On Thu, Oct 31, 2013 at 09:50:17AM +0100, Michal Hocko wrote: > On Wed 30-10-13 15:12:48, Andrew Morton wrote: > > Subject: + mm-memcg-lockdep-annotation-for-memcg-oom-lock.patch added to -mm tree > > To: hannes@xxxxxxxxxxx,mhocko@xxxxxxx > > From: akpm@xxxxxxxxxxxxxxxxxxxx > > Date: Wed, 30 Oct 2013 15:12:48 -0700 > > > > > > The patch titled > > Subject: mm: memcg: lockdep annotation for memcg OOM lock > > has been added to the -mm tree. Its filename is > > mm-memcg-lockdep-annotation-for-memcg-oom-lock.patch > > > > This patch should soon appear at > > http://ozlabs.org/~akpm/mmots/broken-out/mm-memcg-lockdep-annotation-for-memcg-oom-lock.patch > > and later at > > http://ozlabs.org/~akpm/mmotm/broken-out/mm-memcg-lockdep-annotation-for-memcg-oom-lock.patch > > > > Before you just go and hit "reply", please: > > a) Consider who else should be cc'ed > > b) Prefer to cc a suitable mailing list as well > > c) Ideally: find the original patch on the mailing list and do a > > reply-to-all to that, adding suitable additional cc's > > > > *** Remember to use Documentation/SubmitChecklist when testing your code *** > > > > The -mm tree is included into linux-next and is updated > > there every 3-4 working days > > > > ------------------------------------------------------ > > From: Johannes Weiner <hannes@xxxxxxxxxxx> > > Subject: mm: memcg: lockdep annotation for memcg OOM lock > > > > The memcg OOM lock is a mutex-type lock that is open-coded due to memcg's > > special needs. Add annotations for lockdep coverage. > > I am not sure what this gives us to be honest. AA and AB-BA deadlocks > are impossible due to nature of the lock (it is trylock so we never > block on it). It's not an actual trylock, because we loop around it. If it fails, we wait for the unlock, restart the fault, and try again. That's a LOCK operation. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
