| Message ID | 20221215170046.2010255-3-atishp@rivosinc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM perf support | expand |
On Thu, Dec 15, 2022 at 09:00:37AM -0800, Atish Patra 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> > --- > 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..61dac1b 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, unsigned long extid); It doesn't seem like the extid parameter should be necessary since the probe function is specific to the extension, but it doesn't hurt either. > }; > > 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..89e2415 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, cp->a0); > + else > + *out_val = 1; > + } else > + *out_val = 0; > + } > break; > case SBI_EXT_BASE_GET_MVENDORID: > *out_val = vcpu->arch.mvendorid; > -- > 2.25.1 > Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
On Thu, Jan 12, 2023 at 2:21 AM Andrew Jones <ajones@ventanamicro.com> wrote: > > On Thu, Dec 15, 2022 at 09:00:37AM -0800, Atish Patra 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> > > --- > > 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..61dac1b 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, unsigned long extid); > > It doesn't seem like the extid parameter should be necessary since the > probe function is specific to the extension, but it doesn't hurt either. > Yeah. You are correct. I will drop it. Thanks. > > }; > > > > 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..89e2415 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, cp->a0); > > + else > > + *out_val = 1; > > + } else > > + *out_val = 0; > > + } > > break; > > case SBI_EXT_BASE_GET_MVENDORID: > > *out_val = vcpu->arch.mvendorid; > > -- > > 2.25.1 > > > > Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi.h b/arch/riscv/include/asm/kvm_vcpu_sbi.h index f79478a..61dac1b 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, unsigned long extid); }; 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..89e2415 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, cp->a0); + 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(-)