aboutsummaryrefslogtreecommitdiffstats
path: root/kernel/cpuset.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/cpuset.c')
-rw-r--r--kernel/cpuset.c90
1 files changed, 41 insertions, 49 deletions
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index f33c7153b6d7..b017887d632f 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -1784,56 +1784,20 @@ static struct cftype files[] = {
};
/*
- * post_clone() is called during cgroup_create() when the
- * clone_children mount argument was specified. The cgroup
- * can not yet have any tasks.
- *
- * Currently we refuse to set up the cgroup - thereby
- * refusing the task to be entered, and as a result refusing
- * the sys_unshare() or clone() which initiated it - if any
- * sibling cpusets have exclusive cpus or mem.
- *
- * If this becomes a problem for some users who wish to
- * allow that scenario, then cpuset_post_clone() could be
- * changed to grant parent->cpus_allowed-sibling_cpus_exclusive
- * (and likewise for mems) to the new cgroup. Called with cgroup_mutex
- * held.
- */
-static void cpuset_post_clone(struct cgroup *cgroup)
-{
- struct cgroup *parent, *child;
- struct cpuset *cs, *parent_cs;
-
- parent = cgroup->parent;
- list_for_each_entry(child, &parent->children, sibling) {
- cs = cgroup_cs(child);
- if (is_mem_exclusive(cs) || is_cpu_exclusive(cs))
- return;
- }
- cs = cgroup_cs(cgroup);
- parent_cs = cgroup_cs(parent);
-
- mutex_lock(&callback_mutex);
- cs->mems_allowed = parent_cs->mems_allowed;
- cpumask_copy(cs->cpus_allowed, parent_cs->cpus_allowed);
- mutex_unlock(&callback_mutex);
- return;
-}
-
-/*
- * cpuset_create - create a cpuset
+ * cpuset_css_alloc - allocate a cpuset css
* cont: control group that the new cpuset will be part of
*/
-static struct cgroup_subsys_state *cpuset_create(struct cgroup *cont)
+static struct cgroup_subsys_state *cpuset_css_alloc(struct cgroup *cont)
{
- struct cpuset *cs;
- struct cpuset *parent;
+ struct cgroup *parent_cg = cont->parent;
+ struct cgroup *tmp_cg;
+ struct cpuset *parent, *cs;
- if (!cont->parent) {
+ if (!parent_cg)
return &top_cpuset.css;
- }
- parent = cgroup_cs(cont->parent);
+ parent = cgroup_cs(parent_cg);
+
cs = kmalloc(sizeof(*cs), GFP_KERNEL);
if (!cs)
return ERR_PTR(-ENOMEM);
@@ -1855,7 +1819,36 @@ static struct cgroup_subsys_state *cpuset_create(struct cgroup *cont)
cs->parent = parent;
number_of_cpusets++;
- return &cs->css ;
+
+ if (!test_bit(CGRP_CPUSET_CLONE_CHILDREN, &cont->flags))
+ goto skip_clone;
+
+ /*
+ * Clone @parent's configuration if CGRP_CPUSET_CLONE_CHILDREN is
+ * set. This flag handling is implemented in cgroup core for
+ * histrical reasons - the flag may be specified during mount.
+ *
+ * Currently, if any sibling cpusets have exclusive cpus or mem, we
+ * refuse to clone the configuration - thereby refusing the task to
+ * be entered, and as a result refusing the sys_unshare() or
+ * clone() which initiated it. If this becomes a problem for some
+ * users who wish to allow that scenario, then this could be
+ * changed to grant parent->cpus_allowed-sibling_cpus_exclusive
+ * (and likewise for mems) to the new cgroup.
+ */
+ list_for_each_entry(tmp_cg, &parent_cg->children, sibling) {
+ struct cpuset *tmp_cs = cgroup_cs(tmp_cg);
+
+ if (is_mem_exclusive(tmp_cs) || is_cpu_exclusive(tmp_cs))
+ goto skip_clone;
+ }
+
+ mutex_lock(&callback_mutex);
+ cs->mems_allowed = parent->mems_allowed;
+ cpumask_copy(cs->cpus_allowed, parent->cpus_allowed);
+ mutex_unlock(&callback_mutex);
+skip_clone:
+ return &cs->css;
}
/*
@@ -1864,7 +1857,7 @@ static struct cgroup_subsys_state *cpuset_create(struct cgroup *cont)
* will call async_rebuild_sched_domains().
*/
-static void cpuset_destroy(struct cgroup *cont)
+static void cpuset_css_free(struct cgroup *cont)
{
struct cpuset *cs = cgroup_cs(cont);
@@ -1878,11 +1871,10 @@ static void cpuset_destroy(struct cgroup *cont)
struct cgroup_subsys cpuset_subsys = {
.name = "cpuset",
- .create = cpuset_create,
- .destroy = cpuset_destroy,
+ .css_alloc = cpuset_css_alloc,
+ .css_free = cpuset_css_free,
.can_attach = cpuset_can_attach,
.attach = cpuset_attach,
- .post_clone = cpuset_post_clone,
.subsys_id = cpuset_subsys_id,
.base_cftypes = files,
.early_init = 1,

Privacy Policy