[PATCH v4 13/22] perf jevents: Add context switch metrics for Intel

Ian Rogers posted 22 patches 2 months ago
[PATCH v4 13/22] perf jevents: Add context switch metrics for Intel
Posted by Ian Rogers 2 months ago
Metrics break down context switches for different kinds of
instruction.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/pmu-events/intel_metrics.py | 55 ++++++++++++++++++++++++++
 1 file changed, 55 insertions(+)

diff --git a/tools/perf/pmu-events/intel_metrics.py b/tools/perf/pmu-events/intel_metrics.py
index 1d886e416e7f..7cd933a28cfd 100755
--- a/tools/perf/pmu-events/intel_metrics.py
+++ b/tools/perf/pmu-events/intel_metrics.py
@@ -261,6 +261,60 @@ def IntelBr():
                      description="breakdown of retired branch instructions")
 
 
+def IntelCtxSw() -> MetricGroup:
+  cs = Event("context\-switches")
+  metrics = [
+      Metric("cs_rate", "Context switches per second", d_ratio(cs, interval_sec), "ctxsw/s")
+  ]
+
+  ev = Event("instructions")
+  metrics.append(Metric("cs_instr", "Instructions per context switch",
+                        d_ratio(ev, cs), "instr/cs"))
+
+  ev = Event("cycles")
+  metrics.append(Metric("cs_cycles", "Cycles per context switch",
+                        d_ratio(ev, cs), "cycles/cs"))
+
+  try:
+    ev = Event("MEM_INST_RETIRED.ALL_LOADS", "MEM_UOPS_RETIRED.ALL_LOADS")
+    metrics.append(Metric("cs_loads", "Loads per context switch",
+                          d_ratio(ev, cs), "loads/cs"))
+  except:
+    pass
+
+  try:
+    ev = Event("MEM_INST_RETIRED.ALL_STORES", "MEM_UOPS_RETIRED.ALL_STORES")
+    metrics.append(Metric("cs_stores", "Stores per context switch",
+                          d_ratio(ev, cs), "stores/cs"))
+  except:
+    pass
+
+  try:
+    ev = Event("BR_INST_RETIRED.NEAR_TAKEN", "BR_INST_RETIRED.TAKEN_JCC")
+    metrics.append(Metric("cs_br_taken", "Branches taken per context switch",
+                          d_ratio(ev, cs), "br_taken/cs"))
+  except:
+    pass
+
+  try:
+    l2_misses = (Event("L2_RQSTS.DEMAND_DATA_RD_MISS") +
+                 Event("L2_RQSTS.RFO_MISS") +
+                 Event("L2_RQSTS.CODE_RD_MISS"))
+    try:
+      l2_misses += Event("L2_RQSTS.HWPF_MISS", "L2_RQSTS.L2_PF_MISS", "L2_RQSTS.PF_MISS")
+    except:
+      pass
+
+    metrics.append(Metric("cs_l2_misses", "L2 misses per context switch",
+                          d_ratio(l2_misses, cs), "l2_misses/cs"))
+  except:
+    pass
+
+  return MetricGroup("cs", metrics,
+                     description = ("Number of context switches per second, instructions "
+                                    "retired & core cycles between context switches"))
+
+
 def IntelIlp() -> MetricGroup:
   tsc = Event("msr/tsc/")
   c0 = Event("msr/mperf/")
@@ -652,6 +706,7 @@ def main() -> None:
       Smi(),
       Tsx(),
       IntelBr(),
+      IntelCtxSw(),
       IntelIlp(),
       IntelL2(),
       IntelLdSt(),
-- 
2.46.1.824.gd892dcdcdd-goog