[patch] mm: memcg: move pc lookup point to commit_charge()
From: Johannes Weiner <hidden>
Date: 2012-04-24 19:31:07
Also in:
linux-mm, lkml
Subsystem:
control group - memory resource controller (memcg), memory management, the rest · Maintainers:
Johannes Weiner, Michal Hocko, Roman Gushchin, Shakeel Butt, Andrew Morton, Linus Torvalds
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 <redacted> Acked-by: Hugh Dickins <redacted> Cc: KAMEZAWA Hiroyuki <redacted> Cc: Michal Hocko <redacted> --- mm/memcontrol.c | 17 +++++------------ 1 files changed, 5 insertions(+), 12 deletions(-)
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 884e936..1a28dd8 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c@@ -2461,10 +2461,10 @@ 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;
@@ -2701,7 +2701,6 @@ 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;
@@ -2715,11 +2714,10 @@ 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; }
@@ -2816,16 +2814,13 @@ 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.
@@ -3254,14 +3249,13 @@ 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; }
@@ -3348,8 +3342,7 @@ 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
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1.7.7.6