Support instrumentation for linking a timer to a node

Signed-off-by: Christophe Bedard <bedard.christophe@gmail.com>

tracetools_analysis/tracetools_analysis/data_model/ros2.py

@@ -78,6 +78,10 @@ class Ros2DataModel(DataModel):
                                             'period',
                                             'tid'])
         self.timers.set_index(['timer_handle'], inplace=True, drop=True)
+        self.timer_node_links = pd.DataFrame(columns=['timer_handle',
+                                                      'timestamp',
+                                                      'node_handle'])
+        self.timer_node_links.set_index(['timer_handle'], inplace=True, drop=True)
 
         self.callback_objects = pd.DataFrame(columns=['reference',
                                                       'timestamp',
@@ -142,6 +146,11 @@ class Ros2DataModel(DataModel):
     ) -> None:
         self.timers.loc[handle] = [timestamp, period, tid]
 
+    def add_timer_node_link(
+        self, handle, timestamp, node_handle
+    ) -> None:
+        self.timer_node_links.loc[handle] = [timestamp, node_handle]
+
     def add_callback_object(
         self, reference, timestamp, callback_object
     ) -> None:
@@ -205,6 +214,9 @@ class Ros2DataModel(DataModel):
         print('Timers:')
         print(self.timers.to_string())
         print()
+        print('Timer-node links:')
+        print(self.timer_node_links.to_string())
+        print()
         print('Callback objects:')
         print(self.callback_objects.to_string())
         print()
@@ -215,7 +227,6 @@ class Ros2DataModel(DataModel):
         print(self.callback_instances.to_string())
         print()
         print('Lifecycle state machines:')
-        print()
         print(self.lifecycle_state_machines.to_string())
         print()
         print('Lifecycle transitions:')

tracetools_analysis/tracetools_analysis/processor/ros2.py

@@ -63,6 +63,8 @@ class Ros2Handler(EventHandler):
                 self._handle_rcl_timer_init,
             'ros2:rclcpp_timer_callback_added':
                 self._handle_rclcpp_timer_callback_added,
+            'ros2:rclcpp_timer_link_node':
+                self._handle_rclcpp_timer_link_node,
             'ros2:rclcpp_callback_register':
                 self._handle_rclcpp_callback_register,
             'ros2:callback_start':
@@ -198,6 +200,14 @@ class Ros2Handler(EventHandler):
         callback_object = get_field(event, 'callback')
         self.data.add_callback_object(handle, timestamp, callback_object)
 
+    def _handle_rclcpp_timer_link_node(
+        self, event: Dict, metadata: EventMetadata,
+    ) -> None:
+        handle = get_field(event, 'timer_handle')
+        timestamp = metadata.timestamp
+        node_handle = get_field(event, 'node_handle')
+        self.data.add_timer_node_link(handle, timestamp, node_handle)
+
     def _handle_rclcpp_callback_register(
         self, event: Dict, metadata: EventMetadata,
     ) -> None:

tracetools_analysis/tracetools_analysis/utils/ros2.py

@@ -228,14 +228,18 @@ class Ros2DataModelUtil(DataModelUtil):
         :param timer_handle: the timer handle value
         :return: a dictionary with name:value info, or `None` if it fails
         """
-        # TODO find a way to link a timer to a specific node
         if timer_handle not in self.data.timers.index:
             return None
 
+        node_handle = self.data.timer_node_links.loc[timer_handle, 'node_handle']
+        node_handle_info = self.get_node_handle_info(node_handle)
+        if node_handle_info is None:
+            return None
+
         tid = self.data.timers.loc[timer_handle, 'tid']
         period_ns = self.data.timers.loc[timer_handle, 'period']
         period_ms = period_ns / 1000000.0
-        return {'tid': tid, 'period': f'{period_ms:.0f} ms'}
+        return {**node_handle_info, 'tid': tid, 'period': f'{period_ms:.0f} ms'}
 
     def get_publisher_handle_info(
         self,