lkml.org 
[lkml]   [2008]   [Jan]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: CONFIG_NO_HZ breaks blktrace timestamps

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

> > With those patches, CONFIG_NO_HZ works just fine.
>
> could you please try the two patches below, do they fix the problem as
> well? They got a ton of testing in x86.git in the past ~2 months and
> we could perhaps still push them into v2.6.24.

plus, if needed, perhaps this patch below from Guillaume ontop of it.

Ingo

---------------->
Subject: sched: fix rq->clock warps on frequency changes
From: Guillaume Chazarain <guichaz@yahoo.fr>

sched: fix rq->clock warps on frequency changes

Fix 2bacec8c318ca0418c0ee9ac662ee44207765dd4
(sched: touch softlockup watchdog after idling) that reintroduced warps
on frequency changes. touch_softlockup_watchdog() calls __update_rq_clock
that checks rq->clock for warps, so call it after adjusting rq->clock.

Signed-off-by: Guillaume Chazarain <guichaz@yahoo.fr>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
kernel/sched.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux-x86.q/kernel/sched.c
===================================================================
--- linux-x86.q.orig/kernel/sched.c
+++ linux-x86.q/kernel/sched.c
@@ -668,7 +668,6 @@ void sched_clock_idle_wakeup_event(u64 d
struct rq *rq = cpu_rq(smp_processor_id());
u64 now = sched_clock();

- touch_softlockup_watchdog();
rq->idle_clock += delta_ns;
/*
* Override the previous timestamp and ignore all
@@ -680,6 +679,7 @@ void sched_clock_idle_wakeup_event(u64 d
rq->prev_clock_raw = now;
rq->clock += delta_ns;
spin_unlock(&rq->lock);
+ touch_softlockup_watchdog();
}
EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event);


\
 
 \ /
  Last update: 2008-01-11 10:55    [W:0.078 / U:1.376 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site