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authorLai Jiangshan <laijs@cn.fujitsu.com>2008-07-29 22:33:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-07-30 09:41:44 -0700
commitf5393693e96393131a4a2e2743f883986d508503 (patch)
tree91c6b0687939b9361c8cdcebb05494f1d0524f72 /kernel/cpuset.c
parent8d1e6266f512b3a94ef6d33528ff385f1aea0392 (diff)
downloadlinux-f5393693e96393131a4a2e2743f883986d508503.tar.bz2
cpuset: speed up sched domain partition
All child cpusets contain a subset of the parent's cpus, so we can skip them when partitioning sched domains. This decreases 'csa' greately for cpusets with multi-level hierarchy. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Paul Menage <menage@google.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Reviewed-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/cpuset.c')
-rw-r--r--kernel/cpuset.c41
1 files changed, 37 insertions, 4 deletions
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 3624dc0e95ed..c818c36b0c5f 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -486,13 +486,38 @@ static int cpusets_overlap(struct cpuset *a, struct cpuset *b)
static void
update_domain_attr(struct sched_domain_attr *dattr, struct cpuset *c)
{
- if (!dattr)
- return;
if (dattr->relax_domain_level < c->relax_domain_level)
dattr->relax_domain_level = c->relax_domain_level;
return;
}
+static void
+update_domain_attr_tree(struct sched_domain_attr *dattr, struct cpuset *c)
+{
+ LIST_HEAD(q);
+
+ list_add(&c->stack_list, &q);
+ while (!list_empty(&q)) {
+ struct cpuset *cp;
+ struct cgroup *cont;
+ struct cpuset *child;
+
+ cp = list_first_entry(&q, struct cpuset, stack_list);
+ list_del(q.next);
+
+ if (cpus_empty(cp->cpus_allowed))
+ continue;
+
+ if (is_sched_load_balance(cp))
+ update_domain_attr(dattr, cp);
+
+ list_for_each_entry(cont, &cp->css.cgroup->children, sibling) {
+ child = cgroup_cs(cont);
+ list_add_tail(&child->stack_list, &q);
+ }
+ }
+}
+
/*
* rebuild_sched_domains()
*
@@ -614,8 +639,16 @@ void rebuild_sched_domains(void)
if (cpus_empty(cp->cpus_allowed))
continue;
- if (is_sched_load_balance(cp))
+ /*
+ * All child cpusets contain a subset of the parent's cpus, so
+ * just skip them, and then we call update_domain_attr_tree()
+ * to calc relax_domain_level of the corresponding sched
+ * domain.
+ */
+ if (is_sched_load_balance(cp)) {
csa[csn++] = cp;
+ continue;
+ }
list_for_each_entry(cont, &cp->css.cgroup->children, sibling) {
child = cgroup_cs(cont);
@@ -686,7 +719,7 @@ restart:
cpus_or(*dp, *dp, b->cpus_allowed);
b->pn = -1;
if (dattr)
- update_domain_attr(dattr
+ update_domain_attr_tree(dattr
+ nslot, b);
}
}