openpilot/common/realtime.py

86 lines
2.1 KiB
Python

"""Utilities for reading real time clocks and keeping soft real time constraints."""
import gc
import os
import time
import multiprocessing
from common.clock import sec_since_boot # pylint: disable=no-name-in-module, import-error
from selfdrive.hardware import PC, TICI
# time step for each process
DT_CTRL = 0.01 # controlsd
DT_MDL = 0.05 # model
DT_TRML = 0.5 # thermald and manager
# driver monitoring
if TICI:
DT_DMON = 0.05
else:
DT_DMON = 0.1
class Priority:
# CORE 2
# - modeld = 55
# - camerad = 54
CTRL_LOW = 51 # plannerd & radard
# CORE 3
# - boardd = 55
CTRL_HIGH = 53
def set_realtime_priority(level):
if not PC:
os.sched_setscheduler(0, os.SCHED_FIFO, os.sched_param(level))
def set_core_affinity(core):
if not PC:
os.sched_setaffinity(0, [core,])
def config_realtime_process(core, priority):
gc.disable()
set_realtime_priority(priority)
set_core_affinity(core)
class Ratekeeper():
def __init__(self, rate, print_delay_threshold=0.):
"""Rate in Hz for ratekeeping. print_delay_threshold must be nonnegative."""
self._interval = 1. / rate
self._next_frame_time = sec_since_boot() + self._interval
self._print_delay_threshold = print_delay_threshold
self._frame = 0
self._remaining = 0
self._process_name = multiprocessing.current_process().name
@property
def frame(self):
return self._frame
@property
def remaining(self):
return self._remaining
# Maintain loop rate by calling this at the end of each loop
def keep_time(self):
lagged = self.monitor_time()
if self._remaining > 0:
time.sleep(self._remaining)
return lagged
# this only monitor the cumulative lag, but does not enforce a rate
def monitor_time(self):
lagged = False
remaining = self._next_frame_time - sec_since_boot()
self._next_frame_time += self._interval
if self._print_delay_threshold is not None and remaining < -self._print_delay_threshold:
print("%s lagging by %.2f ms" % (self._process_name, -remaining * 1000))
lagged = True
self._frame += 1
self._remaining = remaining
return lagged