Commit b70cc5fd authored by Li Zefan's avatar Li Zefan Committed by Linus Torvalds

cgroups: clean up cgroup_pidlist_find() a bit

Don't call get_pid_ns() before we locate/alloc the ns.
Signed-off-by: default avatarLi Zefan <lizf@cn.fujitsu.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Acked-by: default avatarPaul Menage <menage@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 67523c48
...@@ -2597,7 +2597,8 @@ static struct cgroup_pidlist *cgroup_pidlist_find(struct cgroup *cgrp, ...@@ -2597,7 +2597,8 @@ static struct cgroup_pidlist *cgroup_pidlist_find(struct cgroup *cgrp,
{ {
struct cgroup_pidlist *l; struct cgroup_pidlist *l;
/* don't need task_nsproxy() if we're looking at ourself */ /* don't need task_nsproxy() if we're looking at ourself */
struct pid_namespace *ns = get_pid_ns(current->nsproxy->pid_ns); struct pid_namespace *ns = current->nsproxy->pid_ns;
/* /*
* We can't drop the pidlist_mutex before taking the l->mutex in case * We can't drop the pidlist_mutex before taking the l->mutex in case
* the last ref-holder is trying to remove l from the list at the same * the last ref-holder is trying to remove l from the list at the same
...@@ -2607,8 +2608,6 @@ static struct cgroup_pidlist *cgroup_pidlist_find(struct cgroup *cgrp, ...@@ -2607,8 +2608,6 @@ static struct cgroup_pidlist *cgroup_pidlist_find(struct cgroup *cgrp,
mutex_lock(&cgrp->pidlist_mutex); mutex_lock(&cgrp->pidlist_mutex);
list_for_each_entry(l, &cgrp->pidlists, links) { list_for_each_entry(l, &cgrp->pidlists, links) {
if (l->key.type == type && l->key.ns == ns) { if (l->key.type == type && l->key.ns == ns) {
/* found a matching list - drop the extra refcount */
put_pid_ns(ns);
/* make sure l doesn't vanish out from under us */ /* make sure l doesn't vanish out from under us */
down_write(&l->mutex); down_write(&l->mutex);
mutex_unlock(&cgrp->pidlist_mutex); mutex_unlock(&cgrp->pidlist_mutex);
...@@ -2619,13 +2618,12 @@ static struct cgroup_pidlist *cgroup_pidlist_find(struct cgroup *cgrp, ...@@ -2619,13 +2618,12 @@ static struct cgroup_pidlist *cgroup_pidlist_find(struct cgroup *cgrp,
l = kmalloc(sizeof(struct cgroup_pidlist), GFP_KERNEL); l = kmalloc(sizeof(struct cgroup_pidlist), GFP_KERNEL);
if (!l) { if (!l) {
mutex_unlock(&cgrp->pidlist_mutex); mutex_unlock(&cgrp->pidlist_mutex);
put_pid_ns(ns);
return l; return l;
} }
init_rwsem(&l->mutex); init_rwsem(&l->mutex);
down_write(&l->mutex); down_write(&l->mutex);
l->key.type = type; l->key.type = type;
l->key.ns = ns; l->key.ns = get_pid_ns(ns);
l->use_count = 0; /* don't increment here */ l->use_count = 0; /* don't increment here */
l->list = NULL; l->list = NULL;
l->owner = cgrp; l->owner = cgrp;
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment