From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751298AbaCWSdf (ORCPT ); Sun, 23 Mar 2014 14:33:35 -0400 Received: from mail-pa0-f47.google.com ([209.85.220.47]:48944 "EHLO mail-pa0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751134AbaCWSdd (ORCPT ); Sun, 23 Mar 2014 14:33:33 -0400 From: Monam Agarwal To: davem@davemloft.net, jasowang@redhat.com, mst@redhat.com, xemul@parallels.com, wuzhy@linux.vnet.ibm.com, therbert@google.com, yamato@redhat.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] drivers/net: Use RCU_INIT_POINTER(x, NULL) in tun.c Date: Mon, 24 Mar 2014 00:02:32 +0530 Message-Id: <1395599552-7486-1-git-send-email-monamagarwal123@gmail.com> X-Mailer: git-send-email 1.7.9.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch replaces rcu_assign_pointer(x, NULL) with RCU_INIT_POINTER(x, NULL) The rcu_assign_pointer() ensures that the initialization of a structure is carried out before storing a pointer to that structure. And in the case of the NULL pointer, there is no structure to initialize. So, rcu_assign_pointer(p, NULL) can be safely converted to RCU_INIT_POINTER(p, NULL) Signed-off-by: Monam Agarwal --- drivers/net/tun.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 26f8635..ee328ba 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -452,7 +452,7 @@ static void __tun_detach(struct tun_file *tfile, bool clean) --tun->numqueues; if (clean) { - rcu_assign_pointer(tfile->tun, NULL); + RCU_INIT_POINTER(tfile->tun, NULL); sock_put(&tfile->sk); } else tun_disable_queue(tun, tfile); @@ -499,12 +499,12 @@ static void tun_detach_all(struct net_device *dev) tfile = rtnl_dereference(tun->tfiles[i]); BUG_ON(!tfile); wake_up_all(&tfile->wq.wait); - rcu_assign_pointer(tfile->tun, NULL); + RCU_INIT_POINTER(tfile->tun, NULL); --tun->numqueues; } list_for_each_entry(tfile, &tun->disabled, next) { wake_up_all(&tfile->wq.wait); - rcu_assign_pointer(tfile->tun, NULL); + RCU_INIT_POINTER(tfile->tun, NULL); } BUG_ON(tun->numqueues != 0); @@ -2194,7 +2194,7 @@ static int tun_chr_open(struct inode *inode, struct file * file) &tun_proto); if (!tfile) return -ENOMEM; - rcu_assign_pointer(tfile->tun, NULL); + RCU_INIT_POINTER(tfile->tun, NULL); tfile->net = get_net(current->nsproxy->net_ns); tfile->flags = 0; tfile->ifindex = 0; -- 1.7.9.5