From: Aleš Mrázek <ales.mrazek@nic.cz>
Date: Thu, 27 Jun 2024 13:18:45 +0000 (+0200)
Subject: manager: reset the workers policy rules only when necessary
X-Git-Tag: v6.0.8~8^2~1
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5c2990bbef897809e02140cf29326ff7a7fcba3b;p=thirdparty%2Fknot-resolver.git

manager: reset the workers policy rules only when necessary

Basically, the reset is necessary when only the policy rules have changed and there is no need to update the workers config.
---

diff --git a/manager/knot_resolver_manager/kres_manager.py b/manager/knot_resolver_manager/kres_manager.py
index 3d1a31198..ab8c07022 100644
--- a/manager/knot_resolver_manager/kres_manager.py
+++ b/manager/knot_resolver_manager/kres_manager.py
@@ -19,6 +19,10 @@ from knot_resolver_manager.kresd_controller.interface import (
     SubprocessStatus,
     SubprocessType,
 )
+from knot_resolver_manager.kresd_controller.registered_workers import (
+    command_registered_workers,
+    get_registered_workers_kresids,
+)
 from knot_resolver_manager.utils.functional import Result
 from knot_resolver_manager.utils.modeling.types import NoneType
 
@@ -79,6 +83,7 @@ class KresManager:  # pylint: disable=too-many-instance-attributes
         self._gc: Optional[Subprocess] = None
         self._policy_loader: Optional[Subprocess] = None
         self._manager_lock = asyncio.Lock()
+        self._workers_reset_needed: bool = False
         self._controller: SubprocessController
         self._watchdog_task: Optional["asyncio.Task[None]"] = None
         self._fix_counter: _FixCounter = _FixCounter()
@@ -138,6 +143,9 @@ class KresManager:  # pylint: disable=too-many-instance-attributes
         # register and immediately call a callback to apply config to all 'kresd' workers and 'cache-gc'
         await config_store.register_on_change_callback(only_on_real_changes_update(config_nodes)(self.apply_config))
 
+        # register callback to reset policy rules for each 'kresd' worker
+        await config_store.register_on_change_callback(self.reset_workers_policy_rules)
+
         # register controller config change listeners
         await config_store.register_verifier(_deny_max_worker_changes)
 
@@ -228,6 +236,22 @@ class KresManager:  # pylint: disable=too-many-instance-attributes
             self._gc = None
             await self._collect_already_running_workers()
 
+    async def reset_workers_policy_rules(self, _config: KresConfig) -> None:
+
+        # command all running 'kresd' workers to reset their old policy rules,
+        # unless the workers have already been started with a new config so reset is not needed
+        if self._workers_reset_needed and get_registered_workers_kresids():
+            logger.debug("Resetting policy rules for all running 'kresd' workers")
+            cmd_results = await command_registered_workers("require('ffi').C.kr_rules_reset()")
+            for worker, res in cmd_results.items():
+                if res != 0:
+                    logger.error("Failed to reset policy rules in %s: %s", worker, res)
+        else:
+            logger.debug(
+                "Skipped resetting policy rules for all running 'kresd' workers:"
+                " the workers are already running with new configuration"
+            )
+
     async def apply_config(self, config: KresConfig, _noretry: bool = False) -> None:
         try:
             async with self._manager_lock:
@@ -256,6 +280,8 @@ class KresManager:  # pylint: disable=too-many-instance-attributes
                 await self._reload_system_state()
                 await self.apply_config(config, _noretry=True)
 
+        self._workers_reset_needed = False
+
     async def load_policy_rules(self, _old: KresConfig, new: KresConfig) -> Result[NoneType, str]:
         try:
             async with self._manager_lock:
@@ -271,6 +297,7 @@ class KresManager:  # pylint: disable=too-many-instance-attributes
             logger.error(f"Failed to load policy rules: {e}")
             return Result.err("kresd 'policy-loader' process failed to start. Config might be invalid.")
 
+        self._workers_reset_needed = True
         logger.debug("Loading policy rules has been successfully completed")
         return Result.ok(None)