From patchwork Tue Jan 22 07:43:16 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: 2016941 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) by patchwork1.kernel.org (Postfix) with ESMTP id 741643FCDE for ; Tue, 22 Jan 2013 07:56:02 +0000 (UTC) Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1TxYfM-0007Jb-Ul; Tue, 22 Jan 2013 07:53:09 +0000 Received: from e23smtp08.au.ibm.com ([202.81.31.141]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1TxYXq-0008Ig-3L for linux-arm-kernel@lists.infradead.org; Tue, 22 Jan 2013 07:45:24 +0000 Received: from /spool/local by e23smtp08.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 22 Jan 2013 17:43:47 +1000 Received: from d23dlp01.au.ibm.com (202.81.31.203) by e23smtp08.au.ibm.com (202.81.31.205) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Tue, 22 Jan 2013 17:43:45 +1000 Received: from d23relay05.au.ibm.com (d23relay05.au.ibm.com [9.190.235.152]) by d23dlp01.au.ibm.com (Postfix) with ESMTP id 0F64C2CE804D for ; Tue, 22 Jan 2013 18:45:17 +1100 (EST) Received: from d23av03.au.ibm.com (d23av03.au.ibm.com [9.190.234.97]) by d23relay05.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r0M7XMi264159834 for ; Tue, 22 Jan 2013 18:33:22 +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 r0M7jE9I021107 for ; Tue, 22 Jan 2013 18:45:16 +1100 Received: from srivatsabhat.in.ibm.com (srivatsabhat.in.ibm.com [9.124.35.112]) by d23av03.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id r0M7j1DQ020545; Tue, 22 Jan 2013 18:45:02 +1100 From: "Srivatsa S. Bhat" Subject: [PATCH v5 37/45] mn10300: 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: Tue, 22 Jan 2013 13:13:16 +0530 Message-ID: <20130122074312.13822.41323.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: 13012207-5140-0000-0000-000002A8FBB1 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130122_024522_853210_3669FAC7 X-CRM114-Status: GOOD ( 14.64 ) X-Spam-Score: -4.6 (----) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-4.6 points) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at http://www.dnswl.org/, high trust [202.81.31.141 listed in list.dnswl.org] 3.0 KHOP_BIG_TO_CC Sent to 10+ recipients instaed of Bcc or a list -0.7 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] 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, linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@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: David Howells Cc: Koichi Yasutake Cc: linux-am33-list@redhat.com Signed-off-by: Srivatsa S. Bhat --- arch/mn10300/kernel/smp.c | 2 ++ arch/mn10300/mm/cache-smp.c | 5 +++++ arch/mn10300/mm/tlb-smp.c | 15 +++++++++------ 3 files changed, 16 insertions(+), 6 deletions(-) diff --git a/arch/mn10300/kernel/smp.c b/arch/mn10300/kernel/smp.c index 5d7e152..9dfa172 100644 --- a/arch/mn10300/kernel/smp.c +++ b/arch/mn10300/kernel/smp.c @@ -349,9 +349,11 @@ void send_IPI_allbutself(int irq) { cpumask_t cpumask; + get_online_cpus_atomic(); cpumask_copy(&cpumask, cpu_online_mask); cpumask_clear_cpu(smp_processor_id(), &cpumask); send_IPI_mask(&cpumask, irq); + put_online_cpus_atomic(); } void arch_send_call_function_ipi_mask(const struct cpumask *mask) diff --git a/arch/mn10300/mm/cache-smp.c b/arch/mn10300/mm/cache-smp.c index 2d23b9e..47ca1c9 100644 --- a/arch/mn10300/mm/cache-smp.c +++ b/arch/mn10300/mm/cache-smp.c @@ -13,6 +13,7 @@ #include #include #include +#include #include #include #include @@ -94,6 +95,8 @@ void smp_cache_call(unsigned long opr_mask, smp_cache_mask = opr_mask; smp_cache_start = start; smp_cache_end = end; + + get_online_cpus_atomic(); cpumask_copy(&smp_cache_ipi_map, cpu_online_mask); cpumask_clear_cpu(smp_processor_id(), &smp_cache_ipi_map); @@ -102,4 +105,6 @@ void smp_cache_call(unsigned long opr_mask, while (!cpumask_empty(&smp_cache_ipi_map)) /* nothing. lockup detection does not belong here */ mb(); + + put_online_cpus_atomic(); } diff --git a/arch/mn10300/mm/tlb-smp.c b/arch/mn10300/mm/tlb-smp.c index 3e57faf..d47304d 100644 --- a/arch/mn10300/mm/tlb-smp.c +++ b/arch/mn10300/mm/tlb-smp.c @@ -23,6 +23,7 @@ #include #include #include +#include #include #include #include @@ -105,6 +106,7 @@ static void flush_tlb_others(cpumask_t cpumask, struct mm_struct *mm, BUG_ON(cpumask_empty(&cpumask)); BUG_ON(cpumask_test_cpu(smp_processor_id(), &cpumask)); + get_online_cpus_atomic(); cpumask_and(&tmp, &cpumask, cpu_online_mask); BUG_ON(!cpumask_equal(&cpumask, &tmp)); @@ -134,6 +136,7 @@ static void flush_tlb_others(cpumask_t cpumask, struct mm_struct *mm, flush_mm = NULL; flush_va = 0; spin_unlock(&tlbstate_lock); + put_online_cpus_atomic(); } /** @@ -144,7 +147,7 @@ void flush_tlb_mm(struct mm_struct *mm) { cpumask_t cpu_mask; - preempt_disable(); + get_online_cpus_atomic(); cpumask_copy(&cpu_mask, mm_cpumask(mm)); cpumask_clear_cpu(smp_processor_id(), &cpu_mask); @@ -152,7 +155,7 @@ void flush_tlb_mm(struct mm_struct *mm) if (!cpumask_empty(&cpu_mask)) flush_tlb_others(cpu_mask, mm, FLUSH_ALL); - preempt_enable(); + put_online_cpus_atomic(); } /** @@ -163,7 +166,7 @@ void flush_tlb_current_task(void) struct mm_struct *mm = current->mm; cpumask_t cpu_mask; - preempt_disable(); + get_online_cpus_atomic(); cpumask_copy(&cpu_mask, mm_cpumask(mm)); cpumask_clear_cpu(smp_processor_id(), &cpu_mask); @@ -171,7 +174,7 @@ void flush_tlb_current_task(void) if (!cpumask_empty(&cpu_mask)) flush_tlb_others(cpu_mask, mm, FLUSH_ALL); - preempt_enable(); + put_online_cpus_atomic(); } /** @@ -184,7 +187,7 @@ void flush_tlb_page(struct vm_area_struct *vma, unsigned long va) struct mm_struct *mm = vma->vm_mm; cpumask_t cpu_mask; - preempt_disable(); + get_online_cpus_atomic(); cpumask_copy(&cpu_mask, mm_cpumask(mm)); cpumask_clear_cpu(smp_processor_id(), &cpu_mask); @@ -192,7 +195,7 @@ void flush_tlb_page(struct vm_area_struct *vma, unsigned long va) if (!cpumask_empty(&cpu_mask)) flush_tlb_others(cpu_mask, mm, va); - preempt_enable(); + put_online_cpus_atomic(); } /**