1 files changed, 27 insertions, 10 deletions

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 48550c66f1f2..cbf84e152f04 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2207,9 +2207,12 @@ static bool pfmemalloc_watermark_ok(pg_data_t *pgdat)
  * Throttle direct reclaimers if backing storage is backed by the network
  * and the PFMEMALLOC reserve for the preferred node is getting dangerously
  * depleted. kswapd will continue to make progress and wake the processes
- * when the low watermark is reached
+ * when the low watermark is reached.
+ *
+ * Returns true if a fatal signal was delivered during throttling. If this
+ * happens, the page allocator should not consider triggering the OOM killer.
  */
-static void throttle_direct_reclaim(gfp_t gfp_mask, struct zonelist *zonelist,
+static bool throttle_direct_reclaim(gfp_t gfp_mask, struct zonelist *zonelist,
                                         nodemask_t *nodemask)
 {
         struct zone *zone;
@@ -2224,13 +2227,20 @@ static void throttle_direct_reclaim(gfp_t gfp_mask, struct zonelist *zonelist,
          * processes to block on log_wait_commit().
          */
         if (current->flags & PF_KTHREAD)
-                return;
+                goto out;
+
+        /*
+         * If a fatal signal is pending, this process should not throttle.
+         * It should return quickly so it can exit and free its memory
+         */
+        if (fatal_signal_pending(current))
+                goto out;
 
         /* Check if the pfmemalloc reserves are ok */
         first_zones_zonelist(zonelist, high_zoneidx, NULL, &zone);
         pgdat = zone->zone_pgdat;
         if (pfmemalloc_watermark_ok(pgdat))
-                return;
+                goto out;
 
         /* Account for the throttling */
         count_vm_event(PGSCAN_DIRECT_THROTTLE);
@@ -2246,12 +2256,20 @@ static void throttle_direct_reclaim(gfp_t gfp_mask, struct zonelist *zonelist,
         if (!(gfp_mask & __GFP_FS)) {
                 wait_event_interruptible_timeout(pgdat->pfmemalloc_wait,
                         pfmemalloc_watermark_ok(pgdat), HZ);
-                return;
+
+                goto check_pending;
         }
 
         /* Throttle until kswapd wakes the process */
         wait_event_killable(zone->zone_pgdat->pfmemalloc_wait,
                 pfmemalloc_watermark_ok(pgdat));
+
+check_pending:
+        if (fatal_signal_pending(current))
+                return true;
+
+out:
+        return false;
 }
 
 unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
@@ -2273,13 +2291,12 @@ unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
                 .gfp_mask = sc.gfp_mask,
         };
 
-        throttle_direct_reclaim(gfp_mask, zonelist, nodemask);
-
         /*
-         * Do not enter reclaim if fatal signal is pending. 1 is returned so
-         * that the page allocator does not consider triggering OOM
+         * Do not enter reclaim if fatal signal was delivered while throttled.
+         * 1 is returned so that the page allocator does not OOM kill at this
+         * point.
          */
-        if (fatal_signal_pending(current))
+        if (throttle_direct_reclaim(gfp_mask, zonelist, nodemask))
                 return 1;
 
         trace_mm_vmscan_direct_reclaim_begin(order,