Re: [Qemu-devel] [PATCH] fixup! target-i386: x86_cpu_load_features() function

[Igor Mammedov <imammedo@redhat.com>]

On Mon, 10 Oct 2016 13:58:25 -0300
Eduardo Habkost <ehabkost@redhat.com> wrote:

> On Mon, Oct 10, 2016 at 02:25:32PM +0200, Igor Mammedov wrote:
> > On Fri,  7 Oct 2016 17:29:01 -0300
> > Eduardo Habkost <ehabkost@redhat.com> wrote:
> >   
> > > When probing for CPU model information, we need to reuse the code
> > > that initializes CPUID fields, but not the remaining side-effects
> > > of x86_cpu_realizefn(). Move that code to a separate function
> > > that can be reused later.
> > > 
> > > Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
> > > ---
> > > Changes v5 -> v6:
> > > * Move x86_cpu_filter_features() outside x86_cpu_load_features(),
> > >   as the CPU model querying API won't run
> > >   x86_cpu_filter_features() on most cases  
> >   
> > > 
> > > Changes v4 -> v5:
> > > * Fix typo on x86_cpu_load_features() comment
> > >   Reported-by: Paolo Bonzini <pbonzini@redhat.com>
> > > 
> > > Changes series v3 -> v4:
> > > * New patch added to series
> > > ---
> > >  target-i386/cpu.c | 67 +++++++++++++++++++++++++++++++++++--------------------
> > >  1 file changed, 43 insertions(+), 24 deletions(-)
> > > 
> > > diff --git a/target-i386/cpu.c b/target-i386/cpu.c
> > > index 1e8127b..23cc19b 100644
> > > --- a/target-i386/cpu.c
> > > +++ b/target-i386/cpu.c
> > > @@ -2993,34 +2993,13 @@ static void x86_cpu_enable_xsave_components(X86CPU *cpu)
> > >      env->features[FEAT_XSAVE_COMP_HI] = mask >> 32;
> > >  }
> > >  
> > > -#define IS_INTEL_CPU(env) ((env)->cpuid_vendor1 == CPUID_VENDOR_INTEL_1 && \
> > > -                           (env)->cpuid_vendor2 == CPUID_VENDOR_INTEL_2 && \
> > > -                           (env)->cpuid_vendor3 == CPUID_VENDOR_INTEL_3)
> > > -#define IS_AMD_CPU(env) ((env)->cpuid_vendor1 == CPUID_VENDOR_AMD_1 && \
> > > -                         (env)->cpuid_vendor2 == CPUID_VENDOR_AMD_2 && \
> > > -                         (env)->cpuid_vendor3 == CPUID_VENDOR_AMD_3)
> > > -static void x86_cpu_realizefn(DeviceState *dev, Error **errp)
> > > +/* Load CPUID data based on configured features */
> > > +static void x86_cpu_load_features(X86CPU *cpu, Error **errp)
> > >  {
> > > -    CPUState *cs = CPU(dev);
> > > -    X86CPU *cpu = X86_CPU(dev);
> > > -    X86CPUClass *xcc = X86_CPU_GET_CLASS(dev);
> > >      CPUX86State *env = &cpu->env;
> > > -    Error *local_err = NULL;
> > > -    static bool ht_warned;
> > >      FeatureWord w;
> > >      GList *l;
> > > -
> > > -    if (xcc->kvm_required && !kvm_enabled()) {
> > > -        char *name = x86_cpu_class_get_model_name(xcc);
> > > -        error_setg(&local_err, "CPU model '%s' requires KVM", name);
> > > -        g_free(name);
> > > -        goto out;
> > > -    }
> > > -
> > > -    if (cpu->apic_id == UNASSIGNED_APIC_ID) {
> > > -        error_setg(errp, "apic-id property was not initialized properly");
> > > -        return;
> > > -    }
> > > +    Error *local_err = NULL;
> > >  
> > >      /*TODO: cpu->host_features incorrectly overwrites features
> > >       * set using "feat=on|off". Once we fix this, we can convert
> > > @@ -3086,6 +3065,46 @@ static void x86_cpu_realizefn(DeviceState *dev, Error **errp)
> > >          env->cpuid_xlevel2 = env->cpuid_min_xlevel2;
> > >      }
> > >  
> > > +out:
> > > +    if (local_err != NULL) {
> > > +        error_propagate(errp, local_err);
> > > +    }
> > > +}
> > > +
> > > +#define IS_INTEL_CPU(env) ((env)->cpuid_vendor1 == CPUID_VENDOR_INTEL_1 && \
> > > +                           (env)->cpuid_vendor2 == CPUID_VENDOR_INTEL_2 && \
> > > +                           (env)->cpuid_vendor3 == CPUID_VENDOR_INTEL_3)
> > > +#define IS_AMD_CPU(env) ((env)->cpuid_vendor1 == CPUID_VENDOR_AMD_1 && \
> > > +                         (env)->cpuid_vendor2 == CPUID_VENDOR_AMD_2 && \
> > > +                         (env)->cpuid_vendor3 == CPUID_VENDOR_AMD_3)
> > > +static void x86_cpu_realizefn(DeviceState *dev, Error **errp)
> > > +{
> > > +    CPUState *cs = CPU(dev);
> > > +    X86CPU *cpu = X86_CPU(dev);
> > > +    X86CPUClass *xcc = X86_CPU_GET_CLASS(dev);
> > > +    CPUX86State *env = &cpu->env;
> > > +    Error *local_err = NULL;
> > > +    static bool ht_warned;
> > > +
> > > +    if (xcc->kvm_required && !kvm_enabled()) {
> > > +        char *name = x86_cpu_class_get_model_name(xcc);
> > > +        error_setg(&local_err, "CPU model '%s' requires KVM", name);
> > > +        g_free(name);
> > > +        goto out;
> > > +    }
> > > +
> > > +    if (cpu->apic_id == UNASSIGNED_APIC_ID) {
> > > +        error_setg(errp, "apic-id property was not initialized properly");
> > > +        return;
> > > +    }
> > > +
> > > +    x86_cpu_load_features(cpu, &local_err);
> > > +    if (local_err) {
> > > +        goto out;
> > > +    }
> > > +
> > > +    x86_cpu_filter_features(cpu);  
> > that makes 2 invocations of ^^ inside realize,
> > see followup line vvvv  
> 
> Oops, leftover from v5. Thanks for spotting that! Fixup below.
> 
> Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>

> ---
>  target-i386/cpu.c | 2 --
>  1 file changed, 2 deletions(-)
> 
> diff --git a/target-i386/cpu.c b/target-i386/cpu.c
> index 23cc19b..4294746 100644
> --- a/target-i386/cpu.c
> +++ b/target-i386/cpu.c
> @@ -3103,8 +3103,6 @@ static void x86_cpu_realizefn(DeviceState *dev, Error **errp)
>          goto out;
>      }
>  
> -    x86_cpu_filter_features(cpu);
> -
>      if (x86_cpu_filter_features(cpu) &&
>          (cpu->check_cpuid || cpu->enforce_cpuid)) {
>          x86_cpu_report_filtered_features(cpu);