mm: restore zone->all_unreclaimable to independence word
commit e815af95 ("change all_unreclaimable zone member to flags") changed
all_unreclaimable member to bit flag. But it had an undesireble side
effect. free_one_page() is one of most hot path in linux kernel and
increasing atomic ops in it can reduce kernel performance a bit.
Thus, this patch revert such commit partially. at least
all_unreclaimable shouldn't share memory word with other zone flags.
[akpm@linux-foundation.org: fix patch interaction]
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Huang Shijie <shijie8@gmail.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 bc0f8db..5cbf64dd 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1699,8 +1699,7 @@
continue;
note_zone_scanning_priority(zone, priority);
- if (zone_is_all_unreclaimable(zone) &&
- priority != DEF_PRIORITY)
+ if (zone->all_unreclaimable && priority != DEF_PRIORITY)
continue; /* Let kswapd poll it */
sc->all_unreclaimable = 0;
} else {
@@ -1927,7 +1926,7 @@
if (!populated_zone(zone))
continue;
- if (zone_is_all_unreclaimable(zone))
+ if (zone->all_unreclaimable)
continue;
if (!zone_watermark_ok(zone, order, high_wmark_pages(zone),
@@ -2017,8 +2016,7 @@
if (!populated_zone(zone))
continue;
- if (zone_is_all_unreclaimable(zone) &&
- priority != DEF_PRIORITY)
+ if (zone->all_unreclaimable && priority != DEF_PRIORITY)
continue;
/*
@@ -2061,8 +2059,7 @@
if (!populated_zone(zone))
continue;
- if (zone_is_all_unreclaimable(zone) &&
- priority != DEF_PRIORITY)
+ if (zone->all_unreclaimable && priority != DEF_PRIORITY)
continue;
temp_priority[i] = priority;
@@ -2089,12 +2086,11 @@
lru_pages);
sc.nr_reclaimed += reclaim_state->reclaimed_slab;
total_scanned += sc.nr_scanned;
- if (zone_is_all_unreclaimable(zone))
+ if (zone->all_unreclaimable)
continue;
- if (nr_slab == 0 && zone->pages_scanned >=
- (zone_reclaimable_pages(zone) * 6))
- zone_set_flag(zone,
- ZONE_ALL_UNRECLAIMABLE);
+ if (nr_slab == 0 &&
+ zone->pages_scanned >= (zone_reclaimable_pages(zone) * 6))
+ zone->all_unreclaimable = 1;
/*
* If we've done a decent amount of scanning and
* the reclaim ratio is low, start doing writepage
@@ -2624,7 +2620,7 @@
zone_page_state(zone, NR_SLAB_RECLAIMABLE) <= zone->min_slab_pages)
return ZONE_RECLAIM_FULL;
- if (zone_is_all_unreclaimable(zone))
+ if (zone->all_unreclaimable)
return ZONE_RECLAIM_FULL;
/*