[PATCH v2 3/6] arm64: KVM: Move SPE and trace registers to the sysreg array
Suzuki K Poulose
suzuki.poulose at arm.com
Thu Oct 5 09:48:54 PDT 2023
On 05/10/2023 13:57, James Clark wrote:
> pmscr_el1 and trfcr_el1 are currently special cased in the
> host_debug_state struct, but they're just registers after all so give
> them entries in the sysreg array and refer to them through the host
> context.
>
> Signed-off-by: James Clark <james.clark at arm.com>
Looks good to me.
Reviewed-by: Suzuki K Poulose <suzuki.poulose at arm.com>
> ---
> arch/arm64/include/asm/kvm_host.h | 6 ++--
> arch/arm64/include/asm/kvm_hyp.h | 4 +--
> arch/arm64/kvm/hyp/nvhe/debug-sr.c | 44 +++++++++++++++---------------
> arch/arm64/kvm/hyp/nvhe/switch.c | 4 +--
> 4 files changed, 28 insertions(+), 30 deletions(-)
>
> diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
> index e36f7e8a76ce..b5200f199692 100644
> --- a/arch/arm64/include/asm/kvm_host.h
> +++ b/arch/arm64/include/asm/kvm_host.h
> @@ -439,6 +439,8 @@ enum vcpu_sysreg {
> CNTHP_CVAL_EL2,
> CNTHV_CTL_EL2,
> CNTHV_CVAL_EL2,
> + PMSCR_EL1, /* Statistical profiling extension */
> + TRFCR_EL1, /* Self-hosted trace filters */
>
> NR_SYS_REGS /* Nothing after this line! */
> };
> @@ -572,10 +574,6 @@ struct kvm_vcpu_arch {
> struct {
> /* {Break,watch}point registers */
> struct kvm_guest_debug_arch regs;
> - /* Statistical profiling extension */
> - u64 pmscr_el1;
> - /* Self-hosted trace */
> - u64 trfcr_el1;
> } host_debug_state;
>
> /* VGIC state */
> diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h
> index b7238c72a04c..37e238f526d7 100644
> --- a/arch/arm64/include/asm/kvm_hyp.h
> +++ b/arch/arm64/include/asm/kvm_hyp.h
> @@ -103,8 +103,8 @@ void __debug_switch_to_guest(struct kvm_vcpu *vcpu);
> void __debug_switch_to_host(struct kvm_vcpu *vcpu);
>
> #ifdef __KVM_NVHE_HYPERVISOR__
> -void __debug_save_host_buffers_nvhe(struct kvm_vcpu *vcpu);
> -void __debug_restore_host_buffers_nvhe(struct kvm_vcpu *vcpu);
> +void __debug_save_host_buffers_nvhe(struct kvm_cpu_context *host_ctxt);
> +void __debug_restore_host_buffers_nvhe(struct kvm_cpu_context *host_ctxt);
> #endif
>
> void __fpsimd_save_state(struct user_fpsimd_state *fp_regs);
> diff --git a/arch/arm64/kvm/hyp/nvhe/debug-sr.c b/arch/arm64/kvm/hyp/nvhe/debug-sr.c
> index 89c208112eb7..128a57dddabf 100644
> --- a/arch/arm64/kvm/hyp/nvhe/debug-sr.c
> +++ b/arch/arm64/kvm/hyp/nvhe/debug-sr.c
> @@ -14,12 +14,12 @@
> #include <asm/kvm_hyp.h>
> #include <asm/kvm_mmu.h>
>
> -static void __debug_save_spe(u64 *pmscr_el1)
> +static void __debug_save_spe(struct kvm_cpu_context *host_ctxt)
> {
> u64 reg;
>
> /* Clear pmscr in case of early return */
> - *pmscr_el1 = 0;
> + ctxt_sys_reg(host_ctxt, PMSCR_EL1) = 0;
>
> /*
> * At this point, we know that this CPU implements
> @@ -31,7 +31,7 @@ static void __debug_save_spe(u64 *pmscr_el1)
> return;
>
> /* Yes; save the control register and disable data generation */
> - *pmscr_el1 = read_sysreg_s(SYS_PMSCR_EL1);
> + ctxt_sys_reg(host_ctxt, PMSCR_EL1) = read_sysreg_s(SYS_PMSCR_EL1);
> write_sysreg_s(0, SYS_PMSCR_EL1);
> isb();
>
> @@ -39,21 +39,21 @@ static void __debug_save_spe(u64 *pmscr_el1)
> psb_csync();
> }
>
> -static void __debug_restore_spe(u64 pmscr_el1)
> +static void __debug_restore_spe(struct kvm_cpu_context *host_ctxt)
> {
> - if (!pmscr_el1)
> + if (!ctxt_sys_reg(host_ctxt, PMSCR_EL1))
> return;
>
> /* The host page table is installed, but not yet synchronised */
> isb();
>
> /* Re-enable data generation */
> - write_sysreg_s(pmscr_el1, SYS_PMSCR_EL1);
> + write_sysreg_s(ctxt_sys_reg(host_ctxt, PMSCR_EL1), SYS_PMSCR_EL1);
> }
>
> -static void __debug_save_trace(u64 *trfcr_el1)
> +static void __debug_save_trace(struct kvm_cpu_context *host_ctxt)
> {
> - *trfcr_el1 = 0;
> + ctxt_sys_reg(host_ctxt, TRFCR_EL1) = 0;
>
> /* Check if the TRBE is enabled */
> if (!(read_sysreg_s(SYS_TRBLIMITR_EL1) & TRBLIMITR_EL1_E))
> @@ -63,30 +63,30 @@ static void __debug_save_trace(u64 *trfcr_el1)
> * Since access to TRFCR_EL1 is trapped, the guest can't
> * modify the filtering set by the host.
> */
> - *trfcr_el1 = read_sysreg_s(SYS_TRFCR_EL1);
> + ctxt_sys_reg(host_ctxt, TRFCR_EL1) = read_sysreg_s(SYS_TRFCR_EL1);
> write_sysreg_s(0, SYS_TRFCR_EL1);
> isb();
> /* Drain the trace buffer to memory */
> tsb_csync();
> }
>
> -static void __debug_restore_trace(u64 trfcr_el1)
> +static void __debug_restore_trace(struct kvm_cpu_context *host_ctxt)
> {
> - if (!trfcr_el1)
> + if (!ctxt_sys_reg(host_ctxt, TRFCR_EL1))
> return;
>
> /* Restore trace filter controls */
> - write_sysreg_s(trfcr_el1, SYS_TRFCR_EL1);
> + write_sysreg_s(ctxt_sys_reg(host_ctxt, TRFCR_EL1), SYS_TRFCR_EL1);
> }
>
> -void __debug_save_host_buffers_nvhe(struct kvm_vcpu *vcpu)
> +void __debug_save_host_buffers_nvhe(struct kvm_cpu_context *host_ctxt)
> {
> /* Disable and flush SPE data generation */
> - if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_SPE))
> - __debug_save_spe(&vcpu->arch.host_debug_state.pmscr_el1);
> + if (vcpu_get_flag(host_ctxt->__hyp_running_vcpu, DEBUG_STATE_SAVE_SPE))
> + __debug_save_spe(host_ctxt);
> /* Disable and flush Self-Hosted Trace generation */
> - if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_TRFCR))
> - __debug_save_trace(&vcpu->arch.host_debug_state.trfcr_el1);
> + if (vcpu_get_flag(host_ctxt->__hyp_running_vcpu, DEBUG_STATE_SAVE_TRFCR))
> + __debug_save_trace(host_ctxt);
> }
>
> void __debug_switch_to_guest(struct kvm_vcpu *vcpu)
> @@ -94,12 +94,12 @@ void __debug_switch_to_guest(struct kvm_vcpu *vcpu)
> __debug_switch_to_guest_common(vcpu);
> }
>
> -void __debug_restore_host_buffers_nvhe(struct kvm_vcpu *vcpu)
> +void __debug_restore_host_buffers_nvhe(struct kvm_cpu_context *host_ctxt)
> {
> - if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_SPE))
> - __debug_restore_spe(vcpu->arch.host_debug_state.pmscr_el1);
> - if (vcpu_get_flag(vcpu, DEBUG_STATE_SAVE_TRFCR))
> - __debug_restore_trace(vcpu->arch.host_debug_state.trfcr_el1);
> + if (vcpu_get_flag(host_ctxt->__hyp_running_vcpu, DEBUG_STATE_SAVE_SPE))
> + __debug_restore_spe(host_ctxt);
> + if (vcpu_get_flag(host_ctxt->__hyp_running_vcpu, DEBUG_STATE_SAVE_TRFCR))
> + __debug_restore_trace(host_ctxt);
> }
>
> void __debug_switch_to_host(struct kvm_vcpu *vcpu)
> diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c
> index c353a06ee7e6..c8f15e4dab19 100644
> --- a/arch/arm64/kvm/hyp/nvhe/switch.c
> +++ b/arch/arm64/kvm/hyp/nvhe/switch.c
> @@ -276,7 +276,7 @@ int __kvm_vcpu_run(struct kvm_vcpu *vcpu)
> * translation regime to EL2 (via MDCR_EL2_E2PB == 0) and
> * before we load guest Stage1.
> */
> - __debug_save_host_buffers_nvhe(vcpu);
> + __debug_save_host_buffers_nvhe(host_ctxt);
>
> /*
> * We're about to restore some new MMU state. Make sure
> @@ -343,7 +343,7 @@ int __kvm_vcpu_run(struct kvm_vcpu *vcpu)
> * This must come after restoring the host sysregs, since a non-VHE
> * system may enable SPE here and make use of the TTBRs.
> */
> - __debug_restore_host_buffers_nvhe(vcpu);
> + __debug_restore_host_buffers_nvhe(host_ctxt);
>
> if (pmu_switch_needed)
> __pmu_switch_to_host(vcpu);
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