[PATCH 03/12] perf/x86/intel: Fix DKT PEBS load/store direction for latency events
From: Dapeng Mi
Date: Wed Sep 16 2026 - 22:01:26 EST
Same issue exists on Darkmont, intel_dkt_pebs_event_constraints[]
applies LAT_CONSTRAINT constraints to
MEM_UOPS_RETIRED.{LOAD,STORE}_LATENCY, but does not set explicit
LOAD/STORE flags for those events.
The PEBS latency path (pebs_latency_data(), via cmt_latency_data) uses
the event flags to determine memory operation direction. Without an
explicit STORE flag, samples from MEM_UOPS_RETIRED.STORE_LATENCY can be
misclassified as LOADs.
Set explicit LOAD/STORE flags in intel_dkt_pebs_event_constraints[] for:
- MEM_UOPS_RETIRED.LOAD_LATENCY
- MEM_UOPS_RETIRED.STORE_LATENCY
This fixes incorrect STORE sample classification. Additionally remove
INTEL_HYBRID_LAT_CONSTRAINT() since no one uses it anymore.
Fixes: 65fd435095bb ("perf/x86/intel: Update event constraints for PTL")
Signed-off-by: Dapeng Mi <dapeng1.mi@xxxxxxxxxxxxxxx>
---
arch/x86/events/intel/ds.c | 4 ++--
arch/x86/events/perf_event.h | 4 ----
2 files changed, 2 insertions(+), 6 deletions(-)
diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c
index 434adf15d83c..95b3ed3097ab 100644
--- a/arch/x86/events/intel/ds.c
+++ b/arch/x86/events/intel/ds.c
@@ -1312,8 +1312,8 @@ struct event_constraint intel_cmt_pebs_event_constraints[] = {
struct event_constraint intel_dkt_pebs_event_constraints[] = {
/* Allow all events as PEBS with no flags */
- INTEL_HYBRID_LAT_CONSTRAINT(0x5d0, 0xff),
- INTEL_HYBRID_LAT_CONSTRAINT(0x6d0, 0xff),
+ INTEL_HYBRID_LDLAT_CONSTRAINT(0x5d0, 0xff),
+ INTEL_HYBRID_STLAT_CONSTRAINT(0x6d0, 0xff),
EVENT_CONSTRAINT_END
};
diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h
index c9c52f3ee4fc..5787053dd40a 100644
--- a/arch/x86/events/perf_event.h
+++ b/arch/x86/events/perf_event.h
@@ -710,10 +710,6 @@ struct cpu_hw_events {
__EVENT_CONSTRAINT(c, n, INTEL_ARCH_EVENT_MASK|X86_ALL_EVENT_FLAGS, \
HWEIGHT(n), 0, PERF_X86_EVENT_PEBS_ST)
-#define INTEL_HYBRID_LAT_CONSTRAINT(c, n) \
- __EVENT_CONSTRAINT(c, n, INTEL_ARCH_EVENT_MASK|X86_ALL_EVENT_FLAGS, \
- HWEIGHT(n), 0, PERF_X86_EVENT_PEBS_LAT_HYBRID)
-
#define INTEL_HYBRID_LDLAT_CONSTRAINT(c, n) \
__EVENT_CONSTRAINT(c, n, INTEL_ARCH_EVENT_MASK|X86_ALL_EVENT_FLAGS, \
HWEIGHT(n), 0, PERF_X86_EVENT_PEBS_LAT_HYBRID|PERF_X86_EVENT_PEBS_LD_HSW)
--
2.34.1