1 files changed, 63 insertions, 0 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index c54376a09f30..cd88a860f088 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -49,6 +49,7 @@
 #include <linux/debugobjects.h>
 #include <linux/kmemleak.h>
 #include <linux/memory.h>
+#include <linux/compaction.h>
 #include <trace/events/kmem.h>
 #include <linux/ftrace_event.h>
 
@@ -1758,6 +1759,59 @@ out:
         return page;
 }
 
+#ifdef CONFIG_COMPACTION
+/* Try memory compaction for high-order allocations before reclaim */
+static struct page *
+__alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
+        struct zonelist *zonelist, enum zone_type high_zoneidx,
+        nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
+        int migratetype, unsigned long *did_some_progress)
+{
+        struct page *page;
+
+        if (!order)
+                return NULL;
+
+        *did_some_progress = try_to_compact_pages(zonelist, order, gfp_mask,
+                                                                nodemask);
+        if (*did_some_progress != COMPACT_SKIPPED) {
+
+                /* Page migration frees to the PCP lists but we want merging */
+                drain_pages(get_cpu());
+                put_cpu();
+
+                page = get_page_from_freelist(gfp_mask, nodemask,
+                                order, zonelist, high_zoneidx,
+                                alloc_flags, preferred_zone,
+                                migratetype);
+                if (page) {
+                        count_vm_event(COMPACTSUCCESS);
+                        return page;
+                }
+
+                /*
+                 * It's bad if compaction run occurs and fails.
+                 * The most likely reason is that pages exist,
+                 * but not enough to satisfy watermarks.
+                 */
+                count_vm_event(COMPACTFAIL);
+
+                cond_resched();
+        }
+
+        return NULL;
+}
+#else
+static inline struct page *
+__alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
+        struct zonelist *zonelist, enum zone_type high_zoneidx,
+        nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
+        int migratetype, unsigned long *did_some_progress)
+{
+        return NULL;
+}
+#endif /* CONFIG_COMPACTION */
+
 /* The really slow allocator path where we enter direct reclaim */
 static inline struct page *
 __alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order,
@@ -1944,6 +1998,15 @@ rebalance:
         if (test_thread_flag(TIF_MEMDIE) && !(gfp_mask & __GFP_NOFAIL))
                 goto nopage;
 
+        /* Try direct compaction */
+        page = __alloc_pages_direct_compact(gfp_mask, order,
+                                        zonelist, high_zoneidx,
+                                        nodemask,
+                                        alloc_flags, preferred_zone,
+                                        migratetype, &did_some_progress);
+        if (page)
+                goto got_pg;
+
         /* Try direct reclaim and then allocating */
         page = __alloc_pages_direct_reclaim(gfp_mask, order,
                                         zonelist, high_zoneidx,