src/smpi/smpi_receiver.c

   1 #include "private.h"
   2
   3 int smpi_receiver(int argc, char **argv)
   4 {
   5         smx_process_t self;
   6         int index;
   7
   8         xbt_fifo_t request_queue;
   9         smx_mutex_t request_queue_mutex;
  10         xbt_fifo_t message_queue;
  11         smx_mutex_t message_queue_mutex;
  12
  13         int running_hosts_count;
  14
  15         smpi_mpi_request_t request;
  16         smpi_received_message_t message;
  17
  18         xbt_fifo_item_t request_item;
  19         xbt_fifo_item_t message_item;
  20
  21         self = SIMIX_process_self();
  22
  23         // make sure root is done before own initialization
  24         SIMIX_mutex_lock(smpi_global->start_stop_mutex);
  25         if (!smpi_global->root_ready) {
  26                 SIMIX_cond_wait(smpi_global->start_stop_cond, smpi_global->start_stop_mutex);
  27         }
  28         SIMIX_mutex_unlock(smpi_global->start_stop_mutex);
  29
  30         index = smpi_host_index();
  31
  32         request_queue       = smpi_global->pending_recv_request_queues[index];
  33         request_queue_mutex = smpi_global->pending_recv_request_queues_mutexes[index];
  34         message_queue       = smpi_global->received_message_queues[index];
  35         message_queue_mutex = smpi_global->received_message_queues_mutexes[index];
  36
  37         smpi_global->receiver_processes[index] = self;
  38
  39         // wait for all nodes to signal initializatin complete
  40         SIMIX_mutex_lock(smpi_global->start_stop_mutex);
  41         smpi_global->ready_process_count++;
  42         if (smpi_global->ready_process_count < 3 * smpi_global->host_count) {
  43                 SIMIX_cond_wait(smpi_global->start_stop_cond, smpi_global->start_stop_mutex);
  44         } else {
  45                 SIMIX_cond_broadcast(smpi_global->start_stop_cond);
  46         }
  47         SIMIX_mutex_unlock(smpi_global->start_stop_mutex);
  48
  49         do {
  50                 request = NULL;
  51                 message = NULL;
  52
  53                 // FIXME: better algorithm, maybe some kind of balanced tree? or a heap?
  54
  55                 // FIXME: not the best way to request multiple locks...
  56                 SIMIX_mutex_lock(request_queue_mutex);
  57                 SIMIX_mutex_lock(message_queue_mutex);
  58                 for (request_item = xbt_fifo_get_first_item(request_queue);
  59                         NULL != request_item;
  60                         request_item = xbt_fifo_get_next_item(request_item)) {
  61                         request = xbt_fifo_get_item_content(request_item);
  62                         for (message_item = xbt_fifo_get_first_item(message_queue);
  63                                 NULL != message_item;
  64                                 message_item = xbt_fifo_get_next_item(message_item)) {
  65                                 message = xbt_fifo_get_item_content(message_item);
  66                                 if (request->comm == message->comm &&
  67                                    (MPI_ANY_SOURCE == request->src || request->src == message->src) &&
  68                                    (MPI_ANY_TAG == request->tag || request->tag == message->tag)) {
  69                                         xbt_fifo_remove_item(request_queue, request_item);
  70                                         xbt_fifo_remove_item(message_queue, message_item);
  71                                         goto stopsearch;
  72                                 }
  73                         }
  74                 }
  75 stopsearch:
  76                 SIMIX_mutex_unlock(message_queue_mutex);
  77                 SIMIX_mutex_unlock(request_queue_mutex);
  78
  79                 if (NULL == request || NULL == message) {
  80                         SIMIX_process_suspend(self);
  81                 } else {
  82
  83                         SIMIX_mutex_lock(request->mutex);
  84                         memcpy(request->buf, message->buf, request->datatype->size * request->count);
  85                         request->src = message->src;
  86                         request->data = message->data;
  87                         request->forward = message->forward;
  88
  89                         if (0 == request->forward) {
  90                                 request->completed = 1;
  91                                 SIMIX_cond_broadcast(request->cond);
  92                         } else {
  93                                 request->src = request->comm->index_to_rank_map[index];
  94                                 request->dst = (request->src + 1) % request->comm->size;
  95                                 smpi_mpi_isend(request);
  96                         }
  97
  98                         SIMIX_mutex_unlock(request->mutex);
  99
 100                         xbt_free(message->buf);
 101                         xbt_mallocator_release(smpi_global->message_mallocator, message);
 102
 103                 }
 104
 105                 SIMIX_mutex_lock(smpi_global->running_hosts_count_mutex);
 106                 running_hosts_count = smpi_global->running_hosts_count;
 107                 SIMIX_mutex_unlock(smpi_global->running_hosts_count_mutex);
 108
 109         } while (0 < running_hosts_count);
 110
 111         return 0;
 112 }