From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752087AbcBVOuA (ORCPT ); Mon, 22 Feb 2016 09:50:00 -0500 Received: from foss.arm.com ([217.140.101.70]:57648 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751747AbcBVOt7 (ORCPT ); Mon, 22 Feb 2016 09:49:59 -0500 Date: Mon, 22 Feb 2016 14:49:54 +0000 From: Mark Rutland To: "Suzuki K. Poulose" Cc: linux-arm-kernel@lists.infradead.org, punit.agrawal@arm.com, arm@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v6 02/12] arm-cci: Group writes to counter Message-ID: <20160222144954.GE3435@leverpostej> References: <1453720877-24962-1-git-send-email-suzuki.poulose@arm.com> <1453720877-24962-3-git-send-email-suzuki.poulose@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1453720877-24962-3-git-send-email-suzuki.poulose@arm.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 25, 2016 at 11:21:07AM +0000, Suzuki K. Poulose wrote: > Add a helper to group the writes to PMU counter, this will be > used to delay setting the event period to pmu::pmu_enable() > > Cc: Mark Rutland > Cc: Punit Agrawal > Signed-off-by: Suzuki K. Poulose > --- > Changes since V5: > - Use the prev_count from event->hw for the counter value, than > using a single value for all the counters. > --- > drivers/bus/arm-cci.c | 15 +++++++++++++++ > 1 file changed, 15 insertions(+) > > diff --git a/drivers/bus/arm-cci.c b/drivers/bus/arm-cci.c > index ee47e6b..936fa9b 100644 > --- a/drivers/bus/arm-cci.c > +++ b/drivers/bus/arm-cci.c > @@ -771,6 +771,21 @@ static void pmu_write_counter(struct perf_event *event, u32 value) > pmu_write_register(cci_pmu, value, idx, CCI_PMU_CNTR); > } > > +static void __maybe_unused > +pmu_write_counters(struct cci_pmu *cci_pmu, unsigned long *mask) > +{ > + int i; > + struct cci_pmu_hw_events *cci_hw = &cci_pmu->hw_events; > + > + for_each_set_bit(i, mask, cci_pmu->num_cntrs) { > + struct perf_event *event = cci_hw->events[i]; > + > + if (WARN_ON(!event)) > + continue; > + pmu_write_counter(event, (u32)local64_read(&event->hw.prev_count)); > + } > +} I think the cast can go here. The truncation will happen implicitly anyway. Mark. > + > static u64 pmu_event_update(struct perf_event *event) > { > struct hw_perf_event *hwc = &event->hw; > -- > 1.7.9.5 >