The SCOUNTEREN CSR need not be saved/restored in the low-level __kvm_riscv_switch_to() function hence move the SCOUNTEREN CSR save/restore to the kvm_riscv_vcpu_swap_in_guest_state() and kvm_riscv_vcpu_swap_in_host_state() functions in C sources. Also, re-arrange the CSR save/restore and related GPR usage in the low-level __kvm_riscv_switch_to() low-level function. Signed-off-by: Anup Patel <apatel@xxxxxxxxxxxxxxxx> --- arch/riscv/kvm/vcpu.c | 2 ++ arch/riscv/kvm/vcpu_switch.S | 52 +++++++++++++++--------------------- 2 files changed, 23 insertions(+), 31 deletions(-) diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c index 93b1ce043482..957e1a5e081b 100644 --- a/arch/riscv/kvm/vcpu.c +++ b/arch/riscv/kvm/vcpu.c @@ -691,6 +691,7 @@ static __always_inline void kvm_riscv_vcpu_swap_in_guest_state(struct kvm_vcpu * struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; struct kvm_vcpu_config *cfg = &vcpu->arch.cfg; + vcpu->arch.host_scounteren = csr_swap(CSR_SCOUNTEREN, csr->scounteren); vcpu->arch.host_senvcfg = csr_swap(CSR_SENVCFG, csr->senvcfg); if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SMSTATEEN) && (cfg->hstateen0 & SMSTATEEN0_SSTATEEN0)) @@ -704,6 +705,7 @@ static __always_inline void kvm_riscv_vcpu_swap_in_host_state(struct kvm_vcpu *v struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; struct kvm_vcpu_config *cfg = &vcpu->arch.cfg; + csr->scounteren = csr_swap(CSR_SCOUNTEREN, vcpu->arch.host_scounteren); csr->senvcfg = csr_swap(CSR_SENVCFG, vcpu->arch.host_senvcfg); if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SMSTATEEN) && (cfg->hstateen0 & SMSTATEEN0_SSTATEEN0)) diff --git a/arch/riscv/kvm/vcpu_switch.S b/arch/riscv/kvm/vcpu_switch.S index f83643c4fdb9..3f8cbc21a644 100644 --- a/arch/riscv/kvm/vcpu_switch.S +++ b/arch/riscv/kvm/vcpu_switch.S @@ -43,30 +43,25 @@ SYM_FUNC_START(__kvm_riscv_switch_to) /* Load Guest CSR values */ REG_L t0, (KVM_ARCH_GUEST_SSTATUS)(a0) - REG_L t1, (KVM_ARCH_GUEST_SCOUNTEREN)(a0) - la t3, .Lkvm_switch_return - REG_L t4, (KVM_ARCH_GUEST_SEPC)(a0) + la t1, .Lkvm_switch_return + REG_L t2, (KVM_ARCH_GUEST_SEPC)(a0) /* Save Host and Restore Guest SSTATUS */ csrrw t0, CSR_SSTATUS, t0 - /* Save Host and Restore Guest SCOUNTEREN */ - csrrw t1, CSR_SCOUNTEREN, t1 - /* Save Host STVEC and change it to return path */ - csrrw t3, CSR_STVEC, t3 - - /* Save Host SSCRATCH and change it to struct kvm_vcpu_arch pointer */ - csrrw t2, CSR_SSCRATCH, a0 + csrrw t1, CSR_STVEC, t1 /* Restore Guest SEPC */ - csrw CSR_SEPC, t4 + csrw CSR_SEPC, t2 + + /* Save Host SSCRATCH and change it to struct kvm_vcpu_arch pointer */ + csrrw t3, CSR_SSCRATCH, a0 /* Store Host CSR values */ REG_S t0, (KVM_ARCH_HOST_SSTATUS)(a0) - REG_S t1, (KVM_ARCH_HOST_SCOUNTEREN)(a0) - REG_S t2, (KVM_ARCH_HOST_SSCRATCH)(a0) - REG_S t3, (KVM_ARCH_HOST_STVEC)(a0) + REG_S t1, (KVM_ARCH_HOST_STVEC)(a0) + REG_S t3, (KVM_ARCH_HOST_SSCRATCH)(a0) /* Restore Guest GPRs (except A0) */ REG_L ra, (KVM_ARCH_GUEST_RA)(a0) @@ -145,31 +140,26 @@ SYM_FUNC_START(__kvm_riscv_switch_to) REG_S t6, (KVM_ARCH_GUEST_T6)(a0) /* Load Host CSR values */ - REG_L t1, (KVM_ARCH_HOST_STVEC)(a0) - REG_L t2, (KVM_ARCH_HOST_SSCRATCH)(a0) - REG_L t3, (KVM_ARCH_HOST_SCOUNTEREN)(a0) - REG_L t4, (KVM_ARCH_HOST_SSTATUS)(a0) - - /* Save Guest SEPC */ - csrr t0, CSR_SEPC + REG_L t0, (KVM_ARCH_HOST_STVEC)(a0) + REG_L t1, (KVM_ARCH_HOST_SSCRATCH)(a0) + REG_L t2, (KVM_ARCH_HOST_SSTATUS)(a0) /* Save Guest A0 and Restore Host SSCRATCH */ - csrrw t2, CSR_SSCRATCH, t2 + csrrw t1, CSR_SSCRATCH, t1 - /* Restore Host STVEC */ - csrw CSR_STVEC, t1 + /* Save Guest SEPC */ + csrr t3, CSR_SEPC - /* Save Guest and Restore Host SCOUNTEREN */ - csrrw t3, CSR_SCOUNTEREN, t3 + /* Restore Host STVEC */ + csrw CSR_STVEC, t0 /* Save Guest and Restore Host SSTATUS */ - csrrw t4, CSR_SSTATUS, t4 + csrrw t2, CSR_SSTATUS, t2 /* Store Guest CSR values */ - REG_S t0, (KVM_ARCH_GUEST_SEPC)(a0) - REG_S t2, (KVM_ARCH_GUEST_A0)(a0) - REG_S t3, (KVM_ARCH_GUEST_SCOUNTEREN)(a0) - REG_S t4, (KVM_ARCH_GUEST_SSTATUS)(a0) + REG_S t1, (KVM_ARCH_GUEST_A0)(a0) + REG_S t2, (KVM_ARCH_GUEST_SSTATUS)(a0) + REG_S t3, (KVM_ARCH_GUEST_SEPC)(a0) /* Restore Host GPRs (except A0 and T0-T6) */ REG_L ra, (KVM_ARCH_HOST_RA)(a0) -- 2.34.1
