From patchwork Fri Mar 8 12:07:39 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Murray X-Patchwork-Id: 10844571 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 459A81390 for ; Fri, 8 Mar 2019 12:08:30 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 29C012E192 for ; Fri, 8 Mar 2019 12:08:30 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 1E25C2E2AF; Fri, 8 Mar 2019 12:08:30 +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 C90C32E192 for ; Fri, 8 Mar 2019 12:08:29 +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:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version: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=JafHBkG146QwqWMfbUqDlVywkd0Lmnr/j8D+04L5PvY=; b=tXiwDuNWQ57c/X AGNy2Wvx2WlcxZvSK1/kGDIQx28NxGUnNB7ELYdN2c3j5gCO/DUTG8ym0yIEq3hqobzdjyWmiVYlR ega2XqakRGhlQcB+9gDafhcuWg5faEaU4i9PVTwjJ2my3sPnheuTK1XYqnDZswAwxRVJQN+OKPXd2 xp8Pl0yjs+U/POgEaGUmnuYqXZ3fQFgel2zEf2QjbFo+iUggxR6NyS+V9Lja6xuYSxaATLQaQvmVN qSrO3RP3PO+FziyTxZL0VKdjhzb6Q03KsXk5qGJodZvlOrPmddaP/ShPhEGYKt3fs3cz7SxnuuNa8 ZJWR1MGBIfdcE92E5Olw==; 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 1h2EIY-0007fk-AT; Fri, 08 Mar 2019 12:08:22 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h2EI8-0007BK-Ha for linux-arm-kernel@lists.infradead.org; Fri, 08 Mar 2019 12:08:03 +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 D6761EBD; Fri, 8 Mar 2019 04:07:55 -0800 (PST) Received: from e119886-lin.cambridge.arm.com (unknown [10.37.6.16]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E48653F706; Fri, 8 Mar 2019 04:07:53 -0800 (PST) From: Andrew Murray To: Christoffer Dall , Marc Zyngier , Catalin Marinas , Will Deacon , Mark Rutland Subject: [PATCH v11 1/8] arm64: arm_pmu: remove unnecessary isb instruction Date: Fri, 8 Mar 2019 12:07:39 +0000 Message-Id: <20190308120746.56897-2-andrew.murray@arm.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190308120746.56897-1-andrew.murray@arm.com> References: <20190308120746.56897-1-andrew.murray@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190308_040756_814442_DB8A41FA X-CRM114-Status: GOOD ( 10.24 ) 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: Julien Thierry , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, Suzuki K Poulose 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 The armv8pmu_enable_event_counter function issues an isb instruction after enabling a pair of counters - this doesn't provide any value and is inconsistent with the armv8pmu_disable_event_counter. In any case armv8pmu_enable_event_counter is always called with the PMU stopped. Starting the PMU with armv8pmu_start results in an isb instruction being issued prior to writing to PMCR_EL0. Let's remove the unnecessary isb instruction. Signed-off-by: Andrew Murray Reviewed-by: Suzuki K Poulose Acked-by: Mark Rutland --- arch/arm64/kernel/perf_event.c | 1 - 1 file changed, 1 deletion(-) diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c index 1620a371b1f5..1c717965b3ff 100644 --- a/arch/arm64/kernel/perf_event.c +++ b/arch/arm64/kernel/perf_event.c @@ -533,7 +533,6 @@ static inline void armv8pmu_enable_event_counter(struct perf_event *event) armv8pmu_enable_counter(idx); if (armv8pmu_event_is_chained(event)) armv8pmu_enable_counter(idx - 1); - isb(); } static inline int armv8pmu_disable_counter(int idx) From patchwork Fri Mar 8 12:07:40 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Murray X-Patchwork-Id: 10844573 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 BE276139A for ; Fri, 8 Mar 2019 12:08:38 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A1BD62E192 for ; Fri, 8 Mar 2019 12:08:38 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 924DF2E2AF; Fri, 8 Mar 2019 12:08:38 +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 041692E192 for ; Fri, 8 Mar 2019 12:08:38 +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:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version: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=my6r5cOet72N7dJY5u9Q/9LRlxgmEXSklGlWwbpCNvc=; b=rj9QWvdUzTi/Uw aqFcKBtzbcwEjQLFjbWVsqz4txJem0ryyYxE2ugbD/s4f2UNb44KyZyZoPYZNN7s3EGjDQ3wJGfbu m8/gGTbUEfpdNdicK97MAoddWXYOL0Z6x6B4BGpKnc8quHG8fnJW84uYst3zyXD69hrjwi5/6i+ji 2J2622zjtg/ZvkDKYT4jhr6DRBZafEOsGgUH1HX1Sj4yxd5i7x+4CliT5e/Gdhzjs2hBK4pkLFeku nj9Mn6h6bXtIziauIFxnMNQCIQBzlc6TGVNKlAzrYKukH/tnh5A9AiXp5/awj1SBA02BkoY+SfPxD +Ki+MXVRSOGQYze72N0Q==; 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 1h2EIk-0007v8-Of; Fri, 08 Mar 2019 12:08:34 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h2EIB-0007Fj-Sw for linux-arm-kernel@lists.infradead.org; Fri, 08 Mar 2019 12:08:07 +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 4742F1596; Fri, 8 Mar 2019 04:07:58 -0800 (PST) Received: from e119886-lin.cambridge.arm.com (unknown [10.37.6.16]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 2D2AE3F706; Fri, 8 Mar 2019 04:07:56 -0800 (PST) From: Andrew Murray To: Christoffer Dall , Marc Zyngier , Catalin Marinas , Will Deacon , Mark Rutland Subject: [PATCH v11 2/8] arm64: KVM: encapsulate kvm_cpu_context in kvm_host_data Date: Fri, 8 Mar 2019 12:07:40 +0000 Message-Id: <20190308120746.56897-3-andrew.murray@arm.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190308120746.56897-1-andrew.murray@arm.com> References: <20190308120746.56897-1-andrew.murray@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190308_040800_740336_87FA698B X-CRM114-Status: GOOD ( 13.80 ) 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: Julien Thierry , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, Suzuki K Poulose 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 The virt/arm core allocates a kvm_cpu_context_t percpu, at present this is a typedef to kvm_cpu_context and is used to store host cpu context. The kvm_cpu_context structure is also used elsewhere to hold vcpu context. In order to use the percpu to hold additional future host information we encapsulate kvm_cpu_context in a new structure and rename the typedef and percpu to match. Signed-off-by: Andrew Murray --- arch/arm/include/asm/kvm_host.h | 8 ++++++-- arch/arm64/include/asm/kvm_asm.h | 3 ++- arch/arm64/include/asm/kvm_host.h | 14 +++++++++----- arch/arm64/kernel/asm-offsets.c | 1 + virt/kvm/arm/arm.c | 12 +++++++----- 5 files changed, 25 insertions(+), 13 deletions(-) diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 50e89869178a..a358cb15bb0d 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -146,7 +146,11 @@ struct kvm_cpu_context { u32 cp15[NR_CP15_REGS]; }; -typedef struct kvm_cpu_context kvm_cpu_context_t; +struct kvm_host_data { + struct kvm_cpu_context host_ctxt; +}; + +typedef struct kvm_host_data kvm_host_data_t; struct vcpu_reset_state { unsigned long pc; @@ -171,7 +175,7 @@ struct kvm_vcpu_arch { struct kvm_vcpu_fault_info fault; /* Host FP context */ - kvm_cpu_context_t *host_cpu_context; + struct kvm_cpu_context *host_cpu_context; /* VGIC state */ struct vgic_cpu vgic_cpu; diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h index f5b79e995f40..ff73f5462aca 100644 --- a/arch/arm64/include/asm/kvm_asm.h +++ b/arch/arm64/include/asm/kvm_asm.h @@ -108,7 +108,8 @@ extern u32 __kvm_get_mdcr_el2(void); .endm .macro get_host_ctxt reg, tmp - hyp_adr_this_cpu \reg, kvm_host_cpu_state, \tmp + hyp_adr_this_cpu \reg, kvm_host_data, \tmp + add \reg, \reg, #HOST_DATA_CONTEXT .endm .macro get_vcpu_ptr vcpu, ctxt diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index da3fc7324d68..1d36619d6650 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -207,7 +207,11 @@ struct kvm_cpu_context { struct kvm_vcpu *__hyp_running_vcpu; }; -typedef struct kvm_cpu_context kvm_cpu_context_t; +struct kvm_host_data { + struct kvm_cpu_context host_ctxt; +}; + +typedef struct kvm_host_data kvm_host_data_t; struct vcpu_reset_state { unsigned long pc; @@ -250,7 +254,7 @@ struct kvm_vcpu_arch { struct kvm_guest_debug_arch external_debug_state; /* Pointer to host CPU context */ - kvm_cpu_context_t *host_cpu_context; + struct kvm_cpu_context *host_cpu_context; struct thread_info *host_thread_info; /* hyp VA */ struct user_fpsimd_state *host_fpsimd_state; /* hyp VA */ @@ -398,7 +402,7 @@ void kvm_set_sei_esr(struct kvm_vcpu *vcpu, u64 syndrome); struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr); -DECLARE_PER_CPU(kvm_cpu_context_t, kvm_host_cpu_state); +DECLARE_PER_CPU(kvm_host_data_t, kvm_host_data); void __kvm_enable_ssbs(void); @@ -411,8 +415,8 @@ static inline void __cpu_init_hyp_mode(phys_addr_t pgd_ptr, * kernel's mapping to the linear mapping, and store it in tpidr_el2 * so that we can use adr_l to access per-cpu variables in EL2. */ - u64 tpidr_el2 = ((u64)this_cpu_ptr(&kvm_host_cpu_state) - - (u64)kvm_ksym_ref(kvm_host_cpu_state)); + u64 tpidr_el2 = ((u64)this_cpu_ptr(&kvm_host_data) - + (u64)kvm_ksym_ref(kvm_host_data)); /* * Call initialization code, and switch to the full blown HYP code. diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c index 65b8afc84466..9b03554ba5d2 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -146,6 +146,7 @@ int main(void) DEFINE(VCPU_FPEXC32_EL2, offsetof(struct kvm_vcpu, arch.ctxt.sys_regs[FPEXC32_EL2])); DEFINE(VCPU_HOST_CONTEXT, offsetof(struct kvm_vcpu, arch.host_cpu_context)); DEFINE(HOST_CONTEXT_VCPU, offsetof(struct kvm_cpu_context, __hyp_running_vcpu)); + DEFINE(HOST_DATA_CONTEXT, offsetof(struct kvm_host_data, host_ctxt)); #endif #ifdef CONFIG_CPU_PM DEFINE(CPU_SUSPEND_SZ, sizeof(struct cpu_suspend_ctx)); diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c index 9c486fad3f9f..6958b98b8d52 100644 --- a/virt/kvm/arm/arm.c +++ b/virt/kvm/arm/arm.c @@ -56,7 +56,7 @@ __asm__(".arch_extension virt"); #endif -DEFINE_PER_CPU(kvm_cpu_context_t, kvm_host_cpu_state); +DEFINE_PER_CPU(kvm_host_data_t, kvm_host_data); static DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page); /* Per-CPU variable containing the currently running vcpu. */ @@ -363,8 +363,10 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) { int *last_ran; + kvm_host_data_t *cpu_data; last_ran = this_cpu_ptr(vcpu->kvm->arch.last_vcpu_ran); + cpu_data = this_cpu_ptr(&kvm_host_data); /* * We might get preempted before the vCPU actually runs, but @@ -376,7 +378,7 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) } vcpu->cpu = cpu; - vcpu->arch.host_cpu_context = this_cpu_ptr(&kvm_host_cpu_state); + vcpu->arch.host_cpu_context = &cpu_data->host_ctxt; kvm_arm_set_running_vcpu(vcpu); kvm_vgic_load(vcpu); @@ -1568,10 +1570,10 @@ static int init_hyp_mode(void) } for_each_possible_cpu(cpu) { - kvm_cpu_context_t *cpu_ctxt; + kvm_host_data_t *cpu_data; - cpu_ctxt = per_cpu_ptr(&kvm_host_cpu_state, cpu); - err = create_hyp_mappings(cpu_ctxt, cpu_ctxt + 1, PAGE_HYP); + cpu_data = per_cpu_ptr(&kvm_host_data, cpu); + err = create_hyp_mappings(cpu_data, cpu_data + 1, PAGE_HYP); if (err) { kvm_err("Cannot map host CPU state: %d\n", err); From patchwork Fri Mar 8 12:07:41 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Murray X-Patchwork-Id: 10844575 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 9DBF71390 for ; 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Fri, 8 Mar 2019 04:07:58 -0800 (PST) From: Andrew Murray To: Christoffer Dall , Marc Zyngier , Catalin Marinas , Will Deacon , Mark Rutland Subject: [PATCH v11 3/8] arm64: KVM: add accessors to track guest/host only counters Date: Fri, 8 Mar 2019 12:07:41 +0000 Message-Id: <20190308120746.56897-4-andrew.murray@arm.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190308120746.56897-1-andrew.murray@arm.com> References: <20190308120746.56897-1-andrew.murray@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190308_040801_394674_3F5666E8 X-CRM114-Status: GOOD ( 16.22 ) 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: Julien Thierry , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, Suzuki K Poulose 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 In order to effeciently switch events_{guest,host} perf counters at guest entry/exit we add bitfields to kvm_cpu_context for guest and host events as well as accessors for updating them. A function is also provided which allows the PMU driver to determine if a counter should start counting when it is enabled. With exclude_host, events on !VHE we may only start counting when entering the guest. Signed-off-by: Andrew Murray --- arch/arm64/include/asm/kvm_host.h | 17 +++++++++++ arch/arm64/kvm/Makefile | 2 +- arch/arm64/kvm/pmu.c | 49 +++++++++++++++++++++++++++++++ 3 files changed, 67 insertions(+), 1 deletion(-) create mode 100644 arch/arm64/kvm/pmu.c diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 1d36619d6650..4b7219128f2d 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -207,8 +207,14 @@ struct kvm_cpu_context { struct kvm_vcpu *__hyp_running_vcpu; }; +struct kvm_pmu_events { + u32 events_host; + u32 events_guest; +}; + struct kvm_host_data { struct kvm_cpu_context host_ctxt; + struct kvm_pmu_events pmu_events; }; typedef struct kvm_host_data kvm_host_data_t; @@ -479,11 +485,22 @@ void kvm_arch_vcpu_load_fp(struct kvm_vcpu *vcpu); void kvm_arch_vcpu_ctxsync_fp(struct kvm_vcpu *vcpu); void kvm_arch_vcpu_put_fp(struct kvm_vcpu *vcpu); +static inline bool kvm_pmu_counter_defered(struct perf_event_attr *attr) +{ + return attr->exclude_host; +} + #ifdef CONFIG_KVM /* Avoid conflicts with core headers if CONFIG_KVM=n */ static inline int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu) { return kvm_arch_vcpu_run_map_fp(vcpu); } + +void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr); +void kvm_clr_pmu_events(u32 clr); +#else +static inline void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr) {} +static inline void kvm_clr_pmu_events(u32 clr) {} #endif static inline void kvm_arm_vhe_guest_enter(void) diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index 0f2a135ba15b..f34cb49b66ae 100644 --- a/arch/arm64/kvm/Makefile +++ b/arch/arm64/kvm/Makefile @@ -19,7 +19,7 @@ kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/psci.o $(KVM)/arm/perf.o kvm-$(CONFIG_KVM_ARM_HOST) += inject_fault.o regmap.o va_layout.o kvm-$(CONFIG_KVM_ARM_HOST) += hyp.o hyp-init.o handle_exit.o kvm-$(CONFIG_KVM_ARM_HOST) += guest.o debug.o reset.o sys_regs.o sys_regs_generic_v8.o -kvm-$(CONFIG_KVM_ARM_HOST) += vgic-sys-reg-v3.o fpsimd.o +kvm-$(CONFIG_KVM_ARM_HOST) += vgic-sys-reg-v3.o fpsimd.o pmu.o kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/aarch32.o kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic/vgic.o diff --git a/arch/arm64/kvm/pmu.c b/arch/arm64/kvm/pmu.c new file mode 100644 index 000000000000..43965a3cc0f4 --- /dev/null +++ b/arch/arm64/kvm/pmu.c @@ -0,0 +1,49 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * arch/arm64/kvm/pmu.c: Switching between guest and host counters + * + * Copyright 2019 Arm Limited + * Author: Andrew Murray + */ +#include +#include + +DECLARE_PER_CPU(kvm_host_data_t, kvm_host_data); + +/* + * Given the exclude_{host,guest} attributes, determine if we are going + * to need to switch counters at guest entry/exit. + */ +static bool kvm_pmu_switch_needed(struct perf_event_attr *attr) +{ + /* Only switch if attributes are different */ + return (attr->exclude_host ^ attr->exclude_guest); +} + +/* + * Add events to track that we may want to switch at guest entry/exit + * time. + */ +void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr) +{ + struct kvm_host_data *ctx = this_cpu_ptr(&kvm_host_data); + + if (!kvm_pmu_switch_needed(attr)) + return; + + if (!attr->exclude_host) + ctx->pmu_events.events_host |= set; + if (!attr->exclude_guest) + ctx->pmu_events.events_guest |= set; +} + +/* + * Stop tracking events + */ +void kvm_clr_pmu_events(u32 clr) +{ + struct kvm_host_data *ctx = this_cpu_ptr(&kvm_host_data); + + ctx->pmu_events.events_host &= ~clr; + ctx->pmu_events.events_guest &= ~clr; +} From patchwork Fri Mar 8 12:07:42 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Murray X-Patchwork-Id: 10844583 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 297C81390 for ; 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Fri, 8 Mar 2019 04:08:00 -0800 (PST) From: Andrew Murray To: Christoffer Dall , Marc Zyngier , Catalin Marinas , Will Deacon , Mark Rutland Subject: [PATCH v11 4/8] arm64: arm_pmu: Add !VHE support for exclude_host/exclude_guest attributes Date: Fri, 8 Mar 2019 12:07:42 +0000 Message-Id: <20190308120746.56897-5-andrew.murray@arm.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190308120746.56897-1-andrew.murray@arm.com> References: <20190308120746.56897-1-andrew.murray@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190308_040803_930064_C96E72D9 X-CRM114-Status: GOOD ( 16.18 ) 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: Julien Thierry , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, Suzuki K Poulose 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 Add support for the :G and :H attributes in perf by handling the exclude_host/exclude_guest event attributes. We notify KVM of counters that we wish to be enabled or disabled on guest entry/exit and thus defer from starting or stopping events based on their event attributes. With !VHE we switch the counters between host/guest at EL2. We are able to eliminate counters counting host events on the boundaries of guest entry/exit when using :G by filtering out EL2 for exclude_host. When using !exclude_hv there is a small blackout window at the guest entry/exit where host events are not captured. Signed-off-by: Andrew Murray --- arch/arm64/kernel/perf_event.c | 43 ++++++++++++++++++++++++++++------ 1 file changed, 36 insertions(+), 7 deletions(-) diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c index 1c717965b3ff..64f02a9fd7cd 100644 --- a/arch/arm64/kernel/perf_event.c +++ b/arch/arm64/kernel/perf_event.c @@ -26,6 +26,7 @@ #include #include +#include #include #include #include @@ -528,11 +529,21 @@ static inline int armv8pmu_enable_counter(int idx) static inline void armv8pmu_enable_event_counter(struct perf_event *event) { + struct perf_event_attr *attr = &event->attr; int idx = event->hw.idx; + u32 counter_bits = BIT(ARMV8_IDX_TO_COUNTER(idx)); - armv8pmu_enable_counter(idx); if (armv8pmu_event_is_chained(event)) - armv8pmu_enable_counter(idx - 1); + counter_bits |= BIT(ARMV8_IDX_TO_COUNTER(idx - 1)); + + kvm_set_pmu_events(counter_bits, attr); + + /* We rely on the hypervisor switch code to enable guest counters */ + if (!kvm_pmu_counter_defered(attr)) { + armv8pmu_enable_counter(idx); + if (armv8pmu_event_is_chained(event)) + armv8pmu_enable_counter(idx - 1); + } } static inline int armv8pmu_disable_counter(int idx) @@ -545,11 +556,21 @@ static inline int armv8pmu_disable_counter(int idx) static inline void armv8pmu_disable_event_counter(struct perf_event *event) { struct hw_perf_event *hwc = &event->hw; + struct perf_event_attr *attr = &event->attr; int idx = hwc->idx; + u32 counter_bits = BIT(ARMV8_IDX_TO_COUNTER(idx)); if (armv8pmu_event_is_chained(event)) - armv8pmu_disable_counter(idx - 1); - armv8pmu_disable_counter(idx); + counter_bits |= BIT(ARMV8_IDX_TO_COUNTER(idx - 1)); + + kvm_clr_pmu_events(counter_bits); + + /* We rely on the hypervisor switch code to disable guest counters */ + if (!kvm_pmu_counter_defered(attr)) { + if (armv8pmu_event_is_chained(event)) + armv8pmu_disable_counter(idx - 1); + armv8pmu_disable_counter(idx); + } } static inline int armv8pmu_enable_intens(int idx) @@ -829,11 +850,16 @@ static int armv8pmu_set_event_filter(struct hw_perf_event *event, if (!attr->exclude_kernel) config_base |= ARMV8_PMU_INCLUDE_EL2; } else { - if (attr->exclude_kernel) - config_base |= ARMV8_PMU_EXCLUDE_EL1; - if (!attr->exclude_hv) + if (!attr->exclude_hv && !attr->exclude_host) config_base |= ARMV8_PMU_INCLUDE_EL2; } + + /* + * Filter out !VHE kernels and guest kernels + */ + if (attr->exclude_kernel) + config_base |= ARMV8_PMU_EXCLUDE_EL1; + if (attr->exclude_user) config_base |= ARMV8_PMU_EXCLUDE_EL0; @@ -863,6 +889,9 @@ static void armv8pmu_reset(void *info) armv8pmu_disable_intens(idx); } + /* Clear the counters we flip at guest entry/exit */ + kvm_clr_pmu_events(U32_MAX); + /* * Initialize & Reset PMNC. Request overflow interrupt for * 64 bit cycle counter but cheat in armv8pmu_write_counter(). From patchwork Fri Mar 8 12:07:43 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Murray X-Patchwork-Id: 10844585 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 0C8361390 for ; Fri, 8 Mar 2019 12:12:08 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E78542D27F for ; Fri, 8 Mar 2019 12:12:07 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id DA0802D29B; Fri, 8 Mar 2019 12:12:07 +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 6F77B2D27F for ; Fri, 8 Mar 2019 12:12:07 +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:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version: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=CsOJmNxt3TtsOx/pzOHhu1rN6gRJ4geLbTMz7iy966Q=; b=PbKj96+FPwCwsk y3JhlKogd/IaI0WKq9y5ygfPkG48KXIjIwWzTOwbaoaXx90UGo0smjuHf/HZeMRa3ls31pNetc50r GY0gm5pdm5L8lQqTf6qtXoDSOZDWX9VkmQk8W3xZdaT4L0743tYjKzCOiJZvGVToKWfmzlXhWfpAX +GK7MoNQYH+cE18xTtgyBZEkVU4aqH87uSDyuZzrrLGJV3d4ImrSIz5kqHSDiRCeVHzq92UUvC70A OcK1WFuwa4InHtPMWeT4PeqvNk/SKks9a43LFVOmpRdaP21OP1gImFumboLpIYtsuhbSusY4uqBkG hqKEXNiqTfZ8Eyu9VBDA==; 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 1h2EM9-0002e5-MY; Fri, 08 Mar 2019 12:12:05 +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 1h2EIH-0007NY-7u for linux-arm-kernel@lists.infradead.org; Fri, 08 Mar 2019 12:08:14 +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 097D3EBD; Fri, 8 Mar 2019 04:08:05 -0800 (PST) Received: from e119886-lin.cambridge.arm.com (unknown [10.37.6.16]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 18E153F706; Fri, 8 Mar 2019 04:08:02 -0800 (PST) From: Andrew Murray To: Christoffer Dall , Marc Zyngier , Catalin Marinas , Will Deacon , Mark Rutland Subject: [PATCH v11 5/8] arm64: KVM: Enable !VHE support for :G/:H perf event modifiers Date: Fri, 8 Mar 2019 12:07:43 +0000 Message-Id: <20190308120746.56897-6-andrew.murray@arm.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190308120746.56897-1-andrew.murray@arm.com> References: <20190308120746.56897-1-andrew.murray@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190308_040805_980487_224BDB87 X-CRM114-Status: GOOD ( 13.77 ) 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: Julien Thierry , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, Suzuki K Poulose 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 Enable/disable event counters as appropriate when entering and exiting the guest to enable support for guest or host only event counting. For both VHE and non-VHE we switch the counters between host/guest at EL2. The PMU may be on when we change which counters are enabled however we avoid adding an isb as we instead rely on existing context synchronisation events: the eret to enter the guest (__guest_enter) and eret in kvm_call_hyp for __kvm_vcpu_run_nvhe on returning. Signed-off-by: Andrew Murray --- arch/arm64/include/asm/kvm_host.h | 3 +++ arch/arm64/kvm/hyp/switch.c | 6 +++++ arch/arm64/kvm/pmu.c | 40 +++++++++++++++++++++++++++++++ 3 files changed, 49 insertions(+) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 4b7219128f2d..7ca4e094626d 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -498,6 +498,9 @@ static inline int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu) void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr); void kvm_clr_pmu_events(u32 clr); + +void __pmu_switch_to_host(struct kvm_cpu_context *host_ctxt); +bool __pmu_switch_to_guest(struct kvm_cpu_context *host_ctxt); #else static inline void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr) {} static inline void kvm_clr_pmu_events(u32 clr) {} diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c index 421ebf6f7086..7c543ff7e458 100644 --- a/arch/arm64/kvm/hyp/switch.c +++ b/arch/arm64/kvm/hyp/switch.c @@ -523,6 +523,7 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu) { struct kvm_cpu_context *host_ctxt; struct kvm_cpu_context *guest_ctxt; + bool pmu_switch_needed; u64 exit_code; vcpu = kern_hyp_va(vcpu); @@ -531,6 +532,8 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu) host_ctxt->__hyp_running_vcpu = vcpu; guest_ctxt = &vcpu->arch.ctxt; + pmu_switch_needed = __pmu_switch_to_guest(host_ctxt); + __sysreg_save_state_nvhe(host_ctxt); __activate_vm(kern_hyp_va(vcpu->kvm)); @@ -577,6 +580,9 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu) */ __debug_switch_to_host(vcpu); + if (pmu_switch_needed) + __pmu_switch_to_host(host_ctxt); + return exit_code; } diff --git a/arch/arm64/kvm/pmu.c b/arch/arm64/kvm/pmu.c index 43965a3cc0f4..a1cee7919953 100644 --- a/arch/arm64/kvm/pmu.c +++ b/arch/arm64/kvm/pmu.c @@ -7,6 +7,7 @@ */ #include #include +#include DECLARE_PER_CPU(kvm_host_data_t, kvm_host_data); @@ -47,3 +48,42 @@ void kvm_clr_pmu_events(u32 clr) ctx->pmu_events.events_host &= ~clr; ctx->pmu_events.events_guest &= ~clr; } + +/** + * Disable host events, enable guest events + */ +bool __hyp_text __pmu_switch_to_guest(struct kvm_cpu_context *host_ctxt) +{ + struct kvm_host_data *host; + struct kvm_pmu_events *pmu; + + host = container_of(host_ctxt, struct kvm_host_data, host_ctxt); + pmu = &host->pmu_events; + + if (pmu->events_host) + write_sysreg(pmu->events_host, pmcntenclr_el0); + + if (pmu->events_guest) + write_sysreg(pmu->events_guest, pmcntenset_el0); + + return (pmu->events_host || pmu->events_guest); +} + +/** + * Disable guest events, enable host events + */ +void __hyp_text __pmu_switch_to_host(struct kvm_cpu_context *host_ctxt) +{ + struct kvm_host_data *host; + struct kvm_pmu_events *pmu; + + host = container_of(host_ctxt, struct kvm_host_data, host_ctxt); + pmu = &host->pmu_events; + + if (pmu->events_guest) + write_sysreg(pmu->events_guest, pmcntenclr_el0); + + if (pmu->events_host) + write_sysreg(pmu->events_host, pmcntenset_el0); +} + From patchwork Fri Mar 8 12:07:44 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Murray X-Patchwork-Id: 10844577 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 657C01390 for ; 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Fri, 8 Mar 2019 04:08:05 -0800 (PST) From: Andrew Murray To: Christoffer Dall , Marc Zyngier , Catalin Marinas , Will Deacon , Mark Rutland Subject: [PATCH v11 6/8] arm64: KVM: Enable VHE support for :G/:H perf event modifiers Date: Fri, 8 Mar 2019 12:07:44 +0000 Message-Id: <20190308120746.56897-7-andrew.murray@arm.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190308120746.56897-1-andrew.murray@arm.com> References: <20190308120746.56897-1-andrew.murray@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190308_040807_696985_56AB0B2F X-CRM114-Status: GOOD ( 15.92 ) 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: Julien Thierry , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, Suzuki K Poulose 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 With VHE different exception levels are used between the host (EL2) and guest (EL1) with a shared exception level for userpace (EL0). We can take advantage of this and use the PMU's exception level filtering to avoid enabling/disabling counters in the world-switch code. Instead we just modify the counter type to include or exclude EL0 at vcpu_{load,put} time. We also ensure that trapped PMU system register writes do not re-enable EL0 when reconfiguring the backing perf events. This approach completely avoids blackout windows seen with !VHE. Suggested-by: Christoffer Dall Signed-off-by: Andrew Murray --- arch/arm/include/asm/kvm_host.h | 3 ++ arch/arm64/include/asm/kvm_host.h | 5 +- arch/arm64/kernel/perf_event.c | 6 ++- arch/arm64/kvm/pmu.c | 87 ++++++++++++++++++++++++++++++- arch/arm64/kvm/sys_regs.c | 3 ++ virt/kvm/arm/arm.c | 2 + 6 files changed, 102 insertions(+), 4 deletions(-) diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index a358cb15bb0d..3ce429954306 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -326,6 +326,9 @@ static inline void kvm_arch_vcpu_load_fp(struct kvm_vcpu *vcpu) {} static inline void kvm_arch_vcpu_ctxsync_fp(struct kvm_vcpu *vcpu) {} static inline void kvm_arch_vcpu_put_fp(struct kvm_vcpu *vcpu) {} +static inline void kvm_vcpu_pmu_restore_guest(struct kvm_vcpu *vcpu) {} +static inline void kvm_vcpu_pmu_restore_host(struct kvm_vcpu *vcpu) {} + static inline void kvm_arm_vhe_guest_enter(void) {} static inline void kvm_arm_vhe_guest_exit(void) {} diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 7ca4e094626d..d631528898b5 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -487,7 +487,7 @@ void kvm_arch_vcpu_put_fp(struct kvm_vcpu *vcpu); static inline bool kvm_pmu_counter_defered(struct perf_event_attr *attr) { - return attr->exclude_host; + return (!has_vhe() && attr->exclude_host); } #ifdef CONFIG_KVM /* Avoid conflicts with core headers if CONFIG_KVM=n */ @@ -501,6 +501,9 @@ void kvm_clr_pmu_events(u32 clr); void __pmu_switch_to_host(struct kvm_cpu_context *host_ctxt); bool __pmu_switch_to_guest(struct kvm_cpu_context *host_ctxt); + +void kvm_vcpu_pmu_restore_guest(struct kvm_vcpu *vcpu); +void kvm_vcpu_pmu_restore_host(struct kvm_vcpu *vcpu); #else static inline void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr) {} static inline void kvm_clr_pmu_events(u32 clr) {} diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c index 64f02a9fd7cd..a121a82fc54c 100644 --- a/arch/arm64/kernel/perf_event.c +++ b/arch/arm64/kernel/perf_event.c @@ -847,8 +847,12 @@ static int armv8pmu_set_event_filter(struct hw_perf_event *event, * with other architectures (x86 and Power). */ if (is_kernel_in_hyp_mode()) { - if (!attr->exclude_kernel) + if (!attr->exclude_kernel && !attr->exclude_host) config_base |= ARMV8_PMU_INCLUDE_EL2; + if (attr->exclude_guest) + config_base |= ARMV8_PMU_EXCLUDE_EL1; + if (attr->exclude_host) + config_base |= ARMV8_PMU_EXCLUDE_EL0; } else { if (!attr->exclude_hv && !attr->exclude_host) config_base |= ARMV8_PMU_INCLUDE_EL2; diff --git a/arch/arm64/kvm/pmu.c b/arch/arm64/kvm/pmu.c index a1cee7919953..a0830c70ece5 100644 --- a/arch/arm64/kvm/pmu.c +++ b/arch/arm64/kvm/pmu.c @@ -12,11 +12,19 @@ DECLARE_PER_CPU(kvm_host_data_t, kvm_host_data); /* - * Given the exclude_{host,guest} attributes, determine if we are going - * to need to switch counters at guest entry/exit. + * Given the perf event attributes and system type, determine + * if we are going to need to switch counters at guest entry/exit. */ static bool kvm_pmu_switch_needed(struct perf_event_attr *attr) { + /** + * With VHE the guest kernel runs at EL1 and the host at EL2, + * where user (EL0) is excluded then we have no reason to switch + * counters. + */ + if (has_vhe() && attr->exclude_user) + return false; + /* Only switch if attributes are different */ return (attr->exclude_host ^ attr->exclude_guest); } @@ -87,3 +95,78 @@ void __hyp_text __pmu_switch_to_host(struct kvm_cpu_context *host_ctxt) write_sysreg(pmu->events_host, pmcntenset_el0); } +/* + * Modify ARMv8 PMU events to include EL0 counting + */ +static void kvm_vcpu_pmu_enable_el0(unsigned long events) +{ + u64 typer; + u32 counter; + + for_each_set_bit(counter, &events, 32) { + write_sysreg(counter, pmselr_el0); + isb(); + typer = read_sysreg(pmxevtyper_el0) & ~ARMV8_PMU_EXCLUDE_EL0; + write_sysreg(typer, pmxevtyper_el0); + isb(); + } +} + +/* + * Modify ARMv8 PMU events to exclude EL0 counting + */ +static void kvm_vcpu_pmu_disable_el0(unsigned long events) +{ + u64 typer; + u32 counter; + + for_each_set_bit(counter, &events, 32) { + write_sysreg(counter, pmselr_el0); + isb(); + typer = read_sysreg(pmxevtyper_el0) | ARMV8_PMU_EXCLUDE_EL0; + write_sysreg(typer, pmxevtyper_el0); + isb(); + } +} + +/* + * On VHE ensure that only guest events have EL0 counting enabled + */ +void kvm_vcpu_pmu_restore_guest(struct kvm_vcpu *vcpu) +{ + struct kvm_cpu_context *host_ctxt; + struct kvm_host_data *host; + u32 events_guest, events_host; + + if (!has_vhe()) + return; + + host_ctxt = vcpu->arch.host_cpu_context; + host = container_of(host_ctxt, struct kvm_host_data, host_ctxt); + events_guest = host->pmu_events.events_guest; + events_host = host->pmu_events.events_host; + + kvm_vcpu_pmu_enable_el0(events_guest); + kvm_vcpu_pmu_disable_el0(events_host); +} + +/* + * On VHE ensure that only guest host have EL0 counting enabled + */ +void kvm_vcpu_pmu_restore_host(struct kvm_vcpu *vcpu) +{ + struct kvm_cpu_context *host_ctxt; + struct kvm_host_data *host; + u32 events_guest, events_host; + + if (!has_vhe()) + return; + + host_ctxt = vcpu->arch.host_cpu_context; + host = container_of(host_ctxt, struct kvm_host_data, host_ctxt); + events_guest = host->pmu_events.events_guest; + events_host = host->pmu_events.events_host; + + kvm_vcpu_pmu_enable_el0(events_host); + kvm_vcpu_pmu_disable_el0(events_guest); +} diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index c936aa40c3f4..209f9dd97bcb 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -695,6 +695,7 @@ static bool access_pmcr(struct kvm_vcpu *vcpu, struct sys_reg_params *p, val |= p->regval & ARMV8_PMU_PMCR_MASK; __vcpu_sys_reg(vcpu, PMCR_EL0) = val; kvm_pmu_handle_pmcr(vcpu, val); + kvm_vcpu_pmu_restore_guest(vcpu); } else { /* PMCR.P & PMCR.C are RAZ */ val = __vcpu_sys_reg(vcpu, PMCR_EL0) @@ -850,6 +851,7 @@ static bool access_pmu_evtyper(struct kvm_vcpu *vcpu, struct sys_reg_params *p, if (p->is_write) { kvm_pmu_set_counter_event_type(vcpu, p->regval, idx); __vcpu_sys_reg(vcpu, reg) = p->regval & ARMV8_PMU_EVTYPE_MASK; + kvm_vcpu_pmu_restore_guest(vcpu); } else { p->regval = __vcpu_sys_reg(vcpu, reg) & ARMV8_PMU_EVTYPE_MASK; } @@ -875,6 +877,7 @@ static bool access_pmcnten(struct kvm_vcpu *vcpu, struct sys_reg_params *p, /* accessing PMCNTENSET_EL0 */ __vcpu_sys_reg(vcpu, PMCNTENSET_EL0) |= val; kvm_pmu_enable_counter(vcpu, val); + kvm_vcpu_pmu_restore_guest(vcpu); } else { /* accessing PMCNTENCLR_EL0 */ __vcpu_sys_reg(vcpu, PMCNTENSET_EL0) &= ~val; diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c index 6958b98b8d52..1306bf0ad025 100644 --- a/virt/kvm/arm/arm.c +++ b/virt/kvm/arm/arm.c @@ -385,6 +385,7 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) kvm_timer_vcpu_load(vcpu); kvm_vcpu_load_sysregs(vcpu); kvm_arch_vcpu_load_fp(vcpu); + kvm_vcpu_pmu_restore_guest(vcpu); if (single_task_running()) vcpu_clear_wfe_traps(vcpu); @@ -398,6 +399,7 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) kvm_vcpu_put_sysregs(vcpu); kvm_timer_vcpu_put(vcpu); kvm_vgic_put(vcpu); + kvm_vcpu_pmu_restore_host(vcpu); vcpu->cpu = -1; From patchwork Fri Mar 8 12:07:45 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Murray X-Patchwork-Id: 10844579 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 628B7139A for ; Fri, 8 Mar 2019 12:09:27 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4AC492CA32 for ; Fri, 8 Mar 2019 12:09:27 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3F0052CA41; 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Fri, 8 Mar 2019 04:08:07 -0800 (PST) From: Andrew Murray To: Christoffer Dall , Marc Zyngier , Catalin Marinas , Will Deacon , Mark Rutland Subject: [PATCH v11 7/8] arm64: KVM: avoid isb's by using direct pmxevtyper sysreg Date: Fri, 8 Mar 2019 12:07:45 +0000 Message-Id: <20190308120746.56897-8-andrew.murray@arm.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190308120746.56897-1-andrew.murray@arm.com> References: <20190308120746.56897-1-andrew.murray@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190308_040810_026693_05E72459 X-CRM114-Status: GOOD ( 16.56 ) 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: Julien Thierry , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, Suzuki K Poulose 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 Upon entering or exiting a guest we may modify multiple PMU counters to enable of disable EL0 filtering. We presently do this via the indirect PMXEVTYPER_EL0 system register (where the counter we modify is selected by PMSELR). With this approach it is necessary to order the writes via isb instructions such that we select the correct counter before modifying it. Let's avoid potentially expensive instruction barriers by using the direct PMEVTYPER_EL0 registers instead. As the change to counter type relates only to EL0 filtering we can rely on the implicit instruction barrier which occurs when we transition from EL2 to EL1 on entering the guest. On returning to userspace we can, at the latest, rely on the implicit barrier between EL2 and EL0. We can also depend on the explicit isb in armv8pmu_select_counter to order our write against any other kernel changes by the PMU driver to the type register as a result of preemption. Signed-off-by: Andrew Murray --- arch/arm64/kvm/pmu.c | 84 ++++++++++++++++++++++++++++++++++++++------ 1 file changed, 74 insertions(+), 10 deletions(-) diff --git a/arch/arm64/kvm/pmu.c b/arch/arm64/kvm/pmu.c index a0830c70ece5..1cfc298d9a3b 100644 --- a/arch/arm64/kvm/pmu.c +++ b/arch/arm64/kvm/pmu.c @@ -95,6 +95,74 @@ void __hyp_text __pmu_switch_to_host(struct kvm_cpu_context *host_ctxt) write_sysreg(pmu->events_host, pmcntenset_el0); } +#define PMEVTYPER_READ_CASE(idx) \ + case idx: \ + return read_sysreg(pmevtyper##idx##_el0) + +#define PMEVTYPER_WRITE_CASE(idx) \ + case idx: \ + write_sysreg(val, pmevtyper##idx##_el0); \ + break + +#define PMEVTYPER_CASES(readwrite) \ + PMEVTYPER_##readwrite##_CASE(0); \ + PMEVTYPER_##readwrite##_CASE(1); \ + PMEVTYPER_##readwrite##_CASE(2); \ + PMEVTYPER_##readwrite##_CASE(3); \ + PMEVTYPER_##readwrite##_CASE(4); \ + PMEVTYPER_##readwrite##_CASE(5); \ + PMEVTYPER_##readwrite##_CASE(6); \ + PMEVTYPER_##readwrite##_CASE(7); \ + PMEVTYPER_##readwrite##_CASE(8); \ + PMEVTYPER_##readwrite##_CASE(9); \ + PMEVTYPER_##readwrite##_CASE(10); \ + PMEVTYPER_##readwrite##_CASE(11); \ + PMEVTYPER_##readwrite##_CASE(12); \ + PMEVTYPER_##readwrite##_CASE(13); \ + PMEVTYPER_##readwrite##_CASE(14); \ + PMEVTYPER_##readwrite##_CASE(15); \ + PMEVTYPER_##readwrite##_CASE(16); \ + PMEVTYPER_##readwrite##_CASE(17); \ + PMEVTYPER_##readwrite##_CASE(18); \ + PMEVTYPER_##readwrite##_CASE(19); \ + PMEVTYPER_##readwrite##_CASE(20); \ + PMEVTYPER_##readwrite##_CASE(21); \ + PMEVTYPER_##readwrite##_CASE(22); \ + PMEVTYPER_##readwrite##_CASE(23); \ + PMEVTYPER_##readwrite##_CASE(24); \ + PMEVTYPER_##readwrite##_CASE(25); \ + PMEVTYPER_##readwrite##_CASE(26); \ + PMEVTYPER_##readwrite##_CASE(27); \ + PMEVTYPER_##readwrite##_CASE(28); \ + PMEVTYPER_##readwrite##_CASE(29); \ + PMEVTYPER_##readwrite##_CASE(30) + +/* + * Read a value direct from PMEVTYPER + */ +static u64 kvm_vcpu_pmu_read_evtype_direct(int idx) +{ + switch (idx) { + PMEVTYPER_CASES(READ); + default: + WARN_ON(1); + } + + return 0; +} + +/* + * Write a value direct to PMEVTYPER + */ +static void kvm_vcpu_pmu_write_evtype_direct(int idx, u32 val) +{ + switch (idx) { + PMEVTYPER_CASES(WRITE); + default: + WARN_ON(1); + } +} + /* * Modify ARMv8 PMU events to include EL0 counting */ @@ -104,11 +172,9 @@ static void kvm_vcpu_pmu_enable_el0(unsigned long events) u32 counter; for_each_set_bit(counter, &events, 32) { - write_sysreg(counter, pmselr_el0); - isb(); - typer = read_sysreg(pmxevtyper_el0) & ~ARMV8_PMU_EXCLUDE_EL0; - write_sysreg(typer, pmxevtyper_el0); - isb(); + typer = kvm_vcpu_pmu_read_evtype_direct(counter); + typer &= ~ARMV8_PMU_EXCLUDE_EL0; + kvm_vcpu_pmu_write_evtype_direct(counter, typer); } } @@ -121,11 +187,9 @@ static void kvm_vcpu_pmu_disable_el0(unsigned long events) u32 counter; for_each_set_bit(counter, &events, 32) { - write_sysreg(counter, pmselr_el0); - isb(); - typer = read_sysreg(pmxevtyper_el0) | ARMV8_PMU_EXCLUDE_EL0; - write_sysreg(typer, pmxevtyper_el0); - isb(); + typer = kvm_vcpu_pmu_read_evtype_direct(counter); + typer |= ARMV8_PMU_EXCLUDE_EL0; + kvm_vcpu_pmu_write_evtype_direct(counter, typer); } } From patchwork Fri Mar 8 12:07:46 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Murray X-Patchwork-Id: 10844581 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 19E4A139A for ; Fri, 8 Mar 2019 12:09:33 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 004AB2D228 for ; Fri, 8 Mar 2019 12:09:33 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E74FC2D27F; Fri, 8 Mar 2019 12:09:32 +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 72BBC2D228 for ; 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Fri, 08 Mar 2019 12:09:28 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h2EIO-0007V5-3Z for linux-arm-kernel@lists.infradead.org; Fri, 08 Mar 2019 12:08:34 +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 BDF311596; Fri, 8 Mar 2019 04:08:11 -0800 (PST) Received: from e119886-lin.cambridge.arm.com (unknown [10.37.6.16]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id CD0943F762; Fri, 8 Mar 2019 04:08:09 -0800 (PST) From: Andrew Murray To: Christoffer Dall , Marc Zyngier , Catalin Marinas , Will Deacon , Mark Rutland Subject: [PATCH v11 8/8] arm64: docs: document perf event attributes Date: Fri, 8 Mar 2019 12:07:46 +0000 Message-Id: <20190308120746.56897-9-andrew.murray@arm.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190308120746.56897-1-andrew.murray@arm.com> References: <20190308120746.56897-1-andrew.murray@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190308_040812_347232_C86CD162 X-CRM114-Status: GOOD ( 14.17 ) 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: Julien Thierry , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, Suzuki K Poulose 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 The interaction between the exclude_{host,guest} flags, exclude_{user,kernel,hv} flags and presence of VHE can result in different exception levels being filtered by the ARMv8 PMU. As this can be confusing let's document how they work on arm64. Signed-off-by: Andrew Murray --- Documentation/arm64/perf.txt | 74 ++++++++++++++++++++++++++++++++++++ 1 file changed, 74 insertions(+) create mode 100644 Documentation/arm64/perf.txt diff --git a/Documentation/arm64/perf.txt b/Documentation/arm64/perf.txt new file mode 100644 index 000000000000..604446c1f720 --- /dev/null +++ b/Documentation/arm64/perf.txt @@ -0,0 +1,74 @@ +Perf Event Attributes +===================== + +Author: Andrew Murray +Date: 2019-03-06 + +exclude_user +------------ + +This attribute excludes userspace. + +Userspace always runs at EL0 and thus this attribute will exclude EL0. + + +exclude_kernel +-------------- + +This attribute excludes the kernel. + +The kernel runs at EL2 with VHE and EL1 without. Guest kernels always run +at EL1. + +This attribute will exclude EL1 and additionally EL2 on a VHE system. + + +exclude_hv +---------- + +This attribute excludes the hypervisor, we ignore this flag on a VHE system +as we consider the host kernel to be the hypervisor. + +On a non-VHE system we consider the hypervisor to be any code that runs at +EL2 which is predominantly used for guest/host transitions. + +This attribute will exclude EL2 on a non-VHE system. + + +exclude_host / exclude_guest +---------------------------- + +This attribute excludes the KVM host. + +The KVM host may run at EL0 (userspace), EL1 (non-VHE kernel) and EL2 (VHE +kernel or non-VHE hypervisor). + +The KVM guest may run at EL0 (userspace) and EL1 (kernel). + +Due to the overlapping exception levels between host and guests we cannot +exclusively rely on the PMU's hardware exception filtering - therefore we +must enable/disable counting on the entry and exit to the guest. This is +performed differently on VHE and non-VHE systems. + +For non-VHE systems we exclude EL2 for exclude_host - upon entering and +exiting the guest we disable/enable the event as appropriate based on the +exclude_host and exclude_guest attributes. + +For VHE systems we exclude EL1 for exclude_guest and exclude both EL0,EL2 +for exclude_host. Upon entering and exiting the guest we modify the event +to include/exclude EL0 as appropriate based on the exclude_host and +exclude_guest attributes. + + +Accuracy +-------- + +On non-VHE systems we enable/disable counters on the entry/exit of +host/guest transition at EL2 - however there is a period of time between +enabling/disabling the counters and entering/exiting the guest. We are +able to eliminate counters counting host events on the boundaries of guest +entry/exit when counting guest events by filtering out EL2 for +exclude_host. However when using !exclude_hv there is a small blackout +window at the guest entry/exit where host events are not captured. + +On VHE systems there are no blackout windows.