From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752121AbbEAQ3V (ORCPT ); Fri, 1 May 2015 12:29:21 -0400 Received: from foss.arm.com ([217.140.101.70]:38914 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751966AbbEAQ3U (ORCPT ); Fri, 1 May 2015 12:29:20 -0400 Date: Fri, 1 May 2015 17:29:15 +0100 From: Catalin Marinas To: "Paul E. McKenney" Cc: will.deacon@arm.com, linux@arm.linux.org.uk, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, mingo@kernel.org Subject: Re: [PATCH arm 1/2] arm64: Use common outgoing-CPU-notification code Message-ID: <20150501162915.GI27755@e104818-lin.cambridge.arm.com> References: <20150423200603.GA9473@linux.vnet.ibm.com> <1429819654-10498-1-git-send-email-paulmck@linux.vnet.ibm.com> <20150430095055.GI18867@e104818-lin.cambridge.arm.com> <20150501150848.GC5381@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150501150848.GC5381@linux.vnet.ibm.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 01, 2015 at 08:08:48AM -0700, Paul E. McKenney wrote: > On Thu, Apr 30, 2015 at 10:50:55AM +0100, Catalin Marinas wrote: > > On Thu, Apr 23, 2015 at 01:07:33PM -0700, Paul E. McKenney wrote: > > > diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c > > > index 328b8ce4b007..6dc727a6e73e 100644 > > > --- a/arch/arm64/kernel/smp.c > > > +++ b/arch/arm64/kernel/smp.c > > > @@ -252,15 +252,13 @@ static int op_cpu_kill(unsigned int cpu) > > > return cpu_ops[cpu]->cpu_kill(cpu); > > > } > > > > > > -static DECLARE_COMPLETION(cpu_died); > > > - > > > /* > > > * called on the thread which is asking for a CPU to be shutdown - > > > * waits until shutdown has completed, or it is timed out. > > > */ > > > void __cpu_die(unsigned int cpu) > > > { > > > - if (!wait_for_completion_timeout(&cpu_died, msecs_to_jiffies(5000))) { > > > + if (!cpu_wait_death(cpu, 5)) { > > > pr_crit("CPU%u: cpu didn't die\n", cpu); > > > return; > > > } > > > @@ -293,7 +291,7 @@ void cpu_die(void) > > > local_irq_disable(); > > > > > > /* Tell __cpu_die() that this CPU is now safe to dispose of */ > > > - complete(&cpu_died); > > > + (void)cpu_report_death(); > > > > > > /* > > > * Actually shutdown the CPU. This must never fail. The specific hotplug > > > > Are these functions are only defined when HOTPLUG_CPU is enabled? On > > arm64 we can end up with this option disabled if SUSPEND is disabled. > > Yep, only with HOTPLUG_CPU. And yes, both SUSPEND and HIBERNATION can > force HOTPLUG_CPU, so if you have neiter SUSPEND nor HIBERNATION, you > won't have HOTPLUG_CPU. This -should- be OK, because you should also > not have __cpu_die() if !HOTPLUG_CPU. Ah, you are right. I got myself confused. So is this patch ready for upstreaming or just for our information? -- Catalin