Fix the execution order issue in alloc_contig_range_noprof where drain_all_pages was called after start_isolate_page_range, which may be lead to race conditions. Based on community patches commit ec6e8c7e0314 ("mm, page_alloc: disable pcplists during memory offline") and commit d479960e44f27 ("mm: disable LRU pagevec during the migration temporarily"), we disable pcplists and LRU cache before page isolation to ensure no pages are left in per-cpu lists during isolation. Signed-off-by: Hua Su Signed-off-by: Hua Su --- mm/page_alloc.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 6a47443c48ff..d08f929ca64c 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -6815,8 +6815,6 @@ static int __alloc_contig_migrate_range(struct compact_control *cc, .reason = MR_CONTIG_RANGE, }; - lru_cache_disable(); - while (pfn < end || !list_empty(&cc->migratepages)) { if (fatal_signal_pending(current)) { ret = -EINTR; @@ -6850,7 +6848,6 @@ static int __alloc_contig_migrate_range(struct compact_control *cc, break; } - lru_cache_enable(); if (ret < 0) { if (!(cc->gfp_mask & __GFP_NOWARN) && ret == -EBUSY) alloc_contig_dump_pages(&cc->migratepages); @@ -6973,6 +6970,9 @@ int alloc_contig_range_noprof(unsigned long start, unsigned long end, if (__alloc_contig_verify_gfp_mask(gfp_mask, (gfp_t *)&cc.gfp_mask)) return -EINVAL; + zone_pcp_disable(cc.zone); + lru_cache_disable(); + /* * What we do here is we mark all pageblocks in range as * MIGRATE_ISOLATE. Because pageblock and max order pages may @@ -6998,8 +6998,6 @@ int alloc_contig_range_noprof(unsigned long start, unsigned long end, if (ret) goto done; - drain_all_pages(cc.zone); - /* * In case of -EBUSY, we'd like to know which page causes problem. * So, just fall through. test_pages_isolated() has a tracepoint @@ -7076,6 +7074,8 @@ int alloc_contig_range_noprof(unsigned long start, unsigned long end, start, end, outer_start, outer_end); } done: + lru_cache_enable(); + zone_pcp_enable(cc.zone); undo_isolate_page_range(start, end); return ret; } -- 2.34.1