Re: [PATCH 11/20] target/riscv: introduce KVM AccelCPUClass

[Andrew Jones <ajones@ventanamicro.com>]

On Fri, Aug 25, 2023 at 10:08:44AM -0300, Daniel Henrique Barboza wrote:
> Add a KVM accelerator class like we did with TCG. The difference is
> that, at least for now, we won't be using a realize() implementation for
> this accelerator.
> 
> We'll start by assiging kvm_riscv_cpu_add_kvm_properties(), renamed to
> kvm_cpu_instance_init(), as a 'cpu_instance_init' implementation. Change
> riscv_cpu_post_init() to invoke accel_cpu_instance_init(), which will go
> through the 'cpu_instance_init' impl of the current acceleration (if
> available) and execute it. The end result is that the KVM initial setup,
> i.e. starting registers and adding its specific properties, will be done
> via this hook.
> 
> riscv_cpu_add_user_properties() is still being called via the common
> post_init() function, thus we still need the "if kvm then return" logic
> inside it for now. We'll deal with it when TCG accel class get its own
> 'cpu_instance_init' implementation.
> 
> riscv_add_satp_mode_properties() is now being exported from cpu.c since
> it's a common helper between KVM and TCG.
> 
> Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
> ---
>  target/riscv/cpu.c       |  8 ++---
>  target/riscv/cpu.h       |  1 +
>  target/riscv/kvm.c       | 64 +++++++++++++++++++++++++++-------------
>  target/riscv/kvm_riscv.h |  1 -
>  4 files changed, 49 insertions(+), 25 deletions(-)
> 
> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> index 58b0ef2af8..04c6bfaeef 100644
> --- a/target/riscv/cpu.c
> +++ b/target/riscv/cpu.c
> @@ -1112,7 +1112,7 @@ static void cpu_riscv_set_satp(Object *obj, Visitor *v, const char *name,
>      satp_map->init |= 1 << satp;
>  }
>  
> -static void riscv_add_satp_mode_properties(Object *obj)
> +void riscv_add_satp_mode_properties(Object *obj)
>  {
>      RISCVCPU *cpu = RISCV_CPU(obj);
>  
> @@ -1199,6 +1199,8 @@ static void riscv_cpu_post_init(Object *obj)
>      RISCVCPU *cpu = RISCV_CPU(obj);
>      RISCVCPUClass *rcc = RISCV_CPU_GET_CLASS(cpu);
>  
> +    accel_cpu_instance_init(CPU(obj));
> +
>      if (rcc->user_extension_properties) {
>          riscv_cpu_add_user_properties(obj);
>      }
> @@ -1561,12 +1563,10 @@ static void riscv_cpu_add_multiext_prop_array(Object *obj,
>  static void riscv_cpu_add_user_properties(Object *obj)
>  {
>  #ifndef CONFIG_USER_ONLY
> -    riscv_add_satp_mode_properties(obj);
> -
>      if (kvm_enabled()) {
> -        kvm_riscv_cpu_add_kvm_properties(obj);
>          return;
>      }
> +    riscv_add_satp_mode_properties(obj);
>  #endif
>  
>      riscv_cpu_add_misa_properties(obj);
> diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
> index b9c4bea3f7..950c2301f2 100644
> --- a/target/riscv/cpu.h
> +++ b/target/riscv/cpu.h
> @@ -726,6 +726,7 @@ extern const RISCVCPUMultiExtConfig riscv_cpu_experimental_exts[];
>  extern Property riscv_cpu_options[];
>  
>  void riscv_cpu_add_misa_properties(Object *cpu_obj);
> +void riscv_add_satp_mode_properties(Object *obj);
>  
>  /* CSR function table */
>  extern riscv_csr_operations csr_ops[CSR_TABLE_SIZE];
> diff --git a/target/riscv/kvm.c b/target/riscv/kvm.c
> index 7e67121456..3c4fa43cee 100644
> --- a/target/riscv/kvm.c
> +++ b/target/riscv/kvm.c
> @@ -31,6 +31,7 @@
>  #include "sysemu/kvm_int.h"
>  #include "cpu.h"
>  #include "trace.h"
> +#include "hw/core/accel-cpu.h"
>  #include "hw/pci/pci.h"
>  #include "exec/memattrs.h"
>  #include "exec/address-spaces.h"
> @@ -1262,26 +1263,6 @@ void kvm_riscv_aia_create(MachineState *machine, uint64_t group_shift,
>      kvm_msi_via_irqfd_allowed = kvm_irqfds_enabled();
>  }
>  
> -void kvm_riscv_cpu_add_kvm_properties(Object *obj)
> -{
> -    DeviceState *dev = DEVICE(obj);
> -
> -    riscv_init_user_properties(obj);
> -    riscv_cpu_add_misa_properties(obj);
> -
> -    riscv_cpu_add_kvm_unavail_prop_array(obj, riscv_cpu_extensions);
> -    riscv_cpu_add_kvm_unavail_prop_array(obj, riscv_cpu_vendor_exts);
> -    riscv_cpu_add_kvm_unavail_prop_array(obj, riscv_cpu_experimental_exts);
> -
> -    for (Property *prop = riscv_cpu_options; prop && prop->name; prop++) {
> -        /* Check if KVM created the property already */
> -        if (object_property_find(obj, prop->name)) {
> -            continue;
> -        }
> -        qdev_property_add_static(dev, prop);
> -    }
> -}
> -
>  static void riscv_host_cpu_init(Object *obj)
>  {
>      CPURISCVState *env = &RISCV_CPU(obj)->env;
> @@ -1310,3 +1291,46 @@ static const TypeInfo riscv_kvm_cpu_type_infos[] = {
>  };
>  
>  DEFINE_TYPES(riscv_kvm_cpu_type_infos)
> +
> +static void kvm_cpu_instance_init(CPUState *cs)
> +{
> +    Object *obj = OBJECT(RISCV_CPU(cs));
> +    DeviceState *dev = DEVICE(obj);
> +
> +    riscv_init_user_properties(obj);
> +
> +    riscv_add_satp_mode_properties(obj);
> +    riscv_cpu_add_misa_properties(obj);
> +
> +    riscv_cpu_add_kvm_unavail_prop_array(obj, riscv_cpu_extensions);
> +    riscv_cpu_add_kvm_unavail_prop_array(obj, riscv_cpu_vendor_exts);
> +    riscv_cpu_add_kvm_unavail_prop_array(obj, riscv_cpu_experimental_exts);
> +
> +    for (Property *prop = riscv_cpu_options; prop && prop->name; prop++) {
> +        /* Check if we have a specific KVM handler for the option */
> +        if (object_property_find(obj, prop->name)) {
> +            continue;
> +        }
> +        qdev_property_add_static(dev, prop);
> +    }
> +}
> +
> +static void kvm_cpu_accel_class_init(ObjectClass *oc, void *data)
> +{
> +    AccelCPUClass *acc = ACCEL_CPU_CLASS(oc);
> +
> +    acc->cpu_instance_init = kvm_cpu_instance_init;
> +}
> +
> +static const TypeInfo kvm_cpu_accel_type_info = {
> +    .name = ACCEL_CPU_NAME("kvm"),
> +
> +    .parent = TYPE_ACCEL_CPU,
> +    .class_init = kvm_cpu_accel_class_init,
> +    .abstract = true,
> +};

blank line here

> +static void kvm_cpu_accel_register_types(void)
> +{
> +    type_register_static(&kvm_cpu_accel_type_info);
> +}
> +type_init(kvm_cpu_accel_register_types);
> diff --git a/target/riscv/kvm_riscv.h b/target/riscv/kvm_riscv.h
> index 81e08b8359..a0ea1a7505 100644
> --- a/target/riscv/kvm_riscv.h
> +++ b/target/riscv/kvm_riscv.h
> @@ -19,7 +19,6 @@
>  #ifndef QEMU_KVM_RISCV_H
>  #define QEMU_KVM_RISCV_H
>  
> -void kvm_riscv_cpu_add_kvm_properties(Object *obj);
>  void kvm_riscv_reset_vcpu(RISCVCPU *cpu);
>  void kvm_riscv_set_irq(RISCVCPU *cpu, int irq, int level);
>  void kvm_riscv_aia_create(MachineState *machine, uint64_t group_shift,
> -- 
> 2.41.0
> 
>

I'll wait for v2 to complete the review of this one.

Thanks,
drew