diff options
| author | Nicholas Piggin | 2021-11-23 19:52:22 +1000 |
|---|---|---|
| committer | Michael Ellerman | 2021-11-24 21:09:02 +1100 |
| commit | 46dea77f790c1e7ab2e9f7452e34de0dc5da9b13 (patch) | |
| tree | af24a8dc8afc9b6493cd93ee7b9d296516edcde4 /arch/powerpc/kvm/book3s_hv_nested.c | |
| parent | d5c0e8332d82c04deee25dd6f28c5bbe84d49a73 (diff) | |
KVM: PPC: Book3S HV Nested: Avoid extra mftb() in nested entry
mftb() is expensive and one can be avoided on nested guest dispatch.
If the time checking code distinguishes between the L0 timer and the
nested HV timer, then both can be tested in the same place with the
same mftb() value.
This also nicely illustrates the relationship between the L0 and nested
HV timers.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211123095231.1036501-45-npiggin@gmail.com
Diffstat (limited to 'arch/powerpc/kvm/book3s_hv_nested.c')
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv_nested.c | 5 |
1 files changed, 0 insertions, 5 deletions
diff --git a/arch/powerpc/kvm/book3s_hv_nested.c b/arch/powerpc/kvm/book3s_hv_nested.c index 7bed0b91245e..e57c08b968c0 100644 --- a/arch/powerpc/kvm/book3s_hv_nested.c +++ b/arch/powerpc/kvm/book3s_hv_nested.c @@ -375,11 +375,6 @@ long kvmhv_enter_nested_guest(struct kvm_vcpu *vcpu) vcpu->arch.ret = RESUME_GUEST; vcpu->arch.trap = 0; do { - if (mftb() >= hdec_exp) { - vcpu->arch.trap = BOOK3S_INTERRUPT_HV_DECREMENTER; - r = RESUME_HOST; - break; - } r = kvmhv_run_single_vcpu(vcpu, hdec_exp, lpcr); } while (is_kvmppc_resume_guest(r)); |