Messages in this thread Patch in this message | | | Date | Wed, 28 Nov 2007 13:56:37 +0100 | From | Ingo Molnar <> | Subject | [patch] softlockup: fix false positives on CONFIG_NOHZ |
| |
* Ingo Molnar <mingo@elte.hu> wrote:
> these can be fixed, but: > > > This will introduce an up-to-one-second delay in responding to > > kthread_should_stop(). Is that bad? > > grumble, it's bad. I guess David is right that this should be fixed > the right way ;-) So the above patch cannot go in.
Thomas found the right fix. David, could you try the fix below, does it fix those false positives on your nohz Niagara cores?
Ingo
----------------> Subject: softlockup: fix false positives on CONFIG_NOHZ From: Thomas Gleixner <tglx@linutronix.de>
David Miller reported soft lockup false-positives that trigger on NOHZ due to CPUs idling for more than 10 seconds.
The solution is touch the softlockup watchdog when we return from idle. (by definition we are not 'locked up' when we were idle)
http://bugzilla.kernel.org/show_bug.cgi?id=9409
Reported-by: David Miller <davem@davemloft.net> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> --- kernel/time/tick-sched.c | 2 ++ 1 file changed, 2 insertions(+)
Index: linux/kernel/time/tick-sched.c =================================================================== --- linux.orig/kernel/time/tick-sched.c +++ linux/kernel/time/tick-sched.c @@ -133,6 +133,8 @@ void tick_nohz_update_jiffies(void) if (!ts->tick_stopped) return; + touch_softlockup_watchdog(); + cpu_clear(cpu, nohz_cpu_mask); now = ktime_get(); - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |