diff options
Diffstat (limited to 'mm/vmscan.c')
| -rw-r--r-- | mm/vmscan.c | 66 |
1 files changed, 47 insertions, 19 deletions
diff --git a/mm/vmscan.c b/mm/vmscan.c index 99b434b674c0..be5a9c15f557 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2176,9 +2176,12 @@ 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; @@ -2193,13 +2196,20 @@ 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); @@ -2215,12 +2225,20 @@ 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, @@ -2242,13 +2260,12 @@ 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, @@ -2366,6 +2383,19 @@ static void age_active_anon(struct zone *zone, struct scan_control *sc) } while (memcg); } +static bool zone_balanced(struct zone *zone, int order, + unsigned long balance_gap, int classzone_idx) +{ + if (!zone_watermark_ok_safe(zone, order, high_wmark_pages(zone) + + balance_gap, classzone_idx, 0)) + return false; + + if (COMPACTION_BUILD && order && !compaction_suitable(zone, order)) + return false; + + return true; +} + /* * pgdat_balanced is used when checking if a node is balanced for high-order * allocations. Only zones that meet watermarks and are in a zone allowed @@ -2444,8 +2474,7 @@ static bool prepare_kswapd_sleep(pg_data_t *pgdat, int order, long remaining, continue; } - if (!zone_watermark_ok_safe(zone, order, high_wmark_pages(zone), - i, 0)) + if (!zone_balanced(zone, order, 0, i)) all_zones_ok = false; else balanced += zone->present_pages; @@ -2554,8 +2583,7 @@ loop_again: break; } - if (!zone_watermark_ok_safe(zone, order, - high_wmark_pages(zone), 0, 0)) { + if (!zone_balanced(zone, order, 0, 0)) { end_zone = i; break; } else { @@ -2631,9 +2659,8 @@ loop_again: testorder = 0; if ((buffer_heads_over_limit && is_highmem_idx(i)) || - !zone_watermark_ok_safe(zone, testorder, - high_wmark_pages(zone) + balance_gap, - end_zone, 0)) { + !zone_balanced(zone, testorder, + balance_gap, end_zone)) { shrink_zone(zone, &sc); reclaim_state->reclaimed_slab = 0; @@ -2660,8 +2687,7 @@ loop_again: continue; } - if (!zone_watermark_ok_safe(zone, testorder, - high_wmark_pages(zone), end_zone, 0)) { + if (!zone_balanced(zone, testorder, 0, end_zone)) { all_zones_ok = 0; /* * We are still under min water mark. This @@ -2953,6 +2979,8 @@ static int kswapd(void *p) &balanced_classzone_idx); } } + + current->reclaim_state = NULL; return 0; } |