Messages in this thread | | | Date | Fri, 07 Sep 2012 09:48:51 +0900 | From | Kamezawa Hiroyuki <> | Subject | Re: [PATCH v3 4/4] memory-hotplug: fix pages missed by race rather than failng |
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(2012/09/07 9:39), Minchan Kim wrote: > If race between allocation and isolation in memory-hotplug offline > happens, some pages could be in MIGRATE_MOVABLE of free_list although > the pageblock's migratetype of the page is MIGRATE_ISOLATE. > > The race could be detected by get_freepage_migratetype > in __test_page_isolated_in_pageblock. If it is detected, now EBUSY > gets bubbled all the way up and the hotplug operations fails. > > But better idea is instead of returning and failing memory-hotremove, > move the free page to the correct list at the time it is detected. > It could enhance memory-hotremove operation success ratio although > the race is really rare. > > Suggested-by: Mel Gorman <mgorman@suse.de> > Signed-off-by: Minchan Kim <minchan@kernel.org>
Sounds reasonable. Thank you very much !
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
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