On Wed, Aug 30, 2017 at 12:51:09AM -0700, Christoph Hellwig wrote: > On Wed, Aug 30, 2017 at 05:29:50PM +1000, Dave Chinner wrote: > > Quick patch below, doesn't work on reflink filesystems yet because > > the way it handles cached COW mapping invalidation is unnecessarily > > special and so doesn't work. Can you test it and see if it fixes the > > problem? > > FYI, I thought about this problem a while ago in the context of > rcu lookups of the extent tree (not, I'm not doing those quite yet, > but I though of the possibilities once we've got a btree!) and > then my answer was that we'd really need a seqlock around uses of > the imaps. I didn't think far enough that we might need something > like that even now.. Now that you mention it, a seqlock is probably a pretty good fit for this. I'll have a look at it tomorrow.... Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
