From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751897AbdK2BOg (ORCPT ); Tue, 28 Nov 2017 20:14:36 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:54964 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751439AbdK2BOe (ORCPT ); Tue, 28 Nov 2017 20:14:34 -0500 Date: Tue, 28 Nov 2017 17:14:29 -0800 From: "Paul E. McKenney" To: Stephen Rothwell Cc: Linux-Next Mailing List , Linux Kernel Mailing List , Liang Lihao Subject: Re: linux-next: Signed-off-by missing for commit in the rcu tree Reply-To: paulmck@linux.vnet.ibm.com References: <20171129115151.40b72764@canb.auug.org.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171129115151.40b72764@canb.auug.org.au> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-GCONF: 00 x-cbid: 17112901-0048-0000-0000-0000020CA2DF X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00008121; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000242; SDB=6.00952667; UDB=6.00481286; IPR=6.00732748; BA=6.00005719; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00018238; XFM=3.00000015; UTC=2017-11-29 01:14:31 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17112901-0049-0000-0000-0000434EC667 Message-Id: <20171129011429.GB3624@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-11-28_13:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 impostorscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1709140000 definitions=main-1711290014 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 29, 2017 at 11:51:51AM +1100, Stephen Rothwell wrote: > Hi Paul, > > Commit > > d7e182c9c324 ("rcu: Remove unnecessary spinlock in rcu_boot_init_percpu_data()") > > is missing a Signed-off-by from its author. Good catch, Stephen! Lihao, would you please get me you Signed-off-by? The patch is below. Thanx, Paul ------------------------------------------------------------------------ commit d7e182c9c32480c1f579dd888ac50e88bfb39596 Author: Liang Lihao Date: Wed Nov 22 19:00:55 2017 +0000 rcu: Remove unnecessary spinlock in rcu_boot_init_percpu_data() Since rcu_boot_init_percpu_data() is only called at boot time, there is no data race and spinlock is not needed. Signed-off-by: Paul E. McKenney diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 69722817d6d6..0abe1db53d70 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -3636,12 +3636,9 @@ static void rcu_init_new_rnp(struct rcu_node *rnp_leaf) static void __init rcu_boot_init_percpu_data(int cpu, struct rcu_state *rsp) { - unsigned long flags; struct rcu_data *rdp = per_cpu_ptr(rsp->rda, cpu); - struct rcu_node *rnp = rcu_get_root(rsp); /* Set up local state, ensuring consistent view of global state. */ - raw_spin_lock_irqsave_rcu_node(rnp, flags); rdp->grpmask = leaf_node_cpu_bit(rdp->mynode, cpu); rdp->dynticks = &per_cpu(rcu_dynticks, cpu); WARN_ON_ONCE(rdp->dynticks->dynticks_nesting != 1); @@ -3649,7 +3646,6 @@ rcu_boot_init_percpu_data(int cpu, struct rcu_state *rsp) rdp->cpu = cpu; rdp->rsp = rsp; rcu_boot_init_nocb_percpu_data(rdp); - raw_spin_unlock_irqrestore_rcu_node(rnp, flags); } /*