X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/417742f1c7f6545db82079acd702fde03547d400..eba5ae1edf4ba60747de3d624ab2a34bdc2f5b84:/examples/msg/dht-chord/dht-chord.c diff --git a/examples/msg/dht-chord/dht-chord.c b/examples/msg/dht-chord/dht-chord.c index 800a648bcf..882359e74a 100644 --- a/examples/msg/dht-chord/dht-chord.c +++ b/examples/msg/dht-chord/dht-chord.c @@ -1,5 +1,4 @@ -/* Copyright (c) 2010-2015. The SimGrid Team. - * All rights reserved. */ +/* Copyright (c) 2010-2016. 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. */ @@ -9,15 +8,6 @@ #include #include "src/mc/mc_replay.h" // FIXME: this is an internal header -/** @addtogroup MSG_examples - * - * - chord/chord.c: Classical Chord P2P protocol - * This example implements the well known Chord P2P protocol. Its main advantage is that it constitute a fully - * working non-trivial example. In addition, its implementation is rather efficient, as demonstrated in - * http://hal.inria.fr/inria-00602216/ - */ - - XBT_LOG_NEW_DEFAULT_CATEGORY(msg_chord, "Messages specific for this msg example"); #define COMM_SIZE 10 @@ -35,8 +25,6 @@ static int periodic_lookup_delay = 10; static const double sleep_delay = 4.9999; -extern long int smx_total_comms; - /* Finger element. */ typedef struct s_finger { int id; @@ -92,11 +80,10 @@ static void print_finger_table(node_t node); static void set_finger(node_t node, int finger_index, int id); static void set_predecessor(node_t node, int predecessor_id); -// process functions -static int node(int argc, char *argv[]); +//// process functions static void handle_task(node_t node, msg_task_t task); -// Chord core +//// Chord core static void create(node_t node); static int join(node_t node, int known_id); static void leave(node_t node); @@ -109,15 +96,15 @@ static void notify(node_t node, int predecessor_candidate_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 random_lookup(node_t node); static void quit_notify(node_t node); -/* \brief Global initialization of the Chord simulation. */ +/* Global initialization of the Chord simulation. */ static void chord_initialize(void) { // compute the powers of 2 once for all powers2 = xbt_new(int, nb_bits); - int pow = 1; + unsigned int pow = 1; unsigned i; for (i = 0; i < nb_bits; i++) { powers2[i] = pow; @@ -150,21 +137,15 @@ static void chord_exit(void) xbt_free(powers2); } -/** - * \brief Turns an id into an equivalent id in [0, nb_keys). - * \param id an id - * \return the corresponding normalized id - */ +/* Turns an id into an equivalent id in [0, nb_keys). */ static int normalize(int id) { - // like id % nb_keys, but works with negatives numbers (and faster) - return id & (nb_keys - 1); + return id % nb_keys; } -/** - * \brief Returns whether an id belongs to the interval [start, end]. +/* Returns whether an id belongs to the interval [start, end]. * - * The parameters are noramlized to make sure they are between 0 and nb_keys - 1). + * The parameters are normalized to make sure they are between 0 and nb_keys - 1). * 1 belongs to [62, 3] * 1 does not belong to [3, 62] * 63 belongs to [62, 3] @@ -179,24 +160,23 @@ static int normalize(int id) */ static int is_in_interval(int id, int start, int end) { - id = normalize(id); - start = normalize(start); - end = normalize(end); + int i = normalize(id); + int s = normalize(start); + int e = normalize(end); // make sure end >= start and id >= start - if (end < start) { - end += nb_keys; + if (e < s) { + e += nb_keys; } - if (id < start) { - id += nb_keys; + if (i < s) { + i += nb_keys; } - return id <= end; + return i <= e; } -/** - * \brief Gets the mailbox name of a host given its chord id. +/* Gets the mailbox name of a host given its chord id. * \param node_id id of a node * \param mailbox pointer to where the mailbox name should be written * (there must be enough space) @@ -206,10 +186,7 @@ static void get_mailbox(int node_id, char* mailbox) snprintf(mailbox, MAILBOX_NAME_SIZE - 1, "%d", node_id); } -/** - * \brief Frees the memory used by a task. - * \param task the MSG task to destroy - */ +/* Frees the memory used by a task and destroy it */ static void task_free(void* task) { // TODO add a parameter data_free_function to MSG_task_create? @@ -219,25 +196,21 @@ static void task_free(void* task) } } -/** - * \brief Displays the finger table of a node. - * \param node a node - */ +/* Displays the finger table of a node. */ static void print_finger_table(node_t node) { if (XBT_LOG_ISENABLED(msg_chord, xbt_log_priority_verbose)) { - int i; XBT_VERB("My finger table:"); XBT_VERB("Start | Succ"); - for (i = 0; i < nb_bits; i++) { + for (int i = 0; i < nb_bits; i++) { XBT_VERB(" %3d | %3d", (node->id + powers2[i]) % nb_keys, node->fingers[i].id); } XBT_VERB("Predecessor: %d", node->pred_id); } } -/** - * \brief Sets a finger of the current node. +/* Sets a finger of the current node. + * * \param node the current node * \param finger_index index of the finger to set (0 to nb_bits - 1) * \param id the id to set for this finger @@ -252,8 +225,8 @@ static void set_finger(node_t node, int finger_index, int id) } } -/** - * \brief Sets the predecessor of the current node. +/* Sets the predecessor of the current node. + * * \param node the current node * \param id the id to predecessor, or -1 to unset the predecessor */ @@ -271,16 +244,15 @@ static void set_predecessor(node_t node, int predecessor_id) } } -/** - * \brief Node Function +/* Node main Function + * * Arguments: * - my id * - the id of a guy I know in the system (except for the first node) * - the time to sleep before I join (except for the first node) */ -int node(int argc, char *argv[]) +static int node(int argc, char *argv[]) { - /* Reduce the run size for the MC */ if(MC_is_active() || MC_record_replay_is_active()){ periodic_stabilize_delay = 8; @@ -325,14 +297,8 @@ int node(int argc, char *argv[]) } else { int known_id = xbt_str_parse_int(argv[2],"Invalid root ID: %s"); - //double sleep_time = atof(argv[3]); deadline = xbt_str_parse_double(argv[4],"Invalid deadline: %s"); - /* - // sleep before starting - XBT_DEBUG("Let's sleep during %f", sleep_time); - MSG_process_sleep(sleep_time); - */ XBT_DEBUG("Hey! Let's join the system."); join_success = join(&node, known_id); @@ -429,11 +395,10 @@ int node(int argc, char *argv[]) return 0; } -/** - * \brief This function is called when the current node receives a task. +/* This function is called when the current node receives a task. + * * \param node the current node - * \param task the task to handle (don't touch it then: - * it will be destroyed, reused or forwarded) + * \param task the task to handle (don't touch it afterward: it will be destroyed, reused or forwarded) */ static void handle_task(node_t node, msg_task_t task) { @@ -452,12 +417,9 @@ static void handle_task(node_t node, msg_task_t task) { task_data->type = TASK_FIND_SUCCESSOR_ANSWER; task_data->answer_id = node->fingers[0].id; XBT_DEBUG("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); + task_data->issuer_host_name, task_data->answer_to, task_data->request_id, task_data->answer_id); MSG_task_dsend(task, task_data->answer_to, task_free); - } - else { + } else { // otherwise, forward the request to the closest preceding finger in my table int closest = closest_preceding_node(node, task_data->request_id); XBT_DEBUG("Forwarding the 'Find Successor' request for id %d to my closest preceding finger %d", @@ -472,8 +434,7 @@ static void handle_task(node_t node, msg_task_t task) { task_data->type = TASK_GET_PREDECESSOR_ANSWER; task_data->answer_id = node->pred_id; XBT_DEBUG("Sending back a 'Get Predecessor Answer' to %s via mailbox '%s': my predecessor is %d", - task_data->issuer_host_name, - task_data->answer_to, task_data->answer_id); + task_data->issuer_host_name, task_data->answer_to, task_data->answer_id); MSG_task_dsend(task, task_data->answer_to, task_free); break; @@ -518,8 +479,7 @@ static void handle_task(node_t node, msg_task_t task) { XBT_DEBUG("Receiving a 'Predecessor Alive' request from %s", task_data->issuer_host_name); task_data->type = TASK_PREDECESSOR_ALIVE_ANSWER; XBT_DEBUG("Sending back a 'Predecessor Alive Answer' to %s (mailbox %s)", - task_data->issuer_host_name, - task_data->answer_to); + task_data->issuer_host_name, task_data->answer_to); MSG_task_dsend(task, task_data->answer_to, task_free); break; @@ -528,10 +488,7 @@ static void handle_task(node_t node, msg_task_t task) { } } -/** - * \brief Initializes the current node as the first one of the system. - * \param node the current node - */ +/* Initializes the current node as the first one of the system */ static void create(node_t node) { XBT_DEBUG("Create a new Chord ring..."); @@ -539,9 +496,8 @@ static void create(node_t node) print_finger_table(node); } -/** - * \brief Makes the current node join the ring, knowing the id of a node - * already in the ring +/* Makes the current node join the ring, knowing the id of a node already in the ring + * * \param node the current node * \param known_id id of a node already in the ring * \return 1 if the join operation succeeded, 0 otherwise @@ -551,13 +507,6 @@ static int join(node_t node, int known_id) XBT_INFO("Joining the ring with id %d, knowing node %d", node->id, known_id); set_predecessor(node, -1); // no predecessor (yet) - /* - int i; - for (i = 0; i < nb_bits; i++) { - set_finger(node, i, known_id); - } - */ - int successor_id = remote_find_successor(node, known_id, node->id); if (successor_id == -1) { XBT_INFO("Cannot join the ring."); @@ -570,21 +519,14 @@ static int join(node_t node, int known_id) return successor_id != -1; } -/** - * \brief Makes the current node quit the system - * \param node the current node - */ +/* Makes the current node quit the system */ static void leave(node_t node) { XBT_DEBUG("Well Guys! I Think it's time for me to quit ;)"); quit_notify(node); } -/** - * \brief Notifies the successor and the predecessor of the current node - * of the departure - * \param node the current node - */ +/* Notifies the successor and the predecessor of the current node before leaving */ static void quit_notify(node_t node) { char mailbox[MAILBOX_NAME_SIZE]; @@ -597,10 +539,8 @@ static void quit_notify(node_t node) 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); - if (MSG_task_send_with_timeout(task_sent, node->fingers[0].mailbox, timeout)== - MSG_TIMEOUT) { - XBT_DEBUG("Timeout expired when sending a 'PREDECESSOR_LEAVING' to my successor %d", - node->fingers[0].id); + if (MSG_task_send_with_timeout(task_sent, node->fingers[0].mailbox, timeout)== MSG_TIMEOUT) { + XBT_DEBUG("Timeout expired when sending a 'PREDECESSOR_LEAVING' to my successor %d", node->fingers[0].id); task_free(task_sent); } @@ -615,17 +555,14 @@ static void quit_notify(node_t node) 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); - if (MSG_task_send_with_timeout(task_sent_s, mailbox, timeout)== - MSG_TIMEOUT) { - XBT_DEBUG("Timeout expired when sending a 'SUCCESSOR_LEAVING' to my predecessor %d", - node->pred_id); + if (MSG_task_send_with_timeout(task_sent_s, mailbox, timeout)== MSG_TIMEOUT) { + XBT_DEBUG("Timeout expired when sending a 'SUCCESSOR_LEAVING' to my predecessor %d", node->pred_id); task_free(task_sent_s); } - } -/** - * \brief Makes the current node find the successor node of an id. +/* Makes the current node find the successor node of an id. + * * \param node the current node * \param id the id to find * \return the id of the successor node, or -1 if the request failed @@ -642,8 +579,8 @@ static int find_successor(node_t node, int id) return remote_find_successor(node, closest, id); } -/** - * \brief Asks another node the successor node of an id. +/* \brief Asks another node the successor node of an id. + * * \param node the current node * \param ask_to the node to ask to * \param id the id to find @@ -667,8 +604,7 @@ static int remote_find_successor(node_t node, int ask_to, int id) msg_error_t res = MSG_task_send_with_timeout(task_sent, mailbox, timeout); if (res != MSG_OK) { - XBT_DEBUG("Failed to send the 'Find Successor' request (task %p) to %d for id %d", - task_sent, ask_to, id); + XBT_DEBUG("Failed to send the 'Find Successor' request (task %p) to %d for id %d", task_sent, ask_to, id); task_free(task_sent); } else { @@ -700,7 +636,7 @@ static int remote_find_successor(node_t node, int ask_to, int id) // 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. + // We failed to find this bug directly, as it only occurred 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); @@ -735,8 +671,8 @@ static int remote_find_successor(node_t node, int ask_to, int id) return successor; } -/** - * \brief Asks another node its predecessor. +/* Asks its predecessor to a remote node + * * \param node the current node * \param ask_to the node to ask to * \return the id of its predecessor node, or -1 if the request failed @@ -814,14 +750,13 @@ static int remote_get_predecessor(node_t node, int ask_to) return predecessor_id; } -/** - * \brief Returns the closest preceding finger of an id - * with respect to the finger table of the current node. +/* Returns the closest preceding finger of an id with respect to the finger table of the current node. + * * \param node the current node * \param id the id to find * \return the closest preceding finger of that id */ -int closest_preceding_node(node_t node, int id) +static int closest_preceding_node(node_t node, int id) { int i; for (i = nb_bits - 1; i >= 0; i--) { @@ -832,11 +767,7 @@ int closest_preceding_node(node_t node, int id) return node->id; } -/** - * \brief This function is called periodically. It checks the immediate - * successor of the current node. - * \param node the current node - */ +/* This function is called periodically. It checks the immediate successor of the current node. */ static void stabilize(node_t node) { XBT_DEBUG("Stabilizing node"); @@ -861,11 +792,7 @@ static void stabilize(node_t node) } } -/** - * \brief Notifies the current node that its predecessor may have changed. - * \param node the current node - * \param candidate_id the possible new predecessor - */ +/* Notifies the current node that its predecessor may have changed. */ static void notify(node_t node, int predecessor_candidate_id) { if (node->pred_id == -1 @@ -879,12 +806,7 @@ static void notify(node_t node, int predecessor_candidate_id) { } } -/** - * \brief Notifies a remote node that its predecessor may have changed. - * \param node the current node - * \param notify_id id of the node to notify - * \param candidate_id the possible new predecessor - */ +/* Notifies a remote node that its predecessor may have changed. */ 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); @@ -900,11 +822,7 @@ static void remote_notify(node_t node, int notify_id, int predecessor_candidate_ MSG_task_dsend(task, mailbox, task_free); } -/** - * \brief This function is called periodically. - * It refreshes the finger table of the current node. - * \param node the current node - */ +/* refreshes the finger table of the current node (called periodically) */ static void fix_fingers(node_t node) { XBT_DEBUG("Fixing fingers"); @@ -920,11 +838,7 @@ static void fix_fingers(node_t node) { } } -/** - * \brief This function is called periodically. - * It checks whether the predecessor has failed - * \param node the current node - */ +/* checks whether the predecessor has failed (called periodically) */ static void check_predecessor(node_t node) { XBT_DEBUG("Checking whether my predecessor is alive"); @@ -990,10 +904,7 @@ static void check_predecessor(node_t node) } } -/** - * \brief Performs a find successor request to a random id. - * \param node the current node - */ +/* Performs a find successor request to a random id */ static void random_lookup(node_t node) { int random_index = RngStream_RandInt (node->stream, 0, nb_bits - 1); @@ -1044,7 +955,6 @@ int main(int argc, char *argv[]) MSG_launch_application(application_file); msg_error_t res = MSG_main(); - XBT_CRITICAL("Messages created: %ld", smx_total_comms); XBT_INFO("Simulated time: %g", MSG_get_clock()); chord_exit();