From patchwork Thu Jun 27 19:58:31 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: 255145 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id AFD2F2C0618 for ; Fri, 28 Jun 2013 06:02:21 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755124Ab3F0UCE (ORCPT ); Thu, 27 Jun 2013 16:02:04 -0400 Received: from e23smtp02.au.ibm.com ([202.81.31.144]:40433 "EHLO e23smtp02.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755125Ab3F0UCA (ORCPT ); Thu, 27 Jun 2013 16:02:00 -0400 Received: from /spool/local by e23smtp02.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 28 Jun 2013 05:52:18 +1000 Received: from d23dlp03.au.ibm.com (202.81.31.214) by e23smtp02.au.ibm.com (202.81.31.208) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Fri, 28 Jun 2013 05:52:15 +1000 Received: from d23relay03.au.ibm.com (d23relay03.au.ibm.com [9.190.235.21]) by d23dlp03.au.ibm.com (Postfix) with ESMTP id 6F5BA3578055; Fri, 28 Jun 2013 06:01:55 +1000 (EST) Received: from d23av03.au.ibm.com (d23av03.au.ibm.com [9.190.234.97]) by d23relay03.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r5RK1kSZ2294226; Fri, 28 Jun 2013 06:01:46 +1000 Received: from d23av03.au.ibm.com (loopback [127.0.0.1]) by d23av03.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r5RK1q9J020774; Fri, 28 Jun 2013 06:01:55 +1000 Received: from srivatsabhat.in.ibm.com ([9.79.209.72]) by d23av03.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id r5RK1i0e020595; Fri, 28 Jun 2013 06:01:45 +1000 From: "Srivatsa S. Bhat" Subject: [PATCH v3 34/45] 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, walken@google.com, vincent.guittot@linaro.org, laijs@cn.fujitsu.com, David.Laight@aculab.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, Richard Kuo , Thomas Gleixner , linux-hexagon@vger.kernel.org, "Srivatsa S. Bhat" Date: Fri, 28 Jun 2013 01:28:31 +0530 Message-ID: <20130627195830.29830.70085.stgit@srivatsabhat.in.ibm.com> In-Reply-To: <20130627195136.29830.10445.stgit@srivatsabhat.in.ibm.com> References: <20130627195136.29830.10445.stgit@srivatsabhat.in.ibm.com> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13062719-5490-0000-0000-000003BA31B2 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org 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: Richard Kuo Cc: Thomas Gleixner Cc: linux-hexagon@vger.kernel.org Signed-off-by: Srivatsa S. Bhat --- arch/hexagon/kernel/smp.c | 3 +++ 1 file changed, 3 insertions(+) -- To unsubscribe from this list: send the line "unsubscribe netdev" 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 0e364ca..30d4318 100644 --- a/arch/hexagon/kernel/smp.c +++ b/arch/hexagon/kernel/smp.c @@ -241,9 +241,12 @@ 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)