From: Jason Low Date: Fri, 13 Feb 2015 03:58:07 +0000 (+0800) Subject: cpuset: Fix cpuset sched_relax_domain_level X-Git-Tag: v3.16.35~2538 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=6efeedf20e30cb92ffff038bb2994c0225c969ad;p=thirdparty%2Fkernel%2Fstable.git cpuset: Fix cpuset sched_relax_domain_level commit 283cb41f426b723a0255702b761b0fc5d1b53a81 upstream. The cpuset.sched_relax_domain_level can control how far we do immediate load balancing on a system. However, it was found on recent kernels that echo'ing a value into cpuset.sched_relax_domain_level did not reduce any immediate load balancing. The reason this occurred was because the update_domain_attr_tree() traversal did not update for the "top_cpuset". This resulted in nothing being changed when modifying the sched_relax_domain_level parameter. This patch is able to address that problem by having update_domain_attr_tree() allow updates for the root in the cpuset traversal. Fixes: fc560a26acce ("cpuset: replace cpuset->stack_list with cpuset_for_each_descendant_pre()") Signed-off-by: Jason Low Signed-off-by: Zefan Li Signed-off-by: Tejun Heo Tested-by: Serge Hallyn Signed-off-by: Luis Henriques --- diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 116a4164720a0..524a8eef29655 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -503,9 +503,6 @@ static void update_domain_attr_tree(struct sched_domain_attr *dattr, rcu_read_lock(); cpuset_for_each_descendant_pre(cp, pos_css, root_cs) { - if (cp == root_cs) - continue; - /* skip the whole subtree if @cp doesn't have any CPU */ if (cpumask_empty(cp->cpus_allowed)) { pos_css = css_rightmost_descendant(pos_css);