On Thu, Apr 03, 2014 at 05:40:18PM +0200, Vlastimil Babka wrote: > For the MIGRATE_RESERVE pages, it is important they do not get misplaced > on free_list of other migratetype, otherwise the whole MIGRATE_RESERVE > pageblock might be changed to other migratetype in try_to_steal_freepages(). > For MIGRATE_CMA, the pages also must not go to a different free_list, > otherwise > they could get allocated as unmovable and result in CMA failure. > > This is ensured by setting the freepage_migratetype appropriately when placing > pages on pcp lists, and using the information when releasing them back to > free_list. It is also assumed that CMA and RESERVE pageblocks are created only > in the init phase. This patch adds DEBUG_VM checks to catch any regressions > introduced for this invariant.
Hello, Vlastimil. Idea looks good to me. > > Cc: Yong-Taek Lee <[email protected]> > Cc: Bartlomiej Zolnierkiewicz <[email protected]> > Cc: Joonsoo Kim <[email protected]> > Cc: Mel Gorman <[email protected]> > Cc: Minchan Kim <[email protected]> > Cc: KOSAKI Motohiro <[email protected]> > Cc: Marek Szyprowski <[email protected]> > Cc: Hugh Dickins <[email protected]> > Cc: Rik van Riel <[email protected]> > Cc: Michal Nazarewicz <[email protected]> > Signed-off-by: Vlastimil Babka <[email protected]> Acked-by: Joonsoo Kim <[email protected]> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
