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