From e17224bf1d01b461ec02a60f5a9b7657a89bdd23 Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Sat, 10 Sep 2005 00:26:18 -0700 Subject: [PATCH] [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-format-patch failed