Re: [PATCH v2 1/2] x86/amd: Refactor topology extension related code

[Suravee Suthikulpanit]

Boris,

On 7/22/17 23:12, Borislav Petkov wrote:
> On Fri, Jul 21, 2017 at 09:00:38PM -0500, Suravee Suthikulpanit wrote:
> > Refactoring in preparation for subsequent changes.
> > There is no functional change.
> >
> > Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
> > ---
> >  arch/x86/kernel/cpu/amd.c | 79 ++++++++++++++++++++++++++---------------------
> >  1 file changed, 44 insertions(+), 35 deletions(-)
> >
> > diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
> > index bb5abe8..74d8d7c 100644
> > --- a/arch/x86/kernel/cpu/amd.c
> > +++ b/arch/x86/kernel/cpu/amd.c
> > @@ -297,54 +297,63 @@ static int nearby_node(int apicid)
> >  #endif
> >
> >  /*
> > - * Fixup core topology information for
> > - * (1) AMD multi-node processors
> > - *     Assumption: Number of cores in each internal node is the same.
> > - * (2) AMD processors supporting compute units
> > + * Get topology information via X86_FEATURE_TOPOEXT
> >   */
> > -#ifdef CONFIG_SMP
> > -static void amd_get_topology(struct cpuinfo_x86 *c)
> > +static void __get_topoext(struct cpuinfo_x86 *c)
> >  {
> > -	u8 node_id;
> > +	u32 eax, ebx, ecx, edx;
> >  	int cpu = smp_processor_id();
> >
> > -	/* get information required for multi-node processors */
> > -	if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
> > -		u32 eax, ebx, ecx, edx;
> > +	cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
> >
> > -		cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
> > +	smp_num_siblings = ((ebx >> 8) & 0xff) + 1;
> >
> > -		node_id  = ecx & 0xff;
>
> When reviewers ask you about a preparatory cleanup patch, you don't
> sneak in changes in it - you *only* *move* the code so that the change
> is *absolutely* comprehensible. Ontop you do changes. Don't tell me you
> didn't know that!

I know that we should not sneak in change. I might have missed something here.

Are you referring to the part that I moved the "node_id = ecx & 0xff" from the 
top level of the function to inside the "if/else" logic where it is the only 
place that used within this new refactored __get_topoext() and there is nothing 
changed functionally? If that's really the case, I'll fix it.

Thanks,
Suravee