vmscan: update isolated page counters outside of main path in shrink_inactive_list()
When shrink_inactive_list() isolates pages, it updates a number of
counters using temporary variables to gather them. These consume stack
and it's in the main path that calls ->writepage(). This patch moves the
accounting updates outside of the main path to reduce stack usage.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Michael Rubin <mrubin@google.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 512f463..1c3d960 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1076,7 +1076,8 @@
ClearPageActive(page);
nr_active++;
}
- count[lru]++;
+ if (count)
+ count[lru]++;
}
return nr_active;
@@ -1156,12 +1157,13 @@
* TODO: Try merging with migrations version of putback_lru_pages
*/
static noinline_for_stack void
-putback_lru_pages(struct zone *zone, struct zone_reclaim_stat *reclaim_stat,
+putback_lru_pages(struct zone *zone, struct scan_control *sc,
unsigned long nr_anon, unsigned long nr_file,
struct list_head *page_list)
{
struct page *page;
struct pagevec pvec;
+ struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc);
pagevec_init(&pvec, 1);
@@ -1200,6 +1202,37 @@
pagevec_release(&pvec);
}
+static noinline_for_stack void update_isolated_counts(struct zone *zone,
+ struct scan_control *sc,
+ unsigned long *nr_anon,
+ unsigned long *nr_file,
+ struct list_head *isolated_list)
+{
+ unsigned long nr_active;
+ unsigned int count[NR_LRU_LISTS] = { 0, };
+ struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc);
+
+ nr_active = clear_active_flags(isolated_list, count);
+ __count_vm_events(PGDEACTIVATE, nr_active);
+
+ __mod_zone_page_state(zone, NR_ACTIVE_FILE,
+ -count[LRU_ACTIVE_FILE]);
+ __mod_zone_page_state(zone, NR_INACTIVE_FILE,
+ -count[LRU_INACTIVE_FILE]);
+ __mod_zone_page_state(zone, NR_ACTIVE_ANON,
+ -count[LRU_ACTIVE_ANON]);
+ __mod_zone_page_state(zone, NR_INACTIVE_ANON,
+ -count[LRU_INACTIVE_ANON]);
+
+ *nr_anon = count[LRU_ACTIVE_ANON] + count[LRU_INACTIVE_ANON];
+ *nr_file = count[LRU_ACTIVE_FILE] + count[LRU_INACTIVE_FILE];
+ __mod_zone_page_state(zone, NR_ISOLATED_ANON, *nr_anon);
+ __mod_zone_page_state(zone, NR_ISOLATED_FILE, *nr_file);
+
+ reclaim_stat->recent_scanned[0] += *nr_anon;
+ reclaim_stat->recent_scanned[1] += *nr_file;
+}
+
/*
* shrink_inactive_list() is a helper for shrink_zone(). It returns the number
* of reclaimed pages
@@ -1211,10 +1244,8 @@
LIST_HEAD(page_list);
unsigned long nr_scanned;
unsigned long nr_reclaimed = 0;
- struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc);
unsigned long nr_taken;
unsigned long nr_active;
- unsigned int count[NR_LRU_LISTS] = { 0, };
unsigned long nr_anon;
unsigned long nr_file;
@@ -1261,25 +1292,7 @@
return 0;
}
- nr_active = clear_active_flags(&page_list, count);
- __count_vm_events(PGDEACTIVATE, nr_active);
-
- __mod_zone_page_state(zone, NR_ACTIVE_FILE,
- -count[LRU_ACTIVE_FILE]);
- __mod_zone_page_state(zone, NR_INACTIVE_FILE,
- -count[LRU_INACTIVE_FILE]);
- __mod_zone_page_state(zone, NR_ACTIVE_ANON,
- -count[LRU_ACTIVE_ANON]);
- __mod_zone_page_state(zone, NR_INACTIVE_ANON,
- -count[LRU_INACTIVE_ANON]);
-
- nr_anon = count[LRU_ACTIVE_ANON] + count[LRU_INACTIVE_ANON];
- nr_file = count[LRU_ACTIVE_FILE] + count[LRU_INACTIVE_FILE];
- __mod_zone_page_state(zone, NR_ISOLATED_ANON, nr_anon);
- __mod_zone_page_state(zone, NR_ISOLATED_FILE, nr_file);
-
- reclaim_stat->recent_scanned[0] += nr_anon;
- reclaim_stat->recent_scanned[1] += nr_file;
+ update_isolated_counts(zone, sc, &nr_anon, &nr_file, &page_list);
spin_unlock_irq(&zone->lru_lock);
@@ -1299,7 +1312,7 @@
* The attempt at page out may have made some
* of the pages active, mark them inactive again.
*/
- nr_active = clear_active_flags(&page_list, count);
+ nr_active = clear_active_flags(&page_list, NULL);
count_vm_events(PGDEACTIVATE, nr_active);
nr_reclaimed += shrink_page_list(&page_list, sc, PAGEOUT_IO_SYNC);
@@ -1310,7 +1323,7 @@
__count_vm_events(KSWAPD_STEAL, nr_reclaimed);
__count_zone_vm_events(PGSTEAL, zone, nr_reclaimed);
- putback_lru_pages(zone, reclaim_stat, nr_anon, nr_file, &page_list);
+ putback_lru_pages(zone, sc, nr_anon, nr_file, &page_list);
return nr_reclaimed;
}