diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/page_alloc.c | 63 |
1 files changed, 32 insertions, 31 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 38ad6dd..dea406a 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3260,6 +3260,8 @@ should_compact_retry(unsigned int order, enum compact_result compact_result, enum migrate_mode *migrate_mode, int compaction_retries) { + int max_retries = MAX_COMPACT_RETRIES; + if (!order) return false; @@ -3277,17 +3279,24 @@ should_compact_retry(unsigned int order, enum compact_result compact_result, } /* - * !costly allocations are really important and we have to make sure - * the compaction wasn't deferred or didn't bail out early due to locks - * contention before we go OOM. Still cap the reclaim retry loops with - * progress to prevent from looping forever and potential trashing. + * 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. */ - if (order <= PAGE_ALLOC_COSTLY_ORDER) { - if (compaction_withdrawn(compact_result)) - return true; - if (compaction_retries <= MAX_COMPACT_RETRIES) - return true; - } + if (compaction_withdrawn(compact_result)) + return true; + + /* + * !costly requests are much more important than __GFP_REPEAT + * costly ones because they are de facto nofail and invoke OOM + * killer to move on while costly can fail and users are ready + * to cope with that. 1/4 retries is rather arbitrary but we + * would need much more detailed feedback from compaction to + * make a better decision. + */ + if (order > PAGE_ALLOC_COSTLY_ORDER) + max_retries /= 4; + if (compaction_retries <= max_retries) + return true; return false; } @@ -3449,18 +3458,17 @@ static inline bool is_thp_gfp_mask(gfp_t gfp_mask) * Checks whether it makes sense to retry the reclaim to make a forward progress * for the given allocation request. * The reclaim feedback represented by did_some_progress (any progress during - * the last reclaim round), pages_reclaimed (cumulative number of reclaimed - * pages) and no_progress_loops (number of reclaim rounds without any progress - * in a row) is considered as well as the reclaimable pages on the applicable - * zone list (with a backoff mechanism which is a function of no_progress_loops). + * the last reclaim round) and no_progress_loops (number of reclaim rounds without + * any progress in a row) is considered as well as the reclaimable pages on the + * applicable zone list (with a backoff mechanism which is a function of + * no_progress_loops). * * Returns true if a retry is viable or false to enter the oom path. */ static inline bool should_reclaim_retry(gfp_t gfp_mask, unsigned order, struct alloc_context *ac, int alloc_flags, - bool did_some_progress, unsigned long pages_reclaimed, - int no_progress_loops) + bool did_some_progress, int no_progress_loops) { struct zone *zone; struct zoneref *z; @@ -3472,14 +3480,6 @@ should_reclaim_retry(gfp_t gfp_mask, unsigned order, if (no_progress_loops > MAX_RECLAIM_RETRIES) return false; - if (order > PAGE_ALLOC_COSTLY_ORDER) { - if (pages_reclaimed >= (1<<order)) - return false; - - if (did_some_progress) - return true; - } - /* * Keep reclaiming pages while there is a chance this will lead somewhere. * If none of the target zones can satisfy our allocation request even @@ -3550,7 +3550,6 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, bool can_direct_reclaim = gfp_mask & __GFP_DIRECT_RECLAIM; struct page *page = NULL; unsigned int alloc_flags; - unsigned long pages_reclaimed = 0; unsigned long did_some_progress; enum migrate_mode migration_mode = MIGRATE_ASYNC; enum compact_result compact_result; @@ -3686,16 +3685,18 @@ retry: if (order > PAGE_ALLOC_COSTLY_ORDER && !(gfp_mask & __GFP_REPEAT)) goto noretry; - if (did_some_progress) { + /* + * Costly allocations might have made a progress but this doesn't mean + * their order will become available due to high fragmentation so + * always increment the no progress counter for them + */ + if (did_some_progress && order <= PAGE_ALLOC_COSTLY_ORDER) no_progress_loops = 0; - pages_reclaimed += did_some_progress; - } else { + else no_progress_loops++; - } if (should_reclaim_retry(gfp_mask, order, ac, alloc_flags, - did_some_progress > 0, pages_reclaimed, - no_progress_loops)) + did_some_progress > 0, no_progress_loops)) goto retry; /* |