1 files changed, 35 insertions, 47 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 7633c503a116..8e20f9c2fa5a 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2332,12 +2332,21 @@ static inline struct page *
 __alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order,
         struct zonelist *zonelist, enum zone_type high_zoneidx,
         nodemask_t *nodemask, struct zone *preferred_zone,
-        int classzone_idx, int migratetype)
+        int classzone_idx, int migratetype, unsigned long *did_some_progress)
 {
         struct page *page;
 
-        /* Acquire the per-zone oom lock for each zone */
+        *did_some_progress = 0;
+
+        if (oom_killer_disabled)
+                return NULL;
+
+        /*
+         * Acquire the per-zone oom lock for each zone.  If that
+         * fails, somebody else is making progress for us.
+         */
         if (!oom_zonelist_trylock(zonelist, gfp_mask)) {
+                *did_some_progress = 1;
                 schedule_timeout_uninterruptible(1);
                 return NULL;
         }
@@ -2363,12 +2372,18 @@ __alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order,
                 goto out;
 
         if (!(gfp_mask & __GFP_NOFAIL)) {
+                /* Coredumps can quickly deplete all memory reserves */
+                if (current->flags & PF_DUMPCORE)
+                        goto out;
                 /* The OOM killer will not help higher order allocs */
                 if (order > PAGE_ALLOC_COSTLY_ORDER)
                         goto out;
                 /* The OOM killer does not needlessly kill tasks for lowmem */
                 if (high_zoneidx < ZONE_NORMAL)
                         goto out;
+                /* The OOM killer does not compensate for light reclaim */
+                if (!(gfp_mask & __GFP_FS))
+                        goto out;
                 /*
                  * GFP_THISNODE contains __GFP_NORETRY and we never hit this.
                  * Sanity check for bare calls of __GFP_THISNODE, not real OOM.
@@ -2381,7 +2396,7 @@ __alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order,
         }
         /* Exhausted what can be done so it's blamo time */
         out_of_memory(zonelist, gfp_mask, order, nodemask, false);
-
+        *did_some_progress = 1;
 out:
         oom_zonelist_unlock(zonelist, gfp_mask);
         return page;
@@ -2658,7 +2673,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
             (gfp_mask & GFP_THISNODE) == GFP_THISNODE)
                 goto nopage;
 
-restart:
+retry:
         if (!(gfp_mask & __GFP_NO_KSWAPD))
                 wake_all_kswapds(order, zonelist, high_zoneidx,
                                 preferred_zone, nodemask);
@@ -2681,7 +2696,6 @@ restart:
                 classzone_idx = zonelist_zone_idx(preferred_zoneref);
         }
 
-rebalance:
         /* This is the last chance, in general, before the goto nopage. */
         page = get_page_from_freelist(gfp_mask, nodemask, order, zonelist,
                         high_zoneidx, alloc_flags & ~ALLOC_NO_WATERMARKS,
@@ -2788,54 +2802,28 @@ rebalance:
         if (page)
                 goto got_pg;
 
-        /*
-         * If we failed to make any progress reclaiming, then we are
-         * running out of options and have to consider going OOM
-         */
-        if (!did_some_progress) {
-                if (oom_gfp_allowed(gfp_mask)) {
-                        if (oom_killer_disabled)
-                                goto nopage;
-                        /* Coredumps can quickly deplete all memory reserves */
-                        if ((current->flags & PF_DUMPCORE) &&
-                            !(gfp_mask & __GFP_NOFAIL))
-                                goto nopage;
-                        page = __alloc_pages_may_oom(gfp_mask, order,
-                                        zonelist, high_zoneidx,
-                                        nodemask, preferred_zone,
-                                        classzone_idx, migratetype);
-                        if (page)
-                                goto got_pg;
-
-                        if (!(gfp_mask & __GFP_NOFAIL)) {
-                                /*
-                                 * The oom killer is not called for high-order
-                                 * allocations that may fail, so if no progress
-                                 * is being made, there are no other options and
-                                 * retrying is unlikely to help.
-                                 */
-                                if (order > PAGE_ALLOC_COSTLY_ORDER)
-                                        goto nopage;
-                                /*
-                                 * The oom killer is not called for lowmem
-                                 * allocations to prevent needlessly killing
-                                 * innocent tasks.
-                                 */
-                                if (high_zoneidx < ZONE_NORMAL)
-                                        goto nopage;
-                        }
-
-                        goto restart;
-                }
-        }
-
         /* Check if we should retry the allocation */
         pages_reclaimed += did_some_progress;
         if (should_alloc_retry(gfp_mask, order, did_some_progress,
                                                 pages_reclaimed)) {
+                /*
+                 * If we fail to make progress by freeing individual
+                 * pages, but the allocation wants us to keep going,
+                 * start OOM killing tasks.
+                 */
+                if (!did_some_progress) {
+                        page = __alloc_pages_may_oom(gfp_mask, order, zonelist,
+                                                high_zoneidx, nodemask,
+                                                preferred_zone, classzone_idx,
+                                                migratetype,&did_some_progress);
+                        if (page)
+                                goto got_pg;
+                        if (!did_some_progress)
+                                goto nopage;
+                }
                 /* Wait for some write requests to complete then retry */
                 wait_iff_congested(preferred_zone, BLK_RW_ASYNC, HZ/50);
-                goto rebalance;
+                goto retry;
         } else {
                 /*
                  * High-order allocations do not necessarily loop after