+++ /dev/null
-/* Copyright (c) 2010-2021. 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. */
-
-/***************** Centralized Mutual Exclusion Algorithm *********************/
-/* This example implements a centralized mutual exclusion algorithm. */
-/* There is no bug on it, it is just provided to test the state space */
-/* reduction of DPOR. */
-/******************************************************************************/
-
-#include "simgrid/msg.h"
-
-#define AMOUNT_OF_CLIENTS 4
-#define CS_PER_PROCESS 2
-XBT_LOG_NEW_DEFAULT_CATEGORY(centralized, "my log messages");
-
-static int coordinator(XBT_ATTRIB_UNUSED int argc, XBT_ATTRIB_UNUSED char* argv[])
-{
- xbt_dynar_t requests = xbt_dynar_new(sizeof(char *), NULL); // dynamic vector storing requests (which are char*)
- int CS_used = 0; // initially the CS is idle
- int todo = AMOUNT_OF_CLIENTS * CS_PER_PROCESS; // amount of releases we are expecting
- while (todo > 0) {
- msg_task_t task = NULL;
- MSG_task_receive(&task, "coordinator");
- const char *kind = MSG_task_get_name(task); //is it a request or a release?
- if (!strcmp(kind, "request")) { // that's a request
- char *req = MSG_task_get_data(task);
- if (CS_used) { // need to push the request in the vector
- XBT_INFO("CS already used. Queue the request");
- xbt_dynar_push(requests, &req);
- } else { // can serve it immediately
- XBT_INFO("CS idle. Grant immediately");
- msg_task_t answer = MSG_task_create("grant", 0, 1000, NULL);
- MSG_task_send(answer, req);
- CS_used = 1;
- }
- } else { // that's a release. Check if someone was waiting for the lock
- if (!xbt_dynar_is_empty(requests)) {
- XBT_INFO("CS release. Grant to queued requests (queue size: %lu)", xbt_dynar_length(requests));
- char *req;
- xbt_dynar_shift(requests, &req);
- MSG_task_send(MSG_task_create("grant", 0, 1000, NULL), req);
- todo--;
- } else { // nobody wants it
- XBT_INFO("CS release. resource now idle");
- CS_used = 0;
- todo--;
- }
- }
- MSG_task_destroy(task);
- }
- XBT_INFO("Received all releases, quit now");
- return 0;
-}
-
-static int client(XBT_ATTRIB_UNUSED int argc, XBT_ATTRIB_UNUSED char* argv[])
-{
- int my_pid = MSG_process_get_PID(MSG_process_self());
- // use my pid as name of mailbox to contact me
- char *my_mailbox = bprintf("%d", my_pid);
- // request the CS 3 times, sleeping a bit in between
- int i;
- for (i = 0; i < CS_PER_PROCESS; i++) {
- XBT_INFO("Ask the request");
- MSG_task_send(MSG_task_create("request", 0, 1000, my_mailbox), "coordinator");
- // wait the answer
- msg_task_t grant = NULL;
- MSG_task_receive(&grant, my_mailbox);
- MSG_task_destroy(grant);
- XBT_INFO("got the answer. Sleep a bit and release it");
- MSG_process_sleep(1);
- MSG_task_send(MSG_task_create("release", 0, 1000, NULL), "coordinator");
- MSG_process_sleep(my_pid);
- }
- XBT_INFO("Got all the CS I wanted, quit now");
- return 0;
-}
-
-int main(int argc, char *argv[])
-{
- MSG_init(&argc, argv);
- MSG_create_environment(argv[1]);
- MSG_function_register("coordinator", coordinator);
- MSG_function_register("client", client);
- MSG_launch_application("deploy_centralized_mutex.xml");
- MSG_main();
- return 0;
-}
