From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2E47EC04A6A for ; Tue, 11 Jul 2023 12:09:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231444AbjGKMJ0 (ORCPT ); Tue, 11 Jul 2023 08:09:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45296 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229987AbjGKMJJ (ORCPT ); Tue, 11 Jul 2023 08:09:09 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id C3D781708; Tue, 11 Jul 2023 05:08:59 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id A88E72B; Tue, 11 Jul 2023 05:09:41 -0700 (PDT) Received: from [10.163.47.87] (unknown [10.163.47.87]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 766923F67D; Tue, 11 Jul 2023 05:08:53 -0700 (PDT) Message-ID: <86792ab2-864a-5c27-95c1-54c4057024db@arm.com> Date: Tue, 11 Jul 2023 17:38:51 +0530 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.11.0 Subject: Re: [PATCH 3/4] arm_pmu: Remove unused PERF_PMU_CAP_HETEROGENEOUS_CPUS capability Content-Language: en-US To: James Clark , linux-perf-users@vger.kernel.org, irogers@google.com Cc: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Adrian Hunter , Thomas Gleixner , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Will Deacon , Kan Liang , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org References: <20230710122138.1450930-1-james.clark@arm.com> <20230710122138.1450930-4-james.clark@arm.com> From: Anshuman Khandual In-Reply-To: <20230710122138.1450930-4-james.clark@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 7/10/23 17:51, James Clark wrote: > Since commit bd2756811766 ("perf: Rewrite core context handling") the > relationship between perf_event_context and PMUs has changed so that > the error scenario that PERF_PMU_CAP_HETEROGENEOUS_CPUS originally > silenced no longer exists. > > Remove the capability and associated comment to avoid confusion that it > actually influences any perf core behavior. This change should be a > no-op. > > Signed-off-by: James Clark > --- > drivers/perf/arm_pmu.c | 7 ++----- > 1 file changed, 2 insertions(+), 5 deletions(-) > > diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c > index d8844a9461a2..297906df6628 100644 > --- a/drivers/perf/arm_pmu.c > +++ b/drivers/perf/arm_pmu.c > @@ -872,15 +872,12 @@ struct arm_pmu *armpmu_alloc(void) > .attr_groups = pmu->attr_groups, > /* > * This is a CPU PMU potentially in a heterogeneous > - * configuration (e.g. big.LITTLE). This is not an uncore PMU, > - * and we have taken ctx sharing into account (e.g. with our > - * pmu::filter callback and pmu::event_init group validation). > - * > + * configuration (e.g. big.LITTLE) so > * PERF_PMU_CAP_EXTENDED_HW_TYPE is required to open the legacy > * PERF_TYPE_HARDWARE and PERF_TYPE_HW_CACHE events on a > * specific PMU. > */ > - .capabilities = PERF_PMU_CAP_HETEROGENEOUS_CPUS | PERF_PMU_CAP_EXTENDED_REGS | > + .capabilities = PERF_PMU_CAP_EXTENDED_REGS | > PERF_PMU_CAP_EXTENDED_HW_TYPE, Small nit, the second line could be folded back into the first one. > }; >