* [RFC][BUGFIX] memcg: fix memsw uncharged twice in do_swap_page
@ 2011-12-13 7:55 Bob Liu
2011-12-13 8:02 ` KAMEZAWA Hiroyuki
2011-12-13 8:10 ` Daisuke Nishimura
0 siblings, 2 replies; 4+ messages in thread
From: Bob Liu @ 2011-12-13 7:55 UTC (permalink / raw)
To: linux-mm; +Cc: kamezawa.hiroyu, mhocko, hannes, bsingharora, Bob Liu
As the document memcg_test.txt said:
In do_swap_page(), following events occur when pte is unchanged.
(1) the page (SwapCache) is looked up.
(2) lock_page()
(3) try_charge_swapin()
(4) reuse_swap_page() (may call delete_swap_cache())
(5) commit_charge_swapin()
(6) swap_free().
And below situation:
(C) The page has been charged before (2) and reuse_swap_page() doesn't
call delete_from_swap_cache().
In this case, __mem_cgroup_commit_charge_swapin() may uncharge memsw twice.
See below two uncharge place:
__mem_cgroup_commit_charge_swapin {
=> __mem_cgroup_commit_charge_lrucare
=> __mem_cgroup_commit_charge() <== PageCgroupUsed
=> __mem_cgroup_cancel_charge()
<== 1.uncharge memsw here
if (do_swap_account && PageSwapCache(page)) {
if (swap_memcg) {
if (!mem_cgroup_is_root(swap_memcg))
res_counter_uncharge(&swap_memcg->memsw,
PAGE_SIZE);
<== 2.uncharged memsw again here
mem_cgroup_swap_statistics(swap_memcg, false);
mem_cgroup_put(swap_memcg);
}
}
}
This patch added a return val for __mem_cgroup_commit_charge(), if canceled then
don't uncharge memsw again.
But i didn't find a definite testcase can confirm this situaction current.
Maybe i missed something. Welcome point.
Signed-off-by: Bob Liu <lliubbo@gmail.com>
---
mm/memcontrol.c | 56 +++++++++++++++++++++++++++++++-----------------------
1 files changed, 32 insertions(+), 24 deletions(-)
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index bc396e7..6ead0cd 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2416,7 +2416,10 @@ struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page)
return memcg;
}
-static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg,
+/*
+ * return -1 if cancel charge else return 0
+ */
+static int __mem_cgroup_commit_charge(struct mem_cgroup *memcg,
struct page *page,
unsigned int nr_pages,
struct page_cgroup *pc,
@@ -2426,7 +2429,7 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg,
if (unlikely(PageCgroupUsed(pc))) {
unlock_page_cgroup(pc);
__mem_cgroup_cancel_charge(memcg, nr_pages);
- return;
+ return -1;
}
/*
* we don't need page_cgroup_lock about tail pages, becase they are not
@@ -2463,6 +2466,7 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg,
* if they exceeds softlimit.
*/
memcg_check_events(memcg, page);
+ return 0;
}
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
@@ -2690,20 +2694,21 @@ static void
__mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr,
enum charge_type ctype);
-static void
+static int
__mem_cgroup_commit_charge_lrucare(struct page *page, struct mem_cgroup *memcg,
enum charge_type ctype)
{
struct page_cgroup *pc = lookup_page_cgroup(page);
+ int ret;
/*
* In some case, SwapCache, FUSE(splice_buf->radixtree), the page
* is already on LRU. It means the page may on some other page_cgroup's
* LRU. Take care of it.
*/
mem_cgroup_lru_del_before_commit(page);
- __mem_cgroup_commit_charge(memcg, page, 1, pc, ctype);
+ ret = __mem_cgroup_commit_charge(memcg, page, 1, pc, ctype);
mem_cgroup_lru_add_after_commit(page);
- return;
+ return ret;
}
int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm,
@@ -2792,13 +2797,14 @@ static void
__mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *memcg,
enum charge_type ctype)
{
+ int ret;
if (mem_cgroup_disabled())
return;
if (!memcg)
return;
cgroup_exclude_rmdir(&memcg->css);
- __mem_cgroup_commit_charge_lrucare(page, memcg, ctype);
+ ret = __mem_cgroup_commit_charge_lrucare(page, memcg, ctype);
/*
* Now swap is on-memory. This means this page may be
* counted both as mem and swap....double count.
@@ -2807,25 +2813,27 @@ __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *memcg,
* may call delete_from_swap_cache() before reach here.
*/
if (do_swap_account && PageSwapCache(page)) {
- swp_entry_t ent = {.val = page_private(page)};
- struct mem_cgroup *swap_memcg;
- unsigned short id;
+ if(!ret) {
+ swp_entry_t ent = {.val = page_private(page)};
+ struct mem_cgroup *swap_memcg;
+ unsigned short id;
- id = swap_cgroup_record(ent, 0);
- rcu_read_lock();
- swap_memcg = mem_cgroup_lookup(id);
- if (swap_memcg) {
- /*
- * This recorded memcg can be obsolete one. So, avoid
- * calling css_tryget
- */
- if (!mem_cgroup_is_root(swap_memcg))
- res_counter_uncharge(&swap_memcg->memsw,
- PAGE_SIZE);
- mem_cgroup_swap_statistics(swap_memcg, false);
- mem_cgroup_put(swap_memcg);
+ id = swap_cgroup_record(ent, 0);
+ rcu_read_lock();
+ swap_memcg = mem_cgroup_lookup(id);
+ if (swap_memcg) {
+ /*
+ * This recorded memcg can be obsolete one. So, avoid
+ * calling css_tryget
+ */
+ if (!mem_cgroup_is_root(swap_memcg))
+ res_counter_uncharge(&swap_memcg->memsw,
+ PAGE_SIZE);
+ mem_cgroup_swap_statistics(swap_memcg, false);
+ mem_cgroup_put(swap_memcg);
+ }
+ rcu_read_unlock();
}
- rcu_read_unlock();
}
/*
* At swapin, we may charge account against cgroup which has no tasks.
--
1.7.0.4
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* Re: [RFC][BUGFIX] memcg: fix memsw uncharged twice in do_swap_page
2011-12-13 7:55 [RFC][BUGFIX] memcg: fix memsw uncharged twice in do_swap_page Bob Liu
@ 2011-12-13 8:02 ` KAMEZAWA Hiroyuki
2011-12-13 8:10 ` Daisuke Nishimura
1 sibling, 0 replies; 4+ messages in thread
From: KAMEZAWA Hiroyuki @ 2011-12-13 8:02 UTC (permalink / raw)
To: Bob Liu; +Cc: linux-mm, mhocko, hannes, bsingharora
On Tue, 13 Dec 2011 15:55:25 +0800
Bob Liu <lliubbo@gmail.com> wrote:
> As the document memcg_test.txt said:
> In do_swap_page(), following events occur when pte is unchanged.
> (1) the page (SwapCache) is looked up.
> (2) lock_page()
> (3) try_charge_swapin()
> (4) reuse_swap_page() (may call delete_swap_cache())
> (5) commit_charge_swapin()
> (6) swap_free().
>
> And below situation:
> (C) The page has been charged before (2) and reuse_swap_page() doesn't
> call delete_from_swap_cache().
>
> In this case, __mem_cgroup_commit_charge_swapin() may uncharge memsw twice.
> See below two uncharge place:
>
> __mem_cgroup_commit_charge_swapin {
> => __mem_cgroup_commit_charge_lrucare
> => __mem_cgroup_commit_charge() <== PageCgroupUsed
> => __mem_cgroup_cancel_charge()
> <== 1.uncharge memsw here
>
> if (do_swap_account && PageSwapCache(page)) {
> if (swap_memcg) {
> if (!mem_cgroup_is_root(swap_memcg))
> res_counter_uncharge(&swap_memcg->memsw,
> PAGE_SIZE);
> <== 2.uncharged memsw again here
>
> mem_cgroup_swap_statistics(swap_memcg, false);
> mem_cgroup_put(swap_memcg);
> }
> }
> }
How this happens ?
1. all swap-cache handling is serialized by lock_page().
2. If the page_cgroup is marked as PCG_USED, record in swap_cgroup must be cleared.
and swap_memcg never be found.
There is no real bug. If you want to add VM_BUG_ON() as
commit_charge() decreases memsw count but swap_cgroup is found.
ok, please write a patch.
Nack to this patch.
Thanks,
-Kame
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^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [RFC][BUGFIX] memcg: fix memsw uncharged twice in do_swap_page
2011-12-13 7:55 [RFC][BUGFIX] memcg: fix memsw uncharged twice in do_swap_page Bob Liu
2011-12-13 8:02 ` KAMEZAWA Hiroyuki
@ 2011-12-13 8:10 ` Daisuke Nishimura
2011-12-14 2:08 ` Bob Liu
1 sibling, 1 reply; 4+ messages in thread
From: Daisuke Nishimura @ 2011-12-13 8:10 UTC (permalink / raw)
To: Bob Liu
Cc: linux-mm, kamezawa.hiroyu, mhocko, hannes, bsingharora,
Daisuke Nishimura
Hi,
On Tue, 13 Dec 2011 15:55:25 +0800
Bob Liu <lliubbo@gmail.com> wrote:
> As the document memcg_test.txt said:
> In do_swap_page(), following events occur when pte is unchanged.
> (1) the page (SwapCache) is looked up.
> (2) lock_page()
> (3) try_charge_swapin()
> (4) reuse_swap_page() (may call delete_swap_cache())
> (5) commit_charge_swapin()
> (6) swap_free().
>
> And below situation:
> (C) The page has been charged before (2) and reuse_swap_page() doesn't
> call delete_from_swap_cache().
>
> In this case, __mem_cgroup_commit_charge_swapin() may uncharge memsw twice.
> See below two uncharge place:
>
> __mem_cgroup_commit_charge_swapin {
> => __mem_cgroup_commit_charge_lrucare
> => __mem_cgroup_commit_charge() <== PageCgroupUsed
> => __mem_cgroup_cancel_charge()
> <== 1.uncharge memsw here
>
> if (do_swap_account && PageSwapCache(page)) {
> if (swap_memcg) {
IIRC, if the page(swapcache) has been already charged as memory, swap_cgroup_record(ent, 0)
returns 0, so swap_memcg is NULL.
Thanks,
Daisuke Nishimura.
> if (!mem_cgroup_is_root(swap_memcg))
> res_counter_uncharge(&swap_memcg->memsw,
> PAGE_SIZE);
> <== 2.uncharged memsw again here
>
> mem_cgroup_swap_statistics(swap_memcg, false);
> mem_cgroup_put(swap_memcg);
> }
> }
> }
>
> This patch added a return val for __mem_cgroup_commit_charge(), if canceled then
> don't uncharge memsw again.
>
> But i didn't find a definite testcase can confirm this situaction current.
> Maybe i missed something. Welcome point.
>
> Signed-off-by: Bob Liu <lliubbo@gmail.com>
> ---
> mm/memcontrol.c | 56 +++++++++++++++++++++++++++++++-----------------------
> 1 files changed, 32 insertions(+), 24 deletions(-)
>
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index bc396e7..6ead0cd 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -2416,7 +2416,10 @@ struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page)
> return memcg;
> }
>
> -static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg,
> +/*
> + * return -1 if cancel charge else return 0
> + */
> +static int __mem_cgroup_commit_charge(struct mem_cgroup *memcg,
> struct page *page,
> unsigned int nr_pages,
> struct page_cgroup *pc,
> @@ -2426,7 +2429,7 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg,
> if (unlikely(PageCgroupUsed(pc))) {
> unlock_page_cgroup(pc);
> __mem_cgroup_cancel_charge(memcg, nr_pages);
> - return;
> + return -1;
> }
> /*
> * we don't need page_cgroup_lock about tail pages, becase they are not
> @@ -2463,6 +2466,7 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg,
> * if they exceeds softlimit.
> */
> memcg_check_events(memcg, page);
> + return 0;
> }
>
> #ifdef CONFIG_TRANSPARENT_HUGEPAGE
> @@ -2690,20 +2694,21 @@ static void
> __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr,
> enum charge_type ctype);
>
> -static void
> +static int
> __mem_cgroup_commit_charge_lrucare(struct page *page, struct mem_cgroup *memcg,
> enum charge_type ctype)
> {
> struct page_cgroup *pc = lookup_page_cgroup(page);
> + int ret;
> /*
> * In some case, SwapCache, FUSE(splice_buf->radixtree), the page
> * is already on LRU. It means the page may on some other page_cgroup's
> * LRU. Take care of it.
> */
> mem_cgroup_lru_del_before_commit(page);
> - __mem_cgroup_commit_charge(memcg, page, 1, pc, ctype);
> + ret = __mem_cgroup_commit_charge(memcg, page, 1, pc, ctype);
> mem_cgroup_lru_add_after_commit(page);
> - return;
> + return ret;
> }
>
> int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm,
> @@ -2792,13 +2797,14 @@ static void
> __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *memcg,
> enum charge_type ctype)
> {
> + int ret;
> if (mem_cgroup_disabled())
> return;
> if (!memcg)
> return;
> cgroup_exclude_rmdir(&memcg->css);
>
> - __mem_cgroup_commit_charge_lrucare(page, memcg, ctype);
> + ret = __mem_cgroup_commit_charge_lrucare(page, memcg, ctype);
> /*
> * Now swap is on-memory. This means this page may be
> * counted both as mem and swap....double count.
> @@ -2807,25 +2813,27 @@ __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *memcg,
> * may call delete_from_swap_cache() before reach here.
> */
> if (do_swap_account && PageSwapCache(page)) {
> - swp_entry_t ent = {.val = page_private(page)};
> - struct mem_cgroup *swap_memcg;
> - unsigned short id;
> + if(!ret) {
> + swp_entry_t ent = {.val = page_private(page)};
> + struct mem_cgroup *swap_memcg;
> + unsigned short id;
>
> - id = swap_cgroup_record(ent, 0);
> - rcu_read_lock();
> - swap_memcg = mem_cgroup_lookup(id);
> - if (swap_memcg) {
> - /*
> - * This recorded memcg can be obsolete one. So, avoid
> - * calling css_tryget
> - */
> - if (!mem_cgroup_is_root(swap_memcg))
> - res_counter_uncharge(&swap_memcg->memsw,
> - PAGE_SIZE);
> - mem_cgroup_swap_statistics(swap_memcg, false);
> - mem_cgroup_put(swap_memcg);
> + id = swap_cgroup_record(ent, 0);
> + rcu_read_lock();
> + swap_memcg = mem_cgroup_lookup(id);
> + if (swap_memcg) {
> + /*
> + * This recorded memcg can be obsolete one. So, avoid
> + * calling css_tryget
> + */
> + if (!mem_cgroup_is_root(swap_memcg))
> + res_counter_uncharge(&swap_memcg->memsw,
> + PAGE_SIZE);
> + mem_cgroup_swap_statistics(swap_memcg, false);
> + mem_cgroup_put(swap_memcg);
> + }
> + rcu_read_unlock();
> }
> - rcu_read_unlock();
> }
> /*
> * At swapin, we may charge account against cgroup which has no tasks.
> --
> 1.7.0.4
>
>
> --
> To unsubscribe, send a message with 'unsubscribe linux-mm' in
> the body to majordomo@kvack.org. For more info on Linux MM,
> see: http://www.linux-mm.org/ .
> Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
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^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [RFC][BUGFIX] memcg: fix memsw uncharged twice in do_swap_page
2011-12-13 8:10 ` Daisuke Nishimura
@ 2011-12-14 2:08 ` Bob Liu
0 siblings, 0 replies; 4+ messages in thread
From: Bob Liu @ 2011-12-14 2:08 UTC (permalink / raw)
To: Daisuke Nishimura; +Cc: linux-mm, kamezawa.hiroyu, mhocko, hannes, bsingharora
On Tue, Dec 13, 2011 at 4:10 PM, Daisuke Nishimura
<nishimura@mxp.nes.nec.co.jp> wrote:
> Hi,
>
> On Tue, 13 Dec 2011 15:55:25 +0800
> Bob Liu <lliubbo@gmail.com> wrote:
>
>> As the document memcg_test.txt said:
>> In do_swap_page(), following events occur when pte is unchanged.
>> (1) the page (SwapCache) is looked up.
>> (2) lock_page()
>> (3) try_charge_swapin()
>> (4) reuse_swap_page() (may call delete_swap_cache())
>> (5) commit_charge_swapin()
>> (6) swap_free().
>>
>> And below situation:
>> (C) The page has been charged before (2) and reuse_swap_page() doesn't
>> call delete_from_swap_cache().
>>
>> In this case, __mem_cgroup_commit_charge_swapin() may uncharge memsw twice.
>> See below two uncharge place:
>>
>> __mem_cgroup_commit_charge_swapin {
>> => __mem_cgroup_commit_charge_lrucare
>> => __mem_cgroup_commit_charge() <== PageCgroupUsed
>> => __mem_cgroup_cancel_charge()
>> <== 1.uncharge memsw here
>>
>> if (do_swap_account && PageSwapCache(page)) {
>> if (swap_memcg) {
> IIRC, if the page(swapcache) has been already charged as memory, swap_cgroup_record(ent, 0)
> returns 0, so swap_memcg is NULL.
>
Got it, sorry for my noise.
Thank you for all.
> Thanks,
> Daisuke Nishimura.
>
>> if (!mem_cgroup_is_root(swap_memcg))
>> res_counter_uncharge(&swap_memcg->memsw,
>> PAGE_SIZE);
>> <== 2.uncharged memsw again here
>>
>> mem_cgroup_swap_statistics(swap_memcg, false);
>> mem_cgroup_put(swap_memcg);
>> }
>> }
>> }
>>
>> This patch added a return val for __mem_cgroup_commit_charge(), if canceled then
>> don't uncharge memsw again.
>>
>> But i didn't find a definite testcase can confirm this situaction current.
>> Maybe i missed something. Welcome point.
>>
>> Signed-off-by: Bob Liu <lliubbo@gmail.com>
>> ---
>> mm/memcontrol.c | 56 +++++++++++++++++++++++++++++++-----------------------
>> 1 files changed, 32 insertions(+), 24 deletions(-)
>>
>> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
>> index bc396e7..6ead0cd 100644
>> --- a/mm/memcontrol.c
>> +++ b/mm/memcontrol.c
>> @@ -2416,7 +2416,10 @@ struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page)
>> return memcg;
>> }
>>
>> -static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg,
>> +/*
>> + * return -1 if cancel charge else return 0
>> + */
>> +static int __mem_cgroup_commit_charge(struct mem_cgroup *memcg,
>> struct page *page,
>> unsigned int nr_pages,
>> struct page_cgroup *pc,
>> @@ -2426,7 +2429,7 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg,
>> if (unlikely(PageCgroupUsed(pc))) {
>> unlock_page_cgroup(pc);
>> __mem_cgroup_cancel_charge(memcg, nr_pages);
>> - return;
>> + return -1;
>> }
>> /*
>> * we don't need page_cgroup_lock about tail pages, becase they are not
>> @@ -2463,6 +2466,7 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg,
>> * if they exceeds softlimit.
>> */
>> memcg_check_events(memcg, page);
>> + return 0;
>> }
>>
>> #ifdef CONFIG_TRANSPARENT_HUGEPAGE
>> @@ -2690,20 +2694,21 @@ static void
>> __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr,
>> enum charge_type ctype);
>>
>> -static void
>> +static int
>> __mem_cgroup_commit_charge_lrucare(struct page *page, struct mem_cgroup *memcg,
>> enum charge_type ctype)
>> {
>> struct page_cgroup *pc = lookup_page_cgroup(page);
>> + int ret;
>> /*
>> * In some case, SwapCache, FUSE(splice_buf->radixtree), the page
>> * is already on LRU. It means the page may on some other page_cgroup's
>> * LRU. Take care of it.
>> */
>> mem_cgroup_lru_del_before_commit(page);
>> - __mem_cgroup_commit_charge(memcg, page, 1, pc, ctype);
>> + ret = __mem_cgroup_commit_charge(memcg, page, 1, pc, ctype);
>> mem_cgroup_lru_add_after_commit(page);
>> - return;
>> + return ret;
>> }
>>
>> int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm,
>> @@ -2792,13 +2797,14 @@ static void
>> __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *memcg,
>> enum charge_type ctype)
>> {
>> + int ret;
>> if (mem_cgroup_disabled())
>> return;
>> if (!memcg)
>> return;
>> cgroup_exclude_rmdir(&memcg->css);
>>
>> - __mem_cgroup_commit_charge_lrucare(page, memcg, ctype);
>> + ret = __mem_cgroup_commit_charge_lrucare(page, memcg, ctype);
>> /*
>> * Now swap is on-memory. This means this page may be
>> * counted both as mem and swap....double count.
>> @@ -2807,25 +2813,27 @@ __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *memcg,
>> * may call delete_from_swap_cache() before reach here.
>> */
>> if (do_swap_account && PageSwapCache(page)) {
>> - swp_entry_t ent = {.val = page_private(page)};
>> - struct mem_cgroup *swap_memcg;
>> - unsigned short id;
>> + if(!ret) {
>> + swp_entry_t ent = {.val = page_private(page)};
>> + struct mem_cgroup *swap_memcg;
>> + unsigned short id;
>>
>> - id = swap_cgroup_record(ent, 0);
>> - rcu_read_lock();
>> - swap_memcg = mem_cgroup_lookup(id);
>> - if (swap_memcg) {
>> - /*
>> - * This recorded memcg can be obsolete one. So, avoid
>> - * calling css_tryget
>> - */
>> - if (!mem_cgroup_is_root(swap_memcg))
>> - res_counter_uncharge(&swap_memcg->memsw,
>> - PAGE_SIZE);
>> - mem_cgroup_swap_statistics(swap_memcg, false);
>> - mem_cgroup_put(swap_memcg);
>> + id = swap_cgroup_record(ent, 0);
>> + rcu_read_lock();
>> + swap_memcg = mem_cgroup_lookup(id);
>> + if (swap_memcg) {
>> + /*
>> + * This recorded memcg can be obsolete one. So, avoid
>> + * calling css_tryget
>> + */
>> + if (!mem_cgroup_is_root(swap_memcg))
>> + res_counter_uncharge(&swap_memcg->memsw,
>> + PAGE_SIZE);
>> + mem_cgroup_swap_statistics(swap_memcg, false);
>> + mem_cgroup_put(swap_memcg);
>> + }
>> + rcu_read_unlock();
>> }
>> - rcu_read_unlock();
>> }
>> /*
>> * At swapin, we may charge account against cgroup which has no tasks.
>> --
>> 1.7.0.4
>>
>>
--
Regards,
--Bob
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2011-12-14 2:08 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2011-12-13 7:55 [RFC][BUGFIX] memcg: fix memsw uncharged twice in do_swap_page Bob Liu
2011-12-13 8:02 ` KAMEZAWA Hiroyuki
2011-12-13 8:10 ` Daisuke Nishimura
2011-12-14 2:08 ` Bob Liu
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