Commit 7ff15cd0 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

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

Pull timer fixes from Ingo Molnar:
 "Three fixes: fix link failure on Alpha, fix a Sparse warning and
  annotate/robustify a lockless access in the NOHZ code"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tick/sched: Annotate lockless access to last_jiffies_update
  lib/vdso: Make __cvdso_clock_getres() static
  time/posix-stubs: Provide compat itimer supoprt for alpha
parents 9e79c523 de95a991

kernel/time/posix-stubs.c

+3 −0
Original line number Diff line number Diff line
@@ -151,6 +151,9 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags, 


#ifdef CONFIG_COMPAT

COMPAT_SYS_NI(timer_create);

#endif



#if defined(CONFIG_COMPAT) || defined(CONFIG_ALPHA)

COMPAT_SYS_NI(getitimer);

COMPAT_SYS_NI(setitimer);

#endif

kernel/time/tick-sched.c

+9 −5
Original line number Diff line number Diff line
@@ -58,8 +58,9 @@ static void tick_do_update_jiffies64(ktime_t now) 


	/*

	 * Do a quick check without holding jiffies_lock:

	 * The READ_ONCE() pairs with two updates done later in this function.

	 */

	delta = ktime_sub(now, last_jiffies_update);

	delta = ktime_sub(now, READ_ONCE(last_jiffies_update));

	if (delta < tick_period)

		return;
@@ -70,8 +71,9 @@ static void tick_do_update_jiffies64(ktime_t now) 
	if (delta >= tick_period) {



		delta = ktime_sub(delta, tick_period);

		last_jiffies_update = ktime_add(last_jiffies_update,

						tick_period);

		/* Pairs with the lockless read in this function. */

		WRITE_ONCE(last_jiffies_update,

			   ktime_add(last_jiffies_update, tick_period));



		/* Slow path for long timeouts */

		if (unlikely(delta >= tick_period)) {
@@ -79,8 +81,10 @@ static void tick_do_update_jiffies64(ktime_t now) 


			ticks = ktime_divns(delta, incr);



			last_jiffies_update = ktime_add_ns(last_jiffies_update,

							   incr * ticks);

			/* Pairs with the lockless read in this function. */

			WRITE_ONCE(last_jiffies_update,

				   ktime_add_ns(last_jiffies_update,

						incr * ticks));

		}

		do_timer(++ticks);

lib/vdso/gettimeofday.c

+1 −0
Original line number Diff line number Diff line
@@ -221,6 +221,7 @@ int __cvdso_clock_getres_common(clockid_t clock, struct __kernel_timespec *res) 
	return 0;

}



static __maybe_unused

int __cvdso_clock_getres(clockid_t clock, struct __kernel_timespec *res)

{

	int ret = __cvdso_clock_getres_common(clock, res);

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