src/smpi/smpi_receiver.c

   1 #include "private.h"
   2
   3 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(smpi_receiver, smpi, "Logging specific to SMPI (receiver)");
   4
   5 int smpi_receiver(int argc, char **argv)
   6 {
   7         smx_process_t self;
   8         int index;
   9
  10         xbt_fifo_t request_queue;
  11         smx_mutex_t request_queue_mutex;
  12         xbt_fifo_t message_queue;
  13         smx_mutex_t message_queue_mutex;
  14
  15         int running_hosts_count;
  16
  17         smpi_mpi_request_t request;
  18         smpi_received_message_t message;
  19
  20         xbt_fifo_item_t request_item;
  21         xbt_fifo_item_t message_item;
  22
  23         self = SIMIX_process_self();
  24
  25         // make sure root is done before own initialization
  26         SIMIX_mutex_lock(smpi_global->start_stop_mutex);
  27         while (!smpi_global->root_ready) {
  28                 SIMIX_cond_wait(smpi_global->start_stop_cond, smpi_global->start_stop_mutex);
  29         }
  30         SIMIX_mutex_unlock(smpi_global->start_stop_mutex);
  31
  32         index = smpi_host_index();
  33
  34         request_queue       = smpi_global->pending_recv_request_queues[index];
  35         request_queue_mutex = smpi_global->pending_recv_request_queues_mutexes[index];
  36         message_queue       = smpi_global->received_message_queues[index];
  37         message_queue_mutex = smpi_global->received_message_queues_mutexes[index];
  38
  39         smpi_global->receiver_processes[index] = 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 * smpi_global->host_count) {
  45                 SIMIX_cond_broadcast(smpi_global->start_stop_cond);
  46         }
  47         while (smpi_global->ready_process_count < 3 * smpi_global->host_count) {
  48                 SIMIX_cond_wait(smpi_global->start_stop_cond, smpi_global->start_stop_mutex);
  49         }
  50         SIMIX_mutex_unlock(smpi_global->start_stop_mutex);
  51
  52         do {
  53                 request = NULL;
  54                 message = NULL;
  55
  56                 // FIXME: better algorithm, maybe some kind of balanced tree? or a heap?
  57
  58                 // FIXME: not the best way to request multiple locks...
  59                 SIMIX_mutex_lock(request_queue_mutex);
  60                 SIMIX_mutex_lock(message_queue_mutex);
  61                 for (request_item = xbt_fifo_get_first_item(request_queue);
  62                         NULL != request_item;
  63                         request_item = xbt_fifo_get_next_item(request_item)) {
  64                         request = xbt_fifo_get_item_content(request_item);
  65                         for (message_item = xbt_fifo_get_first_item(message_queue);
  66                                 NULL != message_item;
  67                                 message_item = xbt_fifo_get_next_item(message_item)) {
  68                                 message = xbt_fifo_get_item_content(message_item);
  69                                 if (request->comm == message->comm &&
  70                                    (MPI_ANY_SOURCE == request->src || request->src == message->src) &&
  71                                    (MPI_ANY_TAG == request->tag || request->tag == message->tag)) {
  72                                         xbt_fifo_remove_item(request_queue, request_item);
  73                                         xbt_fifo_remove_item(message_queue, message_item);
  74                                         goto stopsearch;
  75                                 }
  76                         }
  77                 }
  78 stopsearch:
  79                 SIMIX_mutex_unlock(message_queue_mutex);
  80                 SIMIX_mutex_unlock(request_queue_mutex);
  81
  82                 if (NULL == request || NULL == message) {
  83                         SIMIX_process_suspend(self);
  84                 } else {
  85
  86                         SIMIX_mutex_lock(request->mutex);
  87                         memcpy(request->buf, message->buf, request->datatype->size * request->count);
  88                         request->src = message->src;
  89                         request->data = message->data;
  90                         request->forward = message->forward;
  91
  92                         if (0 == request->forward) {
  93                                 request->completed = 1;
  94                                 SIMIX_cond_broadcast(request->cond);
  95                         } else {
  96                                 request->src = request->comm->index_to_rank_map[index];
  97                                 request->dst = (request->src + 1) % request->comm->size;
  98                                 smpi_mpi_isend(request);
  99                         }
 100
 101                         SIMIX_mutex_unlock(request->mutex);
 102
 103                         xbt_free(message->buf);
 104                         xbt_mallocator_release(smpi_global->message_mallocator, message);
 105
 106                 }
 107
 108                 SIMIX_mutex_lock(smpi_global->running_hosts_count_mutex);
 109                 running_hosts_count = smpi_global->running_hosts_count;
 110                 SIMIX_mutex_unlock(smpi_global->running_hosts_count_mutex);
 111
 112         } while (0 < running_hosts_count);
 113
 114         return 0;
 115 }