On Mon, Dec 12, 2011 at 03:35:03PM +0100, Michal Nazarewicz wrote: > >On Fri, Nov 18, 2011 at 05:43:10PM +0100, Marek Szyprowski wrote: > >>From: Michal Nazarewicz <mina86@xxxxxxxxxx> > >>diff --git a/mm/compaction.c b/mm/compaction.c > >>index 6afae0e..09c9702 100644 > >>--- a/mm/compaction.c > >>+++ b/mm/compaction.c > >>@@ -111,7 +111,10 @@ skip: > >> > >> next: > >> pfn += isolated; > >>- page += isolated; > >>+ if (zone_pfn_same_memmap(pfn - isolated, pfn)) > >>+ page += isolated; > >>+ else > >>+ page = pfn_to_page(pfn); > >> } > > On Mon, 12 Dec 2011 15:19:53 +0100, Mel Gorman <mel@xxxxxxxxx> wrote: > >Is this necessary? > > > >We are isolating pages, the largest of which is a MAX_ORDER_NR_PAGES > >page. [...] > > This is not true for CMA. > To be clear, I'm referring to a single page being isolated here. It may or may not be a high-order page but it's still going to be less then MAX_ORDER_NR_PAGES so you should be able check when a new block is entered and pfn_to_page is necessary. -- Mel Gorman SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>