aboutsummaryrefslogtreecommitdiff
path: root/kernel
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2017-11-14 15:32:19 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2017-11-14 15:32:19 -0800
commite2c5923c349c1738fe8fda980874d93f6fb2e5b6 (patch)
treeb97a90170c45211bcc437761653aa8016c34afcd /kernel
parentabc36be236358162202e86ad88616ff95a755101 (diff)
parenta04b5de5050ab8b891128eb2c47a0916fe8622e1 (diff)
download96b-common-e2c5923c349c1738fe8fda980874d93f6fb2e5b6.tar.gz
Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-block
Pull core block layer updates from Jens Axboe: "This is the main pull request for block storage for 4.15-rc1. Nothing out of the ordinary in here, and no API changes or anything like that. Just various new features for drivers, core changes, etc. In particular, this pull request contains: - A patch series from Bart, closing the whole on blk/scsi-mq queue quescing. - A series from Christoph, building towards hidden gendisks (for multipath) and ability to move bio chains around. - NVMe - Support for native multipath for NVMe (Christoph). - Userspace notifications for AENs (Keith). - Command side-effects support (Keith). - SGL support (Chaitanya Kulkarni) - FC fixes and improvements (James Smart) - Lots of fixes and tweaks (Various) - bcache - New maintainer (Michael Lyle) - Writeback control improvements (Michael) - Various fixes (Coly, Elena, Eric, Liang, et al) - lightnvm updates, mostly centered around the pblk interface (Javier, Hans, and Rakesh). - Removal of unused bio/bvec kmap atomic interfaces (me, Christoph) - Writeback series that fix the much discussed hundreds of millions of sync-all units. This goes all the way, as discussed previously (me). - Fix for missing wakeup on writeback timer adjustments (Yafang Shao). - Fix laptop mode on blk-mq (me). - {mq,name} tupple lookup for IO schedulers, allowing us to have alias names. This means you can use 'deadline' on both !mq and on mq (where it's called mq-deadline). (me). - blktrace race fix, oopsing on sg load (me). - blk-mq optimizations (me). - Obscure waitqueue race fix for kyber (Omar). - NBD fixes (Josef). - Disable writeback throttling by default on bfq, like we do on cfq (Luca Miccio). - Series from Ming that enable us to treat flush requests on blk-mq like any other request. This is a really nice cleanup. - Series from Ming that improves merging on blk-mq with schedulers, getting us closer to flipping the switch on scsi-mq again. - BFQ updates (Paolo). - blk-mq atomic flags memory ordering fixes (Peter Z). - Loop cgroup support (Shaohua). - Lots of minor fixes from lots of different folks, both for core and driver code" * 'for-4.15/block' of git://git.kernel.dk/linux-block: (294 commits) nvme: fix visibility of "uuid" ns attribute blk-mq: fixup some comment typos and lengths ide: ide-atapi: fix compile error with defining macro DEBUG blk-mq: improve tag waiting setup for non-shared tags brd: remove unused brd_mutex blk-mq: only run the hardware queue if IO is pending block: avoid null pointer dereference on null disk fs: guard_bio_eod() needs to consider partitions xtensa/simdisk: fix compile error nvme: expose subsys attribute to sysfs nvme: create 'slaves' and 'holders' entries for hidden controllers block: create 'slaves' and 'holders' entries for hidden gendisks nvme: also expose the namespace identification sysfs files for mpath nodes nvme: implement multipath access to nvme subsystems nvme: track shared namespaces nvme: introduce a nvme_ns_ids structure nvme: track subsystems block, nvme: Introduce blk_mq_req_flags_t block, scsi: Make SCSI quiesce and resume work reliably block: Add the QUEUE_FLAG_PREEMPT_ONLY request queue flag ...
Diffstat (limited to 'kernel')
-rw-r--r--kernel/kthread.c66
-rw-r--r--kernel/sysctl.c5
-rw-r--r--kernel/trace/blktrace.c90
3 files changed, 132 insertions, 29 deletions
diff --git a/kernel/kthread.c b/kernel/kthread.c
index ba3992c8c375..8af313081b0d 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -20,7 +20,6 @@
#include <linux/freezer.h>
#include <linux/ptrace.h>
#include <linux/uaccess.h>
-#include <linux/cgroup.h>
#include <trace/events/sched.h>
static DEFINE_SPINLOCK(kthread_create_lock);
@@ -47,6 +46,9 @@ struct kthread {
void *data;
struct completion parked;
struct completion exited;
+#ifdef CONFIG_BLK_CGROUP
+ struct cgroup_subsys_state *blkcg_css;
+#endif
};
enum KTHREAD_BITS {
@@ -74,11 +76,17 @@ static inline struct kthread *to_kthread(struct task_struct *k)
void free_kthread_struct(struct task_struct *k)
{
+ struct kthread *kthread;
+
/*
* Can be NULL if this kthread was created by kernel_thread()
* or if kmalloc() in kthread() failed.
*/
- kfree(to_kthread(k));
+ kthread = to_kthread(k);
+#ifdef CONFIG_BLK_CGROUP
+ WARN_ON_ONCE(kthread && kthread->blkcg_css);
+#endif
+ kfree(kthread);
}
/**
@@ -196,7 +204,7 @@ static int kthread(void *_create)
struct kthread *self;
int ret;
- self = kmalloc(sizeof(*self), GFP_KERNEL);
+ self = kzalloc(sizeof(*self), GFP_KERNEL);
set_kthread_struct(self);
/* If user was SIGKILLed, I release the structure. */
@@ -212,7 +220,6 @@ static int kthread(void *_create)
do_exit(-ENOMEM);
}
- self->flags = 0;
self->data = data;
init_completion(&self->exited);
init_completion(&self->parked);
@@ -1152,3 +1159,54 @@ void kthread_destroy_worker(struct kthread_worker *worker)
kfree(worker);
}
EXPORT_SYMBOL(kthread_destroy_worker);
+
+#ifdef CONFIG_BLK_CGROUP
+/**
+ * kthread_associate_blkcg - associate blkcg to current kthread
+ * @css: the cgroup info
+ *
+ * Current thread must be a kthread. The thread is running jobs on behalf of
+ * other threads. In some cases, we expect the jobs attach cgroup info of
+ * original threads instead of that of current thread. This function stores
+ * original thread's cgroup info in current kthread context for later
+ * retrieval.
+ */
+void kthread_associate_blkcg(struct cgroup_subsys_state *css)
+{
+ struct kthread *kthread;
+
+ if (!(current->flags & PF_KTHREAD))
+ return;
+ kthread = to_kthread(current);
+ if (!kthread)
+ return;
+
+ if (kthread->blkcg_css) {
+ css_put(kthread->blkcg_css);
+ kthread->blkcg_css = NULL;
+ }
+ if (css) {
+ css_get(css);
+ kthread->blkcg_css = css;
+ }
+}
+EXPORT_SYMBOL(kthread_associate_blkcg);
+
+/**
+ * kthread_blkcg - get associated blkcg css of current kthread
+ *
+ * Current thread must be a kthread.
+ */
+struct cgroup_subsys_state *kthread_blkcg(void)
+{
+ struct kthread *kthread;
+
+ if (current->flags & PF_KTHREAD) {
+ kthread = to_kthread(current);
+ if (kthread)
+ return kthread->blkcg_css;
+ }
+ return NULL;
+}
+EXPORT_SYMBOL(kthread_blkcg);
+#endif
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index d9c31bc2eaea..9576bd582d4a 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -1342,11 +1342,6 @@ static struct ctl_table vm_table[] = {
.extra1 = &zero,
},
{
- .procname = "nr_pdflush_threads",
- .mode = 0444 /* read-only */,
- .proc_handler = pdflush_proc_obsolete,
- },
- {
.procname = "swappiness",
.data = &vm_swappiness,
.maxlen = sizeof(vm_swappiness),
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 45a3928544ce..206e0e2ace53 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -66,7 +66,8 @@ static struct tracer_flags blk_tracer_flags = {
};
/* Global reference count of probes */
-static atomic_t blk_probes_ref = ATOMIC_INIT(0);
+static DEFINE_MUTEX(blk_probe_mutex);
+static int blk_probes_ref;
static void blk_register_tracepoints(void);
static void blk_unregister_tracepoints(void);
@@ -329,14 +330,29 @@ static void blk_trace_free(struct blk_trace *bt)
kfree(bt);
}
+static void get_probe_ref(void)
+{
+ mutex_lock(&blk_probe_mutex);
+ if (++blk_probes_ref == 1)
+ blk_register_tracepoints();
+ mutex_unlock(&blk_probe_mutex);
+}
+
+static void put_probe_ref(void)
+{
+ mutex_lock(&blk_probe_mutex);
+ if (!--blk_probes_ref)
+ blk_unregister_tracepoints();
+ mutex_unlock(&blk_probe_mutex);
+}
+
static void blk_trace_cleanup(struct blk_trace *bt)
{
blk_trace_free(bt);
- if (atomic_dec_and_test(&blk_probes_ref))
- blk_unregister_tracepoints();
+ put_probe_ref();
}
-int blk_trace_remove(struct request_queue *q)
+static int __blk_trace_remove(struct request_queue *q)
{
struct blk_trace *bt;
@@ -349,6 +365,17 @@ int blk_trace_remove(struct request_queue *q)
return 0;
}
+
+int blk_trace_remove(struct request_queue *q)
+{
+ int ret;
+
+ mutex_lock(&q->blk_trace_mutex);
+ ret = __blk_trace_remove(q);
+ mutex_unlock(&q->blk_trace_mutex);
+
+ return ret;
+}
EXPORT_SYMBOL_GPL(blk_trace_remove);
static ssize_t blk_dropped_read(struct file *filp, char __user *buffer,
@@ -538,8 +565,7 @@ static int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
if (cmpxchg(&q->blk_trace, NULL, bt))
goto err;
- if (atomic_inc_return(&blk_probes_ref) == 1)
- blk_register_tracepoints();
+ get_probe_ref();
ret = 0;
err:
@@ -550,9 +576,8 @@ err:
return ret;
}
-int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
- struct block_device *bdev,
- char __user *arg)
+static int __blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
+ struct block_device *bdev, char __user *arg)
{
struct blk_user_trace_setup buts;
int ret;
@@ -571,6 +596,19 @@ int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
}
return 0;
}
+
+int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
+ struct block_device *bdev,
+ char __user *arg)
+{
+ int ret;
+
+ mutex_lock(&q->blk_trace_mutex);
+ ret = __blk_trace_setup(q, name, dev, bdev, arg);
+ mutex_unlock(&q->blk_trace_mutex);
+
+ return ret;
+}
EXPORT_SYMBOL_GPL(blk_trace_setup);
#if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64)
@@ -607,7 +645,7 @@ static int compat_blk_trace_setup(struct request_queue *q, char *name,
}
#endif
-int blk_trace_startstop(struct request_queue *q, int start)
+static int __blk_trace_startstop(struct request_queue *q, int start)
{
int ret;
struct blk_trace *bt = q->blk_trace;
@@ -646,6 +684,17 @@ int blk_trace_startstop(struct request_queue *q, int start)
return ret;
}
+
+int blk_trace_startstop(struct request_queue *q, int start)
+{
+ int ret;
+
+ mutex_lock(&q->blk_trace_mutex);
+ ret = __blk_trace_startstop(q, start);
+ mutex_unlock(&q->blk_trace_mutex);
+
+ return ret;
+}
EXPORT_SYMBOL_GPL(blk_trace_startstop);
/*
@@ -676,7 +725,7 @@ int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg)
switch (cmd) {
case BLKTRACESETUP:
bdevname(bdev, b);
- ret = blk_trace_setup(q, b, bdev->bd_dev, bdev, arg);
+ ret = __blk_trace_setup(q, b, bdev->bd_dev, bdev, arg);
break;
#if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64)
case BLKTRACESETUP32:
@@ -687,10 +736,10 @@ int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg)
case BLKTRACESTART:
start = 1;
case BLKTRACESTOP:
- ret = blk_trace_startstop(q, start);
+ ret = __blk_trace_startstop(q, start);
break;
case BLKTRACETEARDOWN:
- ret = blk_trace_remove(q);
+ ret = __blk_trace_remove(q);
break;
default:
ret = -ENOTTY;
@@ -708,10 +757,14 @@ int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg)
**/
void blk_trace_shutdown(struct request_queue *q)
{
+ mutex_lock(&q->blk_trace_mutex);
+
if (q->blk_trace) {
- blk_trace_startstop(q, 0);
- blk_trace_remove(q);
+ __blk_trace_startstop(q, 0);
+ __blk_trace_remove(q);
}
+
+ mutex_unlock(&q->blk_trace_mutex);
}
#ifdef CONFIG_BLK_CGROUP
@@ -1558,9 +1611,7 @@ static int blk_trace_remove_queue(struct request_queue *q)
if (bt == NULL)
return -EINVAL;
- if (atomic_dec_and_test(&blk_probes_ref))
- blk_unregister_tracepoints();
-
+ put_probe_ref();
blk_trace_free(bt);
return 0;
}
@@ -1591,8 +1642,7 @@ static int blk_trace_setup_queue(struct request_queue *q,
if (cmpxchg(&q->blk_trace, NULL, bt))
goto free_bt;
- if (atomic_inc_return(&blk_probes_ref) == 1)
- blk_register_tracepoints();
+ get_probe_ref();
return 0;
free_bt: