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-rw-r--r--include/linux/cpu.h2
-rw-r--r--kernel/cpu.c69
2 files changed, 31 insertions, 40 deletions
diff --git a/include/linux/cpu.h b/include/linux/cpu.h
index d2ca8c38f9c4..f2fb54938ee6 100644
--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -118,6 +118,7 @@ enum {
#ifdef CONFIG_SMP
+extern bool cpuhp_tasks_frozen;
/* Need to know about CPUs going up/down? */
#if defined(CONFIG_HOTPLUG_CPU) || !defined(MODULE)
#define cpu_notifier(fn, pri) { \
@@ -177,6 +178,7 @@ extern void cpu_maps_update_done(void);
#define cpu_notifier_register_done cpu_maps_update_done
#else /* CONFIG_SMP */
+#define cpuhp_tasks_frozen 0
#define cpu_notifier(fn, pri) do { (void)(fn); } while (0)
#define __cpu_notifier(fn, pri) do { (void)(fn); } while (0)
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 5b9d39633ce9..41a6cb85c0af 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -29,6 +29,8 @@
#ifdef CONFIG_SMP
/* Serializes the updates to cpu_online_mask, cpu_present_mask */
static DEFINE_MUTEX(cpu_add_remove_lock);
+bool cpuhp_tasks_frozen;
+EXPORT_SYMBOL_GPL(cpuhp_tasks_frozen);
/*
* The following two APIs (cpu_maps_update_begin/done) must be used when
@@ -207,27 +209,30 @@ int __register_cpu_notifier(struct notifier_block *nb)
return raw_notifier_chain_register(&cpu_chain, nb);
}
-static int __cpu_notify(unsigned long val, void *v, int nr_to_call,
+static int __cpu_notify(unsigned long val, unsigned int cpu, int nr_to_call,
int *nr_calls)
{
+ unsigned long mod = cpuhp_tasks_frozen ? CPU_TASKS_FROZEN : 0;
+ void *hcpu = (void *)(long)cpu;
+
int ret;
- ret = __raw_notifier_call_chain(&cpu_chain, val, v, nr_to_call,
+ ret = __raw_notifier_call_chain(&cpu_chain, val | mod, hcpu, nr_to_call,
nr_calls);
return notifier_to_errno(ret);
}
-static int cpu_notify(unsigned long val, void *v)
+static int cpu_notify(unsigned long val, unsigned int cpu)
{
- return __cpu_notify(val, v, -1, NULL);
+ return __cpu_notify(val, cpu, -1, NULL);
}
#ifdef CONFIG_HOTPLUG_CPU
-static void cpu_notify_nofail(unsigned long val, void *v)
+static void cpu_notify_nofail(unsigned long val, unsigned int cpu)
{
- BUG_ON(cpu_notify(val, v));
+ BUG_ON(cpu_notify(val, cpu));
}
EXPORT_SYMBOL(register_cpu_notifier);
EXPORT_SYMBOL(__register_cpu_notifier);
@@ -311,27 +316,21 @@ static inline void check_for_tasks(int dead_cpu)
read_unlock(&tasklist_lock);
}
-struct take_cpu_down_param {
- unsigned long mod;
- void *hcpu;
-};
-
/* Take this CPU down. */
static int take_cpu_down(void *_param)
{
- struct take_cpu_down_param *param = _param;
- int err;
+ int err, cpu = smp_processor_id();
/* Ensure this CPU doesn't handle any more interrupts. */
err = __cpu_disable();
if (err < 0)
return err;
- cpu_notify(CPU_DYING | param->mod, param->hcpu);
+ cpu_notify(CPU_DYING, cpu);
/* Give up timekeeping duties */
tick_handover_do_timer();
/* Park the stopper thread */
- stop_machine_park((long)param->hcpu);
+ stop_machine_park(cpu);
return 0;
}
@@ -339,12 +338,6 @@ static int take_cpu_down(void *_param)
static int _cpu_down(unsigned int cpu, int tasks_frozen)
{
int err, nr_calls = 0;
- void *hcpu = (void *)(long)cpu;
- unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0;
- struct take_cpu_down_param tcd_param = {
- .mod = mod,
- .hcpu = hcpu,
- };
if (num_online_cpus() == 1)
return -EBUSY;
@@ -354,10 +347,12 @@ static int _cpu_down(unsigned int cpu, int tasks_frozen)
cpu_hotplug_begin();
- err = __cpu_notify(CPU_DOWN_PREPARE | mod, hcpu, -1, &nr_calls);
+ cpuhp_tasks_frozen = tasks_frozen;
+
+ err = __cpu_notify(CPU_DOWN_PREPARE, cpu, -1, &nr_calls);
if (err) {
nr_calls--;
- __cpu_notify(CPU_DOWN_FAILED | mod, hcpu, nr_calls, NULL);
+ __cpu_notify(CPU_DOWN_FAILED, cpu, nr_calls, NULL);
pr_warn("%s: attempt to take down CPU %u failed\n",
__func__, cpu);
goto out_release;
@@ -389,10 +384,10 @@ static int _cpu_down(unsigned int cpu, int tasks_frozen)
/*
* So now all preempt/rcu users must observe !cpu_active().
*/
- err = stop_machine(take_cpu_down, &tcd_param, cpumask_of(cpu));
+ err = stop_machine(take_cpu_down, NULL, cpumask_of(cpu));
if (err) {
/* CPU didn't die: tell everyone. Can't complain. */
- cpu_notify_nofail(CPU_DOWN_FAILED | mod, hcpu);
+ cpu_notify_nofail(CPU_DOWN_FAILED, cpu);
irq_unlock_sparse();
goto out_release;
}
@@ -419,14 +414,14 @@ static int _cpu_down(unsigned int cpu, int tasks_frozen)
/* CPU is completely dead: tell everyone. Too late to complain. */
tick_cleanup_dead_cpu(cpu);
- cpu_notify_nofail(CPU_DEAD | mod, hcpu);
+ cpu_notify_nofail(CPU_DEAD, cpu);
check_for_tasks(cpu);
out_release:
cpu_hotplug_done();
if (!err)
- cpu_notify_nofail(CPU_POST_DEAD | mod, hcpu);
+ cpu_notify_nofail(CPU_POST_DEAD, cpu);
return err;
}
@@ -485,10 +480,8 @@ void smpboot_thread_init(void)
/* Requires cpu_add_remove_lock to be held */
static int _cpu_up(unsigned int cpu, int tasks_frozen)
{
- int ret, nr_calls = 0;
- void *hcpu = (void *)(long)cpu;
- unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0;
struct task_struct *idle;
+ int ret, nr_calls = 0;
cpu_hotplug_begin();
@@ -507,7 +500,9 @@ static int _cpu_up(unsigned int cpu, int tasks_frozen)
if (ret)
goto out;
- ret = __cpu_notify(CPU_UP_PREPARE | mod, hcpu, -1, &nr_calls);
+ cpuhp_tasks_frozen = tasks_frozen;
+
+ ret = __cpu_notify(CPU_UP_PREPARE, cpu, -1, &nr_calls);
if (ret) {
nr_calls--;
pr_warn("%s: attempt to bring up CPU %u failed\n",
@@ -523,11 +518,11 @@ static int _cpu_up(unsigned int cpu, int tasks_frozen)
BUG_ON(!cpu_online(cpu));
/* Now call notifier in preparation. */
- cpu_notify(CPU_ONLINE | mod, hcpu);
+ cpu_notify(CPU_ONLINE, cpu);
out_notify:
if (ret != 0)
- __cpu_notify(CPU_UP_CANCELED | mod, hcpu, nr_calls, NULL);
+ __cpu_notify(CPU_UP_CANCELED, cpu, nr_calls, NULL);
out:
cpu_hotplug_done();
@@ -719,13 +714,7 @@ core_initcall(cpu_hotplug_pm_sync_init);
*/
void notify_cpu_starting(unsigned int cpu)
{
- unsigned long val = CPU_STARTING;
-
-#ifdef CONFIG_PM_SLEEP_SMP
- if (frozen_cpus != NULL && cpumask_test_cpu(cpu, frozen_cpus))
- val = CPU_STARTING_FROZEN;
-#endif /* CONFIG_PM_SLEEP_SMP */
- cpu_notify(val, (void *)(long)cpu);
+ cpu_notify(CPU_STARTING, cpu);
}
#endif /* CONFIG_SMP */