[PATCH v5 03/15] perf jevents: Rewrite metrics in the same file with each other

From: Ian Rogers <irogers@google.com>
To: John Garry <john.g.garry@oracle.com>,
	Will Deacon <will@kernel.org>, James Clark <james.clark@arm.com>,
	Mike Leach <mike.leach@linaro.org>, Leo Yan <leo.yan@linaro.org>,
	Peter Zijlstra <peterz@infradead.org>,
	Ingo Molnar <mingo@redhat.com>,
	Arnaldo Carvalho de Melo <acme@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	Jiri Olsa <jolsa@kernel.org>, Namhyung Kim <namhyung@kernel.org>,
	Adrian Hunter <adrian.hunter@intel.com>,
	Kan Liang <kan.liang@linux.intel.com>,
	Kim Phillips <kim.phillips@amd.com>,
	Florian Fischer <florian.fischer@muhq.space>,
	Ravi Bangoria <ravi.bangoria@amd.com>,
	Xing Zhengjun <zhengjun.xing@linux.intel.com>,
	Rob Herring <robh@kernel.org>,
	Kang Minchul <tegongkang@gmail.com>,
	linux-arm-kernel@lists.infradead.org,
	linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org,
	Sandipan Das <sandipan.das@amd.com>,
	Jing Zhang <renyu.zj@linux.alibaba.com>,
	linuxppc-dev@lists.ozlabs.org, Kajol Jain <kjain@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>,
	Perry Taylor <perry.taylor@intel.com>,
	Caleb Biggers <caleb.biggers@intel.com>,
	Ian Rogers <irogers@google.com>
Subject: [PATCH v5 03/15] perf jevents: Rewrite metrics in the same file with each other
Date: Thu, 26 Jan 2023 15:36:33 -0800	[thread overview]
Message-ID: <20230126233645.200509-4-irogers@google.com> (raw)
In-Reply-To: <20230126233645.200509-1-irogers@google.com>

Rewrite metrics within the same file in terms of each other. For example, on Power8
other_stall_cpi is rewritten from:
"PM_CMPLU_STALL / PM_RUN_INST_CMPL - PM_CMPLU_STALL_BRU_CRU / PM_RUN_INST_CMPL - PM_CMPLU_STALL_FXU / PM_RUN_INST_CMPL - PM_CMPLU_STALL_VSU / PM_RUN_INST_CMPL - PM_CMPLU_STALL_LSU / PM_RUN_INST_CMPL - PM_CMPLU_STALL_NTCG_FLUSH / PM_RUN_INST_CMPL - PM_CMPLU_STALL_NO_NTF / PM_RUN_INST_CMPL"
to:
"stall_cpi - bru_cru_stall_cpi - fxu_stall_cpi - vsu_stall_cpi - lsu_stall_cpi - ntcg_flush_cpi - no_ntf_stall_cpi"
Which more closely matches the definition on Power9.

To avoid recomputation decorate the function with a cache.
---
 tools/perf/pmu-events/jevents.py | 21 ++++++++++++++++-----
 1 file changed, 16 insertions(+), 5 deletions(-)

diff --git a/tools/perf/pmu-events/jevents.py b/tools/perf/pmu-events/jevents.py
index 0416b7442171..15a1671740cc 100755
--- a/tools/perf/pmu-events/jevents.py
+++ b/tools/perf/pmu-events/jevents.py
@@ -3,6 +3,7 @@
 """Convert directories of JSON events to C code."""
 import argparse
 import csv
+from functools import lru_cache
 import json
 import metric
 import os
@@ -337,18 +338,28 @@ class JsonEvent:
     s = self.build_c_string()
     return f'{{ { _bcs.offsets[s] } }}, /* {s} */\n'
 
-
+@lru_cache(maxsize=None)
 def read_json_events(path: str, topic: str) -> Sequence[JsonEvent]:
   """Read json events from the specified file."""
-
   try:
-    result = json.load(open(path), object_hook=JsonEvent)
+    events = json.load(open(path), object_hook=JsonEvent)
   except BaseException as err:
     print(f"Exception processing {path}")
     raise
-  for event in result:
+  metrics: list[Tuple[str, metric.Expression]] = []
+  for event in events:
     event.topic = topic
-  return result
+    if event.metric_name and '-' not in event.metric_name:
+      metrics.append((event.metric_name, event.metric_expr))
+  updates = metric.RewriteMetricsInTermsOfOthers(metrics)
+  if updates:
+    for event in events:
+      if event.metric_name in updates:
+        # print(f'Updated {event.metric_name} from\n"{event.metric_expr}"\n'
+        #       f'to\n"{updates[event.metric_name]}"')
+        event.metric_expr = updates[event.metric_name]
+
+  return events
 
 def preprocess_arch_std_files(archpath: str) -> None:
   """Read in all architecture standard events."""
-- 
2.39.1.456.gfc5497dd1b-goog

