The commit is pushed to "branch-rh7-3.10.0-693.11.6.vz7.42.x-ovz" and will appear at https://src.openvz.org/scm/ovz/vzkernel.git after rh7-3.10.0-693.11.6.vz7.42.4 ------> commit 6fed33655c58e7b9c28cf9728fb27a631a07299d Author: Joonsoo Kim <iamjoonsoo....@lge.com> Date: Wed Jan 31 18:21:53 2018 +0300
ms/mm/compaction: disallow high-order page for migration target Purpose of compaction is to get a high order page. Currently, if we find high-order page while searching migration target page, we break it to order-0 pages and use them as migration target. It is contrary to purpose of compaction, so disallow high-order page to be used for migration target. Additionally, clean-up logic in suitable_migration_target() to simplify the code. There is no functional changes from this clean-up. Signed-off-by: Joonsoo Kim <iamjoonsoo....@lge.com> Acked-by: Vlastimil Babka <vba...@suse.cz> Cc: Mel Gorman <mgor...@suse.de> Cc: Rik van Riel <r...@redhat.com> Signed-off-by: Andrew Morton <a...@linux-foundation.org> Signed-off-by: Linus Torvalds <torva...@linux-foundation.org> (cherry picked from commit 7d348b9ea64db0a315d777ce7d4b06697f946503) Signed-off-by: Andrey Ryabinin <aryabi...@virtuozzo.com> --- mm/compaction.c | 15 +++------------ 1 file changed, 3 insertions(+), 12 deletions(-) diff --git a/mm/compaction.c b/mm/compaction.c index 981e6b601bfe..1faade458d38 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -219,21 +219,12 @@ static inline bool compact_trylock_irqsave(spinlock_t *lock, /* Returns true if the page is within a block suitable for migration to */ static bool suitable_migration_target(struct page *page) { - int migratetype = get_pageblock_migratetype(page); - - /* Don't interfere with memory hot-remove or the min_free_kbytes blocks */ - if (migratetype == MIGRATE_RESERVE) - return false; - - if (is_migrate_isolate(migratetype)) - return false; - - /* If the page is a large free page, then allow migration */ + /* If the page is a large free page, then disallow migration */ if (PageBuddy(page) && page_order(page) >= pageblock_order) - return true; + return false; /* If the block is MIGRATE_MOVABLE or MIGRATE_CMA, allow migration */ - if (migrate_async_suitable(migratetype)) + if (migrate_async_suitable(get_pageblock_migratetype(page))) return true; /* Otherwise skip the block */ _______________________________________________ Devel mailing list Devel@openvz.org https://lists.openvz.org/mailman/listinfo/devel