Memoryless nodes: Fix GFP_THISNODE behavior

GFP_THISNODE checks that the zone selected is within the pgdat (node) of the
first zone of a nodelist.  That only works if the node has memory.  A
memoryless node will have its first node on another pgdat (node).

GFP_THISNODE currently will return simply memory on the first pgdat.  Thus it
is returning memory on other nodes.  GFP_THISNODE should fail if there is no
local memory on a node.

Add a new set of zonelists for each node that only contain the nodes that
belong to the zones itself so that no fallback is possible.

Then modify gfp_type to pickup the right zone based on the presence of
__GFP_THISNODE.

Drop the existing GFP_THISNODE checks from the page_allocators hot path.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Acked-by: Nishanth Aravamudan <nacc@us.ibm.com>
Tested-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Acked-by: Bob Picco <bob.picco@hp.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@skynet.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 12 insertions, 5 deletions

diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index bc68dd9a6d41..12a90a191c11 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -98,22 +98,29 @@ struct vm_area_struct;
 
 static inline enum zone_type gfp_zone(gfp_t flags)
 {
+        int base = 0;
+
+#ifdef CONFIG_NUMA
+        if (flags & __GFP_THISNODE)
+                base = MAX_NR_ZONES;
+#endif
+
 #ifdef CONFIG_ZONE_DMA
         if (flags & __GFP_DMA)
-                return ZONE_DMA;
+                return base + ZONE_DMA;
 #endif
 #ifdef CONFIG_ZONE_DMA32
         if (flags & __GFP_DMA32)
-                return ZONE_DMA32;
+                return base + ZONE_DMA32;
 #endif
         if ((flags & (__GFP_HIGHMEM | __GFP_MOVABLE)) ==
                         (__GFP_HIGHMEM | __GFP_MOVABLE))
-                return ZONE_MOVABLE;
+                return base + ZONE_MOVABLE;
 #ifdef CONFIG_HIGHMEM
         if (flags & __GFP_HIGHMEM)
-                return ZONE_HIGHMEM;
+                return base + ZONE_HIGHMEM;
 #endif
-        return ZONE_NORMAL;
+        return base + ZONE_NORMAL;
 }
 
 /*