From patchwork Mon Feb 18 12:43:06 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: 221285 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 7A0442C04EE for ; Mon, 18 Feb 2013 23:45:34 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932130Ab3BRMpT (ORCPT ); Mon, 18 Feb 2013 07:45:19 -0500 Received: from e23smtp01.au.ibm.com ([202.81.31.143]:58127 "EHLO e23smtp01.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756757Ab3BRMpP (ORCPT ); Mon, 18 Feb 2013 07:45:15 -0500 Received: from /spool/local by e23smtp01.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 18 Feb 2013 22:39:39 +1000 Received: from d23dlp02.au.ibm.com (202.81.31.213) by e23smtp01.au.ibm.com (202.81.31.207) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Mon, 18 Feb 2013 22:39:36 +1000 Received: from d23relay03.au.ibm.com (d23relay03.au.ibm.com [9.190.235.21]) by d23dlp02.au.ibm.com (Postfix) with ESMTP id 9F1072BB004F; Mon, 18 Feb 2013 23:45:11 +1100 (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 r1ICj9T55374316; Mon, 18 Feb 2013 23:45:09 +1100 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 r1ICj8uu021788; Mon, 18 Feb 2013 23:45:11 +1100 Received: from srivatsabhat.in.ibm.com (srivatsabhat.in.ibm.com [9.124.35.204] (may be forged)) by d23av03.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id r1ICj272021694; Mon, 18 Feb 2013 23:45:03 +1100 From: "Srivatsa S. Bhat" Subject: [PATCH v6 34/46] 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, walken@google.com, vincent.guittot@linaro.org Date: Mon, 18 Feb 2013 18:13:06 +0530 Message-ID: <20130218124305.26245.64570.stgit@srivatsabhat.in.ibm.com> In-Reply-To: <20130218123714.26245.61816.stgit@srivatsabhat.in.ibm.com> References: <20130218123714.26245.61816.stgit@srivatsabhat.in.ibm.com> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13021812-1618-0000-0000-0000035BC485 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 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 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 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)