Implement wasi thread using thread manager

This is a simple implementation for now; going forward we most likely won't
need to rely on thread manager as it doesn't provide much value in this
scenario.

build-scripts/runtime_lib.cmake

@@ -127,6 +127,7 @@ endif ()
 if (WAMR_BUILD_LIB_WASI_THREADS EQUAL 1)
     include (${IWASM_DIR}/libraries/lib-wasi-threads/lib_wasi_threads.cmake)
     # Enable the dependent feature if lib wasi threads is enabled
+    set (WAMR_BUILD_THREAD_MGR 1)
     set (WAMR_BUILD_BULK_MEMORY 1)
     set (WAMR_BUILD_SHARED_MEMORY 1)
 endif ()

core/iwasm/libraries/lib-wasi-threads/lib_wasi_threads_wrapper.c

@@ -3,7 +3,9 @@
  * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
  */
 
+#include "bh_log.h"
 #include "wasmtime_ssp.h"
+#include "thread_manager.h"
 
 #if WASM_ENABLE_INTERP != 0
 #include "wasm_runtime.h"
@@ -13,10 +15,138 @@
 #include "aot_runtime.h"
 #endif
 
+static const char *THREAD_START_FUNCTION = "wasi_thread_start";
+
+typedef struct {
+    /* app's entry function */
+    wasm_function_inst_t start_func;
+    /* arg of the app's entry function */
+    uint32 arg;
+    /* thread id passed to the app */
+    uint32 thread_id;
+} ThreadStartArg;
+
+static uint32
+allocate_thread_id()
+{
+    static korp_mutex thread_global_lock;
+    static uint32 thread_id = 0;
+
+    uint32 id;
+
+    os_mutex_lock(&thread_global_lock);
+    id = thread_id++;
+    os_mutex_unlock(&thread_global_lock);
+    return id;
+}
+
+static void *
+thread_start(void *arg)
+{
+    wasm_exec_env_t exec_env = (wasm_exec_env_t)arg;
+    wasm_module_inst_t module_inst = get_module_inst(exec_env);
+    ThreadStartArg *thread_arg = exec_env->thread_arg;
+    uint32 argv[2];
+
+    wasm_exec_env_set_thread_info(exec_env);
+    argv[0] = thread_arg->thread_id;
+    argv[1] = thread_arg->arg;
+
+    if (!wasm_runtime_call_wasm(exec_env, thread_arg->start_func, 2, argv)) {
+        if (wasm_runtime_get_exception(module_inst))
+            wasm_cluster_spread_exception(exec_env);
+    }
+
+    /* routine exit, destroy instance */
+    wasm_runtime_deinstantiate_internal(module_inst, true);
+
+    wasm_runtime_free(thread_arg);
+
+    return NULL;
+}
+
 static __wasi_errno_t
 thread_spawn_wrapper(wasm_exec_env_t exec_env, uint32 start_arg)
 {
-    return __WASI_ENOSYS;
+    wasm_module_t module = wasm_exec_env_get_module(exec_env);
+    wasm_module_inst_t module_inst = get_module_inst(exec_env);
+    wasm_module_inst_t new_module_inst = NULL;
+    ThreadStartArg *thread_start_arg = NULL;
+    wasm_function_inst_t start_func;
+
+    uint32 stack_size = 8192;
+    int32 ret = -1;
+#if WASM_ENABLE_LIBC_WASI != 0
+    WASIContext *wasi_ctx;
+#endif
+
+    bh_assert(module);
+    bh_assert(module_inst);
+
+#if WASM_ENABLE_INTERP != 0
+    if (module_inst->module_type == Wasm_Module_Bytecode) {
+        stack_size =
+            ((WASMModuleInstance *)module_inst)->default_wasm_stack_size;
+    }
+#endif
+
+#if WASM_ENABLE_AOT != 0
+    if (module_inst->module_type == Wasm_Module_AoT) {
+        stack_size =
+            ((AOTModuleInstance *)module_inst)->default_wasm_stack_size;
+    }
+#endif
+
+    if (!(new_module_inst = wasm_runtime_instantiate_internal(
+              module, true, stack_size, 0, NULL, 0)))
+        return -1;
+
+    wasm_runtime_set_custom_data_internal(
+        new_module_inst, wasm_runtime_get_custom_data(module_inst));
+
+#if WASM_ENABLE_LIBC_WASI != 0
+    wasi_ctx = wasm_runtime_get_wasi_ctx(module_inst);
+    if (wasi_ctx)
+        wasm_runtime_set_wasi_ctx(new_module_inst, wasi_ctx);
+#endif
+
+    start_func = wasm_runtime_lookup_function(new_module_inst,
+                                              THREAD_START_FUNCTION, NULL);
+    if (!start_func) {
+        LOG_ERROR("Failed to find thread start function %s",
+                  THREAD_START_FUNCTION);
+        goto thread_spawn_fail;
+    }
+
+    if (!(thread_start_arg = wasm_runtime_malloc(sizeof(ThreadStartArg)))) {
+        LOG_ERROR("Runtime args allocation failed");
+        goto thread_spawn_fail;
+    }
+
+    thread_start_arg->thread_id = allocate_thread_id();
+    thread_start_arg->arg = (uint32)start_arg;
+    thread_start_arg->start_func = start_func;
+
+    os_mutex_lock(&exec_env->wait_lock);
+    ret = wasm_cluster_create_thread(exec_env, new_module_inst, thread_start,
+                                     (void *)thread_start_arg);
+    if (ret != 0) {
+        os_mutex_unlock(&exec_env->wait_lock);
+        LOG_ERROR("Failed to spawn a new thread");
+        goto thread_spawn_fail;
+    }
+    os_mutex_unlock(&exec_env->wait_lock);
+
+    return 0;
+
+thread_spawn_fail:
+    if (new_module_inst)
+        wasm_runtime_deinstantiate_internal(new_module_inst, true);
+
+    if (thread_start_arg)
+        wasm_runtime_free(thread_start_arg);
+
+    return -1;
 }
 
 /* clang-format off */