diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/time/hrtimer.c | 18 |
1 files changed, 13 insertions, 5 deletions
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index 9c320ab7a944..697816d0dc26 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -1786,13 +1786,21 @@ EXPORT_SYMBOL_GPL(__hrtimer_get_remaining); ktime_t hrtimer_get_next_event(void) { struct hrtimer_cpu_base *cpu_base = this_cpu_ptr(&hrtimer_bases); - ktime_t expires = KTIME_MAX; - guard(raw_spinlock_irqsave)(&cpu_base->lock); - if (!hrtimer_hres_active(cpu_base)) - expires = __hrtimer_get_next_event(cpu_base, HRTIMER_ACTIVE_ALL); + /* + * When HRES is active cmp_next_hrtimer_event() expects KTIME_MAX. + * + * cpu_base->hres_active is written only by the local CPU in + * hrtimer_switch_to_hres() from hard interrupt context and in + * hrtimers_cpu_starting() during CPU bring-up, and all callers reach + * this with interrupts disabled on the same CPU, so an unlocked read is + * stable without holding the lock. + */ + if (hrtimer_hres_active(cpu_base)) + return KTIME_MAX; - return expires; + guard(raw_spinlock_irqsave)(&cpu_base->lock); + return __hrtimer_get_next_event(cpu_base, HRTIMER_ACTIVE_ALL); } /** |