Re: [RESEND Patch 1/2] perf/x86/intel: Only check GP counters for PEBS constraints validation

["Mi, Dapeng" <dapeng1.mi@linux.intel.com>]

Hi Peter,

Could you please review and merge this change? This change suppose to be
low risky. Without this change, the dynamic constraints check would trigger
false positive on DMR/NVL. Thanks.


On 2/28/2026 1:33 PM, Dapeng Mi wrote:
> It's good enough to only check GP counters for PEBS constraints
> validation since constraints overlap can only happen on GP counters.
>
> Besides opportunistically refine the code style and use pr_warn() to
> replace pr_info() as the message itself is a warning message.
>
> Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
> ---
>  arch/x86/events/intel/core.c | 22 ++++++++++++++--------
>  1 file changed, 14 insertions(+), 8 deletions(-)
>
> diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
> index cf3a4fe06ff2..4768236c054b 100644
> --- a/arch/x86/events/intel/core.c
> +++ b/arch/x86/events/intel/core.c
> @@ -5770,7 +5770,7 @@ static void __intel_pmu_check_dyn_constr(struct event_constraint *constr,
>  			}
>  
>  			if (check_fail) {
> -				pr_info("The two events 0x%llx and 0x%llx may not be "
> +				pr_warn("The two events 0x%llx and 0x%llx may not be "
>  					"fully scheduled under some circumstances as "
>  					"%s.\n",
>  					c1->code, c2->code, dyn_constr_type_name[type]);
> @@ -5783,6 +5783,7 @@ static void intel_pmu_check_dyn_constr(struct pmu *pmu,
>  				       struct event_constraint *constr,
>  				       u64 cntr_mask)
>  {
> +	u64 gp_mask = GENMASK_ULL(INTEL_PMC_MAX_GENERIC - 1, 0);
>  	enum dyn_constr_type i;
>  	u64 mask;
>  
> @@ -5797,20 +5798,25 @@ static void intel_pmu_check_dyn_constr(struct pmu *pmu,
>  				mask = x86_pmu.lbr_counters;
>  			break;
>  		case DYN_CONSTR_ACR_CNTR:
> -			mask = hybrid(pmu, acr_cntr_mask64) & GENMASK_ULL(INTEL_PMC_MAX_GENERIC - 1, 0);
> +			mask = hybrid(pmu, acr_cntr_mask64) & gp_mask;
>  			break;
>  		case DYN_CONSTR_ACR_CAUSE:
> -			if (hybrid(pmu, acr_cntr_mask64) == hybrid(pmu, acr_cause_mask64))
> +			if (hybrid(pmu, acr_cntr_mask64) ==
> +					hybrid(pmu, acr_cause_mask64))
>  				continue;
> -			mask = hybrid(pmu, acr_cause_mask64) & GENMASK_ULL(INTEL_PMC_MAX_GENERIC - 1, 0);
> +			mask = hybrid(pmu, acr_cause_mask64) & gp_mask;
>  			break;
>  		case DYN_CONSTR_PEBS:
> -			if (x86_pmu.arch_pebs)
> -				mask = hybrid(pmu, arch_pebs_cap).counters;
> +			if (x86_pmu.arch_pebs) {
> +				mask = hybrid(pmu, arch_pebs_cap).counters &
> +				       gp_mask;
> +			}
>  			break;
>  		case DYN_CONSTR_PDIST:
> -			if (x86_pmu.arch_pebs)
> -				mask = hybrid(pmu, arch_pebs_cap).pdists;
> +			if (x86_pmu.arch_pebs) {
> +				mask = hybrid(pmu, arch_pebs_cap).pdists &
> +				       gp_mask;
> +			}
>  			break;
>  		default:
>  			pr_warn("Unsupported dynamic constraint type %d\n", i);
>
> base-commit: 6de23f81a5e08be8fbf5e8d7e9febc72a5b5f27f