diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/page_alloc.c | 14 | ||||
| -rw-r--r-- | mm/vmscan.c | 32 |
2 files changed, 31 insertions, 15 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index f6005b7c3446..02c1a60d7937 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3805,16 +3805,18 @@ retry: return page; } -static void wake_all_kswapds(unsigned int order, const struct alloc_context *ac) +static void wake_all_kswapds(unsigned int order, gfp_t gfp_mask, + const struct alloc_context *ac) { struct zoneref *z; struct zone *zone; pg_data_t *last_pgdat = NULL; + enum zone_type high_zoneidx = ac->high_zoneidx; - for_each_zone_zonelist_nodemask(zone, z, ac->zonelist, - ac->high_zoneidx, ac->nodemask) { + for_each_zone_zonelist_nodemask(zone, z, ac->zonelist, high_zoneidx, + ac->nodemask) { if (last_pgdat != zone->zone_pgdat) - wakeup_kswapd(zone, order, ac->high_zoneidx); + wakeup_kswapd(zone, gfp_mask, order, high_zoneidx); last_pgdat = zone->zone_pgdat; } } @@ -4093,7 +4095,7 @@ retry_cpuset: goto nopage; if (gfp_mask & __GFP_KSWAPD_RECLAIM) - wake_all_kswapds(order, ac); + wake_all_kswapds(order, gfp_mask, ac); /* * The adjusted alloc_flags might result in immediate success, so try @@ -4151,7 +4153,7 @@ retry_cpuset: retry: /* Ensure kswapd doesn't accidentally go to sleep as long as we loop */ if (gfp_mask & __GFP_KSWAPD_RECLAIM) - wake_all_kswapds(order, ac); + wake_all_kswapds(order, gfp_mask, ac); reserve_flags = __gfp_pfmemalloc_flags(gfp_mask); if (reserve_flags) diff --git a/mm/vmscan.c b/mm/vmscan.c index 976be140a8ce..4390a8d5be41 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -3539,16 +3539,21 @@ kswapd_try_sleep: } /* - * A zone is low on free memory, so wake its kswapd task to service it. + * A zone is low on free memory or too fragmented for high-order memory. If + * kswapd should reclaim (direct reclaim is deferred), wake it up for the zone's + * pgdat. It will wake up kcompactd after reclaiming memory. If kswapd reclaim + * has failed or is not needed, still wake up kcompactd if only compaction is + * needed. */ -void wakeup_kswapd(struct zone *zone, int order, enum zone_type classzone_idx) +void wakeup_kswapd(struct zone *zone, gfp_t gfp_flags, int order, + enum zone_type classzone_idx) { pg_data_t *pgdat; if (!managed_zone(zone)) return; - if (!cpuset_zone_allowed(zone, GFP_KERNEL | __GFP_HARDWALL)) + if (!cpuset_zone_allowed(zone, gfp_flags)) return; pgdat = zone->zone_pgdat; pgdat->kswapd_classzone_idx = kswapd_classzone_idx(pgdat, @@ -3557,14 +3562,23 @@ void wakeup_kswapd(struct zone *zone, int order, enum zone_type classzone_idx) if (!waitqueue_active(&pgdat->kswapd_wait)) return; - /* Hopeless node, leave it to direct reclaim */ - if (pgdat->kswapd_failures >= MAX_RECLAIM_RETRIES) - return; - - if (pgdat_balanced(pgdat, order, classzone_idx)) + /* Hopeless node, leave it to direct reclaim if possible */ + if (pgdat->kswapd_failures >= MAX_RECLAIM_RETRIES || + pgdat_balanced(pgdat, order, classzone_idx)) { + /* + * There may be plenty of free memory available, but it's too + * fragmented for high-order allocations. Wake up kcompactd + * and rely on compaction_suitable() to determine if it's + * needed. If it fails, it will defer subsequent attempts to + * ratelimit its work. + */ + if (!(gfp_flags & __GFP_DIRECT_RECLAIM)) + wakeup_kcompactd(pgdat, order, classzone_idx); return; + } - trace_mm_vmscan_wakeup_kswapd(pgdat->node_id, classzone_idx, order); + trace_mm_vmscan_wakeup_kswapd(pgdat->node_id, classzone_idx, order, + gfp_flags); wake_up_interruptible(&pgdat->kswapd_wait); } |
