diff options
| author | Vincent Chen <vincent.chen@sifive.com> | 2023-06-05 14:07:16 +0300 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@rivosinc.com> | 2023-06-08 17:16:51 +0300 |
| commit | 0f4b82579716b12bb88257bd7ea80f25c791fb2c (patch) | |
| tree | 067c4d467c13e5cf20f552ca40aebcc861201c32 /arch/riscv/include/asm | |
| parent | bf78f1ea6e5108a7ebd55be0853f0716433117a9 (diff) | |
| download | linux-0f4b82579716b12bb88257bd7ea80f25c791fb2c.tar.xz | |
riscv: KVM: Add vector lazy save/restore support
This patch adds vector context save/restore for guest VCPUs. To reduce the
impact on KVM performance, the implementation imitates the FP context
switch mechanism to lazily store and restore the vector context only when
the kernel enters/exits the in-kernel run loop and not during the KVM
world switch.
Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
Signed-off-by: Andy Chiu <andy.chiu@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Acked-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20230605110724.21391-20-andy.chiu@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'arch/riscv/include/asm')
| -rw-r--r-- | arch/riscv/include/asm/kvm_host.h | 2 | ||||
| -rw-r--r-- | arch/riscv/include/asm/kvm_vcpu_vector.h | 82 |
2 files changed, 84 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/kvm_host.h b/arch/riscv/include/asm/kvm_host.h index ee0acccb1d3b..bd47a1dc2ff8 100644 --- a/arch/riscv/include/asm/kvm_host.h +++ b/arch/riscv/include/asm/kvm_host.h @@ -15,6 +15,7 @@ #include <linux/spinlock.h> #include <asm/hwcap.h> #include <asm/kvm_aia.h> +#include <asm/ptrace.h> #include <asm/kvm_vcpu_fp.h> #include <asm/kvm_vcpu_insn.h> #include <asm/kvm_vcpu_sbi.h> @@ -145,6 +146,7 @@ struct kvm_cpu_context { unsigned long sstatus; unsigned long hstatus; union __riscv_fp_state fp; + struct __riscv_v_ext_state vector; }; struct kvm_vcpu_csr { diff --git a/arch/riscv/include/asm/kvm_vcpu_vector.h b/arch/riscv/include/asm/kvm_vcpu_vector.h new file mode 100644 index 000000000000..ff994fdd6d0d --- /dev/null +++ b/arch/riscv/include/asm/kvm_vcpu_vector.h @@ -0,0 +1,82 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2022 SiFive + * + * Authors: + * Vincent Chen <vincent.chen@sifive.com> + * Greentime Hu <greentime.hu@sifive.com> + */ + +#ifndef __KVM_VCPU_RISCV_VECTOR_H +#define __KVM_VCPU_RISCV_VECTOR_H + +#include <linux/types.h> + +#ifdef CONFIG_RISCV_ISA_V +#include <asm/vector.h> +#include <asm/kvm_host.h> + +static __always_inline void __kvm_riscv_vector_save(struct kvm_cpu_context *context) +{ + __riscv_v_vstate_save(&context->vector, context->vector.datap); +} + +static __always_inline void __kvm_riscv_vector_restore(struct kvm_cpu_context *context) +{ + __riscv_v_vstate_restore(&context->vector, context->vector.datap); +} + +void kvm_riscv_vcpu_vector_reset(struct kvm_vcpu *vcpu); +void kvm_riscv_vcpu_guest_vector_save(struct kvm_cpu_context *cntx, + unsigned long *isa); +void kvm_riscv_vcpu_guest_vector_restore(struct kvm_cpu_context *cntx, + unsigned long *isa); +void kvm_riscv_vcpu_host_vector_save(struct kvm_cpu_context *cntx); +void kvm_riscv_vcpu_host_vector_restore(struct kvm_cpu_context *cntx); +int kvm_riscv_vcpu_alloc_vector_context(struct kvm_vcpu *vcpu, + struct kvm_cpu_context *cntx); +void kvm_riscv_vcpu_free_vector_context(struct kvm_vcpu *vcpu); +#else + +struct kvm_cpu_context; + +static inline void kvm_riscv_vcpu_vector_reset(struct kvm_vcpu *vcpu) +{ +} + +static inline void kvm_riscv_vcpu_guest_vector_save(struct kvm_cpu_context *cntx, + unsigned long *isa) +{ +} + +static inline void kvm_riscv_vcpu_guest_vector_restore(struct kvm_cpu_context *cntx, + unsigned long *isa) +{ +} + +static inline void kvm_riscv_vcpu_host_vector_save(struct kvm_cpu_context *cntx) +{ +} + +static inline void kvm_riscv_vcpu_host_vector_restore(struct kvm_cpu_context *cntx) +{ +} + +static inline int kvm_riscv_vcpu_alloc_vector_context(struct kvm_vcpu *vcpu, + struct kvm_cpu_context *cntx) +{ + return 0; +} + +static inline void kvm_riscv_vcpu_free_vector_context(struct kvm_vcpu *vcpu) +{ +} +#endif + +int kvm_riscv_vcpu_get_reg_vector(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg, + unsigned long rtype); +int kvm_riscv_vcpu_set_reg_vector(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg, + unsigned long rtype); +#endif |