From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756671Ab3BRMo7 (ORCPT ); Mon, 18 Feb 2013 07:44:59 -0500 Received: from e23smtp03.au.ibm.com ([202.81.31.145]:53432 "EHLO e23smtp03.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932134Ab3BRMoz (ORCPT ); Mon, 18 Feb 2013 07:44:55 -0500 From: "Srivatsa S. Bhat" Subject: [PATCH v6 32/46] 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 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 18:12:42 +0530 Message-ID: <20130218124242.26245.39810.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 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13021812-6102-0000-0000-0000030577B7 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@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: Mike Frysinger Cc: Bob Liu Cc: Steven Miao Cc: uclinux-dist-devel@blackfin.uclinux.org Signed-off-by: Srivatsa S. Bhat --- arch/blackfin/mach-common/smp.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/blackfin/mach-common/smp.c b/arch/blackfin/mach-common/smp.c index bb61ae4..6cc6d7a 100644 --- a/arch/blackfin/mach-common/smp.c +++ b/arch/blackfin/mach-common/smp.c @@ -194,6 +194,7 @@ void send_ipi(const struct cpumask *cpumask, enum ipi_message_type msg) struct ipi_data *bfin_ipi_data; unsigned long flags; + get_online_cpus_atomic(); local_irq_save(flags); smp_mb(); for_each_cpu(cpu, cpumask) { @@ -205,6 +206,7 @@ void send_ipi(const struct cpumask *cpumask, enum ipi_message_type msg) } local_irq_restore(flags); + put_online_cpus_atomic(); } void arch_send_call_function_single_ipi(int cpu) @@ -238,13 +240,13 @@ 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; } From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e23smtp09.au.ibm.com (e23smtp09.au.ibm.com [202.81.31.142]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e23smtp09.au.ibm.com", Issuer "GeoTrust SSL CA" (not verified)) by ozlabs.org (Postfix) with ESMTPS id D31392C0314 for ; Mon, 18 Feb 2013 23:44:50 +1100 (EST) Received: from /spool/local by e23smtp09.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 18 Feb 2013 22:37:44 +1000 Received: from d23relay05.au.ibm.com (d23relay05.au.ibm.com [9.190.235.152]) by d23dlp02.au.ibm.com (Postfix) with ESMTP id 7A4822BB0051 for ; Mon, 18 Feb 2013 23:44:47 +1100 (EST) Received: from d23av01.au.ibm.com (d23av01.au.ibm.com [9.190.234.96]) by d23relay05.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r1ICWL7v41353458 for ; Mon, 18 Feb 2013 23:32:21 +1100 Received: from d23av01.au.ibm.com (loopback [127.0.0.1]) by d23av01.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r1ICijcJ004962 for ; Mon, 18 Feb 2013 23:44:47 +1100 From: "Srivatsa S. Bhat" Subject: [PATCH v6 32/46] 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 Date: Mon, 18 Feb 2013 18:12:42 +0530 Message-ID: <20130218124242.26245.39810.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> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Cc: linux-arch@vger.kernel.org, linux@arm.linux.org.uk, nikunj@linux.vnet.ibm.com, linux-pm@vger.kernel.org, fweisbec@gmail.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, rostedt@goodmis.org, xiaoguangrong@linux.vnet.ibm.com, rjw@sisk.pl, sbw@mit.edu, wangyun@linux.vnet.ibm.com, srivatsa.bhat@linux.vnet.ibm.com, netdev@vger.kernel.org, vincent.guittot@linaro.org, walken@google.com, linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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: Mike Frysinger Cc: Bob Liu Cc: Steven Miao Cc: uclinux-dist-devel@blackfin.uclinux.org Signed-off-by: Srivatsa S. Bhat --- arch/blackfin/mach-common/smp.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/blackfin/mach-common/smp.c b/arch/blackfin/mach-common/smp.c index bb61ae4..6cc6d7a 100644 --- a/arch/blackfin/mach-common/smp.c +++ b/arch/blackfin/mach-common/smp.c @@ -194,6 +194,7 @@ void send_ipi(const struct cpumask *cpumask, enum ipi_message_type msg) struct ipi_data *bfin_ipi_data; unsigned long flags; + get_online_cpus_atomic(); local_irq_save(flags); smp_mb(); for_each_cpu(cpu, cpumask) { @@ -205,6 +206,7 @@ void send_ipi(const struct cpumask *cpumask, enum ipi_message_type msg) } local_irq_restore(flags); + put_online_cpus_atomic(); } void arch_send_call_function_single_ipi(int cpu) @@ -238,13 +240,13 @@ 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; } From mboxrd@z Thu Jan 1 00:00:00 1970 From: srivatsa.bhat@linux.vnet.ibm.com (Srivatsa S. Bhat) Date: Mon, 18 Feb 2013 18:12:42 +0530 Subject: [PATCH v6 32/46] blackfin/smp: Use get/put_online_cpus_atomic() to prevent CPU offline In-Reply-To: <20130218123714.26245.61816.stgit@srivatsabhat.in.ibm.com> References: <20130218123714.26245.61816.stgit@srivatsabhat.in.ibm.com> Message-ID: <20130218124242.26245.39810.stgit@srivatsabhat.in.ibm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.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: Mike Frysinger Cc: Bob Liu Cc: Steven Miao Cc: uclinux-dist-devel at blackfin.uclinux.org Signed-off-by: Srivatsa S. Bhat --- arch/blackfin/mach-common/smp.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/blackfin/mach-common/smp.c b/arch/blackfin/mach-common/smp.c index bb61ae4..6cc6d7a 100644 --- a/arch/blackfin/mach-common/smp.c +++ b/arch/blackfin/mach-common/smp.c @@ -194,6 +194,7 @@ void send_ipi(const struct cpumask *cpumask, enum ipi_message_type msg) struct ipi_data *bfin_ipi_data; unsigned long flags; + get_online_cpus_atomic(); local_irq_save(flags); smp_mb(); for_each_cpu(cpu, cpumask) { @@ -205,6 +206,7 @@ void send_ipi(const struct cpumask *cpumask, enum ipi_message_type msg) } local_irq_restore(flags); + put_online_cpus_atomic(); } void arch_send_call_function_single_ipi(int cpu) @@ -238,13 +240,13 @@ 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; }