From patchwork Tue Jan 22 07:42:17 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: 2016571 Return-Path: X-Original-To: patchwork-linux-pm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id 30B8F3FCDE for ; Tue, 22 Jan 2013 07:49:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754765Ab3AVHoT (ORCPT ); Tue, 22 Jan 2013 02:44:19 -0500 Received: from e28smtp01.in.ibm.com ([122.248.162.1]:54437 "EHLO e28smtp01.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754971Ab3AVHoO (ORCPT ); Tue, 22 Jan 2013 02:44:14 -0500 Received: from /spool/local by e28smtp01.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 22 Jan 2013 13:12:25 +0530 Received: from d28dlp01.in.ibm.com (9.184.220.126) by e28smtp01.in.ibm.com (192.168.1.131) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Tue, 22 Jan 2013 13:12:23 +0530 Received: from d28relay01.in.ibm.com (d28relay01.in.ibm.com [9.184.220.58]) by d28dlp01.in.ibm.com (Postfix) with ESMTP id 9FBDCE004D; Tue, 22 Jan 2013 13:14:36 +0530 (IST) Received: from d28av01.in.ibm.com (d28av01.in.ibm.com [9.184.220.63]) by d28relay01.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r0M7i7CA46399530; Tue, 22 Jan 2013 13:14:07 +0530 Received: from d28av01.in.ibm.com (loopback [127.0.0.1]) by d28av01.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r0M7i23m012990; Tue, 22 Jan 2013 07:44:09 GMT Received: from srivatsabhat.in.ibm.com (srivatsabhat.in.ibm.com [9.124.35.112]) by d28av01.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id r0M7i2ib012974; Tue, 22 Jan 2013 07:44:02 GMT From: "Srivatsa S. Bhat" Subject: [PATCH v5 33/45] hexagon/smp: 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 Cc: rostedt@goodmis.org, wangyun@linux.vnet.ibm.com, xiaoguangrong@linux.vnet.ibm.com, rjw@sisk.pl, sbw@mit.edu, fweisbec@gmail.com, linux@arm.linux.org.uk, nikunj@linux.vnet.ibm.com, srivatsa.bhat@linux.vnet.ibm.com, linux-pm@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, netdev@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Date: Tue, 22 Jan 2013 13:12:17 +0530 Message-ID: <20130122074213.13822.71590.stgit@srivatsabhat.in.ibm.com> In-Reply-To: <20130122073210.13822.50434.stgit@srivatsabhat.in.ibm.com> References: <20130122073210.13822.50434.stgit@srivatsabhat.in.ibm.com> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13012207-4790-0000-0000-000006940976 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Once stop_machine() is gone from the CPU offline path, we won't be able to depend on preempt_disable() or local_irq_disable() 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: Richard Kuo Cc: linux-hexagon@vger.kernel.org Signed-off-by: Srivatsa S. Bhat --- arch/hexagon/kernel/smp.c | 5 +++++ 1 file changed, 5 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/arch/hexagon/kernel/smp.c b/arch/hexagon/kernel/smp.c index 8e095df..ec87de9 100644 --- a/arch/hexagon/kernel/smp.c +++ b/arch/hexagon/kernel/smp.c @@ -112,6 +112,7 @@ void send_ipi(const struct cpumask *cpumask, enum ipi_message_type msg) unsigned long cpu; unsigned long retval; + get_online_cpus_atomic(); local_irq_save(flags); for_each_cpu(cpu, cpumask) { @@ -128,6 +129,7 @@ void send_ipi(const struct cpumask *cpumask, enum ipi_message_type msg) } local_irq_restore(flags); + put_online_cpus_atomic(); } static struct irqaction ipi_intdesc = { @@ -241,9 +243,12 @@ void smp_send_reschedule(int cpu) void smp_send_stop(void) { struct cpumask targets; + + get_online_cpus_atomic(); cpumask_copy(&targets, cpu_online_mask); cpumask_clear_cpu(smp_processor_id(), &targets); send_ipi(&targets, IPI_CPU_STOP); + put_online_cpus_atomic(); } void arch_send_call_function_single_ipi(int cpu)