From patchwork Wed Mar 5 03:00:28 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: NeilBrown X-Patchwork-Id: 3770041 Return-Path: X-Original-To: patchwork-linux-nfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id E0AE5BF13A for ; Wed, 5 Mar 2014 03:01:18 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1BDA82022F for ; Wed, 5 Mar 2014 03:01:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DBC2520225 for ; Wed, 5 Mar 2014 03:01:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755512AbaCEDBQ (ORCPT ); Tue, 4 Mar 2014 22:01:16 -0500 Received: from cantor2.suse.de ([195.135.220.15]:52090 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755165AbaCEDBP (ORCPT ); Tue, 4 Mar 2014 22:01:15 -0500 Received: from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id D9787ACC3; Wed, 5 Mar 2014 03:01:14 +0000 (UTC) From: NeilBrown To: Trond Myklebust Date: Wed, 05 Mar 2014 14:00:28 +1100 Subject: [PATCH 1/8] NFS: nfs4_lookup_revalidate: only evaluate parent if it will be used. Cc: linux-nfs@vger.kernel.org Message-ID: <20140305030028.27421.54675.stgit@notabene.brown> In-Reply-To: <20140305025813.27421.23871.stgit@notabene.brown> References: <20140305025813.27421.23871.stgit@notabene.brown> User-Agent: StGit/0.16 MIME-Version: 1.0 Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP nfs4_lookup_revalidate only uses 'parent' to get 'dir', and only uses 'dir' if 'inode == NULL'. So we don't need to find out what 'parent' or 'dir' is until we know that 'inode' is NULL. By moving 'dget_parent' inside the 'if', we can reduce the number of call sites for 'dput(parent)'. Signed-off-by: NeilBrown --- fs/nfs/dir.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index be38b573495a..f5509f95f261 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -1496,9 +1496,7 @@ EXPORT_SYMBOL_GPL(nfs_atomic_open); static int nfs4_lookup_revalidate(struct dentry *dentry, unsigned int flags) { - struct dentry *parent = NULL; struct inode *inode; - struct inode *dir; int ret = 0; if (flags & LOOKUP_RCU) @@ -1512,34 +1510,35 @@ static int nfs4_lookup_revalidate(struct dentry *dentry, unsigned int flags) goto no_open; inode = dentry->d_inode; - parent = dget_parent(dentry); - dir = parent->d_inode; /* We can't create new files in nfs_open_revalidate(), so we * optimize away revalidation of negative dentries. */ if (inode == NULL) { + struct dentry *parent; + struct inode *dir; + + parent = dget_parent(dentry); + dir = parent->d_inode; if (!nfs_neg_need_reval(dir, dentry, flags)) ret = 1; + dput(parent); goto out; } /* NFS only supports OPEN on regular files */ if (!S_ISREG(inode->i_mode)) - goto no_open_dput; + goto no_open; /* We cannot do exclusive creation on a positive dentry */ if (flags & LOOKUP_EXCL) - goto no_open_dput; + goto no_open; /* Let f_op->open() actually open (and revalidate) the file */ ret = 1; out: - dput(parent); return ret; -no_open_dput: - dput(parent); no_open: return nfs_lookup_revalidate(dentry, flags); }