Re: 2.6.20-rc6-mm3

From: Ingo Molnar
Date: Thu Feb 01 2007 - 14:06:41 EST



* Mattia Dongili <malattia@xxxxxxxx> wrote:

> > Full dmesg and config:
> > http://oioio.altervista.org/linux/nohz_soft-lockup.dmesg
> > http://oioio.altervista.org/linux/config-2.6.20-rc6-mm3-1
> >
> > As a side note the process becomes slower and slower as it proceeds,
> > it's definitely noticeable during my iptables rules setup (nothing
> > that complex, just default policies and subnet/lan accept rules).
> > Building with NO_HZ=n right now.
>
> yes, slowness is gone. Any useful information I can provide?

thanks for reporting this - i'll try your config. There's one fix ontop
of -mm3 - see below - but i'm not sure it's related, it addresses resume
problems.

Ingo

---
kernel/timer.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

Index: linux/kernel/timer.c
===================================================================
--- linux.orig/kernel/timer.c
+++ linux/kernel/timer.c
@@ -1120,8 +1120,9 @@ static int timekeeping_resume(struct sys

if (now && (now > timekeeping_suspend_time)) {
unsigned long sleep_length = now - timekeeping_suspend_time;
+
xtime.tv_sec += sleep_length;
- jiffies_64 += (u64)sleep_length * HZ;
+ wall_to_monotonic.tv_sec -= sleep_length;
}
/* re-base the last cycle value */
clock->cycle_last = clocksource_read(clock);
@@ -1130,7 +1131,7 @@ static int timekeeping_resume(struct sys
warp_check_clock_was_changed();
write_sequnlock_irqrestore(&xtime_lock, flags);

- clockevents_notify(CLOCK_EVT_NOTIFY_RESUME, NULL);
+ touch_softlockup_watchdog();
/* Resume hrtimers */
clock_was_set();

-
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/