Messages in this thread | | | From | "Myklebust, Trond" <> | Subject | Re: nfsd oops on Linus' current tree. | Date | Thu, 3 Jan 2013 22:12:32 +0000 |
| |
On Thu, 2013-01-03 at 17:08 -0500, Tejun Heo wrote: > Hello, > > On Thu, Jan 03, 2013 at 03:11:20PM -0500, J. Bruce Fields wrote: > > Both rpciod and nfsiod already set WQ_MEM_RECLAIM. > > > > But, right, looking at kernel/workqueue.c, it seems that the dedicated > > "rescuer" threads are invoked only in the case when work is stalled > > because a new worker thread isn't allocated quickly enough. > > Because that's the *only* case where progress can't be guaranteed > otherwise. > > > So, what to do that's simplest enough that it would work for > > post-rc2/stable? I was happy having just a simple dedicated > > thread--these are only started when nfsd is, so there's no real thread > > proliferation problem. > > The analysis is likely completely wrong, so please don't go off doing > something unnecessary. Please take look at what's causing the > deadlocks again.
The analysis is a no-brainer: We see a deadlock due to one work item waiting for completion of another work item that is queued on the same CPU. There is no other dependency between the two work items.
-- Trond Myklebust Linux NFS client maintainer
NetApp Trond.Myklebust@netapp.com www.netapp.com
| |