"""
perf is a tool included in the linux kernel tree that
supports functionality similar to oprofile and more.
@see: http://lwn.net/Articles/310260/
"""
import logging
import os
import signal
import stat
import subprocess
from autotest.client import profiler, os_dep, utils
[docs]class perf(profiler.profiler):
version = 1
[docs] def initialize(self, events=["cycles", "instructions"], trace=False, **dargs):
if type(events) == str:
self.events = [events]
else:
self.events = events
self.trace = trace
self.perf_bin = os_dep.command('perf')
perf_help = utils.run('%s report help' % self.perf_bin,
ignore_status=True).stderr
self.sort_keys = None
for line in perf_help.split('\n'):
a = "sort by key(s):"
if a in line:
line = line.replace(a, "")
self.sort_keys = [k.rstrip(",") for k in line.split() if
k.rstrip(",") != 'dso']
if not self.sort_keys:
self.sort_keys = ['comm', 'cpu']
[docs] def start(self, test):
self.logfile = os.path.join(test.profdir, "perf")
cmd = ("exec %s record -a -o %s" %
(self.perf_bin, self.logfile))
if "parent" in self.sort_keys:
cmd += " -g"
if self.trace:
cmd += " -R"
for event in self.events:
cmd += " -e %s" % event
self._process = subprocess.Popen(cmd, shell=True,
stderr=subprocess.STDOUT)
[docs] def stop(self, test):
os.kill(self._process.pid, signal.SIGINT)
self._process.wait()
[docs] def report(self, test):
for key in self.sort_keys:
reportfile = os.path.join(test.profdir, '%s.comm' % key)
cmd = ("%s report -i %s --sort %s,dso" % (self.perf_bin,
self.logfile,
key))
outfile = open(reportfile, 'w')
p = subprocess.Popen(cmd, shell=True, stdout=outfile,
stderr=subprocess.STDOUT)
p.wait()
if self.trace:
tracefile = os.path.join(test.profdir, 'trace')
cmd = ("%s script -i %s" % (self.perf_bin, self.logfile,))
outfile = open(tracefile, 'w')
p = subprocess.Popen(cmd, shell=True, stdout=outfile,
stderr=subprocess.STDOUT)
p.wait()
# The raw detailed perf output is HUGE. We cannot store it by default.
perf_log_size = os.stat(self.logfile)[stat.ST_SIZE]
logging.info('Removing %s after generating reports (saving %s bytes).',
self.logfile, perf_log_size)
os.unlink(self.logfile)