ftrace: Report unavailable events all at once

Emit one warning message or one exception referring to the whole list of
unavailable events, rather than spreading it through multiple calls. In strict
mode, this allows the user to fix the whole list of bogus events at once rather
than incrementally.

Signed-off-by: Douglas RAILLARD <douglas.raillard@arm.com>

devlib/trace/ftrace.py

@@ -125,21 +125,33 @@ class FtraceCollector(TraceCollector):
             self.target_binary = 'trace-cmd'
 
         # Validate required events to be traced
-        selected_events = []
+        def event_to_regex(event):
-        for event in self.events:
+            if not event.startswith('*'):
-            # Convert globs supported by FTrace into valid regexp globs
+                event = '*' + event
-            _event = event
+
-            if event[0] != '*':
+            return re.compile(event.replace('*', '.*'))
-                _event = '*' + event
+
-            event_re = re.compile(_event.replace('*', '.*'))
+        def event_is_in_list(event, events):
-            # Select events matching the required ones
+            return any(
-            if not list(filter(event_re.match, self.available_events)):
+                event_to_regex(event).match(_event)
-                message = 'Event [{}] not available for tracing'.format(event)
+                for _event in events
+            )
+
+        unavailable_events = [
+            event
+            for event in self.events
+            if not event_is_in_list(event, self.available_events)
+        ]
+        if unavailable_events:
+            message = 'Events not available for tracing: {}'.format(
+                ', '.join(unavailable_events)
+            )
             if strict:
                 raise TargetStableError(message)
-                self.target.logger.warning(message)
             else:
-                selected_events.append(event)
+                self.target.logger.warning(message)
+
+        selected_events = sorted(set(self.events) - set(unavailable_events))
 
         if self.tracer and self.tracer not in self.available_tracers:
             raise TargetStableError('Unsupported tracer "{}". Available tracers: {}'.format(