From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934461AbaFIWrD (ORCPT ); Mon, 9 Jun 2014 18:47:03 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:57187 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934332AbaFIWqO (ORCPT ); Mon, 9 Jun 2014 18:46:14 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Robert Richter , Will Deacon , Weng Meiling Subject: [PATCH 3.10 39/40] ARM: perf: hook up perf_sample_event_took around pmu irq handling Date: Mon, 9 Jun 2014 15:49:10 -0700 Message-Id: <20140609224840.483198765@linuxfoundation.org> X-Mailer: git-send-email 1.9.0 In-Reply-To: <20140609224839.127615063@linuxfoundation.org> References: <20140609224839.127615063@linuxfoundation.org> User-Agent: quilt/0.63-1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Will Deacon commit 5f5092e72cc25a6a5785308270e0085b2b2772cc upstream. Since we indirect all of our PMU IRQ handling through a dispatcher, it's trivial to hook up perf_sample_event_took to prevent applications such as oprofile from generating interrupt storms due to an unrealisticly low sample period. Reported-by: Robert Richter Signed-off-by: Will Deacon Cc: Weng Meiling Signed-off-by: Greg Kroah-Hartman --- arch/arm/kernel/perf_event.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) --- a/arch/arm/kernel/perf_event.c +++ b/arch/arm/kernel/perf_event.c @@ -303,11 +303,18 @@ static irqreturn_t armpmu_dispatch_irq(i struct arm_pmu *armpmu = (struct arm_pmu *) dev; struct platform_device *plat_device = armpmu->plat_device; struct arm_pmu_platdata *plat = dev_get_platdata(&plat_device->dev); + int ret; + u64 start_clock, finish_clock; + start_clock = sched_clock(); if (plat && plat->handle_irq) - return plat->handle_irq(irq, dev, armpmu->handle_irq); + ret = plat->handle_irq(irq, dev, armpmu->handle_irq); else - return armpmu->handle_irq(irq, dev); + ret = armpmu->handle_irq(irq, dev); + finish_clock = sched_clock(); + + perf_sample_event_took(finish_clock - start_clock); + return ret; } static void