#!/usr/bin/python
# -*- coding: utf-8 -*-
"""
Helpers for cgroup testing.
@copyright: 2011 Red Hat Inc.
@author: Lukas Doktor <ldoktor@redhat.com>
"""
import os, logging, subprocess, time, shutil
from tempfile import mkdtemp
from autotest_lib.client.bin import utils
from autotest_lib.client.common_lib import error
class Cgroup(object):
"""
Cgroup handling class.
"""
def __init__(self, module, _client):
"""
Constructor
@param module: Name of the cgroup module
@param _client: Test script pwd + name
"""
self.module = module
self._client = _client
self.root = None
def initialize(self, modules):
"""
Initializes object for use.
@param modules: Array of all available cgroup modules.
@return: 0 when PASSED.
"""
self.root = modules.get_pwd(self.module)
if self.root:
return 0
else:
logging.error("cg.initialize(): Module %s not found", self.module)
return -1
return 0
def mk_cgroup(self, root=None):
"""
Creates new temporary cgroup
@param root: where to create this cgroup (default: self.root)
@return: 0 when PASSED
"""
try:
if root:
pwd = mkdtemp(prefix='cgroup-', dir=root) + '/'
else:
pwd = mkdtemp(prefix='cgroup-', dir=self.root) + '/'
except Exception, inst:
logging.error("cg.mk_cgroup(): %s" , inst)
return None
return pwd
def rm_cgroup(self, pwd, supress=False):
"""
Removes cgroup.
@param pwd: cgroup directory.
@param supress: supress output.
@return: 0 when PASSED
"""
try:
os.rmdir(pwd)
except Exception, inst:
if not supress:
logging.error("cg.rm_cgroup(): %s" , inst)
return -1
return 0
def test(self, cmd):
"""
Executes cgroup_client.py with cmd parameter.
@param cmd: command to be executed
@return: subprocess.Popen() process
"""
logging.debug("cg.test(): executing paralel process '%s'", cmd)
cmd = self._client + ' ' + cmd
process = subprocess.Popen(cmd, shell=True, stdin=subprocess.PIPE,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE, close_fds=True)
return process
def is_cgroup(self, pid, pwd):
"""
Checks if the 'pid' process is in 'pwd' cgroup
@param pid: pid of the process
@param pwd: cgroup directory
@return: 0 when is 'pwd' member
"""
if open(pwd + '/tasks').readlines().count("%d\n" % pid) > 0:
return 0
else:
return -1
def is_root_cgroup(self, pid):
"""
Checks if the 'pid' process is in root cgroup (WO cgroup)
@param pid: pid of the process
@return: 0 when is 'root' member
"""
return self.is_cgroup(pid, self.root)
def set_cgroup(self, pid, pwd):
"""
Sets cgroup membership
@param pid: pid of the process
@param pwd: cgroup directory
@return: 0 when PASSED
"""
try:
open(pwd+'/tasks', 'w').write(str(pid))
except Exception, inst:
logging.error("cg.set_cgroup(): %s" , inst)
return -1
if self.is_cgroup(pid, pwd):
logging.error("cg.set_cgroup(): Setting %d pid into %s cgroup "
"failed", pid, pwd)
return -1
else:
return 0
def set_root_cgroup(self, pid):
"""
Resets the cgroup membership (sets to root)
@param pid: pid of the process
@return: 0 when PASSED
"""
return self.set_cgroup(pid, self.root)
def get_prop(self, prop, pwd=None, supress=False):
"""
Gets one line of the property value
@param prop: property name (file)
@param pwd: cgroup directory
@param supress: supress the output
@return: String value or None when FAILED
"""
tmp = self.get_property(prop, pwd, supress)
if tmp:
if tmp[0][-1] == '\n':
tmp[0] = tmp[0][:-1]
return tmp[0]
else:
return None
def get_property(self, prop, pwd=None, supress=False):
"""
Gets the property value
@param prop: property name (file)
@param pwd: cgroup directory
@param supress: supress the output
@return: [] values or None when FAILED
"""
if pwd == None:
pwd = self.root
try:
ret = open(pwd+prop, 'r').readlines()
except Exception, inst:
ret = None
if not supress:
logging.error("cg.get_property(): %s" , inst)
return ret
def set_prop(self, prop, value, pwd=None, check=True):
"""
Sets the one-line property value concerning the K,M,G postfix
@param prop: property name (file)
@param value: desired value
@param pwd: cgroup directory
@param check: check the value after setup
@return: 0 when PASSED
"""
_value = value
try:
value = str(value)
if value[-1] == '\n':
value = value[:-1]
if value[-1] == 'K':
value = int(value[:-1]) * 1024
elif value[-1] == 'M':
value = int(value[:-1]) * 1048576
elif value[-1] == 'G':
value = int(value[:-1]) * 1073741824
except:
logging.error("cg.set_prop() fallback into cg.set_property.")
value = _value
return self.set_property(prop, value, pwd, check)
def set_property(self, prop, value, pwd=None, check=True):
"""
Sets the property value
@param prop: property name (file)
@param value: desired value
@param pwd: cgroup directory
@param check: check the value after setup
@return: 0 when PASSED
"""
value = str(value)
if pwd == None:
pwd = self.root
try:
open(pwd+prop, 'w').write(value)
except Exception, inst:
logging.error("cg.set_property(): %s" , inst)
return -1
if check:
# Get the first line - '\n'
_value = self.get_property(prop, pwd)[0][:-1]
if value != _value:
logging.error("cg.set_property(): Setting failed: desired = %s,"
" real value = %s", value, _value)
return -1
return 0
def smoke_test(self):
"""
Smoke test
Module independent basic tests
"""
part = 0
pwd = self.mk_cgroup()
if pwd == None:
logging.error("cg.smoke_test[%d]: Can't create cgroup", part)
return -1
part += 1
ps = self.test("smoke")
if ps == None:
logging.error("cg.smoke_test[%d]: Couldn't create process", part)
return -1
part += 1
if (ps.poll() != None):
logging.error("cg.smoke_test[%d]: Process died unexpectidly", part)
return -1
# New process should be a root member
part += 1
if self.is_root_cgroup(ps.pid):
logging.error("cg.smoke_test[%d]: Process is not a root member",
part)
return -1
# Change the cgroup
part += 1
if self.set_cgroup(ps.pid, pwd):
logging.error("cg.smoke_test[%d]: Could not set cgroup", part)
return -1
# Try to remove used cgroup
part += 1
if self.rm_cgroup(pwd, supress=True) == 0:
logging.error("cg.smoke_test[%d]: Unexpected successful deletion of"
" the used cgroup", part)
return -1
# Return the process into the root cgroup
part += 1
if self.set_root_cgroup(ps.pid):
logging.error("cg.smoke_test[%d]: Could not return the root cgroup "
"membership", part)
return -1
# It should be safe to remove the cgroup now
part += 1
if self.rm_cgroup(pwd):
logging.error("cg.smoke_test[%d]: Can't remove cgroup directory",
part)
return -1
# Finish the process
part += 1
ps.stdin.write('\n')
time.sleep(2)
if (ps.poll() == None):
logging.error("cg.smoke_test[%d]: Process is not finished", part)
return -1
return 0
class CgroupModules(object):
"""
Handles the list of different cgroup filesystems.
"""
def __init__(self):
self.modules = []
self.modules.append([])
self.modules.append([])
self.modules.append([])
self.mountdir = mkdtemp(prefix='cgroup-') + '/'
def init(self, _modules):
"""
Checks the mounted modules and if necessary mounts them into tmp
mountdir.
@param _modules: Desired modules.
@return: Number of initialized modules.
"""
logging.debug("Desired cgroup modules: %s", _modules)
mounts = []
fp = open('/proc/mounts', 'r')
line = fp.readline().split()
while line:
if line[2] == 'cgroup':
mounts.append(line)
line = fp.readline().split()
fp.close()
for module in _modules:
# Is it already mounted?
i = False
for mount in mounts:
if mount[3].find(module) != -1:
self.modules[0].append(module)
self.modules[1].append(mount[1] + '/')
self.modules[2].append(False)
i = True
break
if not i:
# Not yet mounted
os.mkdir(self.mountdir + module)
cmd = ('mount -t cgroup -o %s %s %s' %
(module, module, self.mountdir + module))
try:
utils.run(cmd)
self.modules[0].append(module)
self.modules[1].append(self.mountdir + module)
self.modules[2].append(True)
except error.CmdError:
logging.info("Cgroup module '%s' not available", module)
logging.debug("Initialized cgroup modules: %s", self.modules[0])
return len(self.modules[0])
def cleanup(self):
"""
Unmount all cgroups and remove the mountdir.
"""
for i in range(len(self.modules[0])):
if self.modules[2][i]:
utils.system('umount %s -l' % self.modules[1][i],
ignore_status=True)
shutil.rmtree(self.mountdir)
def get_pwd(self, module):
"""
Returns the mount directory of 'module'
@param module: desired module (memory, ...)
@return: mount directory of 'module' or None
"""
try:
i = self.modules[0].index(module)
except Exception, inst:
logging.error("module %s not found: %s", module, inst)
return None
return self.modules[1][i]