Messages in this thread | | | From | Bartlomiej Zolnierkiewicz <> | Subject | Re: [RFC][PATCH v2] mm/page_alloc: fix freeing of MIGRATE_RESERVE migratetype pages | Date | Thu, 13 Mar 2014 15:37:46 +0100 |
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On Thursday, March 13, 2014 02:25:40 PM Mel Gorman wrote: > On Fri, Feb 14, 2014 at 07:34:17PM +0100, Bartlomiej Zolnierkiewicz wrote: > > Pages allocated from MIGRATE_RESERVE migratetype pageblocks > > are not freed back to MIGRATE_RESERVE migratetype free > > lists in free_pcppages_bulk()->__free_one_page() if we got > > to free_pcppages_bulk() through drain_[zone_]pages(). > > The freeing through free_hot_cold_page() is okay because > > freepage migratetype is set to pageblock migratetype before > > calling free_pcppages_bulk(). If pages of MIGRATE_RESERVE > > migratetype end up on the free lists of other migratetype > > whole Reserved pageblock may be later changed to the other > > migratetype in __rmqueue_fallback() and it will be never > > changed back to be a Reserved pageblock. Fix the issue by > > preserving freepage migratetype as a pageblock migratetype > > (instead of overriding it to the requested migratetype) > > for MIGRATE_RESERVE migratetype pages in rmqueue_bulk(). > > > > The problem was introduced in v2.6.31 by commit ed0ae21 > > ("page allocator: do not call get_pageblock_migratetype() > > more than necessary"). > > > > Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> > > Reported-by: Yong-Taek Lee <ytk.lee@samsung.com> > > Cc: Marek Szyprowski <m.szyprowski@samsung.com> > > Cc: Mel Gorman <mgorman@suse.de> > > Cc: Hugh Dickins <hughd@google.com> > > It's a pity about the unconditional pageblock lookup in that path but I > didn't see a better way around it so > > Acked-by: Mel Gorman <mgorman@suse.de>
Thanks but does that mean that v3 should be abandoned:
https://lkml.org/lkml/2014/3/6/365
?
Best regards, -- Bartlomiej Zolnierkiewicz Samsung R&D Institute Poland Samsung Electronics
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