bitbake: cooker: read file watches on server idle

The inotify facility monitoring changes to the config files
could be overwhelmed by massive changes to the watched files
while server is running.

This patch adds verification the notification watches to the
server idle functions, in addition to the cooker updateCache
command which executes only infrequently, thus preventing
overflowing the notification buffer.

[YOCTO #7316]

(Bitbake rev: 996e663fd5c254292f44eca46f5fdc95af897f98)

(Bitbake rev: b44694b1efc7389536df2f901a8b70321edfeeba)

Signed-off-by: Alexandru DAMIAN <alexandru.damian@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/cooker.py

@@ -133,6 +133,19 @@ class BBCooker:
 
 
         self.initConfigurationData()
+
+        self.inotify_modified_files = []
+
+        def _process_inotify_updates(server, notifier_list, abort):
+            for n in notifier_list:
+                if n.check_events(timeout=0):
+                    # read notified events and enqeue them
+                    n.read_events()
+                    n.process_events()
+            return True
+
+        self.configuration.server_register_idlecallback(_process_inotify_updates, [self.confignotifier, self.notifier])
+
         self.baseconfig_valid = True
         self.parsecache_valid = False
 
@@ -171,11 +184,13 @@ class BBCooker:
         signal.signal(signal.SIGHUP, self.sigterm_exception)
 
     def config_notifications(self, event):
-        bb.parse.update_cache(event.path)
+        if not event.path in self.inotify_modified_files:
+            self.inotify_modified_files.append(event.path)
         self.baseconfig_valid = False
 
     def notifications(self, event):
-        bb.parse.update_cache(event.path)
+        if not event.path in self.inotify_modified_files:
+            self.inotify_modified_files.append(event.path)
         self.parsecache_valid = False
 
     def add_filewatch(self, deps, watcher=None):
@@ -1336,11 +1351,12 @@ class BBCooker:
             raise bb.BBHandledException()
 
         if self.state != state.parsing:
-            for n in [self.confignotifier, self.notifier]:
+
-                if n.check_events(timeout=0):
+            # reload files for which we got notifications
-                    # read notified events and enqeue them
+            for p in self.inotify_modified_files:
-                    n.read_events()
+                bb.parse.update_cache(p)
-                n.process_events()
+            self.inotify_modified_files = []
+
             if not self.baseconfig_valid:
                 logger.debug(1, "Reloading base configuration data")
                 self.initConfigurationData()