lkml.org 
[lkml]   [2006]   [Mar]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Subject[2.6.16-mm1 patch] ignore timewarps
From
Date
Greetings,

The patch below is a correction to patch 1 of my throttling tree series.

The only thing that really matters is that timewarps are ignored,
whatever the cause. This patch does that, and only that.

-Mike

Signed-off-by: Mike Galbraith <efault@gmx.de>

--- linux-2.6.16-mm1/kernel/sched.c.org 2006-03-23 15:01:41.000000000 +0100
+++ linux-2.6.16-mm1/kernel/sched.c 2006-03-23 15:02:25.000000000 +0100
@@ -805,6 +805,15 @@
unsigned long long __sleep_time = now - p->timestamp;
unsigned long sleep_time;

+ /*
+ * On SMP systems, a task can go to sleep on one CPU
+ * and wake up on another. When this happens, now can
+ * end up being less than p->timestamp for short sleeps.
+ * Ignore these, they're insignificant.
+ */
+ if (unlikely(now < p->timestamp))
+ __sleep_time = 0;
+
if (batch_task(p))
sleep_time = 0;
else {

-
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/

\
 
 \ /
  Last update: 2006-03-25 07:20    [from the cache]
©2003-2014 Jasper Spaans. hosted at Digital Ocean