+/* context_cojava - implementation of context switching for java coroutines */
+
+/* Copyright 2012. The SimGrid Team.
+ * All rights reserved. */
+
+/* This program is free software; you can redistribute it and/or modify it
+ * under the terms of the license (GNU LGPL) which comes with this package. */
+
+
+#include <xbt/function_types.h>
+#include <simgrid/simix.h>
+#include <xbt/ex.h>
+#include "smx_context_cojava.h"
+#include "jxbt_utilities.h"
+#include "xbt/dynar.h"
+
+
+//Coroutine methodID/class cache.
+jclass coclass;
+jmethodID coroutine_init;
+jmethodID coroutine_yield;
+jmethodID coroutine_yieldTo;
+jmethodID coroutine_stop;
+//Maestro java coroutine
+jobject cojava_maestro_coroutine;
+
+JNIEnv *global_env;
+
+static smx_context_t my_current_context = NULL;
+static smx_context_t maestro_context = NULL;
+
+
+xbt_dynar_t cojava_processes;
+static unsigned long int cojava_process_index = 0;
+
+static JavaVM *get_current_vm(void);
+static JavaVM *get_current_vm(void)
+{
+ JavaVM *jvm;
+ JNI_GetCreatedJavaVMs(&jvm,1,NULL);
+ return jvm;
+}
+
+XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(jmsg);
+
+
+static smx_context_t
+smx_ctx_cojava_factory_create_context(xbt_main_func_t code, int argc,
+ char **argv,
+ void_pfn_smxprocess_t cleanup_func,
+ void *data);
+
+static void smx_ctx_cojava_free(smx_context_t context);
+static void smx_ctx_cojava_start(smx_context_t context);
+static void smx_ctx_cojava_suspend(smx_context_t context);
+static void smx_ctx_cojava_resume(smx_context_t new_context);
+static void smx_ctx_cojava_runall(void);
+static void* smx_ctx_cojava_run(void *data);
+static void smx_ctx_cojava_create_coroutine(smx_ctx_cojava_t context);
+void SIMIX_ctx_cojava_factory_init(smx_context_factory_t * factory)
+{
+ /* instantiate the context factory */
+ smx_ctx_base_factory_init(factory);
+
+ (*factory)->create_context = smx_ctx_cojava_factory_create_context;
+ /* Leave default behavior of (*factory)->finalize */
+ (*factory)->free = smx_ctx_cojava_free;
+ (*factory)->stop = smx_ctx_cojava_stop;
+ (*factory)->suspend = smx_ctx_cojava_suspend;
+ (*factory)->runall = smx_ctx_cojava_runall;
+ (*factory)->name = "ctx_cojava_factory";
+ //(*factory)->finalize = smx_ctx_base_factory_finalize;
+ (*factory)->self = smx_ctx_cojava_self;
+ (*factory)->get_data = smx_ctx_base_get_data;
+
+ global_env = get_current_thread_env();
+
+ coclass = (*global_env)->FindClass(global_env, "java/dyn/Coroutine");
+ xbt_assert((coclass != NULL), "Can't find java.dyn.Coroutine class.");
+ //Cache the method id we are going to use
+ coroutine_init = (*global_env)->GetMethodID(global_env, coclass, "<init>", "(Ljava/lang/Runnable;)V");
+ xbt_assert((coroutine_init != NULL), "Can't find <init>");
+ coroutine_stop = (*global_env)->GetMethodID(global_env, coclass, "stop", "()V");
+ xbt_assert((coroutine_stop != NULL), "Method not found...");
+ coroutine_yield = (*global_env)->GetStaticMethodID(global_env, coclass, "yield", "()V");
+ xbt_assert((coroutine_yield != NULL), "Method yield not found.");
+ coroutine_yieldTo = (*global_env)->GetStaticMethodID(global_env, coclass, "yieldTo", "(Ljava/dyn/Coroutine;)V");
+ xbt_assert((coroutine_yieldTo != NULL), "Method yieldTo not found.");
+
+ jclass class_thread = (*global_env)->FindClass(global_env, "java/lang/Thread");
+ xbt_assert((class_thread != NULL), "Can't find java.lang.Thread class");
+ jclass class_coroutine_support = (*global_env)->FindClass(global_env, "java/dyn/CoroutineSupport");
+ xbt_assert((class_coroutine_support != NULL), "Can't find java.dyn.CoroutineSupport class");
+ jmethodID thread_get_current = (*global_env)->GetStaticMethodID(global_env, class_thread, "currentThread", "()Ljava/lang/Thread;");
+ xbt_assert((thread_get_current != NULL), "Can't find Thread.currentThread() method.");
+
+ /**
+ * Retrieve maetro coroutine object
+ */
+ jobject jthread;
+ jthread = (*global_env)->CallStaticObjectMethod(global_env, class_thread, thread_get_current);
+ xbt_assert((jthread != NULL), "Can't find current thread.");
+
+ jmethodID thread_get_coroutine_support = (*global_env)->GetMethodID(global_env, class_thread, "getCoroutineSupport", "()Ljava/dyn/CoroutineSupport;");
+ xbt_assert((thread_get_coroutine_support != NULL), "Can't find Thread.getCoroutineSupport method");
+
+ jobject jcoroutine_support;
+ jcoroutine_support = (*global_env)->CallObjectMethod(global_env, jthread, thread_get_coroutine_support);
+ xbt_assert((jcoroutine_support != NULL), "Can't find coroutine support object");
+ //FIXME ? Be careful, might change in the implementation (we are relying on private fields, so...).
+ jfieldID coroutine_support_thread_coroutine = (*global_env)->GetFieldID(global_env, class_coroutine_support, "threadCoroutine", "Ljava/dyn/Coroutine;");
+ xbt_assert((coroutine_support_thread_coroutine != NULL), "Can't find threadCoroutine field");
+ cojava_maestro_coroutine = (jobject)(*global_env)->GetObjectField(global_env, jcoroutine_support, coroutine_support_thread_coroutine);
+ xbt_assert((cojava_maestro_coroutine != NULL), "Can't find the thread coroutine.");
+ cojava_maestro_coroutine = (*global_env)->NewGlobalRef(global_env, cojava_maestro_coroutine);
+ xbt_assert((cojava_maestro_coroutine != NULL), "Can't get a global reference to the thread coroutine.");
+}
+smx_context_t smx_ctx_cojava_self(void)
+{
+ return my_current_context;
+}
+
+static smx_context_t
+smx_ctx_cojava_factory_create_context(xbt_main_func_t code, int argc,
+ char **argv,
+ void_pfn_smxprocess_t cleanup_func,
+ void* data)
+{
+ smx_ctx_cojava_t context = xbt_new0(s_smx_ctx_cojava_t, 1);
+ /* If the user provided a function for the process then use it
+ otherwise is the context for maestro */
+ if (code) {
+ if (argc == 0) {
+ context->jprocess = (jobject) code;
+ }
+ else {
+ context->jprocess = NULL;
+ }
+ context->super.cleanup_func = cleanup_func;
+
+ context->super.argc = argc;
+ context->super.argv = argv;
+ context->super.code = code;
+
+ smx_ctx_cojava_run(context);
+ }
+ else {
+ context->jcoroutine = NULL;
+ my_current_context = (smx_context_t)context;
+ maestro_context = (smx_context_t)context;
+ }
+ context->bound = 0;
+ context->super.data = data;
+ return (smx_context_t) context;
+}
+
+static void* smx_ctx_cojava_run(void *data) {
+ smx_ctx_cojava_t context = (smx_ctx_cojava_t)data;
+ my_current_context = (smx_context_t)context;
+ //Create the "Process" object if needed.
+ if (context->super.argc <= 0) {
+ smx_ctx_cojava_create_coroutine(context);
+ }
+ my_current_context = maestro_context;
+ return NULL;
+}
+static void smx_ctx_cojava_free(smx_context_t context)
+{
+ if (context) {
+ smx_ctx_cojava_t ctx_java = (smx_ctx_cojava_t) context;
+ if (ctx_java->jcoroutine) { /* We are not in maestro context */
+ JNIEnv *env = get_current_thread_env();
+ (*env)->DeleteGlobalRef(env, ctx_java->jcoroutine);
+ (*env)->DeleteGlobalRef(env, ctx_java->jprocess);
+ }
+ }
+ smx_ctx_base_free(context);
+}
+
+
+void smx_ctx_cojava_stop(smx_context_t context)
+{
+ /*
+ * The java stack needs to be empty, otherwise weird stuff
+ * will happen
+ */
+ if (context->iwannadie == -1) {
+ context->iwannadie = 0;
+ JNIEnv *env = get_current_thread_env();
+ jxbt_throw_by_name(env, "org/simgrid/msg/ProcessKilledError", bprintf("Process killed :)"));
+ THROWF(cancel_error, 0, "process cancelled");
+ }
+ else {
+ smx_ctx_base_stop(context);
+ smx_ctx_cojava_suspend(context);
+ }
+}
+
+static void smx_ctx_cojava_suspend(smx_context_t context)
+{
+ smx_context_t previous_context = context;
+ unsigned long int i = cojava_process_index++;
+ jobject next_coroutine;
+
+ if (i < xbt_dynar_length(cojava_processes)) {
+ smx_context_t next_context = SIMIX_process_get_context(xbt_dynar_get_as(
+ cojava_processes,i, smx_process_t));
+ my_current_context = next_context;
+ XBT_DEBUG("Switching to %p",my_current_context);
+ smx_ctx_cojava_t java_context = (smx_ctx_cojava_t)(next_context);
+
+ if (!java_context->jprocess) {
+ (*(java_context->super.code))(java_context->super.argc, java_context->super.argv);
+ smx_ctx_cojava_create_coroutine(java_context);
+ }
+ else if (!java_context->bound) {
+ java_context->bound = 1;
+ smx_process_t process = SIMIX_process_self();
+ (*global_env)->SetLongField(global_env, java_context->jprocess, jprocess_field_Process_bind, (jlong)process);
+ }
+
+ next_coroutine = java_context->jcoroutine;
+ }
+ else {
+ //Give maestro the control back.
+ next_coroutine = cojava_maestro_coroutine;
+ my_current_context = maestro_context;
+ }
+ (*global_env)->CallStaticVoidMethod(global_env, coclass, coroutine_yieldTo, next_coroutine);
+ my_current_context = previous_context;
+}
+
+static void smx_ctx_cojava_resume(smx_context_t new_context) {
+ my_current_context = new_context;
+ smx_ctx_cojava_t java_context = (smx_ctx_cojava_t)(new_context);
+
+ if (!java_context->jprocess) {
+ (*(java_context->super.code))(java_context->super.argc, java_context->super.argv);
+ smx_ctx_cojava_create_coroutine(java_context);
+ java_context->bound = 1;
+ }
+ else if (!java_context->bound) {
+ java_context->bound = 1;
+ smx_process_t process = SIMIX_process_self();
+ (*global_env)->SetLongField(global_env, java_context->jprocess, jprocess_field_Process_bind, (jlong)process);
+ }
+ (*global_env)->CallStaticVoidMethod(global_env, coclass, coroutine_yieldTo, java_context->jcoroutine);
+}
+
+static void smx_ctx_cojava_runall(void)
+{
+ cojava_processes = SIMIX_process_get_runnable();
+ smx_process_t process;
+ process = xbt_dynar_get_as(cojava_processes, 0, smx_process_t);
+ cojava_process_index = 1;
+ /* Execute the first process */
+ smx_ctx_cojava_resume(SIMIX_process_get_context(process));
+}
+
+static void smx_ctx_cojava_create_coroutine(smx_ctx_cojava_t context) {
+ JNIEnv *env = get_current_thread_env();
+ jclass coclass = (*env)->FindClass(env, "java/dyn/Coroutine");
+ xbt_assert((coclass != NULL), "Can't find coroutine class ! :(");
+ jobject jcoroutine = (*env)->NewObject(env, coclass, coroutine_init, context->jprocess);
+ xbt_assert((jcoroutine != NULL), "Can't create coroutine object.");
+ jcoroutine = (*env)->NewGlobalRef(env, jcoroutine);
+ context->jcoroutine = jcoroutine;
+}
