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>
This commit is contained in:
Johannes Weiner 2010-05-24 14:32:40 -07:00 committed by Linus Torvalds
parent 142762bd8d
commit 0aeb2339e5

View File

@ -73,8 +73,6 @@ struct scan_control {
int swappiness;
int all_unreclaimable;
int order;
/*
@ -1716,14 +1714,14 @@ static void shrink_zone(int priority, struct zone *zone,
* 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 @@ static void shrink_zones(int priority, struct zonelist *zonelist,
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 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
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 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
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:
/*