From: Nick Piggin Date: Sat, 10 Sep 2005 07:26:18 +0000 (-0700) Subject: [PATCH] sched: less locking X-Git-Tag: v2.6.14-rc1~214 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e17224bf1d01b461ec02a60f5a9b7657a89bdd23;p=pandora-kernel.git [PATCH] sched: less locking During periodic load balancing, don't hold this runqueue's lock while scanning remote runqueues, which can take a non trivial amount of time especially on very large systems. Holding the runqueue lock will only help to stabilise ->nr_running, however this doesn't do much to help because tasks being woken will simply get held up on the runqueue lock, so ->nr_running would not provide a really accurate picture of runqueue load in that case anyway. What's more, ->nr_running (and possibly the cpu_load averages) of remote runqueues won't be stable anyway, so load balancing is always an inexact operation. Signed-off-by: Nick Piggin Acked-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Reading git-diff-tree failed