page allocator: smarter retry of costly-order allocations

[pandora-kernel.git] / mm / page_alloc.c

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 6965be0..0a502e9 100644 (file)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1461,7 +1461,8 @@ __alloc_pages_internal(gfp_t gfp_mask, unsigned int order,
        struct task_struct *p = current;
        int do_retry;
        int alloc_flags;
-       int did_some_progress;
+       unsigned long did_some_progress;
+       unsigned long pages_reclaimed = 0;
 
        might_sleep_if(wait);
 
@@ -1611,15 +1612,26 @@ nofail_alloc:
         * Don't let big-order allocations loop unless the caller explicitly
         * requests that.  Wait for some write requests to complete then retry.
         *
-        * In this implementation, either order <= PAGE_ALLOC_COSTLY_ORDER or
-        * __GFP_REPEAT mean __GFP_NOFAIL, but that may not be true in other
+        * In this implementation, order <= PAGE_ALLOC_COSTLY_ORDER
+        * means __GFP_NOFAIL, but that may not be true in other
         * implementations.
+        *
+        * For order > PAGE_ALLOC_COSTLY_ORDER, if __GFP_REPEAT is
+        * specified, then we retry until we no longer reclaim any pages
+        * (above), or we've reclaimed an order of pages at least as
+        * large as the allocation's order. In both cases, if the
+        * allocation still fails, we stop retrying.
         */
+       pages_reclaimed += did_some_progress;
        do_retry = 0;
        if (!(gfp_mask & __GFP_NORETRY)) {
-               if ((order <= PAGE_ALLOC_COSTLY_ORDER) ||
-                                               (gfp_mask & __GFP_REPEAT))
+               if (order <= PAGE_ALLOC_COSTLY_ORDER) {
                        do_retry = 1;
+               } else {
+                       if (gfp_mask & __GFP_REPEAT &&
+                               pages_reclaimed < (1 << order))
+                                       do_retry = 1;
+               }
                if (gfp_mask & __GFP_NOFAIL)
                        do_retry = 1;
        }