diff options
| author | Nicholas Piggin <npiggin@gmail.com> | 2021-11-23 19:52:19 +1000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2021-11-24 21:09:01 +1100 |
| commit | a089a6869e7f613a8d961ac65bafd127317e4c5c (patch) | |
| tree | 4e1e8b30695f1eb621699f150f6516a3cd57f4bc /arch/powerpc/kvm/book3s_hv.c | |
| parent | 9c75f65f3583b0cf467c378a1076f0b50bbc2fb1 (diff) | |
KVM: PPC: Book3S HV P9: Don't restore PSSCR if not needed
This also moves the PSSCR update in nested entry to avoid a SPR
scoreboard stall.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211123095231.1036501-42-npiggin@gmail.com
Diffstat (limited to 'arch/powerpc/kvm/book3s_hv.c')
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 7d48aa8aebb2..9da27f19a697 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -3889,7 +3889,9 @@ static int kvmhv_vcpu_entry_p9_nested(struct kvm_vcpu *vcpu, u64 time_limit, uns if (unlikely(load_vcpu_state(vcpu, &host_os_sprs))) msr = mfmsr(); /* TM restore can update msr */ - mtspr(SPRN_PSSCR_PR, vcpu->arch.psscr); + if (vcpu->arch.psscr != host_psscr) + mtspr(SPRN_PSSCR_PR, vcpu->arch.psscr); + kvmhv_save_hv_regs(vcpu, &hvregs); hvregs.lpcr = lpcr; vcpu->arch.regs.msr = vcpu->arch.shregs.msr; @@ -3930,7 +3932,6 @@ static int kvmhv_vcpu_entry_p9_nested(struct kvm_vcpu *vcpu, u64 time_limit, uns vcpu->arch.shregs.dar = mfspr(SPRN_DAR); vcpu->arch.shregs.dsisr = mfspr(SPRN_DSISR); vcpu->arch.psscr = mfspr(SPRN_PSSCR_PR); - mtspr(SPRN_PSSCR_PR, host_psscr); store_vcpu_state(vcpu); @@ -3943,6 +3944,8 @@ static int kvmhv_vcpu_entry_p9_nested(struct kvm_vcpu *vcpu, u64 time_limit, uns timer_rearm_host_dec(*tb); restore_p9_host_os_sprs(vcpu, &host_os_sprs); + if (vcpu->arch.psscr != host_psscr) + mtspr(SPRN_PSSCR_PR, host_psscr); return trap; } |