lkml.org 
[lkml]   [2013]   [Jan]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: nfsd oops on Linus' current tree.
Date
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


\
 
 \ /
  Last update: 2013-01-03 23:41    [W:0.096 / U:1.972 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site