From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751197AbaJIRFv (ORCPT ); Thu, 9 Oct 2014 13:05:51 -0400 Received: from mail.skyhub.de ([78.46.96.112]:52915 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750896AbaJIRFn (ORCPT ); Thu, 9 Oct 2014 13:05:43 -0400 Date: Thu, 9 Oct 2014 19:05:34 +0200 From: Borislav Petkov To: Thomas Gleixner Cc: LKML , Ingo Molnar , Peter Zijlstra , Rusty Russell , Paul McKenney , "Srivatsa S. Bhat" , Arjan van de Veen , Paul Turner , Magnus Damm , Richard Weinberger , =?utf-8?B?SsO2cmcgUsO2ZGVs?= Subject: Re: [patch 05/40] cpu: Restructure cpu_down code Message-ID: <20141009170533.GB15050@pd.tnic> References: <20130131120348.372374706@linutronix.de> <20130131120741.823640323@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20130131120741.823640323@linutronix.de> 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 Thu, Jan 31, 2013 at 12:11:15PM -0000, Thomas Gleixner wrote: > Split out into separate functions, so we can convert it to a state machine. > > Signed-off-by: Thomas Gleixner Refreshed: >>From linux-kernel-owner@vger.kernel.org Thu Jan 31 13:11:32 2013 Message-Id: <20130131120741.823640323@linutronix.de> User-Agent: quilt/0.48-1 Date: Thu, 31 Jan 2013 12:11:15 -0000 From: Thomas Gleixner To: LKML Cc: Ingo Molnar , Peter Zijlstra , Rusty Russell , Paul McKenney , "Srivatsa S. Bhat" , Arjan van de Veen , Paul Turner , Richard Weinberger , Magnus Damm Subject: [patch 05/40] cpu: Restructure cpu_down code MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=utf-8 Status: RO Split out into separate functions, so we can convert it to a state machine. Signed-off-by: Thomas Gleixner --- kernel/cpu.c | 69 ++++++++++++++++++++++++++++++++++++++++------------------- 1 file changed, 47 insertions(+), 22 deletions(-) Index: linux/kernel/cpu.c =================================================================== --- linux.orig/kernel/cpu.c 2014-10-09 18:54:47.251793646 +0200 +++ linux/kernel/cpu.c 2014-10-09 19:00:46.743791277 +0200 @@ -214,6 +214,43 @@ static int cpu_notify(unsigned long val, return __cpu_notify(val, cpu, -1, NULL); } +/* Notifier wrappers for transitioning to state machine */ +static int notify_prepare(unsigned int cpu) +{ + int nr_calls = 0; + int ret; + + ret = __cpu_notify(CPU_UP_PREPARE, cpu, -1, &nr_calls); + if (ret) { + nr_calls--; + printk(KERN_WARNING "%s: attempt to bring up CPU %u failed\n", + __func__, cpu); + __cpu_notify(CPU_UP_CANCELED, cpu, nr_calls, NULL); + } + return ret; +} + +static int notify_online(unsigned int cpu) +{ + cpu_notify(CPU_ONLINE, cpu); + return 0; +} + +static int bringup_cpu(unsigned int cpu) +{ + struct task_struct *idle = idle_thread_get(cpu); + int ret; + + /* Arch-specific enabling code. */ + ret = __cpu_up(cpu, idle); + if (ret) { + cpu_notify(CPU_UP_CANCELED, cpu); + return ret; + } + BUG_ON(!cpu_online(cpu)); + return 0; +} + #ifdef CONFIG_HOTPLUG_CPU static void cpu_notify_nofail(unsigned long val, unsigned int cpu) @@ -421,7 +458,7 @@ EXPORT_SYMBOL(cpu_down); static int _cpu_up(unsigned int cpu, int tasks_frozen) { struct task_struct *idle; - int ret, nr_calls = 0; + int ret; cpu_hotplug_begin(); @@ -436,35 +473,24 @@ static int _cpu_up(unsigned int cpu, int goto out; } + cpuhp_tasks_frozen = tasks_frozen; + ret = smpboot_create_threads(cpu); if (ret) goto out; - cpuhp_tasks_frozen = tasks_frozen; - - ret = __cpu_notify(CPU_UP_PREPARE, cpu, -1, &nr_calls); - if (ret) { - nr_calls--; - pr_warn("%s: attempt to bring up CPU %u failed\n", - __func__, cpu); - goto out_notify; - } + ret = notify_prepare(cpu); + if (ret) + goto out; - /* Arch-specific enabling code. */ - ret = __cpu_up(cpu, idle); - if (ret != 0) - goto out_notify; - BUG_ON(!cpu_online(cpu)); + ret = bringup_cpu(cpu); + if (ret) + goto out; /* Wake the per cpu threads */ smpboot_unpark_threads(cpu); - /* Now call notifier in preparation. */ - cpu_notify(CPU_ONLINE, cpu); - -out_notify: - if (ret != 0) - __cpu_notify(CPU_UP_CANCELED, cpu, nr_calls, NULL); + notify_online(cpu); out: cpu_hotplug_done(); -- Regards/Gruss, Boris. Sent from a fat crate under my desk. Formatting is fine. --