On Tue, 6 Oct 2015, Mike Snitzer wrote: > On Tue, Oct 06 2015 at 9:28am -0400, > Mikulas Patocka <mpatocka@xxxxxxxxxx> wrote: > > > > > > > On Mon, 5 Oct 2015, Mike Snitzer wrote: > > > > > Mikulas, > > > > > > Could it be that cond_resched() wasn't unplugging? As was > > > recently raised in this thread: https://lkml.org/lkml/2015/9/18/378 > > > Chris Mason's patch from that thread fixed this issue... I _think_ Linus > > > has since committed Chris' work but I haven't kept my finger on the > > > pulse of that issue. > > > > I think it doesn't matter (regarding correctness) if cond_reched unplugs > > on not. If it didn't unplug, the process will be scheduled later, and it > > will eventually reach the point where it unplugs. > > Couldn't the original deadlock you fixed (as described in your first > patch) manifest when a new process is scheduled? A process rescheduled with cond_reched is not stuck, it will be run later. It may contribute to increased request latency, but it can't contribute to a deadlock. Mikulas -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
