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

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Message-ID: <20170722161215.GA13329@nazgul.tnic>
Date:   Sat, 22 Jul 2017 18:12:15 +0200
From:   Borislav Petkov <bp@...e.de>
To:     Suravee Suthikulpanit <suravee.suthikulpanit@....com>
Cc:     linux-kernel@...r.kernel.org, x86@...nel.org, tglx@...utronix.de,
        mingo@...hat.com, hpa@...or.com, peterz@...radead.org,
        Yazen.Ghannam@....com
Subject: Re: [PATCH v2 1/2] x86/amd: Refactor topology extension related code

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@....com>
> ---
>  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!

Try again.

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
--