Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755085Ab3F0UBo (ORCPT ); Thu, 27 Jun 2013 16:01:44 -0400 Received: from e23smtp01.au.ibm.com ([202.81.31.143]:39299 "EHLO e23smtp01.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755048Ab3F0UBl (ORCPT ); Thu, 27 Jun 2013 16:01:41 -0400 From: "Srivatsa S. Bhat" Subject: [PATCH v3 32/45] blackfin/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, Mike Frysinger , Bob Liu , Steven Miao , Thomas Gleixner , uclinux-dist-devel@blackfin.uclinux.org, "Srivatsa S. Bhat" Date: Fri, 28 Jun 2013 01:28:01 +0530 Message-ID: <20130627195801.29830.77286.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 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13062719-1618-0000-0000-0000042B386B Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1417 Lines: 44 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: Mike Frysinger Cc: Bob Liu Cc: Steven Miao Cc: Thomas Gleixner Cc: uclinux-dist-devel@blackfin.uclinux.org Signed-off-by: Srivatsa S. Bhat --- arch/blackfin/mach-common/smp.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/blackfin/mach-common/smp.c b/arch/blackfin/mach-common/smp.c index 1bc2ce6..11496cd 100644 --- a/arch/blackfin/mach-common/smp.c +++ b/arch/blackfin/mach-common/smp.c @@ -238,13 +238,13 @@ void smp_send_stop(void) { cpumask_t callmap; - preempt_disable(); + get_online_cpus_atomic(); cpumask_copy(&callmap, cpu_online_mask); cpumask_clear_cpu(smp_processor_id(), &callmap); if (!cpumask_empty(&callmap)) send_ipi(&callmap, BFIN_IPI_CPU_STOP); - preempt_enable(); + put_online_cpus_atomic(); return; } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/