From patchwork Sun Jun 23 13:40:56 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Srivatsa S. Bhat" X-Patchwork-Id: 2768101 Return-Path: X-Original-To: patchwork-linux-pm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 57976C0AB1 for ; Sun, 23 Jun 2013 13:55:35 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 71C532018B for ; Sun, 23 Jun 2013 13:55:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 56E3920181 for ; Sun, 23 Jun 2013 13:55:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752280Ab3FWNoX (ORCPT ); Sun, 23 Jun 2013 09:44:23 -0400 Received: from e28smtp05.in.ibm.com ([122.248.162.5]:47955 "EHLO e28smtp05.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752257Ab3FWNoS (ORCPT ); Sun, 23 Jun 2013 09:44:18 -0400 Received: from /spool/local by e28smtp05.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Sun, 23 Jun 2013 19:09:16 +0530 Received: from d28dlp02.in.ibm.com (9.184.220.127) by e28smtp05.in.ibm.com (192.168.1.135) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Sun, 23 Jun 2013 19:09:13 +0530 Received: from d28relay02.in.ibm.com (d28relay02.in.ibm.com [9.184.220.59]) by d28dlp02.in.ibm.com (Postfix) with ESMTP id E9F083940053; Sun, 23 Jun 2013 19:14:12 +0530 (IST) Received: from d28av03.in.ibm.com (d28av03.in.ibm.com [9.184.220.65]) by d28relay02.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r5NDiSxZ26280152; Sun, 23 Jun 2013 19:14:28 +0530 Received: from d28av03.in.ibm.com (loopback [127.0.0.1]) by d28av03.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r5NDiAAJ029361; Sun, 23 Jun 2013 23:44:12 +1000 Received: from srivatsabhat.in.ibm.com ([9.79.195.141]) by d28av03.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id r5NDi8On029309; Sun, 23 Jun 2013 23:44:08 +1000 From: "Srivatsa S. Bhat" Subject: [PATCH 13/45] timer: Use get/put_online_cpus_atomic() to prevent CPU offline To: tglx@linutronix.de, peterz@infradead.org, tj@kernel.org, oleg@redhat.com, paulmck@linux.vnet.ibm.com, rusty@rustcorp.com.au, mingo@kernel.org, akpm@linux-foundation.org, namhyung@kernel.org, walken@google.com, vincent.guittot@linaro.org, laijs@cn.fujitsu.com Cc: rostedt@goodmis.org, wangyun@linux.vnet.ibm.com, xiaoguangrong@linux.vnet.ibm.com, sbw@mit.edu, fweisbec@gmail.com, zhong@linux.vnet.ibm.com, nikunj@linux.vnet.ibm.com, srivatsa.bhat@linux.vnet.ibm.com, linux-pm@vger.kernel.org, linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Thomas Gleixner Date: Sun, 23 Jun 2013 19:10:56 +0530 Message-ID: <20130623134053.19094.23654.stgit@srivatsabhat.in.ibm.com> In-Reply-To: <20130623133642.19094.16038.stgit@srivatsabhat.in.ibm.com> References: <20130623133642.19094.16038.stgit@srivatsabhat.in.ibm.com> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13062313-8256-0000-0000-0000080B6441 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Spam-Status: No, score=-8.0 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Once stop_machine() is gone from the CPU offline path, we won't be able to depend on disabling preemption to prevent CPUs from going offline from under us. Use the get/put_online_cpus_atomic() APIs to prevent CPUs from going offline, while invoking from atomic context. Cc: Thomas Gleixner Signed-off-by: Srivatsa S. Bhat --- kernel/timer.c | 4 ++++ 1 file changed, 4 insertions(+) -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/kernel/timer.c b/kernel/timer.c index 15ffdb3..5db594c 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -729,6 +729,7 @@ __mod_timer(struct timer_list *timer, unsigned long expires, timer_stats_timer_set_start_info(timer); BUG_ON(!timer->function); + get_online_cpus_atomic(); base = lock_timer_base(timer, &flags); ret = detach_if_pending(timer, base, false); @@ -768,6 +769,7 @@ __mod_timer(struct timer_list *timer, unsigned long expires, out_unlock: spin_unlock_irqrestore(&base->lock, flags); + put_online_cpus_atomic(); return ret; } @@ -926,6 +928,7 @@ void add_timer_on(struct timer_list *timer, int cpu) timer_stats_timer_set_start_info(timer); BUG_ON(timer_pending(timer) || !timer->function); + get_online_cpus_atomic(); spin_lock_irqsave(&base->lock, flags); timer_set_base(timer, base); debug_activate(timer, timer->expires); @@ -940,6 +943,7 @@ void add_timer_on(struct timer_list *timer, int cpu) */ wake_up_nohz_cpu(cpu); spin_unlock_irqrestore(&base->lock, flags); + put_online_cpus_atomic(); } EXPORT_SYMBOL_GPL(add_timer_on);