Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753995AbcCAXuh (ORCPT ); Tue, 1 Mar 2016 18:50:37 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:46137 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753455AbcCAXra (ORCPT ); Tue, 1 Mar 2016 18:47:30 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Al Viro Subject: [PATCH 3.14 027/130] expand dentry_kill(dentry, 0) in shrink_dentry_list() Date: Tue, 1 Mar 2016 15:44:38 -0800 Message-Id: <20160301234500.719349323@linuxfoundation.org> X-Mailer: git-send-email 2.7.2 In-Reply-To: <20160301234459.768886030@linuxfoundation.org> References: <20160301234459.768886030@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1968 Lines: 71 3.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Al Viro commit ff2fde9929feb2aef45377ce56b8b12df85dda69 upstream. Result will be massaged to saner shape in the next commits. It is ugly, no questions - the point of that one is to be a provably equivalent transformation (and it might be worth splitting a bit more). Signed-off-by: Al Viro Signed-off-by: Greg Kroah-Hartman --- fs/dcache.c | 30 +++++++++++++++++------------- 1 file changed, 17 insertions(+), 13 deletions(-) --- a/fs/dcache.c +++ b/fs/dcache.c @@ -802,6 +802,7 @@ static void shrink_dentry_list(struct li struct dentry *dentry, *parent; while (!list_empty(list)) { + struct inode *inode; dentry = list_entry(list->prev, struct dentry, d_lru); spin_lock(&dentry->d_lock); /* @@ -829,23 +830,26 @@ static void shrink_dentry_list(struct li continue; } - parent = dentry_kill(dentry, 0); - /* - * If dentry_kill returns NULL, we have nothing more to do. - */ - if (!parent) - continue; - - if (unlikely(parent == dentry)) { - /* - * trylocks have failed and d_lock has been held the - * whole time, so it could not have been added to any - * other lists. Just add it back to the shrink list. - */ + inode = dentry->d_inode; + if (inode && unlikely(!spin_trylock(&inode->i_lock))) { d_shrink_add(dentry, list); spin_unlock(&dentry->d_lock); continue; } + + parent = NULL; + if (!IS_ROOT(dentry)) { + parent = dentry->d_parent; + if (unlikely(!spin_trylock(&parent->d_lock))) { + if (inode) + spin_unlock(&inode->i_lock); + d_shrink_add(dentry, list); + spin_unlock(&dentry->d_lock); + continue; + } + } + + __dentry_kill(dentry); /* * We need to prune ancestors too. This is necessary to prevent * quadratic behavior of shrink_dcache_parent(), but is also