From: Li Zefan Date: Wed, 10 Mar 2010 23:22:12 +0000 (-0800) Subject: cgroups: clean up cgroup_pidlist_find() a bit X-Git-Tag: MMI-PSA29.97-13-9~24505 X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=b70cc5fdb445a6929a01e9c406593265b136c99d;p=GitHub%2FMotorolaMobilityLLC%2Fkernel-slsi.git cgroups: clean up cgroup_pidlist_find() a bit Don't call get_pid_ns() before we locate/alloc the ns. Signed-off-by: Li Zefan Cc: Serge Hallyn Acked-by: Paul Menage Cc: KAMEZAWA Hiroyuki Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 521591dbab2f..1bf4d6db54ab 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -2597,7 +2597,8 @@ static struct cgroup_pidlist *cgroup_pidlist_find(struct cgroup *cgrp, { struct cgroup_pidlist *l; /* 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 * 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, mutex_lock(&cgrp->pidlist_mutex); list_for_each_entry(l, &cgrp->pidlists, links) { 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 */ down_write(&l->mutex); mutex_unlock(&cgrp->pidlist_mutex); @@ -2619,13 +2618,12 @@ static struct cgroup_pidlist *cgroup_pidlist_find(struct cgroup *cgrp, l = kmalloc(sizeof(struct cgroup_pidlist), GFP_KERNEL); if (!l) { mutex_unlock(&cgrp->pidlist_mutex); - put_pid_ns(ns); return l; } init_rwsem(&l->mutex); down_write(&l->mutex); l->key.type = type; - l->key.ns = ns; + l->key.ns = get_pid_ns(ns); l->use_count = 0; /* don't increment here */ l->list = NULL; l->owner = cgrp;