Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-qc0-f172.google.com ([209.85.216.172]:64156 "EHLO mail-qc0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752374AbaGJMnD (ORCPT ); Thu, 10 Jul 2014 08:43:03 -0400 Received: by mail-qc0-f172.google.com with SMTP id l6so667340qcy.3 for ; Thu, 10 Jul 2014 05:43:02 -0700 (PDT) From: Jeff Layton Date: Thu, 10 Jul 2014 08:43:00 -0400 To: Christoph Hellwig Cc: bfields@fieldses.org, linux-nfs@vger.kernel.org Subject: Re: [PATCH v4 003/100] nfsd: Ensure stateids remain unique until they are freed Message-ID: <20140710084300.3ef4d466@tlielax.poochiereds.net> In-Reply-To: <20140710112342.GB10893@infradead.org> References: <1404842668-22521-1-git-send-email-jlayton@primarydata.com> <1404842668-22521-4-git-send-email-jlayton@primarydata.com> <20140710112342.GB10893@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-nfs-owner@vger.kernel.org List-ID: On Thu, 10 Jul 2014 04:23:42 -0700 Christoph Hellwig wrote: > On Tue, Jul 08, 2014 at 02:02:51PM -0400, Jeff Layton wrote: > > From: Trond Myklebust > > > > Add an extra delegation state to allow the stateid to remain in the idr > > tree until the last reference has been released. This will be necessary > > to ensure uniqueness once the client_mutex is removed. > > > > [jlayton: reset the sc_type under the state_lock in unhash_delegation] > > I'd be tempted to instead have a closed flag, there's plenty of space in > the hole after sc_type anyway. > > The rationale for that is that a stateid really shouldn't change the > type during it's life time, and callers that specify the type to look > up shouldn't bother with looking up different types due to this either. > > NFS4_REVOKED_DELEG_STID would also be replaced by a revoked flag, which > makes much more sene to start with as well. > That sort of change will ripple throughout the set. Your point about not changing the sc_type is valid though. I'll see whether it's doable. > Btw, do you also plan to keep open stateids as NFS4_CLOSED_STID for > 4.1+? In that case the comment there would need an update. What about > lock stateids? > No. For v4.1+ we have no need to keep stateids around that are closed. They are released as soon as the close occurs. The only reason to keep them around is for v4.0 replays. -- Jeff Layton