From mboxrd@z Thu Jan 1 00:00:00 1970 From: Cong Wang Subject: [Patch 3.14 stable 09/16] lift the "already marked killed" case into shrink_dentry_list() Date: Thu, 6 Nov 2014 11:37:13 -0800 Message-ID: <1415302640-5876-10-git-send-email-xiyou.wangcong@gmail.com> References: <1415302640-5876-1-git-send-email-xiyou.wangcong@gmail.com> Cc: viro@zeniv.linux.org.uk, gregkh@linuxfoundation.org, linux-fsdevel@vger.kernel.org To: stable@vger.kernel.org Return-path: Received: from mail-pd0-f177.google.com ([209.85.192.177]:50850 "EHLO mail-pd0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751255AbaKFThx (ORCPT ); Thu, 6 Nov 2014 14:37:53 -0500 In-Reply-To: <1415302640-5876-1-git-send-email-xiyou.wangcong@gmail.com> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: From: Al Viro It can happen only when dentry_kill() is called with unlock_on_failure equal to 0 - other callers had dentry pinned until the moment they've got ->d_lock and DCACHE_DENTRY_KILLED is set only after lockref_mark_dead(). IOW, only one of three call sites of dentry_kill() might end up reaching that code. Just move it there. Signed-off-by: Al Viro (cherry picked from commit 64fd72e0a44bdd62c5ca277cb24d0d02b2d8e9dc) --- fs/dcache.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/fs/dcache.c b/fs/dcache.c index d20bae3..b2ad032 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -454,12 +454,6 @@ dentry_kill(struct dentry *dentry, int unlock_on_failure) struct dentry *parent = NULL; bool can_free = true; - if (unlikely(dentry->d_flags & DCACHE_DENTRY_KILLED)) { - can_free = dentry->d_flags & DCACHE_MAY_FREE; - spin_unlock(&dentry->d_lock); - goto out; - } - inode = dentry->d_inode; if (inode && !spin_trylock(&inode->i_lock)) { relock: @@ -814,6 +808,15 @@ static void shrink_dentry_list(struct list_head *list) continue; } + + if (unlikely(dentry->d_flags & DCACHE_DENTRY_KILLED)) { + bool can_free = dentry->d_flags & DCACHE_MAY_FREE; + spin_unlock(&dentry->d_lock); + if (can_free) + dentry_free(dentry); + continue; + } + parent = dentry_kill(dentry, 0); /* * If dentry_kill returns NULL, we have nothing more to do. -- 1.8.3.1