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Diffstat (limited to 'kernel/cpu.c')
-rw-r--r--kernel/cpu.c43
1 files changed, 39 insertions, 4 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 1972b161c61e..94bbe4695232 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -20,6 +20,7 @@
#include <linux/gfp.h>
#include <linux/suspend.h>
#include <linux/lockdep.h>
+#include <linux/tick.h>
#include <trace/events/power.h>
#include "smpboot.h"
@@ -338,6 +339,8 @@ static int __ref take_cpu_down(void *_param)
return err;
cpu_notify(CPU_DYING | param->mod, param->hcpu);
+ /* Give up timekeeping duties */
+ tick_handover_do_timer();
/* Park the stopper thread */
kthread_park(current);
return 0;
@@ -408,13 +411,17 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
*
* Wait for the stop thread to go away.
*/
- while (!idle_cpu(cpu))
+ while (!per_cpu(cpu_dead_idle, cpu))
cpu_relax();
+ smp_mb(); /* Read from cpu_dead_idle before __cpu_die(). */
+ per_cpu(cpu_dead_idle, cpu) = false;
+ hotplug_cpu__broadcast_tick_pull(cpu);
/* This actually kills the CPU. */
__cpu_die(cpu);
/* CPU is completely dead: tell everyone. Too late to complain. */
+ tick_cleanup_dead_cpu(cpu);
cpu_notify_nofail(CPU_DEAD | mod, hcpu);
check_for_tasks(cpu);
@@ -446,6 +453,37 @@ out:
EXPORT_SYMBOL(cpu_down);
#endif /*CONFIG_HOTPLUG_CPU*/
+/*
+ * Unpark per-CPU smpboot kthreads at CPU-online time.
+ */
+static int smpboot_thread_call(struct notifier_block *nfb,
+ unsigned long action, void *hcpu)
+{
+ int cpu = (long)hcpu;
+
+ switch (action & ~CPU_TASKS_FROZEN) {
+
+ case CPU_ONLINE:
+ smpboot_unpark_threads(cpu);
+ break;
+
+ default:
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block smpboot_thread_notifier = {
+ .notifier_call = smpboot_thread_call,
+ .priority = CPU_PRI_SMPBOOT,
+};
+
+void __cpuinit smpboot_thread_init(void)
+{
+ register_cpu_notifier(&smpboot_thread_notifier);
+}
+
/* Requires cpu_add_remove_lock to be held */
static int _cpu_up(unsigned int cpu, int tasks_frozen)
{
@@ -485,9 +523,6 @@ static int _cpu_up(unsigned int cpu, int tasks_frozen)
goto out_notify;
BUG_ON(!cpu_online(cpu));
- /* Wake the per cpu threads */
- smpboot_unpark_threads(cpu);
-
/* Now call notifier in preparation. */
cpu_notify(CPU_ONLINE | mod, hcpu);