+ cls_cgroup-remove-unneeded-cgroup_lock.patch added to -mm tree

+ cls_cgroup-remove-unneeded-cgroup_lock.patch added to -mm tree

[akpm]

The patch titled
     cls_cgroup: remove unneeded cgroup_lock
has been added to the -mm tree.  Its filename is
     cls_cgroup-remove-unneeded-cgroup_lock.patch

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------------------------------------------------------
Subject: cls_cgroup: remove unneeded cgroup_lock
From: Li Zefan <lizf@cn.fujitsu.com>

We can remove this lock here, since we are in cgroup write handler and
thus the cgrp is guaranteed to be valid, and no lock is needed when
writing a u32 variable.

Signed-off-by: Li Zefan <lizf@cn.fujitsuc.com>
Acked-by: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 net/sched/cls_cgroup.c |    6 ------
 1 file changed, 6 deletions(-)

diff -puN net/sched/cls_cgroup.c~cls_cgroup-remove-unneeded-cgroup_lock net/sched/cls_cgroup.c
--- a/net/sched/cls_cgroup.c~cls_cgroup-remove-unneeded-cgroup_lock
+++ a/net/sched/cls_cgroup.c
@@ -62,13 +62,7 @@ static u64 read_classid(struct cgroup *c
 
 static int write_classid(struct cgroup *cgrp, struct cftype *cft, u64 value)
 {
-	if (!cgroup_lock_live_group(cgrp))
-		return -ENODEV;
-
 	cgrp_cls_state(cgrp)->classid = (u32) value;
-
-	cgroup_unlock();
-
 	return 0;
 }
 
_

Patches currently in -mm which might be from lizf@cn.fujitsu.com are

vfs-add-missing-unlock-in-sget.patch
linux-next.patch
cls_cgroup-remove-unneeded-cgroup_lock.patch
memdup_user-introduce.patch
memdup_user-introduce-fix.patch
relax-ns_can_attach-checks-to-allow-attaching-to-grandchild-cgroups.patch
cgroup-css-id-support.patch
cgroup-css-id-support-remove-rcu_read_lock-from-css_get_next.patch
cgroup-fix-frequent-ebusy-at-rmdir.patch
cgroups-more-documentation-for-remount-and-release_agent.patch
cgroups-show-correct-file-mode.patch
cgroups-show-correct-file-mode-fix.patch
cgroups-dont-change-release_agent-when-remount-failed.patch
memcg-use-css-id.patch
memcg-hierarchical-stat.patch
memcg-fix-shrinking-memory-to-return-ebusy-by-fixing-retry-algorithm.patch
memcg-fix-oom-killer-under-memcg.patch
memcg-fix-oom-killer-under-memcg-fix2.patch
memcg-fix-oom-killer-under-memcg-fix.patch
memcg-show-memcg-information-during-oom.patch
memcg-show-memcg-information-during-oom-fix2.patch
memcg-show-memcg-information-during-oom-fix.patch
memcg-show-memcg-information-during-oom-fix-fix.patch
memcg-show-memcg-information-during-oom-fix-fix-checkpatch-fixes.patch
memcg-charge-swapcache-to-proper-memcg.patch
cgroups-use-css-id-in-swap-cgroup-for-saving-memory-v5.patch
cpuset-fix-possible-races-in-cpu-memory-hotplug.patch
cgroups-add-data-field-to-struct-cgroup_scanner.patch
cpuset-rewrite-update_tasks_nodemask.patch
cpuset-avoid-changing-cpusets-mems-when-errno-returned.patch
cpuset-remove-struct-cpuset_hotplug_scanner.patch
cpusets-allow-cpusets-to-be-configured-built-on-non-smp-systems.patch