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/*
 * Copyright (C) 2013 University of Chicago.
 * See COPYRIGHT notice in top-level directory.
 *
 */

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#include <ross.h>
#include <assert.h>
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#include <string.h>
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#include "codes/lp-io.h"
#include "codes/codes_mapping.h"
#include "codes/codes.h"
#include "codes/model-net.h"
#include "codes/model-net-method.h"
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#include "codes/model-net-lp.h"
#include "codes/net/torus.h"
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#define CHUNK_SIZE 32
#define DEBUG 1
#define MEAN_INTERVAL 100
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#define TRACE -1
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/* collective specific parameters */
#define TREE_DEGREE 4
#define LEVEL_DELAY 1000
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#define TORUS_COLLECTIVE_DEBUG 0
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#define NUM_COLLECTIVES  1
#define COLLECTIVE_COMPUTATION_DELAY 5700
#define TORUS_FAN_OUT_DELAY 20.0

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#define LP_CONFIG_NM (model_net_lp_config_names[TORUS])
#define LP_METHOD_NM (model_net_method_names[TORUS])

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static double maxd(double a, double b) { return a < b ? b : a; }

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/* Torus network model implementation of codes, implements the modelnet API */

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typedef struct torus_param torus_param;
struct torus_param
{
    int n_dims; /*Dimension of the torus network, 5-D, 7-D or any other*/
    int* dim_length; /*Length of each torus dimension*/
    double link_bandwidth;/* bandwidth for each torus link */
    int buffer_size; /* number of buffer slots for each vc in flits*/
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    //int num_net_traces; /* number of network traces to be mapped on torus */
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    int num_vc; /* number of virtual channels for each torus link */
    float mean_process;/* mean process time for each flit  */
    int chunk_size; /* chunk is the smallest unit--default set to 32 */

    /* "derived" torus parameters */

    /* factor, used in torus coordinate calculation */
    int * factor;
    /* half length of each dimension, used in torus coordinates calculation */
    int * half_length;

    double head_delay;
    double credit_delay;
};
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/* codes mapping group name, lp type name */
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static char grp_name[MAX_NAME_LENGTH];
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/* codes mapping group id, lp type id, repetition id and offset */
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int mapping_grp_id, mapping_rep_id, mapping_type_id, mapping_offset;
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/* for calculating torus model statistics, average and maximum travel time of a packet */
static tw_stime         total_time = 0;
static tw_stime         max_latency = 0;
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static tw_stime         max_collective = 0;
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/* number of finished packets on each PE */
static long long       N_finished_packets = 0;
/* total number of hops traversed by a message on each PE */
static long long       total_hops = 0;

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/* annotation-specific parameters (unannotated entry occurs at the 
 * last index) */
static uint64_t                  num_params = 0;
static torus_param             * all_params = NULL;
static const config_anno_map_t * anno_map   = NULL;
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typedef struct nodes_state nodes_state;

/* state of a torus node */
struct nodes_state
{
  /* counts the number of packets sent from this compute node */
  unsigned long long packet_counter;            
  /* availability time of each torus link */
  tw_stime** next_link_available_time; 
  /* availability of each torus credit link */
  tw_stime** next_credit_available_time;
  /* next flit generate time */
  tw_stime** next_flit_generate_time;
  /* buffer size for each torus virtual channel */
  int** buffer;
  /* coordinates of the current torus node */
  int* dim_position;
  /* neighbor LP ids for this torus node */
  int* neighbour_minus_lpID;
  int* neighbour_plus_lpID;

  /* records torus statistics for this LP having different communication categories */
  struct mn_stats torus_stats_array[CATEGORY_MAX];
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   /* for collective operations */

  /* collective init time */
  tw_stime collective_init_time;

  /* node ID in the tree */ 
   tw_lpid node_id;

   /* messages sent & received in collectives may get interchanged several times so we have to save the 
     origin server information in the node's state */
   tw_lpid origin_svr; 
  
  /* parent node ID of the current node */
   tw_lpid parent_node_id;
   /* array of children to be allocated in terminal_init*/
   tw_lpid* children;

   /* children of a node can be less than or equal to the tree degree */
   int num_children;

   short is_root;
   short is_leaf;

   /* to maintain a count of child nodes that have fanned in at the parent during the collective
      fan-in phase*/
   int num_fan_nodes;
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   /* LPs annotation */
   const char * anno;
   /* LPs configuration */
   const torus_param * params;
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};

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static void torus_read_config(
        const char         * anno,
        torus_param        * params){
    char dim_length_str[MAX_NAME_LENGTH];
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    int i;
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    // shorthand
    torus_param *p = params;

    configuration_get_value_int(&config, "PARAMS", "n_dims", anno, &p->n_dims);
    if(!p->n_dims) {
        p->n_dims = 4; /* a 4-D torus */
        fprintf(stderr, 
                "Warning: Number of dimensions not specified, setting to %d\n",
                p->n_dims);
    }

    configuration_get_value_double(&config, "PARAMS", "link_bandwidth", anno,
            &p->link_bandwidth);
    if(!p->link_bandwidth) {
        p->link_bandwidth = 2.0; /*default bg/q configuration */
        fprintf(stderr, "Link bandwidth not specified, setting to %lf\n",
                p->link_bandwidth);
    }

    configuration_get_value_int(&config, "PARAMS", "buffer_size", anno, &p->buffer_size);
    if(!p->buffer_size) {
        p->buffer_size = 2048;
        fprintf(stderr, "Buffer size not specified, setting to %d",
                p->buffer_size);
    }

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    configuration_get_value_int(&config, "PARAMS", "chunk_size", anno, &p->chunk_size);
    if(!p->chunk_size) {
        p->chunk_size = 32;
        fprintf(stderr, "Warning: Chunk size not specified, setting to %d\n",
                p->chunk_size);
    }
    configuration_get_value_int(&config, "PARAMS", "num_vc", anno, &p->num_vc);
    if(!p->num_vc) {
        /* by default, we have one for taking packets,
         * another for taking credit*/
        p->num_vc = 1;
        fprintf(stderr, "Warning: num_vc not specified, setting to %d\n",
                p->num_vc);
    }

    int rc = configuration_get_value(&config, "PARAMS", "dim_length", anno,
            dim_length_str, MAX_NAME_LENGTH);
    if (rc == 0){
        tw_error(TW_LOC, "couldn't read PARAMS:dim_length");
    }
    char* token;
    p->dim_length=malloc(p->n_dims*sizeof(*p->dim_length));
    token = strtok(dim_length_str, ",");
    i = 0;
    while(token != NULL)
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    {
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        sscanf(token, "%d", &p->dim_length[i]);
        if(p->dim_length[i] <= 0)
        {
            tw_error(TW_LOC, "Invalid torus dimension specified "
                    "(%d at pos %d), exiting... ", p->dim_length[i], i);
        }
        i++;
        token = strtok(NULL,",");
    }
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    /*int num_nodes = 1;

    for( i = 0; i < p->n_dims; i++)
	   num_nodes *= p->dim_length[i];
    
    configuration_get_value_int(&config, "PARAMS", "num_net_traces", anno, &p->num_net_traces);
    if(!p->num_net_traces) {
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	p->num_net_traces = num_nodes;
        fprintf(stderr, "Number of network traces not specified, setting to %d",
                p->num_net_traces);
    }
   // Number of network traces should be <= number of torus network nodes `
   assert(p->num_net_traces <= num_nodes);*/
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    // create derived parameters
   
    // factor is an exclusive prefix product
    p->factor = malloc(p->n_dims * sizeof(int));
    p->factor[0] = 1;
    for(i = 1; i < p->n_dims; i++)
        p->factor[i] = p->factor[i-1] * p->dim_length[i-1];

    p->half_length = malloc(p->n_dims * sizeof(int));
    for (i = 0; i < p->n_dims; i++)
        p->half_length[i] = p->dim_length[i] / 2;

    // some latency numbers
    p->head_delay = (1.0 / p->link_bandwidth) * p->chunk_size;
    p->credit_delay = (1.0 / p->link_bandwidth) * p->chunk_size;
}

static void torus_configure(){
    anno_map = codes_mapping_get_lp_anno_map(LP_CONFIG_NM);
    assert(anno_map);
    num_params = anno_map->num_annos + (anno_map->has_unanno_lp > 0);
    all_params = malloc(num_params * sizeof(*all_params));

    for (uint64_t i = 0; i < anno_map->num_annos; i++){
        const char * anno = anno_map->annotations[i];
        torus_read_config(anno, &all_params[i]);
    }
    if (anno_map->has_unanno_lp > 0){
        torus_read_config(NULL, &all_params[anno_map->num_annos]);
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    }
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}

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void torus_collective_init(nodes_state * s,
           		   tw_lp * lp)
{
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    // TODO: be annotation-aware somehow 
    codes_mapping_get_lp_info(lp->gid, grp_name, &mapping_grp_id, NULL, &mapping_type_id, NULL, &mapping_rep_id, &mapping_offset);
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    int num_lps = codes_mapping_get_lp_count(grp_name, 1, LP_CONFIG_NM, s->anno, 0);
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    int num_reps = codes_mapping_get_group_reps(grp_name);
    s->node_id = (mapping_rep_id * num_lps) + mapping_offset;

    int i;
   /* handle collective operations by forming a tree of all the LPs */
   /* special condition for root of the tree */
   if( s->node_id == 0)
    {
        s->parent_node_id = -1;
        s->is_root = 1;
   }
   else
   {
       s->parent_node_id = (s->node_id - ((s->node_id - 1) % TREE_DEGREE)) / TREE_DEGREE;
       s->is_root = 0;
   }
   s->children = (tw_lpid*)malloc(TREE_DEGREE * sizeof(tw_lpid));

   /* set the isleaf to zero by default */
   s->is_leaf = 1;
   s->num_children = 0;

   /* calculate the children of the current node. If its a leaf, no need to set children,
      only set isleaf and break the loop*/

   for( i = 0; i < TREE_DEGREE; i++ )
    {
        tw_lpid next_child = (TREE_DEGREE * s->node_id) + i + 1;
        if(next_child < (num_lps * num_reps))
        {
            s->num_children++;
            s->is_leaf = 0;
            s->children[i] = next_child;
        }
        else
           s->children[i] = -1;
    }

#if TORUS_COLLECTIVE_DEBUG == 1
   printf("\n LP %ld parent node id ", s->node_id);

   for( i = 0; i < TREE_DEGREE; i++ )
        printf(" child node ID %ld ", s->children[i]);
   printf("\n");

   if(s->is_leaf)
        printf("\n LP %ld is leaf ", s->node_id);
#endif
}
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/* torus packet reverse event */
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static void torus_packet_event_rc(tw_lp *sender)
{
  codes_local_latency_reverse(sender);
  return;
}

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/* returns the torus message size */
static int torus_get_msg_sz(void)
{
   return sizeof(nodes_message);
}

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/* torus packet event , generates a torus packet on the compute node */
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static tw_stime torus_packet_event(char* category, tw_lpid final_dest_lp, uint64_t packet_size, int is_pull, uint64_t pull_size, tw_stime offset, const mn_sched_params *sched_params, int remote_event_size, const void* remote_event, int self_event_size, const void* self_event, tw_lpid src_lp, tw_lp *sender, int is_last_pckt)
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{
    tw_event * e_new;
    tw_stime xfer_to_nic_time;
    nodes_message * msg;
    char* tmp_ptr;
   
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    xfer_to_nic_time = g_tw_lookahead + codes_local_latency(sender); /* Throws an error of found last KP time > current event time otherwise */
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    //e_new = tw_event_new(local_nic_id, xfer_to_nic_time+offset, sender);
    //msg = tw_event_data(e_new);
    e_new = model_net_method_event_new(sender->gid, xfer_to_nic_time+offset,
            sender, TORUS, (void**)&msg, (void**)&tmp_ptr);
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    strcpy(msg->category, category);
    msg->final_dest_gid = final_dest_lp;
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    msg->sender_svr= src_lp;
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    msg->packet_size = packet_size;
    msg->remote_event_size_bytes = 0;
    msg->local_event_size_bytes = 0;
    msg->type = GENERATE;
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    msg->is_pull = is_pull;
    msg->pull_size = pull_size;
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    if(is_last_pckt) /* Its the last packet so pass in remote event information*/
     {
	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;
	}
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      // 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);
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     }
    tw_event_send(e_new);
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    return xfer_to_nic_time;
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}
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/*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;
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    char anno[MAX_NAME_LENGTH];
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    codes_mapping_get_lp_info(lp->gid, grp_name, &mapping_grp_id, NULL, &mapping_type_id, anno, &mapping_rep_id, &mapping_offset);
    if (anno[0] == '\0'){
        s->anno = NULL;
        s->params = &all_params[num_params-1];
    }
    else{
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        s->anno = strdup(anno);
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        int id = configuration_get_annotation_index(anno, anno_map);
        s->params = &all_params[id];
    }
    int dim_N[ s->params->n_dims + 1 ];
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    // shorthand
    const torus_param *p = s->params;
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    dim_N[ 0 ]=mapping_rep_id + mapping_offset;
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    s->neighbour_minus_lpID = (int*)malloc(p->n_dims * sizeof(int));
    s->neighbour_plus_lpID = (int*)malloc(p->n_dims * sizeof(int));
    s->dim_position = (int*)malloc(p->n_dims * sizeof(int));
    s->buffer = (int**)malloc(2*p->n_dims * sizeof(int*));
    s->next_link_available_time = 
        (tw_stime**)malloc(2*p->n_dims * sizeof(tw_stime*));
    s->next_credit_available_time = 
        (tw_stime**)malloc(2*p->n_dims * sizeof(tw_stime*));
    s->next_flit_generate_time = 
        (tw_stime**)malloc(2*p->n_dims*sizeof(tw_stime*));

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

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

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  int temp_dim_pos[ p->n_dims ];
  for ( i = 0; i < p->n_dims; i++ )
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    temp_dim_pos[ i ] = s->dim_position[ i ];

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

  //printf("\n");
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  for( j=0; j < 2 * p->n_dims; j++ )
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   {
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    for( i = 0; i < p->num_vc; i++ )
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     {
       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;
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    torus_collective_init(s, lp);
}


/* collective operation for the torus network */
void torus_collective(char* category, int message_size, int remote_event_size, const void* remote_event, tw_lp* sender)
{
    tw_event * e_new;
    tw_stime xfer_to_nic_time;
    nodes_message * msg;
    tw_lpid local_nic_id;
    char* tmp_ptr;

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    // TODO: be annotation-aware
    codes_mapping_get_lp_info(sender->gid, grp_name, &mapping_grp_id, NULL,
            &mapping_type_id, NULL, &mapping_rep_id, &mapping_offset);
    codes_mapping_get_lp_id(grp_name, LP_CONFIG_NM, NULL, 1,
            mapping_rep_id, mapping_offset, &local_nic_id);
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    xfer_to_nic_time = g_tw_lookahead + codes_local_latency(sender);
    e_new = model_net_method_event_new(local_nic_id, xfer_to_nic_time,
            sender, TORUS, (void**)&msg, (void**)&tmp_ptr);

    msg->remote_event_size_bytes = message_size;
    strcpy(msg->category, category);
    msg->sender_svr=sender->gid;
    msg->type = T_COLLECTIVE_INIT;

    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;
     }

    tw_event_send(e_new);
    return;
}

/* reverse for collective operation of the dragonfly network */
void torus_collective_rc(int message_size, tw_lp* sender)
{
     codes_local_latency_reverse(sender);
     return;
}

static void send_remote_event(nodes_state * s,
                        tw_bf * bf,
                        nodes_message * msg,
                        tw_lp * lp)
{
    // Trigger an event on receiving server
    if(msg->remote_event_size_bytes)
     {
            tw_event* e;
            tw_stime ts;
            nodes_message * m;
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            ts = (1/s->params->link_bandwidth) * msg->remote_event_size_bytes;
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            e = codes_event_new(s->origin_svr, 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);
     }
}

static void node_collective_init(nodes_state * s,
                        tw_bf * bf,
                        nodes_message * msg,
                        tw_lp * lp)
{
        tw_event * e_new;
        tw_lpid parent_nic_id;
        tw_stime xfer_to_nic_time;
        nodes_message * msg_new;
        int num_lps;

        msg->saved_collective_init_time = s->collective_init_time;
        s->collective_init_time = tw_now(lp);
	s->origin_svr = msg->sender_svr;
	
        if(s->is_leaf)
        {
            //printf("\n LP %ld sending message to parent %ld ", s->node_id, s->parent_node_id);
            /* get the global LP ID of the parent node */
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            // TODO: be annotation-aware
            codes_mapping_get_lp_info(lp->gid, grp_name, &mapping_grp_id, NULL,
                    &mapping_type_id, NULL, &mapping_rep_id, &mapping_offset);
            num_lps = codes_mapping_get_lp_count(grp_name, 1, LP_CONFIG_NM,
                    NULL, 1);
            codes_mapping_get_lp_id(grp_name, LP_CONFIG_NM, NULL, 1,
                    s->parent_node_id/num_lps, (s->parent_node_id % num_lps),
                    &parent_nic_id);
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           /* send a message to the parent that the LP has entered the collective operation */
            xfer_to_nic_time = g_tw_lookahead + LEVEL_DELAY;
            //e_new = codes_event_new(parent_nic_id, xfer_to_nic_time, lp);
	    void* m_data;
	    e_new = model_net_method_event_new(parent_nic_id, xfer_to_nic_time,
            	lp, TORUS, (void**)&msg_new, (void**)&m_data);
	    	
            memcpy(msg_new, msg, sizeof(nodes_message));
	    if (msg->remote_event_size_bytes){
        	memcpy(m_data, model_net_method_get_edata(TORUS, msg),
                	msg->remote_event_size_bytes);
      	    }
	    
            msg_new->type = T_COLLECTIVE_FAN_IN;
            msg_new->sender_node = s->node_id;

            tw_event_send(e_new);
        }
        return;
}

static void node_collective_fan_in(nodes_state * s,
                        tw_bf * bf,
                        nodes_message * msg,
                        tw_lp * lp)
{
        int i;
        s->num_fan_nodes++;

598 599 600 601 602
        // TODO: be annotation-aware
        codes_mapping_get_lp_info(lp->gid, grp_name, &mapping_grp_id, NULL,
                &mapping_type_id, NULL, &mapping_rep_id, &mapping_offset);
        int num_lps = codes_mapping_get_lp_count(grp_name, 1, LP_CONFIG_NM,
                NULL, 1);
603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620

        tw_event* e_new;
        nodes_message * msg_new;
        tw_stime xfer_to_nic_time;

        bf->c1 = 0;
        bf->c2 = 0;

        /* if the number of fanned in nodes have completed at the current node then signal the parent */
        if((s->num_fan_nodes == s->num_children) && !s->is_root)
        {
            bf->c1 = 1;
            msg->saved_fan_nodes = s->num_fan_nodes-1;
            s->num_fan_nodes = 0;
            tw_lpid parent_nic_id;
            xfer_to_nic_time = g_tw_lookahead + LEVEL_DELAY;

            /* get the global LP ID of the parent node */
621 622 623
            codes_mapping_get_lp_id(grp_name, LP_CONFIG_NM, NULL, 1,
                    s->parent_node_id/num_lps, (s->parent_node_id % num_lps),
                    &parent_nic_id);
624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659

           /* send a message to the parent that the LP has entered the collective operation */
            //e_new = codes_event_new(parent_nic_id, xfer_to_nic_time, lp);
            //msg_new = tw_event_data(e_new);
	    void * m_data;
      	    e_new = model_net_method_event_new(parent_nic_id,
              xfer_to_nic_time,
              lp, TORUS, (void**)&msg_new, &m_data);
	    
            memcpy(msg_new, msg, sizeof(nodes_message));
            msg_new->type = T_COLLECTIVE_FAN_IN;
            msg_new->sender_node = s->node_id;

            if (msg->remote_event_size_bytes){
	        memcpy(m_data, model_net_method_get_edata(TORUS, msg),
        	        msg->remote_event_size_bytes);
      	   }
	    
            tw_event_send(e_new);
      }

      /* root node starts off with the fan-out phase */
      if(s->is_root && (s->num_fan_nodes == s->num_children))
      {
           bf->c2 = 1;
           msg->saved_fan_nodes = s->num_fan_nodes-1;
           s->num_fan_nodes = 0;
           send_remote_event(s, bf, msg, lp);

           for( i = 0; i < s->num_children; i++ )
           {
                tw_lpid child_nic_id;
                /* Do some computation and fan out immediate child nodes from the collective */
                xfer_to_nic_time = g_tw_lookahead + COLLECTIVE_COMPUTATION_DELAY + LEVEL_DELAY + tw_rand_exponential(lp->rng, (double)LEVEL_DELAY/50);

                /* get global LP ID of the child node */
660 661 662
                codes_mapping_get_lp_id(grp_name, LP_CONFIG_NM, NULL, 1,
                        s->children[i]/num_lps, (s->children[i] % num_lps),
                        &child_nic_id);
663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682
                //e_new = codes_event_new(child_nic_id, xfer_to_nic_time, lp);

                //msg_new = tw_event_data(e_new);
                void * m_data;
	        e_new = model_net_method_event_new(child_nic_id,
                xfer_to_nic_time,
		lp, TORUS, (void**)&msg_new, &m_data);

		memcpy(msg_new, msg, sizeof(nodes_message));
	        if (msg->remote_event_size_bytes){
	                memcpy(m_data, model_net_method_get_edata(TORUS, msg),
        	               msg->remote_event_size_bytes);
      		}
		
                msg_new->type = T_COLLECTIVE_FAN_OUT;
                msg_new->sender_node = s->node_id;

                tw_event_send(e_new);
           }
      }
683
}
684 685 686 687 688 689 690
	     
static void node_collective_fan_out(nodes_state * s,
                        tw_bf * bf,
                        nodes_message * msg,
                        tw_lp * lp)
{
        int i;
691 692 693
        //TODO: be annotation-aware
        int num_lps = codes_mapping_get_lp_count(grp_name, 1, LP_CONFIG_NM,
                NULL, 1);
694 695 696 697
        bf->c1 = 0;
        bf->c2 = 0;

        send_remote_event(s, bf, msg, lp);
698

699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714
        if(!s->is_leaf)
        {
            bf->c1 = 1;
            tw_event* e_new;
            nodes_message * msg_new;
            tw_stime xfer_to_nic_time;

           for( i = 0; i < s->num_children; i++ )
           {
                xfer_to_nic_time = g_tw_lookahead + TORUS_FAN_OUT_DELAY + tw_rand_exponential(lp->rng, (double)TORUS_FAN_OUT_DELAY/10);

                if(s->children[i] > 0)
                {
                        tw_lpid child_nic_id;

                        /* get global LP ID of the child node */
715 716 717
                        codes_mapping_get_lp_id(grp_name, LP_CONFIG_NM, NULL, 1,
                                s->children[i]/num_lps,
                                (s->children[i] % num_lps), &child_nic_id);
718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745
                        //e_new = codes_event_new(child_nic_id, xfer_to_nic_time, lp);
                        //msg_new = tw_event_data(e_new);
                        //memcpy(msg_new, msg, sizeof(nodes_message) + msg->remote_event_size_bytes);
			void* m_data;
			e_new = model_net_method_event_new(child_nic_id,
							xfer_to_nic_time,
					                lp, TORUS, (void**)&msg_new, &m_data);
		        memcpy(msg_new, msg, sizeof(nodes_message));
		        if (msg->remote_event_size_bytes){
			        memcpy(m_data, model_net_method_get_edata(TORUS, msg),
			                msg->remote_event_size_bytes);
      			}


                        msg_new->type = T_COLLECTIVE_FAN_OUT;
                        msg_new->sender_node = s->node_id;
                        tw_event_send(e_new);
                }
           }
         }
	//printf("\n Fan out phase completed %ld ", lp->gid);
        if(max_collective < tw_now(lp) - s->collective_init_time )
          {
              bf->c2 = 1;
              max_collective = tw_now(lp) - s->collective_init_time;
          }
}
    
746 747 748 749 750 751
/*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 )
{
752 753
  int dim_N[s->params->n_dims], 
      dest[s->params->n_dims],
754 755 756
      i,
      dest_id=0;

757 758
  //TODO: be annotation-aware
  codes_mapping_get_lp_info(*dst_lp, grp_name, &mapping_grp_id, NULL, &mapping_type_id, NULL, &mapping_rep_id, &mapping_offset);
759
  dim_N[ 0 ]=mapping_rep_id + mapping_offset;
760 761

  // find destination dimensions using destination LP ID 
762
  for ( i = 0; i < s->params->n_dims; i++ )
763
    {
764 765
      dest[ i ] = dim_N[ i ] % s->params->dim_length[ i ];
      dim_N[ i + 1 ] = ( dim_N[ i ] - dest[ i ] ) / s->params->dim_length[ i ];
766 767
    }

768
  for( i = 0; i < s->params->n_dims; i++ )
769
    {
770
      if ( s->dim_position[ i ] - dest[ i ] > s->params->half_length[ i ] )
771 772 773 774 775 776
	{
	  dest_id = s->neighbour_plus_lpID[ i ];
	  *dim = i;
	  *dir = 1;
	  break;
	}
777
      if ( s->dim_position[ i ] - dest[ i ] < -s->params->half_length[ i ] )
778 779 780 781 782 783
	{
	  dest_id = s->neighbour_minus_lpID[ i ];
	  *dim = i;
	  *dir = 0;
	  break;
	}
784 785
      if ( ( s->dim_position[i] - dest[i] <= s->params->half_length[i] ) &&
              ( s->dim_position[ i ] - dest[ i ] > 0 ) )
786 787 788 789 790 791
	{
	  dest_id = s->neighbour_minus_lpID[ i ];
	  *dim = i;
	  *dir = 0;
	  break;
	}
792 793
      if (( s->dim_position[i] - dest[i] >= -s->params->half_length[i] ) &&
              ( s->dim_position[ i ] - dest[ i ] < 0) )
794 795 796 797 798 799 800
	{
	  dest_id = s->neighbour_plus_lpID[ i ];
	  *dim = i;
	  *dir = 1;
	  break;
	}
    }
801
  codes_mapping_get_lp_id(grp_name, LP_CONFIG_NM, NULL, 1, dest_id, 0, dst_lp);
802
}
803 804 805 806 807 808

/*Generates a packet. If there is a buffer slot available, then the packet is 
injected in the network. Else, a buffer overflow exception is thrown.
TODO: We might want to modify this so that if the buffer is full, the packet
injection is delayed in turn slowing down the injection rate. The average achieved
injection rate can be reported at the end of the simulation. */
809 810 811 812 813 814
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);
815
    int j, tmp_dir=-1, tmp_dim=-1, total_event_size;
816 817 818 819 820 821
    tw_stime ts;

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

822 823 824
    int mapping_grp_id, mapping_rep_id, mapping_type_id, mapping_offset;
    tw_lpid dst_lp;
    // TODO: be annotation-aware
825 826 827
    dst_lp = model_net_find_local_device(TORUS, s->anno, 0,
            msg->final_dest_gid);
            //mapping_offset, &dst_lp);
828 829 830 831
    // dest_lp gets included to other required msgs through memcpys, so just
    // set here
    msg->dest_lp = dst_lp;

832 833 834 835 836 837 838 839
    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;
840
    msg->my_N_hop = 0;
841

842 843 844 845
    uint64_t num_chunks = msg->packet_size/s->params->chunk_size;
    if(msg->packet_size % s->params->chunk_size)
        num_chunks++;

846

847 848 849 850 851 852
    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++)
    { 
853
     if(s->buffer[ tmp_dir + ( tmp_dim * 2 ) ][ 0 ] < s->params->buffer_size)
854 855 856 857 858
      {
       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);
859
       //e_h = tw_event_new(lp->gid, ts, lp);
860 861 862
       msg->source_direction = tmp_dir;
       msg->source_dim = tmp_dim;

863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879
       void *m_data;
       e_h = model_net_method_event_new(lp->gid, ts, lp, TORUS, (void**)&m,
               (void**)&m_data);

       //m = tw_event_data( e_h );
       //memcpy(m, msg, torus_get_msg_sz() + msg->local_event_size_bytes + msg->remote_event_size_bytes);
       void *m_data_src = model_net_method_get_edata(TORUS, msg);
       memcpy(m, msg, sizeof(nodes_message));
       if (msg->remote_event_size_bytes){
           memcpy(m_data, m_data_src,
                   msg->remote_event_size_bytes);
           m_data = (char*)m_data + msg->remote_event_size_bytes;
           m_data_src = (char*)m_data_src + msg->remote_event_size_bytes;
       }
       if (msg->local_event_size_bytes){
           memcpy(m_data, m_data_src, msg->local_event_size_bytes);
       }
880 881 882 883 884 885 886 887 888 889 890 891
       m->next_stop = dst_lp;
       m->chunk_id = j;

      // find destination dimensions using destination LP ID 
       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);
892 893
       MPI_Finalize();
       exit(-1); 
894 895
       }
   }
896

897
   total_event_size = model_net_get_msg_sz(TORUS) + msg->remote_event_size_bytes + msg->local_event_size_bytes;   
898 899 900 901 902
   /* record the statistics of the generated packets */
   mn_stats* stat;
   stat = model_net_find_stats(msg->category, s->torus_stats_array);
   stat->send_count++;  
   stat->send_bytes += msg->packet_size;
903
   stat->send_time += (1/s->params->link_bandwidth) * msg->packet_size;
904 905 906
   /* record the maximum ROSS event size */
   if(stat->max_event_size < total_event_size)
	   stat->max_event_size = total_event_size;
907 908 909 910 911 912 913 914
}
/*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
915
    //printf("\n (%lf) sending credit tmp_dir %d tmp_dim %d %lf ", tw_now(lp), msg->source_direction, msg->source_dim, s->params->credit_delay );
916 917 918 919 920 921 922 923 924
#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];
925
    s->next_credit_available_time[(2 * src_dim) + src_dir][0] = maxd(s->next_credit_available_time[(2 * src_dim) + src_dir][0], tw_now(lp));
926 927
    ts =  s->params->credit_delay + 
        tw_rand_exponential(lp->rng, s->params->credit_delay/1000);
928 929
    s->next_credit_available_time[(2 * src_dim) + src_dir][0] += ts;

930 931
    //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);
932
    buf_e = model_net_method_event_new(msg->sender_node,
933 934
            s->next_credit_available_time[(2*src_dim) + src_dir][0] - tw_now(lp),
            lp, TORUS, (void**)&m, NULL);
935 936 937 938 939 940
    m->source_direction = msg->source_direction;
    m->source_dim = msg->source_dim;

    m->type = CREDIT;
    tw_event_send( buf_e );
}
941 942
/* 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 */
943 944 945 946 947 948 949 950 951 952 953 954 955 956
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 );     

957
    if(s->buffer[ tmp_dir + ( tmp_dim * 2 ) ][ 0 ] < s->params->buffer_size)
958 959 960 961
    {
       bf->c2 = 1;
       msg->saved_src_dir = tmp_dir;
       msg->saved_src_dim = tmp_dim;
962 963
       ts = tw_rand_exponential( lp->rng, s->params->head_delay/200.0 ) + 
           s->params->head_delay;
964 965 966 967

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

968
      s->next_link_available_time[tmp_dir + ( tmp_dim * 2 )][0] = maxd( s->next_link_available_time[ tmp_dir + ( tmp_dim * 2 )][0], tw_now(lp) );
969 970
      s->next_link_available_time[tmp_dir + ( tmp_dim * 2 )][0] += ts;
    
971 972 973 974 975 976 977 978 979 980 981 982
      //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);
      void * m_data;
      e = model_net_method_event_new(dst_lp, 
              s->next_link_available_time[tmp_dir+(tmp_dim*2)][0] - tw_now(lp),
              lp, TORUS, (void**)&m, &m_data);
      memcpy(m, msg, sizeof(nodes_message));
      if (msg->remote_event_size_bytes){
        memcpy(m_data, model_net_method_get_edata(TORUS, msg),
                msg->remote_event_size_bytes);
      }
983 984 985 986 987 988 989 990
      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;
991
      m->sender_node = lp->gid;
992 993 994 995 996 997
      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 ]++;
    
998 999 1000 1001 1002
      uint64_t num_chunks = msg->packet_size/s->params->chunk_size;

      if(msg->packet_size % s->params->chunk_size)
          num_chunks++;

1003 1004 1005
      if(msg->chunk_id == num_chunks - 1)
      {
        bf->c1 = 1;
1006
	/* Invoke an event on the sending server */
1007 1008 1009 1010
	if(msg->local_event_size_bytes > 0)
	{
          tw_event* e_new;
	  nodes_message* m_new;
1011
	  void* local_event;
1012
	  ts = (1/s->params->link_bandwidth) * msg->local_event_size_bytes;
1013
	  e_new = tw_event_new(msg->sender_svr, ts, lp);
1014
	  m_new = tw_event_data(e_new);
1015 1016 1017 1018
	  //local_event = (char*)msg;
	  //local_event += torus_get_msg_sz() + msg->remote_event_size_bytes;
          local_event = (char*)model_net_method_get_edata(TORUS, msg) +
              msg->remote_event_size_bytes;
1019 1020 1021 1022 1023 1024
	  memcpy(m_new, local_event, msg->local_event_size_bytes);
	  tw_event_send(e_new);
	}
     }
  } // end if
    else
1025
    {
1026
	    printf("\n buffer overflown ");
1027 1028 1029
	    MPI_Finalize();
	    exit(-1);
    }
1030 1031
}

1032 1033 1034
/*Processes the packet after it arrives from the neighboring torus node 
 * routes it to the next compute node if this is not the destination
 * OR if this is the destination then a remote event at the server is issued. */
1035 1036 1037 1038 1039 1040 1041 1042 1043
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;
1044
  mn_stats* stat;
1045

1046
  credit_send( s, bf, lp, msg); 
1047 1048 1049 1050 1051 1052 1053
  
  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 )
    {   
1054 1055 1056 1057
        uint64_t num_chunks = msg->packet_size/s->params->chunk_size;
        if(msg->packet_size % s->params->chunk_size)
            num_chunks++;

1058 1059 1060
        if( msg->chunk_id == num_chunks - 1 )    
        {
	    bf->c2 = 1;
1061 1062 1063 1064 1065 1066
	    stat = model_net_find_stats(msg->category, s->torus_stats_array);
	    stat->recv_count++;
	    stat->recv_bytes += msg->packet_size;
	    stat->recv_time += tw_now( lp ) - msg->travel_start_time;

	    /*count the number of packets completed overall*/
1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078
	    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)
	    {
1079
               void *tmp_ptr = model_net_method_get_edata(TORUS, msg);
1080
               if (msg->is_pull){
1081
                   int net_id = model_net_get_id(LP_METHOD_NM);
1082
                   model_net_event(net_id, msg->category, msg->sender_svr,
1083
                           msg->pull_size, 0.0, msg->remote_event_size_bytes,
1084 1085 1086 1087 1088 1089 1090 1091
                           tmp_ptr, 0, NULL, lp);
               }
               else{
                   e = tw_event_new(msg->final_dest_gid, ts, lp);
                   m = tw_event_data(e);
                   memcpy(m, tmp_ptr, msg->remote_event_size_bytes);
                   tw_event_send(e);
               }
1092 1093 1094 1095 1096
	    }
       }
    }
  else
    {
1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107
      //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);
      void *m_data;
      e = model_net_method_event_new(lp->gid, ts, lp, TORUS, (void**)&m,
              &m_data);
      memcpy(m, msg, sizeof(nodes_message));
      if (msg->remote_event_size_bytes){
        memcpy(m_data, model_net_method_get_edata(TORUS, msg),
                msg->remote_event_size_bytes);
      }
1108 1109 1110 1111 1112 1113
      m->type = SEND;
      m->next_stop = -1;
      tw_event_send(e);
   }
}

1114 1115
/* reports torus statistics like average packet latency, maximum packet latency and average
 * number of torus hops traversed by the packet */
1116 1117
static void torus_report_stats()
{
1118
    long long avg_hops, total_finished_packets;
1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130
    tw_stime avg_time, max_time;

    MPI_Reduce( &total_hops, &avg_hops, 1, MPI_LONG_LONG, MPI_SUM, 0, MPI_COMM_WORLD);
    MPI_Reduce( &N_finished_packets, &total_finished_packets, 1, MPI_LONG_LONG, MPI_SUM, 0, MPI_COMM_WORLD);
    MPI_Reduce( &total_time, &avg_time, 1,MPI_DOUBLE, MPI_SUM, 0, MPI_COMM_WORLD);
    MPI_Reduce( &max_latency, &max_time, 1, MPI_DOUBLE, MPI_MAX, 0, MPI_COMM_WORLD);

    if(!g_tw_mynode)
     {
       printf(" Average number of hops traversed %f average message latency %lf us maximum message latency %lf us \n", (float)avg_hops/total_finished_packets, avg_time/(total_finished_packets*1000), max_time/1000);
     }
}
1131
/* finalize the torus node and free all event buffers available */
1132 1133 1134
void
final( nodes_state * s, tw_lp * lp )
{
1135
  model_net_print_stats(lp->gid, &s->torus_stats_array[0]); 
1136 1137 1138
  free(s->next_link_available_time);
  free(s->next_credit_available_time);
  free(s->next_flit_generate_time);
1139 1140 1141 1142 1143 1144
  // since all LPs are sharing params, just let them leak for now
  // TODO: add a post-sim "cleanup" function?
  //free(s->buffer); 
  //free(s->params->dim_length);
  //free(s->params->factor);
  //free(s->params->half_length);
1145 1146
}

1147
/* increments the buffer count after a credit arrives from the remote compute node */
1148 1149 1150 1151
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 ]--;
}
1152

1153
/* reverse handler for torus node */
1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164
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;

1165 1166 1167 1168
                     uint64_t num_chunks = msg->packet_size/s->params->chunk_size;
                     if(msg->packet_size % s->params->chunk_size)
                         num_chunks++;

1169 1170
		     //s->next_flit_generate_time[(saved_dim * 2) + saved_dir][0] = msg->saved_available_time;
		     for(i=0; i < num_chunks; i++)
1171 1172 1173 1174 1175
  		        tw_rand_reverse_unif(lp->rng);
	     	     mn_stats* stat;
		     stat = model_net_find_stats(msg->category, s->torus_stats_array);
		     stat->send_count--; 
		     stat->send_bytes -= msg->packet_size;
1176
		     stat->send_time -= (1/s->params->link_bandwidth) * msg->packet_size;
1177 1178 1179 1180 1181 1182 1183 1184 1185
		   }
	break;
	
	case ARRIVAL:
		   {
  		    tw_rand_reverse_unif(lp->rng);
		    tw_rand_reverse_unif(lp->rng);
		    int next_dim = msg->source_dim;
		    int next_dir = msg->source_direction;
1186 1187 1188
                    uint64_t num_chunks = msg->packet_size/s->params->chunk_size;
                    if(msg->packet_size % s->params->chunk_size)
                        num_chunks++;
1189 1190 1191 1192

		    s->next_credit_available_time[next_dir + ( next_dim * 2 )][0] = msg->saved_available_time;
		    if(bf->c2)
		    {
1193 1194 1195 1196 1197
		       struct mn_stats* stat;
		       stat = model_net_find_stats(msg->category, s->torus_stats_array);
		       stat->recv_count--;
		       stat->recv_bytes -= msg->packet_size;
		        stat->recv_time -= tw_now