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 1A1D3C43217 for ; Mon, 28 Nov 2022 03:06:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229754AbiK1DGZ (ORCPT ); Sun, 27 Nov 2022 22:06:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58646 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229475AbiK1DGX (ORCPT ); Sun, 27 Nov 2022 22:06:23 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 07D8AB7F2; Sun, 27 Nov 2022 19:06:22 -0800 (PST) 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 5E3A4D6E; Sun, 27 Nov 2022 19:06:28 -0800 (PST) Received: from [10.162.40.16] (unknown [10.162.40.16]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 0833E3F73D; Sun, 27 Nov 2022 19:06:18 -0800 (PST) Message-ID: <60767243-2f3e-a7aa-06e1-674e43f18e9c@arm.com> Date: Mon, 28 Nov 2022 08:36:15 +0530 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.2.2 Subject: Re: [PATCH] arm64/perf: Replace PMU version number '0' with ID_AA64DFR0_EL1_PMUVer_NI To: linux-arm-kernel@lists.infradead.org, will@kernel.org, Marc Zyngier Cc: Arnaldo Carvalho de Melo , Mark Rutland , Catalin Marinas , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org References: <20221128025449.39085-1-anshuman.khandual@arm.com> Content-Language: en-US From: Anshuman Khandual In-Reply-To: <20221128025449.39085-1-anshuman.khandual@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 11/28/22 08:24, Anshuman Khandual wrote: > __armv8pmu_probe_pmu() returns if detected PMU is either not implemented or > implementation defined. Extracted ID_AA64DFR0_EL1_PMUVer value, when PMU is > not implemented is '0' which can be replaced with ID_AA64DFR0_EL1_PMUVer_NI > defined as '0b0000'. > > Cc: Arnaldo Carvalho de Melo > Cc: Mark Rutland > Cc: Will Deacon > Cc: Catalin Marinas > Cc: linux-perf-users@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Cc: linux-arm-kernel@lists.infradead.org > Signed-off-by: Anshuman Khandual > --- > This applies on v6.1-rc6 > > arch/arm64/kernel/perf_event.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c > index 85a3aaefc0fb..b638f584b4dd 100644 > --- a/arch/arm64/kernel/perf_event.c > +++ b/arch/arm64/kernel/perf_event.c > @@ -1188,7 +1188,8 @@ static void __armv8pmu_probe_pmu(void *info) > dfr0 = read_sysreg(id_aa64dfr0_el1); > pmuver = cpuid_feature_extract_unsigned_field(dfr0, > ID_AA64DFR0_EL1_PMUVer_SHIFT); > - if (pmuver == ID_AA64DFR0_EL1_PMUVer_IMP_DEF || pmuver == 0) > + if (pmuver == ID_AA64DFR0_EL1_PMUVer_IMP_DEF || > + pmuver == ID_AA64DFR0_EL1_PMUVer_NI) > return; > > cpu_pmu->pmuver = pmuver; > -- + Marc Zyngier There are some KVM related pmuver not-implemented check as well, should they be replaced in this patch or rather in a separate patch ? arch/arm64/kvm/pmu-emul.c: if (pmu->pmuver == 0 || pmu->pmuver == ID_AA64DFR0_EL1_PMUVer_IMP_DEF) arch/arm64/kvm/pmu-emul.c: if (pmu->pmuver == 0 || arch/arm64/kvm/pmu-emul.c: pmu->pmuver == ID_AA64DFR0_EL1_PMUVer_IMP_DEF) - Anshuman