From: Oliver Upton oliver.upton@linux.dev
Add flags to kvm_host_data to track if SPE/TRBE is present + programmable on a per-CPU basis. Set the flags up at init rather than vcpu_load() as the programmability of these buffers is unlikely to change.
Reviewed-by: James Clark james.clark@linaro.org Tested-by: James Clark james.clark@linaro.org Signed-off-by: Oliver Upton oliver.upton@linux.dev Link: https://lore.kernel.org/r/20241219224116.3941496-4-oliver.upton@linux.dev Signed-off-by: Marc Zyngier maz@kernel.org --- arch/arm64/include/asm/kvm_host.h | 19 +++++++++------- arch/arm64/kvm/arm.c | 3 --- arch/arm64/kvm/debug.c | 36 ++++++++---------------------- arch/arm64/kvm/hyp/nvhe/debug-sr.c | 8 +++---- 4 files changed, 24 insertions(+), 42 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 064f5dfca7f4..fb252d540850 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -610,6 +610,10 @@ struct cpu_sve_state { * field. */ struct kvm_host_data { +#define KVM_HOST_DATA_FLAG_HAS_SPE 0 +#define KVM_HOST_DATA_FLAG_HAS_TRBE 1 + unsigned long flags; + struct kvm_cpu_context host_ctxt;
/* @@ -911,10 +915,6 @@ struct kvm_vcpu_arch { #define EXCEPT_AA64_EL2_SERR __vcpu_except_flags(7) /* Guest debug is live */ #define DEBUG_DIRTY __vcpu_single_flag(iflags, BIT(4)) -/* Save SPE context if active */ -#define DEBUG_STATE_SAVE_SPE __vcpu_single_flag(iflags, BIT(5)) -/* Save TRBE context if active */ -#define DEBUG_STATE_SAVE_TRBE __vcpu_single_flag(iflags, BIT(6))
/* SVE enabled for host EL0 */ #define HOST_SVE_ENABLED __vcpu_single_flag(sflags, BIT(0)) @@ -1310,6 +1310,13 @@ DECLARE_KVM_HYP_PER_CPU(struct kvm_host_data, kvm_host_data); &this_cpu_ptr_hyp_sym(kvm_host_data)->f) #endif
+#define host_data_test_flag(flag) \ + (test_bit(KVM_HOST_DATA_FLAG_##flag, host_data_ptr(flags))) +#define host_data_set_flag(flag) \ + set_bit(KVM_HOST_DATA_FLAG_##flag, host_data_ptr(flags)) +#define host_data_clear_flag(flag) \ + clear_bit(KVM_HOST_DATA_FLAG_##flag, host_data_ptr(flags)) + /* Check whether the FP regs are owned by the guest */ static inline bool guest_owns_fp_regs(void) { @@ -1370,10 +1377,6 @@ static inline bool kvm_pmu_counter_deferred(struct perf_event_attr *attr) return (!has_vhe() && attr->exclude_host); }
-/* Flags for host debug state */ -void kvm_arch_vcpu_load_debug_state_flags(struct kvm_vcpu *vcpu); -void kvm_arch_vcpu_put_debug_state_flags(struct kvm_vcpu *vcpu); - #ifdef CONFIG_KVM void kvm_set_pmu_events(u64 set, struct perf_event_attr *attr); void kvm_clr_pmu_events(u64 clr); diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index ab1bf9ccf385..3822774840e1 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -617,15 +617,12 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
vcpu_set_pauth_traps(vcpu);
- kvm_arch_vcpu_load_debug_state_flags(vcpu); - if (!cpumask_test_cpu(cpu, vcpu->kvm->arch.supported_cpus)) vcpu_set_on_unsupported_cpu(vcpu); }
void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) { - kvm_arch_vcpu_put_debug_state_flags(vcpu); kvm_arch_vcpu_put_fp(vcpu); if (has_vhe()) kvm_vcpu_put_vhe(vcpu); diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c index d8ea6fe6a2a2..1ee2fd765b62 100644 --- a/arch/arm64/kvm/debug.c +++ b/arch/arm64/kvm/debug.c @@ -294,40 +294,22 @@ void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) } }
-void kvm_arch_vcpu_load_debug_state_flags(struct kvm_vcpu *vcpu) +void kvm_init_host_debug_data(void) { - u64 dfr0; + u64 dfr0 = read_sysreg(id_aa64dfr0_el1); + + if (cpuid_feature_extract_signed_field(dfr0, ID_AA64DFR0_EL1_PMUVer_SHIFT) > 0) + *host_data_ptr(nr_event_counters) = FIELD_GET(ARMV8_PMU_PMCR_N, + read_sysreg(pmcr_el0));
- /* For VHE, there is nothing to do */ if (has_vhe()) return;
- dfr0 = read_sysreg(id_aa64dfr0_el1); - /* - * If SPE is present on this CPU and is available at current EL, - * we may need to check if the host state needs to be saved. - */ if (cpuid_feature_extract_unsigned_field(dfr0, ID_AA64DFR0_EL1_PMSVer_SHIFT) && - !(read_sysreg_s(SYS_PMBIDR_EL1) & BIT(PMBIDR_EL1_P_SHIFT))) - vcpu_set_flag(vcpu, DEBUG_STATE_SAVE_SPE); + !(read_sysreg_s(SYS_PMBIDR_EL1) & PMBIDR_EL1_P)) + host_data_set_flag(HAS_SPE);
- /* Check if we have TRBE implemented and available at the host */ if (cpuid_feature_extract_unsigned_field(dfr0, ID_AA64DFR0_EL1_TraceBuffer_SHIFT) && !(read_sysreg_s(SYS_TRBIDR_EL1) & TRBIDR_EL1_P)) - vcpu_set_flag(vcpu, DEBUG_STATE_SAVE_TRBE); -} - -void kvm_arch_vcpu_put_debug_state_flags(struct kvm_vcpu *vcpu) -{ - vcpu_clear_flag(vcpu, DEBUG_STATE_SAVE_SPE); - vcpu_clear_flag(vcpu, DEBUG_STATE_SAVE_TRBE); -} - -void kvm_init_host_debug_data(void) -{ - u64 dfr0 = read_sysreg(id_aa64dfr0_el1); - - if (cpuid_feature_extract_signed_field(dfr0, ID_AA64DFR0_EL1_PMUVer_SHIFT) > 0) - *host_data_ptr(nr_event_counters) = FIELD_GET(ARMV8_PMU_PMCR_N, - read_sysreg(pmcr_el0)); + host_data_set_flag(HAS_TRBE); } diff --git a/arch/arm64/kvm/hyp/nvhe/debug-sr.c b/arch/arm64/kvm/hyp/nvhe/debug-sr.c index 1e2a26d0196e..858bb38e273f 100644 --- a/arch/arm64/kvm/hyp/nvhe/debug-sr.c +++ b/arch/arm64/kvm/hyp/nvhe/debug-sr.c @@ -82,10 +82,10 @@ static void __debug_restore_trace(u64 trfcr_el1) void __debug_save_host_buffers_nvhe(struct kvm_vcpu *vcpu) { /* Disable and flush SPE data generation */ - if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_SPE)) + if (host_data_test_flag(HAS_SPE)) __debug_save_spe(host_data_ptr(host_debug_state.pmscr_el1)); /* Disable and flush Self-Hosted Trace generation */ - if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_TRBE)) + if (host_data_test_flag(HAS_TRBE)) __debug_save_trace(host_data_ptr(host_debug_state.trfcr_el1)); }
@@ -96,9 +96,9 @@ void __debug_switch_to_guest(struct kvm_vcpu *vcpu)
void __debug_restore_host_buffers_nvhe(struct kvm_vcpu *vcpu) { - if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_SPE)) + if (host_data_test_flag(HAS_SPE)) __debug_restore_spe(*host_data_ptr(host_debug_state.pmscr_el1)); - if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_TRBE)) + if (host_data_test_flag(HAS_TRBE)) __debug_restore_trace(*host_data_ptr(host_debug_state.trfcr_el1)); }