From patchwork Wed Apr 14 13:44:05 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 12202843 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 831C5C43461 for ; Wed, 14 Apr 2021 13:44:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 78940611EE for ; Wed, 14 Apr 2021 13:44:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351600AbhDNNoq (ORCPT ); Wed, 14 Apr 2021 09:44:46 -0400 Received: from mail.kernel.org ([198.145.29.99]:52294 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1351587AbhDNNop (ORCPT ); Wed, 14 Apr 2021 09:44:45 -0400 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 18C22611F0; Wed, 14 Apr 2021 13:44:24 +0000 (UTC) Received: from 78.163-31-62.static.virginmediabusiness.co.uk ([62.31.163.78] helo=why.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94) (envelope-from ) id 1lWfoc-007RSZ-Cq; Wed, 14 Apr 2021 14:44:22 +0100 From: Marc Zyngier To: kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org Cc: Mark Rutland , Will Deacon , Rich Felker , Yoshinori Sato , Peter Zijlstra , Arnaldo Carvalho de Melo , Christian Borntraeger , Heiko Carstens , nathan@kernel.org, Viresh Kumar , James Morse , Suzuki K Poulose , Alexandru Elisei , kernel-team@android.com Subject: [PATCH 1/5] KVM: arm64: Divorce the perf code from oprofile helpers Date: Wed, 14 Apr 2021 14:44:05 +0100 Message-Id: <20210414134409.1266357-2-maz@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210414134409.1266357-1-maz@kernel.org> References: <20210414134409.1266357-1-maz@kernel.org> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 62.31.163.78 X-SA-Exim-Rcpt-To: kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, mark.rutland@arm.com, will@kernel.org, dalias@libc.org, ysato@users.sourceforge.jp, peterz@infradead.org, acme@kernel.org, borntraeger@de.ibm.com, hca@linux.ibm.com, nathan@kernel.org, viresh.kumar@linaro.org, james.morse@arm.com, suzuki.poulose@arm.com, alexandru.elisei@arm.com, kernel-team@android.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org KVM/arm64 is the sole user of perf_num_counters(), and really could do without it. Stop using the obsolete API by relying on the existing probing code. Signed-off-by: Marc Zyngier Acked-by: Will Deacon --- arch/arm64/kvm/perf.c | 7 +------ arch/arm64/kvm/pmu-emul.c | 2 +- include/kvm/arm_pmu.h | 4 ++++ 3 files changed, 6 insertions(+), 7 deletions(-) diff --git a/arch/arm64/kvm/perf.c b/arch/arm64/kvm/perf.c index 739164324afe..b8b398670ef2 100644 --- a/arch/arm64/kvm/perf.c +++ b/arch/arm64/kvm/perf.c @@ -50,12 +50,7 @@ static struct perf_guest_info_callbacks kvm_guest_cbs = { int kvm_perf_init(void) { - /* - * Check if HW_PERF_EVENTS are supported by checking the number of - * hardware performance counters. This could ensure the presence of - * a physical PMU and CONFIG_PERF_EVENT is selected. - */ - if (IS_ENABLED(CONFIG_ARM_PMU) && perf_num_counters() > 0) + if (kvm_pmu_probe_pmuver() != 0xf) static_branch_enable(&kvm_arm_pmu_available); return perf_register_guest_info_callbacks(&kvm_guest_cbs); diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c index e32c6e139a09..fd167d4f4215 100644 --- a/arch/arm64/kvm/pmu-emul.c +++ b/arch/arm64/kvm/pmu-emul.c @@ -739,7 +739,7 @@ void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data, kvm_pmu_create_perf_event(vcpu, select_idx); } -static int kvm_pmu_probe_pmuver(void) +int kvm_pmu_probe_pmuver(void) { struct perf_event_attr attr = { }; struct perf_event *event; diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h index 6fd3cda608e4..864b9997efb2 100644 --- a/include/kvm/arm_pmu.h +++ b/include/kvm/arm_pmu.h @@ -61,6 +61,7 @@ int kvm_arm_pmu_v3_get_attr(struct kvm_vcpu *vcpu, int kvm_arm_pmu_v3_has_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr); int kvm_arm_pmu_v3_enable(struct kvm_vcpu *vcpu); +int kvm_pmu_probe_pmuver(void); #else struct kvm_pmu { }; @@ -116,6 +117,9 @@ static inline u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1) { return 0; } + +static inline int kvm_pmu_probe_pmuver(void) { return 0xf; } + #endif #endif