From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030904AbcGKRDv (ORCPT ); Mon, 11 Jul 2016 13:03:51 -0400 Received: from mx1.redhat.com ([209.132.183.28]:50527 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030774AbcGKRDu (ORCPT ); Mon, 11 Jul 2016 13:03:50 -0400 Subject: Re: [PATCH 3/3] time: drop local_irq_save/restore from irqtime_account_irq To: riel@redhat.com, linux-kernel@vger.kernel.org References: <1468256037-6307-1-git-send-email-riel@redhat.com> <1468256037-6307-4-git-send-email-riel@redhat.com> Cc: peterz@infradead.org, mingo@kernel.org, fweisbec@redhat.com, wanpeng.li@hotmail.com, efault@gmx.de, tglx@linutronix.de, rkrcmar@redhat.com From: Paolo Bonzini Message-ID: Date: Mon, 11 Jul 2016 19:03:39 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.1.1 MIME-Version: 1.0 In-Reply-To: <1468256037-6307-4-git-send-email-riel@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Mon, 11 Jul 2016 17:03:45 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/07/2016 18:53, riel@redhat.com wrote: > From: Rik van Riel > > Paolo pointed out that irqs are already blocked when irqtime_account_irq > is called. That means there is no reason to call local_irq_save/restore > again. > > Signed-off-by: Rik van Riel > Suggested-by: Paolo Bonzini > --- > kernel/sched/cputime.c | 4 ---- > 1 file changed, 4 deletions(-) > > diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c > index ca7e33cb0967..7b6fa4d7ad4c 100644 > --- a/kernel/sched/cputime.c > +++ b/kernel/sched/cputime.c > @@ -49,15 +49,12 @@ DEFINE_PER_CPU(seqcount_t, irq_time_seq); > */ > void irqtime_account_irq(struct task_struct *curr) > { > - unsigned long flags; > s64 delta; > int cpu; > > if (!sched_clock_irqtime) > return; > > - local_irq_save(flags); > - > cpu = smp_processor_id(); > delta = sched_clock_cpu(cpu) - __this_cpu_read(irq_start_time); > __this_cpu_add(irq_start_time, delta); > @@ -75,7 +72,6 @@ void irqtime_account_irq(struct task_struct *curr) > __this_cpu_add(cpu_softirq_time, delta); > > irq_time_write_end(); > - local_irq_restore(flags); > } > EXPORT_SYMBOL_GPL(irqtime_account_irq); > > Reviewed-by: Paolo Bonzini