Buffer async CallInvoker work with module calls (#58313)

Summary:
Pull Request resolved: #58313

In bridgeless, native reaches JS by two routes that end in the same
`RuntimeScheduler` queue but get there differently. `callFunctionOnModule` goes
through the instance's `BufferedRuntimeExecutor`; the `CallInvoker` goes
straight to `scheduleTask`. The CallInvoker therefore skips the buffer entirely
and can reach the runtime while a module call issued earlier is still parked,
unflushed, because the bundle is mid-evaluation. Native code that issues both
cannot rely on the order it issued them in, and `Task` is a min-heap on
`now() + timeout(priority)` with no insertion tiebreak, so equal priorities do
not settle it either.

Gives the two channels the same buffering. `BufferedRuntimeExecutor` gains a
priority-carrying `execute`, so work routed through it keeps the scheduler
priority it was submitted with instead of collapsing to the executor default,
and buffered work from both overloads stays in one submission-ordered stream.
`BufferedCallInvoker` sits on that executor and becomes the bridgeless
`jsCallInvoker` on Android, iOS and macOS.

`invokeSync` deliberately keeps going straight to the scheduler: a synchronous
call cannot wait for a flush that only happens once the bundle has run.

Behind `enableBufferedCallInvoker`, default true. `ReactInstance` picks between
the buffered invoker and the existing `RuntimeSchedulerCallInvoker` in one
place, so the platform call sites are identical either way and the change is
revertible at runtime — it moves when native-issued async work first reaches JS
during startup, which is the intended contract but affects every native module.

One lifetime hazard this surfaces, worth knowing about beyond this diff:
`BufferedRuntimeExecutor` reaches the scheduler through a raw pointer captured
at construction, which is safe only while the owning instance is alive. A
CallInvoker is routinely held across instance teardown, so `BufferedCallInvoker`
guards every async dispatch on a weak reference to the scheduler and drops the
work when it has expired — the same contract `RuntimeSchedulerCallInvoker` has.
Without that guard this reliably segfaults on a reload.

Changelog:
[General][Changed] - Async `CallInvoker` work is now buffered alongside callable module calls, so it no longer runs before the JS bundle has finished evaluating

Reviewed By: rubennorte

Differential Revision: D118456662

Author: javache

packages/react-native/Libraries/AppDelegate/RCTRootViewFactory.mm

@@ -27,7 +27,6 @@
 #import <ReactCommon/RCTHost.h>
 #import <ReactCommon/RCTTurboModuleManager.h>
 #import <react/renderer/runtimescheduler/RuntimeScheduler.h>
-#import <react/renderer/runtimescheduler/RuntimeSchedulerCallInvoker.h>
 #import <react/runtime/JSRuntimeFactory.h>
 #import <react/runtime/JSRuntimeFactoryCAPI.h>
 

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlags.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<ffaf7abad8f9b217cc16e28ee9270b40>>
+ * @generated SignedSource<<b7ef80c2c39c734ae511fe6457b89ce7>>
  */
 
 /**
@@ -114,6 +114,12 @@ public object ReactNativeFeatureFlags {
   @JvmStatic
   public fun enableBridgelessArchitecture(): Boolean = accessor.enableBridgelessArchitecture()
 
+  /**
+   * Route async CallInvoker work through the ReactInstance buffered runtime executor, so it is ordered against callable module calls and cannot run before the JS bundle has finished evaluating. invokeSync is unaffected.
+   */
+  @JvmStatic
+  public fun enableBufferedCallInvoker(): Boolean = accessor.enableBufferedCallInvoker()
+
   /**
    * Enable prop iterator setter-style construction of Props in C++ (this flag is not used in Java).
    */

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsCxxAccessor.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<0bfeba3d07af6fade47b24974a80a592>>
+ * @generated SignedSource<<68aefd0293540d56f57e8badc0de04c8>>
  */
 
 /**
@@ -34,6 +34,7 @@ internal class ReactNativeFeatureFlagsCxxAccessor : ReactNativeFeatureFlagsAcces
   private var enableAccumulatedUpdatesInRawPropsAndroidCache: Boolean? = null
   private var enableAndroidTextMeasurementOptimizationsCache: Boolean? = null
   private var enableBridgelessArchitectureCache: Boolean? = null
+  private var enableBufferedCallInvokerCache: Boolean? = null
   private var enableCppPropsIteratorSetterCache: Boolean? = null
   private var enableCustomFocusSearchOnClippedElementsAndroidCache: Boolean? = null
   private var enableDestroyShadowTreeRevisionAsyncCache: Boolean? = null
@@ -232,6 +233,15 @@ internal class ReactNativeFeatureFlagsCxxAccessor : ReactNativeFeatureFlagsAcces
     return cached
   }
 
+  override fun enableBufferedCallInvoker(): Boolean {
+    var cached = enableBufferedCallInvokerCache
+    if (cached == null) {
+      cached = ReactNativeFeatureFlagsCxxInterop.enableBufferedCallInvoker()
+      enableBufferedCallInvokerCache = cached
+    }
+    return cached
+  }
+
   override fun enableCppPropsIteratorSetter(): Boolean {
     var cached = enableCppPropsIteratorSetterCache
     if (cached == null) {

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsCxxInterop.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<b79fbf8335bf2b480743c3cd93d4e6bd>>
+ * @generated SignedSource<<247f721796621af8615014477518bcd9>>
  */
 
 /**
@@ -56,6 +56,8 @@ public object ReactNativeFeatureFlagsCxxInterop {
 
   @DoNotStrip @JvmStatic public external fun enableBridgelessArchitecture(): Boolean
 
+  @DoNotStrip @JvmStatic public external fun enableBufferedCallInvoker(): Boolean
+
   @DoNotStrip @JvmStatic public external fun enableCppPropsIteratorSetter(): Boolean
 
   @DoNotStrip @JvmStatic public external fun enableCustomFocusSearchOnClippedElementsAndroid(): Boolean

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsDefaults.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<bc2a060e5718ae7afd6d22199c8e9d38>>
+ * @generated SignedSource<<33071257f9c96a8664c9af429e387061>>
  */
 
 /**
@@ -51,6 +51,8 @@ public open class ReactNativeFeatureFlagsDefaults : ReactNativeFeatureFlagsProvi
 
   override fun enableBridgelessArchitecture(): Boolean = true
 
+  override fun enableBufferedCallInvoker(): Boolean = true
+
   override fun enableCppPropsIteratorSetter(): Boolean = false
 
   override fun enableCustomFocusSearchOnClippedElementsAndroid(): Boolean = true

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsLocalAccessor.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<3605df96fad767e3ec3957d7305ef926>>
+ * @generated SignedSource<<f218220c66b8367211cae49adba46afc>>
  */
 
 /**
@@ -38,6 +38,7 @@ internal class ReactNativeFeatureFlagsLocalAccessor : ReactNativeFeatureFlagsAcc
   private var enableAccumulatedUpdatesInRawPropsAndroidCache: Boolean? = null
   private var enableAndroidTextMeasurementOptimizationsCache: Boolean? = null
   private var enableBridgelessArchitectureCache: Boolean? = null
+  private var enableBufferedCallInvokerCache: Boolean? = null
   private var enableCppPropsIteratorSetterCache: Boolean? = null
   private var enableCustomFocusSearchOnClippedElementsAndroidCache: Boolean? = null
   private var enableDestroyShadowTreeRevisionAsyncCache: Boolean? = null
@@ -250,6 +251,16 @@ internal class ReactNativeFeatureFlagsLocalAccessor : ReactNativeFeatureFlagsAcc
     return cached
   }
 
+  override fun enableBufferedCallInvoker(): Boolean {
+    var cached = enableBufferedCallInvokerCache
+    if (cached == null) {
+      cached = currentProvider.enableBufferedCallInvoker()
+      accessedFeatureFlags.add("enableBufferedCallInvoker")
+      enableBufferedCallInvokerCache = cached
+    }
+    return cached
+  }
+
   override fun enableCppPropsIteratorSetter(): Boolean {
     var cached = enableCppPropsIteratorSetterCache
     if (cached == null) {

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsProvider.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<100e31bd98a30aba4abef10f168638fc>>
+ * @generated SignedSource<<915bf918212b9898319de61d4cadaa13>>
  */
 
 /**
@@ -51,6 +51,8 @@ public interface ReactNativeFeatureFlagsProvider {
 
   @DoNotStrip public fun enableBridgelessArchitecture(): Boolean
 
+  @DoNotStrip public fun enableBufferedCallInvoker(): Boolean
+
   @DoNotStrip public fun enableCppPropsIteratorSetter(): Boolean
 
   @DoNotStrip public fun enableCustomFocusSearchOnClippedElementsAndroid(): Boolean

packages/react-native/ReactAndroid/src/main/jni/react/featureflags/JReactNativeFeatureFlagsCxxInterop.cpp

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<ce8ba846a2e567547c4ba7370b9f4e89>>
+ * @generated SignedSource<<177c5cc7f6e970a2d4454c32d7f777ef>>
  */
 
 /**
@@ -123,6 +123,12 @@ class ReactNativeFeatureFlagsJavaProvider
     return method(javaProvider_);
   }
 
+  bool enableBufferedCallInvoker() override {
+    static const auto method =
+        getReactNativeFeatureFlagsProviderJavaClass()->getMethod<jboolean()>("enableBufferedCallInvoker");
+    return method(javaProvider_);
+  }
+
   bool enableCppPropsIteratorSetter() override {
     static const auto method =
         getReactNativeFeatureFlagsProviderJavaClass()->getMethod<jboolean()>("enableCppPropsIteratorSetter");
@@ -623,6 +629,11 @@ bool JReactNativeFeatureFlagsCxxInterop::enableBridgelessArchitecture(
   return ReactNativeFeatureFlags::enableBridgelessArchitecture();
 }
 
+bool JReactNativeFeatureFlagsCxxInterop::enableBufferedCallInvoker(
+    facebook::jni::alias_ref<JReactNativeFeatureFlagsCxxInterop> /*unused*/) {
+  return ReactNativeFeatureFlags::enableBufferedCallInvoker();
+}
+
 bool JReactNativeFeatureFlagsCxxInterop::enableCppPropsIteratorSetter(
     facebook::jni::alias_ref<JReactNativeFeatureFlagsCxxInterop> /*unused*/) {
   return ReactNativeFeatureFlags::enableCppPropsIteratorSetter();
@@ -1051,6 +1062,9 @@ void JReactNativeFeatureFlagsCxxInterop::registerNatives() {
       makeNativeMethod(
         "enableBridgelessArchitecture",
         JReactNativeFeatureFlagsCxxInterop::enableBridgelessArchitecture),
+      makeNativeMethod(
+        "enableBufferedCallInvoker",
+        JReactNativeFeatureFlagsCxxInterop::enableBufferedCallInvoker),
       makeNativeMethod(
         "enableCppPropsIteratorSetter",
         JReactNativeFeatureFlagsCxxInterop::enableCppPropsIteratorSetter),

packages/react-native/ReactAndroid/src/main/jni/react/featureflags/JReactNativeFeatureFlagsCxxInterop.h

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<145b12c4a208db86c7bfdfed56cf433f>>
+ * @generated SignedSource<<eab10e240a16c8ef3f659bd8ded290f0>>
  */
 
 /**
@@ -72,6 +72,9 @@ class JReactNativeFeatureFlagsCxxInterop
   static bool enableBridgelessArchitecture(
     facebook::jni::alias_ref<JReactNativeFeatureFlagsCxxInterop>);
 
+  static bool enableBufferedCallInvoker(
+    facebook::jni::alias_ref<JReactNativeFeatureFlagsCxxInterop>);
+
   static bool enableCppPropsIteratorSetter(
     facebook::jni::alias_ref<JReactNativeFeatureFlagsCxxInterop>);
 

packages/react-native/ReactAndroid/src/main/jni/react/runtime/jni/JReactInstance.cpp

@@ -15,7 +15,6 @@
 #include <jsi/jsi.h>
 #include <react/jni/JRuntimeExecutor.h>
 #include <react/jni/JSLogging.h>
-#include <react/renderer/runtimescheduler/RuntimeSchedulerCallInvoker.h>
 #include <react/runtime/BridgelessNativeMethodCallInvoker.h>
 #include <react/runtime/JSRuntimeBindings.h>
 
@@ -89,10 +88,11 @@ JReactInstance::JReactInstance(
 
   auto unbufferedRuntimeExecutor = instance_->getUnbufferedRuntimeExecutor();
   // Set up the JS and native modules call invokers (for TurboModules)
-  auto jsInvoker = std::make_unique<RuntimeSchedulerCallInvoker>(
-      instance_->getRuntimeScheduler());
+  // Shares the instance's BufferedRuntimeExecutor so async calls from native
+  // are ordered against callFunctionOnModule and cannot run before the bundle
+  // has evaluated. invokeSync still goes straight to the scheduler.
   jsCallInvokerHolder_ = jni::make_global(
-      CallInvokerHolder::newObjectCxxArgs(std::move(jsInvoker)));
+      CallInvokerHolder::newObjectCxxArgs(instance_->createJSCallInvoker()));
   auto nativeMethodCallInvoker =
       std::make_unique<BridgelessNativeMethodCallInvoker>(
           sharedNativeMessageQueueThread);