From patchwork Mon Feb 21 16:08:45 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Trond Myklebust X-Patchwork-Id: 12753862 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EA27BC433F5 for ; Mon, 21 Feb 2022 16:16:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1379991AbiBUQP2 (ORCPT ); Mon, 21 Feb 2022 11:15:28 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:40060 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1379986AbiBUQPZ (ORCPT ); Mon, 21 Feb 2022 11:15:25 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D8F5027B09 for ; Mon, 21 Feb 2022 08:15:02 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 7064D612A3 for ; Mon, 21 Feb 2022 16:15:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 18203C340F1 for ; Mon, 21 Feb 2022 16:15:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1645460102; bh=KmywsLUD8y02FPy3fCK28yoWL5oPPleON/q3PmiX2QY=; h=From:To:Subject:Date:In-Reply-To:References:From; b=C0cw1GpTo2ZOa8TIvI9vGhgXLMXRtfKJRwQLT+pnbF+L0om6U3xcxWNk+Kc3kcIVx H5EDXZDhRUNk8bNHob1MF3RHaWTz1KWvOdoEi70Vql12t2BxGF5NIeLp5faxe2SNwB +JyWK17E6nVXxllWSsEcDZNnqGeTa5YCYwrkizj4h3H1J39Xj5JyTa1gFMy/o9d6G9 9ys6DWt02rA3B2IztL1vDrFmfAspa+u0Lm45U3Y0mRwjaxGAurh046hfXAtfG+EZRU sqdMcptzf7yKFXBa8GFSp7sDUxuKEh3GNG0eOsERqzirb6po2gRxdUuNbFzTWcoeG3 nU4FTC4Kk2L4Q== From: trondmy@kernel.org To: linux-nfs@vger.kernel.org Subject: [PATCH v6 07/13] NFS: Don't ask for readdirplus unless it can help nfs_getattr() Date: Mon, 21 Feb 2022 11:08:45 -0500 Message-Id: <20220221160851.15508-8-trondmy@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220221160851.15508-7-trondmy@kernel.org> References: <20220221160851.15508-1-trondmy@kernel.org> <20220221160851.15508-2-trondmy@kernel.org> <20220221160851.15508-3-trondmy@kernel.org> <20220221160851.15508-4-trondmy@kernel.org> <20220221160851.15508-5-trondmy@kernel.org> <20220221160851.15508-6-trondmy@kernel.org> <20220221160851.15508-7-trondmy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org From: Trond Myklebust If attribute caching is turned off, then use of readdirplus is not going to help stat() performance. Readdirplus also doesn't help if a file is being written to, since we will have to flush those writes in order to sync the mtime/ctime. Signed-off-by: Trond Myklebust --- fs/nfs/inode.c | 33 +++++++++++++++++---------------- 1 file changed, 17 insertions(+), 16 deletions(-) diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index 1bef81f5373a..9d2af9887715 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -782,24 +782,26 @@ void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr, } EXPORT_SYMBOL_GPL(nfs_setattr_update_inode); -static void nfs_readdirplus_parent_cache_miss(struct dentry *dentry) +/* + * Don't request help from readdirplus if the file is being written to, + * or if attribute caching is turned off + */ +static bool nfs_getattr_readdirplus_enable(const struct inode *inode) { - struct dentry *parent; + return nfs_server_capable(inode, NFS_CAP_READDIRPLUS) && + !nfs_have_writebacks(inode) && NFS_MAXATTRTIMEO(inode) > 5 * HZ; +} - if (!nfs_server_capable(d_inode(dentry), NFS_CAP_READDIRPLUS)) - return; - parent = dget_parent(dentry); +static void nfs_readdirplus_parent_cache_miss(struct dentry *dentry) +{ + struct dentry *parent = dget_parent(dentry); nfs_readdir_record_entry_cache_miss(d_inode(parent)); dput(parent); } static void nfs_readdirplus_parent_cache_hit(struct dentry *dentry) { - struct dentry *parent; - - if (!nfs_server_capable(d_inode(dentry), NFS_CAP_READDIRPLUS)) - return; - parent = dget_parent(dentry); + struct dentry *parent = dget_parent(dentry); nfs_readdir_record_entry_cache_hit(d_inode(parent)); dput(parent); } @@ -837,6 +839,7 @@ int nfs_getattr(struct user_namespace *mnt_userns, const struct path *path, int err = 0; bool force_sync = query_flags & AT_STATX_FORCE_SYNC; bool do_update = false; + bool readdirplus_enabled = nfs_getattr_readdirplus_enable(inode); trace_nfs_getattr_enter(inode); @@ -845,7 +848,8 @@ int nfs_getattr(struct user_namespace *mnt_userns, const struct path *path, STATX_INO | STATX_SIZE | STATX_BLOCKS; if ((query_flags & AT_STATX_DONT_SYNC) && !force_sync) { - nfs_readdirplus_parent_cache_hit(path->dentry); + if (readdirplus_enabled) + nfs_readdirplus_parent_cache_hit(path->dentry); goto out_no_revalidate; } @@ -895,15 +899,12 @@ int nfs_getattr(struct user_namespace *mnt_userns, const struct path *path, do_update |= cache_validity & NFS_INO_INVALID_BLOCKS; if (do_update) { - /* Update the attribute cache */ - if (!(server->flags & NFS_MOUNT_NOAC)) + if (readdirplus_enabled) nfs_readdirplus_parent_cache_miss(path->dentry); - else - nfs_readdirplus_parent_cache_hit(path->dentry); err = __nfs_revalidate_inode(server, inode); if (err) goto out; - } else + } else if (readdirplus_enabled) nfs_readdirplus_parent_cache_hit(path->dentry); out_no_revalidate: /* Only return attributes that were revalidated. */