diff options
Diffstat (limited to 'mm/compaction.c')
| -rw-r--r-- | mm/compaction.c | 32 |
1 files changed, 25 insertions, 7 deletions
diff --git a/mm/compaction.c b/mm/compaction.c index 21bf292b642a..1c7195d42e83 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -1125,27 +1125,26 @@ int sysctl_extfrag_threshold = 500; * @nodemask: The allowed nodes to allocate from * @mode: The migration mode for async, sync light, or sync migration * @contended: Return value that is true if compaction was aborted due to lock contention - * @page: Optionally capture a free page of the requested order during compaction + * @candidate_zone: Return the zone where we think allocation should succeed * * This is the main entry point for direct page compaction. */ unsigned long try_to_compact_pages(struct zonelist *zonelist, int order, gfp_t gfp_mask, nodemask_t *nodemask, - enum migrate_mode mode, bool *contended) + enum migrate_mode mode, bool *contended, + struct zone **candidate_zone) { enum zone_type high_zoneidx = gfp_zone(gfp_mask); int may_enter_fs = gfp_mask & __GFP_FS; int may_perform_io = gfp_mask & __GFP_IO; struct zoneref *z; struct zone *zone; - int rc = COMPACT_SKIPPED; + int rc = COMPACT_DEFERRED; int alloc_flags = 0; /* Check if the GFP flags allow compaction */ if (!order || !may_enter_fs || !may_perform_io) - return rc; - - count_compact_event(COMPACTSTALL); + return COMPACT_SKIPPED; #ifdef CONFIG_CMA if (allocflags_to_migratetype(gfp_mask) == MIGRATE_MOVABLE) @@ -1156,14 +1155,33 @@ unsigned long try_to_compact_pages(struct zonelist *zonelist, nodemask) { int status; + if (compaction_deferred(zone, order)) + continue; + status = compact_zone_order(zone, order, gfp_mask, mode, contended); rc = max(status, rc); /* If a normal allocation would succeed, stop compacting */ if (zone_watermark_ok(zone, order, low_wmark_pages(zone), 0, - alloc_flags)) + alloc_flags)) { + *candidate_zone = zone; + /* + * We think the allocation will succeed in this zone, + * but it is not certain, hence the false. The caller + * will repeat this with true if allocation indeed + * succeeds in this zone. + */ + compaction_defer_reset(zone, order, false); break; + } else if (mode != MIGRATE_ASYNC) { + /* + * We think that allocation won't succeed in this zone + * so we defer compaction there. If it ends up + * succeeding after all, it will be reset. + */ + defer_compaction(zone, order); + } } return rc; |