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Subject[PATCH v6 5/6] perf vendor events arm64: Update stall_slot workaround for N2 r0p3
Date
N2 r0p3 doesn't require the workaround [1], so gating on (#slots - 5) no
longer works because all N2s have 5 slots. Use the new expression
builtin that allows calling strcmp_cpuid_str() and comparing CPUIDs in
metric formulas.

In this case, the commented formula looks like this:

strcmp_cpuid_str(0x410fd493) # greater than or equal to N2 r0p3
| strcmp_cpuid_str(0x410fd490) ^ 1 # OR NOT any version of N2

[1]: https://gitlab.arm.com/telemetry-solution/telemetry-solution/-/blob/main/data/pmu/cpu/neoverse/neoverse-n2-r0p3.json
Signed-off-by: James Clark <james.clark@arm.com>
---
.../pmu-events/arch/arm64/arm/neoverse-n2-v2/metrics.json | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/tools/perf/pmu-events/arch/arm64/arm/neoverse-n2-v2/metrics.json b/tools/perf/pmu-events/arch/arm64/arm/neoverse-n2-v2/metrics.json
index 8ad15b726dca..9757cc178bdf 100644
--- a/tools/perf/pmu-events/arch/arm64/arm/neoverse-n2-v2/metrics.json
+++ b/tools/perf/pmu-events/arch/arm64/arm/neoverse-n2-v2/metrics.json
@@ -1,15 +1,15 @@
[
{
"ArchStdEvent": "FRONTEND_BOUND",
- "MetricExpr": "((stall_slot_frontend) if (#slots - 5) else (stall_slot_frontend - cpu_cycles)) / (#slots * cpu_cycles)"
+ "MetricExpr": "((stall_slot_frontend) if (strcmp_cpuid_str(0x410fd493) | strcmp_cpuid_str(0x410fd490) ^ 1) else (stall_slot_frontend - cpu_cycles)) / (#slots * cpu_cycles)"
},
{
"ArchStdEvent": "BAD_SPECULATION",
- "MetricExpr": "(1 - op_retired / op_spec) * (1 - (stall_slot if (#slots - 5) else (stall_slot - cpu_cycles)) / (#slots * cpu_cycles))"
+ "MetricExpr": "(1 - op_retired / op_spec) * (1 - (stall_slot if (strcmp_cpuid_str(0x410fd493) | strcmp_cpuid_str(0x410fd490) ^ 1) else (stall_slot - cpu_cycles)) / (#slots * cpu_cycles))"
},
{
"ArchStdEvent": "RETIRING",
- "MetricExpr": "(op_retired / op_spec) * (1 - (stall_slot if (#slots - 5) else (stall_slot - cpu_cycles)) / (#slots * cpu_cycles))"
+ "MetricExpr": "(op_retired / op_spec) * (1 - (stall_slot if (strcmp_cpuid_str(0x410fd493) | strcmp_cpuid_str(0x410fd490) ^ 1) else (stall_slot - cpu_cycles)) / (#slots * cpu_cycles))"
},
{
"ArchStdEvent": "BACKEND_BOUND"
@@ -201,7 +201,7 @@
"ScaleUnit": "100%"
},
{
- "MetricExpr": "OP_RETIRED / OP_SPEC * (1 - (STALL_SLOT if (#slots - 5) else (STALL_SLOT - CPU_CYCLES)) / (#slots * CPU_CYCLES))",
+ "MetricExpr": "OP_RETIRED / OP_SPEC * (1 - (STALL_SLOT if (strcmp_cpuid_str(0x410fd493) | strcmp_cpuid_str(0x410fd490) ^ 1) else (STALL_SLOT - CPU_CYCLES)) / (#slots * CPU_CYCLES))",
"BriefDescription": "The truly effective ratio of micro-operations executed by the CPU, which means that misprediction and stall are not included",
"MetricGroup": "PEutilization",
"MetricName": "cpu_utilization",
--
2.34.1
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