From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 12819C47404 for ; Wed, 9 Oct 2019 19:51:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D70A020B7C for ; Wed, 9 Oct 2019 19:51:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730490AbfJITvW (ORCPT ); Wed, 9 Oct 2019 15:51:22 -0400 Received: from fieldses.org ([173.255.197.46]:48438 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728804AbfJITvW (ORCPT ); Wed, 9 Oct 2019 15:51:22 -0400 Received: by fieldses.org (Postfix, from userid 2815) id EBBE71C24; Wed, 9 Oct 2019 15:51:21 -0400 (EDT) Date: Wed, 9 Oct 2019 15:51:21 -0400 From: "J. Bruce Fields" To: Scott Mayhew Cc: chuck.lever@oracle.com, linux-nfs@vger.kernel.org Subject: Re: [PATCH] nfsd4: fix up replay_matches_cache() Message-ID: <20191009195121.GA23703@fieldses.org> References: <20191009191137.28007-1-smayhew@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191009191137.28007-1-smayhew@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org On Wed, Oct 09, 2019 at 03:11:37PM -0400, Scott Mayhew wrote: > When running an nfs stress test, I see quite a few cached replies that > don't match up with the actual request. The first comment in > replay_matches_cache() makes sense, but the code doesn't seem to > match... fix it. Thanks, I'll apply. But I'm curious whether you're seeing any practical impact from this? I don't think it should matter. --b. > > Fixes: 53da6a53e1d4 ("nfsd4: catch some false session retries") > Signed-off-by: Scott Mayhew > --- > fs/nfsd/nfs4state.c | 15 ++++++++++----- > 1 file changed, 10 insertions(+), 5 deletions(-) > > diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c > index c65aeaa812d4..08f6eb2b73f8 100644 > --- a/fs/nfsd/nfs4state.c > +++ b/fs/nfsd/nfs4state.c > @@ -3548,12 +3548,17 @@ static bool replay_matches_cache(struct svc_rqst *rqstp, > (bool)seq->cachethis) > return false; > /* > - * If there's an error than the reply can have fewer ops than > - * the call. But if we cached a reply with *more* ops than the > - * call you're sending us now, then this new call is clearly not > - * really a replay of the old one: > + * If there's an error then the reply can have fewer ops than > + * the call. > */ > - if (slot->sl_opcnt < argp->opcnt) > + if (slot->sl_opcnt < argp->opcnt && !slot->sl_status) > + return false; > + /* > + * But if we cached a reply with *more* ops than the call you're > + * sending us now, then this new call is clearly not really a > + * replay of the old one: > + */ > + if (slot->sl_opcnt > argp->opcnt) > return false; > /* This is the only check explicitly called by spec: */ > if (!same_creds(&rqstp->rq_cred, &slot->sl_cred)) > -- > 2.17.2