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[simgrid.git] / src / smpi / src / smpi_base.c
index f80e950..7d66cf0 100644 (file)
@@ -1,58 +1,16 @@
 #include <stdio.h>
-
 #include <signal.h>
 #include <sys/time.h>
-#include "xbt/xbt_os_time.h"
-#include "simix/simix.h"
-#include "simix/private.h"
-#include "smpi.h"
-
-// FIXME: move globals into structure...
-
-xbt_mallocator_t smpi_request_mallocator      = NULL;
-xbt_mallocator_t smpi_message_mallocator      = NULL;
-
-xbt_fifo_t *smpi_pending_send_requests        = NULL;
-smx_mutex_t *smpi_pending_send_requests_mutex = NULL;
-
-xbt_fifo_t *smpi_pending_recv_requests        = NULL;
-smx_mutex_t *smpi_pending_recv_requests_mutex = NULL;
-
-xbt_fifo_t *smpi_received_messages            = NULL;
-smx_mutex_t *smpi_received_messages_mutex     = NULL;
-
-smx_process_t *smpi_sender_processes        = NULL;
-smx_process_t *smpi_receiver_processes      = NULL;
-
-int smpi_running_hosts = 0;
-
-smpi_mpi_communicator_t smpi_mpi_comm_world;
-
-smpi_mpi_status_t smpi_mpi_status_ignore;
-
-smpi_mpi_datatype_t smpi_mpi_byte;
-smpi_mpi_datatype_t smpi_mpi_int;
-smpi_mpi_datatype_t smpi_mpi_double;
 
-smpi_mpi_op_t smpi_mpi_land;
-smpi_mpi_op_t smpi_mpi_sum;
+#include "private.h"
 
-static xbt_os_timer_t smpi_timer;
-static int smpi_benchmarking;
-static double smpi_reference_speed;
+SMPI_Global_t     smpi_global     = NULL;
 
-// mutexes
-smx_mutex_t smpi_running_hosts_mutex = NULL;
-smx_mutex_t smpi_benchmarking_mutex  = NULL;
-smx_mutex_t init_mutex = NULL;
-smx_cond_t init_cond  = NULL;
-
-int smpi_root_ready = 0;
-int smpi_ready_count = 0;
+SMPI_MPI_Global_t smpi_mpi_global = NULL;
 
 XBT_LOG_NEW_DEFAULT_CATEGORY(smpi, "SMPI");
 
-int inline smpi_mpi_comm_size(smpi_mpi_communicator_t *comm) 
+int inline smpi_mpi_comm_size(smpi_mpi_communicator_t *comm)
 {
        return comm->size;
 }
@@ -74,7 +32,7 @@ int inline smpi_mpi_comm_rank_self(smpi_mpi_communicator_t *comm)
 
 int inline smpi_mpi_comm_world_rank_self()
 {
-       return smpi_mpi_comm_rank(&smpi_mpi_comm_world, SIMIX_host_self())
+       return smpi_mpi_comm_rank(smpi_mpi_global->mpi_comm_world, SIMIX_host_self());
 }
 
 int smpi_sender(int argc, char **argv)
@@ -82,50 +40,53 @@ int smpi_sender(int argc, char **argv)
        smx_process_t self;
        smx_host_t shost;
        int rank;
+
        xbt_fifo_t request_queue;
        smx_mutex_t request_queue_mutex;
        int size;
-       int running_hosts = 0;
+
+       int running_hosts_count;
+
        smpi_mpi_request_t *request;
+
        smx_host_t dhost;
+
        smx_action_t communicate_action;
-       smpi_received_message_t *scratch;
+
+       smpi_received_message_t *message;
+
        int drank;
-       smx_process_t waitproc;
+
+       smx_process_t receiver_process;
 
        self  = SIMIX_process_self();
        shost = SIMIX_host_self();
-       rank  = smpi_mpi_comm_rank(&smpi_mpi_comm_world, shost);
+       rank  = smpi_mpi_comm_rank(smpi_mpi_global->mpi_comm_world, shost);
 
        // make sure root is done before own initialization
-       SIMIX_mutex_lock(init_mutex);
-       if (!smpi_root_ready) {
-               SIMIX_cond_wait(init_cond, init_mutex);
+       SIMIX_mutex_lock(smpi_global->start_stop_mutex);
+       if (!smpi_global->root_ready) {
+               SIMIX_cond_wait(smpi_global->start_stop_cond, smpi_global->start_stop_mutex);
        }
-       SIMIX_mutex_unlock(init_mutex);
-
-       request_queue       = smpi_pending_send_requests[rank];
-       request_queue_mutex = smpi_pending_send_requests_mutex[rank];
+       SIMIX_mutex_unlock(smpi_global->start_stop_mutex);
 
-       size = smpi_mpi_comm_size(&smpi_mpi_comm_world);
+       request_queue       = smpi_global->pending_send_request_queues[rank];
+       request_queue_mutex = smpi_global->pending_send_request_queues_mutexes[rank];
+       size                = smpi_mpi_comm_size(smpi_mpi_global->mpi_comm_world);
 
-       smpi_sender_processes[rank] = self;
+       smpi_global->sender_processes[rank] = self;
 
        // wait for all nodes to signal initializatin complete
-       SIMIX_mutex_lock(init_mutex);
-       smpi_ready_count++;
-       if (smpi_ready_count < 3 * size) {
-               SIMIX_cond_wait(init_cond, init_mutex);
+       SIMIX_mutex_lock(smpi_global->start_stop_mutex);
+       smpi_global->ready_process_count++;
+       if (smpi_global->ready_process_count < 3 * size) {
+               SIMIX_cond_wait(smpi_global->start_stop_cond, smpi_global->start_stop_mutex);
        } else {
-               SIMIX_cond_broadcast(init_cond);
+               SIMIX_cond_broadcast(smpi_global->start_stop_cond);
        }
-       SIMIX_mutex_unlock(init_mutex);
-
-       SIMIX_mutex_lock(smpi_running_hosts_mutex);
-       running_hosts = smpi_running_hosts;
-       SIMIX_mutex_unlock(smpi_running_hosts_mutex);
+       SIMIX_mutex_unlock(smpi_global->start_stop_mutex);
 
-       while (0 < running_hosts) {
+       do {
 
                SIMIX_mutex_lock(request_queue_mutex);
                request = xbt_fifo_shift(request_queue);
@@ -134,11 +95,27 @@ int smpi_sender(int argc, char **argv)
                if (NULL == request) {
                        SIMIX_process_suspend(self);
                } else {
+
                        SIMIX_mutex_lock(request->mutex);
 
+                       // copy request to appropriate received queue
+                       message       = xbt_mallocator_get(smpi_global->message_mallocator);
+                       message->comm = request->comm;
+                       message->src  = request->src;
+                       message->dst  = request->dst;
+                       message->tag  = request->tag;
+                       message->buf  = xbt_malloc(request->datatype->size * request->count);
+                       memcpy(message->buf, request->buf, request->datatype->size * request->count);
+
                        dhost = request->comm->hosts[request->dst];
+                       drank = smpi_mpi_comm_rank(smpi_mpi_global->mpi_comm_world, dhost);
+
+                       SIMIX_mutex_lock(smpi_global->received_message_queues_mutexes[drank]);
+                       xbt_fifo_push(smpi_global->received_message_queues[drank], message);
+                       SIMIX_mutex_unlock(smpi_global->received_message_queues_mutexes[drank]);
+
+                       request->completed = 1;
 
-                       // FIXME: not at all sure I can assume magic just happens here....
                        communicate_action = SIMIX_action_communicate(shost, dhost,
                                "communication", request->datatype->size * request->count * 1.0, -1.0);
 
@@ -147,36 +124,31 @@ int smpi_sender(int argc, char **argv)
 
                        SIMIX_cond_wait(request->cond, request->mutex);
 
-                       // copy request to appropriate received queue
-                       scratch = xbt_mallocator_get(smpi_message_mallocator);
-                       scratch->comm = request->comm;
-                       scratch->src  = request->src;
-                       scratch->dst  = request->dst;
-                       scratch->tag  = request->tag;
-                       scratch->buf  = request->buf;
-                       drank = smpi_mpi_comm_rank(&smpi_mpi_comm_world, dhost);
-                       SIMIX_mutex_lock(smpi_received_messages_mutex[drank]);
-                       xbt_fifo_push(smpi_received_messages[drank], scratch);
-                       SIMIX_mutex_unlock(smpi_received_messages_mutex[drank]);
-
-                       request->completed = 1;
+                       SIMIX_mutex_unlock(request->mutex);
 
-                       // wake up receiver, then any waiting sender
-                       waitproc = smpi_receiver_processes[drank];
+                       // wake up receiver if necessary
+                       receiver_process = smpi_global->receiver_processes[drank];
 
-                       do {
-                               if (SIMIX_process_is_suspended(waitproc)) {
-                                       SIMIX_process_resume(waitproc);
-                               }
-                       } while(waitproc = xbt_fifo_shift(request->waitlist));
+                       if (SIMIX_process_is_suspended(receiver_process)) {
+                               SIMIX_process_resume(receiver_process);
+                       }
 
-                       SIMIX_mutex_unlock(request->mutex);
                }
 
-               SIMIX_mutex_lock(smpi_running_hosts_mutex);
-               running_hosts = smpi_running_hosts;
-               SIMIX_mutex_unlock(smpi_running_hosts_mutex);
+               SIMIX_mutex_lock(smpi_global->running_hosts_count_mutex);
+               running_hosts_count = smpi_global->running_hosts_count;
+               SIMIX_mutex_unlock(smpi_global->running_hosts_count_mutex);
+
+       } while (0 < running_hosts_count);
+
+       SIMIX_mutex_lock(smpi_global->start_stop_mutex);
+       smpi_global->ready_process_count--;
+       if (smpi_global->ready_process_count == 0) {
+               SIMIX_cond_broadcast(smpi_global->start_stop_cond);
+       } else if (smpi_global->ready_process_count < 0) {
+               // FIXME: can't happen! abort!
        }
+       SIMIX_mutex_unlock(smpi_global->start_stop_mutex);
 
        return 0;
 }
@@ -185,58 +157,61 @@ int smpi_receiver(int argc, char **argv)
 {
        smx_process_t self;
        int rank;
+
        xbt_fifo_t request_queue;
        smx_mutex_t request_queue_mutex;
        xbt_fifo_t message_queue;
        smx_mutex_t message_queue_mutex;
        int size;
-       int running_hosts;
-       xbt_fifo_item_t request_item, message_item;
+
+       int running_hosts_count;
+
        smpi_mpi_request_t *request;
        smpi_received_message_t *message;
+
+       xbt_fifo_item_t request_item;
+       xbt_fifo_item_t message_item;
+
        smx_process_t waitproc;
 
        self  = SIMIX_process_self();
        rank  = smpi_mpi_comm_world_rank_self();
 
        // make sure root is done before own initialization
-       SIMIX_mutex_lock(init_mutex);
-       if (!smpi_root_ready) {
-               SIMIX_cond_wait(init_cond, init_mutex);
+       SIMIX_mutex_lock(smpi_global->start_stop_mutex);
+       if (!smpi_global->root_ready) {
+               SIMIX_cond_wait(smpi_global->start_stop_cond, smpi_global->start_stop_mutex);
        }
-       SIMIX_mutex_unlock(init_mutex);
+       SIMIX_mutex_unlock(smpi_global->start_stop_mutex);
 
-       request_queue       = smpi_pending_recv_requests[rank];
-       request_queue_mutex = smpi_pending_recv_requests_mutex[rank];
+       request_queue       = smpi_global->pending_recv_request_queues[rank];
+       request_queue_mutex = smpi_global->pending_recv_request_queues_mutexes[rank];
+       message_queue       = smpi_global->received_message_queues[rank];
+       message_queue_mutex = smpi_global->received_message_queues_mutexes[rank];
+       size                = smpi_mpi_comm_size(smpi_mpi_global->mpi_comm_world);
 
-       message_queue       = smpi_received_messages[rank];
-       message_queue_mutex = smpi_received_messages_mutex[rank];
-
-       size = smpi_mpi_comm_size(&smpi_mpi_comm_world);
-       smpi_receiver_processes[rank] = self;
+       smpi_global->receiver_processes[rank] = self;
 
        // wait for all nodes to signal initializatin complete
-       SIMIX_mutex_lock(init_mutex);
-       smpi_ready_count++;
-       if (smpi_ready_count < 3 * size) {
-               SIMIX_cond_wait(init_cond, init_mutex);
+       SIMIX_mutex_lock(smpi_global->start_stop_mutex);
+       smpi_global->ready_process_count++;
+       if (smpi_global->ready_process_count < 3 * size) {
+               SIMIX_cond_wait(smpi_global->start_stop_cond, smpi_global->start_stop_mutex);
        } else {
-               SIMIX_cond_broadcast(init_cond);
+               SIMIX_cond_broadcast(smpi_global->start_stop_cond);
        }
-       SIMIX_mutex_unlock(init_mutex);
-
-       SIMIX_mutex_lock(smpi_running_hosts_mutex);
-       running_hosts = smpi_running_hosts;
-       SIMIX_mutex_unlock(smpi_running_hosts_mutex);
+       SIMIX_mutex_unlock(smpi_global->start_stop_mutex);
 
-       while (0 < running_hosts) {
+       do {
+               request = NULL;
+               message = NULL;
 
                // FIXME: better algorithm, maybe some kind of balanced tree? or a heap?
 
                // FIXME: not the best way to request multiple locks...
                SIMIX_mutex_lock(request_queue_mutex);
                SIMIX_mutex_lock(message_queue_mutex);
-search:        for (request_item = xbt_fifo_get_first_item(request_queue);
+               for (request_item = xbt_fifo_get_first_item(request_queue);
                        NULL != request_item;
                        request_item = xbt_fifo_get_next_item(request_item)) {
                        request = xbt_fifo_get_item_content(request_item);
@@ -249,10 +224,11 @@ search:   for (request_item = xbt_fifo_get_first_item(request_queue);
                                                request->tag == message->tag) {
                                        xbt_fifo_remove_item(request_queue, request_item);
                                        xbt_fifo_remove_item(message_queue, message_item);
-                                       break search;
+                                       goto stopsearch;
                                }
                        }
                }
+stopsearch:
                SIMIX_mutex_unlock(message_queue_mutex);
                SIMIX_mutex_unlock(request_queue_mutex);
 
@@ -260,28 +236,183 @@ search:  for (request_item = xbt_fifo_get_first_item(request_queue);
                        SIMIX_process_suspend(self);
                } else {
                        SIMIX_mutex_lock(request->mutex);
-                       memcpy(request->buf, message->buf, request->count * request->datatype->size);
+
+                       memcpy(request->buf, message->buf, request->datatype->size * request->count);
                        request->src = message->src;
                        request->completed = 1;
+                       SIMIX_cond_broadcast(request->cond);
 
-                       while (waitproc = xbt_fifo_shift(request->waitlist)) {
-                               if (SIMIX_process_is_suspended(waitproc)) {
-                                       SIMIX_process_resume(waitproc);
-                               }
-                       }
                        SIMIX_mutex_unlock(request->mutex);
 
-                       xbt_mallocator_release(smpi_message_mallocator, message);
+                       xbt_free(message->buf);
+                       xbt_mallocator_release(smpi_global->message_mallocator, message);
                }
 
-               SIMIX_mutex_lock(smpi_running_hosts_mutex);
-               running_hosts = smpi_running_hosts;
-               SIMIX_mutex_unlock(smpi_running_hosts_mutex);
+               SIMIX_mutex_lock(smpi_global->running_hosts_count_mutex);
+               running_hosts_count = smpi_global->running_hosts_count;
+               SIMIX_mutex_unlock(smpi_global->running_hosts_count_mutex);
+
+       } while (0 < running_hosts_count);
+
+       SIMIX_mutex_lock(smpi_global->start_stop_mutex);
+       smpi_global->ready_process_count--;
+       if (smpi_global->ready_process_count == 0) {
+               SIMIX_cond_broadcast(smpi_global->start_stop_cond);
+       } else if (smpi_global->ready_process_count < 0) {
+               // FIXME: can't happen, abort!
        }
+       SIMIX_mutex_unlock(smpi_global->start_stop_mutex);
 
        return 0;
 }
 
+void *smpi_request_new()
+{
+       smpi_mpi_request_t *request = xbt_new(smpi_mpi_request_t, 1);
+
+       request->completed = 0;
+       request->mutex     = SIMIX_mutex_init();
+       request->cond      = SIMIX_cond_init();
+
+       return request;
+}
+
+void smpi_request_free(void *pointer) {
+
+       smpi_mpi_request_t *request = pointer;
+
+       if (NULL != request) {
+               SIMIX_cond_destroy(request->cond);
+               SIMIX_mutex_destroy(request->mutex);
+               xbt_free(request);
+       }
+
+       return;
+}
+
+void smpi_request_reset(void *pointer) {
+       return;
+}
+
+
+void *smpi_message_new()
+{
+       return xbt_new(smpi_received_message_t, 1);
+}
+
+void smpi_message_free(void *pointer)
+{
+       if (NULL != pointer) {
+               xbt_free(pointer);
+       }
+
+       return;
+}
+
+void smpi_message_reset(void *pointer)
+{
+       return;
+}
+
+void smpi_global_init()
+{
+       int i;
+
+       int size = SIMIX_host_get_number();
+
+       smpi_global = xbt_new(s_SMPI_Global_t, 1);
+
+       // config variable
+       smpi_global->reference_speed                     = SMPI_DEFAULT_SPEED;
+
+       smpi_global->root_ready                          = 0;
+       smpi_global->ready_process_count                 = 0;
+
+       // start/stop
+       smpi_global->start_stop_mutex                    = SIMIX_mutex_init();
+       smpi_global->start_stop_cond                     = SIMIX_cond_init();
+
+       // processes
+       smpi_global->sender_processes                    = xbt_new(smx_process_t, size);
+       smpi_global->receiver_processes                  = xbt_new(smx_process_t, size);
+
+       // running hosts
+       smpi_global->running_hosts_count_mutex           = SIMIX_mutex_init();
+        smpi_global->running_hosts_count                 = 0;
+
+       // mallocators
+       smpi_global->request_mallocator                  = xbt_mallocator_new(SMPI_REQUEST_MALLOCATOR_SIZE,
+                                                            smpi_request_new, smpi_request_free, smpi_request_reset);
+       smpi_global->message_mallocator                  = xbt_mallocator_new(SMPI_MESSAGE_MALLOCATOR_SIZE,
+                                                            smpi_message_new, smpi_message_free, smpi_message_reset);
+
+       //
+       smpi_global->pending_send_request_queues         = xbt_new(xbt_fifo_t,  size);
+       smpi_global->pending_send_request_queues_mutexes = xbt_new(smx_mutex_t, size);
+       smpi_global->pending_recv_request_queues         = xbt_new(xbt_fifo_t,  size);
+       smpi_global->pending_recv_request_queues_mutexes = xbt_new(smx_mutex_t, size);
+       smpi_global->received_message_queues             = xbt_new(xbt_fifo_t,  size);
+       smpi_global->received_message_queues_mutexes     = xbt_new(smx_mutex_t, size);
+       smpi_global->timers                              = xbt_new(xbt_os_timer_t, size);
+       smpi_global->timers_mutexes                      = xbt_new(smx_mutex_t, size);
+
+       for(i = 0; i < size; i++) {
+               smpi_global->pending_send_request_queues[i]         = xbt_fifo_new();
+               smpi_global->pending_send_request_queues_mutexes[i] = SIMIX_mutex_init();
+               smpi_global->pending_recv_request_queues[i]         = xbt_fifo_new();
+               smpi_global->pending_recv_request_queues_mutexes[i] = SIMIX_mutex_init();
+               smpi_global->received_message_queues[i]             = xbt_fifo_new();
+               smpi_global->received_message_queues_mutexes[i]     = SIMIX_mutex_init();
+               smpi_global->timers[i]                              = xbt_os_timer_new();
+               smpi_global->timers_mutexes[i]                      = SIMIX_mutex_init();
+       }
+
+}
+
+void smpi_global_destroy()
+{
+       int i;
+
+       int size = SIMIX_host_get_number();
+
+       // start/stop
+       SIMIX_mutex_destroy(smpi_global->start_stop_mutex);
+       SIMIX_cond_destroy(smpi_global->start_stop_cond);
+
+       // processes
+       xbt_free(smpi_global->sender_processes);
+       xbt_free(smpi_global->receiver_processes);
+
+       // running hosts
+       SIMIX_mutex_destroy(smpi_global->running_hosts_count_mutex);
+
+       // mallocators
+       xbt_mallocator_free(smpi_global->request_mallocator);
+       xbt_mallocator_free(smpi_global->message_mallocator);
+
+       for(i = 0; i < size; i++) {
+               xbt_fifo_free(smpi_global->pending_send_request_queues[i]);
+               SIMIX_mutex_destroy(smpi_global->pending_send_request_queues_mutexes[i]);
+               xbt_fifo_free(smpi_global->pending_recv_request_queues[i]);
+               SIMIX_mutex_destroy(smpi_global->pending_recv_request_queues_mutexes[i]);
+               xbt_fifo_free(smpi_global->received_message_queues[i]);
+               SIMIX_mutex_destroy(smpi_global->received_message_queues_mutexes[i]);
+               xbt_os_timer_free(smpi_global->timers[i]);
+               SIMIX_mutex_destroy(smpi_global->timers_mutexes[i]);
+       }
+
+       xbt_free(smpi_global->pending_send_request_queues);
+       xbt_free(smpi_global->pending_send_request_queues_mutexes);
+       xbt_free(smpi_global->pending_recv_request_queues);
+       xbt_free(smpi_global->pending_recv_request_queues_mutexes);
+       xbt_free(smpi_global->received_message_queues);
+       xbt_free(smpi_global->received_message_queues_mutexes);
+       xbt_free(smpi_global->timers);
+       xbt_free(smpi_global->timers_mutexes);
+
+       xbt_free(smpi_global);
+}
+
 int smpi_run_simulation(int argc, char **argv)
 {
        smx_cond_t   cond           = NULL;
@@ -294,16 +425,20 @@ int smpi_run_simulation(int argc, char **argv)
 
        SIMIX_global_init(&argc, argv);
 
-       init_mutex = SIMIX_mutex_init();
-       init_cond  = SIMIX_cond_init();
-
        SIMIX_function_register("smpi_simulated_main", smpi_simulated_main);
-       SIMIX_function_register("smpi_sender", smpi_sender);
-       SIMIX_function_register("smpi_receiver", smpi_receiver);
+       SIMIX_function_register("smpi_sender",         smpi_sender);
+       SIMIX_function_register("smpi_receiver",       smpi_receiver);
+
+       // FIXME: ought to verify these files...
        SIMIX_create_environment(argv[1]);
+
+       // must initialize globals between creating environment and launching app....
+       smpi_global_init();
+
        SIMIX_launch_application(argv[2]);
 
        /* Prepare to display some more info when dying on Ctrl-C pressing */
+       // FIXME: doesn't work
        //signal(SIGINT, inthandler);
 
        /* Clean IO before the run */
@@ -326,10 +461,16 @@ int smpi_run_simulation(int argc, char **argv)
                        SIMIX_action_destroy(action);
                }
        }
+
        xbt_fifo_free(actions_failed);
        xbt_fifo_free(actions_done);
+
        INFO1("simulation time %g", SIMIX_get_clock());
+
+       smpi_global_destroy();
+
        SIMIX_clean();
+
        return 0;
 }
 
@@ -343,196 +484,191 @@ void smpi_mpi_sum_func(void *x, void *y, void *z)
        *(int *)z = *(int *)x + *(int *)y;
 }
 
-smpi_mpi_request_t *smpi_new_request()
-{
-       return xbt_new(smpi_mpi_request_t, 1);
-}
 
 void smpi_mpi_init()
 {
        int i;
-       int size;
        smx_process_t process;
-       smx_host_t *hosts;
        smx_host_t host;
+       smx_host_t *hosts;
+       int size;
        double duration;
 
+       SIMIX_mutex_lock(smpi_global->running_hosts_count_mutex);
+       smpi_global->running_hosts_count++;
+       SIMIX_mutex_unlock(smpi_global->running_hosts_count_mutex);
+
        // initialize some local variables
-       host  = SIMIX_host_self();
-       hosts = SIMIX_host_get_table();
-       size  = SIMIX_host_get_number();
+       process = SIMIX_process_self();
+       host    = SIMIX_host_self();
+       hosts   = SIMIX_host_get_table();
+       size    = SIMIX_host_get_number();
 
        // node 0 sets the globals
        if (host == hosts[0]) {
 
-               // processes
-               smpi_sender_processes             = xbt_new(smx_process_t, size);
-               smpi_receiver_processes           = xbt_new(smx_process_t, size);
-
-               // running hosts
-               smpi_running_hosts_mutex          = SIMIX_mutex_init();
-               smpi_running_hosts                = size;
+               smpi_mpi_global                                = xbt_new(s_SMPI_MPI_Global_t, 1);
 
                // global communicator
-               smpi_mpi_comm_world.size          = size;
-               smpi_mpi_comm_world.barrier       = 0;
-               smpi_mpi_comm_world.barrier_mutex = SIMIX_mutex_init();
-               smpi_mpi_comm_world.barrier_cond  = SIMIX_cond_init();
-               smpi_mpi_comm_world.hosts         = hosts;
-               smpi_mpi_comm_world.processes     = xbt_new(smx_process_t, size);
-               smpi_mpi_comm_world.processes[0]  = SIMIX_process_self();
+               smpi_mpi_global->mpi_comm_world                = xbt_new(smpi_mpi_communicator_t, 1);
+               smpi_mpi_global->mpi_comm_world->size          = size;
+               smpi_mpi_global->mpi_comm_world->barrier_count = 0;
+               smpi_mpi_global->mpi_comm_world->barrier_mutex = SIMIX_mutex_init();
+               smpi_mpi_global->mpi_comm_world->barrier_cond  = SIMIX_cond_init();
+               smpi_mpi_global->mpi_comm_world->hosts         = hosts;
+               smpi_mpi_global->mpi_comm_world->processes     = xbt_new(smx_process_t, size);
+               smpi_mpi_global->mpi_comm_world->processes[0]  = process;
 
                // mpi datatypes
-               smpi_mpi_byte.size                = (size_t)1;
-               smpi_mpi_int.size                 = sizeof(int);
-               smpi_mpi_double.size              = sizeof(double);
+               smpi_mpi_global->mpi_byte                      = xbt_new(smpi_mpi_datatype_t, 1);
+               smpi_mpi_global->mpi_byte->size                = (size_t)1;
+               smpi_mpi_global->mpi_int                       = xbt_new(smpi_mpi_datatype_t, 1);
+               smpi_mpi_global->mpi_int->size                 = sizeof(int);
+               smpi_mpi_global->mpi_double                    = xbt_new(smpi_mpi_datatype_t, 1);
+               smpi_mpi_global->mpi_double->size              = sizeof(double);
 
                // mpi operations
-               smpi_mpi_land.func                = &smpi_mpi_land_func;
-               smpi_mpi_sum.func                 = &smpi_mpi_sum_func;
-
-               // smpi globals
-               smpi_request_mallocator           = xbt_mallocator_new(SMPI_REQUEST_MALLOCATOR_SIZE, smpi_new_request, xbt_free, NULL);
-               smpi_message_mallocator           = xbt_mallocator_new(SMPI_MESSAGE_MALLOCATOR_SIZE, smpi_new_message, xbt_free, NULL);
-               smpi_pending_send_requests        = xbt_new(xbt_fifo_t,  size);
-               smpi_pending_send_requests_mutex  = xbt_new(smx_mutex_t, size);
-               smpi_pending_recv_requests        = xbt_new(xbt_fifo_t,  size);
-               smpi_pending_recv_requests_mutex  = xbt_new(smx_mutex_t, size);
-               smpi_received_messages            = xbt_new(xbt_fifo_t,  size);
-               smpi_received_messages_mutex      = xbt_new(smx_mutex_t, size);
-
-               for(i = 0; i < size; i++) {
-                       smpi_pending_send_requests[i]       = xbt_fifo_new();
-                       smpi_pending_send_requests_mutex[i] = SIMIX_mutex_init();
-                       smpi_pending_recv_requests[i]       = xbt_fifo_new();
-                       smpi_pending_recv_requests_mutex[i] = SIMIX_mutex_init();
-                       smpi_received_messages[i]           = xbt_fifo_new();
-                       smpi_received_messages_mutex[i]     = SIMIX_mutex_init();
-               }
-
-               smpi_timer                      = xbt_os_timer_new();
-               smpi_reference_speed            = SMPI_DEFAULT_SPEED;
-               smpi_benchmarking               = 0;
-               smpi_benchmarking_mutex         = SIMIX_mutex_init();
+               smpi_mpi_global->mpi_land                      = xbt_new(smpi_mpi_op_t, 1);
+               smpi_mpi_global->mpi_land->func                = smpi_mpi_land_func;
+               smpi_mpi_global->mpi_sum                       = xbt_new(smpi_mpi_op_t, 1);
+               smpi_mpi_global->mpi_sum->func                 = smpi_mpi_sum_func;
 
                // signal all nodes to perform initialization
-               SIMIX_mutex_lock(init_mutex);
-               smpi_root_ready = 1;
-               SIMIX_cond_broadcast(init_cond);
-               SIMIX_mutex_unlock(init_mutex);
+               SIMIX_mutex_lock(smpi_global->start_stop_mutex);
+               smpi_global->root_ready = 1;
+               SIMIX_cond_broadcast(smpi_global->start_stop_cond);
+               SIMIX_mutex_unlock(smpi_global->start_stop_mutex);
 
        } else {
 
                // make sure root is done before own initialization
-               SIMIX_mutex_lock(init_mutex);
-               if (!smpi_root_ready) {
-                       SIMIX_cond_wait(init_cond, init_mutex);
+               SIMIX_mutex_lock(smpi_global->start_stop_mutex);
+               if (!smpi_global->root_ready) {
+                       SIMIX_cond_wait(smpi_global->start_stop_cond, smpi_global->start_stop_mutex);
                }
-               SIMIX_mutex_unlock(init_mutex);
-
-               smpi_mpi_comm_world.processes[smpi_mpi_comm_rank_self(&smpi_mpi_comm_world)] = SIMIX_process_self();
+               SIMIX_mutex_unlock(smpi_global->start_stop_mutex);
 
+               smpi_mpi_global->mpi_comm_world->processes[smpi_mpi_comm_world_rank_self()] = process;
        }
 
        // wait for all nodes to signal initializatin complete
-       SIMIX_mutex_lock(init_mutex);
-       smpi_ready_count++;
-       if (smpi_ready_count < 3 * size) {
-               SIMIX_cond_wait(init_cond, init_mutex);
+       SIMIX_mutex_lock(smpi_global->start_stop_mutex);
+       smpi_global->ready_process_count++;
+       if (smpi_global->ready_process_count < 3 * size) {
+               SIMIX_cond_wait(smpi_global->start_stop_cond, smpi_global->start_stop_mutex);
        } else {
-               SIMIX_cond_broadcast(init_cond);
+               SIMIX_cond_broadcast(smpi_global->start_stop_cond);
        }
-       SIMIX_mutex_unlock(init_mutex);
+       SIMIX_mutex_unlock(smpi_global->start_stop_mutex);
 
+       return;
 }
 
 void smpi_mpi_finalize()
 {
        int i;
 
-       SIMIX_mutex_lock(smpi_running_hosts_mutex);
-       i = --smpi_running_hosts;
-       SIMIX_mutex_unlock(smpi_running_hosts_mutex);
+       SIMIX_mutex_lock(smpi_global->running_hosts_count_mutex);
+       i = --smpi_global->running_hosts_count;
+       SIMIX_mutex_unlock(smpi_global->running_hosts_count_mutex);
+
+       SIMIX_mutex_lock(smpi_global->start_stop_mutex);
+       smpi_global->ready_process_count--;
+       SIMIX_mutex_unlock(smpi_global->start_stop_mutex);
 
        if (0 >= i) {
 
-               SIMIX_mutex_destroy(smpi_running_hosts_mutex);
+               // wake up senders/receivers
+               for (i = 0; i < smpi_mpi_global->mpi_comm_world->size; i++) {
+                       if (SIMIX_process_is_suspended(smpi_global->sender_processes[i])) {
+                               SIMIX_process_resume(smpi_global->sender_processes[i]);
+                       }
+                       if (SIMIX_process_is_suspended(smpi_global->receiver_processes[i])) {
+                               SIMIX_process_resume(smpi_global->receiver_processes[i]);
+                       }
+               }
 
-               for (i = 0 ; i < smpi_mpi_comm_world.size; i++) {
-                       xbt_fifo_free(smpi_pending_send_requests[i]);
-                       SIMIX_mutex_destroy(smpi_pending_send_requests_mutex[i]);
-                       xbt_fifo_free(smpi_pending_recv_requests[i]);
-                       SIMIX_mutex_destroy(smpi_pending_recv_requests_mutex[i]);
-                       xbt_fifo_free(smpi_received_messages[i]);
-                       SIMIX_mutex_destroy(smpi_received_messages_mutex[i]);
+               // wait for senders/receivers to exit...
+               SIMIX_mutex_lock(smpi_global->start_stop_mutex);
+               if (smpi_global->ready_process_count > 0) {
+                       SIMIX_cond_wait(smpi_global->start_stop_cond, smpi_global->start_stop_mutex);
                }
+               SIMIX_mutex_unlock(smpi_global->start_stop_mutex);
+
+               SIMIX_mutex_destroy(smpi_mpi_global->mpi_comm_world->barrier_mutex);
+               SIMIX_cond_destroy(smpi_mpi_global->mpi_comm_world->barrier_cond);
+               xbt_free(smpi_mpi_global->mpi_comm_world->processes);
+               xbt_free(smpi_mpi_global->mpi_comm_world);
 
-               xbt_mallocator_free(smpi_request_mallocator);
-               xbt_mallocator_free(smpi_message_mallocator);
-               xbt_free(smpi_pending_send_requests);
-               xbt_free(smpi_pending_send_requests_mutex);
-               xbt_free(smpi_pending_recv_requests);
-               xbt_free(smpi_pending_recv_requests_mutex);
-               xbt_free(smpi_received_messages);
-               xbt_free(smpi_received_messages_mutex);
+               xbt_free(smpi_mpi_global->mpi_byte);
+               xbt_free(smpi_mpi_global->mpi_int);
+               xbt_free(smpi_mpi_global->mpi_double);
 
-               SIMIX_mutex_destroy(smpi_mpi_comm_world.barrier_mutex);
-               SIMIX_cond_destroy(smpi_mpi_comm_world.barrier_cond);
-               xbt_free(smpi_mpi_comm_world.processes);
+               xbt_free(smpi_mpi_global->mpi_land);
+               xbt_free(smpi_mpi_global->mpi_sum);
 
-               xbt_os_timer_free(smpi_timer);
+               xbt_free(smpi_mpi_global);
        }
 
 }
 
+// FIXME: could cause trouble with multithreaded procs on same host...
 void smpi_bench_begin()
 {
-       xbt_assert0(!smpi_benchmarking, "Already benchmarking");
-       smpi_benchmarking = 1;
-       xbt_os_timer_start(smpi_timer);
+       int rank = smpi_mpi_comm_world_rank_self();
+       SIMIX_mutex_lock(smpi_global->timers_mutexes[rank]);
+       xbt_os_timer_start(smpi_global->timers[rank]);
        return;
 }
 
 void smpi_bench_end()
 {
+       int rank = smpi_mpi_comm_world_rank_self();
        double duration;
        smx_host_t host;
        smx_action_t compute_action;
        smx_mutex_t mutex;
        smx_cond_t cond;
 
-       xbt_assert0(smpi_benchmarking, "Not benchmarking yet");
-       smpi_benchmarking = 0;
-       xbt_os_timer_stop(smpi_timer);
-       duration = xbt_os_timer_elapsed(smpi_timer);
-       host           = SIMIX_host_self();
+       xbt_os_timer_stop(smpi_global->timers[rank]);
+
+       duration       = xbt_os_timer_elapsed(smpi_global->timers[rank]);
+       SIMIX_mutex_unlock(smpi_global->timers_mutexes[rank]);
+
+       host           = smpi_mpi_global->mpi_comm_world->hosts[rank];
        compute_action = SIMIX_action_execute(host, "computation", duration * SMPI_DEFAULT_SPEED);
        mutex          = SIMIX_mutex_init();
        cond           = SIMIX_cond_init();
-       SIMIX_mutex_lock(mutex);
+
        SIMIX_register_condition_to_action(compute_action, cond);
        SIMIX_register_action_to_condition(compute_action, cond);
+       SIMIX_mutex_lock(mutex);
        SIMIX_cond_wait(cond, mutex);
        SIMIX_mutex_unlock(mutex);
+
        SIMIX_mutex_destroy(mutex);
        SIMIX_cond_destroy(cond);
+
        // FIXME: check for success/failure?
+
        return;
 }
 
 void smpi_barrier(smpi_mpi_communicator_t *comm) {
-       int i;
+
        SIMIX_mutex_lock(comm->barrier_mutex);
-       comm->barrier++;
-       if(i < comm->size) {
+       if(++comm->barrier_count < comm->size) {
                SIMIX_cond_wait(comm->barrier_cond, comm->barrier_mutex);
        } else {
-               comm->barrier = 0;
+               comm->barrier_count = 0;
                SIMIX_cond_broadcast(comm->barrier_cond);
        }
        SIMIX_mutex_unlock(comm->barrier_mutex);
+
+       return;
 }
 
+// FIXME: smarter algorithm...
 int smpi_comm_rank(smpi_mpi_communicator_t *comm, smx_host_t host)
 {
        int i;
@@ -563,7 +699,7 @@ int smpi_create_request(void *buf, int count, smpi_mpi_datatype_t *datatype,
        } else if (0 > tag) {
                retval = MPI_ERR_TAG;
        } else {
-               *request = xbt_mallocator_get(smpi_request_mallocator);
+               *request = xbt_mallocator_get(smpi_global->request_mallocator);
                (*request)->comm       = comm;
                (*request)->src        = src;
                (*request)->dst        = dst;
@@ -571,61 +707,60 @@ int smpi_create_request(void *buf, int count, smpi_mpi_datatype_t *datatype,
                (*request)->buf        = buf;
                (*request)->count      = count;
                (*request)->datatype   = datatype;
-               (*request)->completed  = 0;
-               (*request)->mutex      = SIMIX_mutex_init();
-               (*request)->cond       = SIMIX_cond_init();
-               (*request)->waitlist   = NULL;
        }
        return retval;
 }
 
 int smpi_isend(smpi_mpi_request_t *request)
 {
-       int rank = smpi_mpi_comm_rank_self(&smpi_mpi_comm_world);
+       int retval = MPI_SUCCESS;
+       int rank   = smpi_mpi_comm_world_rank_self();
 
-       SIMIX_mutex_lock(smpi_pending_send_requests_mutex[rank]);
-       xbt_fifo_push(smpi_pending_send_requests[rank], request);
-       SIMIX_mutex_unlock(smpi_pending_send_requests_mutex[rank]);
+       if (NULL != request) {
+               SIMIX_mutex_lock(smpi_global->pending_send_request_queues_mutexes[rank]);
+               xbt_fifo_push(smpi_global->pending_send_request_queues[rank], request);
+               SIMIX_mutex_unlock(smpi_global->pending_send_request_queues_mutexes[rank]);
+       }
 
-       if (MSG_process_is_suspended(smpi_sender_processes[rank])) {
-               MSG_process_resume(smpi_sender_processes[rank]);
+       if (SIMIX_process_is_suspended(smpi_global->sender_processes[rank])) {
+               SIMIX_process_resume(smpi_global->sender_processes[rank]);
        }
+
+       return retval;
 }
 
 int smpi_irecv(smpi_mpi_request_t *request)
 {
-       int rank = smpi_mpi_comm_rank_self(&smpi_mpi_comm_world);
+       int retval = MPI_SUCCESS;
+       int rank = smpi_mpi_comm_world_rank_self();
 
-       SIMIX_mutex_lock(smpi_pending_recv_requests_mutex[rank]);
-       xbt_fifo_push(smpi_pending_recv_requests[rank], request);
-       SIMIX_mutex_unlock(smpi_pending_recv_requests_mutex[rank]);
+       if (NULL != request) {
+               SIMIX_mutex_lock(smpi_global->pending_recv_request_queues_mutexes[rank]);
+               xbt_fifo_push(smpi_global->pending_recv_request_queues[rank], request);
+               SIMIX_mutex_unlock(smpi_global->pending_recv_request_queues_mutexes[rank]);
+       }
 
-       if (MSG_process_is_suspended(smpi_receiver_processes[rank])) {
-               MSG_process_resume(smpi_receiver_processes[rank]);
+       if (SIMIX_process_is_suspended(smpi_global->receiver_processes[rank])) {
+               SIMIX_process_resume(smpi_global->receiver_processes[rank]);
        }
+
+       return retval;
 }
 
 void smpi_wait(smpi_mpi_request_t *request, smpi_mpi_status_t *status)
 {
-       smx_process_t self;
+       smx_process_t self = SIMIX_process_self();
        int suspend = 0;
-       self = SIMIX_process_self();
 
        if (NULL != request) {
                SIMIX_mutex_lock(request->mutex);
                if (!request->completed) {
-                       xbt_fifo_push(request->waitlist, self);
-                       suspend = 1;
-               }
-               SIMIX_mutex_unlock(request->mutex);
-               if (suspend) {
-                       SIMIX_suspend(self);
+                       SIMIX_cond_wait(request->cond, request->mutex);
                }
-               if (NULL != status && MPI_STATUS_IGNORE != status) {
-                       SIMIX_mutex_lock(request->mutex);
+               if (NULL != status) {
                        status->MPI_SOURCE = request->src;
-                       SIMIX_mutex_unlock(request->mutex);
                }
+               SIMIX_mutex_unlock(request->mutex);
        }
 }
 
@@ -658,14 +793,18 @@ unsigned int smpi_sleep(unsigned int seconds)
        sleep_action = SIMIX_action_sleep(host, seconds);
        mutex        = SIMIX_mutex_init();
        cond         = SIMIX_cond_init();
-       SIMIX_mutex_lock(mutex);
+
        SIMIX_register_condition_to_action(sleep_action, cond);
        SIMIX_register_action_to_condition(sleep_action, cond);
+       SIMIX_mutex_lock(mutex);
        SIMIX_cond_wait(cond, mutex);
        SIMIX_mutex_unlock(mutex);
+
        SIMIX_mutex_destroy(mutex);
        SIMIX_cond_destroy(cond);
+
        // FIXME: check for success/failure?
+
        smpi_bench_begin();
        return 0;
 }
@@ -673,9 +812,9 @@ unsigned int smpi_sleep(unsigned int seconds)
 void smpi_exit(int status)
 {
        smpi_bench_end();
-       SIMIX_mutex_lock(smpi_running_hosts_mutex);
-       smpi_running_hosts--;
-       SIMIX_mutex_unlock(smpi_running_hosts_mutex);
+       SIMIX_mutex_lock(smpi_global->running_hosts_count_mutex);
+       smpi_global->running_hosts_count--;
+       SIMIX_mutex_unlock(smpi_global->running_hosts_count_mutex);
        SIMIX_process_kill(SIMIX_process_self());
        return;
 }