def __init__(self,
trace_events,
trace_output_dir,
trace_name="bioflow_trace"):
if type(trace_events) is str:
trace_events = [trace_events]
self.trace_events = trace_events
user = getpass.getuser()
trace_name = "{name}_{user}".format(name=trace_name, user=user)
self.sess_name = trace_name
domain = lttng.Domain()
domain.type = lttng.DOMAIN_UST
handle = lttng.Handle(domain=domain, session_name=trace_name)
self.domain = domain
self.handle = handle
new_handle = trace_output_dir
count = 0
while os.path.exists(new_handle):
new_handle = "{trace_dir}_{cnt}".format(trace_dir=trace_output_dir,
cnt=count)
count += 1
trace_output_dir = new_handle
os.makedirs(name=trace_output_dir, exist_ok=False)
self.outdir = trace_output_dir
curr_sessions = lttng.list_sessions()
if trace_name in curr_sessions:
lttng.destroy(trace_name) # note: this doesn't delete any files
def _create_handle(session_name: str, domain: lttng.Domain) -> lttng.Handle:
"""
Create a handle for a given session name and a domain, and check for errors.
:param session_name: the name of the session
:param domain: the domain to be used
:return: the handle
"""
handle = None
handle = lttng.Handle(session_name, domain)
if handle is None:
raise RuntimeError('handle creation failed')
return handle
def lttng_start(events=["*"], domain_type=lttng.DOMAIN_UST):
if lttng.session_daemon_alive() == 0:
daemon_cmd = "lttng-sessiond --background"
daemon_cmd += " --pidfile " + sessiond_pidfile
subprocess.check_call(daemon_cmd,
shell=True,
stdout=sessiond_logfile,
stderr=sessiond_logfile)
lttng.destroy(session_name)
ret = lttng.create_snapshot(session_name, trace_path)
if ret < 0:
raise RuntimeError("LTTng: " + lttng.strerror(ret))
domain = lttng.Domain()
domain.type = domain_type
channel = lttng.Channel()
channel.name = "channel0"
lttng.channel_set_default_attr(domain, channel.attr)
han = lttng.Handle(session_name, domain)
if han is None:
raise RuntimeError("LTTng: failed to create handle")
ret = lttng.enable_channel(han, channel)
if ret < 0:
raise RuntimeError("LTTng: " + lttng.strerror(ret))
for name in events:
event = lttng.Event()
event.name = name
event.type = lttng.EVENT_TRACEPOINT
event.loglevel = lttng.EVENT_LOGLEVEL_ALL
ret = lttng.enable_event(han, event, channel.name)
if ret < 0:
raise RuntimeError("LTTng: " + lttng.strerror(ret))
ret = lttng.start(session_name)
if ret < 0:
raise RuntimeError("LTTng: " + lttng.strerror(ret))
# LTTNG-TOOLS
# Making sure session does not already exist
lttng.destroy(ses_name)
# Creating a new session and handle
ret = lttng.create(ses_name, trace_path)
if ret < 0:
raise LTTngError(lttng.strerror(ret))
domain = lttng.Domain()
domain.type = lttng.DOMAIN_KERNEL
han = None
han = lttng.Handle(ses_name, domain)
if han is None:
raise LTTngError("Handle not created")
# Enabling all events
event = lttng.Event()
event.type = lttng.EVENT_ALL
event.loglevel_type = lttng.EVENT_LOGLEVEL_ALL
ret = lttng.enable_event(han, event, None)
if ret < 0:
raise LTTngError(lttng.strerror(ret))
# Start, wait, stop
ret = lttng.start(ses_name)
if ret < 0:
raise LTTngError(lttng.strerror(ret))