Re: [Regression] 2.6.24-git3: Major annoyance duringsuspend/hibernation on x86-64 (bisected)

From: Ingo Molnar
Date: Fri Feb 01 2008 - 17:49:41 EST



* Dmitry Adamushko <dmitry.adamushko@xxxxxxxxx> wrote:

> > I've observed delays from ~3 s. up to ~8 s. (out of ~20 tests) so
> > the 10s. delay of msleep_interruptible() might be related but I'm
> > still looking for the reason why this fix helps (and what goes wrong
> > with the current code).
>
> heh... it's pretty obvious indeed. What's msleep_interruptible() is
> all about? :-)
>
> "sleep waiting for signals"
>
> so the 'watchdog' thread gets woken up
>
> [ as a result of cpu_callback(action = CPU_DEAD) --> kthread_stop() ]
>
> just to be immediately scheduled out again for as long as the
> remaining timeout > 0.
>
> So it should work if we substitute msleep_interruptible() with
> schedule_timeout_interruptible().

Doh. Could someone with ths problem please test the patch below, does it
do the trick?

Ingo

---
kernel/softlockup.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux/kernel/softlockup.c
===================================================================
--- linux.orig/kernel/softlockup.c
+++ linux/kernel/softlockup.c
@@ -228,7 +228,7 @@ static int watchdog(void *__bind_cpu)
*/
while (!kthread_should_stop()) {
touch_softlockup_watchdog();
- msleep_interruptible(10000);
+ schedule_timeout_interruptible(10*HZ);

if (this_cpu != check_cpu)
continue;
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/