src/smx_context_cojava.c

   1 /* context_cojava - implementation of context switching for java coroutines */
   2
   3 /* Copyright 2012. The SimGrid Team.
   4  * All rights reserved.                                                     */
   5
   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. */
   8
   9
  10 #include <xbt/function_types.h>
  11 #include <simgrid/simix.h>
  12 #include <xbt/ex.h>
  13 #include "smx_context_cojava.h"
  14 #include "jxbt_utilities.h"
  15 #include "xbt/dynar.h"
  16
  17
  18 //Coroutine methodID/class cache.
  19 jclass coclass;
  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;
  26
  27 JNIEnv *global_env;
  28
  29 static smx_context_t my_current_context = NULL;
  30 static smx_context_t maestro_context = NULL;
  31
  32
  33 xbt_dynar_t cojava_processes;
  34 static unsigned long int cojava_process_index = 0;
  35
  36 extern JavaVM *__java_vm;
  37
  38 XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(jmsg);
  39
  40
  41 static smx_context_t
  42 smx_ctx_cojava_factory_create_context(xbt_main_func_t code, int argc,
  43                                     char **argv,
  44                                     void_pfn_smxprocess_t cleanup_func,
  45                                     void *data);
  46
  47 static void smx_ctx_cojava_free(smx_context_t context);
  48 static void smx_ctx_cojava_start(smx_context_t context);
  49 static void smx_ctx_cojava_suspend(smx_context_t context);
  50 static void smx_ctx_cojava_resume(smx_context_t new_context);
  51 static void smx_ctx_cojava_runall(void);
  52 static void* smx_ctx_cojava_run(void *data);
  53 static void smx_ctx_cojava_create_coroutine(smx_ctx_cojava_t context);
  54 void SIMIX_ctx_cojava_factory_init(smx_context_factory_t * factory)
  55 {
  56   /* instantiate the context factory */
  57   smx_ctx_base_factory_init(factory);
  58
  59   (*factory)->create_context = smx_ctx_cojava_factory_create_context;
  60   /* Leave default behavior of (*factory)->finalize */
  61   (*factory)->free = smx_ctx_cojava_free;
  62   (*factory)->stop = smx_ctx_cojava_stop;
  63   (*factory)->suspend = smx_ctx_cojava_suspend;
  64   (*factory)->runall = smx_ctx_cojava_runall;
  65   (*factory)->name = "ctx_cojava_factory";
  66   //(*factory)->finalize = smx_ctx_base_factory_finalize;
  67   (*factory)->self = smx_ctx_cojava_self;
  68   (*factory)->get_data = smx_ctx_base_get_data;
  69
  70   global_env = get_current_thread_env();
  71
  72   coclass = (*global_env)->FindClass(global_env, "java/dyn/Coroutine");
  73   xbt_assert((coclass != NULL), "Can't find java.dyn.Coroutine class.");
  74   //Cache the method id we are going to use
  75   coroutine_init = (*global_env)->GetMethodID(global_env, coclass, "<init>", "(Ljava/lang/Runnable;)V");
  76   xbt_assert((coroutine_init != NULL), "Can't find <init>");
  77   coroutine_stop = (*global_env)->GetMethodID(global_env, coclass, "stop", "()V");
  78   xbt_assert((coroutine_stop != NULL), "Method not found...");
  79   coroutine_yield = (*global_env)->GetStaticMethodID(global_env, coclass, "yield", "()V");
  80         xbt_assert((coroutine_yield != NULL), "Method yield not found.");
  81         coroutine_yieldTo = (*global_env)->GetStaticMethodID(global_env, coclass, "yieldTo", "(Ljava/dyn/Coroutine;)V");
  82         xbt_assert((coroutine_yieldTo != NULL), "Method yieldTo not found.");
  83
  84         jclass class_thread = (*global_env)->FindClass(global_env, "java/lang/Thread");
  85         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.");
  90
  91         /**
  92          * Retrieve maetro coroutine object
  93          */
  94         jobject jthread;
  95         jthread = (*global_env)->CallStaticObjectMethod(global_env, class_thread, thread_get_current);
  96         xbt_assert((jthread != NULL), "Can't find current thread.");
  97
  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");
 100
 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.");
 111 }
 112 smx_context_t smx_ctx_cojava_self(void)
 113 {
 114         return my_current_context;
 115 }
 116
 117 static smx_context_t
 118 smx_ctx_cojava_factory_create_context(xbt_main_func_t code, int argc,
 119                                     char **argv,
 120                                     void_pfn_smxprocess_t cleanup_func,
 121                                     void* data)
 122 {
 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 */
 126   if (code) {
 127                 if (argc == 0) {
 128                         context->jprocess = (jobject) code;
 129                 }
 130                 else {
 131                         context->jprocess = NULL;
 132                 }
 133                 context->super.cleanup_func = cleanup_func;
 134
 135                 context->super.argc = argc;
 136                 context->super.argv = argv;
 137                 context->super.code = code;
 138
 139                 smx_ctx_cojava_run(context);
 140   }
 141   else {
 142         context->jcoroutine = NULL;
 143         my_current_context = (smx_context_t)context;
 144         maestro_context = (smx_context_t)context;
 145   }
 146   context->bound = 0;
 147   context->super.data = data;
 148   return (smx_context_t) context;
 149 }
 150
 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);
 157         }
 158         my_current_context = maestro_context;
 159   return NULL;
 160 }
 161 static void smx_ctx_cojava_free(smx_context_t context)
 162 {
 163         if (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);
 169                 }
 170   }
 171   smx_ctx_base_free(context);
 172 }
 173
 174
 175 void smx_ctx_cojava_stop(smx_context_t context)
 176 {
 177         /*
 178          * The java stack needs to be empty, otherwise weird stuff
 179          * will happen
 180          */
 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", bprintf("Process killed :)"));
 185         THROWF(cancel_error, 0, "process cancelled");
 186   }
 187         else {
 188                 smx_ctx_base_stop(context);
 189                 smx_ctx_cojava_suspend(context);
 190         }
 191 }
 192
 193 static void smx_ctx_cojava_suspend(smx_context_t context)
 194 {
 195         smx_context_t previous_context = context;
 196         unsigned long int i = cojava_process_index++;
 197         jobject next_coroutine;
 198
 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
 206                 if (!java_context->jprocess) {
 207                         (*(java_context->super.code))(java_context->super.argc, java_context->super.argv);
 208                         smx_ctx_cojava_create_coroutine(java_context);
 209                 }
 210                 else if (!java_context->bound) {
 211                         java_context->bound = 1;
 212                         smx_process_t process = SIMIX_process_self();
 213                         (*global_env)->SetLongField(global_env, java_context->jprocess, jprocess_field_Process_bind, (jlong)process);
 214                 }
 215
 216                 next_coroutine = java_context->jcoroutine;
 217         }
 218         else {
 219                 //Give maestro the control back.
 220                 next_coroutine = cojava_maestro_coroutine;
 221                 my_current_context = maestro_context;
 222         }
 223   (*global_env)->CallStaticVoidMethod(global_env, coclass, coroutine_yieldTo, next_coroutine);
 224   my_current_context = previous_context;
 225 }
 226
 227 static void smx_ctx_cojava_resume(smx_context_t new_context) {
 228         my_current_context = new_context;
 229         smx_ctx_cojava_t java_context = (smx_ctx_cojava_t)(new_context);
 230
 231         if (!java_context->jprocess) {
 232                 (*(java_context->super.code))(java_context->super.argc, java_context->super.argv);
 233                 smx_ctx_cojava_create_coroutine(java_context);
 234                 java_context->bound = 1;
 235         }
 236         else if (!java_context->bound) {
 237                 java_context->bound = 1;
 238                 smx_process_t process = SIMIX_process_self();
 239                 (*global_env)->SetLongField(global_env, java_context->jprocess, jprocess_field_Process_bind, (jlong)process);
 240         }
 241   (*global_env)->CallStaticVoidMethod(global_env, coclass, coroutine_yieldTo, java_context->jcoroutine);
 242 }
 243
 244 static void smx_ctx_cojava_runall(void)
 245 {
 246   cojava_processes = SIMIX_process_get_runnable();
 247         smx_process_t process;
 248         process = xbt_dynar_get_as(cojava_processes, 0, smx_process_t);
 249         cojava_process_index = 1;
 250         /* Execute the first process */
 251         smx_ctx_cojava_resume(SIMIX_process_get_context(process));
 252 }
 253
 254 static void smx_ctx_cojava_create_coroutine(smx_ctx_cojava_t context) {
 255         JNIEnv *env = get_current_thread_env();
 256         jclass coclass = (*env)->FindClass(env, "java/dyn/Coroutine");
 257   xbt_assert((coclass != NULL), "Can't find coroutine class ! :(");
 258   jobject jcoroutine = (*env)->NewObject(env, coclass, coroutine_init, context->jprocess);
 259   xbt_assert((jcoroutine != NULL), "Can't create coroutine object.");
 260   jcoroutine = (*env)->NewGlobalRef(env, jcoroutine);
 261   context->jcoroutine = jcoroutine;
 262 }