From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e23smtp01.au.ibm.com (e23smtp01.au.ibm.com [202.81.31.143]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e23smtp01.au.ibm.com", Issuer "GeoTrust SSL CA" (not verified)) by ozlabs.org (Postfix) with ESMTPS id 73A142C0880 for ; Fri, 28 Jun 2013 06:01:14 +1000 (EST) Received: from /spool/local by e23smtp01.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 28 Jun 2013 05:52:17 +1000 Received: from d23relay04.au.ibm.com (d23relay04.au.ibm.com [9.190.234.120]) by d23dlp02.au.ibm.com (Postfix) with ESMTP id 780852BB0054 for ; Fri, 28 Jun 2013 06:01:11 +1000 (EST) Received: from d23av04.au.ibm.com (d23av04.au.ibm.com [9.190.235.139]) by d23relay04.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r5RJkJFK32047346 for ; Fri, 28 Jun 2013 05:46:19 +1000 Received: from d23av04.au.ibm.com (loopback [127.0.0.1]) by d23av04.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r5RK19RP014057 for ; Fri, 28 Jun 2013 06:01:11 +1000 From: "Srivatsa S. Bhat" Subject: [PATCH v3 31/45] alpha/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 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" Cc: linux-arch@vger.kernel.org, nikunj@linux.vnet.ibm.com, zhong@linux.vnet.ibm.com, linux-pm@vger.kernel.org, fweisbec@gmail.com, linux-alpha@vger.kernel.org, linux-kernel@vger.kernel.org, rostedt@goodmis.org, xiaoguangrong@linux.vnet.ibm.com, sbw@mit.edu, Ivan Kokshaysky , wangyun@linux.vnet.ibm.com, "Srivatsa S. Bhat" , netdev@vger.kernel.org, Matt Turner , linuxppc-dev@lists.ozlabs.org, Thomas Gleixner , Richard Henderson 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 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(); }