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 <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Greg Thelen <gthelen@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Ying Han <yinghan@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/page_cgroup.h b/include/linux/page_cgroup.h
index 7a3af74..a88cdba 100644
--- a/include/linux/page_cgroup.h
+++ b/include/linux/page_cgroup.h
@@ -6,8 +6,6 @@
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 @@
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 df1e180..0e13b2a 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1966,10 +1966,6 @@
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 @@
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 @@
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: