From patchwork Fri Feb 24 13:14:45 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 9590285 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 7A56660471 for ; Fri, 24 Feb 2017 13:17:04 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4A5712866A for ; Fri, 24 Feb 2017 13:17:04 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3D8DD28756; Fri, 24 Feb 2017 13:17:04 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DA889286E0 for ; Fri, 24 Feb 2017 13:17:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751702AbdBXNQ6 (ORCPT ); Fri, 24 Feb 2017 08:16:58 -0500 Received: from mx1.redhat.com ([209.132.183.28]:59826 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751544AbdBXNOx (ORCPT ); Fri, 24 Feb 2017 08:14:53 -0500 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 9B47F635F2; Fri, 24 Feb 2017 13:14:48 +0000 (UTC) Received: from warthog.procyon.org.uk (ovpn-120-66.rdu2.redhat.com [10.10.120.66] (may be forged)) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id v1ODEkS3016316; Fri, 24 Feb 2017 08:14:47 -0500 Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH 11/14] afs: inode: Replace rcu_assign_pointer() with RCU_INIT_POINTER() From: David Howells To: viro@ZenIV.linux.org.uk Cc: dhowells@redhat.com, Andreea-Cristina Bernat , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-afs@lists.infradead.org Date: Fri, 24 Feb 2017 13:14:45 +0000 Message-ID: <148794208530.28770.18423969130896125671.stgit@warthog.procyon.org.uk> In-Reply-To: <148794199962.28770.5291326312391230868.stgit@warthog.procyon.org.uk> References: <148794199962.28770.5291326312391230868.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.68 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Fri, 24 Feb 2017 13:14:48 +0000 (UTC) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Andreea-Cristina Bernat The use of "rcu_assign_pointer()" is NULLing out the pointer. According to RCU_INIT_POINTER()'s block comment: "1. This use of RCU_INIT_POINTER() is NULLing out the pointer" it is better to use it instead of rcu_assign_pointer() because it has a smaller overhead. The following Coccinelle semantic patch was used: @@ @@ - rcu_assign_pointer + RCU_INIT_POINTER (..., NULL) Signed-off-by: Andreea-Cristina Bernat Signed-off-by: David Howells --- fs/afs/inode.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/afs/inode.c b/fs/afs/inode.c index 8f4e70566e44..5707272adf18 100644 --- a/fs/afs/inode.c +++ b/fs/afs/inode.c @@ -447,7 +447,7 @@ void afs_evict_inode(struct inode *inode) mutex_lock(&vnode->permits_lock); permits = vnode->permits; - rcu_assign_pointer(vnode->permits, NULL); + RCU_INIT_POINTER(vnode->permits, NULL); mutex_unlock(&vnode->permits_lock); if (permits) call_rcu(&permits->rcu, afs_zap_permits);