Lua: Change the TLS callback function type of ThreadLocalState to Upd…

source/extensions/filters/common/lua/lua.cc

@@ -71,8 +71,8 @@ int ThreadLocalState::getGlobalRef(uint64_t slot) {
 }
 
 uint64_t ThreadLocalState::registerGlobal(const std::string& global) {
-  tls_slot_->runOnAllThreads([this, global]() {
-    LuaThreadLocal& tls = tls_slot_->getTyped<LuaThreadLocal>();
+  tls_slot_->runOnAllThreads([global](ThreadLocal::ThreadLocalObjectSharedPtr previous) {
+    LuaThreadLocal& tls = *std::dynamic_pointer_cast<LuaThreadLocal>(previous);
     lua_getglobal(tls.state_.get(), global.c_str());
     if (lua_isfunction(tls.state_.get(), -1)) {
       tls.global_slots_.push_back(luaL_ref(tls.state_.get(), LUA_REGISTRYINDEX));
@@ -81,6 +81,7 @@ uint64_t ThreadLocalState::registerGlobal(const std::string& global) {
       lua_pop(tls.state_.get(), 1);
       tls.global_slots_.push_back(LUA_REFNIL);
     }
+    return previous;
   });
 
   return current_global_slot_++;

source/extensions/filters/common/lua/lua.h

@@ -386,8 +386,11 @@ class ThreadLocalState : Logger::Loggable<Logger::Id::lua> {
    * all threaded workers.
    */
   template <class T> void registerType() {
-    tls_slot_->runOnAllThreads(
-        [this]() { T::registerType(tls_slot_->getTyped<LuaThreadLocal>().state_.get()); });
+    tls_slot_->runOnAllThreads([](ThreadLocal::ThreadLocalObjectSharedPtr previous) {
+      LuaThreadLocal& tls = *std::dynamic_pointer_cast<LuaThreadLocal>(previous);
+      T::registerType(tls.state_.get());
+      return previous;
+    });
   }
 
   /**

test/extensions/filters/common/lua/BUILD

@@ -14,6 +14,7 @@ envoy_cc_test(
     srcs = ["lua_test.cc"],
     tags = ["skip_on_windows"],
     deps = [
+        "//source/common/thread_local:thread_local_lib",
         "//source/extensions/filters/common/lua:lua_lib",
         "//test/mocks:common_lib",
         "//test/mocks/thread_local:thread_local_mocks",

test/extensions/filters/common/lua/lua_test.cc

@@ -1,5 +1,7 @@
 #include <memory>
 
+#include "common/thread_local/thread_local_impl.h"
+
 #include "extensions/filters/common/lua/lua.h"
 
 #include "test/mocks/common.h"
@@ -157,6 +159,55 @@ TEST_F(LuaTest, MarkDead) {
   lua_gc(cr1->luaState(), LUA_GCCOLLECT, 0);
 }
 
+class ThreadSafeTest : public testing::Test {
+public:
+  ThreadSafeTest()
+      : api_(Api::createApiForTest()), main_dispatcher_(api_->allocateDispatcher("main")),
+        worker_dispatcher_(api_->allocateDispatcher("worker")) {}
+
+  // Use real dispatchers to verify that callback functions can be executed correctly.
+  Api::ApiPtr api_;
+  Event::DispatcherPtr main_dispatcher_;
+  Event::DispatcherPtr worker_dispatcher_;
+  ThreadLocal::InstanceImpl tls_;
+
+  std::unique_ptr<ThreadLocalState> state_;
+};
+
+// Test whether ThreadLocalState can be safely released.
+TEST_F(ThreadSafeTest, StateDestructedBeforeWorkerRun) {
+  const std::string SCRIPT{R"EOF(
+    function HelloWorld()
+      print("Hello World!")
+    end
+  )EOF"};
+
+  tls_.registerThread(*main_dispatcher_, true);
+  EXPECT_EQ(main_dispatcher_.get(), &tls_.dispatcher());
+  tls_.registerThread(*worker_dispatcher_, false);
+
+  // Some callback functions waiting to be executed will be added to the dispatcher of the Worker
+  // thread. The callback functions in the main thread will be executed directly.
+  state_ = std::make_unique<ThreadLocalState>(SCRIPT, tls_);
+  state_->registerType<TestObject>();
+
+  main_dispatcher_->run(Event::Dispatcher::RunType::Block);
+
+  // Destroy state_.
+  state_.reset(nullptr);
+
+  // Start a new worker thread to execute the callback functions in the worker dispatcher.
+  Thread::ThreadPtr thread = Thread::threadFactoryForTest().createThread([this]() {
+    worker_dispatcher_->run(Event::Dispatcher::RunType::Block);
+    // Verify we have the expected dispatcher for the new worker thread.
+    EXPECT_EQ(worker_dispatcher_.get(), &tls_.dispatcher());
+  });
+  thread->join();
+
+  tls_.shutdownGlobalThreading();
+  tls_.shutdownThread();
+}
+
 } // namespace
 } // namespace Lua
 } // namespace Common