Re: broken suspend (sched related) [Was: 2.6.24-rc4-mm1]

Ingo Molnar
2007-12-07T17:54:44Z

* Ingo Molnar <mingo@elte.hu> wrote:

> thanks for tracking it down. Does the patch below help?

oops, that should be the patch below. Otherwise the watchdog kernel
threads will just loop around.

Ingo

---
kernel/softlockup.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

Index: linux/kernel/softlockup.c
===================================================================
--- linux.orig/kernel/softlockup.c
+++ linux/kernel/softlockup.c
@@ -101,7 +101,11 @@ void softlockup_tick(void)

now = get_timestamp(this_cpu);

- /* Warn about unreasonable delays: */
+ /* Wake up the high-prio watchdog task every second: */
+ if (now > (touch_timestamp + 1))
+ wake_up_process(per_cpu(watchdog_task, this_cpu));
+
+ /* Warn about unreasonable 10+ seconds delays: */
if (now <= (touch_timestamp + softlockup_thresh))
return;

@@ -213,8 +217,9 @@ static int watchdog(void *__bind_cpu)
* debug-printout triggers in softlockup_tick().
*/
while (!kthread_should_stop()) {
+ set_current_state(TASK_INTERRUPTIBLE);
touch_softlockup_watchdog();
- msleep_interruptible(10000);
+ schedule();

/*
* Only do the hung-tasks check on one CPU: