replace psutil with simple /proc helper

openpilot/common/linux.py

@@ -0,0 +1,50 @@
+class LinuxSystemStats:
+  def __init__(self) -> None:
+    self._last_cpu_times = self._read_cpu_times()
+
+  @staticmethod
+  def _read_cpu_times() -> dict[int, tuple[int, int]]:
+    cpu_times = {}
+    with open('/proc/stat') as f:
+      for line in f:
+        name, *values = line.split()
+        if not name.startswith('cpu') or not name[3:].isdigit():
+          continue
+
+        times = [int(value) for value in values]
+        idle = sum(times[3:5])
+        total = sum(times[:8])
+        cpu_times[int(name[3:])] = (idle, total)
+    return cpu_times
+
+  def cpu_usage_percent(self) -> list[float]:
+    current_cpu_times = self._read_cpu_times()
+    usage = []
+    for cpu, (idle, total) in sorted(current_cpu_times.items()):
+      last_times = self._last_cpu_times.get(cpu)
+      if last_times is None:
+        usage.append(0.)
+        continue
+
+      last_idle, last_total = last_times
+      idle_delta = idle - last_idle
+      total_delta = total - last_total
+      if idle_delta < 0 or total_delta <= 0:
+        usage.append(0.)
+      else:
+        usage.append(max(0., min(100., 100. * (total_delta - idle_delta) / total_delta)))
+
+    self._last_cpu_times = current_cpu_times
+    return usage
+
+  @staticmethod
+  def memory_usage_percent() -> float:
+    memory = {}
+    with open('/proc/meminfo') as f:
+      for line in f:
+        key, value, *_ = line.split()
+        if key in ('MemTotal:', 'MemAvailable:'):
+          memory[key] = int(value)
+
+    total = memory['MemTotal:']
+    return max(0., min(100., 100. * (total - memory['MemAvailable:']) / total))

openpilot/system/hardware/hardwared.py

@@ -7,8 +7,6 @@
 import time
 from collections import OrderedDict, namedtuple
 
-import psutil
-
 import openpilot.cereal.messaging as messaging
 from openpilot.cereal import log
 from openpilot.cereal.services import SERVICE_LIST
@@ -19,6 +17,7 @@
 from openpilot.selfdrive.selfdrived.alertmanager import set_offroad_alert
 from openpilot.common.hardware import HARDWARE, TICI, PC
 from openpilot.common.hardware.usb import get_usb_state, set_usb_state
+from openpilot.common.linux import LinuxSystemStats
 from openpilot.system.loggerd.config import get_available_percent
 from openpilot.common.swaglog import cloudlog
 from openpilot.system.hardware.power_monitoring import PowerMonitoring
@@ -142,6 +141,7 @@ def hw_state_thread(end_event, hw_queue):
 
 
 def hardware_thread(end_event, hw_queue) -> None:
+  system_stats = LinuxSystemStats()
   pm = messaging.PubMaster(['deviceState'])
   sm = messaging.SubMaster(["peripheralState", "gpsLocationExternal", "selfdriveState", "pandaStates"], poll="pandaStates")
 
@@ -232,9 +232,9 @@ def hardware_thread(end_event, hw_queue) -> None:
       pass
 
     msg.deviceState.freeSpacePercent = get_available_percent(default=100.0)
-    msg.deviceState.memoryUsagePercent = int(round(psutil.virtual_memory().percent))
+    msg.deviceState.memoryUsagePercent = int(round(system_stats.memory_usage_percent()))
     msg.deviceState.gpuUsagePercent = int(round(HARDWARE.get_gpu_usage_percent()))
-    online_cpu_usage = [int(round(n)) for n in psutil.cpu_percent(percpu=True)]
+    online_cpu_usage = [int(round(n)) for n in system_stats.cpu_usage_percent()]
     offline_cpu_usage = [0., ] * (len(msg.deviceState.cpuTempC) - len(online_cpu_usage))
     msg.deviceState.cpuUsagePercent = online_cpu_usage + offline_cpu_usage
 

openpilot/system/updated/updated.py

@@ -3,7 +3,6 @@
 import re
 import datetime
 import subprocess
-import psutil
 import shutil
 import signal
 import fcntl
@@ -427,11 +426,6 @@ def main() -> None:
     except OSError as e:
       raise RuntimeError("couldn't get overlay lock; is another instance running?") from e
 
-    # Set low io priority
-    proc = psutil.Process()
-    if psutil.LINUX:
-      proc.ionice(psutil.IOPRIO_CLASS_BE, value=7)
-
     # Check if we just performed an update
     if Path(os.path.join(STAGING_ROOT, "old_openpilot")).is_dir():
       cloudlog.event("update installed")

pyproject.toml

@@ -54,7 +54,6 @@ dependencies = [
   "inputs",
 
   # these should be removed
-  "psutil",
   "setproctitle",
 
   # logreader