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author | Ingo Molnar <mingo@elte.hu> | 2008-10-06 06:13:18 (GMT) |
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committer | Ingo Molnar <mingo@elte.hu> | 2008-10-06 06:13:18 (GMT) |
commit | 2c10c22af088ab5d94fae93ce3fe6436b2a208b4 (patch) | |
tree | db27721001f194327ddbdcd6c983c4ec68b77c00 /kernel/hrtimer.c | |
parent | f6121f4f8708195e88cbdf8dd8d171b226b3f858 (diff) | |
parent | fec6ed1d1f9b78a6acb4a3eb2c46c812ac2e96f0 (diff) | |
download | linux-fsl-qoriq-2c10c22af088ab5d94fae93ce3fe6436b2a208b4.tar.xz |
Merge branch 'linus' into sched/devel
Diffstat (limited to 'kernel/hrtimer.c')
-rw-r--r-- | kernel/hrtimer.c | 95 |
1 files changed, 85 insertions, 10 deletions
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index b8e4dce..cdec83e 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -672,13 +672,14 @@ static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer, */ BUG_ON(timer->function(timer) != HRTIMER_NORESTART); return 1; - case HRTIMER_CB_IRQSAFE_NO_SOFTIRQ: + case HRTIMER_CB_IRQSAFE_PERCPU: + case HRTIMER_CB_IRQSAFE_UNLOCKED: /* * This is solely for the sched tick emulation with * dynamic tick support to ensure that we do not * restart the tick right on the edge and end up with * the tick timer in the softirq ! The calling site - * takes care of this. + * takes care of this. Also used for hrtimer sleeper ! */ debug_hrtimer_deactivate(timer); return 1; @@ -1245,7 +1246,8 @@ static void __run_hrtimer(struct hrtimer *timer) timer_stats_account_hrtimer(timer); fn = timer->function; - if (timer->cb_mode == HRTIMER_CB_IRQSAFE_NO_SOFTIRQ) { + if (timer->cb_mode == HRTIMER_CB_IRQSAFE_PERCPU || + timer->cb_mode == HRTIMER_CB_IRQSAFE_UNLOCKED) { /* * Used for scheduler timers, avoid lock inversion with * rq->lock and tasklist_lock. @@ -1452,7 +1454,7 @@ void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, struct task_struct *task) sl->timer.function = hrtimer_wakeup; sl->task = task; #ifdef CONFIG_HIGH_RES_TIMERS - sl->timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ; + sl->timer.cb_mode = HRTIMER_CB_IRQSAFE_UNLOCKED; #endif } @@ -1591,29 +1593,95 @@ static void __cpuinit init_hrtimers_cpu(int cpu) #ifdef CONFIG_HOTPLUG_CPU -static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base, - struct hrtimer_clock_base *new_base) +static int migrate_hrtimer_list(struct hrtimer_clock_base *old_base, + struct hrtimer_clock_base *new_base, int dcpu) { struct hrtimer *timer; struct rb_node *node; + int raise = 0; while ((node = rb_first(&old_base->active))) { timer = rb_entry(node, struct hrtimer, node); BUG_ON(hrtimer_callback_running(timer)); debug_hrtimer_deactivate(timer); - __remove_hrtimer(timer, old_base, HRTIMER_STATE_INACTIVE, 0); + + /* + * Should not happen. Per CPU timers should be + * canceled _before_ the migration code is called + */ + if (timer->cb_mode == HRTIMER_CB_IRQSAFE_PERCPU) { + __remove_hrtimer(timer, old_base, + HRTIMER_STATE_INACTIVE, 0); + WARN(1, "hrtimer (%p %p)active but cpu %d dead\n", + timer, timer->function, dcpu); + continue; + } + + /* + * Mark it as STATE_MIGRATE not INACTIVE otherwise the + * timer could be seen as !active and just vanish away + * under us on another CPU + */ + __remove_hrtimer(timer, old_base, HRTIMER_STATE_MIGRATE, 0); timer->base = new_base; /* * Enqueue the timer. Allow reprogramming of the event device */ enqueue_hrtimer(timer, new_base, 1); + +#ifdef CONFIG_HIGH_RES_TIMERS + /* + * Happens with high res enabled when the timer was + * already expired and the callback mode is + * HRTIMER_CB_IRQSAFE_UNLOCKED (hrtimer_sleeper). The + * enqueue code does not move them to the soft irq + * pending list for performance/latency reasons, but + * in the migration state, we need to do that + * otherwise we end up with a stale timer. + */ + if (timer->state == HRTIMER_STATE_MIGRATE) { + timer->state = HRTIMER_STATE_PENDING; + list_add_tail(&timer->cb_entry, + &new_base->cpu_base->cb_pending); + raise = 1; + } +#endif + /* Clear the migration state bit */ + timer->state &= ~HRTIMER_STATE_MIGRATE; + } + return raise; +} + +#ifdef CONFIG_HIGH_RES_TIMERS +static int migrate_hrtimer_pending(struct hrtimer_cpu_base *old_base, + struct hrtimer_cpu_base *new_base) +{ + struct hrtimer *timer; + int raise = 0; + + while (!list_empty(&old_base->cb_pending)) { + timer = list_entry(old_base->cb_pending.next, + struct hrtimer, cb_entry); + + __remove_hrtimer(timer, timer->base, HRTIMER_STATE_PENDING, 0); + timer->base = &new_base->clock_base[timer->base->index]; + list_add_tail(&timer->cb_entry, &new_base->cb_pending); + raise = 1; } + return raise; +} +#else +static int migrate_hrtimer_pending(struct hrtimer_cpu_base *old_base, + struct hrtimer_cpu_base *new_base) +{ + return 0; } +#endif static void migrate_hrtimers(int cpu) { struct hrtimer_cpu_base *old_base, *new_base; - int i; + int i, raise = 0; BUG_ON(cpu_online(cpu)); old_base = &per_cpu(hrtimer_bases, cpu); @@ -1626,14 +1694,21 @@ static void migrate_hrtimers(int cpu) spin_lock_nested(&old_base->lock, SINGLE_DEPTH_NESTING); for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) { - migrate_hrtimer_list(&old_base->clock_base[i], - &new_base->clock_base[i]); + if (migrate_hrtimer_list(&old_base->clock_base[i], + &new_base->clock_base[i], cpu)) + raise = 1; } + if (migrate_hrtimer_pending(old_base, new_base)) + raise = 1; + spin_unlock(&old_base->lock); spin_unlock(&new_base->lock); local_irq_enable(); put_cpu_var(hrtimer_bases); + + if (raise) + hrtimer_raise_softirq(); } #endif /* CONFIG_HOTPLUG_CPU */ |