On Tue, Aug 13, 2013 at 11:46:42AM +0200, Krzysztof Kozlowski wrote: > Hi Minchan, > > On wto, 2013-08-13 at 16:04 +0900, Minchan Kim wrote: > > patch 2 introduce pinpage control > > subsystem. So, subsystems want to control pinpage should implement own > > pinpage_xxx functions because each subsystem would have other character > > so what kinds of data structure for managing pinpage information depends > > on them. Otherwise, they can use general functions defined in pinpage > > subsystem. patch 3 hacks migration.c so that migration is > > aware of pinpage now and migrate them with pinpage subsystem. > > I wonder why don't we use page->mapping and a_ops? Is there any > disadvantage of such mapping/a_ops? That's what the pending aio patches do, and I think this is a better approach for those use-cases that the technique works for. The biggest problem I see with the pinpage approach is that it's based on a single page at a time. I'd venture a guess that many pinned pages are done in groups of pages, not single ones. -ben > Best regards, > Krzysztof -- "Thought is the essence of where you are now." -- 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/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>