qemu-e2k/scripts/tracetool/backend/stderr.py
Dr. David Alan Gilbert dd9fe29c80 trace: Print PID and time in stderr traces
When debugging migration it's useful to know the PID of
each trace message so you can figure out if it came from the source
or the destination.

Printing the time makes it easy to do latency measurements or timings
between trace points.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-id: 1421746875-9962-1-git-send-email-dgilbert@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-02-06 10:27:22 +00:00

48 lines
1.3 KiB
Python

#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
Stderr built-in backend.
"""
__author__ = "Lluís Vilanova <vilanova@ac.upc.edu>"
__copyright__ = "Copyright 2012-2014, Lluís Vilanova <vilanova@ac.upc.edu>"
__license__ = "GPL version 2 or (at your option) any later version"
__maintainer__ = "Stefan Hajnoczi"
__email__ = "stefanha@linux.vnet.ibm.com"
from tracetool import out
PUBLIC = True
def generate_h_begin(events):
out('#include <stdio.h>',
'#include <sys/time.h>',
'#include <sys/types.h>',
'#include <unistd.h>',
'#include "trace/control.h"',
'')
def generate_h(event):
argnames = ", ".join(event.args.names())
if len(event.args) > 0:
argnames = ", " + argnames
out(' if (trace_event_get_state(%(event_id)s)) {',
' struct timeval _now;',
' gettimeofday(&_now, NULL);',
' fprintf(stderr, "%%d@%%zd.%%06zd:%(name)s " %(fmt)s "\\n",',
' getpid(),',
' (size_t)_now.tv_sec, (size_t)_now.tv_usec',
' %(argnames)s);',
' }',
event_id="TRACE_" + event.name.upper(),
name=event.name,
fmt=event.fmt.rstrip("\n"),
argnames=argnames)