Dispatch IO thread work to the main dispatch_queue for darwin (#6412)

Author: vivien-apple

src/inet/IPEndPointBasis.cpp

@@ -1082,7 +1082,11 @@ void IPEndPointBasis::HandlePendingIO(uint16_t aPort)
 {
     INET_ERROR lStatus = INET_NO_ERROR;
     IPPacketInfo lPacketInfo;
+#if CHIP_SYSTEM_CONFIG_USE_DISPATCH
+    __block System::PacketBufferHandle lBuffer;
+#else
     System::PacketBufferHandle lBuffer;
+#endif // CHIP_SYSTEM_CONFIG_USE_DISPATCH
 
     lPacketInfo.Clear();
     lPacketInfo.DestPort = aPort;
@@ -1189,12 +1193,35 @@ void IPEndPointBasis::HandlePendingIO(uint16_t aPort)
     if (lStatus == INET_NO_ERROR)
     {
         lBuffer.RightSize();
-        OnMessageReceived(this, std::move(lBuffer), &lPacketInfo);
+
+#if CHIP_SYSTEM_CONFIG_USE_DISPATCH
+        dispatch_queue_t dispatchQueue = SystemLayer().GetDispatchQueue();
+        if (dispatchQueue != nullptr)
+        {
+            dispatch_sync(dispatchQueue, ^{
+                OnMessageReceived(this, std::move(lBuffer), &lPacketInfo);
+            });
+        }
+        else
+#endif // CHIP_SYSTEM_CONFIG_USE_DISPATCH
+            OnMessageReceived(this, std::move(lBuffer), &lPacketInfo);
     }
     else
     {
         if (OnReceiveError != nullptr && lStatus != chip::System::MapErrorPOSIX(EAGAIN))
-            OnReceiveError(this, lStatus, nullptr);
+        {
+#if CHIP_SYSTEM_CONFIG_USE_DISPATCH
+            dispatch_queue_t dispatchQueue = SystemLayer().GetDispatchQueue();
+            if (dispatchQueue != nullptr)
+            {
+                dispatch_sync(dispatchQueue, ^{
+                    OnReceiveError(this, lStatus, nullptr);
+                });
+            }
+            else
+#endif // CHIP_SYSTEM_CONFIG_USE_DISPATCH
+                OnReceiveError(this, lStatus, nullptr);
+        }
     }
 }
 #endif // CHIP_SYSTEM_CONFIG_USE_SOCKETS

src/platform/Darwin/PlatformManagerImpl.cpp

@@ -45,6 +45,8 @@ CHIP_ERROR PlatformManagerImpl::_InitChipStack(void)
     err = Internal::GenericPlatformManagerImpl_POSIX<PlatformManagerImpl>::_InitChipStack();
     SuccessOrExit(err);
 
+    SystemLayer.SetDispatchQueue(GetWorkQueue());
+
 exit:
     return err;
 }

src/system/BUILD.gn

@@ -56,6 +56,7 @@ buildconfig_header("system_buildconfig") {
     "CONFIG_DEVICE_LAYER=${config_device_layer}",
     "CHIP_SYSTEM_CONFIG_TEST=${chip_build_tests}",
     "CHIP_WITH_NLFAULTINJECTION=${chip_with_nlfaultinjection}",
+    "CHIP_SYSTEM_CONFIG_USE_DISPATCH=${chip_system_config_use_dispatch}",
     "CHIP_SYSTEM_CONFIG_USE_LWIP=${chip_system_config_use_lwip}",
     "CHIP_SYSTEM_CONFIG_USE_SOCKETS=${chip_system_config_use_sockets}",
     "CHIP_SYSTEM_CONFIG_USE_NETWORK_FRAMEWORK=false",

src/system/SystemLayer.cpp

@@ -574,7 +574,17 @@ void Layer::DispatchTimerCallbacks(const uint64_t kCurrentEpoch)
         // one-shot
         chip::Callback::Callback<> * cb = chip::Callback::Callback<>::FromCancelable(ready.mNext);
         cb->Cancel();
-        cb->mCall(cb->mContext);
+
+#if CHIP_SYSTEM_CONFIG_USE_DISPATCH
+        if (mDispatchQueue != nullptr)
+        {
+            dispatch_sync(mDispatchQueue, ^{
+                cb->mCall(cb->mContext);
+            });
+        }
+        else
+#endif
+            cb->mCall(cb->mContext);
     }
 }
 
@@ -695,7 +705,16 @@ void Layer::HandleSelectResult(int aSetSize, fd_set * aReadSet, fd_set * aWriteS
 
         if (lTimer != nullptr && !Timer::IsEarlierEpoch(kCurrentEpoch, lTimer->mAwakenEpoch))
         {
-            lTimer->HandleComplete();
+#if CHIP_SYSTEM_CONFIG_USE_DISPATCH
+            if (mDispatchQueue != nullptr)
+            {
+                dispatch_sync(mDispatchQueue, ^{
+                    lTimer->HandleComplete();
+                });
+            }
+            else
+#endif // CHIP_SYSTEM_CONFIG_USE_DISPATCH
+                lTimer->HandleComplete();
         }
     }
 

src/system/SystemLayer.h

@@ -46,6 +46,10 @@
 #include <pthread.h>
 #endif // CHIP_SYSTEM_CONFIG_POSIX_LOCKING
 
+#if CHIP_SYSTEM_CONFIG_USE_DISPATCH
+#include <dispatch/dispatch.h>
+#endif // CHIP_SYSTEM_CONFIG_USE_DISPATCH
+
 namespace chip {
 namespace System {
 
@@ -167,6 +171,11 @@ class DLL_EXPORT Layer
     Error HandlePlatformTimer(void);
 #endif // CHIP_SYSTEM_CONFIG_USE_LWIP
 
+#if CHIP_SYSTEM_CONFIG_USE_DISPATCH
+    void SetDispatchQueue(dispatch_queue_t dispatchQueue) { mDispatchQueue = dispatchQueue; };
+    dispatch_queue_t GetDispatchQueue() { return mDispatchQueue; };
+#endif // CHIP_SYSTEM_CONFIG_USE_DISPATCH
+
     static uint64_t GetClock_Monotonic();
     static uint64_t GetClock_MonotonicMS();
     static uint64_t GetClock_MonotonicHiRes();
@@ -207,6 +216,10 @@ class DLL_EXPORT Layer
     friend Error Platform::Layer::StartTimer(Layer & aLayer, void * aContext, uint32_t aMilliseconds);
 #endif // CHIP_SYSTEM_CONFIG_USE_LWIP
 
+#if CHIP_SYSTEM_CONFIG_USE_DISPATCH
+    dispatch_queue_t mDispatchQueue;
+#endif
+
     // Copy and assignment NOT DEFINED
     Layer(const Layer &) = delete;
     Layer & operator=(const Layer &) = delete;

src/system/system.gni

@@ -33,6 +33,12 @@ declare_args() {
   chip_system_config_provide_statistics = true
 }
 
+declare_args() {
+  # use the dispatch library
+  chip_system_config_use_dispatch = chip_system_config_use_sockets &&
+                                    (current_os == "mac" || current_os == "ios")
+}
+
 if (chip_system_config_locking == "") {
   if (current_os != "freertos") {
     chip_system_config_locking = "posix"