From 9411e8b6faeb1d88d4441c63c5ec072a01b2914e Mon Sep 17 00:00:00 2001 From: Vitaly Kuznetsov Date: Wed, 25 May 2022 13:59:46 +0200 Subject: [PATCH] i386: Hyper-V XMM fast hypercall input feature Hyper-V specification allows to pass parameters for certain hypercalls using XMM registers ("XMM Fast Hypercall Input"). When the feature is in use, it allows for faster hypercalls processing as KVM can avoid reading guest's memory. KVM supports the feature since v5.14. Rename HV_HYPERCALL_{PARAMS_XMM_AVAILABLE -> XMM_INPUT_AVAILABLE} to comply with KVM. Signed-off-by: Vitaly Kuznetsov Message-Id: <20220525115949.1294004-4-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini --- docs/hyperv.txt | 6 ++++++ target/i386/cpu.c | 2 ++ target/i386/cpu.h | 1 + target/i386/kvm/hyperv-proto.h | 2 +- target/i386/kvm/kvm.c | 7 +++++++ 5 files changed, 17 insertions(+), 1 deletion(-) diff --git a/docs/hyperv.txt b/docs/hyperv.txt index 5d85569b9941..af1b10c0b3d1 100644 --- a/docs/hyperv.txt +++ b/docs/hyperv.txt @@ -249,6 +249,12 @@ Enlightened VMCS ('hv-evmcs') feature to also be enabled. Recommended: hv-evmcs (Intel) +3.23. hv-xmm-input +=================== +Hyper-V specification allows to pass parameters for certain hypercalls using XMM +registers ("XMM Fast Hypercall Input"). When the feature is in use, it allows +for faster hypercalls processing as KVM can avoid reading guest's memory. + 4. Supplementary features ========================= diff --git a/target/i386/cpu.c b/target/i386/cpu.c index 474e9b582ef3..63cec0ea68da 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -6970,6 +6970,8 @@ static Property x86_cpu_properties[] = { HYPERV_FEAT_AVIC, 0), DEFINE_PROP_BIT64("hv-emsr-bitmap", X86CPU, hyperv_features, HYPERV_FEAT_MSR_BITMAP, 0), + DEFINE_PROP_BIT64("hv-xmm-input", X86CPU, hyperv_features, + HYPERV_FEAT_XMM_INPUT, 0), DEFINE_PROP_ON_OFF_AUTO("hv-no-nonarch-coresharing", X86CPU, hyperv_no_nonarch_cs, ON_OFF_AUTO_OFF), DEFINE_PROP_BIT64("hv-syndbg", X86CPU, hyperv_features, diff --git a/target/i386/cpu.h b/target/i386/cpu.h index c7882857366d..37e95535843b 100644 --- a/target/i386/cpu.h +++ b/target/i386/cpu.h @@ -1107,6 +1107,7 @@ uint64_t x86_cpu_get_supported_feature_word(FeatureWord w, #define HYPERV_FEAT_AVIC 15 #define HYPERV_FEAT_SYNDBG 16 #define HYPERV_FEAT_MSR_BITMAP 17 +#define HYPERV_FEAT_XMM_INPUT 18 #ifndef HYPERV_SPINLOCK_NEVER_NOTIFY #define HYPERV_SPINLOCK_NEVER_NOTIFY 0xFFFFFFFF diff --git a/target/i386/kvm/hyperv-proto.h b/target/i386/kvm/hyperv-proto.h index cea18dbc0e23..f5f16474fa25 100644 --- a/target/i386/kvm/hyperv-proto.h +++ b/target/i386/kvm/hyperv-proto.h @@ -54,7 +54,7 @@ #define HV_GUEST_DEBUGGING_AVAILABLE (1u << 1) #define HV_PERF_MONITOR_AVAILABLE (1u << 2) #define HV_CPU_DYNAMIC_PARTITIONING_AVAILABLE (1u << 3) -#define HV_HYPERCALL_PARAMS_XMM_AVAILABLE (1u << 4) +#define HV_HYPERCALL_XMM_INPUT_AVAILABLE (1u << 4) #define HV_GUEST_IDLE_STATE_AVAILABLE (1u << 5) #define HV_FREQUENCY_MSRS_AVAILABLE (1u << 8) #define HV_GUEST_CRASH_MSR_AVAILABLE (1u << 10) diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c index f389bbedf204..7e6f934eda68 100644 --- a/target/i386/kvm/kvm.c +++ b/target/i386/kvm/kvm.c @@ -980,6 +980,13 @@ static struct { .bits = HV_NESTED_MSR_BITMAP} } }, + [HYPERV_FEAT_XMM_INPUT] = { + .desc = "XMM fast hypercall input (hv-xmm-input)", + .flags = { + {.func = HV_CPUID_FEATURES, .reg = R_EDX, + .bits = HV_HYPERCALL_XMM_INPUT_AVAILABLE} + } + }, }; static struct kvm_cpuid2 *try_get_hv_cpuid(CPUState *cs, int max,