from . import base
from .decorators import *
import tuned.logs
from tuned.utils.commands import commands
import tuned.consts as consts
import os
import struct
import errno
import platform
import procfs
log = tuned.logs.get()
# TODO: force_latency -> command
# intel_pstate
class CPULatencyPlugin(base.Plugin):
"""
Plugin for tuning CPU options. Powersaving, governor, required latency, etc.
"""
def __init__(self, *args, **kwargs):
super(CPULatencyPlugin, self).__init__(*args, **kwargs)
self._has_pm_qos = True
self._arch = "x86_64"
self._is_x86 = False
self._is_intel = False
self._is_amd = False
self._has_energy_perf_bias = False
self._has_intel_pstate = False
self._min_perf_pct_save = None
self._max_perf_pct_save = None
self._no_turbo_save = None
self._governors_map = {}
self._cmd = commands()
def _init_devices(self):
self._devices_supported = True
self._free_devices = set()
# current list of devices
for device in self._hardware_inventory.get_devices("cpu"):
self._free_devices.add(device.sys_name)
self._assigned_devices = set()
def _get_device_objects(self, devices):
return [self._hardware_inventory.get_device("cpu", x) for x in devices]
@classmethod
def _get_config_options(self):
return {
"load_threshold" : 0.2,
"latency_low" : 100,
"latency_high" : 1000,
"force_latency" : None,
"governor" : None,
"sampling_down_factor" : None,
"energy_perf_bias" : None,
"min_perf_pct" : None,
"max_perf_pct" : None,
"no_turbo" : None,
}
def _check_arch(self):
intel_archs = [ "x86_64", "i686", "i585", "i486", "i386" ]
self._arch = platform.machine()
if self._arch in intel_archs:
# Possible other x86 vendors (from arch/x86/kernel/cpu/*):
# "CentaurHauls", "CyrixInstead", "Geode by NSC", "HygonGenuine", "GenuineTMx86",
# "TransmetaCPU", "UMC UMC UMC"
cpu = procfs.cpuinfo()
vendor = cpu.tags.get("vendor_id")
if vendor is "GenuineIntel":
self._is_intel = True
elif vendor is "AuthenticAMD" or vendor is "HygonGenuine":
self._is_amd = True
else:
# We always assign Intel, unless we know better
self._is_intel = True
log.info("We are running on an x86 %s platform" % vendor)
else:
log.info("We are running on %s (non x86)" % self._arch)
if self._is_intel is True:
# Check for x86_energy_perf_policy, ignore if not available / supported
self._check_energy_perf_bias()
# Check for intel_pstate
self._check_intel_pstate()
def _check_energy_perf_bias(self):
self._has_energy_perf_bias = False
retcode_unsupported = 1
retcode = self._cmd.execute(["x86_energy_perf_policy", "-r"], no_errors = [errno.ENOENT, retcode_unsupported])[0]
if retcode == 0:
self._has_energy_perf_bias = True
elif retcode < 0:
log.warning("unable to run x86_energy_perf_policy tool, ignoring CPU energy performance bias, is the tool installed?")
else:
log.warning("your CPU doesn't support MSR_IA32_ENERGY_PERF_BIAS, ignoring CPU energy performance bias")
def _check_intel_pstate(self):
self._has_intel_pstate = os.path.exists("/sys/devices/system/cpu/intel_pstate")
if self._has_intel_pstate:
log.info("intel_pstate detected")
def _is_cpu_online(self, device):
sd = str(device)
return self._cmd.is_cpu_online(str(device).replace("cpu", ""))
def _cpu_has_scaling_governor(self, device):
return os.path.exists("/sys/devices/system/cpu/%s/cpufreq/scaling_governor" % device)
def _check_cpu_can_change_governor(self, device):
if not self._is_cpu_online(device):
log.debug("'%s' is not online, skipping" % device)
return False
if not self._cpu_has_scaling_governor(device):
log.debug("there is no scaling governor fo '%s', skipping" % device)
return False
return True
def _instance_init(self, instance):
instance._has_static_tuning = True
instance._has_dynamic_tuning = False
# only the first instance of the plugin can control the latency
if list(self._instances.values())[0] == instance:
instance._first_instance = True
try:
self._cpu_latency_fd = os.open(consts.PATH_CPU_DMA_LATENCY, os.O_WRONLY)
except OSError:
log.error("Unable to open '%s', disabling PM_QoS control" % consts.PATH_CPU_DMA_LATENCY)
self._has_pm_qos = False
self._latency = None
if instance.options["force_latency"] is None:
instance._load_monitor = self._monitors_repository.create("load", None)
instance._has_dynamic_tuning = True
else:
instance._load_monitor = None
self._check_arch()
else:
instance._first_instance = False
log.info("Latency settings from non-first CPU plugin instance '%s' will be ignored." % instance.name)
instance._first_device = list(instance.assigned_devices)[0]
def _instance_cleanup(self, instance):
if instance._first_instance:
if self._has_pm_qos:
os.close(self._cpu_latency_fd)
if instance._load_monitor is not None:
self._monitors_repository.delete(instance._load_monitor)
def _get_intel_pstate_attr(self, attr):
return self._cmd.read_file("/sys/devices/system/cpu/intel_pstate/%s" % attr, None).strip()
def _set_intel_pstate_attr(self, attr, val):
if val is not None:
self._cmd.write_to_file("/sys/devices/system/cpu/intel_pstate/%s" % attr, val)
def _getset_intel_pstate_attr(self, attr, value):
if value is None:
return None
v = self._get_intel_pstate_attr(attr)
self._set_intel_pstate_attr(attr, value)
return v
def _instance_apply_static(self, instance):
super(CPULatencyPlugin, self)._instance_apply_static(instance)
if not instance._first_instance:
return
force_latency_value = instance.options["force_latency"]
if force_latency_value is not None:
self._set_latency(force_latency_value)
if self._has_intel_pstate:
self._min_perf_pct_save = self._getset_intel_pstate_attr("min_perf_pct", instance.options["min_perf_pct"])
self._max_perf_pct_save = self._getset_intel_pstate_attr("max_perf_pct", instance.options["max_perf_pct"])
self._no_turbo_save = self._getset_intel_pstate_attr("no_turbo", instance.options["no_turbo"])
def _instance_unapply_static(self, instance, full_rollback = False):
super(CPULatencyPlugin, self)._instance_unapply_static(instance, full_rollback)
if instance._first_instance and self._has_intel_pstate:
self._set_intel_pstate_attr("min_perf_pct", self._min_perf_pct_save)
self._set_intel_pstate_attr("max_perf_pct", self._max_perf_pct_save)
self._set_intel_pstate_attr("no_turbo", self._no_turbo_save)
def _instance_apply_dynamic(self, instance, device):
self._instance_update_dynamic(instance, device)
def _instance_update_dynamic(self, instance, device):
assert(instance._first_instance)
if device != instance._first_device:
return
load = instance._load_monitor.get_load()["system"]
if load < instance.options["load_threshold"]:
self._set_latency(instance.options["latency_high"])
else:
self._set_latency(instance.options["latency_low"])
def _instance_unapply_dynamic(self, instance, device):
pass
def _set_latency(self, latency):
latency = int(latency)
if self._has_pm_qos and self._latency != latency:
log.info("setting new cpu latency %d" % latency)
latency_bin = struct.pack("i", latency)
os.write(self._cpu_latency_fd, latency_bin)
self._latency = latency
def _get_available_governors(self, device):
return self._cmd.read_file("/sys/devices/system/cpu/%s/cpufreq/scaling_available_governors" % device).strip().split()
@command_set("governor", per_device=True)
def _set_governor(self, governors, device, sim):
if not self._check_cpu_can_change_governor(device):
return None
governors = str(governors)
governors = governors.split("|")
governors = [governor.strip() for governor in governors]
for governor in governors:
if len(governor) == 0:
log.error("The 'governor' option contains an empty value.")
return None
available_governors = self._get_available_governors(device)
for governor in governors:
if governor in available_governors:
if not sim:
log.info("setting governor '%s' on cpu '%s'"
% (governor, device))
self._cmd.write_to_file("/sys/devices/system/cpu/%s/cpufreq/scaling_governor"
% device, governor)
break
elif not sim:
log.debug("Ignoring governor '%s' on cpu '%s', it is not supported"
% (governor, device))
else:
log.warn("None of the scaling governors is supported: %s"
% ", ".join(governors))
governor = None
return governor
@command_get("governor")
def _get_governor(self, device, ignore_missing=False):
governor = None
if not self._check_cpu_can_change_governor(device):
return None
data = self._cmd.read_file("/sys/devices/system/cpu/%s/cpufreq/scaling_governor" % device, no_error=ignore_missing).strip()
if len(data) > 0:
governor = data
if governor is None:
log.error("could not get current governor on cpu '%s'" % device)
return governor
def _sampling_down_factor_path(self, governor = "ondemand"):
return "/sys/devices/system/cpu/cpufreq/%s/sampling_down_factor" % governor
@command_set("sampling_down_factor", per_device = True, priority = 10)
def _set_sampling_down_factor(self, sampling_down_factor, device, sim):
val = None
# hack to clear governors map when the profile starts unloading
# TODO: this should be handled better way, by e.g. currently non-implemented
# Plugin.profile_load_finished() method
if device in self._governors_map:
self._governors_map.clear()
self._governors_map[device] = None
governor = self._get_governor(device)
if governor is None:
log.debug("ignoring sampling_down_factor setting for CPU '%s', cannot match governor" % device)
return None
if governor not in list(self._governors_map.values()):
self._governors_map[device] = governor
path = self._sampling_down_factor_path(governor)
if not os.path.exists(path):
log.debug("ignoring sampling_down_factor setting for CPU '%s', governor '%s' doesn't support it" % (device, governor))
return None
val = str(sampling_down_factor)
if not sim:
log.info("setting sampling_down_factor to '%s' for governor '%s'" % (val, governor))
self._cmd.write_to_file(path, val)
return val
@command_get("sampling_down_factor")
def _get_sampling_down_factor(self, device, ignore_missing=False):
governor = self._get_governor(device, ignore_missing=ignore_missing)
if governor is None:
return None
path = self._sampling_down_factor_path(governor)
if not os.path.exists(path):
return None
return self._cmd.read_file(path).strip()
def _try_set_energy_perf_bias(self, cpu_id, value):
(retcode, out, err_msg) = self._cmd.execute(
["x86_energy_perf_policy",
"-c", cpu_id,
str(value)
],
return_err = True)
return (retcode, err_msg)
@command_set("energy_perf_bias", per_device=True)
def _set_energy_perf_bias(self, energy_perf_bias, device, sim):
if not self._is_cpu_online(device):
log.debug("%s is not online, skipping" % device)
return None
if self._has_energy_perf_bias:
if not sim:
cpu_id = device.lstrip("cpu")
vals = energy_perf_bias.split('|')
for val in vals:
val = val.strip()
log.debug("Trying to set energy_perf_bias to '%s' on cpu '%s'"
% (val, device))
(retcode, err_msg) = self._try_set_energy_perf_bias(
cpu_id, val)
if retcode == 0:
log.info("energy_perf_bias successfully set to '%s' on cpu '%s'"
% (val, device))
break
elif retcode < 0:
log.error("Failed to set energy_perf_bias: %s"
% err_msg)
break
else:
log.debug("Could not set energy_perf_bias to '%s' on cpu '%s', trying another value"
% (val, device))
else:
log.error("Failed to set energy_perf_bias on cpu '%s'. Is the value in the profile correct?"
% device)
return str(energy_perf_bias)
else:
return None
def _try_parse_num(self, s):
try:
v = int(s)
except ValueError as e:
try:
v = int(s, 16)
except ValueError as e:
v = s
return v
# Before Linux 4.13
def _energy_perf_policy_to_human(self, s):
return {0:"performance", 6:"normal", 15:"powersave"}.get(self._try_parse_num(s), s)
# Since Linux 4.13
def _energy_perf_policy_to_human_v2(self, s):
return {0:"performance",
4:"balance-performance",
6:"normal",
8:"balance-power",
15:"power",
}.get(self._try_parse_num(s), s)
@command_get("energy_perf_bias")
def _get_energy_perf_bias(self, device, ignore_missing=False):
energy_perf_bias = None
if not self._is_cpu_online(device):
log.debug("%s is not online, skipping" % device)
return None
if self._has_energy_perf_bias:
cpu_id = device.lstrip("cpu")
retcode, lines = self._cmd.execute(["x86_energy_perf_policy", "-c", cpu_id, "-r"])
if retcode == 0:
for line in lines.splitlines():
l = line.split()
if len(l) == 2:
energy_perf_bias = self._energy_perf_policy_to_human(l[1])
break
elif len(l) == 3:
energy_perf_bias = self._energy_perf_policy_to_human_v2(l[2])
break
return energy_perf_bias