Re: [PATCH v3] perf/x86: use hexidecimal value for cpuid

["Liang, Kan" <kan.liang@linux.intel.com>]

On 2023-03-22 1:37 a.m., Zhenyu Wang wrote:
> It's easier to use hexidecimal value instead of decimal for reading
> and following with SDM doc, also align with other cpuid calls. As new
> cpuid leaf would be added in future, this tries to convert current
> forms and would take it as convention for new leaf definition.
> 
> This changes name for both cpuid type and cpuid calls.

It seems the patch touches 3 CPUIDs, 0xa, 0x1c and 0x14, right?
The patch also crosses several different subsystems and drivers.
I think it may be better to divide the patch by CPUID. Each patch to
handle one CPUID. It's easier for review.

Also, can you please add a macro for the CPUID leaf number?
Please refer ARCH_PERFMON_EXT_LEAF (0x23).

Thanks,
Kan

> 
> Cc: Peter Zijlstra <peterz@infradead.org>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
> Cc: Mark Rutland <mark.rutland@arm.com>
> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
> Cc: Jiri Olsa <jolsa@kernel.org>
> Cc: Namhyung Kim <namhyung@kernel.org>
> Cc: Kan Liang <kan.liang@linux.intel.com>
> Cc: CodyYao-oc <CodyYao-oc@zhaoxin.com>
> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
> ---
> v3:
> - add more explanation in commit message for purpose of this
> - use lowercase number in call to align with current code
> 
> v2:
> - rename in cpuid data type as well
> 
>  arch/x86/events/intel/core.c      | 10 +++++-----
>  arch/x86/events/intel/lbr.c       |  8 ++++----
>  arch/x86/events/intel/pt.c        |  2 +-
>  arch/x86/events/zhaoxin/core.c    |  8 ++++----
>  arch/x86/include/asm/perf_event.h | 12 ++++++------
>  arch/x86/kvm/cpuid.c              |  4 ++--
>  arch/x86/kvm/vmx/pmu_intel.c      |  4 ++--
>  7 files changed, 24 insertions(+), 24 deletions(-)
> 
> diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
> index a3fb996a86a1..5487a39d4975 100644
> --- a/arch/x86/events/intel/core.c
> +++ b/arch/x86/events/intel/core.c
> @@ -5170,7 +5170,7 @@ static __init void intel_arch_events_quirk(void)
>  
>  static __init void intel_nehalem_quirk(void)
>  {
> -	union cpuid10_ebx ebx;
> +	union cpuid_0xa_ebx ebx;
>  
>  	ebx.full = x86_pmu.events_maskl;
>  	if (ebx.split.no_branch_misses_retired) {
> @@ -5878,9 +5878,9 @@ __init int intel_pmu_init(void)
>  	struct attribute **td_attr    = &empty_attrs;
>  	struct attribute **mem_attr   = &empty_attrs;
>  	struct attribute **tsx_attr   = &empty_attrs;
> -	union cpuid10_edx edx;
> -	union cpuid10_eax eax;
> -	union cpuid10_ebx ebx;
> +	union cpuid_0xa_edx edx;
> +	union cpuid_0xa_eax eax;
> +	union cpuid_0xa_ebx ebx;
>  	unsigned int fixed_mask;
>  	bool pmem = false;
>  	int version, i;
> @@ -5903,7 +5903,7 @@ __init int intel_pmu_init(void)
>  	 * Check whether the Architectural PerfMon supports
>  	 * Branch Misses Retired hw_event or not.
>  	 */
> -	cpuid(10, &eax.full, &ebx.full, &fixed_mask, &edx.full);
> +	cpuid(0xa, &eax.full, &ebx.full, &fixed_mask, &edx.full);
>  	if (eax.split.mask_length < ARCH_PERFMON_EVENTS_COUNT)
>  		return -ENODEV;
>  
> diff --git a/arch/x86/events/intel/lbr.c b/arch/x86/events/intel/lbr.c
> index c3b0d15a9841..616a6904af03 100644
> --- a/arch/x86/events/intel/lbr.c
> +++ b/arch/x86/events/intel/lbr.c
> @@ -1497,16 +1497,16 @@ static bool is_arch_lbr_xsave_available(void)
>  void __init intel_pmu_arch_lbr_init(void)
>  {
>  	struct pmu *pmu = x86_get_pmu(smp_processor_id());
> -	union cpuid28_eax eax;
> -	union cpuid28_ebx ebx;
> -	union cpuid28_ecx ecx;
> +	union cpuid_0x1c_eax eax;
> +	union cpuid_0x1c_ebx ebx;
> +	union cpuid_0x1c_ecx ecx;
>  	unsigned int unused_edx;
>  	bool arch_lbr_xsave;
>  	size_t size;
>  	u64 lbr_nr;
>  
>  	/* Arch LBR Capabilities */
> -	cpuid(28, &eax.full, &ebx.full, &ecx.full, &unused_edx);
> +	cpuid(0x1c, &eax.full, &ebx.full, &ecx.full, &unused_edx);
>  
>  	lbr_nr = fls(eax.split.lbr_depth_mask) * 8;
>  	if (!lbr_nr)
> diff --git a/arch/x86/events/intel/pt.c b/arch/x86/events/intel/pt.c
> index 42a55794004a..da3c5d748365 100644
> --- a/arch/x86/events/intel/pt.c
> +++ b/arch/x86/events/intel/pt.c
> @@ -235,7 +235,7 @@ static int __init pt_pmu_hw_init(void)
>  	}
>  
>  	for (i = 0; i < PT_CPUID_LEAVES; i++) {
> -		cpuid_count(20, i,
> +		cpuid_count(0x14, i,
>  			    &pt_pmu.caps[CPUID_EAX + i*PT_CPUID_REGS_NUM],
>  			    &pt_pmu.caps[CPUID_EBX + i*PT_CPUID_REGS_NUM],
>  			    &pt_pmu.caps[CPUID_ECX + i*PT_CPUID_REGS_NUM],
> diff --git a/arch/x86/events/zhaoxin/core.c b/arch/x86/events/zhaoxin/core.c
> index 3e9acdaeed1e..1d071974f4db 100644
> --- a/arch/x86/events/zhaoxin/core.c
> +++ b/arch/x86/events/zhaoxin/core.c
> @@ -504,9 +504,9 @@ static __init void zhaoxin_arch_events_quirk(void)
>  
>  __init int zhaoxin_pmu_init(void)
>  {
> -	union cpuid10_edx edx;
> -	union cpuid10_eax eax;
> -	union cpuid10_ebx ebx;
> +	union cpuid_0xa_edx edx;
> +	union cpuid_0xa_eax eax;
> +	union cpuid_0xa_ebx ebx;
>  	struct event_constraint *c;
>  	unsigned int unused;
>  	int version;
> @@ -517,7 +517,7 @@ __init int zhaoxin_pmu_init(void)
>  	 * Check whether the Architectural PerfMon supports
>  	 * hw_event or not.
>  	 */
> -	cpuid(10, &eax.full, &ebx.full, &unused, &edx.full);
> +	cpuid(0xa, &eax.full, &ebx.full, &unused, &edx.full);
>  
>  	if (eax.split.mask_length < ARCH_PERFMON_EVENTS_COUNT - 1)
>  		return -ENODEV;
> diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h
> index 8fc15ed5e60b..0d2d735c8167 100644
> --- a/arch/x86/include/asm/perf_event.h
> +++ b/arch/x86/include/asm/perf_event.h
> @@ -125,7 +125,7 @@
>   * Intel "Architectural Performance Monitoring" CPUID
>   * detection/enumeration details:
>   */
> -union cpuid10_eax {
> +union cpuid_0xa_eax {
>  	struct {
>  		unsigned int version_id:8;
>  		unsigned int num_counters:8;
> @@ -135,7 +135,7 @@ union cpuid10_eax {
>  	unsigned int full;
>  };
>  
> -union cpuid10_ebx {
> +union cpuid_0xa_ebx {
>  	struct {
>  		unsigned int no_unhalted_core_cycles:1;
>  		unsigned int no_instructions_retired:1;
> @@ -148,7 +148,7 @@ union cpuid10_ebx {
>  	unsigned int full;
>  };
>  
> -union cpuid10_edx {
> +union cpuid_0xa_edx {
>  	struct {
>  		unsigned int num_counters_fixed:5;
>  		unsigned int bit_width_fixed:8;
> @@ -170,7 +170,7 @@ union cpuid10_edx {
>  /*
>   * Intel Architectural LBR CPUID detection/enumeration details:
>   */
> -union cpuid28_eax {
> +union cpuid_0x1c_eax {
>  	struct {
>  		/* Supported LBR depth values */
>  		unsigned int	lbr_depth_mask:8;
> @@ -183,7 +183,7 @@ union cpuid28_eax {
>  	unsigned int		full;
>  };
>  
> -union cpuid28_ebx {
> +union cpuid_0x1c_ebx {
>  	struct {
>  		/* CPL Filtering Supported */
>  		unsigned int    lbr_cpl:1;
> @@ -195,7 +195,7 @@ union cpuid28_ebx {
>  	unsigned int            full;
>  };
>  
> -union cpuid28_ecx {
> +union cpuid_0x1c_ecx {
>  	struct {
>  		/* Mispredict Bit Supported */
>  		unsigned int    lbr_mispred:1;
> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
> index 599aebec2d52..57f43dc87538 100644
> --- a/arch/x86/kvm/cpuid.c
> +++ b/arch/x86/kvm/cpuid.c
> @@ -967,8 +967,8 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)
>  		}
>  		break;
>  	case 0xa: { /* Architectural Performance Monitoring */
> -		union cpuid10_eax eax;
> -		union cpuid10_edx edx;
> +		union cpuid_0xa_eax eax;
> +		union cpuid_0xa_edx edx;
>  
>  		if (!static_cpu_has(X86_FEATURE_ARCH_PERFMON)) {
>  			entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
> diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
> index e8a3be0b9df9..f4b165667ca9 100644
> --- a/arch/x86/kvm/vmx/pmu_intel.c
> +++ b/arch/x86/kvm/vmx/pmu_intel.c
> @@ -512,8 +512,8 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
>  	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
>  	struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
>  	struct kvm_cpuid_entry2 *entry;
> -	union cpuid10_eax eax;
> -	union cpuid10_edx edx;
> +	union cpuid_0xa_eax eax;
> +	union cpuid_0xa_edx edx;
>  	u64 perf_capabilities;
>  	u64 counter_mask;
>  	int i;