Commit a115d5ca authored Oct 16, 2007 by Ingo Molnar Committed by Linus Torvalds Oct 17, 2007

fix the softlockup watchdog to actually work



this Xen related commit:

   commit 966812dc
   Author: Jeremy Fitzhardinge <jeremy@goop.org>
   Date:   Tue May 8 00:28:02 2007 -0700

       Ignore stolen time in the softlockup watchdog

broke the softlockup watchdog to never report any lockups. (!)

print_timestamp defaults to 0, this makes the following condition
always true:

	if (print_timestamp < (touch_timestamp + 1) ||

and we'll in essence never report soft lockups.

apparently the functionality of the soft lockup watchdog was never
actually tested with that patch applied ...

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent a3b13c23

kernel/softlockup.c

+4 −3

Original line number	Diff line number	Diff line
		@@ -82,10 +82,11 @@ void softlockup_tick(void)
		print_timestamp = per_cpu(print_timestamp, this_cpu);

		/* report at most once a second */
		if (print_timestamp < (touch_timestamp + 1) \|\|
		did_panic \|\|
		!per_cpu(watchdog_task, this_cpu))
		if ((print_timestamp >= touch_timestamp &&
		print_timestamp < (touch_timestamp + 1)) \|\|
		did_panic \|\| !per_cpu(watchdog_task, this_cpu)) {
		return;
		}

		/* do not print during early bootup: */
		if (unlikely(system_state != SYSTEM_RUNNING)) {

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