Re: [PATCH v7 03/16] i386/cpu: Consolidate the use of topo_info in cpu_x86_cpuid()

[Zhao Liu]

Hi Xiaoyao,

On Wed, Jan 10, 2024 at 07:52:38PM +0800, Xiaoyao Li wrote:
> Date: Wed, 10 Jan 2024 19:52:38 +0800
> From: Xiaoyao Li <xiaoyao.li@intel.com>
> Subject: Re: [PATCH v7 03/16] i386/cpu: Consolidate the use of topo_info in
>  cpu_x86_cpuid()
> 
> On 1/8/2024 4:27 PM, Zhao Liu wrote:
> > From: Zhao Liu <zhao1.liu@intel.com>
> > 
> > In cpu_x86_cpuid(), there are many variables in representing the cpu
> > topology, e.g., topo_info, cs->nr_cores/cs->nr_threads.
> 
> Please use comma instead of slash. cs->nr_cores/cs->nr_threads looks like
> one variable.

Okay.

> 
> > Since the names of cs->nr_cores/cs->nr_threads does not accurately
> > represent its meaning, the use of cs->nr_cores/cs->nr_threads is prone
> > to confusion and mistakes.
> > 
> > And the structure X86CPUTopoInfo names its members clearly, thus the
> > variable "topo_info" should be preferred.
> > 
> > In addition, in cpu_x86_cpuid(), to uniformly use the topology variable,
> > replace env->dies with topo_info.dies_per_pkg as well.
> > 
> > Suggested-by: Robert Hoo <robert.hu@linux.intel.com>
> > Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
> > Tested-by: Babu Moger <babu.moger@amd.com>
> > Tested-by: Yongwei Ma <yongwei.ma@intel.com>
> > Acked-by: Michael S. Tsirkin <mst@redhat.com>
> > ---
> > Changes since v3:
> >   * Fix typo. (Babu)
> > 
> > Changes since v1:
> >   * Extract cores_per_socket from the code block and use it as a local
> >     variable for cpu_x86_cpuid(). (Yanan)
> >   * Remove vcpus_per_socket variable and use cpus_per_pkg directly.
> >     (Yanan)
> >   * Replace env->dies with topo_info.dies_per_pkg in cpu_x86_cpuid().
> > ---
> >   target/i386/cpu.c | 31 ++++++++++++++++++-------------
> >   1 file changed, 18 insertions(+), 13 deletions(-)
> > 
> > diff --git a/target/i386/cpu.c b/target/i386/cpu.c
> > index c8d2a585723a..6f8fa772ecf8 100644
> > --- a/target/i386/cpu.c
> > +++ b/target/i386/cpu.c
> > @@ -6017,11 +6017,16 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t 
> > index, uint32_t count,
> >       uint32_t limit;
> >       uint32_t signature[3];
> >       X86CPUTopoInfo topo_info;
> > +    uint32_t cores_per_pkg;
> > +    uint32_t cpus_per_pkg;
> 
> I prefer to lps_per_pkg or threads_per_pkg.

Okay, lp is not common in QEMU code, so I would change this to
threads_per_pkg.

> 
> Other than it,
> 
> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>

Thanks!

-Zhao