From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757634AbdJKQq5 (ORCPT ); Wed, 11 Oct 2017 12:46:57 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:50624 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757597AbdJKQqy (ORCPT ); Wed, 11 Oct 2017 12:46:54 -0400 Date: Wed, 11 Oct 2017 09:46:47 -0700 From: "Paul E. McKenney" To: Sebastian Andrzej Siewior Cc: Josh Triplett , Steven Rostedt , Mathieu Desnoyers , Lai Jiangshan , linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/3] srcu: queue work without holding the lock Reply-To: paulmck@linux.vnet.ibm.com References: <20170922152806.22860-1-bigeasy@linutronix.de> <20170922152806.22860-2-bigeasy@linutronix.de> <20170922184610.GT3521@linux.vnet.ibm.com> <20170928160357.anfyrkwq32tyamez@linutronix.de> <20170929011046.GW3521@linux.vnet.ibm.com> <20171010214313.GA19221@linux.vnet.ibm.com> <20171011164012.3vvvy4inogesfjb7@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171011164012.3vvvy4inogesfjb7@linutronix.de> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-GCONF: 00 x-cbid: 17101116-0044-0000-0000-0000039E1854 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00007878; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000236; SDB=6.00929665; UDB=6.00467926; IPR=6.00709936; BA=6.00005634; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00017492; XFM=3.00000015; UTC=2017-10-11 16:46:50 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17101116-0045-0000-0000-000007CD1A03 Message-Id: <20171011164647.GJ3521@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-10-11_06:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1707230000 definitions=main-1710110232 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 11, 2017 at 06:40:12PM +0200, Sebastian Andrzej Siewior wrote: > On 2017-10-10 14:43:13 [-0700], Paul E. McKenney wrote: > > > OK, internally I could get rid of raw_ at the expense of some code bloat, > > > but in the call_srcu() case, the caller might well hold a raw_ lock. > > > > Except that none currently do, so maybe downgrading from raw_ locks is > > a reasonable course of action. Does the following patch help? > > so you revert the raw_ access, this should work. I will apply it > tomorrow and let you know. Indeed. I checked and the current callers of call_srcu() are not doing so while holding raw spinlocks. Now, call_rcu() is quite a different story... Thanx, Paul