#include "msg/msg.h"
#include "xbt/log.h"
#include "xbt/asserts.h"
+#include "mc/modelchecker.h"
+#include "mc/mc.h"
XBT_LOG_NEW_DEFAULT_CATEGORY(msg_chord,
"Messages specific for this msg example");
#define COMM_SIZE 10
#define COMP_SIZE 0
+#define MAILBOX_NAME_SIZE 10
-static int nb_bits = 16;
+static int nb_bits = 24;
static int nb_keys = 0;
static int timeout = 50;
+static int max_simulation_time = 1000;
+static int periodic_stabilize_delay = 20;
+static int periodic_fix_fingers_delay = 120;
+static int periodic_check_predecessor_delay = 120;
+static int periodic_lookup_delay = 10;
/**
* Finger element.
*/
typedef struct finger {
int id;
- char* mailbox;
+ char mailbox[MAILBOX_NAME_SIZE]; // string representation of the id
} s_finger_t, *finger_t;
/**
*/
typedef struct node {
int id; // my id
- char* mailbox; // my usual mailbox name
+ char mailbox[MAILBOX_NAME_SIZE]; // my mailbox name (string representation of the id)
s_finger_t *fingers; // finger table, of size nb_bits (fingers[0] is my successor)
int pred_id; // predecessor id
- char* pred_mailbox; // predecessor's mailbox name
+ char pred_mailbox[MAILBOX_NAME_SIZE]; // predecessor's mailbox name
int next_finger_to_fix; // index of the next finger to fix in fix_fingers()
msg_comm_t comm_receive; // current communication to receive
xbt_dynar_t comms; // current communications being sent
int request_id; // id paramater (used by some types of tasks)
int request_finger; // finger parameter (used by some types of tasks)
int answer_id; // answer (used by some types of tasks)
- char* answer_to; // mailbox to send an answer to (or NULL)
+ char answer_to[MAILBOX_NAME_SIZE]; // mailbox to send an answer to (if any)
const char* issuer_host_name; // used for logging
} s_task_data_t, *task_data_t;
static void chord_initialize(void);
static int normalize(int id);
static int is_in_interval(int id, int start, int end);
-static char* get_mailbox(int host_id);
+static void get_mailbox(int host_id, char* mailbox);
static void task_data_destroy(task_data_t task_data);
static void print_finger_table(node_t node);
static void set_finger(node_t node, int finger_index, int id);
static void remote_notify(node_t node, int notify_to, int predecessor_candidate_id);
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 int normalize(int id)
{
- // make sure id >= 0
- while (id < 0) {
- id += nb_keys;
- }
- // make sure id < nb_keys
- id = id % nb_keys;
-
- return id;
+ // like id % nb_keys, but works with negatives numbers (and faster)
+ return id & (nb_keys - 1);
}
/**
/**
* \brief Gets the mailbox name of a host given its chord id.
* \param node_id id of a node
- * \return the name of its mailbox
+ * \param mailbox pointer to where the mailbox name should be written
+ * (there must be enough space)
*/
-static char* get_mailbox(int node_id)
+static void get_mailbox(int node_id, char* mailbox)
{
- return bprintf("mailbox%d", node_id);
+ snprintf(mailbox, MAILBOX_NAME_SIZE - 1, "%d", node_id);
}
/**
*/
static void task_data_destroy(task_data_t task_data)
{
- xbt_free(task_data->answer_to);
xbt_free(task_data);
}
{
if (XBT_LOG_ISENABLED(msg_chord, xbt_log_priority_verbose)) {
int i;
- int pow = 1;
VERB0("My finger table:");
VERB0("Start | Succ ");
for (i = 0; i < nb_bits; i++) {
- VERB2(" %3d | %3d ", (node->id + pow) % nb_keys, node->fingers[i].id);
- pow = pow << 1;
+ VERB2(" %3d | %3d ", (node->id + powers2[i]) % nb_keys, node->fingers[i].id);
}
VERB1("Predecessor: %d", node->pred_id);
}
{
if (id != node->fingers[finger_index].id) {
node->fingers[finger_index].id = id;
- xbt_free(node->fingers[finger_index].mailbox);
- node->fingers[finger_index].mailbox = get_mailbox(id);
+ get_mailbox(id, node->fingers[finger_index].mailbox);
node->last_change_date = MSG_get_clock();
DEBUG2("My new finger #%d is %d", finger_index, id);
}
{
if (predecessor_id != node->pred_id) {
node->pred_id = predecessor_id;
- xbt_free(node->pred_mailbox);
if (predecessor_id != -1) {
- node->pred_mailbox = get_mailbox(predecessor_id);
+ get_mailbox(predecessor_id, node->pred_mailbox);
}
node->last_change_date = MSG_get_clock();
int node(int argc, char *argv[])
{
double init_time = MSG_get_clock();
- m_task_t task = NULL;
m_task_t task_received = NULL;
msg_comm_t comm_send = NULL;
int i;
int index;
int join_success = 0;
double deadline;
- double next_stabilize_date = init_time + 10;
- double next_fix_fingers_date = init_time + 10;
- double next_check_predecessor_date = init_time + 10;
+ double next_stabilize_date = init_time + periodic_stabilize_delay;
+ double next_fix_fingers_date = init_time + periodic_fix_fingers_delay;
+ double next_check_predecessor_date = init_time + periodic_check_predecessor_delay;
+ double next_lookup_date = init_time + periodic_lookup_delay;
xbt_assert0(argc == 3 || argc == 5, "Wrong number of arguments for this node");
// initialize my node
s_node_t node = {0};
node.id = atoi(argv[1]);
- node.mailbox = get_mailbox(node.id);
+ get_mailbox(node.id, node.mailbox);
node.next_finger_to_fix = 0;
node.comms = xbt_dynar_new(sizeof(msg_comm_t), NULL);
node.fingers = xbt_new0(s_finger_t, nb_bits);
- node.last_change_date = MSG_get_clock();
+ node.last_change_date = init_time;
for (i = 0; i < nb_bits; i++) {
+ node.fingers[i].id = -1;
set_finger(&node, i, node.id);
}
}
else {
int known_id = atoi(argv[2]);
- double sleep_time = atof(argv[3]);
+ //double sleep_time = atof(argv[3]);
deadline = atof(argv[4]);
+ /*
// sleep before starting
DEBUG1("Let's sleep during %f", sleep_time);
MSG_process_sleep(sleep_time);
+ */
DEBUG0("Hey! Let's join the system.");
join_success = join(&node, known_id);
if (join_success) {
while (MSG_get_clock() < init_time + deadline
- && MSG_get_clock() < node.last_change_date + 1000) {
+// && MSG_get_clock() < node.last_change_date + 1000
+ && MSG_get_clock() < max_simulation_time) {
if (node.comm_receive == NULL) {
task_received = NULL;
// no task was received: make some periodic calls
if (MSG_get_clock() >= next_stabilize_date) {
stabilize(&node);
- next_stabilize_date = MSG_get_clock() + 8;
+ 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() + 8;
+ 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() + 8;
+ 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);
xbt_dynar_remove_at(node.comms, index, &comm_send);
DEBUG3("Communication %p is finished with status %d, dynar size is now %lu",
comm_send, status, xbt_dynar_length(node.comms));
+ m_task_t task = MSG_comm_get_task(comm_send);
MSG_comm_destroy(comm_send);
+ if (status != MSG_OK) {
+ task_data_destroy(MSG_task_get_data(task));
+ MSG_task_destroy(task);
+ }
}
}
// clean unfinished comms sent
- unsigned int cursor;
+ /* unsigned int cursor;
xbt_dynar_foreach(node.comms, cursor, comm_send) {
- task = MSG_comm_get_task(comm_send);
+ m_task_t task = MSG_comm_get_task(comm_send);
MSG_task_cancel(task);
task_data_destroy(MSG_task_get_data(task));
MSG_task_destroy(task);
MSG_comm_destroy(comm_send);
// FIXME: the task is actually not destroyed because MSG thinks that the other side (whose process is dead) is still using it
- }
+ }*/
// leave the ring
leave(&node);
// stop the simulation
xbt_dynar_free(&node.comms);
- xbt_free(node.mailbox);
- xbt_free(node.pred_mailbox);
- for (i = 0; i < nb_bits - 1; i++) {
- xbt_free(node.fingers[i].mailbox);
- }
xbt_free(node.fingers);
return 0;
}
DEBUG1("Handling task %p", task);
msg_comm_t comm = NULL;
- char* mailbox = NULL;
+ char mailbox[MAILBOX_NAME_SIZE];
task_data_t task_data = (task_data_t) MSG_task_get_data(task);
e_task_type_t type = task_data->type;
if (is_in_interval(task_data->request_id, node->id + 1, node->fingers[0].id)) {
task_data->type = TASK_FIND_SUCCESSOR_ANSWER;
task_data->answer_id = node->fingers[0].id;
- DEBUG3("Sending back a 'Find Successor Answer' to %s: the successor of %d is %d",
+ DEBUG4("Sending back a 'Find Successor Answer' to %s (mailbox %s): the successor of %d is %d",
task_data->issuer_host_name,
+ task_data->answer_to,
task_data->request_id, task_data->answer_id);
comm = MSG_task_isend(task, task_data->answer_to);
xbt_dynar_push(node->comms, &comm);
int closest = closest_preceding_node(node, task_data->request_id);
DEBUG2("Forwarding the 'Find Successor' request for id %d to my closest preceding finger %d",
task_data->request_id, closest);
- mailbox = get_mailbox(closest);
+ get_mailbox(closest, mailbox);
comm = MSG_task_isend(task, mailbox);
xbt_dynar_push(node->comms, &comm);
- xbt_free(mailbox);
}
break;
case TASK_FIND_SUCCESSOR_ANSWER:
case TASK_GET_PREDECESSOR_ANSWER:
DEBUG2("Ignoring unexpected task of type %d (%p)", type, task);
+ task_data_destroy(task_data);
+ MSG_task_destroy(task);
break;
}
}
{
int successor = -1;
int stop = 0;
- char* mailbox = get_mailbox(ask_to);
+ char mailbox[MAILBOX_NAME_SIZE];
+ get_mailbox(ask_to, mailbox);
task_data_t req_data = xbt_new0(s_task_data_t, 1);
req_data->type = TASK_FIND_SUCCESSOR;
req_data->request_id = id;
- req_data->answer_to = xbt_strdup(node->mailbox);
+ get_mailbox(node->id, req_data->answer_to);
req_data->issuer_host_name = MSG_host_get_name(MSG_host_self());
// send a "Find Successor" request to ask_to_id
DEBUG2("Failed to receive the answer to my 'Find Successor' request (task %p): %d",
task_sent, res);
stop = 1;
- //MSG_comm_destroy(node->comm_receive);
+ MSG_comm_destroy(node->comm_receive);
+ node->comm_receive = NULL;
}
else {
m_task_t task_received = MSG_comm_get_task(node->comm_receive);
DEBUG1("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);
+ }
+
if (task_received != task_sent) {
// this is not the expected answer
+ MSG_comm_destroy(node->comm_receive);
+ node->comm_receive = NULL;
handle_task(node, task_received);
}
else {
ans_data->request_id, task_received, id, ans_data->answer_id);
successor = ans_data->answer_id;
stop = 1;
+ MSG_comm_destroy(node->comm_receive);
+ node->comm_receive = NULL;
MSG_task_destroy(task_received);
task_data_destroy(req_data);
}
}
- node->comm_receive = NULL;
} while (!stop);
}
- xbt_free(mailbox);
return successor;
}
{
int predecessor_id = -1;
int stop = 0;
- char* mailbox = get_mailbox(ask_to);
+ char mailbox[MAILBOX_NAME_SIZE];
+ get_mailbox(ask_to, mailbox);
task_data_t req_data = xbt_new0(s_task_data_t, 1);
req_data->type = TASK_GET_PREDECESSOR;
- req_data->answer_to = xbt_strdup(node->mailbox);
+ get_mailbox(node->id, req_data->answer_to);
req_data->issuer_host_name = MSG_host_get_name(MSG_host_self());
// send a "Get Predecessor" request to ask_to_id
DEBUG2("Failed to receive the answer to my 'Get Predecessor' request (task %p): %d",
task_sent, res);
stop = 1;
- //MSG_comm_destroy(node->comm_receive);
+ MSG_comm_destroy(node->comm_receive);
+ node->comm_receive = NULL;
}
else {
m_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) {
+ MC_assert(task_received == task_sent);
+ }
+
if (task_received != task_sent) {
+ MSG_comm_destroy(node->comm_receive);
+ node->comm_receive = NULL;
handle_task(node, task_received);
}
else {
task_received, ask_to, ans_data->answer_id);
predecessor_id = ans_data->answer_id;
stop = 1;
+ MSG_comm_destroy(node->comm_receive);
+ node->comm_receive = NULL;
MSG_task_destroy(task_received);
task_data_destroy(req_data);
}
}
- node->comm_receive = NULL;
} while (!stop);
}
- xbt_free(mailbox);
return predecessor_id;
}
req_data->type = TASK_NOTIFY;
req_data->request_id = predecessor_candidate_id;
req_data->issuer_host_name = MSG_host_get_name(MSG_host_self());
- req_data->answer_to = NULL;
// send a "Notify" request to notify_id
m_task_t task = MSG_task_create(NULL, COMP_SIZE, COMM_SIZE, req_data);
DEBUG2("Sending a 'Notify' request (task %p) to %d", task, notify_id);
- char* mailbox = get_mailbox(notify_id);
+ char mailbox[MAILBOX_NAME_SIZE];
+ get_mailbox(notify_id, mailbox);
msg_comm_t comm = MSG_task_isend(task, mailbox);
xbt_dynar_push(node->comms, &comm);
- xbt_free(mailbox);
}
/**
// TODO
}
+/**
+ * \brief Performs a find successor request to a random id.
+ * \param node the current node
+ */
+static void random_lookup(node_t node)
+{
+ int id = 1337; // TODO pick a pseudorandom id
+ DEBUG1("Making a lookup request for id %d", id);
+ find_successor(node, id);
+}
+
/**
* \brief Main function.
*/
