Am 11.12.2013 19:53, schrieb Marcelo Tosatti: > On Sun, Dec 08, 2013 at 10:33:38PM +1100, Vadim Rozenfeld wrote: >> Signed-off: Peter Lieven <p...@dlh.net> >> Signed-off: Gleb Natapov <g...@redhat.com> >> Signed-off: Vadim Rozenfeld <vroze...@redhat.com> >> >> v1 -> v2 >> 1. mark TSC page dirty as suggested by >> Eric Northup <digitale...@google.com> and Gleb >> 2. disable local irq when calling get_kernel_ns, >> as it was done by Peter Lieven <p...@dlhnet.de> >> 3. move check for TSC page enable from second patch >> to this one. >> >> --- >> arch/x86/include/asm/kvm_host.h | 2 ++ >> arch/x86/include/uapi/asm/hyperv.h | 13 +++++++++++++ >> arch/x86/kvm/x86.c | 39 >> +++++++++++++++++++++++++++++++++++++- >> include/uapi/linux/kvm.h | 1 + >> 4 files changed, 54 insertions(+), 1 deletion(-) >> >> diff --git a/arch/x86/include/asm/kvm_host.h >> b/arch/x86/include/asm/kvm_host.h >> index ae5d783..2fd0753 100644 >> --- a/arch/x86/include/asm/kvm_host.h >> +++ b/arch/x86/include/asm/kvm_host.h >> @@ -605,6 +605,8 @@ struct kvm_arch { >> /* fields used by HYPER-V emulation */ >> u64 hv_guest_os_id; >> u64 hv_hypercall; >> + u64 hv_ref_count; >> + u64 hv_tsc_page; >> >> #ifdef CONFIG_KVM_MMU_AUDIT >> int audit_point; >> diff --git a/arch/x86/include/uapi/asm/hyperv.h >> b/arch/x86/include/uapi/asm/hyperv.h >> index b8f1c01..462efe7 100644 >> --- a/arch/x86/include/uapi/asm/hyperv.h >> +++ b/arch/x86/include/uapi/asm/hyperv.h >> @@ -28,6 +28,9 @@ >> /* Partition Reference Counter (HV_X64_MSR_TIME_REF_COUNT) available*/ >> #define HV_X64_MSR_TIME_REF_COUNT_AVAILABLE (1 << 1) >> >> +/* A partition's reference time stamp counter (TSC) page */ >> +#define HV_X64_MSR_REFERENCE_TSC 0x40000021 >> + >> /* >> * There is a single feature flag that signifies the presence of the MSR >> * that can be used to retrieve both the local APIC Timer frequency as >> @@ -198,6 +201,9 @@ >> #define HV_X64_MSR_APIC_ASSIST_PAGE_ADDRESS_MASK \ >> (~((1ull << HV_X64_MSR_APIC_ASSIST_PAGE_ADDRESS_SHIFT) - 1)) >> >> +#define HV_X64_MSR_TSC_REFERENCE_ENABLE 0x00000001 >> +#define HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT 12 >> + >> #define HV_PROCESSOR_POWER_STATE_C0 0 >> #define HV_PROCESSOR_POWER_STATE_C1 1 >> #define HV_PROCESSOR_POWER_STATE_C2 2 >> @@ -210,4 +216,11 @@ >> #define HV_STATUS_INVALID_ALIGNMENT 4 >> #define HV_STATUS_INSUFFICIENT_BUFFERS 19 >> >> +typedef struct _HV_REFERENCE_TSC_PAGE { >> + __u32 tsc_sequence; >> + __u32 res1; >> + __u64 tsc_scale; >> + __s64 tsc_offset; >> +} HV_REFERENCE_TSC_PAGE, *PHV_REFERENCE_TSC_PAGE; >> + >> #endif >> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c >> index 21ef1ba..5e4e495a 100644 >> --- a/arch/x86/kvm/x86.c >> +++ b/arch/x86/kvm/x86.c >> @@ -840,7 +840,7 @@ EXPORT_SYMBOL_GPL(kvm_rdpmc); >> static u32 msrs_to_save[] = { >> MSR_KVM_SYSTEM_TIME, MSR_KVM_WALL_CLOCK, >> MSR_KVM_SYSTEM_TIME_NEW, MSR_KVM_WALL_CLOCK_NEW, >> - HV_X64_MSR_GUEST_OS_ID, HV_X64_MSR_HYPERCALL, >> + HV_X64_MSR_GUEST_OS_ID, HV_X64_MSR_HYPERCALL, HV_X64_MSR_TIME_REF_COUNT, >> HV_X64_MSR_APIC_ASSIST_PAGE, MSR_KVM_ASYNC_PF_EN, MSR_KVM_STEAL_TIME, >> MSR_KVM_PV_EOI_EN, >> MSR_IA32_SYSENTER_CS, MSR_IA32_SYSENTER_ESP, MSR_IA32_SYSENTER_EIP, >> @@ -1826,6 +1826,8 @@ static bool kvm_hv_msr_partition_wide(u32 msr) >> switch (msr) { >> case HV_X64_MSR_GUEST_OS_ID: >> case HV_X64_MSR_HYPERCALL: >> + case HV_X64_MSR_REFERENCE_TSC: >> + case HV_X64_MSR_TIME_REF_COUNT: >> r = true; >> break; >> } >> @@ -1865,6 +1867,29 @@ static int set_msr_hyperv_pw(struct kvm_vcpu *vcpu, >> u32 msr, u64 data) >> if (__copy_to_user((void __user *)addr, instructions, 4)) >> return 1; >> kvm->arch.hv_hypercall = data; >> + local_irq_disable(); >> + kvm->arch.hv_ref_count = get_kernel_ns() + >> kvm->arch.kvmclock_offset; >> + local_irq_enable(); > > Where does the docs say that HV_X64_MSR_HYPERCALL is the where the clock > starts counting? > > No need to store kvmclock_offset in hv_ref_count? (moreover > the name is weird, better name would be "hv_ref_start_time". > >> + break; >> + } >> + case HV_X64_MSR_REFERENCE_TSC: { >> + u64 gfn; >> + unsigned long addr; >> + HV_REFERENCE_TSC_PAGE tsc_ref; >> + tsc_ref.tsc_sequence = 0; >> + if (!(data & HV_X64_MSR_TSC_REFERENCE_ENABLE)) { >> + kvm->arch.hv_tsc_page = data; >> + break; >> + } >> + gfn = data >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT; >> + addr = gfn_to_hva(kvm, data >> >> + HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT); >> + if (kvm_is_error_hva(addr)) >> + return 1; >> + if (__copy_to_user((void __user *)addr, &tsc_ref, >> sizeof(tsc_ref))) >> + return 1; >> + mark_page_dirty(kvm, gfn); >> + kvm->arch.hv_tsc_page = data; >> break; >> } >> default: >> @@ -2291,6 +2316,17 @@ static int get_msr_hyperv_pw(struct kvm_vcpu *vcpu, >> u32 msr, u64 *pdata) >> case HV_X64_MSR_HYPERCALL: >> data = kvm->arch.hv_hypercall; >> break; >> + case HV_X64_MSR_TIME_REF_COUNT: { >> + u64 now_ns; >> + local_irq_disable(); >> + now_ns = get_kernel_ns() + kvm->arch.kvmclock_offset; >> + data = div_u64(now_ns - kvm->arch.hv_ref_count, 100); >> + local_irq_enable(); > > No need for irq disable/enable pairs.
KVM_GET_CLOCK / KVM_SET_CLOCK do the irq disable/enable pairs. What is right? Peter -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html