From: Christoph Lameter <clameter@engr.sgi.com>
Date: Fri, 24 Feb 2006 21:04:22 +0000 (-0800)
Subject: [PATCH] vmscan: fix zone_reclaim
X-Git-Tag: v2.6.16-rc5~30
X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=d4f7796e9b387e471ab0e8ed4e0c2bd616b3c193;p=linux-2.6-omap-h63xx.git

[PATCH] vmscan: fix zone_reclaim

- PF_SWAPWRITE needs to be set for RECLAIM_SWAP to be able to write
  out pages to swap. Currently RECLAIM_SWAP may not do that.

- remove setting nr_reclaimed pages after slab reclaim since the slab shrinking
  code does not use that and the nr_reclaimed pages is just right for the
  intended follow up action.

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 1838c15ca4f..b0af7593d01 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1908,7 +1908,12 @@ int zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
 		sc.swap_cluster_max = SWAP_CLUSTER_MAX;
 
 	cond_resched();
-	p->flags |= PF_MEMALLOC;
+	/*
+	 * We need to be able to allocate from the reserves for RECLAIM_SWAP
+	 * and we also need to be able to write out pages for RECLAIM_WRITE
+	 * and RECLAIM_SWAP.
+	 */
+	p->flags |= PF_MEMALLOC | PF_SWAPWRITE;
 	reclaim_state.reclaimed_slab = 0;
 	p->reclaim_state = &reclaim_state;
 
@@ -1932,11 +1937,10 @@ int zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
 		 * a long time.
 		 */
 		shrink_slab(sc.nr_scanned, gfp_mask, order);
-		sc.nr_reclaimed = 1;    /* Avoid getting the off node timeout */
 	}
 
 	p->reclaim_state = NULL;
-	current->flags &= ~PF_MEMALLOC;
+	current->flags &= ~(PF_MEMALLOC | PF_SWAPWRITE);
 
 	if (sc.nr_reclaimed == 0)
 		zone->last_unsuccessful_zone_reclaim = jiffies;