vmscan: remove all_unreclaimable scan control
This scan control is abused to communicate a return value from
shrink_zones(). Write this idiomatically and remove the knob.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/vmscan.c b/mm/vmscan.c
index cd4a5ed..c55763e 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -73,8 +73,6 @@
int swappiness;
- int all_unreclaimable;
-
int order;
/*
@@ -1716,14 +1714,14 @@
* If a zone is deemed to be full of pinned pages then just give it a light
* scan then give up on it.
*/
-static void shrink_zones(int priority, struct zonelist *zonelist,
+static int shrink_zones(int priority, struct zonelist *zonelist,
struct scan_control *sc)
{
enum zone_type high_zoneidx = gfp_zone(sc->gfp_mask);
struct zoneref *z;
struct zone *zone;
+ int progress = 0;
- sc->all_unreclaimable = 1;
for_each_zone_zonelist_nodemask(zone, z, zonelist, high_zoneidx,
sc->nodemask) {
if (!populated_zone(zone))
@@ -1739,19 +1737,19 @@
if (zone->all_unreclaimable && priority != DEF_PRIORITY)
continue; /* Let kswapd poll it */
- sc->all_unreclaimable = 0;
} else {
/*
* Ignore cpuset limitation here. We just want to reduce
* # of used pages by us regardless of memory shortage.
*/
- sc->all_unreclaimable = 0;
mem_cgroup_note_reclaim_priority(sc->mem_cgroup,
priority);
}
shrink_zone(priority, zone, sc);
+ progress = 1;
}
+ return progress;
}
/*
@@ -1805,7 +1803,7 @@
sc->nr_scanned = 0;
if (!priority)
disable_swap_token();
- shrink_zones(priority, zonelist, sc);
+ ret = shrink_zones(priority, zonelist, sc);
/*
* Don't shrink slabs when reclaiming memory from
* over limit cgroups
@@ -1842,7 +1840,7 @@
congestion_wait(BLK_RW_ASYNC, HZ/10);
}
/* top priority shrink_zones still had more to do? don't OOM, then */
- if (!sc->all_unreclaimable && scanning_global_lru(sc))
+ if (ret && scanning_global_lru(sc))
ret = sc->nr_reclaimed;
out:
/*