diff options
author | Atish Patra <atish.patra@wdc.com> | 2021-09-27 14:40:12 +0300 |
---|---|---|
committer | Anup Patel <anup@brainfault.org> | 2021-10-04 13:38:23 +0300 |
commit | 5de52d4a23ad3346c3cb24aae728ef6642d1a92e (patch) | |
tree | 2e5e161bb93e0cecc740a8029a4d186ddb71ad27 /arch/riscv/kvm/vcpu_switch.S | |
parent | 3a9f66cb25e18a3eeca36c08d9f823a35b3ddc22 (diff) | |
download | linux-5de52d4a23ad3346c3cb24aae728ef6642d1a92e.tar.xz |
RISC-V: KVM: FP lazy save/restore
This patch adds floating point (F and D extension) context save/restore
for guest VCPUs. The FP context is saved and restored lazily only when
kernel enter/exits the in-kernel run loop and not during the KVM world
switch. This way FP save/restore has minimal impact on KVM performance.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alexander Graf <graf@amazon.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Diffstat (limited to 'arch/riscv/kvm/vcpu_switch.S')
-rw-r--r-- | arch/riscv/kvm/vcpu_switch.S | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/arch/riscv/kvm/vcpu_switch.S b/arch/riscv/kvm/vcpu_switch.S index e22721e1b892..029a28a195c6 100644 --- a/arch/riscv/kvm/vcpu_switch.S +++ b/arch/riscv/kvm/vcpu_switch.S @@ -224,3 +224,177 @@ ENTRY(__kvm_riscv_unpriv_trap) REG_S a1, (KVM_ARCH_TRAP_HTINST)(a0) sret ENDPROC(__kvm_riscv_unpriv_trap) + +#ifdef CONFIG_FPU + .align 3 + .global __kvm_riscv_fp_f_save +__kvm_riscv_fp_f_save: + csrr t2, CSR_SSTATUS + li t1, SR_FS + csrs CSR_SSTATUS, t1 + frcsr t0 + fsw f0, KVM_ARCH_FP_F_F0(a0) + fsw f1, KVM_ARCH_FP_F_F1(a0) + fsw f2, KVM_ARCH_FP_F_F2(a0) + fsw f3, KVM_ARCH_FP_F_F3(a0) + fsw f4, KVM_ARCH_FP_F_F4(a0) + fsw f5, KVM_ARCH_FP_F_F5(a0) + fsw f6, KVM_ARCH_FP_F_F6(a0) + fsw f7, KVM_ARCH_FP_F_F7(a0) + fsw f8, KVM_ARCH_FP_F_F8(a0) + fsw f9, KVM_ARCH_FP_F_F9(a0) + fsw f10, KVM_ARCH_FP_F_F10(a0) + fsw f11, KVM_ARCH_FP_F_F11(a0) + fsw f12, KVM_ARCH_FP_F_F12(a0) + fsw f13, KVM_ARCH_FP_F_F13(a0) + fsw f14, KVM_ARCH_FP_F_F14(a0) + fsw f15, KVM_ARCH_FP_F_F15(a0) + fsw f16, KVM_ARCH_FP_F_F16(a0) + fsw f17, KVM_ARCH_FP_F_F17(a0) + fsw f18, KVM_ARCH_FP_F_F18(a0) + fsw f19, KVM_ARCH_FP_F_F19(a0) + fsw f20, KVM_ARCH_FP_F_F20(a0) + fsw f21, KVM_ARCH_FP_F_F21(a0) + fsw f22, KVM_ARCH_FP_F_F22(a0) + fsw f23, KVM_ARCH_FP_F_F23(a0) + fsw f24, KVM_ARCH_FP_F_F24(a0) + fsw f25, KVM_ARCH_FP_F_F25(a0) + fsw f26, KVM_ARCH_FP_F_F26(a0) + fsw f27, KVM_ARCH_FP_F_F27(a0) + fsw f28, KVM_ARCH_FP_F_F28(a0) + fsw f29, KVM_ARCH_FP_F_F29(a0) + fsw f30, KVM_ARCH_FP_F_F30(a0) + fsw f31, KVM_ARCH_FP_F_F31(a0) + sw t0, KVM_ARCH_FP_F_FCSR(a0) + csrw CSR_SSTATUS, t2 + ret + + .align 3 + .global __kvm_riscv_fp_d_save +__kvm_riscv_fp_d_save: + csrr t2, CSR_SSTATUS + li t1, SR_FS + csrs CSR_SSTATUS, t1 + frcsr t0 + fsd f0, KVM_ARCH_FP_D_F0(a0) + fsd f1, KVM_ARCH_FP_D_F1(a0) + fsd f2, KVM_ARCH_FP_D_F2(a0) + fsd f3, KVM_ARCH_FP_D_F3(a0) + fsd f4, KVM_ARCH_FP_D_F4(a0) + fsd f5, KVM_ARCH_FP_D_F5(a0) + fsd f6, KVM_ARCH_FP_D_F6(a0) + fsd f7, KVM_ARCH_FP_D_F7(a0) + fsd f8, KVM_ARCH_FP_D_F8(a0) + fsd f9, KVM_ARCH_FP_D_F9(a0) + fsd f10, KVM_ARCH_FP_D_F10(a0) + fsd f11, KVM_ARCH_FP_D_F11(a0) + fsd f12, KVM_ARCH_FP_D_F12(a0) + fsd f13, KVM_ARCH_FP_D_F13(a0) + fsd f14, KVM_ARCH_FP_D_F14(a0) + fsd f15, KVM_ARCH_FP_D_F15(a0) + fsd f16, KVM_ARCH_FP_D_F16(a0) + fsd f17, KVM_ARCH_FP_D_F17(a0) + fsd f18, KVM_ARCH_FP_D_F18(a0) + fsd f19, KVM_ARCH_FP_D_F19(a0) + fsd f20, KVM_ARCH_FP_D_F20(a0) + fsd f21, KVM_ARCH_FP_D_F21(a0) + fsd f22, KVM_ARCH_FP_D_F22(a0) + fsd f23, KVM_ARCH_FP_D_F23(a0) + fsd f24, KVM_ARCH_FP_D_F24(a0) + fsd f25, KVM_ARCH_FP_D_F25(a0) + fsd f26, KVM_ARCH_FP_D_F26(a0) + fsd f27, KVM_ARCH_FP_D_F27(a0) + fsd f28, KVM_ARCH_FP_D_F28(a0) + fsd f29, KVM_ARCH_FP_D_F29(a0) + fsd f30, KVM_ARCH_FP_D_F30(a0) + fsd f31, KVM_ARCH_FP_D_F31(a0) + sw t0, KVM_ARCH_FP_D_FCSR(a0) + csrw CSR_SSTATUS, t2 + ret + + .align 3 + .global __kvm_riscv_fp_f_restore +__kvm_riscv_fp_f_restore: + csrr t2, CSR_SSTATUS + li t1, SR_FS + lw t0, KVM_ARCH_FP_F_FCSR(a0) + csrs CSR_SSTATUS, t1 + flw f0, KVM_ARCH_FP_F_F0(a0) + flw f1, KVM_ARCH_FP_F_F1(a0) + flw f2, KVM_ARCH_FP_F_F2(a0) + flw f3, KVM_ARCH_FP_F_F3(a0) + flw f4, KVM_ARCH_FP_F_F4(a0) + flw f5, KVM_ARCH_FP_F_F5(a0) + flw f6, KVM_ARCH_FP_F_F6(a0) + flw f7, KVM_ARCH_FP_F_F7(a0) + flw f8, KVM_ARCH_FP_F_F8(a0) + flw f9, KVM_ARCH_FP_F_F9(a0) + flw f10, KVM_ARCH_FP_F_F10(a0) + flw f11, KVM_ARCH_FP_F_F11(a0) + flw f12, KVM_ARCH_FP_F_F12(a0) + flw f13, KVM_ARCH_FP_F_F13(a0) + flw f14, KVM_ARCH_FP_F_F14(a0) + flw f15, KVM_ARCH_FP_F_F15(a0) + flw f16, KVM_ARCH_FP_F_F16(a0) + flw f17, KVM_ARCH_FP_F_F17(a0) + flw f18, KVM_ARCH_FP_F_F18(a0) + flw f19, KVM_ARCH_FP_F_F19(a0) + flw f20, KVM_ARCH_FP_F_F20(a0) + flw f21, KVM_ARCH_FP_F_F21(a0) + flw f22, KVM_ARCH_FP_F_F22(a0) + flw f23, KVM_ARCH_FP_F_F23(a0) + flw f24, KVM_ARCH_FP_F_F24(a0) + flw f25, KVM_ARCH_FP_F_F25(a0) + flw f26, KVM_ARCH_FP_F_F26(a0) + flw f27, KVM_ARCH_FP_F_F27(a0) + flw f28, KVM_ARCH_FP_F_F28(a0) + flw f29, KVM_ARCH_FP_F_F29(a0) + flw f30, KVM_ARCH_FP_F_F30(a0) + flw f31, KVM_ARCH_FP_F_F31(a0) + fscsr t0 + csrw CSR_SSTATUS, t2 + ret + + .align 3 + .global __kvm_riscv_fp_d_restore +__kvm_riscv_fp_d_restore: + csrr t2, CSR_SSTATUS + li t1, SR_FS + lw t0, KVM_ARCH_FP_D_FCSR(a0) + csrs CSR_SSTATUS, t1 + fld f0, KVM_ARCH_FP_D_F0(a0) + fld f1, KVM_ARCH_FP_D_F1(a0) + fld f2, KVM_ARCH_FP_D_F2(a0) + fld f3, KVM_ARCH_FP_D_F3(a0) + fld f4, KVM_ARCH_FP_D_F4(a0) + fld f5, KVM_ARCH_FP_D_F5(a0) + fld f6, KVM_ARCH_FP_D_F6(a0) + fld f7, KVM_ARCH_FP_D_F7(a0) + fld f8, KVM_ARCH_FP_D_F8(a0) + fld f9, KVM_ARCH_FP_D_F9(a0) + fld f10, KVM_ARCH_FP_D_F10(a0) + fld f11, KVM_ARCH_FP_D_F11(a0) + fld f12, KVM_ARCH_FP_D_F12(a0) + fld f13, KVM_ARCH_FP_D_F13(a0) + fld f14, KVM_ARCH_FP_D_F14(a0) + fld f15, KVM_ARCH_FP_D_F15(a0) + fld f16, KVM_ARCH_FP_D_F16(a0) + fld f17, KVM_ARCH_FP_D_F17(a0) + fld f18, KVM_ARCH_FP_D_F18(a0) + fld f19, KVM_ARCH_FP_D_F19(a0) + fld f20, KVM_ARCH_FP_D_F20(a0) + fld f21, KVM_ARCH_FP_D_F21(a0) + fld f22, KVM_ARCH_FP_D_F22(a0) + fld f23, KVM_ARCH_FP_D_F23(a0) + fld f24, KVM_ARCH_FP_D_F24(a0) + fld f25, KVM_ARCH_FP_D_F25(a0) + fld f26, KVM_ARCH_FP_D_F26(a0) + fld f27, KVM_ARCH_FP_D_F27(a0) + fld f28, KVM_ARCH_FP_D_F28(a0) + fld f29, KVM_ARCH_FP_D_F29(a0) + fld f30, KVM_ARCH_FP_D_F30(a0) + fld f31, KVM_ARCH_FP_D_F31(a0) + fscsr t0 + csrw CSR_SSTATUS, t2 + ret +#endif |