diff --git a/include/linux/compaction.h b/include/linux/compaction.h index 9569e7c786d3..4b898cdbdf05 100644 --- a/include/linux/compaction.h +++ b/include/linux/compaction.h @@ -129,11 +129,8 @@ static inline bool compaction_failed(enum compact_result result) return false; } -/* - * Compaction has backed off for some reason. It might be throttling or - * lock contention. Retrying is still worthwhile. - */ -static inline bool compaction_withdrawn(enum compact_result result) +/* Compaction needs reclaim to be performed first, so it can continue. */ +static inline bool compaction_needs_reclaim(enum compact_result result) { /* * Compaction backed off due to watermark checks for order-0 @@ -142,6 +139,16 @@ static inline bool compaction_withdrawn(enum compact_result result) if (result == COMPACT_SKIPPED) return true; + return false; +} + +/* + * Compaction has backed off for some reason after doing some work or none + * at all. It might be throttling or lock contention. Retrying might be still + * worthwhile, but with a higher priority if allowed. + */ +static inline bool compaction_withdrawn(enum compact_result result) +{ /* * If compaction is deferred for high-order allocations, it is * because sync compaction recently failed. If this is the case @@ -207,6 +214,11 @@ static inline bool compaction_failed(enum compact_result result) return false; } +static inline bool compaction_needs_reclaim(enum compact_result result) +{ + return false; +} + static inline bool compaction_withdrawn(enum compact_result result) { return true; diff --git a/mm/page_alloc.c b/mm/page_alloc.c index df566c0f6729..591e026534c2 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3955,16 +3955,24 @@ should_compact_retry(struct alloc_context *ac, int order, int alloc_flags, goto check_priority; /* - * make sure the compaction wasn't deferred or didn't bail out early - * due to locks contention before we declare that we should give up. - * But do not retry if the given zonelist is not suitable for - * compaction. + * compaction was skipped because there are not enough order-0 pages + * to work with, so we retry only if it looks like reclaim can help. */ - if (compaction_withdrawn(compact_result)) { + if (compaction_needs_reclaim(compact_result)) { ret = compaction_zonelist_suitable(ac, order, alloc_flags); goto out; } + /* + * make sure the compaction wasn't deferred or didn't bail out early + * due to locks contention before we declare that we should give up. + * But the next retry should use a higher priority if allowed, so + * we don't just keep bailing out endlessly. + */ + if (compaction_withdrawn(compact_result)) { + goto check_priority; + } + /* * !costly requests are much more important than __GFP_RETRY_MAYFAIL * costly ones because they are de facto nofail and invoke OOM