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Bugfix: Protect SIMIX_process_self in the case that the context module is not yet...
[simgrid.git] / src / simix / smx_process.c
index fa1fc66..f22b2cc 100644 (file)
@@ -1,6 +1,5 @@
-//*     $Id$     */
-
-/* Copyright (c) 2002,2003,2004 Arnaud Legrand. All rights reserved.        */
+/* Copyright (c) 2007, 2008, 2009, 2010. 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/log.h"
 #include "xbt/dict.h"
 #include "msg/mailbox.h"
+#include "mc/mc.h"
 
 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(simix_process, simix,
-                               "Logging specific to SIMIX (process)");
+                                "Logging specific to SIMIX (process)");
+
+static unsigned long simix_process_count = 0;
 
-/******************************** Process ************************************/
 /**
- * \brief Creates and runs a new #smx_process_t.
+ * \brief Returns the current agent.
+ *
+ * This functions returns the currently running SIMIX process.
  *
- * Does exactly the same as #SIMIX_process_create_with_arguments but without 
-   providing standard arguments (\a argc, \a argv).
- * \see SIMIX_process_create_with_arguments
+ * \return The SIMIX process
  */
+XBT_INLINE smx_process_t SIMIX_process_self(void)
+{
+  smx_context_t self_context = SIMIX_context_self();
 
+  return self_context ? SIMIX_context_get_data(self_context) : NULL;
+}
 
-void SIMIX_process_cleanup(void *arg)
+/**
+ * \brief Move a process to the list of processes to destroy.
+ */
+void SIMIX_process_cleanup(smx_process_t process)
 {
-  xbt_swag_remove(arg, simix_global->process_list);
-  xbt_swag_remove(arg, simix_global->process_to_run);
-  xbt_swag_remove(arg,
-                 ((smx_process_t) arg)->simdata->smx_host->simdata->
-                 process_list);
-  free(((smx_process_t) arg)->name);
-  ((smx_process_t) arg)->name = NULL;
-
-  free(((smx_process_t) arg)->simdata);
-  ((smx_process_t) arg)->simdata = NULL;
-  free(arg);
+  DEBUG1("Cleanup process %s", process->name);
+  xbt_swag_remove(process, simix_global->process_to_run);
+  xbt_swag_remove(process, simix_global->process_list);
+  xbt_swag_remove(process, process->smx_host->process_list);
+  xbt_swag_insert(process, simix_global->process_to_destroy);
 }
 
 /** 
- * \brief Creates and runs a new #smx_process_t.
- *
- * A constructor for #m_process_t taking four arguments and returning the corresponding object. The structure (and the corresponding thread) is created, and put in the list of ready process.
+ * Garbage collection
  *
- * \param name a name for the object. It is for user-level information and can be NULL.
-* \param data a pointer to any data one may want to attach to the new object.  It is for user-level information and can be NULL. It can be retrieved with the function \ref MSG_process_get_data.
- * \param host the location where the new agent is executed.
- * \param argc first argument passed to \a code
- * \param argv second argument passed to \a code
- * \param clean_process_function The cleanup function of user process. It will be called when the process finish. This function have to call the SIMIX_process_cleanup.        
- * \see smx_process_t
- * \return The new corresponding object.
+ * Should be called some time to time to free the memory allocated for processes
+ * that have finished (or killed).
  */
-smx_process_t SIMIX_process_create(const char *name,
-                                  xbt_main_func_t code, void *data,
-                                  const char *hostname, int argc,
-                                  char **argv, xbt_dict_t properties)
+void SIMIX_process_empty_trash(void)
 {
-  smx_simdata_process_t simdata = xbt_new0(s_smx_simdata_process_t, 1);
-  smx_process_t process = xbt_new0(s_smx_process_t, 1);
-  smx_process_t self = NULL;
-  smx_host_t host = SIMIX_host_get_by_name(hostname);
-  /*char alias[MAX_ALIAS_NAME + 1] = {0};
-  msg_mailbox_t mailbox;*/
-       
-  xbt_assert0(((code != NULL) && (host != NULL)), "Invalid parameters");
-  /* Simulator Data */
-
-  simdata->smx_host = host;
-  simdata->mutex = NULL;
-  simdata->cond = NULL;
-  simdata->argc = argc;
-  simdata->argv = argv;
-  simdata->context = xbt_context_new(name,code, NULL, NULL,
-                                    simix_global->
-                                    cleanup_process_function, process,
-                                    simdata->argc, simdata->argv);
-
-  /* Process structure */
-  process->name = xbt_strdup(name);
-  process->simdata = simdata;
-  process->data = data;
+  smx_process_t process = NULL;
 
-  /* Add properties*/
-  simdata->properties = properties;
+  while ((process = xbt_swag_extract(simix_global->process_to_destroy))) {
+    SIMIX_context_free(process->context);
 
-  xbt_swag_insert(process, host->simdata->process_list);
+    /* Free the exception allocated at creation time */
+    if (process->running_ctx)
+      free(process->running_ctx);
+    if (process->properties)
+      xbt_dict_free(&process->properties);
 
-  /* fix current_process, about which xbt_context_start mocks around */
-  self = simix_global->current_process;
-  xbt_context_start(process->simdata->context);
-  simix_global->current_process = self;
+    free(process->name);
+    process->name = NULL;
+    free(process);
+  }
+}
 
-  xbt_swag_insert(process, simix_global->process_list);
-  DEBUG2("Inserting %s(%s) in the to_run list", process->name, host->name);
-  xbt_swag_insert(process, simix_global->process_to_run);
-  
-  /*sprintf(alias,"%s:%s",hostname,process->name);
+/**
+ * \brief Creates and runs the maestro process
+ */
+void SIMIX_create_maestro_process()
+{
+  smx_process_t maestro = NULL;
+
+  /* Create maestro process and intilialize it */
+  maestro = xbt_new0(s_smx_process_t, 1);
+  maestro->pid = simix_process_count++;
+  maestro->name = (char *) "";
+  maestro->running_ctx = xbt_new(xbt_running_ctx_t, 1);
+  XBT_RUNNING_CTX_INITIALIZE(maestro->running_ctx);
+  maestro->context = SIMIX_context_new(NULL, 0, NULL, NULL, maestro);
+
+  simix_global->maestro_process = maestro;
+  return;
+}
 
-       mailbox = MSG_mailbox_new(alias);
-       MSG_mailbox_set_hostname(mailbox, hostname);*/
+/**
+ * \brief Same as SIMIX_process_create() but with only one argument (used by timers).
+ * \return the process created
+ */
+smx_process_t SIMIX_process_create_from_wrapper(smx_process_arg_t args) {
+
+  smx_process_t process;
+
+  if (simix_global->create_process_function) {
+    process = simix_global->create_process_function(args->name,
+       args->code,
+       args->data,
+       args->hostname,
+       args->argc,
+       args->argv,
+       args->properties);
+  }
+  else {
+    process = SIMIX_process_create(args->name,
+       args->code,
+       args->data,
+       args->hostname,
+       args->argc,
+       args->argv,
+       args->properties);
+  }
+  // FIXME: to simplify this, simix_global->create_process_function could just
+  // be SIMIX_process_create() by default (and the same thing in smx_deployment.c)
 
   return process;
 }
-/** 
- * \brief Creates and runs a new #smx_process_t hosting a JAVA thread
+
+/**
+ * \brief Internal function to create a process.
+ *
+ * This function actually creates the process.
+ * It may be called when a REQ_PROCESS_CREATE request occurs,
+ * or directly for SIMIX internal purposes.
  *
- * Warning: this should only be used in libsimgrid4java, since it create
- * a context with no code, which leads to segfaults in plain libsimgrid 
+ * \return the process created
  */
-void SIMIX_jprocess_create(const char *name, smx_host_t host,
-                          void *data,
-                          void *jprocess, void *jenv, smx_process_t * res)
-{
-  smx_simdata_process_t simdata = xbt_new0(s_smx_simdata_process_t, 1);
-  smx_process_t process = xbt_new0(s_smx_process_t, 1);
-  smx_process_t self = NULL;
-
-  /* HACK: We need this trick because when we xbt_context_new() do
-     syncronization stuff, the s_process field in the m_process needs 
-     to have a valid value, and we call xbt_context_new() before 
-     returning, of course, ie, before providing a right value to the 
-     caller (Java_simgrid_msg_Msg_processCreate) have time to store it  
-     in place. This way, we initialize the m_process->simdata->s_process 
-     field ourself ASAP.
-
-     All this would be much simpler if the synchronization stuff would be done
-     in the JAVA world, I think.
-   */
-  *res = process;
-
-
-
-  DEBUG5("jprocess_create(name=%s,host=%p,data=%p,jproc=%p,jenv=%p)",
-        name, host, data, jprocess, jenv);
-  xbt_assert0(host, "Invalid parameters");
-  /* Simulator Data */
-  simdata->smx_host = host;
-  simdata->mutex = NULL;
-  simdata->cond = NULL;
-  simdata->argc = 0;
-  simdata->argv = NULL;
-
-  simdata->context = xbt_context_new(name,NULL, NULL, jprocess,
-                                    simix_global->
-                                    cleanup_process_function, process,
-                                    /* argc/argv */ 0, NULL);
-       
-  /* Process structure */
-  process->name = xbt_strdup(name);
-  process->simdata = simdata;
-  process->data = data;
+smx_process_t SIMIX_process_create(const char *name,
+                                   xbt_main_func_t code,
+                                  void *data,
+                                  const char *hostname,
+                                  int argc, char **argv,
+                                  xbt_dict_t properties) {
 
-  xbt_swag_insert(process, host->simdata->process_list);
+  smx_process_t process = NULL;
+  smx_host_t host = SIMIX_host_get_by_name(hostname);
 
-  /* fix current_process, about which xbt_context_start mocks around */
-  self = simix_global->current_process;
-  xbt_context_start(process->simdata->context);
-  simix_global->current_process = self;
+  DEBUG2("Start process %s on host %s", name, hostname);
 
-  xbt_swag_insert(process, simix_global->process_list);
-  DEBUG2("Inserting %s(%s) in the to_run list", process->name, host->name);
-  xbt_swag_insert(process, simix_global->process_to_run);
+  if (!SIMIX_host_get_state(host)) {
+    WARN2("Cannot launch process '%s' on failed host '%s'", name,
+          hostname);
+  }
+  else {
+    process = xbt_new0(s_smx_process_t, 1);
 
-}
+    xbt_assert0(((code != NULL) && (host != NULL)), "Invalid parameters");
+
+    /* Process data */
+    process->pid = simix_process_count++;
+    process->name = xbt_strdup(name);
+    process->smx_host = host;
+    process->data = data;
+
+    VERB1("Create context %s", process->name);
+    process->context = SIMIX_context_new(code, argc, argv,
+       simix_global->cleanup_process_function, process);
+
+    process->running_ctx = xbt_new(xbt_running_ctx_t, 1);
+    XBT_RUNNING_CTX_INITIALIZE(process->running_ctx);
+
+    /* Add properties */
+    process->properties = properties;
+
+    /* Add the process to it's host process list */
+    xbt_swag_insert(process, host->process_list);
+
+    DEBUG1("Start context '%s'", process->name);
+
+    /* Now insert it in the global process list and in the process to run list */
+    xbt_swag_insert(process, simix_global->process_list);
+    DEBUG2("Inserting %s(%s) in the to_run list", process->name, host->name);
+    xbt_swag_insert(process, simix_global->process_to_run);
+  }
 
+  return process;
+}
 
-/** \brief Kill a SIMIX process
+/**
+ * \brief Internal function to kill a SIMIX process.
  *
- * This function simply kills a \a process... scarry isn't it ? :).
- * \param process poor victim
+ * This function may be called when a REQ_PROCESS_KILL request occurs,
+ * or directly for SIMIX internal purposes.
  *
+ * \param process poor victim
  */
-void SIMIX_process_kill(smx_process_t process)
-{
-  smx_simdata_process_t p_simdata = process->simdata;
+void SIMIX_process_kill(smx_process_t process, smx_process_t killer) {
 
-  DEBUG2("Killing process %s on %s", process->name,
-        p_simdata->smx_host->name);
+  DEBUG2("Killing process %s on %s", process->name, process->smx_host->name);
 
-  /* Cleanup if we were waiting for something */
-  if (p_simdata->mutex)
-    xbt_swag_remove(process, p_simdata->mutex->sleeping);
+  process->context->iwannadie = 1;
+  process->blocked = 0;
+  process->suspended = 0;
+  /* FIXME: set doexception to 0 also? */
 
-  if (p_simdata->cond)
-    xbt_swag_remove(process, p_simdata->cond->sleeping);
+  if (process->waiting_action) {
 
-  xbt_swag_remove(process, simix_global->process_to_run);
-  xbt_swag_remove(process, simix_global->process_list);
-  DEBUG2("%p here! killing %p", simix_global->current_process, process);
-  xbt_context_kill(process->simdata->context);
+    switch (process->waiting_action->type) {
+
+      case SIMIX_ACTION_EXECUTE:          
+      case SIMIX_ACTION_PARALLEL_EXECUTE:
+        SIMIX_host_execution_destroy(process->waiting_action);
+        break;
+
+      case SIMIX_ACTION_COMMUNICATE:
+        SIMIX_comm_destroy(process->waiting_action);
+        break;
+
+      case SIMIX_ACTION_SLEEP:
+       SIMIX_process_sleep_destroy(process->waiting_action);
+       break;
 
-  if (process == SIMIX_process_self()) {
-    /* I just killed myself */
-    xbt_context_yield();
+      case SIMIX_ACTION_SYNCHRO:
+       SIMIX_synchro_stop_waiting(process, process->request);
+       SIMIX_synchro_destroy(process->waiting_action);
+       break;
+
+      case SIMIX_ACTION_IO:
+       THROW_UNIMPLEMENTED;
+       break;
+    }
+  }
+
+  /* If I'm killing myself then stop, otherwise schedule the process to kill. */
+  if (process == killer) {
+    SIMIX_context_stop(process->context);
+  }
+  else {
+    xbt_swag_insert(process, simix_global->process_to_run);
   }
 }
 
 /**
- * \brief Return the user data of a #smx_process_t.
+ * \brief Kills all running processes.
  *
- * This functions checks whether \a process is a valid pointer or not and return the user data associated to \a process if it is possible.
- * \param process SIMIX process
- * \return A void pointer to the user data
+ * Only maestro can kill everyone.
  */
-void *SIMIX_process_get_data(smx_process_t process)
+void SIMIX_process_killall(void)
+{
+  smx_process_t p = NULL;
+
+  while ((p = xbt_swag_extract(simix_global->process_list)))
+    SIMIX_process_kill(p, SIMIX_process_self());
+
+  SIMIX_process_empty_trash();
+}
+
+void SIMIX_process_change_host(smx_process_t process,
+    const char *source, const char *dest)
 {
+  smx_host_t h1 = NULL;
+  smx_host_t h2 = NULL;
   xbt_assert0((process != NULL), "Invalid parameters");
+  h1 = SIMIX_host_get_by_name(source);
+  h2 = SIMIX_host_get_by_name(dest);
+  process->smx_host = h2;
+  xbt_swag_remove(process, h1->process_list);
+  xbt_swag_insert(process, h2->process_list);
+}
+
+void SIMIX_pre_process_suspend(smx_req_t req)
+{
+  smx_process_t process = req->process_suspend.process;
+  SIMIX_process_suspend(process, req->issuer);
 
-  return (process->data);
+  if (process != req->issuer) {
+    SIMIX_request_answer(req);
+  }
+  /* If we are suspending ourselves, then just do not replay the request. */
 }
 
-/**
- * \brief Set the user data of a #m_process_t.
- *
- * This functions checks whether \a process is a valid pointer or not and set the user data associated to \a process if it is possible.
- * \param process SIMIX process
- * \param data User data
- */
-void SIMIX_process_set_data(smx_process_t process, void *data)
+void SIMIX_process_suspend(smx_process_t process, smx_process_t issuer)
+{
+  xbt_assert0(process, "Invalid parameters");
+
+  process->suspended = 1;
+
+  /* If we are suspending another process, and it is waiting on an action,
+     suspend it's action. */
+  if (process != issuer) {
+
+    if (process->waiting_action) {
+
+      switch (process->waiting_action->type) {
+
+        case SIMIX_ACTION_EXECUTE:
+        case SIMIX_ACTION_PARALLEL_EXECUTE:
+          SIMIX_host_execution_suspend(process->waiting_action);
+          break;
+
+        case SIMIX_ACTION_COMMUNICATE:
+          SIMIX_comm_suspend(process->waiting_action);
+          break;
+
+        case SIMIX_ACTION_SLEEP:
+          SIMIX_process_sleep_suspend(process->waiting_action);
+          break;
+
+        default:
+          THROW_IMPOSSIBLE;
+      }
+    }
+  }
+}
+
+void SIMIX_process_resume(smx_process_t process, smx_process_t issuer)
 {
   xbt_assert0((process != NULL), "Invalid parameters");
-  //xbt_assert0((process->data == NULL), "Data already set");
 
-  process->data = data;
+  process->suspended = 0;
 
-  return;
+  /* If we are resuming another process, resume the action it was waiting for
+     if any. Otherwise add it to the list of process to run in the next round. */
+  if (process != issuer) {
+
+    if (process->waiting_action) {
+
+      switch (process->waiting_action->type) {
+
+        case SIMIX_ACTION_EXECUTE:          
+        case SIMIX_ACTION_PARALLEL_EXECUTE:
+          SIMIX_host_execution_resume(process->waiting_action);
+          break;
+
+        case SIMIX_ACTION_COMMUNICATE:
+          SIMIX_comm_resume(process->waiting_action);
+          break;
+
+        case SIMIX_ACTION_SLEEP:
+          SIMIX_process_sleep_resume(process->waiting_action);
+          break;
+
+        default:
+          THROW_IMPOSSIBLE;
+      }
+    }
+    else {
+      xbt_swag_insert(process, simix_global->process_to_run);
+    }
+  }
 }
 
-/**
- * \brief Return the location on which an agent is running.
- *
- * This functions checks whether \a process is a valid pointer or not and return the m_host_t corresponding to the location on which \a process is running.
- * \param process SIMIX process
- * \return SIMIX host
- */
-smx_host_t SIMIX_process_get_host(smx_process_t process)
+int SIMIX_process_count(void)
 {
-  xbt_assert0(((process != NULL)
-              && (process->simdata)), "Invalid parameters");
+  return xbt_swag_size(simix_global->process_list);
+}
 
-  return (process->simdata->smx_host);
+void* SIMIX_process_self_get_data(void)
+{
+  smx_process_t me = SIMIX_process_self();
+  if (!me) {
+    return NULL;
+  }
+  return SIMIX_process_get_data(me);
 }
 
-/**
- * \brief Return the name of an agent.
- *
- * This functions checks whether \a process is a valid pointer or not and return its name.
- * \param process SIMIX process
- * \return The process name
- */
-const char *SIMIX_process_get_name(smx_process_t process)
+void SIMIX_process_self_set_data(void *data)
 {
-  xbt_assert0(((process != NULL)
-              && (process->simdata)), "Invalid parameters");
+  SIMIX_process_set_data(SIMIX_process_self(), data);
+}
 
-  return (process->name);
+void* SIMIX_process_get_data(smx_process_t process)
+{
+  return process->data;
 }
 
-/** \ingroup m_process_management
- * \brief Return the properties
- *
- * This functions returns the properties associated with this process
- */
-xbt_dict_t SIMIX_process_get_properties(smx_process_t process)
+void SIMIX_process_set_data(smx_process_t process, void *data)
 {
-  return process->simdata->properties;
+  process->data = data;
 }
 
-/**
- * \brief Return the current agent.
- *
- * This functions returns the currently running #smx_process_t.
- * \return The SIMIX process
- */
-smx_process_t SIMIX_process_self(void)
+smx_host_t SIMIX_process_get_host(smx_process_t process)
 {
-  return simix_global ? simix_global->current_process : NULL;
+  return process->smx_host;
 }
 
-/**
- * \brief Suspend the process.
- *
- * This functions suspend the process by suspending the action on
- * which it was waiting for the completion.
- *
- * \param process SIMIX process
- */
-void SIMIX_process_suspend(smx_process_t process)
+/* needs to be public and without request because it is called
+   by exceptions and logging events */
+const char* SIMIX_process_self_get_name(void) {
+
+  smx_process_t process = SIMIX_process_self();
+  if (process == NULL || process == simix_global->maestro_process)
+    return "";
+
+  return SIMIX_process_get_name(process);
+}
+
+const char* SIMIX_process_get_name(smx_process_t process)
 {
-  smx_simdata_process_t simdata = NULL;
+  return process->name;
+}
 
-  xbt_assert0(((process) && (process->simdata)), "Invalid parameters");
+int SIMIX_process_is_suspended(smx_process_t process)
+{
+  return process->suspended;
+}
 
-  if (process != SIMIX_process_self()) {
-    simdata = process->simdata;
+int SIMIX_process_is_enabled(smx_process_t process)
+{
+  if (process->request && SIMIX_request_is_enabled(process->request))
+    return TRUE;
 
-    if (simdata->mutex) {
-      /* process blocked on a mutex, only set suspend=1 */
-      simdata->suspended = 1;
-    } else if (simdata->cond) {
-      /* process blocked cond, suspend all actions */
+  return FALSE;
+}
 
-      /* temporaries variables */
-      smx_cond_t c;
-      xbt_fifo_item_t i;
-      smx_action_t act;
+xbt_dict_t SIMIX_process_get_properties(smx_process_t process)
+{
+  return process->properties;
+}
 
-      simdata->suspended = 1;
-      c = simdata->cond;
-      xbt_fifo_foreach(c->actions, i, act, smx_action_t) {
-       surf_workstation_model->common_public->suspend(act->simdata->
-                                                         surf_action);
-      }
-    } else {
-      simdata->suspended = 1;
-    }
-  } else {
-    /* process executing, I can create an action and suspend it */
-    smx_action_t dummy;
-    smx_cond_t cond;
-    char name[] = "dummy";
-    process->simdata->suspended = 1;
-
-    cond = SIMIX_cond_init();
-    dummy = SIMIX_action_execute(SIMIX_process_get_host(process), name, 0);
-    surf_workstation_model->common_public->suspend(dummy->simdata->surf_action);
-    SIMIX_register_action_to_condition(dummy, cond);
-    __SIMIX_cond_wait(cond);
-    SIMIX_unregister_action_to_condition(dummy, cond);
-    SIMIX_action_destroy(dummy);
-    SIMIX_cond_destroy(cond);
+void SIMIX_pre_process_sleep(smx_req_t req)
+{
+  if (MC_IS_ENABLED) {
+    req->process_sleep.result = SIMIX_DONE;
+    SIMIX_request_answer(req);
   }
-  return;
+  smx_action_t action = SIMIX_process_sleep(req->issuer, req->process_sleep.duration);
+  xbt_fifo_push(action->request_list, req);
+  req->issuer->waiting_action = action;
 }
 
-/**
- * \brief Resume a suspended process.
- *
- * This functions resume a suspended process by resuming the task on which it was waiting for the completion.
- * \param process SIMIX process
- */
-void SIMIX_process_resume(smx_process_t process)
+smx_action_t SIMIX_process_sleep(smx_process_t process, double duration)
 {
-  smx_simdata_process_t simdata = NULL;
+  smx_action_t action;
+  smx_host_t host = process->smx_host;
+
+  /* check if the host is active */
+  if (surf_workstation_model->extension.
+      workstation.get_state(host->host) != SURF_RESOURCE_ON) {
+    THROW1(host_error, 0, "Host %s failed, you cannot call this function",
+           host->name);
+  }
 
-  xbt_assert0(((process != NULL)
-              && (process->simdata)), "Invalid parameters");
-  SIMIX_CHECK_HOST();
+  action = xbt_new0(s_smx_action_t, 1);
+  action->type = SIMIX_ACTION_SLEEP;
+  action->request_list = xbt_fifo_new();
+  action->name = xbt_strdup("sleep");
+#ifdef HAVE_TRACING
+  action->category = NULL;
+#endif
 
-  if (process == SIMIX_process_self()) {
-    return;
-  }
+  action->sleep.host = host;
+  action->sleep.surf_sleep =
+      surf_workstation_model->extension.workstation.sleep(host->host, duration);
 
-  simdata = process->simdata;
-  if (simdata->mutex) {
-    DEBUG0("Resume process blocked on a mutex");
-    simdata->suspended = 0;    /* He'll wake up by itself */
-    return;
-  } else if (simdata->cond) {
-    /* temporaries variables */
-    smx_cond_t c;
-    xbt_fifo_item_t i;
-    smx_action_t act;
-       DEBUG0("Resume process blocked on a conditional");
-    simdata->suspended = 0;
-    c = simdata->cond;
-    xbt_fifo_foreach(c->actions, i, act, smx_action_t) {
-      surf_workstation_model->common_public->resume(act->simdata->surf_action);
-    }
-    SIMIX_cond_signal(c);
-    return;
-  } else {
-    simdata->suspended = 0;
-    xbt_swag_insert(process, simix_global->process_to_run);
+  surf_workstation_model->action_data_set(action->sleep.surf_sleep, action);
+  DEBUG1("Create sleep action %p", action);
+
+  return action;
+}
+
+void SIMIX_post_process_sleep(smx_action_t action)
+{
+  e_smx_state_t state = SIMIX_action_map_state(surf_workstation_model->action_state_get(action->sleep.surf_sleep));
+  smx_req_t req;
+
+  while ((req = xbt_fifo_shift(action->request_list))) {
+    req->process_sleep.result = state;
+    req->issuer->waiting_action = NULL;
+    SIMIX_request_answer(req);
   }
 
+  SIMIX_process_sleep_destroy(action);
 }
 
-/**
- * \brief Migrates an agent to another location.
- *
- * This function changes the value of the host on which \a process is running.
- */
-void SIMIX_process_change_host(smx_process_t process, char *source, char *dest)
+void SIMIX_process_sleep_destroy(smx_action_t action)
 {
-  smx_simdata_process_t p_simdata = process->simdata;
-  smx_host_t h1 = SIMIX_host_get_by_name(source);
-  smx_host_t h2 = SIMIX_host_get_by_name(dest);
-  p_simdata->smx_host =  h2;
-  xbt_swag_remove(process, h1->simdata->process_list);
-  xbt_swag_insert(process, h2->simdata->process_list);
+  DEBUG1("Destroy action %p", action);
+  if (action->name)
+    xbt_free(action->name);
+  if (action->sleep.surf_sleep)
+    action->sleep.surf_sleep->model_type->action_unref(action->sleep.surf_sleep);
+#ifdef HAVE_TRACING
+  TRACE_smx_action_destroy(action);
+#endif
+  xbt_fifo_free(action->request_list);
+  xbt_free(action);
 }
 
-/**
- * \brief Returns true if the process is suspended .
- *
- * This checks whether a process is suspended or not by inspecting the task on which it was waiting for the completion.
- * \param process SIMIX process
- * \return 1, if the process is suspended, else 0.
+void SIMIX_process_sleep_suspend(smx_action_t action)
+{
+  surf_workstation_model->suspend(action->sleep.surf_sleep);
+}
+
+void SIMIX_process_sleep_resume(smx_action_t action)
+{
+  surf_workstation_model->resume(action->sleep.surf_sleep);
+}
+
+/** 
+ * Calling this function makes the process to yield.
+ * Only the processes can call this function, giving back the control to maestro
  */
-int SIMIX_process_is_suspended(smx_process_t process)
+void SIMIX_process_yield(void)
 {
-  xbt_assert0(((process != NULL)
-              && (process->simdata)), "Invalid parameters");
+  smx_process_t self = SIMIX_process_self();
+
+  DEBUG1("Yield process '%s'", self->name);
 
-  return (process->simdata->suspended);
+  /* Go into sleep and return control to maestro */
+  SIMIX_context_suspend(self->context);
+
+  /* Ok, maestro returned control to us */
+  DEBUG1("Maestro returned control to me: '%s'", self->name);
+
+  if (self->context->iwannadie)
+    SIMIX_context_stop(self->context);
+
+  if (self->doexception) {
+    DEBUG0("Wait, maestro left me an exception");
+    self->doexception = 0;
+    RETHROW;
+  }
 }
 
+/* callback: context fetching */
+xbt_running_ctx_t *SIMIX_process_get_running_context(void)
+{
+  return SIMIX_process_self()->running_ctx;
+}
 
+/* callback: termination */
+void SIMIX_process_exception_terminate(xbt_ex_t * e)
+{
+  xbt_ex_display(e);
+  abort();
+}
+
+smx_context_t SIMIX_process_get_context(smx_process_t p) {
+  return p->context;
+}
+void SIMIX_process_set_context(smx_process_t p,smx_context_t c) {
+  p->context = c;
+}