Support realtime scheduling for add-ons (#2593)

* Support realtime scheduling for add-ons

* support on audio

* address comments from @jens-maus

supervisor/addons/model.py

@@ -45,6 +45,7 @@ from ..const import (
     ATTR_PORTS,
     ATTR_PORTS_DESCRIPTION,
     ATTR_PRIVILEGED,
+    ATTR_REALTIME,
     ATTR_REPOSITORY,
     ATTR_SCHEMA,
     ATTR_SERVICES,
@@ -396,6 +397,11 @@ class AddonModel(CoreSysAttributes, ABC):
         """Return True if the add-on access to kernel modules."""
         return self.data[ATTR_KERNEL_MODULES]
 
+    @property
+    def with_realtime(self) -> bool:
+        """Return True if the add-on need realtime schedule functions."""
+        return self.data[ATTR_REALTIME]
+
     @property
     def with_full_access(self) -> bool:
         """Return True if the add-on want full access to hardware."""

supervisor/addons/validate.py

@@ -59,6 +59,7 @@ from ..const import (
     ATTR_PORTS_DESCRIPTION,
     ATTR_PRIVILEGED,
     ATTR_PROTECTED,
+    ATTR_REALTIME,
     ATTR_REPOSITORY,
     ATTR_SCHEMA,
     ATTR_SERVICES,
@@ -263,6 +264,7 @@ _SCHEMA_ADDON_CONFIG = vol.Schema(
         vol.Optional(ATTR_UART, default=False): vol.Boolean(),
         vol.Optional(ATTR_DEVICETREE, default=False): vol.Boolean(),
         vol.Optional(ATTR_KERNEL_MODULES, default=False): vol.Boolean(),
+        vol.Optional(ATTR_REALTIME, default=False): vol.Boolean(),
         vol.Optional(ATTR_HASSIO_API, default=False): vol.Boolean(),
         vol.Optional(ATTR_HASSIO_ROLE, default=ROLE_DEFAULT): vol.In(ROLE_ALL),
         vol.Optional(ATTR_HOMEASSISTANT_API, default=False): vol.Boolean(),

supervisor/const.py

@@ -289,6 +289,7 @@ ATTR_FREQUENCY = "frequency"
 ATTR_ACCESSPOINTS = "accesspoints"
 ATTR_UNHEALTHY = "unhealthy"
 ATTR_OTA = "ota"
+ATTR_REALTIME = "realtime"
 
 PROVIDE_SERVICE = "provide"
 NEED_SERVICE = "need"

supervisor/docker/addon.py

@@ -250,11 +250,36 @@ class DockerAddon(DockerInterface):
         if self.addon.with_kernel_modules:
             capabilities.add(Capabilities.SYS_MODULE)
 
+        # Need schedule functions
+        if self.addon.with_realtime:
+            capabilities.add(Capabilities.SYS_NICE)
+
         # Return None if no capabilities is present
         if capabilities:
             return [cap.value for cap in capabilities]
         return None
 
+    @property
+    def ulimits(self) -> Optional[List[docker.types.Ulimit]]:
+        """Generate ulimits for add-on."""
+        limits: List[docker.types.Ulimit] = []
+
+        # Need schedule functions
+        if self.addon.with_realtime:
+            limits.append(docker.types.Ulimit(name="rtprio", soft=99))
+
+        # Return None if no capabilities is present
+        if limits:
+            return limits
+        return None
+
+    @property
+    def cpu_rt_runtime(self) -> Optional[int]:
+        """Limit CPU real-time runtime in microseconds."""
+        if self.addon.with_realtime:
+            return 950000
+        return None
+
     @property
     def volumes(self) -> Dict[str, Dict[str, str]]:
         """Generate volumes for mappings."""
@@ -416,6 +441,8 @@ class DockerAddon(DockerInterface):
                 extra_hosts=self.network_mapping,
                 device_cgroup_rules=self.cgroups_rules,
                 cap_add=self.capabilities,
+                ulimits=self.ulimits,
+                cpu_rt_runtime=self.cpu_rt_runtime,
                 security_opt=self.security_opt,
                 environment=self.environment,
                 volumes=self.volumes,

supervisor/docker/audio.py

@@ -2,6 +2,8 @@
 import logging
 from typing import Dict, List
 
+import docker
+
 from ..const import ENV_TIME, MACHINE_ID
 from ..coresys import CoreSysAttributes
 from ..docker.const import Capabilities
@@ -54,6 +56,11 @@ class DockerAudio(DockerInterface, CoreSysAttributes):
         """Generate needed capabilities."""
         return [cap.value for cap in (Capabilities.SYS_NICE, Capabilities.SYS_RESOURCE)]
 
+    @property
+    def ulimits(self) -> List[docker.types.Ulimit]:
+        """Generate ulimits for audio."""
+        return [docker.types.Ulimit(name="rtprio", soft=99)]
+
     def _run(self) -> None:
         """Run Docker image.
 
@@ -75,6 +82,8 @@ class DockerAudio(DockerInterface, CoreSysAttributes):
             hostname=self.name.replace("_", "-"),
             detach=True,
             cap_add=self.capabilities,
+            ulimits=self.ulimits,
+            cpu_rt_runtime=950000,
             device_cgroup_rules=self.cgroups_rules,
             environment={ENV_TIME: self.sys_config.timezone},
             volumes=self.volumes,