From d833049bd20570cbbadeb5228c579f9f3aaa4e03 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Thu, 12 Apr 2012 12:49:11 -0700 Subject: memcg: fix broken boolen expression action != CPU_DEAD || action != CPU_DEAD_FROZEN is always true. Signed-off-by: Kirill A. Shutemov Acked-by: KAMEZAWA Hiroyuki Acked-by: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memcontrol.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'mm/memcontrol.c') diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 7d698df4a06..ea1e879b2db 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2165,7 +2165,7 @@ static int __cpuinit memcg_cpu_hotplug_callback(struct notifier_block *nb, if (action == CPU_ONLINE) return NOTIFY_OK; - if ((action != CPU_DEAD) || action != CPU_DEAD_FROZEN) + if (action != CPU_DEAD && action != CPU_DEAD_FROZEN) return NOTIFY_OK; for_each_mem_cgroup(iter) -- cgit v1.2.3-70-g09d2 From 569530fb1b40ab2d2ca147ee79898ac807ebdf90 Mon Sep 17 00:00:00 2001 From: Glauber Costa Date: Thu, 12 Apr 2012 12:49:13 -0700 Subject: memcg: do not open code accesses to res_counter members We should use the accessor res_counter_read_u64 for that. Although a purely cosmetic change is sometimes better delayed, to avoid conflicting with other people's work, we are starting to have people touching this code as well, and reproducing the open code behavior because that's the standard =) Time to fix it, then. Signed-off-by: Glauber Costa Cc: Johannes Weiner Acked-by: Michal Hocko Cc: KAMEZAWA Hiroyuki Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memcontrol.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'mm/memcontrol.c') diff --git a/mm/memcontrol.c b/mm/memcontrol.c index ea1e879b2db..a7165a60d0a 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3763,7 +3763,7 @@ move_account: goto try_to_free; cond_resched(); /* "ret" should also be checked to ensure all lists are empty. */ - } while (memcg->res.usage > 0 || ret); + } while (res_counter_read_u64(&memcg->res, RES_USAGE) > 0 || ret); out: css_put(&memcg->css); return ret; @@ -3778,7 +3778,7 @@ try_to_free: lru_add_drain_all(); /* try to free all pages in this cgroup */ shrink = 1; - while (nr_retries && memcg->res.usage > 0) { + while (nr_retries && res_counter_read_u64(&memcg->res, RES_USAGE) > 0) { int progress; if (signal_pending(current)) { -- cgit v1.2.3-70-g09d2 From 9b7f43afd417a6feb80841d30ced4051c362eb5d Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Wed, 18 Apr 2012 23:34:46 -0700 Subject: memcg: fix Bad page state after replace_page_cache My 9ce70c0240d0 "memcg: fix deadlock by inverting lrucare nesting" put a nasty little bug into v3.3's version of mem_cgroup_replace_page_cache(), sometimes used for FUSE. Replacing __mem_cgroup_commit_charge_lrucare() by __mem_cgroup_commit_charge(), I used the "pc" pointer set up earlier: but it's for oldpage, and needs now to be for newpage. Once oldpage was freed, its PageCgroupUsed bit (cleared above but set again here) caused "Bad page state" messages - and perhaps worse, being missed from newpage. (I didn't find this by using FUSE, but in reusing the function for tmpfs.) Signed-off-by: Hugh Dickins Cc: stable@vger.kernel.org [v3.3 only] Signed-off-by: Linus Torvalds --- mm/memcontrol.c | 1 + 1 file changed, 1 insertion(+) (limited to 'mm/memcontrol.c') diff --git a/mm/memcontrol.c b/mm/memcontrol.c index a7165a60d0a..b868def9bcc 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3392,6 +3392,7 @@ void mem_cgroup_replace_page_cache(struct page *oldpage, * the newpage may be on LRU(or pagevec for LRU) already. We lock * LRU while we overwrite pc->mem_cgroup. */ + pc = lookup_page_cgroup(newpage); __mem_cgroup_commit_charge(memcg, newpage, 1, pc, type, true); } -- cgit v1.2.3-70-g09d2 From ce587e65e8c669eec61df7fb1c515720302e3cc0 Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Tue, 24 Apr 2012 20:22:33 +0200 Subject: mm: memcg: move pc lookup point to commit_charge() None of the callsites actually need the page_cgroup descriptor themselves, so just pass the page and do the look up in there. We already had two bugs (6568d4a 'mm: memcg: update the correct soft limit tree during migration' and 'memcg: fix Bad page state after replace_page_cache') where the passed page and pc were not referring to the same page frame. Signed-off-by: Johannes Weiner Acked-by: Hugh Dickins Signed-off-by: Linus Torvalds --- mm/memcontrol.c | 17 +++++------------ 1 file changed, 5 insertions(+), 12 deletions(-) (limited to 'mm/memcontrol.c') diff --git a/mm/memcontrol.c b/mm/memcontrol.c index b868def9bcc..31ab9c3f017 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2476,10 +2476,10 @@ struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page) static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg, struct page *page, unsigned int nr_pages, - struct page_cgroup *pc, enum charge_type ctype, bool lrucare) { + struct page_cgroup *pc = lookup_page_cgroup(page); struct zone *uninitialized_var(zone); bool was_on_lru = false; bool anon; @@ -2716,7 +2716,6 @@ static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, { struct mem_cgroup *memcg = NULL; unsigned int nr_pages = 1; - struct page_cgroup *pc; bool oom = true; int ret; @@ -2730,11 +2729,10 @@ static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, oom = false; } - pc = lookup_page_cgroup(page); ret = __mem_cgroup_try_charge(mm, gfp_mask, nr_pages, &memcg, oom); if (ret == -ENOMEM) return ret; - __mem_cgroup_commit_charge(memcg, page, nr_pages, pc, ctype, false); + __mem_cgroup_commit_charge(memcg, page, nr_pages, ctype, false); return 0; } @@ -2831,16 +2829,13 @@ static void __mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *memcg, enum charge_type ctype) { - struct page_cgroup *pc; - if (mem_cgroup_disabled()) return; if (!memcg) return; cgroup_exclude_rmdir(&memcg->css); - pc = lookup_page_cgroup(page); - __mem_cgroup_commit_charge(memcg, page, 1, pc, ctype, true); + __mem_cgroup_commit_charge(memcg, page, 1, ctype, true); /* * Now swap is on-memory. This means this page may be * counted both as mem and swap....double count. @@ -3298,14 +3293,13 @@ int mem_cgroup_prepare_migration(struct page *page, * page. In the case new page is migrated but not remapped, new page's * mapcount will be finally 0 and we call uncharge in end_migration(). */ - pc = lookup_page_cgroup(newpage); if (PageAnon(page)) ctype = MEM_CGROUP_CHARGE_TYPE_MAPPED; else if (page_is_file_cache(page)) ctype = MEM_CGROUP_CHARGE_TYPE_CACHE; else ctype = MEM_CGROUP_CHARGE_TYPE_SHMEM; - __mem_cgroup_commit_charge(memcg, newpage, 1, pc, ctype, false); + __mem_cgroup_commit_charge(memcg, newpage, 1, ctype, false); return ret; } @@ -3392,8 +3386,7 @@ void mem_cgroup_replace_page_cache(struct page *oldpage, * the newpage may be on LRU(or pagevec for LRU) already. We lock * LRU while we overwrite pc->mem_cgroup. */ - pc = lookup_page_cgroup(newpage); - __mem_cgroup_commit_charge(memcg, newpage, 1, pc, type, true); + __mem_cgroup_commit_charge(memcg, newpage, 1, type, true); } #ifdef CONFIG_DEBUG_VM -- cgit v1.2.3-70-g09d2