Re: [RESEND Patch 1/2] perf/x86/intel: Only check GP counters for PEBS constraints validation
From: Chen, Zide
Date: Fri Mar 06 2026 - 20:27:58 EST
On 2/27/2026 9:33 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@xxxxxxxxxxxxxxx>
> ---
LGTM.
Reviewed-by: Zide Chen <zide.chen@xxxxxxxxx>
> 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