diff --git a/tracetools_trace/tools/args.py b/tracetools_trace/tools/args.py new file mode 100644 index 0000000..5959f8c --- /dev/null +++ b/tracetools_trace/tools/args.py @@ -0,0 +1,51 @@ +import argparse +import time + +from . import names + + +class DefaultArgValueCompleter: + """Callable returning an arg's default value.""" + + def __init__(self, arg): + default = arg.default + self.list = default if isinstance(default, list) else [default] + + def __call__(self, **kwargs): + return self.list + + +def parse_args(): + """ + Parse args for tracing. + """ + parser = argparse.ArgumentParser(description='Setup and launch an LTTng tracing session.') + add_arguments(parser) + return parser.parse_args() + + +def add_arguments(parser): + parser.add_argument( + '--session-name', '-s', dest='session_name', + default=f'session-{time.strftime("%Y%m%d%H%M%S")}', + help='the name of the tracing session (default: session-YYYYMMDDHHMMSS)') + parser.add_argument( + '--path', '-p', dest='path', + default='/tmp', + help='path of the base directory for trace data (default: %(default)s)') + arg = parser.add_argument( + '--ust', '-u', nargs='*', dest='events_ust', default=names.DEFAULT_EVENTS_ROS, + help='the ROS UST events to enable (default: all events) ' + '[to disable all UST events, ' + 'provide this flag without any event name]') + arg.completer = DefaultArgValueCompleter(arg) + arg = parser.add_argument( + '--kernel', '-k', nargs='*', dest='events_kernel', + default=names.DEFAULT_EVENTS_KERNEL, + help='the kernel events to enable (default: all events) ' + '[to disable all UST events, ' + 'provide this flag without any event name]') + arg.completer = DefaultArgValueCompleter(arg) + parser.add_argument( + '--list', '-l', dest='list', action='store_true', + help='display lists of enabled events (default: %(default)s)') diff --git a/tracetools_trace/tools/lttng.py b/tracetools_trace/tools/lttng.py index 60684c5..6c86b37 100644 --- a/tracetools_trace/tools/lttng.py +++ b/tracetools_trace/tools/lttng.py @@ -15,13 +15,43 @@ from .names import ( # noqa: E402 ) -def lttng_setup( +def lttng_init( session_name: str, full_path: str, ros_events: List[str] = DEFAULT_EVENTS_ROS, kernel_events: List[str] = DEFAULT_EVENTS_KERNEL, - context_names: List[str] = DEFAULT_CONTEXT, + context_names: List[str] = DEFAULT_CONTEXT ) -> None: + """ + Set up and start LTTng session. + + :param session_name: the name of the session + :param full_path: the full path to the main directory to write trace data to + :param ros_events: list of ROS events to enable + :param kernel_events: list of kernel events to enable + :param context_names: list of context elements to enable + """ + _lttng_setup(session_name, full_path, ros_events, kernel_events, context_names) + _lttng_start(session_name) + + +def lttng_fini(session_name: str) -> None: + """ + Stop and destroy LTTng session. + + :param session_name: the name of the session + """ + _lttng_stop(session_name) + _lttng_destroy(session_name) + + +def _lttng_setup( + session_name: str, + full_path: str, + ros_events: List[str] = DEFAULT_EVENTS_ROS, + kernel_events: List[str] = DEFAULT_EVENTS_KERNEL, + context_names: List[str] = DEFAULT_CONTEXT + ) -> None: """ Set up LTTng session, with events and context. @@ -83,7 +113,7 @@ def lttng_setup( _add_context(enabled_handles, context_list) -def lttng_start(session_name: str) -> None: +def _lttng_start(session_name: str) -> None: """ Start LTTng session, and check for errors. @@ -94,7 +124,7 @@ def lttng_start(session_name: str) -> None: raise RuntimeError(f'failed to start tracing: {lttng.strerror(result)}') -def lttng_stop(session_name: str) -> None: +def _lttng_stop(session_name: str) -> None: """ Stop LTTng session, and check for errors. @@ -105,7 +135,7 @@ def lttng_stop(session_name: str) -> None: raise RuntimeError(f'failed to stop tracing: {lttng.strerror(result)}') -def lttng_destroy(session_name: str) -> None: +def _lttng_destroy(session_name: str) -> None: """ Destroy LTTng session, and check for errors. diff --git a/tracetools_trace/trace.py b/tracetools_trace/trace.py index fe7269f..16639dc 100644 --- a/tracetools_trace/trace.py +++ b/tracetools_trace/trace.py @@ -1,72 +1,41 @@ #!/usr/bin/env python3 # Entrypoint/script to setup and start an LTTng tracing session -import argparse import os -import time +from tracetools_trace.tools import args from tracetools_trace.tools import lttng from tracetools_trace.tools import names -def parse_args(): - parser = argparse.ArgumentParser(description='Setup and launch an LTTng tracing session.') - parser.add_argument( - '--session-name', '-s', dest='session_name', - default=f'session-{time.strftime("%Y%m%d%H%M%S")}', - help='the name of the tracing session (default: session-YYYYMMDDHHMMSS)') - parser.add_argument( - '--path', '-p', dest='path', - default='/tmp', - help='path of the base directory for trace data (default: %(default)s)') - parser.add_argument( - '--ust', '-u', nargs='*', dest='events_ust', default=names.DEFAULT_EVENTS_ROS, - help='the ROS UST events to enable (default: all events) ' - '[to disable all UST events, ' - 'provide this flag without any event name]') - parser.add_argument( - '--kernel', '-k', nargs='*', dest='events_kernel', - default=names.DEFAULT_EVENTS_KERNEL, - help='the kernel events to enable (default: all events) ' - '[to disable all UST events, ' - 'provide this flag without any event name]') - parser.add_argument( - '--list', '-l', dest='list', action='store_true', - help='display lists of enabled events (default: %(default)s)') - return parser.parse_args() - - def main(): - args = parse_args() + params = args.parse_args() - session_name = args.session_name - base_path = args.path + session_name = params.session_name + base_path = params.path full_path = os.path.join(base_path, session_name) - ros_events = args.events_ust - kernel_events = args.events_kernel + ros_events = params.events_ust + kernel_events = params.events_kernel ust_enabled = len(ros_events) > 0 kernel_enabled = len(kernel_events) > 0 if ust_enabled: print(f'UST tracing enabled ({len(ros_events)} events)') - if args.list: + if params.list: print(f'\tevents: {ros_events}') else: print('UST tracing disabled') if kernel_enabled: print(f'kernel tracing enabled ({len(kernel_events)} events)') - if args.list: + if params.list: print(f'\tevents: {kernel_events}') else: print('kernel tracing disabled') - lttng.lttng_setup(session_name, full_path, ros_events=ros_events, kernel_events=kernel_events) print(f'writting tracing session to: {full_path}') - input('press enter to start...') - lttng.lttng_start(session_name) + lttng.lttng_init(session_name, full_path, ros_events=ros_events, kernel_events=kernel_events) input('press enter to stop...') print('stopping & destroying tracing session') - lttng.lttng_stop(session_name) - lttng.lttng_destroy(session_name) + lttng.lttng_fini(session_name)