From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754042AbcCAXuw (ORCPT ); Tue, 1 Mar 2016 18:50:52 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:45947 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753419AbcCAXr3 (ORCPT ); Tue, 1 Mar 2016 18:47:29 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Al Viro Subject: [PATCH 3.14 026/130] split dentry_kill() Date: Tue, 1 Mar 2016 15:44:37 -0800 Message-Id: <20160301234500.688361018@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 3.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Al Viro commit e55fd011549eae01a230e3cace6f4d031b6a3453 upstream. ... into trylocks and everything else. The latter (actual killing) is __dentry_kill(). Signed-off-by: Al Viro Signed-off-by: Greg Kroah-Hartman --- fs/dcache.c | 62 ++++++++++++++++++++++++++++++++++-------------------------- 1 file changed, 36 insertions(+), 26 deletions(-) --- a/fs/dcache.c +++ b/fs/dcache.c @@ -439,36 +439,12 @@ void d_drop(struct dentry *dentry) } EXPORT_SYMBOL(d_drop); -/* - * Finish off a dentry we've decided to kill. - * dentry->d_lock must be held, returns with it unlocked. - * If ref is non-zero, then decrement the refcount too. - * Returns dentry requiring refcount drop, or NULL if we're done. - */ -static struct dentry * -dentry_kill(struct dentry *dentry, int unlock_on_failure) - __releases(dentry->d_lock) +static void __dentry_kill(struct dentry *dentry) { - struct inode *inode; struct dentry *parent = NULL; bool can_free = true; - - inode = dentry->d_inode; - if (inode && !spin_trylock(&inode->i_lock)) { -relock: - if (unlock_on_failure) { - spin_unlock(&dentry->d_lock); - cpu_relax(); - } - return dentry; /* try again with same dentry */ - } if (!IS_ROOT(dentry)) parent = dentry->d_parent; - if (parent && !spin_trylock(&parent->d_lock)) { - if (inode) - spin_unlock(&inode->i_lock); - goto relock; - } /* * The dentry is now unrecoverably dead to the world. @@ -512,10 +488,44 @@ relock: can_free = false; } spin_unlock(&dentry->d_lock); -out: if (likely(can_free)) dentry_free(dentry); +} + +/* + * Finish off a dentry we've decided to kill. + * dentry->d_lock must be held, returns with it unlocked. + * If ref is non-zero, then decrement the refcount too. + * Returns dentry requiring refcount drop, or NULL if we're done. + */ +static struct dentry * +dentry_kill(struct dentry *dentry, int unlock_on_failure) + __releases(dentry->d_lock) +{ + struct inode *inode = dentry->d_inode; + struct dentry *parent = NULL; + + if (inode && unlikely(!spin_trylock(&inode->i_lock))) + goto failed; + + if (!IS_ROOT(dentry)) { + parent = dentry->d_parent; + if (unlikely(!spin_trylock(&parent->d_lock))) { + if (inode) + spin_unlock(&inode->i_lock); + goto failed; + } + } + + __dentry_kill(dentry); return parent; + +failed: + if (unlock_on_failure) { + spin_unlock(&dentry->d_lock); + cpu_relax(); + } + return dentry; /* try again with same dentry */ } /*