| Message ID | 20220414132013.1588929-9-vkuznets@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: x86: hyper-v: Fine-grained TLB flush + L2 TLB flush feature | expand |
On Thu, 2022-04-14 at 15:19 +0200, Vitaly Kuznetsov wrote: > It may not be clear from where the '64' limit for the maximum sparse > bank number comes from, use HV_MAX_SPARSE_VCPU_BANKS define instead. > Use HV_VCPUS_PER_SPARSE_BANK in KVM_HV_MAX_SPARSE_VCPU_SET_BITS's > definition. Opportunistically adjust the comment around BUILD_BUG_ON(). > > No functional change. > > Suggested-by: Sean Christopherson <seanjc@google.com> > Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> > --- > arch/x86/kvm/hyperv.c | 13 ++++++------- > 1 file changed, 6 insertions(+), 7 deletions(-) > > diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c > index fc4bb0ead9fa..3cf68645a2e6 100644 > --- a/arch/x86/kvm/hyperv.c > +++ b/arch/x86/kvm/hyperv.c > @@ -43,7 +43,7 @@ > /* "Hv#1" signature */ > #define HYPERV_CPUID_SIGNATURE_EAX 0x31237648 > > -#define KVM_HV_MAX_SPARSE_VCPU_SET_BITS DIV_ROUND_UP(KVM_MAX_VCPUS, 64) > +#define KVM_HV_MAX_SPARSE_VCPU_SET_BITS DIV_ROUND_UP(KVM_MAX_VCPUS, HV_VCPUS_PER_SPARSE_BANK) > > static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer, > bool vcpu_kick); > @@ -1798,7 +1798,7 @@ static u64 kvm_get_sparse_vp_set(struct kvm *kvm, struct kvm_hv_hcall *hc, > u64 *sparse_banks, int consumed_xmm_halves, > gpa_t offset) > { > - if (hc->var_cnt > 64) > + if (hc->var_cnt > HV_MAX_SPARSE_VCPU_BANKS) > return -EINVAL; > > /* Cap var_cnt to ignore banks that cannot contain a legal VP index. */ > @@ -1969,12 +1969,11 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc) > gpa_t data_offset; > > /* > - * The Hyper-V TLFS doesn't allow more than 64 sparse banks, e.g. the > - * valid mask is a u64. Fail the build if KVM's max allowed number of > - * vCPUs (>4096) would exceed this limit, KVM will additional changes > - * for Hyper-V support to avoid setting the guest up to fail. > + * The Hyper-V TLFS doesn't allow more than HV_MAX_SPARSE_VCPU_BANKS > + * sparse banks. Fail the build if KVM's max allowed number of > + * vCPUs (>4096) exceeds this limit. > */ > - BUILD_BUG_ON(KVM_HV_MAX_SPARSE_VCPU_SET_BITS > 64); > + BUILD_BUG_ON(KVM_HV_MAX_SPARSE_VCPU_SET_BITS > HV_MAX_SPARSE_VCPU_BANKS); > > if (!hc->fast && is_guest_mode(vcpu)) { > hc->ingpa = translate_nested_gpa(vcpu, hc->ingpa, 0, NULL); Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Best regards, Maxim Levitsky
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index fc4bb0ead9fa..3cf68645a2e6 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -43,7 +43,7 @@ /* "Hv#1" signature */ #define HYPERV_CPUID_SIGNATURE_EAX 0x31237648 -#define KVM_HV_MAX_SPARSE_VCPU_SET_BITS DIV_ROUND_UP(KVM_MAX_VCPUS, 64) +#define KVM_HV_MAX_SPARSE_VCPU_SET_BITS DIV_ROUND_UP(KVM_MAX_VCPUS, HV_VCPUS_PER_SPARSE_BANK) static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer, bool vcpu_kick); @@ -1798,7 +1798,7 @@ static u64 kvm_get_sparse_vp_set(struct kvm *kvm, struct kvm_hv_hcall *hc, u64 *sparse_banks, int consumed_xmm_halves, gpa_t offset) { - if (hc->var_cnt > 64) + if (hc->var_cnt > HV_MAX_SPARSE_VCPU_BANKS) return -EINVAL; /* Cap var_cnt to ignore banks that cannot contain a legal VP index. */ @@ -1969,12 +1969,11 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc) gpa_t data_offset; /* - * The Hyper-V TLFS doesn't allow more than 64 sparse banks, e.g. the - * valid mask is a u64. Fail the build if KVM's max allowed number of - * vCPUs (>4096) would exceed this limit, KVM will additional changes - * for Hyper-V support to avoid setting the guest up to fail. + * The Hyper-V TLFS doesn't allow more than HV_MAX_SPARSE_VCPU_BANKS + * sparse banks. Fail the build if KVM's max allowed number of + * vCPUs (>4096) exceeds this limit. */ - BUILD_BUG_ON(KVM_HV_MAX_SPARSE_VCPU_SET_BITS > 64); + BUILD_BUG_ON(KVM_HV_MAX_SPARSE_VCPU_SET_BITS > HV_MAX_SPARSE_VCPU_BANKS); if (!hc->fast && is_guest_mode(vcpu)) { hc->ingpa = translate_nested_gpa(vcpu, hc->ingpa, 0, NULL);
It may not be clear from where the '64' limit for the maximum sparse bank number comes from, use HV_MAX_SPARSE_VCPU_BANKS define instead. Use HV_VCPUS_PER_SPARSE_BANK in KVM_HV_MAX_SPARSE_VCPU_SET_BITS's definition. Opportunistically adjust the comment around BUILD_BUG_ON(). No functional change. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> --- arch/x86/kvm/hyperv.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-)