| # 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._noprefix = False |
| |
| 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) |
| |
| # Check if this controller uses "noprefix" option |
| output = target.execute('mount | grep "{} "'.format(self.mount_name)) |
| if 'noprefix' in output: |
| self._noprefix = True |
| # self.logger.debug('Controller %s using "noprefix" option', |
| # self.kind) |
| |
| self.logger.debug('Controller %s mounted under: %s (noprefix=%s)', |
| self.kind, self.mount_point, self._noprefix) |
| |
| # 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), |
| as_root=True) |
| cgroups = [] |
| for cg in output.splitlines(): |
| 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.debug('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), as_root=True) |
| 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_util( |
| 'cgroups_get_attributes {} {}'.format( |
| self.directory, self.controller.kind), |
| as_root=True) |
| for res in output.splitlines(): |
| 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 |
| if self.controller._noprefix: |
| attr_name = '{}'.format(idx) |
| else: |
| attr_name = '{}.{}'.format(self.controller.kind, idx) |
| path = self.target.path.join(self.directory, attr_name) |
| |
| self.logger.debug('Set attribute [%s] to: %s"', |
| path, attrs[idx]) |
| |
| # Set the attribute value |
| try: |
| self.target.write_value(path, attrs[idx]) |
| except TargetError: |
| # Check if the error is due to a non-existing attribute |
| attrs = self.get() |
| if idx not in attrs: |
| raise ValueError('Controller [{}] does not provide attribute [{}]'\ |
| .format(self.controller.kind, attr_name)) |
| raise |
| |
| 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): |
| if not target.is_rooted: |
| return False |
| if target.file_exists('/proc/cgroups'): |
| return True |
| return target.config.has('cgroups') |
| |
| 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.debug('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)).splitlines()[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] |
| |
| def run_into(self, cgroup, cmdline): |
| """ |
| Run the specified command into the specified CGroup |
| """ |
| return self.target._execute_util( |
| 'cgroups_run_into {} {}'.format(cgroup, cmdline), |
| as_root=True) |
| |
| |
| def cgroups_tasks_move(self, srcg, dstg, exclude=''): |
| """ |
| Move all the tasks from the srcg CGroup to the dstg one. |
| A regexps of tasks names can be used to defined tasks which should not |
| be moved. |
| """ |
| return self.target._execute_util( |
| 'cgroups_tasks_move {} {} {}'.format(srcg, dstg, exclude), |
| as_root=True) |
| |