extern long int smx_total_comms;
-/**
+/*
* Finger element.
*/
typedef struct s_finger {
char mailbox[MAILBOX_NAME_SIZE]; // string representation of the id
} s_finger_t, *finger_t;
-/**
+/*
* Node data.
*/
typedef struct s_node {
TASK_PREDECESSOR_LEAVING
} e_task_type_t;
-/**
+/*
* Data attached with the tasks sent and received
*/
typedef struct s_task_data {
static void fix_fingers(node_t node);
static void check_predecessor(node_t node);
static void random_lookup(node_t);
-static void quit_notify(node_t node, int to);
+static void quit_notify(node_t node);
/**
* \brief Global initialization of the Chord simulation.
static void task_free(void* task)
{
// TODO add a parameter data_free_function to MSG_task_create?
- xbt_free(MSG_task_get_data(task));
- MSG_task_destroy(task);
+ if(task != NULL){
+ xbt_free(MSG_task_get_data(task));
+ MSG_task_destroy(task);
+ }
}
/**
*/
int node(int argc, char *argv[])
{
+
/* Reduce the run size for the MC */
- if(MC_IS_ENABLED){
+ if(MC_is_active()){
periodic_stabilize_delay = 8;
periodic_fix_fingers_delay = 8;
periodic_check_predecessor_delay = 8;
if (!MSG_comm_test(node.comm_receive)) {
// no task was received: make some periodic calls
- if (MSG_get_clock() >= next_stabilize_date) {
- stabilize(&node);
- next_stabilize_date = MSG_get_clock() + periodic_stabilize_delay;
- }
- else if (MSG_get_clock() >= next_fix_fingers_date) {
- fix_fingers(&node);
- next_fix_fingers_date = MSG_get_clock() + periodic_fix_fingers_delay;
- }
- else if (MSG_get_clock() >= next_check_predecessor_date) {
- check_predecessor(&node);
- next_check_predecessor_date = MSG_get_clock() + periodic_check_predecessor_delay;
- }
- else if (MSG_get_clock() >= next_lookup_date) {
- random_lookup(&node);
- next_lookup_date = MSG_get_clock() + periodic_lookup_delay;
- }
- else {
- // nothing to do: sleep for a while
- MSG_process_sleep(5);
- }
- }
- if (node.comm_receive && MSG_comm_test(node.comm_receive)) {
-
- // a transfer has occured
+ #ifdef HAVE_MC
+ if(MC_is_active()){
+ if(MC_random()){
+ stabilize(&node);
+ }else if(MC_random()){
+ fix_fingers(&node);
+ }else if(MC_random()){
+ check_predecessor(&node);
+ }else if(MC_random()){
+ random_lookup(&node);
+ }else{
+ MSG_process_sleep(5);
+ }
+ }else{
+ if (MSG_get_clock() >= next_stabilize_date) {
+ stabilize(&node);
+ next_stabilize_date = MSG_get_clock() + periodic_stabilize_delay;
+ }
+ else if (MSG_get_clock() >= next_fix_fingers_date) {
+ fix_fingers(&node);
+ next_fix_fingers_date = MSG_get_clock() + periodic_fix_fingers_delay;
+ }
+ else if (MSG_get_clock() >= next_check_predecessor_date) {
+ check_predecessor(&node);
+ next_check_predecessor_date = MSG_get_clock() + periodic_check_predecessor_delay;
+ }
+ else if (MSG_get_clock() >= next_lookup_date) {
+ random_lookup(&node);
+ next_lookup_date = MSG_get_clock() + periodic_lookup_delay;
+ }
+ else {
+ // nothing to do: sleep for a while
+ MSG_process_sleep(5);
+ }
+ }
+ #else
+ if (MSG_get_clock() >= next_stabilize_date) {
+ stabilize(&node);
+ next_stabilize_date = MSG_get_clock() + periodic_stabilize_delay;
+ }
+ else if (MSG_get_clock() >= next_fix_fingers_date) {
+ fix_fingers(&node);
+ next_fix_fingers_date = MSG_get_clock() + periodic_fix_fingers_delay;
+ }
+ else if (MSG_get_clock() >= next_check_predecessor_date) {
+ check_predecessor(&node);
+ next_check_predecessor_date = MSG_get_clock() + periodic_check_predecessor_delay;
+ }
+ else if (MSG_get_clock() >= next_lookup_date) {
+ random_lookup(&node);
+ next_lookup_date = MSG_get_clock() + periodic_lookup_delay;
+ }
+ else {
+ // nothing to do: sleep for a while
+ MSG_process_sleep(5);
+ }
+ #endif
+
+ } else {
+ // a transfer has occurred
msg_error_t status = MSG_comm_get_status(node.comm_receive);
static void leave(node_t node)
{
XBT_DEBUG("Well Guys! I Think it's time for me to quit ;)");
- quit_notify(node, 1); // notify to my successor ( >>> 1 );
- quit_notify(node, -1); // notify my predecessor ( >>> -1);
- // TODO ...
+ quit_notify(node);
}
/*
- * \brief Notifies the successor or the predecessor of the current node
+ * \brief Notifies the successor and the predecessor of the current node
* of the departure
* \param node the current node
- * \param to 1 to notify the successor, -1 to notify the predecessor
- * FIXME: notify both nodes with only one call
*/
-static void quit_notify(node_t node, int to)
+static void quit_notify(node_t node)
{
- /* TODO
- task_data_t req_data = xbt_new0(s_task_data_t, 1);
- req_data->request_id = node->id;
- req_data->successor_id = node->fingers[0].id;
- req_data->pred_id = node->pred_id;
+ char mailbox[MAILBOX_NAME_SIZE];
+ //send the PREDECESSOR_LEAVING to our successor
+ task_data_t req_data = xbt_new0(s_task_data_t,1);
+ req_data->type = TASK_PREDECESSOR_LEAVING;
+ req_data->request_id = node->pred_id;
+ get_mailbox(node->id, req_data->answer_to);
req_data->issuer_host_name = MSG_host_get_name(MSG_host_self());
- req_data->answer_to = NULL;
- const char* task_name = NULL;
- const char* to_mailbox = NULL;
- if (to == 1) { // notify my successor
- to_mailbox = node->fingers[0].mailbox;
- XBT_INFO("Telling my Successor %d about my departure via mailbox %s",
- node->fingers[0].id, to_mailbox);
- req_data->type = TASK_PREDECESSOR_LEAVING;
- }
- else if (to == -1) { // notify my predecessor
- if (node->pred_id == -1) {
- return;
- }
+ msg_task_t task_sent = MSG_task_create(NULL, COMP_SIZE, COMM_SIZE, req_data);
+ XBT_DEBUG("Sending a 'PREDECESSOR_LEAVING' to my successor %d",node->fingers[0].id);
+ MSG_task_send_with_timeout(task_sent, node->fingers[0].mailbox, timeout);
+
+ //send the SUCCESSOR_LEAVING to our predecessor
+ get_mailbox(node->pred_id, mailbox);
+ task_data_t req_data_s = xbt_new0(s_task_data_t,1);
+ req_data_s->type = TASK_SUCCESSOR_LEAVING;
+ req_data_s->request_id = node->fingers[0].id;
+ req_data_s->request_id = node->pred_id;
+ get_mailbox(node->id, req_data_s->answer_to);
+ req_data_s->issuer_host_name = MSG_host_get_name(MSG_host_self());
+
+ msg_task_t task_sent_s = MSG_task_create(NULL, COMP_SIZE, COMM_SIZE, req_data_s);
+ XBT_DEBUG("Sending a 'SUCCESSOR_LEAVING' to my predecessor %d",node->pred_id);
+ MSG_task_send_with_timeout(task_sent_s, mailbox, timeout);
- to_mailbox = node->pred_mailbox;
- XBT_INFO("Telling my Predecessor %d about my departure via mailbox %s",
- node->pred_id, to_mailbox);
- req_data->type = TASK_SUCCESSOR_LEAVING;
- }
- msg_task_t task = MSG_task_create(NULL, COMP_SIZE, COMM_SIZE, req_data);
- //char* mailbox = get_mailbox(to_mailbox);
- msg_comm_t comm = MSG_task_isend(task, to_mailbox);
- xbt_dynar_push(node->comms, &comm);
- */
}
/**
XBT_DEBUG("Received a task (%p)", task_received);
task_data_t ans_data = MSG_task_get_data(task_received);
- if (MC_IS_ENABLED) {
- MC_assert(task_received == task_sent);
- }
+ // Once upon a time, our code assumed that here, task_received != task_sent all the time
+ //
+ // This assumption is wrong (as messages from differing round can interleave), leading to a bug in our code.
+ // We failed to find this bug directly, as it only occured on large platforms, leading to hardly usable traces.
+ // Instead, we used the model-checker to track down the issue by adding the following test here in the code:
+ // if (MC_is_active()) {
+ // MC_assert(task_received == task_sent);
+ // }
+ // That explained the bug in a snap, with a very cool example and everything.
+ //
+ // This MC_assert is now desactivated as the case is now properly handled in our code and we don't want the
+ // MC to fail any further under that condition, but this comment is here to as a memorial for this first
+ // brillant victory of the model-checking in the SimGrid community :)
if (task_received != task_sent) {
// this is not the expected answer
msg_task_t task_received = MSG_comm_get_task(node->comm_receive);
task_data_t ans_data = MSG_task_get_data(task_received);
- if (MC_IS_ENABLED) {
+ if (MC_is_active()) {
MC_assert(task_received == task_sent);
}
*/
static void remote_notify(node_t node, int notify_id, int predecessor_candidate_id) {
- task_data_t req_data = xbt_new0(s_task_data_t, 1);
- req_data->type = TASK_NOTIFY;
- req_data->request_id = predecessor_candidate_id;
- req_data->issuer_host_name = MSG_host_get_name(MSG_host_self());
-
- // send a "Notify" request to notify_id
- msg_task_t task = MSG_task_create(NULL, COMP_SIZE, COMM_SIZE, req_data);
- XBT_DEBUG("Sending a 'Notify' request (task %p) to %d", task, notify_id);
- char mailbox[MAILBOX_NAME_SIZE];
- get_mailbox(notify_id, mailbox);
- MSG_task_dsend(task, mailbox, task_free);
-}
+ task_data_t req_data = xbt_new0(s_task_data_t, 1);
+ req_data->type = TASK_NOTIFY;
+ req_data->request_id = predecessor_candidate_id;
+ req_data->issuer_host_name = MSG_host_get_name(MSG_host_self());
+
+ // send a "Notify" request to notify_id
+ msg_task_t task = MSG_task_create(NULL, COMP_SIZE, COMM_SIZE, req_data);
+ XBT_DEBUG("Sending a 'Notify' request (task %p) to %d", task, notify_id);
+ char mailbox[MAILBOX_NAME_SIZE];
+ get_mailbox(notify_id, mailbox);
+ MSG_task_dsend(task, mailbox, task_free);
+ }
/**
* \brief This function is called periodically.
XBT_CRITICAL("Messages created: %ld", smx_total_comms);
XBT_INFO("Simulated time: %g", MSG_get_clock());
- MSG_clean();
chord_exit();
if (res == MSG_OK)