Commit fbb9c58e authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'timers-urgent-2022-04-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull timer fixes from Thomas Gleixner:
 "A small set of fixes for the timers core:

   - Fix the warning condition in __run_timers() which does not take
     into account that a CPU base (especially the deferrable base) never
     has a timer armed on it and therefore the next_expiry value can
     become stale.

   - Replace a WARN_ON() in the NOHZ code with a WARN_ON_ONCE() to
     prevent endless spam in dmesg.

   - Remove the double star from a comment which is not meant to be in
     kernel-doc format"

* tag 'timers-urgent-2022-04-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tick/sched: Fix non-kernel-doc comment
  tick/nohz: Use WARN_ON_ONCE() to prevent console saturation
  timers: Fix warning condition in __run_timers()
parents 0e59732e 9c95bc25

kernel/time/tick-sched.c

+3 −3
Original line number Diff line number Diff line
@@ -188,7 +188,7 @@ static void tick_sched_do_timer(struct tick_sched *ts, ktime_t now) 
	 */

	if (unlikely(tick_do_timer_cpu == TICK_DO_TIMER_NONE)) {

#ifdef CONFIG_NO_HZ_FULL

		WARN_ON(tick_nohz_full_running);

		WARN_ON_ONCE(tick_nohz_full_running);

#endif

		tick_do_timer_cpu = cpu;

	}
@@ -1538,7 +1538,7 @@ void tick_cancel_sched_timer(int cpu) 
}

#endif



/**

/*

 * Async notification about clocksource changes

 */

void tick_clock_notify(void)
@@ -1559,7 +1559,7 @@ void tick_oneshot_notify(void) 
	set_bit(0, &ts->check_clocks);

}



/**

/*

 * Check, if a change happened, which makes oneshot possible.

 *

 * Called cyclic from the hrtimer softirq (driven by the timer

kernel/time/timer.c

+7 −4
Original line number Diff line number Diff line
@@ -1722,11 +1722,14 @@ static inline void __run_timers(struct timer_base *base) 
	       time_after_eq(jiffies, base->next_expiry)) {

		levels = collect_expired_timers(base, heads);

		/*

		 * The only possible reason for not finding any expired

		 * timer at this clk is that all matching timers have been

		 * dequeued.

		 */

		WARN_ON_ONCE(!levels && !base->next_expiry_recalc);

		 * The two possible reasons for not finding any expired

		 * timer at this clk are that all matching timers have been

		 * dequeued or no timer has been queued since

		 * base::next_expiry was set to base::clk +

		 * NEXT_TIMER_MAX_DELTA.

		 */

		WARN_ON_ONCE(!levels && !base->next_expiry_recalc

			     && base->timers_pending);

		base->clk++;

		base->next_expiry = __next_timer_interrupt(base);