-/* Copyright (c) 2009-2015. The SimGrid Team.
- * All rights reserved. */
+/* Copyright (c) 2009-2016. 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 "simgrid/msg.h"
#include "xbt/synchro_core.h"
-XBT_LOG_NEW_DEFAULT_CATEGORY(msg_test, "Messages specific for this msg example");
+XBT_LOG_NEW_DEFAULT_CATEGORY(msg_process_migration, "Messages specific for this msg example");
-/** @addtogroup MSG_examples
- *
- * - <b>migration/migration.c</b> Demonstrates how to use the @ref MSG_process_migrate function to let processes
- * change the host they run on after their start.
- */
+xbt_mutex_t checkpoint = NULL;
+xbt_cond_t identification = NULL;
+static msg_process_t controlled_process = NULL;
-xbt_mutex_t mutex = NULL;
-xbt_cond_t cond = NULL;
-static msg_process_t process_to_migrate = NULL;
-
-/** The guy we will move from host to host. It move alone and then is moved by policeman back */
+/* The Emigrant process will be moved from host to host. */
static int emigrant(int argc, char *argv[])
{
- msg_task_t task;
- XBT_INFO("I'll look for a new job on another machine where the grass is greener.");
- MSG_process_migrate(MSG_process_self(), MSG_host_by_name("Boivin"));
+ XBT_INFO("I'll look for a new job on another machine ('Boivin') where the grass is greener.");
+ MSG_process_migrate(MSG_process_self(), MSG_host_by_name("Boivin")); /* - First, move to another host by myself */
XBT_INFO("Yeah, found something to do");
- task = MSG_task_create("job", 98095000, 0, NULL);
+ msg_task_t task = MSG_task_create("job", 98095000, 0, NULL); /* - Execute some work there */
MSG_task_execute(task);
MSG_task_destroy(task);
MSG_process_sleep(2);
XBT_INFO("Moving back home after work");
- MSG_process_migrate(MSG_process_self(), MSG_host_by_name("Jacquelin"));
- MSG_process_migrate(MSG_process_self(), MSG_host_by_name("Boivin"));
+ MSG_process_migrate(MSG_process_self(), MSG_host_by_name("Jacquelin")); /* - Move back to original location */
+ MSG_process_migrate(MSG_process_self(), MSG_host_by_name("Boivin")); /* - Go back to the other host to sleep*/
MSG_process_sleep(4);
- xbt_mutex_acquire(mutex);
- process_to_migrate = MSG_process_self();
- xbt_cond_broadcast(cond);
- xbt_mutex_release(mutex);
+ xbt_mutex_acquire(checkpoint); /* - Get controlled at checkpoint */
+ controlled_process = MSG_process_self(); /* - and get moved back by the policeman process */
+ xbt_cond_broadcast(identification);
+ xbt_mutex_release(checkpoint);
MSG_process_suspend(MSG_process_self());
msg_host_t h = MSG_process_get_host(MSG_process_self());
XBT_INFO("I've been moved on this new host: %s", MSG_host_get_name(h));
return 0;
}
-/* This function move the emigrant on Jacquelin */
+/* The policeman check for emigrants and move them back to 'Jacquelin' */
static int policeman(int argc, char *argv[])
{
- xbt_mutex_acquire(mutex);
- XBT_INFO("Wait a bit before migrating the emigrant.");
- while (process_to_migrate == NULL) xbt_cond_wait(cond, mutex);
- MSG_process_migrate(process_to_migrate, MSG_host_by_name("Jacquelin"));
+ xbt_mutex_acquire(checkpoint);
+ XBT_INFO("Wait at the checkpoint."); /* - block on the mutex+condition */
+ while (controlled_process == NULL) xbt_cond_wait(identification, checkpoint);
+ MSG_process_migrate(controlled_process, MSG_host_by_name("Jacquelin")); /* - Move an emigrant to Jacquelin */
XBT_INFO("I moved the emigrant");
- MSG_process_resume(process_to_migrate);
- xbt_mutex_release(mutex);
+ MSG_process_resume(controlled_process);
+ xbt_mutex_release(checkpoint);
return 0;
}
MSG_init(&argc, argv);
xbt_assert(argc == 2, "Usage: %s platform_file\n\tExample: %s msg_platform.xml\n", argv[0], argv[0]);
- MSG_create_environment(argv[1]);
-
+ MSG_create_environment(argv[1]); /* - Load the platform description */
+ /* - Create and deploy the emigrant and policeman processes */
MSG_process_create("emigrant", emigrant, NULL, MSG_get_host_by_name("Jacquelin"));
MSG_process_create("policeman", policeman, NULL, MSG_get_host_by_name("Boivin"));
- mutex = xbt_mutex_init();
- cond = xbt_cond_init();
- res = MSG_main();
+ checkpoint = xbt_mutex_init(); /* - Initiate the mutex and conditions */
+ identification = xbt_cond_init();
+ res = MSG_main(); /* - Run the simulation */
XBT_INFO("Simulation time %g", MSG_get_clock());
- xbt_cond_destroy(cond);
- xbt_mutex_destroy(mutex);
+ xbt_cond_destroy(identification);
+ xbt_mutex_destroy(checkpoint);
return res != MSG_OK;
}
