mirror of
https://github.com/ARM-software/devlib.git
synced 2025-01-31 10:10:46 +00:00
9c9a74826a
This patch refactors the CGroup module to support multiple controllers.
The new interface is based on two main classes:
.:: Controller(kind)
Provides a wrapper class for a CGgroup controller of "kind".
At module initialization time, all the controller available in the
system are enumerated and a corresponding controller class created.
A valid reference to the Controller class for a specific CGroup
controller can be obtained using the controller(kind) method exposed
by the module, e.g. to get a reference to the CPUSET controller:
cpuset = target.cgroups.controller('cpuset')
.:: CGroup(name)
Provides a wrapper class for a CGroup of "name", i.e. a folder which
path is "name" relative to the controller mount point.
At module initialization time, the root control group for each
controller is created by the controller class.
A valid reference to a CGroup for a specific controller can be
obtained using the cgroup(name) method exposed by the controller
object, e.g. to get a reference to the "/LITTLE" cgroup of the
cpuset controller:
cpuset_littles = cpuset.cgroup('/LITTLE')
The CGroup object exposes simple get()/set() methods which allows to
read and configure all the supported attributes of a controller.
For example, to set the "cpus" of a cpuset control group:
cpuset_littles.set(cpus=[0,1])
NOTE: the set() method accepts a variable list of parameters which name
must match a valid (writable) attribute for that controller.
Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com>
282 lines
9.8 KiB
Python
282 lines
9.8 KiB
Python
# Copyright 2014-2015 ARM Limited
|
|
#
|
|
# Licensed under the Apache License, Version 2.0 (the "License");
|
|
# you may not use this file except in compliance with the License.
|
|
# You may obtain a copy of the License at
|
|
#
|
|
# http://www.apache.org/licenses/LICENSE-2.0
|
|
#
|
|
# Unless required by applicable law or agreed to in writing, software
|
|
# distributed under the License is distributed on an "AS IS" BASIS,
|
|
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
# See the License for the specific language governing permissions and
|
|
# limitations under the License.
|
|
#
|
|
# pylint: disable=attribute-defined-outside-init
|
|
import logging
|
|
from collections import namedtuple
|
|
|
|
from devlib.module import Module
|
|
from devlib.exception import TargetError
|
|
from devlib.utils.misc import list_to_ranges, isiterable
|
|
from devlib.utils.types import boolean
|
|
|
|
|
|
class Controller(object):
|
|
|
|
def __new__(cls, arg):
|
|
if isinstance(arg, cls):
|
|
return arg
|
|
else:
|
|
return object.__new__(cls, arg)
|
|
|
|
def __init__(self, kind):
|
|
self.mount_name = 'devlib_'+kind
|
|
self.kind = kind
|
|
self.target = None
|
|
|
|
self.logger = logging.getLogger('cgroups.'+self.kind)
|
|
self.mount_point = None
|
|
self._cgroups = {}
|
|
|
|
def probe(self, target):
|
|
try:
|
|
exists = target.execute('{} grep {} /proc/cgroups'\
|
|
.format(target.busybox, self.kind))
|
|
except TargetError:
|
|
return False
|
|
return True
|
|
|
|
def mount(self, target, mount_root):
|
|
|
|
mounted = target.list_file_systems()
|
|
if self.mount_name in [e.device for e in mounted]:
|
|
# Identify mount point if controller is already in use
|
|
self.mount_point = [
|
|
fs.mount_point
|
|
for fs in mounted
|
|
if fs.device == self.mount_name
|
|
][0]
|
|
else:
|
|
# Mount the controller if not already in use
|
|
self.mount_point = target.path.join(mount_root, self.mount_name)
|
|
target.execute('mkdir -p {} 2>/dev/null'\
|
|
.format(self.mount_point), as_root=True)
|
|
target.execute('mount -t cgroup -o {} {} {}'\
|
|
.format(self.kind,
|
|
self.mount_name,
|
|
self.mount_point),
|
|
as_root=True)
|
|
|
|
self.logger.info('Controller %s mounted under: %s',
|
|
self.kind, self.mount_point)
|
|
|
|
# Mark this contoller as available
|
|
self.target = target
|
|
|
|
# Create root control group
|
|
self.cgroup('/')
|
|
|
|
def cgroup(self, name):
|
|
if not self.target:
|
|
raise RuntimeError('CGroup creation failed: {} controller not mounted'\
|
|
.format(self.kind))
|
|
if name not in self._cgroups:
|
|
self._cgroups[name] = CGroup(self, name)
|
|
return self._cgroups[name]
|
|
|
|
def exists(self, name):
|
|
if not self.target:
|
|
raise RuntimeError('CGroup creation failed: {} controller not mounted'\
|
|
.format(self.kind))
|
|
if name not in self._cgroups:
|
|
self._cgroups[name] = CGroup(self, name, create=False)
|
|
return self._cgroups[name].existe()
|
|
|
|
def list_all(self):
|
|
self.logger.debug('Listing groups for %s controller', self.kind)
|
|
output = self.target.execute('{} find {} -type d'\
|
|
.format(self.target.busybox, self.mount_point))
|
|
cgroups = []
|
|
for cg in output.split('\n'):
|
|
cg = cg.replace(self.mount_point + '/', '/')
|
|
cg = cg.replace(self.mount_point, '/')
|
|
cg = cg.strip()
|
|
if cg == '':
|
|
continue
|
|
self.logger.debug('Populate %s cgroup: %s', self.kind, cg)
|
|
cgroups.append(cg)
|
|
return cgroups
|
|
|
|
def move_tasks(self, source, dest):
|
|
try:
|
|
srcg = self._cgroups[source]
|
|
dstg = self._cgroups[dest]
|
|
command = 'for task in $(cat {}); do echo $task>{}; done'
|
|
self.target.execute(command.format(srcg.tasks_file, dstg.tasks_file),
|
|
# this will always fail as some of the tasks
|
|
# are kthreads that cannot be migrated, but we
|
|
# don't care about those, so don't check exit
|
|
# code.
|
|
check_exit_code=False, as_root=True)
|
|
except KeyError as e:
|
|
raise ValueError('Unkown group: {}'.format(e))
|
|
|
|
def move_all_tasks_to(self, dest):
|
|
for cgroup in self._cgroups:
|
|
if cgroup != dest:
|
|
self.move_tasks(cgroup, dest)
|
|
|
|
class CGroup(object):
|
|
|
|
def __init__(self, controller, name, create=True):
|
|
self.logger = logging.getLogger('cgroups.' + controller.kind)
|
|
self.target = controller.target
|
|
self.controller = controller
|
|
self.name = name
|
|
|
|
# Control cgroup path
|
|
self.directory = controller.mount_point
|
|
if name != '/':
|
|
self.directory = self.target.path.join(controller.mount_point, name[1:])
|
|
|
|
# Setup path for tasks file
|
|
self.tasks_file = self.target.path.join(self.directory, 'tasks')
|
|
self.procs_file = self.target.path.join(self.directory, 'cgroup.procs')
|
|
|
|
if not create:
|
|
return
|
|
|
|
self.logger.info('Creating cgroup %s', self.directory)
|
|
self.target.execute('[ -d {0} ] || mkdir -p {0}'\
|
|
.format(self.directory), as_root=True)
|
|
|
|
def exists(self):
|
|
try:
|
|
self.target.execute('[ -d {0} ]'\
|
|
.format(self.directory))
|
|
return True
|
|
except TargetError:
|
|
return False
|
|
|
|
def get(self):
|
|
conf = {}
|
|
|
|
logging.debug('Reading %s attributes from:',
|
|
self.controller.kind)
|
|
logging.debug(' %s',
|
|
self.directory)
|
|
output = self.target.execute('{} grep \'\' {}/{}.*'.format(
|
|
self.target.busybox,
|
|
self.directory,
|
|
self.controller.kind))
|
|
for res in output.split('\n'):
|
|
if res.find(self.controller.kind) < 0:
|
|
continue
|
|
res = res.split('.')[1]
|
|
attr = res.split(':')[0]
|
|
value = res.split(':')[1]
|
|
conf[attr] = value
|
|
|
|
return conf
|
|
|
|
def set(self, **attrs):
|
|
for idx in attrs:
|
|
if isiterable(attrs[idx]):
|
|
attrs[idx] = list_to_ranges(attrs[idx])
|
|
# Build attribute path
|
|
path = '{}.{}'.format(self.controller.kind, idx)
|
|
path = self.target.path.join(self.directory, path)
|
|
|
|
self.logger.debug('Set attribute [%s] to: %s"',
|
|
path, attrs[idx])
|
|
|
|
# Set the attribute value
|
|
self.target.write_value(path, attrs[idx])
|
|
|
|
def get_tasks(self):
|
|
task_ids = self.target.read_value(self.tasks_file).split()
|
|
logging.debug('Tasks: %s', task_ids)
|
|
return map(int, task_ids)
|
|
|
|
def add_task(self, tid):
|
|
self.target.write_value(self.tasks_file, tid, verify=False)
|
|
|
|
def add_tasks(self, tasks):
|
|
for tid in tasks:
|
|
self.add_task(tid)
|
|
|
|
def add_proc(self, pid):
|
|
self.target.write_value(self.procs_file, pid, verify=False)
|
|
|
|
CgroupSubsystemEntry = namedtuple('CgroupSubsystemEntry', 'name hierarchy num_cgroups enabled')
|
|
|
|
class CgroupsModule(Module):
|
|
|
|
name = 'cgroups'
|
|
cgroup_root = '/sys/fs/cgroup'
|
|
|
|
@staticmethod
|
|
def probe(target):
|
|
return target.config.has('cgroups') and target.is_rooted
|
|
|
|
def __init__(self, target):
|
|
super(CgroupsModule, self).__init__(target)
|
|
|
|
self.logger = logging.getLogger('CGroups')
|
|
|
|
# Initialize controllers mount point
|
|
mounted = self.target.list_file_systems()
|
|
if self.cgroup_root not in [e.mount_point for e in mounted]:
|
|
self.target.execute('mount -t tmpfs {} {}'\
|
|
.format('cgroup_root',
|
|
self.cgroup_root),
|
|
as_root=True)
|
|
else:
|
|
self.logger.debug('cgroup_root already mounted at %s',
|
|
self.cgroup_root)
|
|
|
|
# Load list of available controllers
|
|
controllers = []
|
|
subsys = self.list_subsystems()
|
|
for (n, h, c, e) in subsys:
|
|
controllers.append(n)
|
|
self.logger.info('Available controllers: %s', controllers)
|
|
|
|
# Initialize controllers
|
|
self.controllers = {}
|
|
for idx in controllers:
|
|
controller = Controller(idx)
|
|
self.logger.debug('Init %s controller...', controller.kind)
|
|
if not controller.probe(self.target):
|
|
continue
|
|
try:
|
|
controller.mount(self.target, self.cgroup_root)
|
|
except TargetError:
|
|
message = 'cgroups {} controller is not supported by the target'
|
|
raise TargetError(message.format(controller.kind))
|
|
self.logger.debug('Controller %s enabled', controller.kind)
|
|
self.controllers[idx] = controller
|
|
|
|
def list_subsystems(self):
|
|
subsystems = []
|
|
for line in self.target.execute('{} cat /proc/cgroups'\
|
|
.format(self.target.busybox)).split('\n')[1:]:
|
|
line = line.strip()
|
|
if not line or line.startswith('#'):
|
|
continue
|
|
name, hierarchy, num_cgroups, enabled = line.split()
|
|
subsystems.append(CgroupSubsystemEntry(name,
|
|
int(hierarchy),
|
|
int(num_cgroups),
|
|
boolean(enabled)))
|
|
return subsystems
|
|
|
|
|
|
def controller(self, kind):
|
|
if kind not in self.controllers:
|
|
self.logger.warning('Controller %s not available', kind)
|
|
return None
|
|
return self.controllers[kind]
|
|
|