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After re-online, a later next_expiry recalc can treat those empty buckets as pending and temporarily pull next_expiry forward until collect drains the bits. Clear pending_map under the base lock after migration in timers_dead_cpu(), and in timers_prepare_cpu() for a full base reinit. Signed-off-by: Liang Hao --- kernel/time/timer.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/time/timer.c b/kernel/time/timer.c index ae9abf14688e..e550489c73b8 100644 --- a/kernel/time/timer.c +++ b/kernel/time/timer.c @@ -44,6 +44,7 @@ #include #include #include +#include #include #include @@ -2509,6 +2510,7 @@ int timers_prepare_cpu(unsigned int cpu) base->next_expiry_recalc = false; base->timers_pending = false; base->is_idle = false; + bitmap_zero(base->pending_map, WHEEL_SIZE); } return 0; } @@ -2541,6 +2543,7 @@ int timers_dead_cpu(unsigned int cpu) for (i = 0; i < WHEEL_SIZE; i++) migrate_timer_list(new_base, old_base->vectors + i); + bitmap_zero(old_base->pending_map, WHEEL_SIZE); raw_spin_unlock(&old_base->lock); raw_spin_unlock_irq(&new_base->lock); put_cpu_ptr(&timer_bases); -- 2.50.1 (Apple Git-155)