[Darwin] MTRDevice delegate callbacks should call out without holding lock (#37668)

* [Darwin] MTRDevice delegate callbacks should call out without holding lock

* Fixed compilation issues

* Update src/darwin/Framework/CHIP/MTRDevice_XPC.mm

Co-authored-by: Boris Zbarsky <bzbarsky@apple.com>

* Update src/darwin/Framework/CHIP/MTRDevice_XPC.mm

Co-authored-by: Boris Zbarsky <bzbarsky@apple.com>

* Change back to lock_guard

---------

Co-authored-by: Boris Zbarsky <bzbarsky@apple.com>

Author: jtung-apple

src/darwin/Framework/CHIP/MTRDeviceController_XPC.mm

@@ -23,6 +23,7 @@
 #import "MTRDevice_XPC_Internal.h"
 #import "MTRError_Internal.h"
 #import "MTRLogging_Internal.h"
+#import "MTRUnfairLock.h"
 #import "MTRXPCClientProtocol.h"
 #import "MTRXPCServerProtocol.h"
 
@@ -72,28 +73,26 @@ @implementation MTRDeviceController_XPC
 
 - (void)_updateRegistrationInfo
 {
-    dispatch_async(self.workQueue, ^{
-        std::lock_guard lock(*self.deviceMapLock);
+    std::lock_guard lock(*self.deviceMapLock);
 
-        NSMutableDictionary * registrationInfo = [NSMutableDictionary dictionary];
+    NSMutableDictionary * registrationInfo = [NSMutableDictionary dictionary];
 
-        NSMutableDictionary * controllerContext = [NSMutableDictionary dictionary];
-        NSMutableArray * nodeIDs = [NSMutableArray array];
+    NSMutableDictionary * controllerContext = [NSMutableDictionary dictionary];
+    NSMutableArray * nodeIDs = [NSMutableArray array];
 
-        for (NSNumber * nodeID in [self.nodeIDToDeviceMap keyEnumerator]) {
-            MTRDevice * device = self.nodeIDToDeviceMap[nodeID];
-            if ([device delegateExists]) {
-                NSMutableDictionary * nodeDictionary = [NSMutableDictionary dictionary];
-                MTR_REQUIRED_ATTRIBUTE(MTRDeviceControllerRegistrationNodeIDKey, nodeID, nodeDictionary)
+    for (NSNumber * nodeID in [self.nodeIDToDeviceMap keyEnumerator]) {
+        MTRDevice * device = [self.nodeIDToDeviceMap objectForKey:nodeID];
+        if ([device delegateExists]) {
+            NSMutableDictionary * nodeDictionary = [NSMutableDictionary dictionary];
+            MTR_REQUIRED_ATTRIBUTE(MTRDeviceControllerRegistrationNodeIDKey, nodeID, nodeDictionary)
 
-                [nodeIDs addObject:nodeDictionary];
-            }
+            [nodeIDs addObject:nodeDictionary];
         }
-        MTR_REQUIRED_ATTRIBUTE(MTRDeviceControllerRegistrationNodeIDsKey, nodeIDs, registrationInfo)
-        MTR_REQUIRED_ATTRIBUTE(MTRDeviceControllerRegistrationControllerContextKey, controllerContext, registrationInfo)
+    }
+    MTR_REQUIRED_ATTRIBUTE(MTRDeviceControllerRegistrationNodeIDsKey, nodeIDs, registrationInfo)
+    MTR_REQUIRED_ATTRIBUTE(MTRDeviceControllerRegistrationControllerContextKey, controllerContext, registrationInfo)
 
-        [self updateControllerConfiguration:registrationInfo];
-    });
+    [self updateControllerConfiguration:registrationInfo];
 }
 
 - (void)_registerNodeID:(NSNumber *)nodeID

src/darwin/Framework/CHIP/MTRDevice_XPC.mm

@@ -151,16 +151,28 @@ - (MTRNetworkCommissioningFeature)networkCommissioningFeatures
 
 - (void)_delegateAdded:(id<MTRDeviceDelegate>)delegate
 {
+    os_unfair_lock_assert_owner(&self->_lock);
+
     [super _delegateAdded:delegate];
     MTR_LOG("%@ delegate added: %@", self, delegate);
-    [(MTRDeviceController_XPC *) [self deviceController] _updateRegistrationInfo];
+
+    // dispatch to own queue so we're not holding our lock while calling out to the controller code.
+    dispatch_async(self.queue, ^{
+        [(MTRDeviceController_XPC *) [self deviceController] _updateRegistrationInfo];
+    });
 }
 
 - (void)_delegateRemoved:(id<MTRDeviceDelegate>)delegate
 {
+    os_unfair_lock_assert_owner(&self->_lock);
+
     [super _delegateRemoved:delegate];
     MTR_LOG("%@ delegate removed: %@", self, delegate);
-    [(MTRDeviceController_XPC *) [self deviceController] _updateRegistrationInfo];
+
+    // dispatch to own queue so we're not holding our lock while calling out to the controller code.
+    dispatch_async(self.queue, ^{
+        [(MTRDeviceController_XPC *) [self deviceController] _updateRegistrationInfo];
+    });
 }
 
 #pragma mark - Client Callbacks (MTRDeviceDelegate)