mm: memcontrol: track move_lock state internally

The complexity of memcg page stat synchronization is currently leaking
into the callsites, forcing them to keep track of the move_lock state and
the IRQ flags.  Simplify the API by tracking it in the memcg.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Reviewed-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 8 deletions

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 6f4335238e33..fb71e9deca85 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -2308,12 +2308,10 @@ EXPORT_SYMBOL(clear_page_dirty_for_io);
 int test_clear_page_writeback(struct page *page)
 {
         struct address_space *mapping = page_mapping(page);
-        unsigned long memcg_flags;
         struct mem_cgroup *memcg;
-        bool locked;
         int ret;
 
-        memcg = mem_cgroup_begin_page_stat(page, &locked, &memcg_flags);
+        memcg = mem_cgroup_begin_page_stat(page);
         if (mapping) {
                 struct backing_dev_info *bdi = mapping->backing_dev_info;
                 unsigned long flags;
@@ -2338,19 +2336,17 @@ int test_clear_page_writeback(struct page *page)
                 dec_zone_page_state(page, NR_WRITEBACK);
                 inc_zone_page_state(page, NR_WRITTEN);
         }
-        mem_cgroup_end_page_stat(memcg, &locked, &memcg_flags);
+        mem_cgroup_end_page_stat(memcg);
         return ret;
 }
 
 int __test_set_page_writeback(struct page *page, bool keep_write)
 {
         struct address_space *mapping = page_mapping(page);
-        unsigned long memcg_flags;
         struct mem_cgroup *memcg;
-        bool locked;
         int ret;
 
-        memcg = mem_cgroup_begin_page_stat(page, &locked, &memcg_flags);
+        memcg = mem_cgroup_begin_page_stat(page);
         if (mapping) {
                 struct backing_dev_info *bdi = mapping->backing_dev_info;
                 unsigned long flags;
@@ -2380,7 +2376,7 @@ int __test_set_page_writeback(struct page *page, bool keep_write)
                 mem_cgroup_inc_page_stat(memcg, MEM_CGROUP_STAT_WRITEBACK);
                 inc_zone_page_state(page, NR_WRITEBACK);
         }
-        mem_cgroup_end_page_stat(memcg, &locked, &memcg_flags);
+        mem_cgroup_end_page_stat(memcg);
         return ret;
 
 }