Re: [PATCH 14/32] x86/cpufeatures: Get max closid and max cbm len and clean feature comments and code

[Nilay Vaish]

On 12 July 2016 at 20:02, Fenghua Yu <fenghua.yu@xxxxxxxxx> wrote:
> From: Fenghua Yu <fenghua.yu@xxxxxxxxx>
>
> Define two new cpuid leaves for CAT and CDP. The leaves are used in
> x86_capability to avoid hard coded index.
>
> Clean comments for RDT, CAT_L3, and CDP_L3 cpufeatures.
>
> Signed-off-by: Fenghua Yu <fenghua.yu@xxxxxxxxx>
> Reviewed-by: Tony Luck <tony.luck@xxxxxxxxx>
> ---
>  arch/x86/include/asm/cpufeature.h  |  2 ++
>  arch/x86/include/asm/cpufeatures.h |  6 +++---
>  arch/x86/include/asm/processor.h   |  6 +++---
>  arch/x86/kernel/cpu/common.c       | 11 +++++++----
>  4 files changed, 15 insertions(+), 10 deletions(-)
>
> diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h
> index 483fb54..cd3b0bd 100644
> --- a/arch/x86/include/asm/cpufeature.h
> +++ b/arch/x86/include/asm/cpufeature.h
> @@ -28,6 +28,8 @@ enum cpuid_leafs
>         CPUID_8000_000A_EDX,
>         CPUID_7_ECX,
>         CPUID_8000_0007_EBX,
> +       CPUID_10_0_EBX,
> +       CPUID_10_1_ECX,
>  };
>
>  #ifdef CONFIG_X86_FEATURE_NAMES
> diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
> index 16489b3..588932a 100644
> --- a/arch/x86/include/asm/cpufeatures.h
> +++ b/arch/x86/include/asm/cpufeatures.h
> @@ -220,7 +220,7 @@
>  #define X86_FEATURE_RTM                ( 9*32+11) /* Restricted Transactional Memory */
>  #define X86_FEATURE_CQM                ( 9*32+12) /* Cache QoS Monitoring */
>  #define X86_FEATURE_MPX                ( 9*32+14) /* Memory Protection Extension */
> -#define X86_FEATURE_RDT                ( 9*32+15) /* Resource Allocation */
> +#define X86_FEATURE_RDT                ( 9*32+15) /* Resource Director Technology */
>  #define X86_FEATURE_AVX512F    ( 9*32+16) /* AVX-512 Foundation */
>  #define X86_FEATURE_AVX512DQ   ( 9*32+17) /* AVX-512 DQ (Double/Quad granular) Instructions */
>  #define X86_FEATURE_RDSEED     ( 9*32+18) /* The RDSEED instruction */
> @@ -289,10 +289,10 @@
>  #define X86_FEATURE_SMCA       (17*32+ 3) /* Scalable MCA */
>
>  /* Intel-defined CPU features, CPUID level 0x00000010:0 (ebx), word 18 */
> -#define X86_FEATURE_CAT_L3      (18*32+ 1) /* Cache Allocation L3 */
> +#define X86_FEATURE_CAT_L3     (18*32+ 1) /* Cache Allocation L3 */
>
>  /* Intel-defined CPU QoS Sub-leaf, CPUID level 0x00000010:1 (ecx), word 19 */
> -#define X86_FEATURE_CDP_L3     (19*32+ 2) /* Code data prioritization L3 */
> +#define X86_FEATURE_CDP_L3     (19*32+ 2) /* Code Data Prioritization L3 */
>
>  /*
>   * BUG word(s)
> diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
> index 598c9bc..308aa03 100644
> --- a/arch/x86/include/asm/processor.h
> +++ b/arch/x86/include/asm/processor.h
> @@ -119,9 +119,9 @@ struct cpuinfo_x86 {
>         int                     x86_cache_occ_scale;    /* scale to bytes */
>         int                     x86_power;
>         unsigned long           loops_per_jiffy;
> -       /* Cache Allocation values: */
> -       u16                     x86_cache_max_cbm_len;
> -       u16                     x86_cache_max_closid;
> +       /* Cache Allocation l3 values: */
> +       u16                     x86_l3_max_cbm_len;
> +       u16                     x86_l3_max_closid;
>         /* cpuid returned max cores value: */
>         u16                      x86_max_cores;
>         u16                     apicid;
> diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
> index a695e58..e945e70 100644
> --- a/arch/x86/kernel/cpu/common.c
> +++ b/arch/x86/kernel/cpu/common.c
> @@ -716,14 +716,17 @@ void get_cpu_cap(struct cpuinfo_x86 *c)
>                 u32 eax, ebx, ecx, edx;
>
>                 cpuid_count(0x00000010, 0, &eax, &ebx, &ecx, &edx);
> -               c->x86_capability[17] = ebx;
> +               c->x86_capability[CPUID_10_0_EBX] = ebx;
>
>                 if (cpu_has(c, X86_FEATURE_CAT_L3)) {
>
>                         cpuid_count(0x00000010, 1, &eax, &ebx, &ecx, &edx);
> -                       c->x86_cache_max_closid = edx + 1;
> -                       c->x86_cache_max_cbm_len = eax + 1;
> -                       c->x86_capability[18] = ecx;
> +                       c->x86_l3_max_closid = edx + 1;
> +                       c->x86_l3_max_cbm_len = eax + 1;
> +                       c->x86_capability[CPUID_10_1_ECX] = ecx;
> +               } else {
> +                       c->x86_l3_max_closid = -1;
> +                       c->x86_l3_max_cbm_len = -1;
>                 }
>         }
>

I think this patch should be earlier in this patch series where the
constants 17 and 18 were first used.  Similarly the renaming of
variables, I think, should be merged with the patch that originally
introduced them.

--
Nilay