diff options
| author | Frederic Weisbecker <frederic@kernel.org> | 2024-02-25 23:55:07 +0100 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2024-02-26 11:37:32 +0100 |
| commit | 500f8f9bced86f0c0f2482773bd64a1b7ec9c4e1 (patch) | |
| tree | 16c613caa4c0ebacf748c44fee3dcd611b739118 /kernel/time/tick-sched.c | |
| parent | 3f69d04e146c6e14ccdd4e7b37d93f789229202a (diff) | |
| download | linux-500f8f9bced86f0c0f2482773bd64a1b7ec9c4e1.tar.gz | |
tick: Assume timekeeping is correctly handed over upon last offline idle call
The timekeeping duty is handed over from the outgoing CPU on stop
machine, then the oneshot tick is stopped right after. Therefore it's
guaranteed that the current CPU isn't the timekeeper upon its last call
to idle.
Besides, calling tick_nohz_idle_stop_tick() while the dying CPU goes
into idle suggests that the tick is going to be stopped while it is
actually stopped already from the appropriate CPU hotplug state.
Remove the confusing call and the obsolete case handling and convert it
to a sanity check that verifies the above assumption.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240225225508.11587-16-frederic@kernel.org
Diffstat (limited to 'kernel/time/tick-sched.c')
| -rw-r--r-- | kernel/time/tick-sched.c | 13 |
1 files changed, 1 insertions, 12 deletions
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 89d16b8ea2c4fc..269e21590df536 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -1160,18 +1160,7 @@ static bool report_idle_softirq(void) static bool can_stop_idle_tick(int cpu, struct tick_sched *ts) { - /* - * If this CPU is offline and it is the one which updates - * jiffies, then give up the assignment and let it be taken by - * the CPU which runs the tick timer next. If we don't drop - * this here, the jiffies might be stale and do_timer() never - * gets invoked. - */ - if (unlikely(!cpu_online(cpu))) { - if (cpu == tick_do_timer_cpu) - tick_do_timer_cpu = TICK_DO_TIMER_NONE; - return false; - } + WARN_ON_ONCE(cpu_is_offline(cpu)); if (unlikely(!tick_sched_flag_test(ts, TS_FLAG_NOHZ))) return false; |