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author | Nicholas Piggin <npiggin@gmail.com> | 2021-11-23 19:51:49 +1000 |
---|---|---|
committer | Michael Ellerman <mpe@ellerman.id.au> | 2021-11-24 21:08:57 +1100 |
commit | 245ebf8e7380b3d84c0aac37fbfd9306b45a3a7a (patch) | |
tree | c971581a1e6f91ba65b4b13eef7d6b4781f6b10d | |
parent | d3c8a2d3740d93778ea102d4c781746d284177bf (diff) | |
download | lwn-245ebf8e7380b3d84c0aac37fbfd9306b45a3a7a.tar.gz lwn-245ebf8e7380b3d84c0aac37fbfd9306b45a3a7a.zip |
powerpc/64s: Always set PMU control registers to frozen/disabled when not in use
KVM PMU management code looks for particular frozen/disabled bits in
the PMU registers so it knows whether it must clear them when coming
out of a guest or not. Setting this up helps KVM make these optimisations
without getting confused. Longer term the better approach might be to
move guest/host PMU switching to the perf subsystem.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211123095231.1036501-12-npiggin@gmail.com
-rw-r--r-- | arch/powerpc/kernel/cpu_setup_power.c | 4 | ||||
-rw-r--r-- | arch/powerpc/kernel/dt_cpu_ftrs.c | 6 | ||||
-rw-r--r-- | arch/powerpc/kvm/book3s_hv.c | 5 |
3 files changed, 10 insertions, 5 deletions
diff --git a/arch/powerpc/kernel/cpu_setup_power.c b/arch/powerpc/kernel/cpu_setup_power.c index a29dc8326622..3dc61e203f37 100644 --- a/arch/powerpc/kernel/cpu_setup_power.c +++ b/arch/powerpc/kernel/cpu_setup_power.c @@ -109,7 +109,7 @@ static void init_PMU_HV_ISA207(void) static void init_PMU(void) { mtspr(SPRN_MMCRA, 0); - mtspr(SPRN_MMCR0, 0); + mtspr(SPRN_MMCR0, MMCR0_FC); mtspr(SPRN_MMCR1, 0); mtspr(SPRN_MMCR2, 0); } @@ -123,7 +123,7 @@ static void init_PMU_ISA31(void) { mtspr(SPRN_MMCR3, 0); mtspr(SPRN_MMCRA, MMCRA_BHRB_DISABLE); - mtspr(SPRN_MMCR0, MMCR0_PMCCEXT); + mtspr(SPRN_MMCR0, MMCR0_FC | MMCR0_PMCCEXT); } /* diff --git a/arch/powerpc/kernel/dt_cpu_ftrs.c b/arch/powerpc/kernel/dt_cpu_ftrs.c index de59971319ab..d2b35fb9181d 100644 --- a/arch/powerpc/kernel/dt_cpu_ftrs.c +++ b/arch/powerpc/kernel/dt_cpu_ftrs.c @@ -353,7 +353,7 @@ static void init_pmu_power8(void) } mtspr(SPRN_MMCRA, 0); - mtspr(SPRN_MMCR0, 0); + mtspr(SPRN_MMCR0, MMCR0_FC); mtspr(SPRN_MMCR1, 0); mtspr(SPRN_MMCR2, 0); mtspr(SPRN_MMCRS, 0); @@ -392,7 +392,7 @@ static void init_pmu_power9(void) mtspr(SPRN_MMCRC, 0); mtspr(SPRN_MMCRA, 0); - mtspr(SPRN_MMCR0, 0); + mtspr(SPRN_MMCR0, MMCR0_FC); mtspr(SPRN_MMCR1, 0); mtspr(SPRN_MMCR2, 0); } @@ -428,7 +428,7 @@ static void init_pmu_power10(void) mtspr(SPRN_MMCR3, 0); mtspr(SPRN_MMCRA, MMCRA_BHRB_DISABLE); - mtspr(SPRN_MMCR0, MMCR0_PMCCEXT); + mtspr(SPRN_MMCR0, MMCR0_FC | MMCR0_PMCCEXT); } static int __init feat_enable_pmu_power10(struct dt_cpu_feature *f) diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 6e760f48bbaf..8bf0f6337212 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -2715,6 +2715,11 @@ static int kvmppc_core_vcpu_create_hv(struct kvm_vcpu *vcpu) #endif #endif vcpu->arch.mmcr[0] = MMCR0_FC; + if (cpu_has_feature(CPU_FTR_ARCH_31)) { + vcpu->arch.mmcr[0] |= MMCR0_PMCCEXT; + vcpu->arch.mmcra = MMCRA_BHRB_DISABLE; + } + vcpu->arch.ctrl = CTRL_RUNLATCH; /* default to host PVR, since we can't spoof it */ kvmppc_set_pvr_hv(vcpu, mfspr(SPRN_PVR)); |