On Mon, 17 Oct 2011, Joe Thornber wrote: > On Fri, Oct 14, 2011 at 03:14:34PM -0400, Mikulas Patocka wrote: > @@ -999,15 +1013,19 @@ again: > * someone is doing some writes simultaneously with us --- in > * this case, stop dropping the lock. > */ > if (dropped_lock) > goto again; > } > wake_up(&c->free_buffer_wait); > dm_bufio_unlock(c); > > - a = xchg(&c->async_write_error, 0); > + if (likely(!c->async_write_error)) > + a = 0; > + else > + a = xchg(&c->async_write_error, 0); > f = dm_bufio_issue_flush(c); > > > I didn't change this. Is it also fixing a preexisting issue? It doesn't fix anything. It just bypasses xchg for the most common case. Mikulas -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
