Merge branch 'master' of /usr/src/ntfs-2.6/

1 files changed, 25 insertions, 15 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 1731236dec35..3b21a13d841c 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -773,9 +773,12 @@ again:
 }
 
 #define ALLOC_NO_WATERMARKS     0x01 /* don't check watermarks at all */
-#define ALLOC_HARDER            0x02 /* try to alloc harder */
-#define ALLOC_HIGH              0x04 /* __GFP_HIGH set */
-#define ALLOC_CPUSET            0x08 /* check for correct cpuset */
+#define ALLOC_WMARK_MIN         0x02 /* use pages_min watermark */
+#define ALLOC_WMARK_LOW         0x04 /* use pages_low watermark */
+#define ALLOC_WMARK_HIGH        0x08 /* use pages_high watermark */
+#define ALLOC_HARDER            0x10 /* try to alloc harder */
+#define ALLOC_HIGH              0x20 /* __GFP_HIGH set */
+#define ALLOC_CPUSET            0x40 /* check for correct cpuset */
 
 /*
  * Return 1 if free pages are above 'mark'. This takes into account the order
@@ -830,7 +833,14 @@ get_page_from_freelist(gfp_t gfp_mask, unsigned int order,
                         continue;
 
                 if (!(alloc_flags & ALLOC_NO_WATERMARKS)) {
-                        if (!zone_watermark_ok(*z, order, (*z)->pages_low,
+                        unsigned long mark;
+                        if (alloc_flags & ALLOC_WMARK_MIN)
+                                mark = (*z)->pages_min;
+                        else if (alloc_flags & ALLOC_WMARK_LOW)
+                                mark = (*z)->pages_low;
+                        else
+                                mark = (*z)->pages_high;
+                        if (!zone_watermark_ok(*z, order, mark,
                                     classzone_idx, alloc_flags))
                                 continue;
                 }
@@ -871,7 +881,7 @@ restart:
         }
 
         page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, order,
-                                zonelist, ALLOC_CPUSET);
+                                zonelist, ALLOC_WMARK_LOW|ALLOC_CPUSET);
         if (page)
                 goto got_pg;
 
@@ -888,7 +898,7 @@ restart:
          * cannot run direct reclaim, or if the caller has realtime scheduling
          * policy.
          */
-        alloc_flags = 0;
+        alloc_flags = ALLOC_WMARK_MIN;
         if ((unlikely(rt_task(p)) && !in_interrupt()) || !wait)
                 alloc_flags |= ALLOC_HARDER;
         if (gfp_mask & __GFP_HIGH)
@@ -959,7 +969,7 @@ rebalance:
                  * under heavy pressure.
                  */
                 page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, order,
-                                                zonelist, ALLOC_CPUSET);
+                                zonelist, ALLOC_WMARK_HIGH|ALLOC_CPUSET);
                 if (page)
                         goto got_pg;
 
@@ -1762,16 +1772,16 @@ static int __devinit zone_batchsize(struct zone *zone)
                 batch = 1;
 
         /*
-         * We will be trying to allcoate bigger chunks of contiguous
-         * memory of the order of fls(batch).  This should result in
-         * better cache coloring.
+         * Clamp the batch to a 2^n - 1 value. Having a power
+         * of 2 value was found to be more likely to have
+         * suboptimal cache aliasing properties in some cases.
          *
-         * A sanity check also to ensure that batch is still in limits.
+         * For example if 2 tasks are alternately allocating
+         * batches of pages, one task can end up with a lot
+         * of pages of one half of the possible page colors
+         * and the other with pages of the other colors.
          */
-        batch = (1 << fls(batch + batch/2));
-
-        if (fls(batch) >= (PAGE_SHIFT + MAX_ORDER - 2))
-                batch = PAGE_SHIFT + ((MAX_ORDER - 1 - PAGE_SHIFT)/2);
+        batch = (1 << (fls(batch + batch/2)-1)) - 1;
 
         return batch;
 }