From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756758Ab2HYR40 (ORCPT ); Sat, 25 Aug 2012 13:56:26 -0400 Received: from mga14.intel.com ([143.182.124.37]:52706 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752061Ab2HYR4N (ORCPT ); Sat, 25 Aug 2012 13:56:13 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.80,311,1344236400"; d="scan'208";a="184878874" From: "Fenghua Yu" To: "Ingo Molnar" , "Thomas Gleixner" , "H Peter Anvin" , "Linus Torvalds" , "Andrew Morton" , "Asit K Mallick" , "Tony Luck" , "Arjan Dan De Ven" , "Suresh B Siddha" , "Len Brown" , "Srivatssa S. Bhat" , "Randy Dunlap" , "Chen Gong" , "linux-kernel" , "linux-pm" , "x86" Cc: "Fenghua Yu" Subject: [PATCH v8 05/12] x86, hotplug, suspend: Online CPU0 for suspend or hibernate Date: Sat, 25 Aug 2012 10:41:21 -0700 Message-Id: <1345916488-8355-6-git-send-email-fenghua.yu@intel.com> X-Mailer: git-send-email 1.7.2 In-Reply-To: <1345916488-8355-1-git-send-email-fenghua.yu@intel.com> References: <1345916488-8355-1-git-send-email-fenghua.yu@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Fenghua Yu Because x86 BIOS requires CPU0 to resume from sleep, suspend or hibernate can't be executed if CPU0 is detected offline. To make suspend or hibernate and further resume succeed, CPU0 must be online. Signed-off-by: Fenghua Yu --- arch/x86/power/cpu.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 44 insertions(+), 0 deletions(-) diff --git a/arch/x86/power/cpu.c b/arch/x86/power/cpu.c index 218cdb1..3338609 100644 --- a/arch/x86/power/cpu.c +++ b/arch/x86/power/cpu.c @@ -237,3 +237,47 @@ void restore_processor_state(void) #ifdef CONFIG_X86_32 EXPORT_SYMBOL(restore_processor_state); #endif + +/* + * When bsp_check() is called in hibernate and suspend, cpu hotplug + * is disabled already. So it's unnessary to handle race condition between + * cpumask query and cpu hotplug. + */ +static int bsp_check(void) +{ + if (cpumask_first(cpu_online_mask) != 0) { + printk(KERN_WARNING "CPU0 is offline.\n"); + return -ENODEV; + } + + return 0; +} + +static int bsp_pm_callback(struct notifier_block *nb, unsigned long action, + void *ptr) +{ + int ret = 0; + + switch (action) { + case PM_SUSPEND_PREPARE: + case PM_HIBERNATION_PREPARE: + ret = bsp_check(); + break; + default: + break; + } + return notifier_from_errno(ret); +} + +static int __init bsp_pm_check_init(void) +{ + /* + * Set this bsp_pm_callback as lower priority than + * cpu_hotplug_pm_callback. So cpu_hotplug_pm_callback will be called + * earlier to disable cpu hotplug before bsp online check. + */ + pm_notifier(bsp_pm_callback, -INT_MAX); + return 0; +} + +core_initcall(bsp_pm_check_init); -- 1.7.2