diff options
| author | Jason Baron <jbaron@akamai.com> | 2021-01-14 22:27:56 -0500 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2021-02-04 05:27:30 -0500 |
| commit | b3646477d458fbe7694a15b9c78fbe2fa426b703 (patch) | |
| tree | 6b2c5379acb1a28e4ffce63fc589fc76c18fd678 /arch/x86/kvm/hyperv.c | |
| parent | 9af5471bdbb2a26a1a46cd834e9fda6db6a9670e (diff) | |
KVM: x86: use static calls to reduce kvm_x86_ops overhead
Convert kvm_x86_ops to use static calls. Note that all kvm_x86_ops are
covered here except for 'pmu_ops and 'nested ops'.
Here are some numbers running cpuid in a loop of 1 million calls averaged
over 5 runs, measured in the vm (lower is better).
Intel Xeon 3000MHz:
|default |mitigations=off
-------------------------------------
vanilla |.671s |.486s
static call|.573s(-15%)|.458s(-6%)
AMD EPYC 2500MHz:
|default |mitigations=off
-------------------------------------
vanilla |.710s |.609s
static call|.664s(-6%) |.609s(0%)
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Signed-off-by: Jason Baron <jbaron@akamai.com>
Message-Id: <e057bf1b8a7ad15652df6eeba3f907ae758d3399.1610680941.git.jbaron@akamai.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/hyperv.c')
| -rw-r--r-- | arch/x86/kvm/hyperv.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index 922c69dcca4d..5c45d80a7ce3 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -1154,7 +1154,7 @@ static int kvm_hv_set_msr_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data, addr = gfn_to_hva(kvm, gfn); if (kvm_is_error_hva(addr)) return 1; - kvm_x86_ops.patch_hypercall(vcpu, instructions); + static_call(kvm_x86_patch_hypercall)(vcpu, instructions); ((unsigned char *)instructions)[3] = 0xc3; /* ret */ if (__copy_to_user((void __user *)addr, instructions, 4)) return 1; @@ -1745,7 +1745,7 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu) * hypercall generates UD from non zero cpl and real mode * per HYPER-V spec */ - if (kvm_x86_ops.get_cpl(vcpu) != 0 || !is_protmode(vcpu)) { + if (static_call(kvm_x86_get_cpl)(vcpu) != 0 || !is_protmode(vcpu)) { kvm_queue_exception(vcpu, UD_VECTOR); return 1; } |