Re: [PULL 48/65] target/riscv/cpu.c: split kvm prop handling to its own helper

[Alistair Francis]

On Sun, Sep 10, 2023 at 6:58 PM Daniel Henrique Barboza
<dbarboza@ventanamicro.com> wrote:
>
>
>
> On 9/8/23 10:21, Philippe Mathieu-Daudé wrote:
> > On 8/9/23 08:04, Alistair Francis wrote:
> >> From: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
> >>
> >> Future patches will split the existing Property arrays even further, and
> >> the existing code in riscv_cpu_add_user_properties() will start to scale
> >> bad with it because it's dealing with KVM constraints mixed in with TCG
> >> constraints. We're going to pay a high price to share a couple of common
> >> lines of code between the two.
> >>
> >> Create a new riscv_cpu_add_kvm_properties() that will be forked from
> >> riscv_cpu_add_user_properties() if we're running KVM. The helper
> >> includes all properties that a KVM CPU will add. The rest of
> >> riscv_cpu_add_user_properties() body will then be relieved from having
> >> to deal with KVM constraints.
> >>
> >> Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
> >> Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
> >> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
> >> Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
> >> Message-ID: <20230901194627.1214811-4-dbarboza@ventanamicro.com>
> >> Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
> >> ---
> >>   target/riscv/cpu.c | 65 ++++++++++++++++++++++++++++++----------------
> >>   1 file changed, 42 insertions(+), 23 deletions(-)
> >>
> >> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> >> index db640e7460..8e6d316500 100644
> >> --- a/target/riscv/cpu.c
> >> +++ b/target/riscv/cpu.c
> >> @@ -1943,6 +1943,46 @@ static void cpu_set_cfg_unavailable(Object *obj, 
> >> Visitor *v,
> >>   }
> >>   #endif
> >> +#ifndef CONFIG_USER_ONLY
> >
> > #ifdef CONFIG_KVM ?
>
> Yeah, CONFIG_KVM would be more fitting here. We're moving all this code to 
> kvm.c
> in "[PATCH v2 00/19] riscv: split TCG/KVM accelerators from cpu.c", and we 
> won't
> need neither in the end, so for now it's simpler to temporarily leave it like
> this.

There are CI failures, so I have converted this to #ifdef CONFIG_KVM
which should fix them.

Alistair

>
>
> Thanks,
>
> Daniel
>
> >
> >> +static void riscv_cpu_add_kvm_unavail_prop(Object *obj, const char 
> >> *prop_name)
> >> +{
> >> +    /* Check if KVM created the property already */
> >> +    if (object_property_find(obj, prop_name)) {
> >> +        return;
> >> +    }
> >> +
> >> +    /*
> >> +     * Set the default to disabled for every extension
> >> +     * unknown to KVM and error out if the user attempts
> >> +     * to enable any of them.
> >> +     */
> >> +    object_property_add(obj, prop_name, "bool",
> >> +                        NULL, cpu_set_cfg_unavailable,
> >> +                        NULL, (void *)prop_name);
> >> +}
> >> +
> >> +static void riscv_cpu_add_kvm_properties(Object *obj)
> >> +{
> >> +    Property *prop;
> >> +    DeviceState *dev = DEVICE(obj);
> >> +
> >> +    kvm_riscv_init_user_properties(obj);
> >> +    riscv_cpu_add_misa_properties(obj);
> >> +
> >> +    for (prop = riscv_cpu_extensions; prop && prop->name; prop++) {
> >> +        riscv_cpu_add_kvm_unavail_prop(obj, prop->name);
> >> +    }
> >> +
> >> +    for (int i = 0; i < ARRAY_SIZE(riscv_cpu_options); i++) {
> >> +        /* Check if KVM created the property already */
> >> +        if (object_property_find(obj, riscv_cpu_options[i].name)) {
> >> +            continue;
> >> +        }
> >> +        qdev_property_add_static(dev, &riscv_cpu_options[i]);
> >> +    }
> >> +}
> >> +#endif
> >> +
> >>   /*
> >>    * Add CPU properties with user-facing flags.
> >>    *
> >> @@ -1958,39 +1998,18 @@ static void riscv_cpu_add_user_properties(Object 
> >> *obj)
> >>       riscv_add_satp_mode_properties(obj);
> >>       if (kvm_enabled()) {
> >> -        kvm_riscv_init_user_properties(obj);
> >> +        riscv_cpu_add_kvm_properties(obj);
> >> +        return;
> >>       }
> >>   #endif
> >>       riscv_cpu_add_misa_properties(obj);
> >>       for (prop = riscv_cpu_extensions; prop && prop->name; prop++) {
> >> -#ifndef CONFIG_USER_ONLY
> >> -        if (kvm_enabled()) {
> >> -            /* Check if KVM created the property already */
> >> -            if (object_property_find(obj, prop->name)) {
> >> -                continue;
> >> -            }
> >> -
> >> -            /*
> >> -             * Set the default to disabled for every extension
> >> -             * unknown to KVM and error out if the user attempts
> >> -             * to enable any of them.
> >> -             */
> >> -            object_property_add(obj, prop->name, "bool",
> >> -                                NULL, cpu_set_cfg_unavailable,
> >> -                                NULL, (void *)prop->name);
> >> -            continue;
> >> -        }
> >> -#endif
> >>           qdev_property_add_static(dev, prop);
> >>       }
> >>       for (int i = 0; i < ARRAY_SIZE(riscv_cpu_options); i++) {
> >> -        /* Check if KVM created the property already */
> >> -        if (object_property_find(obj, riscv_cpu_options[i].name)) {
> >> -            continue;
> >> -        }
> >>           qdev_property_add_static(dev, &riscv_cpu_options[i]);
> >>       }
> >>   }
> >