On Wed, Aug 25, 2010 at 12:43:40AM +0900, Minchan Kim wrote: > Now update_nr_listpages doesn't have a role. That's because > lists passed is always empty just after calling migrate_pages. > The migrate_pages cleans up page list which have failed to migrate > before returning by aaa994b3. > > [PATCH] page migration: handle freeing of pages in migrate_pages() > > Do not leave pages on the lists passed to migrate_pages(). Seems that we will > not need any postprocessing of pages. This will simplify the handling of > pages by the callers of migrate_pages(). > > At that time, we thought we don't need any postprocessing of pages. > But the situation is changed. The compaction need to know the number of > failed to migrate for COMPACTPAGEFAILED stat > > This patch makes new rule for caller of migrate_pages to call putback_lru_pages. > So caller need to clean up the lists so it has a chance to postprocess the pages. > [suggested by Christoph Lameter] > > Cc: Hugh Dickins <hughd@xxxxxxxxxx> > Cc: Andi Kleen <andi@xxxxxxxxxxxxxx> > Cc: Christoph Lameter <cl@xxxxxxxxx> > Cc: Mel Gorman <mel@xxxxxxxxx> > Signed-off-by: Minchan Kim <minchan.kim@xxxxxxxxx> Looks good and it passed basic testing. Reviewed-by: Mel Gorman <mel@xxxxxxxxx> Thanks -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>