mm: fix up the vmscan stat in vmstat

The "pgsteal" stat is confusing because it counts both direct reclaim as
well as background reclaim.  However, we have "kswapd_steal" which also
counts background reclaim value.

This patch fixes it and also makes it match the existng "pgscan_" stats.

Test:
pgsteal_kswapd_dma32 447623
pgsteal_kswapd_normal 42272677
pgsteal_kswapd_movable 0
pgsteal_direct_dma32 2801
pgsteal_direct_normal 44353270
pgsteal_direct_movable 0

Signed-off-by: Ying Han <yinghan@google.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Mel Gorman <mel@csn.ul.ie>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dan Magenheimer <dan.magenheimer@oracle.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 3 insertions, 2 deletions

diff --git a/include/linux/vm_event_item.h b/include/linux/vm_event_item.h
index 03b90cdc1921..06f8e3858251 100644
--- a/include/linux/vm_event_item.h
+++ b/include/linux/vm_event_item.h
@@ -26,13 +26,14 @@ enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT,
                 PGFREE, PGACTIVATE, PGDEACTIVATE,
                 PGFAULT, PGMAJFAULT,
                 FOR_ALL_ZONES(PGREFILL),
-                FOR_ALL_ZONES(PGSTEAL),
+                FOR_ALL_ZONES(PGSTEAL_KSWAPD),
+                FOR_ALL_ZONES(PGSTEAL_DIRECT),
                 FOR_ALL_ZONES(PGSCAN_KSWAPD),
                 FOR_ALL_ZONES(PGSCAN_DIRECT),
 #ifdef CONFIG_NUMA
                 PGSCAN_ZONE_RECLAIM_FAILED,
 #endif
-                PGINODESTEAL, SLABS_SCANNED, KSWAPD_STEAL, KSWAPD_INODESTEAL,
+                PGINODESTEAL, SLABS_SCANNED, KSWAPD_INODESTEAL,
                 KSWAPD_LOW_WMARK_HIT_QUICKLY, KSWAPD_HIGH_WMARK_HIT_QUICKLY,
                 KSWAPD_SKIP_CONGESTION_WAIT,
                 PAGEOUTRUN, ALLOCSTALL, PGROTATED,