mm: filter based on a nodemask as well as a gfp_mask

The MPOL_BIND policy creates a zonelist that is used for allocations
controlled by that mempolicy.  As the per-node zonelist is already being
filtered based on a zone id, this patch adds a version of __alloc_pages() that
takes a nodemask for further filtering.  This eliminates the need for
MPOL_BIND to create a custom zonelist.

A positive benefit of this is that allocations using MPOL_BIND now use the
local node's distance-ordered zonelist instead of a custom node-id-ordered
zonelist.  I.e., pages will be allocated from the closest allowed node with
available memory.

[Lee.Schermerhorn@hp.com: Mempolicy: update stale documentation and comments]
[Lee.Schermerhorn@hp.com: Mempolicy: make dequeue_huge_page_vma() obey MPOL_BIND nodemask]
[Lee.Schermerhorn@hp.com: Mempolicy: make dequeue_huge_page_vma() obey MPOL_BIND nodemask rework]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 2 deletions

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 4bced0d705ca..3737d82f5225 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -95,12 +95,14 @@ static struct page *dequeue_huge_page_vma(struct vm_area_struct *vma,
         int nid;
         struct page *page = NULL;
         struct mempolicy *mpol;
+        nodemask_t *nodemask;
         struct zonelist *zonelist = huge_zonelist(vma, address,
-                                        htlb_alloc_mask, &mpol);
+                                        htlb_alloc_mask, &mpol, &nodemask);
         struct zone *zone;
         struct zoneref *z;
 
-        for_each_zone_zonelist(zone, z, zonelist, MAX_NR_ZONES - 1) {
+        for_each_zone_zonelist_nodemask(zone, z, zonelist,
+                                                MAX_NR_ZONES - 1, nodemask) {
                 nid = zone_to_nid(zone);
                 if (cpuset_zone_allowed_softwall(zone, htlb_alloc_mask) &&
                     !list_empty(&hugepage_freelists[nid])) {