From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id B1E0D25777 for ; Mon, 11 Nov 2024 15:58:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731340701; cv=none; b=JPx0hAdS+oBd52UfdhsU2yB+4AcD+lHxCw4f+80qYfks9qy0ZDPyRzlQUc2+vVNWFU8PsXIOWij6YvVyx0Kio8+s7obQImMoS1yTEntkQe0lQieUqbXyZKDGpXxiHU6M4A4zut0wGq3lT5K5C3XspThADLBs/C/cJjGzKFqKGYY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731340701; c=relaxed/simple; bh=0sphRx5Ps8yfDU0yMbsGpUkaZxlroZ618ELGs/t57hk=; h=Message-ID:Date:MIME-Version:Subject:From:To:Cc:References: In-Reply-To:Content-Type; b=Eo8XEnruYYC4dXQb0Dan6G9IovqyIoeS4zhD3lad6t1r2sek2HOF0L4REAZ28Oww0YOOsjL+uD3KdkAGjOVMTpuNwmojO78I3LptRBnhoCoWBTjPKLfcquRqq6qU7UJhM+N0AJFeEyOsEsDaV5BRAGzLxfv0njsB9lXru1Cc/eM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com 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 83BB01474; Mon, 11 Nov 2024 07:58:46 -0800 (PST) Received: from [10.57.79.116] (unknown [10.57.79.116]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 8196D3F6A8; Mon, 11 Nov 2024 07:58:14 -0800 (PST) Message-ID: <80c6cafa-dc17-4a47-8fae-9eea03e69f15@arm.com> Date: Mon, 11 Nov 2024 15:58:13 +0000 Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 03/15] KVM: arm64: Track presence of SPE/TRBE in kvm_host_data instead of vCPU Content-Language: en-GB From: Suzuki K Poulose To: Oliver Upton , kvmarm@lists.linux.dev Cc: Marc Zyngier , Joey Gouly , Zenghui Yu , Mingwei Zhang , Colton Lewis , Alexandru Elisei , James Clark , james.clark2@arm.com References: <20241108222418.1677420-1-oliver.upton@linux.dev> <20241108222418.1677420-4-oliver.upton@linux.dev> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 11/11/2024 13:47, Suzuki K Poulose wrote: > Cc: James Clark > > Hi Oliver > > On 08/11/2024 22:24, Oliver Upton wrote: >> Add flags to kvm_host_data to track if SPE/TRBE is present + >> programmable on a per-CPU basis. Set the flags up at init rather than >> vcpu_load() as the programmability of these buffers is unlikely to >> change. >> > > Heads up, there is a similar change from James Clark here : > > https://lkml.kernel.org/r/20241101155412.1152709-6-james.clark2@arm.com Ah, bad. That patch isn't on the public list yet. Never mind ;-). I will leave James to deal with this series ;-). For context, James is trying to enable Guest filtering for CoreSight trace, v6 of that one is available here : https://lkml.kernel.org/r/20240226113044.228403-1-james.clark@arm.com Suzuki > > This change as such looks good to me. > > Suzuki > >> Signed-off-by: Oliver Upton >> --- >>   arch/arm64/include/asm/kvm_host.h  | 18 ++++++++------- >>   arch/arm64/kvm/arm.c               |  3 --- >>   arch/arm64/kvm/debug.c             | 36 ++++++++---------------------- >>   arch/arm64/kvm/hyp/nvhe/debug-sr.c |  8 +++---- >>   4 files changed, 23 insertions(+), 42 deletions(-) >> >> diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/ >> asm/kvm_host.h >> index ad514434f3fe..07da4129f1d1 100644 >> --- a/arch/arm64/include/asm/kvm_host.h >> +++ b/arch/arm64/include/asm/kvm_host.h >> @@ -610,6 +610,10 @@ struct cpu_sve_state { >>    * field. >>    */ >>   struct kvm_host_data { >> +#define KVM_HOST_DATA_FLAG_HAS_SPE    0 >> +#define KVM_HOST_DATA_FLAG_HAS_TRBE    1 >> +    unsigned long flags; >> + >>       struct kvm_cpu_context host_ctxt; >>       /* >> @@ -911,10 +915,6 @@ struct kvm_vcpu_arch { >>   #define EXCEPT_AA64_EL2_SERR    __vcpu_except_flags(7) >>   /* Guest debug is live */ >>   #define DEBUG_DIRTY        __vcpu_single_flag(iflags, BIT(4)) >> -/* Save SPE context if active  */ >> -#define DEBUG_STATE_SAVE_SPE    __vcpu_single_flag(iflags, BIT(5)) >> -/* Save TRBE context if active  */ >> -#define DEBUG_STATE_SAVE_TRBE    __vcpu_single_flag(iflags, BIT(6)) >>   /* SVE enabled for host EL0 */ >>   #define HOST_SVE_ENABLED    __vcpu_single_flag(sflags, BIT(0)) >> @@ -1310,6 +1310,12 @@ DECLARE_KVM_HYP_PER_CPU(struct kvm_host_data, >> kvm_host_data); >>        &this_cpu_ptr_hyp_sym(kvm_host_data)->f) >>   #endif >> +#define host_data_test_flag(flag)                    \ >> +    (test_bit(KVM_HOST_DATA_FLAG_##flag, host_data_ptr(flags))) >> +#define host_data_set_flag(flag)                    \ >> +    (set_bit(KVM_HOST_DATA_FLAG_##flag, host_data_ptr(flags))) >> + >> + >>   /* Check whether the FP regs are owned by the guest */ >>   static inline bool guest_owns_fp_regs(void) >>   { >> @@ -1370,10 +1376,6 @@ static inline bool >> kvm_pmu_counter_deferred(struct perf_event_attr *attr) >>       return (!has_vhe() && attr->exclude_host); >>   } >> -/* Flags for host debug state */ >> -void kvm_arch_vcpu_load_debug_state_flags(struct kvm_vcpu *vcpu); >> -void kvm_arch_vcpu_put_debug_state_flags(struct kvm_vcpu *vcpu); >> - >>   #ifdef CONFIG_KVM >>   void kvm_set_pmu_events(u64 set, struct perf_event_attr *attr); >>   void kvm_clr_pmu_events(u64 clr); >> diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c >> index ab1bf9ccf385..3822774840e1 100644 >> --- a/arch/arm64/kvm/arm.c >> +++ b/arch/arm64/kvm/arm.c >> @@ -617,15 +617,12 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, >> int cpu) >>       vcpu_set_pauth_traps(vcpu); >> -    kvm_arch_vcpu_load_debug_state_flags(vcpu); >> - >>       if (!cpumask_test_cpu(cpu, vcpu->kvm->arch.supported_cpus)) >>           vcpu_set_on_unsupported_cpu(vcpu); >>   } >>   void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) >>   { >> -    kvm_arch_vcpu_put_debug_state_flags(vcpu); >>       kvm_arch_vcpu_put_fp(vcpu); >>       if (has_vhe()) >>           kvm_vcpu_put_vhe(vcpu); >> diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c >> index 90ecf1210bd0..97d0c6fd5f61 100644 >> --- a/arch/arm64/kvm/debug.c >> +++ b/arch/arm64/kvm/debug.c >> @@ -294,40 +294,22 @@ void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) >>       } >>   } >> -void kvm_arch_vcpu_load_debug_state_flags(struct kvm_vcpu *vcpu) >> +void kvm_init_host_debug_data(void) >>   { >> -    u64 dfr0; >> +    u64 dfr0 = read_sysreg(id_aa64dfr0_el1); >> + >> +    if (cpuid_feature_extract_signed_field(dfr0, >> ID_AA64DFR0_EL1_PMUVer_SHIFT) > 0) >> +        *host_data_ptr(nr_event_counters) = FIELD_GET(ARMV8_PMU_PMCR_N, >> +                                  read_sysreg(pmcr_el0)); >> -    /* For VHE, there is nothing to do */ >>       if (has_vhe()) >>           return; >> -    dfr0 = read_sysreg(id_aa64dfr0_el1); >> -    /* >> -     * If SPE is present on this CPU and is available at current EL, >> -     * we may need to check if the host state needs to be saved. >> -     */ >>       if (cpuid_feature_extract_unsigned_field(dfr0, >> ID_AA64DFR0_EL1_PMSVer_SHIFT) && >> -        !(read_sysreg_s(SYS_PMBIDR_EL1) & BIT(PMBIDR_EL1_P_SHIFT))) >> -        vcpu_set_flag(vcpu, DEBUG_STATE_SAVE_SPE); >> +        !(read_sysreg_s(SYS_PMBIDR_EL1) & PMBIDR_EL1_P)) >> +        host_data_set_flag(HAS_SPE); >> -    /* Check if we have TRBE implemented and available at the host */ >>       if (cpuid_feature_extract_unsigned_field(dfr0, >> ID_AA64DFR0_EL1_TraceBuffer_SHIFT) && >>           !(read_sysreg_s(SYS_TRBIDR_EL1) & TRBIDR_EL1_P)) >> -        vcpu_set_flag(vcpu, DEBUG_STATE_SAVE_TRBE); >> -} >> - >> -void kvm_arch_vcpu_put_debug_state_flags(struct kvm_vcpu *vcpu) >> -{ >> -    vcpu_clear_flag(vcpu, DEBUG_STATE_SAVE_SPE); >> -    vcpu_clear_flag(vcpu, DEBUG_STATE_SAVE_TRBE); >> -} >> - >> -void kvm_init_host_debug_data(void) >> -{ >> -    u64 dfr0 = read_sysreg(id_aa64dfr0_el1); >> - >> -    if (cpuid_feature_extract_signed_field(dfr0, >> ID_AA64DFR0_EL1_PMUVer_SHIFT) > 0) >> -        *host_data_ptr(nr_event_counters) = FIELD_GET(ARMV8_PMU_PMCR_N, >> -                                  read_sysreg(pmcr_el0)); >> +        host_data_set_flag(HAS_TRBE); >>   } >> diff --git a/arch/arm64/kvm/hyp/nvhe/debug-sr.c b/arch/arm64/kvm/hyp/ >> nvhe/debug-sr.c >> index 1e2a26d0196e..858bb38e273f 100644 >> --- a/arch/arm64/kvm/hyp/nvhe/debug-sr.c >> +++ b/arch/arm64/kvm/hyp/nvhe/debug-sr.c >> @@ -82,10 +82,10 @@ static void __debug_restore_trace(u64 trfcr_el1) >>   void __debug_save_host_buffers_nvhe(struct kvm_vcpu *vcpu) >>   { >>       /* Disable and flush SPE data generation */ >> -    if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_SPE)) >> +    if (host_data_test_flag(HAS_SPE)) >>           __debug_save_spe(host_data_ptr(host_debug_state.pmscr_el1)); >>       /* Disable and flush Self-Hosted Trace generation */ >> -    if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_TRBE)) >> +    if (host_data_test_flag(HAS_TRBE)) >>           __debug_save_trace(host_data_ptr(host_debug_state.trfcr_el1)); >>   } >> @@ -96,9 +96,9 @@ void __debug_switch_to_guest(struct kvm_vcpu *vcpu) >>   void __debug_restore_host_buffers_nvhe(struct kvm_vcpu *vcpu) >>   { >> -    if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_SPE)) >> +    if (host_data_test_flag(HAS_SPE)) >> >> __debug_restore_spe(*host_data_ptr(host_debug_state.pmscr_el1)); >> -    if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_TRBE)) >> +    if (host_data_test_flag(HAS_TRBE)) >> >> __debug_restore_trace(*host_data_ptr(host_debug_state.trfcr_el1)); >>   } > >