[browser][MT] add memory barriers before sending messages to other workers

src/mono/CMakeLists.txt

@@ -238,6 +238,9 @@ elseif(CLR_CMAKE_HOST_OS STREQUAL "emscripten")
   add_compile_options(-Wno-strict-prototypes)
   add_compile_options(-Wno-unused-but-set-variable)
   add_compile_options(-Wno-single-bit-bitfield-constant-conversion)
+  if(NOT DISABLE_THREADS)
+    add_compile_options(-matomics)
+  endif()
   set(DISABLE_EXECUTABLES 1)
   # FIXME: Is there a cmake option for this ?
   set(DISABLE_SHARED_LIBS 1)

src/mono/browser/browser.proj

@@ -265,9 +265,6 @@
     <ItemGroup Condition="'$(WasmEnableThreads)' == 'true'">
       <EmccExportedFunction Include="_emscripten_main_runtime_thread_id"  />
     </ItemGroup>
-    <ItemGroup Condition="'$(WasmEnableThreads)' == 'true'">
-      <EmccExportedFunction Include="_emscripten_main_runtime_thread_id"  />
-    </ItemGroup>
     <PropertyGroup>
       <_EmccExportedLibraryFunction>"[@(EmccExportedLibraryFunction -> '%27%(Identity)%27', ',')]"</_EmccExportedLibraryFunction>
       <_EmccExportedRuntimeMethods>"[@(EmccExportedRuntimeMethod -> '%27%(Identity)%27', ',')]"</_EmccExportedRuntimeMethods>
@@ -408,6 +405,7 @@
       <CMakeBuildRuntimeConfigureCmd Condition="'$(WasmEnableSIMD)' == 'true'">$(CMakeBuildRuntimeConfigureCmd) -DCONFIGURATION_COMPILE_OPTIONS=&quot;-msimd128&quot; -DCONFIGURATION_INTERPSIMDTABLES_LIB=&quot;simd&quot;</CMakeBuildRuntimeConfigureCmd>
       <CMakeBuildRuntimeConfigureCmd Condition="'$(WasmEnableSIMD)' != 'true'">$(CMakeBuildRuntimeConfigureCmd) -DCONFIGURATION_INTERPSIMDTABLES_LIB=&quot;nosimd&quot;</CMakeBuildRuntimeConfigureCmd>
       <CMakeBuildRuntimeConfigureCmd Condition="'$(WasmEnableThreads)' == 'true'">$(CMakeBuildRuntimeConfigureCmd) -DDISABLE_THREADS=0</CMakeBuildRuntimeConfigureCmd>
+      <CMakeBuildRuntimeConfigureCmd Condition="'$(WasmEnableThreads)' != 'true'">$(CMakeBuildRuntimeConfigureCmd) -DDISABLE_THREADS=1</CMakeBuildRuntimeConfigureCmd>
       <CMakeBuildRuntimeConfigureCmd Condition="'$(WasmEnableJsInteropByValue)' == 'true'">$(CMakeBuildRuntimeConfigureCmd) -DENABLE_JS_INTEROP_BY_VALUE=1</CMakeBuildRuntimeConfigureCmd>
       <CMakeBuildRuntimeConfigureCmd>$(CMakeBuildRuntimeConfigureCmd) $(CMakeConfigurationEmsdkPath)</CMakeBuildRuntimeConfigureCmd>
 

src/mono/browser/runtime/corebindings.c

@@ -38,6 +38,8 @@ void mono_wasm_assembly_get_entry_point (char *assembly_name, int auto_insert_br
 void mono_wasm_get_assembly_export (char *assembly_name, char *namespace, char *classname, char *methodname, int signature_hash, MonoMethod **method_out);
 
 #ifndef DISABLE_THREADS
+void wasm_atomic_fence(void);
+
 void mono_wasm_release_cs_owned_object_post (pthread_t target_tid, int js_handle);
 void mono_wasm_resolve_or_reject_promise_post (pthread_t target_tid, void *args);
 void mono_wasm_cancel_promise_post (pthread_t target_tid, int task_holder_gc_handle);
@@ -46,6 +48,7 @@ extern void mono_wasm_install_js_worker_interop (int context_gc_handle);
 void mono_wasm_install_js_worker_interop_wrapper (int context_gc_handle, void* beforeSyncJSImport, void* afterSyncJSImport, void* pumpHandler);
 extern void mono_wasm_uninstall_js_worker_interop ();
 extern void mono_wasm_invoke_jsimport_MT (void* signature, void* args);
+void mono_wasm_invoke_jsimport_MT_barrier (void* signature, void* args);
 void mono_wasm_invoke_jsimport_async_post (pthread_t target_tid, void* signature, void* args);
 void mono_wasm_invoke_jsimport_sync_send (pthread_t target_tid, void* signature, void* args);
 void mono_wasm_invoke_js_function_send (pthread_t target_tid, int function_js_handle, void *args);
@@ -73,7 +76,7 @@ void bindings_initialize_internals (void)
 	mono_add_internal_call ("Interop/Runtime::ResolveOrRejectPromisePost", mono_wasm_resolve_or_reject_promise_post);
 	mono_add_internal_call ("Interop/Runtime::InstallWebWorkerInterop", mono_wasm_install_js_worker_interop_wrapper);
 	mono_add_internal_call ("Interop/Runtime::UninstallWebWorkerInterop", mono_wasm_uninstall_js_worker_interop);
-	mono_add_internal_call ("Interop/Runtime::InvokeJSImportSync", mono_wasm_invoke_jsimport_MT);
+	mono_add_internal_call ("Interop/Runtime::InvokeJSImportSync", mono_wasm_invoke_jsimport_MT_barrier);
 	mono_add_internal_call ("Interop/Runtime::InvokeJSImportSyncSend", mono_wasm_invoke_jsimport_sync_send);
 	mono_add_internal_call ("Interop/Runtime::InvokeJSImportAsyncPost", mono_wasm_invoke_jsimport_async_post);
 	mono_add_internal_call ("Interop/Runtime::InvokeJSFunctionSend", mono_wasm_invoke_js_function_send);
@@ -255,43 +258,64 @@ void mono_wasm_install_js_worker_interop_wrapper (int context_gc_handle, void* b
 	before_sync_js_import = beforeSyncJSImport;
 	after_sync_js_import = afterSyncJSImport;
 	synchronization_context_pump_handler = pumpHandler;
+	__sync_synchronize ();
+	wasm_atomic_fence ();
 	mono_wasm_install_js_worker_interop (context_gc_handle);
 }
 
 // async
 void mono_wasm_release_cs_owned_object_post (pthread_t target_tid, int js_handle)
 {
+	__sync_synchronize ();
+	wasm_atomic_fence ();
 	mono_threads_wasm_async_run_in_target_thread_vi (target_tid, (void (*) (gpointer))mono_wasm_release_cs_owned_object, (gpointer)js_handle);
 }
 
 // async
 void mono_wasm_resolve_or_reject_promise_post (pthread_t target_tid, void* args)
 {
+	__sync_synchronize ();
+	wasm_atomic_fence ();
 	mono_threads_wasm_async_run_in_target_thread_vi (target_tid, (void (*) (gpointer))mono_wasm_resolve_or_reject_promise, (gpointer)args);
 }
 
 // async
 void mono_wasm_cancel_promise_post (pthread_t target_tid, int task_holder_gc_handle)
 {
+	__sync_synchronize ();
+	wasm_atomic_fence ();
 	mono_threads_wasm_async_run_in_target_thread_vi (target_tid, (void (*) (gpointer))mono_wasm_cancel_promise, (gpointer)task_holder_gc_handle);
 }
 
 // async
 void mono_wasm_invoke_jsimport_async_post (pthread_t target_tid, void* signature, void* args)
 {
-	mono_threads_wasm_async_run_in_target_thread_vii (target_tid, (void (*) (gpointer, gpointer))mono_wasm_invoke_jsimport_MT, (gpointer)signature, (gpointer)args);
+	__sync_synchronize ();
+	wasm_atomic_fence ();
+	mono_threads_wasm_async_run_in_target_thread_vii (target_tid, (void (*) (gpointer, gpointer))mono_wasm_invoke_jsimport_MT_barrier, (gpointer)signature, (gpointer)args);
 }
 
 // sync
 void mono_wasm_invoke_jsimport_sync_send (pthread_t target_tid, void* signature, void* args)
 {
-	mono_threads_wasm_sync_run_in_target_thread_vii (target_tid, (void (*) (gpointer, gpointer))mono_wasm_invoke_jsimport_MT, (gpointer)signature, (gpointer)args);
+	__sync_synchronize ();
+	wasm_atomic_fence ();
+	mono_threads_wasm_sync_run_in_target_thread_vii (target_tid, (void (*) (gpointer, gpointer))mono_wasm_invoke_jsimport_MT_barrier, (gpointer)signature, (gpointer)args);
 }
 
 // sync
 void mono_wasm_invoke_js_function_send (pthread_t target_tid, int function_js_handle, void *args)
 {
+	__sync_synchronize ();
+	wasm_atomic_fence ();
 	mono_threads_wasm_sync_run_in_target_thread_vii (target_tid, (void (*) (gpointer, gpointer))mono_wasm_invoke_js_function, (gpointer)function_js_handle, (gpointer)args);
 }
 
+void mono_wasm_invoke_jsimport_MT_barrier (void* signature, void* args)
+{
+	__sync_synchronize ();
+	wasm_atomic_fence ();
+	mono_wasm_invoke_jsimport_MT (signature, args);
+}
+
 #endif /* DISABLE_THREADS */

src/mono/browser/runtime/driver.c

@@ -46,6 +46,11 @@ char *mono_method_get_full_name (MonoMethod *method);
 #ifndef INVARIANT_TIMEZONE
 extern void mono_register_timezones_bundle (void);
 #endif /* INVARIANT_TIMEZONE */
+
+#ifndef DISABLE_THREADS
+void wasm_atomic_fence(void);
+#endif /* DISABLE_THREADS */
+
 extern void mono_wasm_set_entrypoint_breakpoint (const char* assembly_name, int method_token);
 
 extern void mono_bundled_resources_add_assembly_resource (const char *id, const char *name, const uint8_t *data, uint32_t size, void (*free_func)(void *, void*), void *free_data);
@@ -188,6 +193,11 @@ mono_wasm_load_runtime (int debug_level)
 	runtime_initialized = 1;
 	const char *interp_opts = "";
 
+#ifndef DISABLE_THREADS
+	wasm_atomic_fence ();
+	__sync_synchronize ();
+#endif /* DISABLE_THREADS */
+
 #ifndef INVARIANT_GLOBALIZATION
 	mono_wasm_link_icu_shim ();
 #endif
@@ -230,6 +240,12 @@ mono_wasm_load_runtime (int debug_level)
 	root_domain = mono_wasm_load_runtime_common (debug_level, wasm_trace_logger, interp_opts);
 
 	bindings_initialize_internals();
+
+#ifndef DISABLE_THREADS
+	wasm_atomic_fence ();
+	__sync_synchronize ();
+#endif /* DISABLE_THREADS */
+
 }
 
 int initialize_runtime()
@@ -283,6 +299,8 @@ mono_wasm_print_thread_dump (void)
 static void
 mono_wasm_invoke_jsexport_async_post_cb (MonoMethod *method, void* args)
 {
+	wasm_atomic_fence ();
+	__sync_synchronize ();
 	mono_wasm_invoke_jsexport (method, args);
 	if (args) {
 		MonoBoolean *is_receiver_should_free = (MonoBoolean *)(((char *) args) + 20/*JSMarshalerArgumentOffsets.ReceiverShouldFree*/);
@@ -296,6 +314,8 @@ mono_wasm_invoke_jsexport_async_post_cb (MonoMethod *method, void* args)
 EMSCRIPTEN_KEEPALIVE void
 mono_wasm_invoke_jsexport_async_post (void* target_thread, MonoMethod *method, void* args /*JSMarshalerArguments*/)
 {
+	wasm_atomic_fence ();
+	__sync_synchronize ();
 	mono_threads_wasm_async_run_in_target_thread_vii(target_thread, (void (*)(gpointer, gpointer))mono_wasm_invoke_jsexport_async_post_cb, method, args);
 }
 
@@ -310,6 +330,8 @@ extern sync_context_pump synchronization_context_pump_handler;
 EMSCRIPTEN_KEEPALIVE void
 mono_wasm_invoke_jsexport_sync (MonoMethod *method, void* args)
 {
+	wasm_atomic_fence ();
+	__sync_synchronize ();
 	before_sync_js_import (args);
 	mono_wasm_invoke_jsexport (method, args);
 	after_sync_js_import (args);
@@ -319,6 +341,8 @@ mono_wasm_invoke_jsexport_sync (MonoMethod *method, void* args)
 EMSCRIPTEN_KEEPALIVE void
 mono_wasm_invoke_jsexport_sync_send (void* target_thread, MonoMethod *method, void* args /*JSMarshalerArguments*/)
 {
+	wasm_atomic_fence ();
+	__sync_synchronize ();
 	mono_threads_wasm_sync_run_in_target_thread_vii (target_thread, (void (*)(gpointer, gpointer))mono_wasm_invoke_jsexport_sync, method, args);
 }
 

src/mono/browser/runtime/pthreads/deputy-thread.ts

@@ -39,6 +39,7 @@ export function mono_wasm_start_deputy_thread_async () {
                     }
                 });
 
+                forceThreadMemoryViewRefresh();
                 await start_runtime();
 
                 postMessageToMain({

src/mono/browser/runtime/pthreads/ui-thread.ts

@@ -9,6 +9,7 @@ import { MonoWorkerToMainMessage, monoThreadInfo, mono_wasm_pthread_ptr, update_
 import { Module, ENVIRONMENT_IS_WORKER, createPromiseController, loaderHelpers, mono_assert, runtimeHelpers } from "../globals";
 import { PThreadLibrary, MainToWorkerMessageType, MonoThreadMessage, PThreadInfo, PThreadPtr, PThreadPtrNull, PThreadWorker, PromiseController, Thread, WorkerToMainMessageType, monoMessageSymbol } from "../types/internal";
 import { mono_log_info, mono_log_debug, mono_log_warn } from "../logging";
+import { forceThreadMemoryViewRefresh } from "../memory";
 
 const threadPromises: Map<PThreadPtr, PromiseController<Thread>[]> = new Map();
 
@@ -71,6 +72,8 @@ function monoWorkerMessageHandler (worker: PThreadWorker, ev: MessageEvent<any>)
         return;
     }
 
+    forceThreadMemoryViewRefresh();
+
     let thread: Thread;
     pthreadId = message.info?.pthreadId ?? 0;
     worker.info = Object.assign({}, worker.info, message.info);

src/mono/browser/runtime/startup.ts

@@ -28,7 +28,7 @@ import { populateEmscriptenPool, mono_wasm_init_threads } from "./pthreads";
 import { currentWorkerThreadEvents, dotnetPthreadCreated, initWorkerThreadEvents, monoThreadInfo } from "./pthreads";
 import { mono_wasm_pthread_ptr, update_thread_info } from "./pthreads";
 import { jiterpreter_allocate_tables } from "./jiterpreter-support";
-import { localHeapViewU8, malloc } from "./memory";
+import { forceThreadMemoryViewRefresh, localHeapViewU8, malloc } from "./memory";
 import { assertNoProxies } from "./gc-handles";
 import { runtimeList } from "./exports";
 import { nativeAbort, nativeExit } from "./run";
@@ -321,6 +321,7 @@ async function onRuntimeInitializedAsync (userOnRuntimeInitialized: (module:Emsc
         await wait_for_all_assets();
 
         if (WasmEnableThreads) {
+            forceThreadMemoryViewRefresh();
             runtimeHelpers.deputyWorker.thread!.postMessageToWorker({
                 type:"deputyThread",
                 cmd: MainToWorkerMessageType.allAssetsLoaded,

src/mono/llvm/llvm-init.proj

@@ -13,7 +13,6 @@
     <MonoLLVMToolsVersion Condition="'$(MonoLLVMHostOS)' == 'linux-musl'">$(runtimelinuxmuslx64MicrosoftNETCoreRuntimeMonoLLVMToolsVersion)</MonoLLVMToolsVersion>
     <MonoLLVMToolsVersion Condition="'$(MonoLLVMHostOS)' == 'win'">$(runtimewinx64MicrosoftNETCoreRuntimeMonoLLVMToolsVersion)</MonoLLVMToolsVersion>
     <MonoLLVMToolsVersion Condition="'$(MonoLLVMHostOS)' == 'osx'">$(runtimeosxx64MicrosoftNETCoreRuntimeMonoLLVMToolsVersion)</MonoLLVMToolsVersion>
-    <MonoLLVMSDKDebugSuffix Condition="'$(MonoLLVMHostOS)' == 'win' and '$(Configuration)' == 'Debug'" >.Debug</MonoLLVMSDKDebugSuffix>
   </PropertyGroup>
 
   <ItemGroup>

src/mono/mono/utils/CMakeLists.txt

@@ -30,8 +30,10 @@ set(utils_unix_sources
 
 if(HOST_WIN32)
     set(utils_platform_sources ${utils_win32_sources})
-elseif(HOST_WASM)
+elseif(HOST_WASM AND DISABLE_THREADS)
     set(utils_platform_sources ${utils_unix_sources} mono-threads-wasm.S)
+elseif(HOST_WASM AND NOT DISABLE_THREADS)
+    set(utils_platform_sources ${utils_unix_sources} mono-threads-wasm.S mono-threads-wasm-MT.S)
 else()
     set(utils_platform_sources ${utils_unix_sources})
 endif()

src/mono/mono/utils/mono-memory-model.h

@@ -13,6 +13,10 @@
 
 #include <config.h>
 
+#ifdef HOST_WASI
+void wasm_atomic_fence(void);
+#endif
+
 #if _MSC_VER
 #ifndef WIN32_LEAN_AND_MEAN
 #define WIN32_LEAN_AND_MEAN
@@ -41,6 +45,9 @@ mono_memory_barrier (void)
 static inline void
 mono_memory_barrier (void)
 {
+#ifdef HOST_WASI
+	wasm_atomic_fence ();
+#endif
 	__sync_synchronize ();
 }
 

src/mono/mono/utils/mono-threads-wasm-MT.S

@@ -0,0 +1,12 @@
+.globl wasm_atomic_fence
+
+.globaltype __stack_pointer, i32
+
+# simulate atomic.fence
+wasm_atomic_fence:
+  .functype wasm_atomic_fence () -> ()
+  global.get __stack_pointer
+  i32.const 0
+  i32.atomic.rmw.or 0
+  drop
+  end_function

src/mono/mono/utils/mono-threads-wasm.c

@@ -24,7 +24,11 @@
 #include <emscripten/threading.h>
 #include <mono/metadata/threads-types.h>
 #endif
-
+#else
+void
+wasm_atomic_fence (void)
+{
+}
 #endif
 
 uintptr_t get_wasm_stack_high(void);
@@ -311,6 +315,9 @@ mono_threads_platform_in_critical_region (THREAD_INFO_TYPE *info)
 void
 mono_memory_barrier_process_wide (void)
 {
+#ifndef DISABLE_THREADS
+	mono_memory_barrier ();
+#endif
 }
 
 #ifdef HOST_BROWSER

src/mono/wasi/wasi.proj

@@ -240,6 +240,7 @@
       <CMakeBuildRuntimeConfigureCmd Condition="'$(WasmEnableSIMD)' == 'true'">$(CMakeBuildRuntimeConfigureCmd) -DCONFIGURATION_COMPILE_OPTIONS=&quot;-msimd128&quot; -DCONFIGURATION_INTERPSIMDTABLES_LIB=&quot;simd&quot;</CMakeBuildRuntimeConfigureCmd>
       <CMakeBuildRuntimeConfigureCmd Condition="'$(WasmEnableSIMD)' != 'true'">$(CMakeBuildRuntimeConfigureCmd) -DCONFIGURATION_INTERPSIMDTABLES_LIB=&quot;nosimd&quot;</CMakeBuildRuntimeConfigureCmd>
       <CMakeBuildRuntimeConfigureCmd Condition="'$(WasmEnableThreads)' == 'true'">$(CMakeBuildRuntimeConfigureCmd) -DDISABLE_THREADS=0</CMakeBuildRuntimeConfigureCmd>
+      <CMakeBuildRuntimeConfigureCmd Condition="'$(WasmEnableThreads)' != 'true'">$(CMakeBuildRuntimeConfigureCmd) -DDISABLE_THREADS=1</CMakeBuildRuntimeConfigureCmd>
       <CMakeBuildRuntimeConfigureCmd Condition="'$(OS)' == 'Windows_NT'">call &quot;$(RepositoryEngineeringDir)native\init-vs-env.cmd&quot; wasm &amp;&amp; $(CMakeBuildRuntimeConfigureCmd)</CMakeBuildRuntimeConfigureCmd>
 
       <CMakeOptions Condition="'$(MonoVerboseBuild)' != ''">-v</CMakeOptions>