Cpusets would be using timer migration code to isolate/quiese a CPU. And hence that should be changed a bit as the CPU in question would be online now. Also we need to make sure that we don't remove pinned timers.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- kernel/timer.c | 54 +++++++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 43 insertions(+), 11 deletions(-)
diff --git a/kernel/timer.c b/kernel/timer.c index a7f8b99..81d64e0 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -1602,18 +1602,27 @@ static int init_timers_cpu(int cpu) return 0; }
-#ifdef CONFIG_HOTPLUG_CPU -static void migrate_timer_list(struct tvec_base *new_base, struct list_head *head) +#if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_CPUSETS) +static void migrate_timer_list(struct tvec_base *new_base, + struct list_head *head, bool remove_pinned) { struct timer_list *timer; + struct list_head pinned_list; int is_pinned;
+ INIT_LIST_HEAD(&pinned_list); + while (!list_empty(head)) { timer = list_first_entry(head, struct timer_list, entry); - /* We ignore the accounting on the dying cpu */ - detach_timer(timer, false);
is_pinned = tbase_get_pinned(timer->base); + if (!remove_pinned && is_pinned) { + list_move_tail(&timer->entry, &pinned_list); + continue; + } else { + /* We ignore the accounting on the dying cpu */ + detach_timer(timer, false); + }
/* Check if CPU still has pinned timers */ if (is_pinned) { @@ -1625,15 +1634,18 @@ static void migrate_timer_list(struct tvec_base *new_base, struct list_head *hea timer_set_base(timer, new_base); internal_add_timer(new_base, timer); } + + if (!list_empty(&pinned_list)) + list_splice_tail(&pinned_list, head); }
-static void migrate_timers(int cpu) +/* Migrate timers from 'cpu' to this_cpu */ +static void __migrate_timers(int cpu, bool remove_pinned) { struct tvec_base *old_base; struct tvec_base *new_base; int i;
- BUG_ON(cpu_online(cpu)); old_base = per_cpu(tvec_bases, cpu); new_base = get_cpu_var(tvec_bases); /* @@ -1646,20 +1658,40 @@ static void migrate_timers(int cpu) BUG_ON(old_base->running_timer);
for (i = 0; i < TVR_SIZE; i++) - migrate_timer_list(new_base, old_base->tv1.vec + i); + migrate_timer_list(new_base, old_base->tv1.vec + i, + remove_pinned); for (i = 0; i < TVN_SIZE; i++) { - migrate_timer_list(new_base, old_base->tv2.vec + i); - migrate_timer_list(new_base, old_base->tv3.vec + i); - migrate_timer_list(new_base, old_base->tv4.vec + i); - migrate_timer_list(new_base, old_base->tv5.vec + i); + migrate_timer_list(new_base, old_base->tv2.vec + i, + remove_pinned); + migrate_timer_list(new_base, old_base->tv3.vec + i, + remove_pinned); + migrate_timer_list(new_base, old_base->tv4.vec + i, + remove_pinned); + migrate_timer_list(new_base, old_base->tv5.vec + i, + remove_pinned); }
spin_unlock(&old_base->lock); spin_unlock_irq(&new_base->lock); put_cpu_var(tvec_bases); } +#endif /* CONFIG_HOTPLUG_CPU || CONFIG_CPUSETS */ + +#ifdef CONFIG_HOTPLUG_CPU +static void migrate_timers(int cpu) +{ + BUG_ON(cpu_online(cpu)); + __migrate_timers(cpu, true); +} #endif /* CONFIG_HOTPLUG_CPU */
+#ifdef CONFIG_CPUSETS +void timer_quiesce_cpu(void *data) +{ + __migrate_timers((int)data, false); +} +#endif /* CONFIG_CPUSETS */ + static int timer_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu) {