From patchwork Tue Jan 22 10:49:56 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Murray X-Patchwork-Id: 10775349 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 456B9746 for ; Tue, 22 Jan 2019 10:50:45 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2F6852A510 for ; Tue, 22 Jan 2019 10:50:45 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 22EB72A5BC; Tue, 22 Jan 2019 10:50:45 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 558DF2A510 for ; Tue, 22 Jan 2019 10:50:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=uK8r1TVEWKLL28sUsPKZ2bcV+ZGDjbN9Xbx0GPSv5+A=; b=RIadkzjFiWt0j7P06cQw1RFfJY zN//A+U1ZBYfwmsjsbbIi12A6ZCuPxtPTfcvMNy0pPr5NC6mQsPxE+QMohxpeImh6n2ms1Etoh7Ph 1nPNVU4vKb6I6uQqLVHNJKujKZliMlO287J0zQrvFeq+HdohSefzd9xslzr80rgmBfmm2Sf+qJW3q 38npwoJ4ylq+X86nSsjCEh+gnansysL1i3njYh8BX/M4L7W2AAyNs5ksWf8fhzQYDHxVmQq2QwQ1/ Ap1/SiN+9I4wXqcvhGnKR8HKv01MSbJQSbPUPsqtQ7gQoZZj9c8yeMa+6ngsq9sxTGTv9aBbsxIgB youJvs/A==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gltdh-0002Ca-Ja; Tue, 22 Jan 2019 10:50:41 +0000 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70] helo=foss.arm.com) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gltd9-0001aN-VK for linux-arm-kernel@lists.infradead.org; Tue, 22 Jan 2019 10:50:09 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 70FCAA78; Tue, 22 Jan 2019 02:50:07 -0800 (PST) Received: from e119886-lin.cambridge.arm.com (unknown [10.37.6.11]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 126A93F6A8; Tue, 22 Jan 2019 02:50:05 -0800 (PST) From: Andrew Murray To: Christoffer Dall , Marc Zyngier Subject: [PATCH 3/4] KVM: arm/arm64: lazily create perf events on enable Date: Tue, 22 Jan 2019 10:49:56 +0000 Message-Id: <1548154197-5470-4-git-send-email-andrew.murray@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1548154197-5470-1-git-send-email-andrew.murray@arm.com> References: <1548154197-5470-1-git-send-email-andrew.murray@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190122_025008_019427_5A93910D X-CRM114-Status: GOOD ( 17.91 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, suzuki.poulose@arm.com MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP To prevent re-creating perf events everytime the counter registers are changed, let's instead lazily create the event when the event is first enabled and destroy it when it changes. Signed-off-by: Andrew Murray --- virt/kvm/arm/pmu.c | 114 ++++++++++++++++++++++++++++++++++++----------------- 1 file changed, 78 insertions(+), 36 deletions(-) diff --git a/virt/kvm/arm/pmu.c b/virt/kvm/arm/pmu.c index 4464899..1921ca9 100644 --- a/virt/kvm/arm/pmu.c +++ b/virt/kvm/arm/pmu.c @@ -24,8 +24,11 @@ #include #include -static void kvm_pmu_create_perf_event(struct kvm_vcpu *vcpu, u64 data, - u64 select_idx); +static void kvm_pmu_reenable_enabled_single(struct kvm_vcpu *vcpu, u64 pair); +static void kvm_pmu_counter_create_enabled_perf_event(struct kvm_vcpu *vcpu, + u64 select_idx); +static void kvm_pmu_stop_counter(struct kvm_vcpu *vcpu, struct kvm_pmc *pmc); + /** * kvm_pmu_get_counter_value - get PMU counter value * @vcpu: The vcpu pointer @@ -59,18 +62,16 @@ u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu, u64 select_idx) */ void kvm_pmu_set_counter_value(struct kvm_vcpu *vcpu, u64 select_idx, u64 val) { - u64 reg, data; + u64 reg; + struct kvm_pmu *pmu = &vcpu->arch.pmu; + struct kvm_pmc *pmc = &pmu->pmc[select_idx]; reg = (select_idx == ARMV8_PMU_CYCLE_IDX) ? PMCCNTR_EL0 : PMEVCNTR0_EL0 + select_idx; __vcpu_sys_reg(vcpu, reg) += (s64)val - kvm_pmu_get_counter_value(vcpu, select_idx); - reg = (select_idx == ARMV8_PMU_CYCLE_IDX) - ? PMCCFILTR_EL0 : PMEVTYPER0_EL0 + select_idx; - data = __vcpu_sys_reg(vcpu, reg + select_idx); - - /* Recreate the perf event to reflect the updated sample_period */ - kvm_pmu_create_perf_event(vcpu, data, select_idx); + kvm_pmu_stop_counter(vcpu, pmc); + kvm_pmu_reenable_enabled_single(vcpu, select_idx); } /** @@ -88,6 +89,7 @@ static void kvm_pmu_release_perf_event(struct kvm_pmc *pmc) /** * kvm_pmu_stop_counter - stop PMU counter + * @vcpu: The vcpu pointer * @pmc: The PMU counter pointer * * If this counter has been configured to monitor some event, release it here. @@ -150,6 +152,25 @@ u64 kvm_pmu_valid_counter_mask(struct kvm_vcpu *vcpu) } /** + * kvm_pmu_enable_counter_single - create/enable a unpaired counter + * @vcpu: The vcpu pointer + * @select_idx: The counter index + */ +static void kvm_pmu_enable_counter_single(struct kvm_vcpu *vcpu, u64 select_idx) +{ + struct kvm_pmu *pmu = &vcpu->arch.pmu; + struct kvm_pmc *pmc = &pmu->pmc[select_idx]; + + if (!pmc->perf_event) { + kvm_pmu_counter_create_enabled_perf_event(vcpu, select_idx); + } else if (pmc->perf_event) { + perf_event_enable(pmc->perf_event); + if (pmc->perf_event->state != PERF_EVENT_STATE_ACTIVE) + kvm_debug("fail to enable perf event\n"); + } +} + +/** * kvm_pmu_enable_counter - enable selected PMU counter * @vcpu: The vcpu pointer * @val: the value guest writes to PMCNTENSET register @@ -159,8 +180,6 @@ u64 kvm_pmu_valid_counter_mask(struct kvm_vcpu *vcpu) void kvm_pmu_enable_counter(struct kvm_vcpu *vcpu, u64 val) { int i; - struct kvm_pmu *pmu = &vcpu->arch.pmu; - struct kvm_pmc *pmc; if (!(__vcpu_sys_reg(vcpu, PMCR_EL0) & ARMV8_PMU_PMCR_E) || !val) return; @@ -169,16 +188,44 @@ void kvm_pmu_enable_counter(struct kvm_vcpu *vcpu, u64 val) if (!(val & BIT(i))) continue; - pmc = &pmu->pmc[i]; - if (pmc->perf_event) { - perf_event_enable(pmc->perf_event); - if (pmc->perf_event->state != PERF_EVENT_STATE_ACTIVE) - kvm_debug("fail to enable perf event\n"); - } + kvm_pmu_enable_counter_single(vcpu, i); } } /** + * kvm_pmu_reenable_enabled_single - reenable a counter if it should be enabled + * @vcpu: The vcpu pointer + * @select_idx: The counter index + */ +static void kvm_pmu_reenable_enabled_single(struct kvm_vcpu *vcpu, + u64 select_idx) +{ + u64 mask = kvm_pmu_valid_counter_mask(vcpu); + u64 set = __vcpu_sys_reg(vcpu, PMCNTENSET_EL0) & mask; + + if (!(__vcpu_sys_reg(vcpu, PMCR_EL0) & ARMV8_PMU_PMCR_E)) + return; + + if (set & BIT(select_idx)) + kvm_pmu_enable_counter_single(vcpu, select_idx); +} + +/** + * kvm_pmu_disable_counter - disable selected PMU counter + * @vcpu: The vcpu pointer + * @pmc: The counter to dissable + */ +static void kvm_pmu_disable_counter_single(struct kvm_vcpu *vcpu, + u64 select_idx) +{ + struct kvm_pmu *pmu = &vcpu->arch.pmu; + struct kvm_pmc *pmc = &pmu->pmc[select_idx]; + + if (pmc->perf_event) + perf_event_disable(pmc->perf_event); +} + +/** * kvm_pmu_disable_counter - disable selected PMU counter * @vcpu: The vcpu pointer * @val: the value guest writes to PMCNTENCLR register @@ -188,8 +235,6 @@ void kvm_pmu_enable_counter(struct kvm_vcpu *vcpu, u64 val) void kvm_pmu_disable_counter(struct kvm_vcpu *vcpu, u64 val) { int i; - struct kvm_pmu *pmu = &vcpu->arch.pmu; - struct kvm_pmc *pmc; if (!val) return; @@ -198,9 +243,7 @@ void kvm_pmu_disable_counter(struct kvm_vcpu *vcpu, u64 val) if (!(val & BIT(i))) continue; - pmc = &pmu->pmc[i]; - if (pmc->perf_event) - perf_event_disable(pmc->perf_event); + kvm_pmu_disable_counter_single(vcpu, i); } } @@ -382,28 +425,22 @@ void kvm_pmu_handle_pmcr(struct kvm_vcpu *vcpu, u64 val) } } -static bool kvm_pmu_counter_is_enabled(struct kvm_vcpu *vcpu, u64 select_idx) -{ - return (__vcpu_sys_reg(vcpu, PMCR_EL0) & ARMV8_PMU_PMCR_E) && - (__vcpu_sys_reg(vcpu, PMCNTENSET_EL0) & BIT(select_idx)); -} - /** - * kvm_pmu_create_perf_event - create a perf event for a counter + * kvm_pmu_counter_create_enabled_perf_event - create a perf event for a counter * @vcpu: The vcpu pointer - * @data: Type of event as per PMXEVTYPER_EL0 format * @select_idx: The number of selected counter */ -static void kvm_pmu_create_perf_event(struct kvm_vcpu *vcpu, u64 data, - u64 select_idx) +static void kvm_pmu_counter_create_enabled_perf_event(struct kvm_vcpu *vcpu, + u64 select_idx) { struct kvm_pmu *pmu = &vcpu->arch.pmu; struct kvm_pmc *pmc = &pmu->pmc[select_idx]; struct perf_event *event; struct perf_event_attr attr; - u64 eventsel, counter; + u64 eventsel, counter, data; + + data = __vcpu_sys_reg(vcpu, PMEVTYPER0_EL0 + select_idx); - kvm_pmu_stop_counter(vcpu, pmc); eventsel = data & ARMV8_PMU_EVTYPE_EVENT; /* Software increment event does't need to be backed by a perf event */ @@ -415,7 +452,6 @@ static void kvm_pmu_create_perf_event(struct kvm_vcpu *vcpu, u64 data, attr.type = PERF_TYPE_RAW; attr.size = sizeof(attr); attr.pinned = 1; - attr.disabled = !kvm_pmu_counter_is_enabled(vcpu, select_idx); attr.exclude_user = data & ARMV8_PMU_EXCLUDE_EL0 ? 1 : 0; attr.exclude_kernel = data & ARMV8_PMU_EXCLUDE_EL1 ? 1 : 0; attr.exclude_hv = 1; /* Don't count EL2 events */ @@ -451,7 +487,13 @@ static void kvm_pmu_create_perf_event(struct kvm_vcpu *vcpu, u64 data, void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data, u64 select_idx) { - kvm_pmu_create_perf_event(vcpu, data, select_idx); + struct kvm_pmu *pmu = &vcpu->arch.pmu; + struct kvm_pmc *pmc = &pmu->pmc[select_idx]; + u64 event_type = data & ARMV8_PMU_EVTYPE_MASK; + + kvm_pmu_stop_counter(vcpu, pmc); + __vcpu_sys_reg(vcpu, PMEVTYPER0_EL0 + select_idx) = event_type; + kvm_pmu_reenable_enabled_single(vcpu, select_idx); } bool kvm_arm_support_pmu_v3(void)