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=-17.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,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 26AC7C433E9 for ; Fri, 29 Jan 2021 19:27:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D50E664DFB for ; Fri, 29 Jan 2021 19:27:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233009AbhA2T1S (ORCPT ); Fri, 29 Jan 2021 14:27:18 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48276 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232855AbhA2T1R (ORCPT ); Fri, 29 Jan 2021 14:27:17 -0500 Received: from fieldses.org (fieldses.org [IPv6:2600:3c00:e000:2f7::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 07F07C061574; Fri, 29 Jan 2021 11:27:02 -0800 (PST) Received: by fieldses.org (Postfix, from userid 2815) id 7A2254163; Fri, 29 Jan 2021 14:27:01 -0500 (EST) DKIM-Filter: OpenDKIM Filter v2.11.0 fieldses.org 7A2254163 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fieldses.org; s=default; t=1611948421; bh=Czt3r+DII0qD79e+XDEsUiPQlCPOuV8iSW4i1vozb+8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=cMQpszRGMhwbbGuK/BZ9DB3fryZxvUhKKBw3H85anxYNPA8OVrSPULJsKsHwHgFYh anIOtEZeNVlWSQ9PVxujP+gOSotRy2Ind+fOTw08so9petmb704BQsF2/zE8Pnt1fZ YmbpBpsLyoq9E3zx3CStYrN6jWfnAD+woZJs17yg= Date: Fri, 29 Jan 2021 14:27:01 -0500 From: "J. Bruce Fields" To: Christoph Hellwig Cc: "J. Bruce Fields" , linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, Trond Myklebust , Anna Schumaker , Chuck Lever Subject: [PATCH 2/2 v2] nfsd: skip some unnecessary stats in the v4 case Message-ID: <20210129192701.GD8033@fieldses.org> References: <1611084297-27352-1-git-send-email-bfields@redhat.com> <1611084297-27352-3-git-send-email-bfields@redhat.com> <20210120084638.GA3678536@infradead.org> <20210121202756.GA13298@pick.fieldses.org> <20210122082059.GA119852@infradead.org> <20210129192629.GC8033@fieldses.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210129192629.GC8033@fieldses.org> User-Agent: Mutt/1.5.21 (2010-09-15) Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org From: "J. Bruce Fields" In the typical case of v4 and an i_version-supporting filesystem, we can skip a stat which is only required to fake up a change attribute from ctime. Signed-off-by: J. Bruce Fields --- fs/nfsd/nfs3xdr.c | 42 +++++++++++++++++++++++++----------------- 1 file changed, 25 insertions(+), 17 deletions(-) diff --git a/fs/nfsd/nfs3xdr.c b/fs/nfsd/nfs3xdr.c index 821db21ba072..8bcda5274089 100644 --- a/fs/nfsd/nfs3xdr.c +++ b/fs/nfsd/nfs3xdr.c @@ -252,6 +252,11 @@ encode_wcc_data(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp) return encode_post_op_attr(rqstp, p, fhp); } +static bool fs_supports_change_attribute(struct super_block *sb) +{ + return sb->s_flags & SB_I_VERSION || sb->s_export_op->fetch_iversion; +} + /* * Fill in the pre_op attr for the wcc data */ @@ -260,24 +265,25 @@ void fill_pre_wcc(struct svc_fh *fhp) struct inode *inode; struct kstat stat; bool v4 = (fhp->fh_maxsize == NFS4_FHSIZE); - __be32 err; if (fhp->fh_no_wcc || fhp->fh_pre_saved) return; inode = d_inode(fhp->fh_dentry); - err = fh_getattr(fhp, &stat); - if (err) { - /* Grab the times from inode anyway */ - stat.mtime = inode->i_mtime; - stat.ctime = inode->i_ctime; - stat.size = inode->i_size; + if (fs_supports_change_attribute(inode->i_sb) || !v4) { + __be32 err = fh_getattr(fhp, &stat); + if (err) { + /* Grab the times from inode anyway */ + stat.mtime = inode->i_mtime; + stat.ctime = inode->i_ctime; + stat.size = inode->i_size; + } + fhp->fh_pre_mtime = stat.mtime; + fhp->fh_pre_ctime = stat.ctime; + fhp->fh_pre_size = stat.size; } if (v4) fhp->fh_pre_change = nfsd4_change_attribute(&stat, inode); - fhp->fh_pre_mtime = stat.mtime; - fhp->fh_pre_ctime = stat.ctime; - fhp->fh_pre_size = stat.size; fhp->fh_pre_saved = true; } @@ -288,7 +294,6 @@ void fill_post_wcc(struct svc_fh *fhp) { bool v4 = (fhp->fh_maxsize == NFS4_FHSIZE); struct inode *inode = d_inode(fhp->fh_dentry); - __be32 err; if (fhp->fh_no_wcc) return; @@ -296,12 +301,15 @@ void fill_post_wcc(struct svc_fh *fhp) if (fhp->fh_post_saved) printk("nfsd: inode locked twice during operation.\n"); - err = fh_getattr(fhp, &fhp->fh_post_attr); - if (err) { - fhp->fh_post_saved = false; - fhp->fh_post_attr.ctime = inode->i_ctime; - } else - fhp->fh_post_saved = true; + fhp->fh_post_saved = true; + + if (fs_supports_change_attribute(inode->i_sb) || !v4) { + __be32 err = fh_getattr(fhp, &fhp->fh_post_attr); + if (err) { + fhp->fh_post_saved = false; + fhp->fh_post_attr.ctime = inode->i_ctime; + } + } if (v4) fhp->fh_post_change = nfsd4_change_attribute(&fhp->fh_post_attr, inode); -- 2.29.2