Allow the watcher binary to run even when there is no DPDK process running. In that case, wait for a suitable process to start and begin monitoring then. In case of disconnection, keep trying to reconnect and resume once reconnection succeeds.
Signed-off-by: Bruce Richardson <[email protected]> --- usertools/dpdk-telemetry-watcher.py | 46 +++++++++++++++++++++-------- 1 file changed, 34 insertions(+), 12 deletions(-) diff --git a/usertools/dpdk-telemetry-watcher.py b/usertools/dpdk-telemetry-watcher.py index 6beb67d29a..e5f470e08c 100755 --- a/usertools/dpdk-telemetry-watcher.py +++ b/usertools/dpdk-telemetry-watcher.py @@ -85,6 +85,12 @@ def create_telemetry_process(telemetry_script, args_list): text=True, bufsize=1, # Line buffered ) + + # Get and display the connected application name + if not print_connected_app(process): + return None + process.script = telemetry_script # Store script path for reference + process.args = args_list # Store args for reference return process except FileNotFoundError: print(f"Error: Python interpreter or script not found", file=sys.stderr) @@ -102,15 +108,28 @@ def query_telemetry(process, command): command: The telemetry command to send (e.g., "/info" or "/ethdev/stats,0") Returns: - dict: The parsed JSON response with the command wrapper stripped, + (process, dict): The process handle, in case of reconnection, and the + parsed JSON response with the command wrapper stripped, or None if there was an error """ # Send the command process.stdin.write(f"{command}\n") process.stdin.flush() - # Read the JSON response + # Read the JSON response, reconnecting if necessary response = process.stdout.readline() + while not response: + script = process.script + args_list = process.args + process = None + print("Application disconnected, retrying...", file=sys.stderr) + while not process: + time.sleep(1) + process = create_telemetry_process(script, args_list) + process.stdin.write(f"{command}\n") + process.stdin.flush() + response = process.stdout.readline() + try: data = json.loads(response) # When run non-interactively, the response is wrapped with the command @@ -119,11 +138,11 @@ def query_telemetry(process, command): # The response should have exactly one key which is the command if len(data) == 1: # Extract the value, ignoring the key - return next(iter(data.values())) + return (process, next(iter(data.values()))) else: - return data + return (process, data) except (json.JSONDecodeError, KeyError): - return None + return (None, None) def print_connected_app(process): @@ -132,11 +151,12 @@ def print_connected_app(process): Args: process: The subprocess.Popen handle to the telemetry process """ - info = query_telemetry(process, "/info") + process, info = query_telemetry(process, "/info") if info and "pid" in info: app_name = get_app_name(info["pid"]) if app_name: print(f'Connected to application: "{app_name}"') + return process def expand_shortcuts(process, stat_specs): @@ -169,7 +189,7 @@ def expand_shortcuts(process, stat_specs): field = field_map.get(field, field) # Get list of ethernet devices - port_list = query_telemetry(process, "/ethdev/list") + process, port_list = query_telemetry(process, "/ethdev/list") if not isinstance(port_list, list): print(f"Error: Failed to get ethernet device list", file=sys.stderr) return None @@ -216,7 +236,7 @@ def validate_stats(process, stat_specs): return None, None # Query the stat once to validate it exists and is numeric - data = query_telemetry(process, command) + process, data = query_telemetry(process, command) if not isinstance(data, dict): print(f"Error: Command '{command}' did not return a dictionary", file=sys.stderr) return None, None @@ -276,7 +296,7 @@ def monitor_stats(process, args): current_values = [] total = 0 for i, (spec, command, field) in enumerate(parsed_specs): - data = query_telemetry(process, command) + process, data = query_telemetry(process, command) current_value = data[field] current_values.append(current_value) @@ -387,9 +407,11 @@ def main(): # Run dpdk-telemetry.py with pipes for stdin and stdout process = create_telemetry_process(telemetry_script, args_list) - - # Get and display the connected application name - print_connected_app(process) + if not process: + print("Waiting for connection to DPDK application...", file=sys.stderr) + while not process: + time.sleep(1) + process = create_telemetry_process(telemetry_script, args_list) # Monitor the requested statistics monitor_stats(process, args) -- 2.51.0
