On Tue, 17 Aug 2010, Andi Kleen wrote: > On Tue, Aug 17, 2010 at 09:46:56AM -0400, Jeff Moyer wrote: > > Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> writes: > > > > > BTW, from the discussion with Christoph I noticed my misunderstanding > > > about the necessity of additional page locking. It would seem that > > > without page locking there is no danger of racing between direct I/O and > > > page migration. So I retract this additional locking patch-set. > > > > OK, great! ;-) > > Well it sounds like we still may need something. It isn't good if O_DIRECT > can starve (or DoS) migration. Anything that increments a page refcount can interfere with migration and cause migration to be aborted and retried later. Not something new. There never was any guarantee that migration must succeed. -- 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>