mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Trond Myklebust <Trond.Myklebust@netapp.com>
To: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Wolfgang Walter <wolfgang.walter@stwm.de>,
	linux-kernel@vger.kernel.org, linux-nfs@vger.kernel.org
Subject: Re: problem with nfs4: rpciod seems to loop in rpc_shutdown_client forever
Date: Mon, 21 Mar 2011 19:35:36 -0400	[thread overview]
Message-ID: <1300750536.26546.31.camel@lade.trondhjem.org> (raw)
In-Reply-To: <20110321232857.GC472@fieldses.org>

On Mon, 2011-03-21 at 19:28 -0400, J. Bruce Fields wrote:
> On Fri, Mar 18, 2011 at 11:49:21PM +0100, Wolfgang Walter wrote:
> > Hello,
> > 
> > I have a problem with our nfs-server (stable 2.6.32.33 but also with
> > .31 or .32 and probably older ones): sometimes
> > one or more rpciod get stuck. I used
> > 
> > 	rpcdebug -m rpc -s all
> > 
> > I get messages as the following one about every second:
> > 
> > Mar 18 11:15:37 au kernel: [44640.906793] RPC:       killing all tasks for client ffff88041c51de00
> > Mar 18 11:15:38 au kernel: [44641.906793] RPC:       killing all tasks for client ffff88041c51de00
> > Mar 18 11:15:39 au kernel: [44642.906795] RPC:       killing all tasks for client ffff88041c51de00
> > Mar 18 11:15:40 au kernel: [44643.906793] RPC:       killing all tasks for client ffff88041c51de00
> > Mar 18 11:15:41 au kernel: [44644.906795] RPC:       killing all tasks for client ffff88041c51de00
> > Mar 18 11:15:42 au kernel: [44645.906794] RPC:       killing all tasks for client ffff88041c51de00
> > 
> > and I get this messages:
> > 
> > Mar 18 22:45:57 au kernel: [86061.779008]   174 0381     -5 ffff88041c51de00   (null)        0 ffffffff817211a0 nfs4_cbv1 CB_NULL a:rpc_exit_task q:none
> > 
> > My theorie is this one:
> > 
> > * this async task is runnable but does not progress (calling rpc_exit_task).
> > * this is because the same rpciod which handles this task loops in
> >   rpc_shutdown_client waiting for this task to go away.
> > * because rpc_shutdown_client is called from an async rpc, too
> 
> Off hand I don't see any place where rpc_shutdown_client() is called
> from rpciod; do you?

The only case I could think of would be if we're still calling mntput()
from some RPC callback. In principle we should only be doing that from
the rpc_call_ops->rpc_callback() from within the nfsiod thread rather
than rpciod.

Is it possible this might be another instance of the nfs_commit_inode()
busy-loop?

-- 
Trond Myklebust
Linux NFS client maintainer

NetApp
Trond.Myklebust@netapp.com
www.netapp.com


  reply	other threads:[~2011-03-21 23:35 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-03-18 22:49 Wolfgang Walter
2011-03-21 23:28 ` J. Bruce Fields
2011-03-21 23:35   ` Trond Myklebust [this message]
2011-03-22 14:52   ` Wolfgang Walter
2011-03-22 15:01     ` J. Bruce Fields
2011-03-23  7:54       ` Wolfgang Walter

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1300750536.26546.31.camel@lade.trondhjem.org \
    --to=trond.myklebust@netapp.com \
    --cc=bfields@fieldses.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-nfs@vger.kernel.org \
    --cc=wolfgang.walter@stwm.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®