From 2ff76f1193f8481f7e6c29304eea4006e8e51569 Mon Sep 17 00:00:00 2001 From: KAMEZAWA Hiroyuki Date: Wed, 21 Mar 2012 16:34:25 -0700 Subject: [PATCH] memcg: remove PCG_FILE_MAPPED With the new lock scheme for updating memcg's page stat, we don't need a flag PCG_FILE_MAPPED which was duplicated information of page_mapped(). [hughd@google.com: cosmetic fix] [hughd@google.com: add comment to MEM_CGROUP_CHARGE_TYPE_MAPPED case in __mem_cgroup_uncharge_common()] Signed-off-by: KAMEZAWA Hiroyuki Acked-by: Greg Thelen Acked-by: Johannes Weiner Cc: Michal Hocko Cc: KOSAKI Motohiro Cc: Ying Han Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/page_cgroup.h | 6 ------ mm/memcontrol.c | 11 ++++++----- 2 files changed, 6 insertions(+), 11 deletions(-) diff --git a/include/linux/page_cgroup.h b/include/linux/page_cgroup.h index 7a3af748f32..a88cdba2780 100644 --- a/include/linux/page_cgroup.h +++ b/include/linux/page_cgroup.h @@ -6,8 +6,6 @@ enum { PCG_LOCK, /* Lock for pc->mem_cgroup and following bits. */ PCG_USED, /* this object is in use. */ PCG_MIGRATION, /* under page migration */ - /* flags for mem_cgroup and file and I/O status */ - PCG_FILE_MAPPED, /* page is accounted as "mapped" */ __NR_PCG_FLAGS, }; @@ -66,10 +64,6 @@ TESTPCGFLAG(Used, USED) CLEARPCGFLAG(Used, USED) SETPCGFLAG(Used, USED) -SETPCGFLAG(FileMapped, FILE_MAPPED) -CLEARPCGFLAG(FileMapped, FILE_MAPPED) -TESTPCGFLAG(FileMapped, FILE_MAPPED) - SETPCGFLAG(Migration, MIGRATION) CLEARPCGFLAG(Migration, MIGRATION) TESTPCGFLAG(Migration, MIGRATION) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index df1e180f6c3..0e13b2aeea6 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1966,10 +1966,6 @@ void mem_cgroup_update_page_stat(struct page *page, switch (idx) { case MEMCG_NR_FILE_MAPPED: - if (val > 0) - SetPageCgroupFileMapped(pc); - else if (!page_mapped(page)) - ClearPageCgroupFileMapped(pc); idx = MEM_CGROUP_STAT_FILE_MAPPED; break; default: @@ -2617,7 +2613,7 @@ static int mem_cgroup_move_account(struct page *page, move_lock_mem_cgroup(from, &flags); - if (PageCgroupFileMapped(pc)) { + if (!anon && page_mapped(page)) { /* Update mapped_file data for mem_cgroup */ preempt_disable(); __this_cpu_dec(from->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]); @@ -2982,6 +2978,11 @@ __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype) switch (ctype) { case MEM_CGROUP_CHARGE_TYPE_MAPPED: + /* + * Generally PageAnon tells if it's the anon statistics to be + * updated; but sometimes e.g. mem_cgroup_uncharge_page() is + * used before page reached the stage of being marked PageAnon. + */ anon = true; /* fallthrough */ case MEM_CGROUP_CHARGE_TYPE_DROP: