[PATCH v4 07/17] perf jevents: Sort json files entries

[Ian Rogers <irogers@google.com>]

Sort the json files entries on conversion to C. The sort order tries to
replicated cmp_sevent from pmu.c so that the input there is already
sorted except for sysfs events.

Add the topic to JsonEvent on reading to simplify. Remove an unnecessary
lambda in the json reading.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/pmu-events/jevents.py | 48 +++++++++++++++++++++++---------
 1 file changed, 35 insertions(+), 13 deletions(-)

diff --git a/tools/perf/pmu-events/jevents.py b/tools/perf/pmu-events/jevents.py
index 12d2daf3570c..30e0e792221a 100755
--- a/tools/perf/pmu-events/jevents.py
+++ b/tools/perf/pmu-events/jevents.py
@@ -18,6 +18,8 @@ _sys_event_tables = []
 _arch_std_events = {}
 # Track whether an events table is currently being defined and needs closing.
 _close_table = False
+# Events to write out when the table is closed
+_pending_events = []
 
 
 def removesuffix(s: str, suffix: str) -> str:
@@ -127,6 +129,7 @@ class JsonEvent:
       eventcode |= int(jd['ExtSel']) << 8
     configcode = int(jd['ConfigCode'], 0) if 'ConfigCode' in jd else None
     self.name = jd['EventName'].lower() if 'EventName' in jd else None
+    self.topic = ''
     self.compat = jd.get('Compat')
     self.desc = fixdesc(jd.get('BriefDescription'))
     self.long_desc = fixdesc(jd.get('PublicDescription'))
@@ -199,7 +202,7 @@ class JsonEvent:
         s += f'\t{attr} = {value},\n'
     return s + '}'
 
-  def to_c_string(self, topic_local: str) -> str:
+  def to_c_string(self) -> str:
     """Representation of the event as a C struct initializer."""
 
     def attr_string(attr: str, value: str) -> str:
@@ -211,25 +214,27 @@ class JsonEvent:
       return attr_string(attr, getattr(self, attr))
 
     s = '{\n'
-    s += f'\t.topic = "{topic_local}",\n'
     for attr in [
         'aggr_mode', 'compat', 'deprecated', 'desc', 'event', 'long_desc',
         'metric_constraint', 'metric_expr', 'metric_group', 'metric_name',
-        'name', 'perpkg', 'pmu', 'unit'
+        'name', 'perpkg', 'pmu', 'topic', 'unit'
     ]:
       s += str_if_present(self, attr)
     s += '},\n'
     return s
 
 
-def read_json_events(path: str) -> Sequence[JsonEvent]:
+def read_json_events(path: str, topic: str) -> Sequence[JsonEvent]:
   """Read json events from the specified file."""
 
   try:
-    return json.load(open(path), object_hook=lambda d: JsonEvent(d))
+    result = json.load(open(path), object_hook=JsonEvent)
   except BaseException as err:
     print(f"Exception processing {path}")
     raise
+  for event in result:
+    event.topic = topic
+  return result
 
 
 def preprocess_arch_std_files(archpath: str) -> None:
@@ -237,7 +242,7 @@ def preprocess_arch_std_files(archpath: str) -> None:
   global _arch_std_events
   for item in os.scandir(archpath):
     if item.is_file() and item.name.endswith('.json'):
-      for event in read_json_events(item.path):
+      for event in read_json_events(item.path, topic=''):
         if event.name:
           _arch_std_events[event.name.lower()] = event
 
@@ -251,19 +256,36 @@ def print_events_table_prefix(tblname: str) -> None:
   _close_table = True
 
 
-def print_events_table_entries(item: os.DirEntry, topic: str) -> None:
-  """Create contents of an events table."""
+def add_events_table_entries(item: os.DirEntry, topic: str) -> None:
+  """Add contents of file to _pending_events table."""
   if not _close_table:
     raise IOError('Table entries missing prefix')
-  for event in read_json_events(item.path):
-    _args.output_file.write(event.to_c_string(topic))
+  for e in read_json_events(item.path, topic):
+    _pending_events.append(e)
 
 
 def print_events_table_suffix() -> None:
   """Optionally close events table."""
+
+  def event_cmp_key(j: JsonEvent):
+    def fix_none(s: str):
+      if s is None:
+        return ''
+      return s
+
+    return (not j.desc is None, fix_none(j.topic), fix_none(j.name), fix_none(j.pmu),
+            fix_none(j.metric_name))
+
   global _close_table
-  if _close_table:
-    _args.output_file.write("""{
+  if not _close_table:
+    return
+
+  global _pending_events
+  for event in sorted(_pending_events, key=event_cmp_key):
+    _args.output_file.write(event.to_c_string())
+    _pending_events = []
+
+  _args.output_file.write("""{
 \t.name = 0,
 \t.event = 0,
 \t.desc = 0,
@@ -306,7 +328,7 @@ def process_one_file(parents: Sequence[str], item: os.DirEntry) -> None:
   if not item.is_file() or not item.name.endswith('.json'):
     return
 
-  print_events_table_entries(item, get_topic(item.name))
+  add_events_table_entries(item, get_topic(item.name))
 
 
 def print_mapping_table(archs: Sequence[str]) -> None:
-- 
2.37.1.559.g78731f0fdb-goog