Commit 2f3672cb authored Aug 05, 2018 by Linus Torvalds

Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer fixes from Thomas Gleixner:
 "Two oneliners addressing NOHZ failures:

   - Use a bitmask to check for the pending timer softirq and not the
     bit number. The existing code using the bit number checked for
     the wrong bit, which caused timers to either expire late or stop
     completely.

   - Make the nohz evaluation on interrupt exit more robust. The
     existing code did not re-arm the hardware when interrupting a
     running softirq in task context (ksoftirqd or tail of
     local_bh_enable()), which caused timers to either expire late
     or stop completely"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  nohz: Fix missing tick reprogram when interrupting an inline softirq
  nohz: Fix local_timer_softirq_pending()

parents 0cdf6d46 0a0e0829

kernel/softirq.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -390,7 +390,7 @@ static inline void tick_irq_exit(void)

		/* Make sure that timer wheel updates are propagated */
		if ((idle_cpu(cpu) && !need_resched()) \|\| tick_nohz_full_cpu(cpu)) {
		if (!in_interrupt())
		if (!in_irq())
		tick_nohz_irq_exit();
		}
		#endif

kernel/time/tick-sched.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -642,7 +642,7 @@ static void tick_nohz_restart(struct tick_sched *ts, ktime_t now)

		static inline bool local_timer_softirq_pending(void)
		{
		return local_softirq_pending() & TIMER_SOFTIRQ;
		return local_softirq_pending() & BIT(TIMER_SOFTIRQ);
		}

		static ktime_t tick_nohz_next_event(struct tick_sched *ts, int cpu)

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