[PATCH] ZVC: Support NR_SLAB_RECLAIMABLE / NR_SLAB_UNRECLAIMABLE

Remove the atomic counter for slab_reclaim_pages and replace the counter
and NR_SLAB with two ZVC counter that account for unreclaimable and
reclaimable slab pages: NR_SLAB_RECLAIMABLE and NR_SLAB_UNRECLAIMABLE.

Change the check in vmscan.c to refer to to NR_SLAB_RECLAIMABLE.  The
intend seems to be to check for slab pages that could be freed.

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/mmap.c b/mm/mmap.c
index 8507ee9..eea8eef 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -116,7 +116,7 @@
 		 * which are reclaimable, under pressure.  The dentry
 		 * cache and most inode caches should fall into this
 		 */
-		free += atomic_read(&slab_reclaim_pages);
+		free += global_page_state(NR_SLAB_RECLAIMABLE);
 
 		/*
 		 * Leave the last 3% for root