From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mathieu Desnoyers Subject: Re: [RFC PATCH for 4.15 18/24] membarrier: provide SHARED_EXPEDITED command Date: Wed, 15 Nov 2017 01:36:11 +0000 (UTC) Message-ID: <1572576576.15297.1510709771637.JavaMail.zimbra@efficios.com> References: <20171114200414.2188-1-mathieu.desnoyers@efficios.com> <20171114200414.2188-19-mathieu.desnoyers@efficios.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20171114200414.2188-19-mathieu.desnoyers-vg+e7yoeK/dWk0Htik3J/w@public.gmane.org> Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Peter Zijlstra , "Paul E. McKenney" , Boqun Feng , Andy Lutomirski , Dave Watson Cc: linux-kernel , linux-api , Paul Turner , Andrew Morton , Russell King , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Andrew Hunter , Andi Kleen , Chris Lameter , Ben Maurer , rostedt , Josh Triplett , Linus Torvalds , Catalin Marinas , Will Deacon , Michael Kerrisk , maged michael , Avi Kivity Benjamin Herrenschmidt List-Id: linux-api@vger.kernel.org ----- On Nov 14, 2017, at 3:04 PM, Mathieu Desnoyers mathieu.desnoyers-vg+e7yoeK/dWk0Htik3J/w@public.gmane.org wrote: [...] > + if (!fallback) { > + smp_call_function_many(tmpmask, ipi_mb, NULL, 1); > + free_cpumask_var(tmpmask); > + } Testing with preempt debugging options showed that I need to disable preemption around smp_call_function_many(). The membarrier private expedited command in 4.14 is also affected. I will add a fix to the series covering that case separately, and CC stable. Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755381AbdKOBfe (ORCPT ); Tue, 14 Nov 2017 20:35:34 -0500 Received: from mail.efficios.com ([167.114.142.141]:60607 "EHLO mail.efficios.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754313AbdKOBf1 (ORCPT ); Tue, 14 Nov 2017 20:35:27 -0500 Date: Wed, 15 Nov 2017 01:36:11 +0000 (UTC) From: Mathieu Desnoyers To: Peter Zijlstra , "Paul E. McKenney" , Boqun Feng , Andy Lutomirski , Dave Watson Cc: linux-kernel , linux-api , Paul Turner , Andrew Morton , Russell King , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Andrew Hunter , Andi Kleen , Chris Lameter , Ben Maurer , rostedt , Josh Triplett , Linus Torvalds , Catalin Marinas , Will Deacon , Michael Kerrisk , maged michael , Avi Kivity , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Andrea Parri , x86 Message-ID: <1572576576.15297.1510709771637.JavaMail.zimbra@efficios.com> In-Reply-To: <20171114200414.2188-19-mathieu.desnoyers@efficios.com> References: <20171114200414.2188-1-mathieu.desnoyers@efficios.com> <20171114200414.2188-19-mathieu.desnoyers@efficios.com> Subject: Re: [RFC PATCH for 4.15 18/24] membarrier: provide SHARED_EXPEDITED command MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Originating-IP: [167.114.142.141] X-Mailer: Zimbra 8.7.11_GA_1854 (ZimbraWebClient - FF52 (Linux)/8.7.11_GA_1854) Thread-Topic: membarrier: provide SHARED_EXPEDITED command Thread-Index: zBRiduKsAyztu63+HnY8oJEXUQnr7A== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ----- On Nov 14, 2017, at 3:04 PM, Mathieu Desnoyers mathieu.desnoyers@efficios.com wrote: [...] > + if (!fallback) { > + smp_call_function_many(tmpmask, ipi_mb, NULL, 1); > + free_cpumask_var(tmpmask); > + } Testing with preempt debugging options showed that I need to disable preemption around smp_call_function_many(). The membarrier private expedited command in 4.14 is also affected. I will add a fix to the series covering that case separately, and CC stable. Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com