Subject: + memcg-dont-need-to-free-memcg-via-rcu-or-workqueue.patch added to -mm tree
To: lizefan@xxxxxxxxxx,glommer@xxxxxxxxxx,hannes@xxxxxxxxxxx,hughd@xxxxxxxxxx,kamezawa.hiroyu@xxxxxxxxxxxxxx,mhocko@xxxxxxx,tj@xxxxxxxxxx
From: akpm@xxxxxxxxxxxxxxxxxxxx
Date: Fri, 28 Jun 2013 16:00:34 -0700
The patch titled
Subject: memcg: don't need to free memcg via RCU or workqueue
has been added to the -mm tree. Its filename is
memcg-dont-need-to-free-memcg-via-rcu-or-workqueue.patch
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------------------------------------------------------
From: Li Zefan <lizefan@xxxxxxxxxx>
Subject: memcg: don't need to free memcg via RCU or workqueue
Now memcg has the same life cycle with its corresponding cgroup, and a
cgroup is freed via RCU and then mem_cgroup_css_free() will be called in a
work function, so we can simply call __mem_cgroup_free() in
mem_cgroup_css_free().
This actually reverts 59927fb984d ("memcg: free mem_cgroup by RCU to fix
oops").
Signed-off-by: Li Zefan <lizefan@xxxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxx>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: Glauber Costa <glommer@xxxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/memcontrol.c | 51 ++++------------------------------------------
1 file changed, 5 insertions(+), 46 deletions(-)
diff -puN mm/memcontrol.c~memcg-dont-need-to-free-memcg-via-rcu-or-workqueue mm/memcontrol.c
--- a/mm/memcontrol.c~memcg-dont-need-to-free-memcg-via-rcu-or-workqueue
+++ a/mm/memcontrol.c
@@ -263,28 +263,10 @@ struct mem_cgroup {
/* vmpressure notifications */
struct vmpressure vmpressure;
- union {
- /*
- * the counter to account for mem+swap usage.
- */
- struct res_counter memsw;
-
- /*
- * rcu_freeing is used only when freeing struct mem_cgroup,
- * so put it into a union to avoid wasting more memory.
- * It must be disjoint from the css field. It could be
- * in a union with the res field, but res plays a much
- * larger part in mem_cgroup life than memsw, and might
- * be of interest, even at time of free, when debugging.
- * So share rcu_head with the less interesting memsw.
- */
- struct rcu_head rcu_freeing;
- /*
- * We also need some space for a worker in deferred freeing.
- * By the time we call it, rcu_freeing is no longer in use.
- */
- struct work_struct work_freeing;
- };
+ /*
+ * the counter to account for mem+swap usage.
+ */
+ struct res_counter memsw;
/*
* the counter to account for kernel memory usage.
@@ -6202,29 +6184,6 @@ static void __mem_cgroup_free(struct mem
vfree(memcg);
}
-
-/*
- * Helpers for freeing a kmalloc()ed/vzalloc()ed mem_cgroup by RCU,
- * but in process context. The work_freeing structure is overlaid
- * on the rcu_freeing structure, which itself is overlaid on memsw.
- */
-static void free_work(struct work_struct *work)
-{
- struct mem_cgroup *memcg;
-
- memcg = container_of(work, struct mem_cgroup, work_freeing);
- __mem_cgroup_free(memcg);
-}
-
-static void free_rcu(struct rcu_head *rcu_head)
-{
- struct mem_cgroup *memcg;
-
- memcg = container_of(rcu_head, struct mem_cgroup, rcu_freeing);
- INIT_WORK(&memcg->work_freeing, free_work);
- schedule_work(&memcg->work_freeing);
-}
-
/*
* Returns the parent mem_cgroup in memcgroup hierarchy with hierarchy enabled.
*/
@@ -6375,7 +6334,7 @@ static void mem_cgroup_css_free(struct c
mem_cgroup_sockets_destroy(memcg);
- call_rcu(&memcg->rcu_freeing, free_rcu);
+ __mem_cgroup_free(memcg);
}
#ifdef CONFIG_MMU
_
Patches currently in -mm which might be from lizefan@xxxxxxxxxx are
origin.patch
linux-next.patch
memcg-update-todo-list-in-documentation.patch
revert-memcg-avoid-dangling-reference-count-in-creation-failure.patch
memcg-kmem-fix-reference-count-handling-on-the-error-path.patch
memcg-use-css_get-in-sock_update_memcg.patch
memcg-dont-use-mem_cgroup_get-when-creating-a-kmemcg-cache.patch
memcg-use-css_get-put-when-charging-uncharging-kmem.patch
memcg-use-css_get-put-when-charging-uncharging-kmem-fix.patch
memcg-use-css_get-put-for-swap-memcg.patch
memcg-dont-need-to-get-a-reference-to-the-parent.patch
memcg-kill-memcg-refcnt.patch
memcg-dont-need-to-free-memcg-via-rcu-or-workqueue.patch
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