| Message ID | 20230127182558.2416400-5-atishp@rivosinc.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | KVM perf support | expand |
On Fri, Jan 27, 2023 at 11:56 PM Atish Patra <atishp@rivosinc.com> wrote: > > Currently the probe function just checks if an SBI extension is > registered or not. However, the extension may not want to advertise > itself depending on some other condition. > An additional extension specific probe function will allow > extensions to decide if they want to be advertised to the caller or > not. Any extension that does not require additional dependency checks > can avoid implementing this function. > > Signed-off-by: Atish Patra <atishp@rivosinc.com> Looks good to me. Reviewed-by: Anup Patel <anup@brainfault.org> Regards, Anup > --- > arch/riscv/include/asm/kvm_vcpu_sbi.h | 3 +++ > arch/riscv/kvm/vcpu_sbi_base.c | 13 +++++++++++-- > 2 files changed, 14 insertions(+), 2 deletions(-) > > diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi.h b/arch/riscv/include/asm/kvm_vcpu_sbi.h > index f79478a..45ba341 100644 > --- a/arch/riscv/include/asm/kvm_vcpu_sbi.h > +++ b/arch/riscv/include/asm/kvm_vcpu_sbi.h > @@ -29,6 +29,9 @@ struct kvm_vcpu_sbi_extension { > int (*handler)(struct kvm_vcpu *vcpu, struct kvm_run *run, > unsigned long *out_val, struct kvm_cpu_trap *utrap, > bool *exit); > + > + /* Extension specific probe function */ > + unsigned long (*probe)(struct kvm_vcpu *vcpu); > }; > > void kvm_riscv_vcpu_sbi_forward(struct kvm_vcpu *vcpu, struct kvm_run *run); > diff --git a/arch/riscv/kvm/vcpu_sbi_base.c b/arch/riscv/kvm/vcpu_sbi_base.c > index 5d65c63..846d518 100644 > --- a/arch/riscv/kvm/vcpu_sbi_base.c > +++ b/arch/riscv/kvm/vcpu_sbi_base.c > @@ -19,6 +19,7 @@ static int kvm_sbi_ext_base_handler(struct kvm_vcpu *vcpu, struct kvm_run *run, > { > int ret = 0; > struct kvm_cpu_context *cp = &vcpu->arch.guest_context; > + const struct kvm_vcpu_sbi_extension *sbi_ext; > > switch (cp->a6) { > case SBI_EXT_BASE_GET_SPEC_VERSION: > @@ -43,8 +44,16 @@ static int kvm_sbi_ext_base_handler(struct kvm_vcpu *vcpu, struct kvm_run *run, > */ > kvm_riscv_vcpu_sbi_forward(vcpu, run); > *exit = true; > - } else > - *out_val = kvm_vcpu_sbi_find_ext(cp->a0) ? 1 : 0; > + } else { > + sbi_ext = kvm_vcpu_sbi_find_ext(cp->a0); > + if (sbi_ext) { > + if (sbi_ext->probe) > + *out_val = sbi_ext->probe(vcpu); > + else > + *out_val = 1; > + } else > + *out_val = 0; > + } > break; > case SBI_EXT_BASE_GET_MVENDORID: > *out_val = vcpu->arch.mvendorid; > -- > 2.25.1 >
diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi.h b/arch/riscv/include/asm/kvm_vcpu_sbi.h index f79478a..45ba341 100644 --- a/arch/riscv/include/asm/kvm_vcpu_sbi.h +++ b/arch/riscv/include/asm/kvm_vcpu_sbi.h @@ -29,6 +29,9 @@ struct kvm_vcpu_sbi_extension { int (*handler)(struct kvm_vcpu *vcpu, struct kvm_run *run, unsigned long *out_val, struct kvm_cpu_trap *utrap, bool *exit); + + /* Extension specific probe function */ + unsigned long (*probe)(struct kvm_vcpu *vcpu); }; void kvm_riscv_vcpu_sbi_forward(struct kvm_vcpu *vcpu, struct kvm_run *run); diff --git a/arch/riscv/kvm/vcpu_sbi_base.c b/arch/riscv/kvm/vcpu_sbi_base.c index 5d65c63..846d518 100644 --- a/arch/riscv/kvm/vcpu_sbi_base.c +++ b/arch/riscv/kvm/vcpu_sbi_base.c @@ -19,6 +19,7 @@ static int kvm_sbi_ext_base_handler(struct kvm_vcpu *vcpu, struct kvm_run *run, { int ret = 0; struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + const struct kvm_vcpu_sbi_extension *sbi_ext; switch (cp->a6) { case SBI_EXT_BASE_GET_SPEC_VERSION: @@ -43,8 +44,16 @@ static int kvm_sbi_ext_base_handler(struct kvm_vcpu *vcpu, struct kvm_run *run, */ kvm_riscv_vcpu_sbi_forward(vcpu, run); *exit = true; - } else - *out_val = kvm_vcpu_sbi_find_ext(cp->a0) ? 1 : 0; + } else { + sbi_ext = kvm_vcpu_sbi_find_ext(cp->a0); + if (sbi_ext) { + if (sbi_ext->probe) + *out_val = sbi_ext->probe(vcpu); + else + *out_val = 1; + } else + *out_val = 0; + } break; case SBI_EXT_BASE_GET_MVENDORID: *out_val = vcpu->arch.mvendorid;
Currently the probe function just checks if an SBI extension is registered or not. However, the extension may not want to advertise itself depending on some other condition. An additional extension specific probe function will allow extensions to decide if they want to be advertised to the caller or not. Any extension that does not require additional dependency checks can avoid implementing this function. Signed-off-by: Atish Patra <atishp@rivosinc.com> --- arch/riscv/include/asm/kvm_vcpu_sbi.h | 3 +++ arch/riscv/kvm/vcpu_sbi_base.c | 13 +++++++++++-- 2 files changed, 14 insertions(+), 2 deletions(-)