..00000000000
--- a/kernel/workqueue_sched.h
+++ /dev/null
@@ -1,9 +0,0 @@
-/*
- * kernel/workqueue_sched.h
- *
- * Scheduler hooks for concurrency managed workqueue. Only to be
- * included from sched.c and workqueue.c.
- */
-void wq_worker_waking_up(struct task_struct *task, unsigned int cpu);
-struct task_struct *wq_worker_sleeping(struct task_struct *task,
- unsigned int cpu);