From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Srivatsa S. Bhat" Subject: [PATCH v3 31/45] alpha/smp: Use get/put_online_cpus_atomic() to prevent CPU offline Date: Fri, 28 Jun 2013 01:27:47 +0530 Message-ID: <20130627195747.29830.13668.stgit@srivatsabhat.in.ibm.com> References: <20130627195136.29830.10445.stgit@srivatsabhat.in.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20130627195136.29830.10445.stgit@srivatsabhat.in.ibm.com> Sender: linux-kernel-owner@vger.kernel.org To: 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, Richard Henderson , Ivan Kokshaysky , Matt Turner , Thomas Gleixner , linux-alpha@vger.kernel.org"Srivatsa S. Bhat" List-Id: linux-arch.vger.kernel.org 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: Richard Henderson Cc: Ivan Kokshaysky Cc: Matt Turner Cc: Thomas Gleixner Cc: linux-alpha@vger.kernel.org Signed-off-by: Srivatsa S. Bhat --- arch/alpha/kernel/smp.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/arch/alpha/kernel/smp.c b/arch/alpha/kernel/smp.c index 7b60834..e147268 100644 --- a/arch/alpha/kernel/smp.c +++ b/arch/alpha/kernel/smp.c @@ -497,7 +497,6 @@ smp_cpus_done(unsigned int max_cpus) ((bogosum + 2500) / (5000/HZ)) % 100); } - void smp_percpu_timer_interrupt(struct pt_regs *regs) { @@ -681,7 +680,7 @@ ipi_flush_tlb_mm(void *x) void flush_tlb_mm(struct mm_struct *mm) { - preempt_disable(); + get_online_cpus_atomic(); if (mm == current->active_mm) { flush_tlb_current(mm); @@ -693,7 +692,7 @@ flush_tlb_mm(struct mm_struct *mm) if (mm->context[cpu]) mm->context[cpu] = 0; } - preempt_enable(); + put_online_cpus_atomic(); return; } } @@ -702,7 +701,7 @@ flush_tlb_mm(struct mm_struct *mm) printk(KERN_CRIT "flush_tlb_mm: timed out\n"); } - preempt_enable(); + put_online_cpus_atomic(); } EXPORT_SYMBOL(flush_tlb_mm); @@ -730,7 +729,7 @@ flush_tlb_page(struct vm_area_struct *vma, unsigned long addr) struct flush_tlb_page_struct data; struct mm_struct *mm = vma->vm_mm; - preempt_disable(); + get_online_cpus_atomic(); if (mm == current->active_mm) { flush_tlb_current_page(mm, vma, addr); @@ -742,7 +741,7 @@ flush_tlb_page(struct vm_area_struct *vma, unsigned long addr) if (mm->context[cpu]) mm->context[cpu] = 0; } - preempt_enable(); + put_online_cpus_atomic(); return; } } @@ -755,7 +754,7 @@ flush_tlb_page(struct vm_area_struct *vma, unsigned long addr) printk(KERN_CRIT "flush_tlb_page: timed out\n"); } - preempt_enable(); + put_online_cpus_atomic(); } EXPORT_SYMBOL(flush_tlb_page); @@ -786,7 +785,7 @@ flush_icache_user_range(struct vm_area_struct *vma, struct page *page, if ((vma->vm_flags & VM_EXEC) == 0) return; - preempt_disable(); + get_online_cpus_atomic(); if (mm == current->active_mm) { __load_new_mm_context(mm); @@ -798,7 +797,7 @@ flush_icache_user_range(struct vm_area_struct *vma, struct page *page, if (mm->context[cpu]) mm->context[cpu] = 0; } - preempt_enable(); + put_online_cpus_atomic(); return; } } @@ -807,5 +806,5 @@ flush_icache_user_range(struct vm_area_struct *vma, struct page *page, printk(KERN_CRIT "flush_icache_page: timed out\n"); } - preempt_enable(); + put_online_cpus_atomic(); } From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e23smtp07.au.ibm.com ([202.81.31.140]:49773 "EHLO e23smtp07.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755028Ab3F0UBR (ORCPT ); Thu, 27 Jun 2013 16:01:17 -0400 Received: from /spool/local by e23smtp07.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 28 Jun 2013 05:49:39 +1000 From: "Srivatsa S. Bhat" Subject: [PATCH v3 31/45] alpha/smp: Use get/put_online_cpus_atomic() to prevent CPU offline Date: Fri, 28 Jun 2013 01:27:47 +0530 Message-ID: <20130627195747.29830.13668.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> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-arch-owner@vger.kernel.org List-ID: 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, Richard Henderson , Ivan Kokshaysky , Matt Turner , linux-alpha@vger.kernel.org"Srivatsa S. Bhat" Message-ID: <20130627195747.DeCo_DuNCmZPIjHSHSyp_1PS3QNJvkvi0h5Y5_ctnsA@z> 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: Richard Henderson Cc: Ivan Kokshaysky Cc: Matt Turner Cc: Thomas Gleixner Cc: linux-alpha@vger.kernel.org Signed-off-by: Srivatsa S. Bhat --- arch/alpha/kernel/smp.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/arch/alpha/kernel/smp.c b/arch/alpha/kernel/smp.c index 7b60834..e147268 100644 --- a/arch/alpha/kernel/smp.c +++ b/arch/alpha/kernel/smp.c @@ -497,7 +497,6 @@ smp_cpus_done(unsigned int max_cpus) ((bogosum + 2500) / (5000/HZ)) % 100); } - void smp_percpu_timer_interrupt(struct pt_regs *regs) { @@ -681,7 +680,7 @@ ipi_flush_tlb_mm(void *x) void flush_tlb_mm(struct mm_struct *mm) { - preempt_disable(); + get_online_cpus_atomic(); if (mm == current->active_mm) { flush_tlb_current(mm); @@ -693,7 +692,7 @@ flush_tlb_mm(struct mm_struct *mm) if (mm->context[cpu]) mm->context[cpu] = 0; } - preempt_enable(); + put_online_cpus_atomic(); return; } } @@ -702,7 +701,7 @@ flush_tlb_mm(struct mm_struct *mm) printk(KERN_CRIT "flush_tlb_mm: timed out\n"); } - preempt_enable(); + put_online_cpus_atomic(); } EXPORT_SYMBOL(flush_tlb_mm); @@ -730,7 +729,7 @@ flush_tlb_page(struct vm_area_struct *vma, unsigned long addr) struct flush_tlb_page_struct data; struct mm_struct *mm = vma->vm_mm; - preempt_disable(); + get_online_cpus_atomic(); if (mm == current->active_mm) { flush_tlb_current_page(mm, vma, addr); @@ -742,7 +741,7 @@ flush_tlb_page(struct vm_area_struct *vma, unsigned long addr) if (mm->context[cpu]) mm->context[cpu] = 0; } - preempt_enable(); + put_online_cpus_atomic(); return; } } @@ -755,7 +754,7 @@ flush_tlb_page(struct vm_area_struct *vma, unsigned long addr) printk(KERN_CRIT "flush_tlb_page: timed out\n"); } - preempt_enable(); + put_online_cpus_atomic(); } EXPORT_SYMBOL(flush_tlb_page); @@ -786,7 +785,7 @@ flush_icache_user_range(struct vm_area_struct *vma, struct page *page, if ((vma->vm_flags & VM_EXEC) == 0) return; - preempt_disable(); + get_online_cpus_atomic(); if (mm == current->active_mm) { __load_new_mm_context(mm); @@ -798,7 +797,7 @@ flush_icache_user_range(struct vm_area_struct *vma, struct page *page, if (mm->context[cpu]) mm->context[cpu] = 0; } - preempt_enable(); + put_online_cpus_atomic(); return; } } @@ -807,5 +806,5 @@ flush_icache_user_range(struct vm_area_struct *vma, struct page *page, printk(KERN_CRIT "flush_icache_page: timed out\n"); } - preempt_enable(); + put_online_cpus_atomic(); }