From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.netapp.com ([216.240.18.37]:7046 "EHLO mx2.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752673Ab1IWBVQ convert rfc822-to-8bit (ORCPT ); Thu, 22 Sep 2011 21:21:16 -0400 Subject: Re: [PATCH] VFS: Suppress automount on [l]stat, [l]getxattr, etc. From: Trond Myklebust To: Linus Torvalds Cc: Jeff Layton , Ian Kent , David Howells , miklos@szeredi.hu, viro@zeniv.linux.org.uk, gregkh@suse.de, linux-nfs@vger.kernel.org, leonardo.lists@gmail.com Date: Thu, 22 Sep 2011 21:21:13 -0400 In-Reply-To: References: <20110922134510.24683.14576.stgit@warthog.procyon.org.uk> <1316707443.3346.44.camel@perseus.themaw.net> <1316709935.3346.48.camel@perseus.themaw.net> <20110922133529.6d3ea8de@barsoom.rdu.redhat.com> <20110922144453.6cf53a25@barsoom.rdu.redhat.com> <1316719228.3968.14.camel@lade.trondhjem.org> <2E1EB2CF9ED1CB4AA966F0EB76EAB4430B480BD4@SACMVEXC2-PRD.hq.netapp.com> Content-Type: text/plain; charset="UTF-8" Message-ID: <1316740873.9186.19.camel@lade.trondhjem.org> Sender: linux-nfs-owner@vger.kernel.org List-ID: MIME-Version: 1.0 On Thu, 2011-09-22 at 18:04 -0700, Linus Torvalds wrote: > On Thu, Sep 22, 2011 at 5:56 PM, Myklebust, Trond > wrote: > > > > Your assumption is that in the majority of cases, we do _not_ want to > > automount the final directory unless we know that we are expecting a > > directory. > > Umm. That is the assumption yes, BUT THAT IS ALSO THE CURRENT STATE. > > So it's more than an assumption. It's a fact. > > So when you call it "assumption", you are basically ignoring and > trying to belittle current reality. Why? AFAICR, the whole point of doing the ->automount() stuff was to fix what was perceived to be a broken situation in which the application was more often than not seeing the properties of a directory which it would _never_ directly access. David, Ian, Al and I carefully listed the cases where we might want to optimise away the automount, and designed a system that fit those cases. I fully accept that we need to address any regressions that may have introduced, but your fix goes beyond the regressions that were reported: it basically puts us back where we were before the automount changes. In that situation, what have we gained by the changes, and why keep them at all? -- Trond Myklebust Linux NFS client maintainer NetApp Trond.Myklebust@netapp.com www.netapp.com