1 /* context_cojava - implementation of context switching for java coroutines */
3 /* Copyright 2012. The SimGrid Team.
4 * All rights reserved. */
6 /* This program is free software; you can redistribute it and/or modify it
7 * under the terms of the license (GNU LGPL) which comes with this package. */
10 #include <xbt/function_types.h>
11 #include <simgrid/simix.h>
13 #include "smx_context_cojava.h"
14 #include "jxbt_utilities.h"
15 #include "xbt/dynar.h"
18 //Coroutine methodID/class cache.
20 jmethodID coroutine_init;
21 jmethodID coroutine_yield;
22 jmethodID coroutine_yieldTo;
23 jmethodID coroutine_stop;
24 //Maestro java coroutine
25 jobject cojava_maestro_coroutine;
29 static smx_context_t my_current_context = NULL;
30 static smx_context_t maestro_context = NULL;
33 xbt_dynar_t cojava_processes;
34 static unsigned long int cojava_process_index = 0;
36 extern JavaVM *__java_vm;
38 XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(jmsg);
42 smx_ctx_cojava_factory_create_context(xbt_main_func_t code, int argc,
44 void_pfn_smxprocess_t cleanup_func,
47 static void smx_ctx_cojava_free(smx_context_t context);
48 static void smx_ctx_cojava_suspend(smx_context_t context);
49 static void smx_ctx_cojava_resume(smx_context_t new_context);
50 static void smx_ctx_cojava_runall(void);
51 static void* smx_ctx_cojava_run(void *data);
52 static void smx_ctx_cojava_create_coroutine(smx_ctx_cojava_t context);
53 void SIMIX_ctx_cojava_factory_init(smx_context_factory_t * factory)
55 /* instantiate the context factory */
56 smx_ctx_base_factory_init(factory);
58 (*factory)->create_context = smx_ctx_cojava_factory_create_context;
59 /* Leave default behavior of (*factory)->finalize */
60 (*factory)->free = smx_ctx_cojava_free;
61 (*factory)->stop = smx_ctx_cojava_stop;
62 (*factory)->suspend = smx_ctx_cojava_suspend;
63 (*factory)->runall = smx_ctx_cojava_runall;
64 (*factory)->name = "ctx_cojava_factory";
65 //(*factory)->finalize = smx_ctx_base_factory_finalize;
66 (*factory)->self = smx_ctx_cojava_self;
67 (*factory)->get_data = smx_ctx_base_get_data;
69 global_env = get_current_thread_env();
71 coclass = (*global_env)->FindClass(global_env, "java/dyn/Coroutine");
72 xbt_assert((coclass != NULL), "Can't find java.dyn.Coroutine class.");
73 //Cache the method id we are going to use
74 coroutine_init = (*global_env)->GetMethodID(global_env, coclass, "<init>", "(Ljava/lang/Runnable;)V");
75 xbt_assert((coroutine_init != NULL), "Can't find <init>");
76 coroutine_stop = (*global_env)->GetMethodID(global_env, coclass, "stop", "()V");
77 xbt_assert((coroutine_stop != NULL), "Method not found...");
78 coroutine_yield = (*global_env)->GetStaticMethodID(global_env, coclass, "yield", "()V");
79 xbt_assert((coroutine_yield != NULL), "Method yield not found.");
80 coroutine_yieldTo = (*global_env)->GetStaticMethodID(global_env, coclass, "yieldTo", "(Ljava/dyn/Coroutine;)V");
81 xbt_assert((coroutine_yieldTo != NULL), "Method yieldTo not found.");
83 jclass class_thread = (*global_env)->FindClass(global_env, "java/lang/Thread");
84 xbt_assert((class_thread != NULL), "Can't find java.lang.Thread class");
86 jclass class_coroutine_support = (*global_env)->FindClass(global_env, "java/dyn/CoroutineSupport");
87 xbt_assert((class_coroutine_support != NULL), "Can't find java.dyn.CoroutineSupport class");
88 jmethodID thread_get_current = (*global_env)->GetStaticMethodID(global_env, class_thread, "currentThread", "()Ljava/lang/Thread;");
89 xbt_assert((thread_get_current != NULL), "Can't find Thread.currentThread() method.");
92 * Retrieve maetro coroutine object
95 jthread = (*global_env)->CallStaticObjectMethod(global_env, class_thread, thread_get_current);
96 xbt_assert((jthread != NULL), "Can't find current thread.");
98 jmethodID thread_get_coroutine_support = (*global_env)->GetMethodID(global_env, class_thread, "getCoroutineSupport", "()Ljava/dyn/CoroutineSupport;");
99 xbt_assert((thread_get_coroutine_support != NULL), "Can't find Thread.getCoroutineSupport method");
101 jobject jcoroutine_support;
102 jcoroutine_support = (*global_env)->CallObjectMethod(global_env, jthread, thread_get_coroutine_support);
103 xbt_assert((jcoroutine_support != NULL), "Can't find coroutine support object");
104 //FIXME ? Be careful, might change in the implementation (we are relying on private fields, so...).
105 jfieldID coroutine_support_thread_coroutine = (*global_env)->GetFieldID(global_env, class_coroutine_support, "threadCoroutine", "Ljava/dyn/Coroutine;");
106 xbt_assert((coroutine_support_thread_coroutine != NULL), "Can't find threadCoroutine field");
107 cojava_maestro_coroutine = (jobject)(*global_env)->GetObjectField(global_env, jcoroutine_support, coroutine_support_thread_coroutine);
108 xbt_assert((cojava_maestro_coroutine != NULL), "Can't find the thread coroutine.");
109 cojava_maestro_coroutine = (*global_env)->NewGlobalRef(global_env, cojava_maestro_coroutine);
110 xbt_assert((cojava_maestro_coroutine != NULL), "Can't get a global reference to the thread coroutine.");
112 smx_context_t smx_ctx_cojava_self(void)
114 return my_current_context;
118 smx_ctx_cojava_factory_create_context(xbt_main_func_t code, int argc,
120 void_pfn_smxprocess_t cleanup_func,
123 smx_ctx_cojava_t context = xbt_new0(s_smx_ctx_cojava_t, 1);
124 /* If the user provided a function for the process then use it
125 otherwise is the context for maestro */
128 context->jprocess = (jobject) code;
131 context->jprocess = NULL;
133 context->super.cleanup_func = cleanup_func;
135 context->super.argc = argc;
136 context->super.argv = argv;
137 context->super.code = code;
139 smx_ctx_cojava_run(context);
142 context->jcoroutine = NULL;
143 my_current_context = (smx_context_t)context;
144 maestro_context = (smx_context_t)context;
147 context->super.data = data;
148 return (smx_context_t) context;
151 static void* smx_ctx_cojava_run(void *data) {
152 smx_ctx_cojava_t context = (smx_ctx_cojava_t)data;
153 my_current_context = (smx_context_t)context;
154 //Create the "Process" object if needed.
155 if (context->super.argc <= 0) {
156 smx_ctx_cojava_create_coroutine(context);
158 my_current_context = maestro_context;
161 static void smx_ctx_cojava_free(smx_context_t context)
164 smx_ctx_cojava_t ctx_java = (smx_ctx_cojava_t) context;
165 if (ctx_java->jcoroutine) { /* We are not in maestro context */
166 JNIEnv *env = get_current_thread_env();
167 (*env)->DeleteGlobalRef(env, ctx_java->jcoroutine);
168 (*env)->DeleteGlobalRef(env, ctx_java->jprocess);
171 smx_ctx_base_free(context);
175 void smx_ctx_cojava_stop(smx_context_t context)
178 * The java stack needs to be empty, otherwise weird stuff
181 if (context->iwannadie) {
182 context->iwannadie = 0;
183 JNIEnv *env = get_current_thread_env();
184 jxbt_throw_by_name(env, "org/simgrid/msg/ProcessKilledError", xbt_strdup("Process killed :)"));
185 THROWF(cancel_error, 0, "process cancelled");
188 smx_ctx_base_stop(context);
189 smx_ctx_cojava_suspend(context);
193 static void smx_ctx_cojava_suspend(smx_context_t context)
195 smx_context_t previous_context = context;
196 unsigned long int i = cojava_process_index++;
197 jobject next_coroutine;
199 if (i < xbt_dynar_length(cojava_processes)) {
200 smx_context_t next_context = SIMIX_process_get_context(xbt_dynar_get_as(
201 cojava_processes,i, smx_process_t));
202 my_current_context = next_context;
203 XBT_DEBUG("Switching to %p",my_current_context);
204 smx_ctx_cojava_t java_context = (smx_ctx_cojava_t)(next_context);
205 if (!java_context->jprocess) {
206 java_context->super.code(java_context->super.argc, java_context->super.argv);
207 smx_ctx_cojava_create_coroutine(java_context);
209 else if (!java_context->bound) {
210 java_context->bound = 1;
211 smx_process_t process = SIMIX_process_self();
212 (*global_env)->SetLongField(global_env, java_context->jprocess,
213 jprocess_field_Process_bind,
217 next_coroutine = java_context->jcoroutine;
220 //Give maestro the control back.
221 next_coroutine = cojava_maestro_coroutine;
222 my_current_context = maestro_context;
224 (*global_env)->CallStaticVoidMethod(global_env, coclass, coroutine_yieldTo, next_coroutine);
225 my_current_context = previous_context;
228 static void smx_ctx_cojava_resume(smx_context_t new_context) {
229 my_current_context = new_context;
230 smx_ctx_cojava_t java_context = (smx_ctx_cojava_t)(new_context);
232 if (!java_context->jprocess) {
233 java_context->super.code(java_context->super.argc, java_context->super.argv);
234 smx_ctx_cojava_create_coroutine(java_context);
235 java_context->bound = 1;
237 else if (!java_context->bound) {
238 java_context->bound = 1;
239 smx_process_t process = SIMIX_process_self();
240 (*global_env)->SetLongField(global_env, java_context->jprocess,
241 jprocess_field_Process_bind, (intptr_t)process);
243 (*global_env)->CallStaticVoidMethod(global_env, coclass, coroutine_yieldTo, java_context->jcoroutine);
246 static void smx_ctx_cojava_runall(void)
248 cojava_processes = SIMIX_process_get_runnable();
249 smx_process_t process;
250 if (!xbt_dynar_is_empty(cojava_processes)) {
251 process = xbt_dynar_get_as(cojava_processes, 0, smx_process_t);
252 cojava_process_index = 1;
253 /* Execute the first process */
254 smx_ctx_cojava_resume(SIMIX_process_get_context(process));
258 static void smx_ctx_cojava_create_coroutine(smx_ctx_cojava_t context) {
259 JNIEnv *env = get_current_thread_env();
260 jclass coclass = (*env)->FindClass(env, "java/dyn/Coroutine");
261 xbt_assert((coclass != NULL), "Can't find coroutine class ! :(");
262 jobject jcoroutine = (*env)->NewObject(env, coclass, coroutine_init, context->jprocess);
263 if (jcoroutine == NULL) {
264 FILE *conf= fopen("/proc/sys/vm/max_map_count","r");
267 fscanf(conf,"%d",&limit);
269 if (limit!=-1 && SIMIX_process_count() > (limit - 100) /2)
270 xbt_die("Error while creating a new coroutine. "
271 "This seem due to the the vm.max_map_count system limit that is only equal to %d while we already have %d coroutines. "
272 "Please check the install documentation to see how to increase this limit", limit, SIMIX_process_count());
274 xbt_die("Error while creating a new coroutine. "
275 "This seems to be a non-linux system, disabling the automatic verification that the system limit on the amount of memory maps is high enough.");
276 xbt_die("Error while creating a new coroutine. ");
281 jcoroutine = (*env)->NewGlobalRef(env, jcoroutine);
282 context->jcoroutine = jcoroutine;