diff options
Diffstat (limited to 'mm/compaction.c')
| -rw-r--r-- | mm/compaction.c | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/mm/compaction.c b/mm/compaction.c index e5995f38d677..cd93ea24c565 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -1438,6 +1438,11 @@ bool compaction_zonelist_suitable(struct alloc_context *ac, int order, { struct zone *zone; struct zoneref *z; + pg_data_t *last_pgdat = NULL; + + /* Do not retry compaction for zone-constrained allocations */ + if (ac->high_zoneidx < ZONE_NORMAL) + return false; /* * Make sure at least one zone would pass __compaction_suitable if we continue @@ -1448,14 +1453,27 @@ bool compaction_zonelist_suitable(struct alloc_context *ac, int order, unsigned long available; enum compact_result compact_result; + if (last_pgdat == zone->zone_pgdat) + continue; + + /* + * This over-estimates the number of pages available for + * reclaim/compaction but walking the LRU would take too + * long. The consequences are that compaction may retry + * longer than it should for a zone-constrained allocation + * request. + */ + last_pgdat = zone->zone_pgdat; + available = pgdat_reclaimable_pages(zone->zone_pgdat) / order; + /* * Do not consider all the reclaimable memory because we do not * want to trash just for a single high order allocation which * is even not guaranteed to appear even if __compaction_suitable * is happy about the watermark check. */ - available = zone_reclaimable_pages(zone) / order; available += zone_page_state_snapshot(zone, NR_FREE_PAGES); + available = min(zone->managed_pages, available); compact_result = __compaction_suitable(zone, order, alloc_flags, ac_classzone_idx(ac), available); if (compact_result != COMPACT_SKIPPED && |