Subject: + mm-compaction-disallow-high-order-page-for-migration-target.patch added to -mm tree To: iamjoonsoo.kim@xxxxxxx,mgorman@xxxxxxx,riel@xxxxxxxxxx,vbabka@xxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Fri, 21 Feb 2014 14:52:52 -0800 The patch titled Subject: mm/compaction: disallow high-order page for migration target has been added to the -mm tree. Its filename is mm-compaction-disallow-high-order-page-for-migration-target.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-compaction-disallow-high-order-page-for-migration-target.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-compaction-disallow-high-order-page-for-migration-target.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Subject: 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.kim@xxxxxxx> Acked-by: Vlastimil Babka <vbabka@xxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxx> Cc: Rik van Riel <riel@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/compaction.c | 15 +++------------ 1 file changed, 3 insertions(+), 12 deletions(-) diff -puN mm/compaction.c~mm-compaction-disallow-high-order-page-for-migration-target mm/compaction.c --- a/mm/compaction.c~mm-compaction-disallow-high-order-page-for-migration-target +++ a/mm/compaction.c @@ -217,21 +217,12 @@ static inline bool compact_trylock_irqsa /* 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 */ _ Patches currently in -mm which might be from iamjoonsoo.kim@xxxxxxx are kthread-ensure-locality-of-task_struct-allocations.patch mm-hugetlb-unify-region-structure-handling.patch mm-hugetlb-improve-cleanup-resv_map-parameters.patch mm-hugetlb-fix-race-in-region-tracking.patch mm-hugetlb-remove-resv_map_put.patch mm-hugetlb-use-vma_resv_map-map-types.patch mm-hugetlb-improve-page-fault-scalability.patch mm-hugetlb-improve-page-fault-scalability-fix.patch mm-hugetlb-mark-some-bootstrap-functions-as-__init.patch mm-compaction-avoid-isolating-pinned-pages.patch mm-compaction-disallow-high-order-page-for-migration-target.patch mm-compaction-do-not-call-suitable_migration_target-on-every-page.patch mm-compaction-change-the-timing-to-check-to-drop-the-spinlock.patch mm-compaction-check-pageblock-suitability-once-per-pageblock.patch mm-compaction-clean-up-code-on-success-of-ballon-isolation.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html