diff options
Diffstat (limited to 'kernel/time')
| -rw-r--r-- | kernel/time/hrtimer.c | 35 |
1 files changed, 33 insertions, 2 deletions
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index c8af165c04eb..5d44c90d41ea 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -882,11 +882,42 @@ static void hrtimer_reprogram(struct hrtimer *timer, bool reprogram) */ void clock_was_set(unsigned int bases) { + cpumask_var_t mask; + int cpu; + if (!hrtimer_hres_active() && !tick_nohz_active) goto out_timerfd; - /* Retrigger the CPU local events everywhere */ - on_each_cpu(retrigger_next_event, NULL, 1); + if (!zalloc_cpumask_var(&mask, GFP_KERNEL)) { + on_each_cpu(retrigger_next_event, NULL, 1); + goto out_timerfd; + } + + /* Avoid interrupting CPUs if possible */ + cpus_read_lock(); + for_each_online_cpu(cpu) { + struct hrtimer_cpu_base *cpu_base = &per_cpu(hrtimer_bases, cpu); + unsigned long flags; + + raw_spin_lock_irqsave(&cpu_base->lock, flags); + /* + * Only send the IPI when there are timers queued in one of + * the affected clock bases. Otherwise update the base + * remote to ensure that the next enqueue of a timer on + * such a clock base will see the correct offsets. + */ + if (cpu_base->active_bases & bases) + cpumask_set_cpu(cpu, mask); + else + hrtimer_update_base(cpu_base); + raw_spin_unlock_irqrestore(&cpu_base->lock, flags); + } + + preempt_disable(); + smp_call_function_many(mask, retrigger_next_event, NULL, 1); + preempt_enable(); + cpus_read_unlock(); + free_cpumask_var(mask); out_timerfd: timerfd_clock_was_set(); |