softlockup: Stop spurious softlockup messages due to overflow

commit 8c2eb4805d upstream.

Ensure additions on touch_ts do not overflow.  This can occur
when the top 32 bits of the TSC reach 0xffffffff causing
additions to touch_ts to overflow and this in turn generates
spurious softlockup warnings.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
LKML-Reference: <1268994482.1798.6.camel@lenovo>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Colin Ian King 2010-03-19 10:28:02 +00:00 committed by Greg Kroah-Hartman
parent 893b328f07
commit 7b6c1753bc

View File

@ -140,11 +140,11 @@ void softlockup_tick(void)
* Wake up the high-prio watchdog task twice per
* threshold timespan.
*/
if (now > touch_timestamp + softlockup_thresh/2)
if (time_after(now - softlockup_thresh/2, touch_timestamp))
wake_up_process(per_cpu(watchdog_task, this_cpu));
/* Warn about unreasonable delays: */
if (now <= (touch_timestamp + softlockup_thresh))
if (time_before_eq(now - softlockup_thresh, touch_timestamp))
return;
per_cpu(print_timestamp, this_cpu) = touch_timestamp;