[PATCH] zone reclaim: do not check references to a page during zone reclaim
shrink_list() and refill_inactive() check all ptes pointing to a page for
reference bits in order to decide if the page should be put on the active
list. This is not necessary for zone_reclaim since we are only interested
in removing unmapped pages. Skip the checks in both functions.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 5db32fd..e1c6423 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -443,6 +443,10 @@
BUG_ON(PageActive(page));
sc->nr_scanned++;
+
+ if (!sc->may_swap && page_mapped(page))
+ goto keep_locked;
+
/* Double the slab pressure for mapped and swapcache pages */
if (page_mapped(page) || PageSwapCache(page))
sc->nr_scanned++;
@@ -1231,7 +1235,7 @@
* Now use this metric to decide whether to start moving mapped memory
* onto the inactive list.
*/
- if (swap_tendency >= 100)
+ if (swap_tendency >= 100 && sc->may_swap)
reclaim_mapped = 1;
while (!list_empty(&l_hold)) {