diff options
| author | Wanpeng Li <wanpengli@tencent.com> | 2019-06-11 20:23:50 +0800 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2019-07-02 18:56:05 +0200 |
| commit | 32b72ecc83b651fb8633ac4bd44957c54367699d (patch) | |
| tree | 6dea551b4900870e4fe16883a9ef9bf3130a5909 | |
| parent | 715062970f3748fbbf55c1a8cb495051760a65c1 (diff) | |
KVM: X86: Expose PV_SCHED_YIELD CPUID feature bit to guest
Expose PV_SCHED_YIELD feature bit to guest, the guest can check this
feature bit before using paravirtualized sched yield.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | Documentation/virtual/kvm/cpuid.txt | 4 | ||||
| -rw-r--r-- | arch/x86/kvm/cpuid.c | 3 |
2 files changed, 6 insertions, 1 deletions
diff --git a/Documentation/virtual/kvm/cpuid.txt b/Documentation/virtual/kvm/cpuid.txt index 97ca1940a0dc..979a77ba5377 100644 --- a/Documentation/virtual/kvm/cpuid.txt +++ b/Documentation/virtual/kvm/cpuid.txt @@ -66,6 +66,10 @@ KVM_FEATURE_PV_SEND_IPI || 11 || guest checks this feature bit || || before using paravirtualized || || send IPIs. ------------------------------------------------------------------------------ +KVM_FEATURE_PV_SCHED_YIELD || 13 || guest checks this feature bit + || || before using paravirtualized + || || sched yield. +------------------------------------------------------------------------------ KVM_FEATURE_CLOCKSOURCE_STABLE_BIT || 24 || host will warn if no guest-side || || per-cpu warps are expected in || || kvmclock. diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 68c74e948e28..004cbd84c351 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -659,7 +659,8 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, (1 << KVM_FEATURE_PV_TLB_FLUSH) | (1 << KVM_FEATURE_ASYNC_PF_VMEXIT) | (1 << KVM_FEATURE_PV_SEND_IPI) | - (1 << KVM_FEATURE_POLL_CONTROL); + (1 << KVM_FEATURE_POLL_CONTROL) | + (1 << KVM_FEATURE_PV_SCHED_YIELD); if (sched_info_on()) entry->eax |= (1 << KVM_FEATURE_STEAL_TIME); |