[PATCH V2 2/7] powerpc/perf: Update the PMU group constraints for l2l3 events in power10

Athira Rajeev atrajeev at linux.vnet.ibm.com
Fri Nov 27 03:54:39 AEDT 2020


In Power9, L2/L3 bus events are always available as a
"bank" of 4 events. To obtain the counts for any of the
l2/l3 bus events in a given bank, the user will have to
program PMC4 with corresponding l2/l3 bus event for that
bank.

Commit 59029136d750 ("powerpc/perf: Add constraints for power9 l2/l3 bus events")
enforced this rule in Power9. But this is not valid for
Power10, since in Power10 Monitor Mode Control Register2
(MMCR2) has bits to configure l2/l3 event bits. Hence remove
this PMC4 constraint check from power10.

Since the l2/l3 bits in MMCR2 are not per-pmc, patch handles
group constrints checks for l2/l3 bits in MMCR2.

Fixes: a64e697cef23 ("powerpc/perf: power10 Performance Monitoring support")
Signed-off-by: Athira Rajeev <atrajeev at linux.vnet.ibm.com>
---
 arch/powerpc/perf/isa207-common.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/perf/isa207-common.c b/arch/powerpc/perf/isa207-common.c
index f57f54f..38ed450c 100644
--- a/arch/powerpc/perf/isa207-common.c
+++ b/arch/powerpc/perf/isa207-common.c
@@ -311,9 +311,11 @@ int isa207_get_constraint(u64 event, unsigned long *maskp, unsigned long *valp)
 	}
 
 	if (unit >= 6 && unit <= 9) {
-		if (cpu_has_feature(CPU_FTR_ARCH_31) && (unit == 6)) {
-			mask |= CNST_L2L3_GROUP_MASK;
-			value |= CNST_L2L3_GROUP_VAL(event >> p10_L2L3_EVENT_SHIFT);
+		if (cpu_has_feature(CPU_FTR_ARCH_31)) {
+			if (unit == 6) {
+				mask |= CNST_L2L3_GROUP_MASK;
+				value |= CNST_L2L3_GROUP_VAL(event >> p10_L2L3_EVENT_SHIFT);
+			}
 		} else if (cpu_has_feature(CPU_FTR_ARCH_300)) {
 			mask  |= CNST_CACHE_GROUP_MASK;
 			value |= CNST_CACHE_GROUP_VAL(event & 0xff);
-- 
1.8.3.1



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