torus.c 18 KB
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#include "codes/torus.h"

/* setup the torus model */
static void torus_setup(const void* net_params)
{
    int i;
    torus_param* t_param = (torus_param*)net_params;
    n_dims = t_param->n_dims;
    link_bandwidth = t_param->link_bandwidth;
    buffer_size = t_param->buffer_size;
    num_vc = t_param->num_vc;
    
    head_delay = (1 / link_bandwidth) * CHUNK_SIZE;
    credit_delay = (1 / link_bandwidth) * 8;
    dim_length = malloc(n_dims * sizeof(int));
    factor = malloc(n_dims * sizeof(int));
    half_length = malloc(n_dims * sizeof(int));
    for(i = 0; i < n_dims; i++)
       dim_length[i] = t_param->dim_length[i]; /* TODO, read comma separated values from files */
}

static void torus_packet_event_rc(tw_lp *sender)
{
  codes_local_latency_reverse(sender);
  return;
}

/* torus mode packet event */
static void torus_packet_event(char* category, tw_lpid final_dest_lp, int packet_size, int remote_event_size, const void* remote_event, int self_event_size, const void* self_event, tw_lp *sender, int is_last_pckt)
{
    tw_event * e_new;
    tw_stime xfer_to_nic_time;
    nodes_message * msg;
    tw_lpid local_nic_id, dest_nic_id;
    char* tmp_ptr;
    char lp_type_name[MAX_NAME_LENGTH], lp_group_name[MAX_NAME_LENGTH];
   
    int mapping_grp_id, mapping_rep_id, mapping_type_id, mapping_offset;
    codes_mapping_get_lp_info(sender->gid, lp_group_name, &mapping_grp_id, &mapping_type_id, lp_type_name, &mapping_rep_id, &mapping_offset);
    codes_mapping_get_lp_id("MODELNET_GRP", "modelnet_torus", mapping_rep_id, mapping_offset, &local_nic_id);

    codes_mapping_get_lp_info(final_dest_lp, lp_group_name, &mapping_grp_id, &mapping_type_id, lp_type_name, &mapping_rep_id, &mapping_offset);
    codes_mapping_get_lp_id("MODELNET_GRP", "modelnet_torus", mapping_rep_id, mapping_offset, &dest_nic_id);

    /* TODO: Should send the packets in correct sequence. Currently the last packet is being sent first due to codes_local_latency offset. */
    xfer_to_nic_time = 0.01 + codes_local_latency(sender); /* Throws an error of found last KP time > current event time otherwise */
    e_new = codes_event_new(local_nic_id, xfer_to_nic_time, sender);
    msg = tw_event_data(e_new);
    strcpy(msg->category, category);
    msg->final_dest_gid = final_dest_lp;
    msg->dest_lp = dest_nic_id;
    msg->sender_lp=sender->gid;
    msg->packet_size = packet_size;
    msg->remote_event_size_bytes = 0;
    msg->local_event_size_bytes = 0;
    msg->type = GENERATE;

    if(is_last_pckt) /* Its the last packet so pass in remote event information*/
     {
        tmp_ptr = (char*)msg;
        tmp_ptr += torus_get_msg_sz();
	if(remote_event_size > 0)
	 {
	    msg->remote_event_size_bytes = remote_event_size;
	    memcpy(tmp_ptr, remote_event, remote_event_size);
	    tmp_ptr += remote_event_size;
         }
	if(self_event_size > 0)
	{
	   msg->local_event_size_bytes = self_event_size;
	   memcpy(tmp_ptr, self_event, self_event_size);
	   tmp_ptr += self_event_size;
	}
     }
   //printf("\n torus remote event %d local event %d last packet %d %lf ", msg->remote_event_size_bytes, msg->local_event_size_bytes, is_last_pckt, xfer_to_nic_time);
    tw_event_send(e_new);
}
/*Initialize the torus model, this initialization part is borrowed from Ning's torus model */
static void torus_init( nodes_state * s, 
	   tw_lp * lp )
{
    int i, j;
    int dim_N[ n_dims + 1 ];

    codes_mapping_get_lp_info(lp->gid, grp_name, &grp_id, &lp_type_id, type_name, &rep_id, &offset);
    dim_N[ 0 ]=rep_id + offset;

    s->neighbour_minus_lpID = (int*)malloc(n_dims * sizeof(int));
    s->neighbour_plus_lpID = (int*)malloc(n_dims * sizeof(int));
    s->dim_position = (int*)malloc(n_dims * sizeof(int));
    s->buffer = (int**)malloc(2*n_dims * sizeof(int*));
    s->next_link_available_time = (tw_stime**)malloc(2*n_dims * sizeof(tw_stime*));
    s->next_credit_available_time = (tw_stime**)malloc(2*n_dims * sizeof(tw_stime*));
    s->next_flit_generate_time = (tw_stime**)malloc(2*n_dims*sizeof(tw_stime*));

    for(i=0; i < 2*n_dims; i++)
    {
	s->buffer[i] = (int*)malloc(num_vc * sizeof(int));
	s->next_link_available_time[i] = (tw_stime*)malloc(num_vc * sizeof(tw_stime));
	s->next_credit_available_time[i] = (tw_stime*)malloc(num_vc * sizeof(tw_stime));
	s->next_flit_generate_time[i] = (tw_stime*)malloc(num_vc * sizeof(tw_stime));
    }

    //printf("\n LP ID %d ", (int)lp->gid);
  // calculate my torus co-ordinates
  for ( i=0; i < n_dims; i++ ) 
    {
      s->dim_position[ i ] = dim_N[ i ]%dim_length[ i ];
      //printf(" dim position %d ", s->dim_position[i]);
      dim_N[ i + 1 ] = ( dim_N[ i ] - s->dim_position[ i ] )/dim_length[ i ];

      half_length[ i ] = dim_length[ i ] / 2;
    }
   //printf("\n");

  factor[ 0 ] = 1;
  for ( i=1; i < n_dims; i++ )
    {
      factor[ i ] = 1;
      for ( j = 0; j < i; j++ )
        factor[ i ] *= dim_length[ j ];
    }
  int temp_dim_pos[ n_dims ];
  for ( i = 0; i < n_dims; i++ )
    temp_dim_pos[ i ] = s->dim_position[ i ];

  tw_lpid neighbor_id;
  // calculate minus neighbour's lpID
  for ( j = 0; j < n_dims; j++ )
    {
      temp_dim_pos[ j ] = (s->dim_position[ j ] -1 + dim_length[ j ]) % dim_length[ j ];

      s->neighbour_minus_lpID[ j ] = 0;
      
      for ( i = 0; i < n_dims; i++ )
        s->neighbour_minus_lpID[ j ] += factor[ i ] * temp_dim_pos[ i ];
      
      codes_mapping_get_lp_id("MODELNET_GRP", "modelnet_torus", s->neighbour_minus_lpID[ j ], 0, &neighbor_id);
      //printf("\n neighbor %d lp id %d ", (int)s->neighbour_minus_lpID[ j ], (int)neighbor_id);
      
      temp_dim_pos[ j ] = s->dim_position[ j ];
    }
  // calculate plus neighbour's lpID
  for ( j = 0; j < n_dims; j++ )
    {
      temp_dim_pos[ j ] = ( s->dim_position[ j ] + 1 + dim_length[ j ]) % dim_length[ j ];

      s->neighbour_plus_lpID[ j ] = 0;
      
      for ( i = 0; i < n_dims; i++ )
        s->neighbour_plus_lpID[ j ] += factor[ i ] * temp_dim_pos[ i ];

      codes_mapping_get_lp_id("MODELNET_GRP", "modelnet_torus", s->neighbour_plus_lpID[ j ], 0, &neighbor_id);
      //printf("\n neighbor %d lp id %d ", (int)s->neighbour_plus_lpID[ j ], (int)neighbor_id);
      
      temp_dim_pos[ j ] = s->dim_position[ j ];
    }

  //printf("\n");
  for( j=0; j < 2 * n_dims; j++ )
   {
    for( i = 0; i < num_vc; i++ )
     {
       s->buffer[ j ][ i ] = 0; 
       s->next_link_available_time[ j ][ i ] = 0.0;
       s->next_credit_available_time[j][i] = 0.0; 
     }
   }
  // record LP time
    s->packet_counter = 0;
}

static int torus_get_msg_sz(void)
{
   return sizeof(nodes_message);
}

/*Returns the next neighbor to which the packet should be routed by using DOR (Taken from Ning's code of the torus model)*/
static void dimension_order_routing( nodes_state * s,
			     tw_lpid * dst_lp, 
			     int * dim, 
			     int * dir )
{
  int dim_N[n_dims], 
      dest[n_dims],
      i,
      dest_id=0;

  codes_mapping_get_lp_info(*dst_lp, grp_name, &grp_id, &lp_type_id, type_name, &rep_id, &offset);
  dim_N[ 0 ]=rep_id + offset;

  // find destination dimensions using destination LP ID 
  for ( i = 0; i < n_dims; i++ )
    {
      dest[ i ] = dim_N[ i ] % dim_length[ i ];
      dim_N[ i + 1 ] = ( dim_N[ i ] - dest[ i ] ) / dim_length[ i ];
    }

  for( i = 0; i < n_dims; i++ )
    {
      if ( s->dim_position[ i ] - dest[ i ] > half_length[ i ] )
	{
	  dest_id = s->neighbour_plus_lpID[ i ];
	  *dim = i;
	  *dir = 1;
	  break;
	}
      if ( s->dim_position[ i ] - dest[ i ] < -half_length[ i ] )
	{
	  dest_id = s->neighbour_minus_lpID[ i ];
	  *dim = i;
	  *dir = 0;
	  break;
	}
      if ( ( s->dim_position[ i ] - dest[ i ] <= half_length[ i ] ) && ( s->dim_position[ i ] - dest[ i ] > 0 ) )
	{
	  dest_id = s->neighbour_minus_lpID[ i ];
	  *dim = i;
	  *dir = 0;
	  break;
	}
      if (( s->dim_position[ i ] - dest[ i ] >= -half_length[ i ] ) && ( s->dim_position[ i ] - dest[ i ] < 0) )
	{
	  dest_id = s->neighbour_plus_lpID[ i ];
	  *dim = i;
	  *dir = 1;
	  break;
	}
    }
  codes_mapping_get_lp_id("MODELNET_GRP", "modelnet_torus", dest_id, 0, dst_lp);
}
/*Generates a packet. If there are two buffer slots available, then the packet is 
injected in the network. Else, the packet is placed in the injection queue */
static void packet_generate( nodes_state * s, 
		tw_bf * bf, 
		nodes_message * msg, 
		tw_lp * lp )
{
//    printf("\n msg local event size %d remote event size %d ", msg->local_event_size_bytes, msg->remote_event_size_bytes);
    int j, tmp_dir=-1, tmp_dim=-1;
    tw_stime ts;

//    event triggered when packet head is sent
    tw_event * e_h;
    nodes_message *m;

    tw_lpid dst_lp = msg->dest_lp; 
    dimension_order_routing( s, &dst_lp, &tmp_dim, &tmp_dir );

    msg->saved_src_dim = tmp_dim;
    msg->saved_src_dir = tmp_dir;

    //msg->saved_available_time = s->next_flit_generate_time[(2*tmp_dim) + tmp_dir][0];
    msg->travel_start_time = tw_now(lp);
    msg->packet_ID = lp->gid + g_tw_nlp * s->packet_counter;

    num_chunks = msg->packet_size/CHUNK_SIZE;
    s->packet_counter++;

    if(msg->packet_ID == TRACE)
	    printf("\n packet generated %lld at lp %d dest %d final dest %d", msg->packet_ID, (int)lp->gid, (int)dst_lp, (int)msg->dest_lp);
    for(j = 0; j < num_chunks; j++)
    { 
     if(s->buffer[ tmp_dir + ( tmp_dim * 2 ) ][ 0 ] < buffer_size)
      {
       ts = j + tw_rand_exponential(lp->rng, MEAN_INTERVAL/200);
       //s->next_flit_generate_time[(2*tmp_dim) + tmp_dir][0] = max(s->next_flit_generate_time[(2*tmp_dim) + tmp_dir][0], tw_now(lp));
       //s->next_flit_generate_time[(2*tmp_dim) + tmp_dir][0] += ts;
       //e_h = tw_event_new( lp->gid, s->next_flit_generate_time[(2*tmp_dim) + tmp_dir][0] - tw_now(lp), lp);
       e_h = tw_event_new(lp->gid, ts, lp);
       msg->source_direction = tmp_dir;
       msg->source_dim = tmp_dim;

       m = tw_event_data( e_h );
       memcpy(m, msg, torus_get_msg_sz() + msg->local_event_size_bytes + msg->remote_event_size_bytes);
       m->next_stop = dst_lp;
       m->chunk_id = j;

      // find destination dimensions using destination LP ID 
       m->my_N_hop = 0;
        // Send the packet out
       m->type = SEND;
       m->source_direction = tmp_dir;
       m->source_dim = tmp_dim;
       tw_event_send(e_h);
      }
      else 
       {
   printf("\n %d Packet queued in line increase buffer space, dir %d dim %d buffer space %d dest LP %d ", (int)lp->gid, tmp_dir, tmp_dim, s->buffer[ tmp_dir + ( tmp_dim * 2 ) ][ 0 ], (int)msg->dest_lp);
       }
   }
}
/*Sends a 8-byte credit back to the torus node LP that sent the message */
static void credit_send( nodes_state * s, 
	    tw_bf * bf, 
	    tw_lp * lp, 
	    nodes_message * msg)
{
#if DEBUG
//if(lp->gid == TRACK_LP)
//	printf("\n (%lf) sending credit tmp_dir %d tmp_dim %d %lf ", tw_now(lp), msg->source_direction, msg->source_dim, credit_delay );
#endif
    bf->c1 = 0;
    tw_event * buf_e;
    nodes_message *m;
    tw_stime ts;
    int src_dir = msg->source_direction;
    int src_dim = msg->source_dim;

    msg->saved_available_time = s->next_credit_available_time[(2 * src_dim) + src_dir][0];
    s->next_credit_available_time[(2 * src_dim) + src_dir][0] = max(s->next_credit_available_time[(2 * src_dim) + src_dir][0], tw_now(lp));
    ts =  credit_delay + tw_rand_exponential(lp->rng, credit_delay/1000);
    s->next_credit_available_time[(2 * src_dim) + src_dir][0] += ts;

    buf_e = tw_event_new( msg->sender_lp, s->next_credit_available_time[(2 * src_dim) + src_dir][0] - tw_now(lp), lp);
    m = tw_event_data(buf_e);
    m->source_direction = msg->source_direction;
    m->source_dim = msg->source_dim;

    m->type = CREDIT;
    tw_event_send( buf_e );

}
// send a packet from one torus node to another torus node
// A packet can be up to 256 bytes on BG/L and BG/P and up to 512 bytes on BG/Q
static void packet_send( nodes_state * s, 
	         tw_bf * bf, 
		 nodes_message * msg, 
		 tw_lp * lp )
{ 
    bf->c2 = 0;
    bf->c1 = 0;
    int tmp_dir, tmp_dim;
    tw_stime ts;
    tw_event *e;
    nodes_message *m;
    tw_lpid dst_lp = msg->dest_lp;
    dimension_order_routing( s, &dst_lp, &tmp_dim, &tmp_dir );     

    if(s->buffer[ tmp_dir + ( tmp_dim * 2 ) ][ 0 ] < buffer_size)
    {
       bf->c2 = 1;
       msg->saved_src_dir = tmp_dir;
       msg->saved_src_dim = tmp_dim;
       ts = tw_rand_exponential( lp->rng, ( double )head_delay/200 )+ head_delay;

//    For reverse computation 
      msg->saved_available_time = s->next_link_available_time[tmp_dir + ( tmp_dim * 2 )][0];

      s->next_link_available_time[tmp_dir + ( tmp_dim * 2 )][0] = max( s->next_link_available_time[ tmp_dir + ( tmp_dim * 2 )][0], tw_now(lp) );
      s->next_link_available_time[tmp_dir + ( tmp_dim * 2 )][0] += ts;
    
      e = tw_event_new( dst_lp, s->next_link_available_time[tmp_dir + ( tmp_dim * 2 )][0] - tw_now(lp), lp );
      m = tw_event_data( e );
      memcpy(m, msg, torus_get_msg_sz() + msg->remote_event_size_bytes);
      m->type = ARRIVAL;

      if(msg->packet_ID == TRACE)
        printf("\n lp %d packet %lld flit id %d being sent to %d after time %lf ", (int) lp->gid, msg->packet_ID, msg->chunk_id, (int)dst_lp, s->next_link_available_time[tmp_dir + ( tmp_dim * 2 )][0] - tw_now(lp)); 
      //Carry on the message info
      m->source_dim = tmp_dim;
      m->source_direction = tmp_dir;
      m->next_stop = dst_lp;
      m->sender_lp = lp->gid;
      m->local_event_size_bytes = 0; /* We just deliver the local event here */

      tw_event_send( e );

      s->buffer[ tmp_dir + ( tmp_dim * 2 ) ][ 0 ]++;
    
      if(msg->chunk_id == num_chunks - 1)
      {
        bf->c1 = 1;
	if(msg->local_event_size_bytes > 0)
	{
          tw_event* e_new;
	  nodes_message* m_new;
	  char* local_event;
	  ts = (1/link_bandwidth) * msg->local_event_size_bytes;
	  e_new = codes_event_new(msg->sender_lp, ts, lp);
	  m_new = tw_event_data(e_new);
	  local_event = (char*)msg;
	  local_event += torus_get_msg_sz() + msg->remote_event_size_bytes;
	  memcpy(m_new, local_event, msg->local_event_size_bytes);
	  tw_event_send(e_new);
	}
     }
  } // end if
    else
	    printf("\n buffer overflown ");
}

/*Processes the packet after it arrives from the neighboring torus node */
static void packet_arrive( nodes_state * s, 
		    tw_bf * bf, 
		    nodes_message * msg, 
		    tw_lp * lp )
{
  bf->c2 = 0;
  tw_event *e;
  tw_stime ts;
  nodes_message *m;

  credit_send( s, bf, lp, msg); // Commented on May 22nd to check if the credit needs to be sent from the final destination or not
  
  msg->my_N_hop++;
  ts = 0.1 + tw_rand_exponential(lp->rng, MEAN_INTERVAL/200);
  if(msg->packet_ID == TRACE)
	  printf("\n packet arrived at lp %d final dest %d ", (int)lp->gid, (int)msg->dest_lp);
  if( lp->gid == msg->dest_lp )
    {   
        if( msg->chunk_id == num_chunks - 1 )    
        {
	    bf->c2 = 1;
	    N_finished_packets++;
	    total_time += tw_now( lp ) - msg->travel_start_time;
	    total_hops += msg->my_N_hop;

	    if (max_latency < tw_now( lp ) - msg->travel_start_time) {
		  bf->c3 = 1;
		  msg->saved_available_time = max_latency;
	          max_latency=tw_now( lp ) - msg->travel_start_time;
     		}
	    // Trigger an event on receiving server
	    if(msg->remote_event_size_bytes)
	    {
	       ts = (1/link_bandwidth) * msg->remote_event_size_bytes;
	       if(msg->packet_ID == TRACE)
		     printf("\n lp %d Sending final message after %lf ",(int)lp->gid, ts);
	       e = codes_event_new(msg->final_dest_gid, ts, lp);
	       m = tw_event_data(e);
	       char* tmp_ptr = (char*)msg;
	       tmp_ptr += torus_get_msg_sz();
	       memcpy(m, tmp_ptr, msg->remote_event_size_bytes);
	       tw_event_send(e);
	    }
       }
    }
  else
    {
      e = tw_event_new(lp->gid, ts , lp);
      m = tw_event_data( e );
      memcpy(m, msg, torus_get_msg_sz() + msg->remote_event_size_bytes);
      m->type = SEND;
      m->next_stop = -1;
      tw_event_send(e);
   }
}

void
final( nodes_state * s, tw_lp * lp )
{
  free(s->next_link_available_time);
  free(s->next_credit_available_time);
  free(s->next_flit_generate_time);
  free(s->buffer); 
}

static void packet_buffer_process( nodes_state * s, tw_bf * bf, nodes_message * msg, tw_lp * lp )
{
   s->buffer[ msg->source_direction + ( msg->source_dim * 2 ) ][  0 ]--;
}
static void node_rc_handler(nodes_state * s, tw_bf * bf, nodes_message * msg, tw_lp * lp)
{
  switch(msg->type)
    {
       case GENERATE:
		   {
		     s->packet_counter--;
		     int i;//, saved_dim, saved_dir;
	 	     //saved_dim = msg->saved_src_dim;
		     //saved_dir = msg->saved_src_dir;

		     //s->next_flit_generate_time[(saved_dim * 2) + saved_dir][0] = msg->saved_available_time;
		     for(i=0; i < num_chunks; i++)
  		        tw_rand_reverse_unif(lp->rng);	
		   }
	break;
	
	case ARRIVAL:
		   {
 		    msg->my_N_hop--;
  		    tw_rand_reverse_unif(lp->rng);
		    tw_rand_reverse_unif(lp->rng);
		    int next_dim = msg->source_dim;
		    int next_dir = msg->source_direction;

		    s->next_credit_available_time[next_dir + ( next_dim * 2 )][0] = msg->saved_available_time;
		    if(bf->c2)
		    {
		       N_finished_packets--;
		       total_time -= tw_now( lp ) - msg->travel_start_time;
		       total_hops -= msg->my_N_hop;
		    }
		   }
	break;	

	case SEND:
		 {
		    if(bf->c2)
		     {
                        int next_dim = msg->saved_src_dim;
			int next_dir = msg->saved_src_dir;
			s->next_link_available_time[next_dir + ( next_dim * 2 )][0] = msg->saved_available_time;
			s->buffer[ next_dir + ( next_dim * 2 ) ][ 0 ] --;
	                tw_rand_reverse_unif(lp->rng);
		    }
		 }
	break;

       case CREDIT:
		{
		  s->buffer[ msg->source_direction + ( msg->source_dim * 2 ) ][  0 ]++;
              }
       break;
     }
}

static void event_handler(nodes_state * s, tw_bf * bf, nodes_message * msg, tw_lp * lp)
{
 *(int *) bf = (int) 0;
 switch(msg->type)
 {
  case GENERATE:
    packet_generate(s,bf,msg,lp);
  break;
  case ARRIVAL:
    packet_arrive(s,bf,msg,lp);
  break;
  case SEND:
   packet_send(s,bf,msg,lp);
  break;
  case CREDIT:
    packet_buffer_process(s,bf,msg,lp);
   break;
  DEFAULT:
	printf("\n Being sent to wrong LP");
  break;
 }
}

tw_lptype torus_lp =
{
  (init_f) torus_init,
  (event_f) event_handler,
  (revent_f) node_rc_handler,
  (final_f) final,
  (map_f) codes_mapping,
  sizeof(nodes_state),
};

static const tw_lptype* torus_get_lp_type(void)
{
   return(&torus_lp); 
}