Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755236Ab3F0UDI (ORCPT ); Thu, 27 Jun 2013 16:03:08 -0400 Received: from e23smtp02.au.ibm.com ([202.81.31.144]:40507 "EHLO e23smtp02.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754356Ab3F0UDE (ORCPT ); Thu, 27 Jun 2013 16:03:04 -0400 From: "Srivatsa S. Bhat" Subject: [PATCH v3 39/45] 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, 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, David Howells , Koichi Yasutake , linux-am33-list@redhat.com, "Srivatsa S. Bhat" Date: Fri, 28 Jun 2013 01:29:35 +0530 Message-ID: <20130627195935.29830.37304.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: 13062719-5490-0000-0000-000003BA3209 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3883 Lines: 133 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: David Howells Cc: Koichi Yasutake Cc: linux-am33-list@redhat.com Signed-off-by: Srivatsa S. Bhat --- arch/mn10300/mm/cache-smp.c | 3 +++ arch/mn10300/mm/tlb-smp.c | 17 +++++++++-------- 2 files changed, 12 insertions(+), 8 deletions(-) diff --git a/arch/mn10300/mm/cache-smp.c b/arch/mn10300/mm/cache-smp.c index 2d23b9e..406357d 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 @@ -91,6 +92,7 @@ void smp_cache_interrupt(void) void smp_cache_call(unsigned long opr_mask, unsigned long start, unsigned long end) { + get_online_cpus_atomic(); smp_cache_mask = opr_mask; smp_cache_start = start; smp_cache_end = end; @@ -102,4 +104,5 @@ 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..8856fd3 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 @@ -61,7 +62,7 @@ void smp_flush_tlb(void *unused) { unsigned long cpu_id; - cpu_id = get_cpu(); + cpu_id = get_online_cpus_atomic(); if (!cpumask_test_cpu(cpu_id, &flush_cpumask)) /* This was a BUG() but until someone can quote me the line @@ -82,7 +83,7 @@ void smp_flush_tlb(void *unused) cpumask_clear_cpu(cpu_id, &flush_cpumask); smp_mb__after_clear_bit(); out: - put_cpu(); + put_online_cpus_atomic(); } /** @@ -144,7 +145,7 @@ 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 +153,7 @@ 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 +164,7 @@ 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 +172,7 @@ 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 +185,7 @@ 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 +193,7 @@ 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(); } /** -- 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/