On Mon, Nov 04 2013 at 10:25am -0500, Mikulas Patocka <mpatocka@xxxxxxxxxx> wrote: > > > On Mon, 4 Nov 2013, Mike Snitzer wrote: > > > On Mon, Nov 04 2013 at 10:06am -0500, > > Mikulas Patocka <mpatocka@xxxxxxxxxx> wrote: > > > > > > The code uses atomic_inc for restoration of bi_remaining. This patch > > > changes it to atomic_set(1) to avoid an interlocked instruction. In the > > > target's bi_endio routine we are sure that bi_remaining is zero > > > (otherwise, the bi_endio routine wouldn't be called) and there are no > > > concurrent users of the bio, so we can replace atomic_inc with > > > atomic_set(1). > > > > This isn't DM-specific. Shouldn't the other places in the tree that use > > atomic_inc on bi_remaining should really be converted at the same time? > > There is no 'atomic_inc.*bi_remaining' in other drivers. Wrong. I know btrfs has at least one. As does bcache afaik. -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
