[AArch64] Apply instruction counter computing overflow rules

cyring · May 12, 2024 · 1549ff7 · 1549ff7
1 parent a78e0ae
commit 1549ff7
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Showing 3 changed files with 28 additions and 7 deletions.
diff --git a/aarch64/corefreqk.c b/aarch64/corefreqk.c
@@ -2921,6 +2921,8 @@ static void Generic_Core_Counters_Clear(union SAVE_AREA_CORE *Save,
 			pmevcntr2_el0,	Core->Counter[T].C0.UCC,	\
 			pmccntr_el0,	Core->Counter[T].C0.URC,	\
 			pmevcntr3_el0,	Core->Counter[T].INST );	\
+									\
+	Core->Counter[T].INST &= INST_COUNTER_OVERFLOW;			\
 	/* Normalize frequency: */					\
 	Core->Counter[T].C1 = ( 					\
 		Core->Counter[T].TSC					\
@@ -3005,10 +3007,14 @@ static void Generic_Core_Counters_Clear(union SAVE_AREA_CORE *Save,
 
 #define Delta_INST(Core)						\
 ({	/* Delta of Retired Instructions */				\
-	Core->Delta.INST = (						\
-		Core->Counter[0].INST > Core->Counter[1].INST		\
-	)	? Core->Counter[0].INST - Core->Counter[1].INST 	\
-		: Core->Counter[1].INST - Core->Counter[0].INST;	\
+	if (Core->Counter[1].INST > Core->Counter[0].INST)		\
+		Core->Delta.INST  = Core->Counter[1].INST		\
+				  - Core->Counter[0].INST;		\
+	else {								\
+		Core->Delta.INST  = INST_COUNTER_OVERFLOW		\
+				  - Core->Counter[0].INST;		\
+		Core->Delta.INST += Core->Counter[1].INST;		\
+	}								\
 })
 
 #define PKG_Counters_Generic(Core, T)					\

diff --git a/aarch64/corefreqm.c b/aarch64/corefreqm.c
@@ -29,10 +29,17 @@
 ({									\
 	unsigned long long overhead = pSlice->Counter[1].INST		\
 				    - pSlice->Counter[0].INST;		\
-	pSlice->Delta.INST = pSlice->Counter[2].INST			\
-			   - pSlice->Counter[1].INST;			\
+	/*	Test and compute if counter has overflowed	*/	\
+	if (pSlice->Counter[2].INST > pSlice->Counter[1].INST)		\
+		pSlice->Delta.INST  = pSlice->Counter[2].INST		\
+				    - pSlice->Counter[1].INST;		\
+	else {								\
+		pSlice->Delta.INST  = INST_COUNTER_OVERFLOW		\
+				    - pSlice->Counter[1].INST;		\
+		pSlice->Delta.INST += pSlice->Counter[2].INST;		\
+	}								\
 	if (overhead <= pSlice->Delta.INST)				\
-		pSlice->Delta.INST -= overhead;				\
+		pSlice->Delta.INST -= overhead; 			\
 })
 
 void CallWith_RDTSC_RDPMC(	RO(SHM_STRUCT) *RO(Shm),
@@ -47,16 +54,22 @@ void CallWith_RDTSC_RDPMC(	RO(SHM_STRUCT) *RO(Shm),
 			pmevcntr3_el0,
 			pSlice->Counter[0].INST );
 
+	pSlice->Counter[0].INST &= INST_COUNTER_OVERFLOW;
+
 	RDTSC_PMCx1(	pSlice->Counter[1].TSC,
 			pmevcntr3_el0,
 			pSlice->Counter[1].INST );
 
+	pSlice->Counter[1].INST &= INST_COUNTER_OVERFLOW;
+
 	SliceFunc(RO(Shm), RW(Shm), cpu, arg);
 
 	RDTSC_PMCx1(	pSlice->Counter[2].TSC,
 			pmevcntr3_el0,
 			pSlice->Counter[2].INST );
 
+	pSlice->Counter[2].INST &= INST_COUNTER_OVERFLOW;
+
 	if (BITVAL(RW(Shm)->Proc.Sync, BURN)) {
 		DeltaTSC(pSlice);
 		DeltaINST(pSlice);

diff --git a/aarch64/coretypes.h b/aarch64/coretypes.h
@@ -253,6 +253,8 @@ enum CSTATES_ENCODING {
 
 #define CSTATES_ENCODING_COUNT	12
 
+#define	INST_COUNTER_OVERFLOW	0x7fffffff
+
 enum THM_POINTS {
 	THM_THRESHOLD_1,
 	THM_THRESHOLD_2,