wimaxscheduler.cc

Ns2下Wimax的代码

/* This software was developed at the National Institute of Standards and
 * Technology by employees of the Federal Government in the course of
 * their official duties. Pursuant to title 17 Section 105 of the United
 * States Code this software is not subject to copyright protection and
 * is in the public domain.
 * NIST assumes no responsibility whatsoever for its use by other parties,
 * and makes no guarantees, expressed or implied, about its quality,
 * reliability, or any other characteristic.
 * <BR>
 * We would appreciate acknowledgement if the software is used.
 * <BR>
 * NIST ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" CONDITION AND
 * DISCLAIM ANY LIABILITY OF ANY KIND FOR ANY DAMAGES WHATSOEVER RESULTING
 * FROM THE USE OF THIS SOFTWARE.
 * </PRE></P>
 * @author  rouil
 */

#include "wimaxscheduler.h"

/*
 * Create a scheduler
 * @param mac The Mac where it is located
 */
WimaxScheduler::WimaxScheduler ()
{
}

/*
 * Set the mac
 * @param mac The Mac where it is located
 */
void WimaxScheduler::setMac (Mac802_16 *mac)
{
  assert (mac!=NULL);

  mac_ = mac;
}

/**
 * Initialize the scheduler.
 */
void WimaxScheduler::init()
{

}

/**
 * This function is used to schedule bursts/packets
 */
void WimaxScheduler::schedule ()
{
  //defined by subclasses
}


/**
 * Transfer the packets from the given connection to the given burst
 * @param con The connection
 * @param b The burst
 * @param b_data Amount of data in the burst
 * @return the new burst occupation
 */
int WimaxScheduler::transfer_packets (Connection *c, Burst *b, int b_data)
{
  Packet *p;
  hdr_cmn* ch;
  hdr_mac802_16 *wimaxHdr;
  double txtime, txtime2;
  int txtime_s;
  bool pkt_transfered = false;
  OFDMPhy *phy = mac_->getPhy();

  p = c->get_queue()->head();

  int max_data;
  if (mac_->getNodeType()==STA_BS)
    max_data = phy->getMaxPktSize (b->getDuration(), mac_->getMap()->getDlSubframe()->getProfile (b->getIUC())->getEncoding())-b_data;
  else
    max_data = phy->getMaxPktSize (b->getDuration(), mac_->getMap()->getUlSubframe()->getProfile (b->getIUC())->getEncoding())-b_data;

  debug2 ("In Mac %d max data=%d (burst duration=%d, b_data=%d)\n", mac_->addr(), max_data, b->getDuration(), b_data);
  if (max_data < HDR_MAC802_16_SIZE ||
      (c->getFragmentationStatus()!=FRAG_NOFRAG && max_data < HDR_MAC802_16_SIZE+HDR_MAC802_16_FRAGSUB_SIZE))
    return b_data; //not even space for header

  while (p) {
    ch = HDR_CMN(p);
    wimaxHdr = HDR_MAC802_16(p);

    if (mac_->getNodeType()==STA_BS)
      max_data = phy->getMaxPktSize (b->getDuration(), mac_->getMap()->getDlSubframe()->getProfile (b->getIUC())->getEncoding())-b_data;
    else
      max_data = phy->getMaxPktSize (b->getDuration(), mac_->getMap()->getUlSubframe()->getProfile (b->getIUC())->getEncoding())-b_data;

    debug2 ("\tIn Mac %d max data=%d (burst duration=%d, b_data=%d)\n", mac_->addr(), max_data, b->getDuration(), b_data);
    if (max_data < HDR_MAC802_16_SIZE ||
        (c->getFragmentationStatus()!=FRAG_NOFRAG && max_data < HDR_MAC802_16_SIZE+HDR_MAC802_16_FRAGSUB_SIZE))
      return b_data; //not even space for header

    if (c->getFragmentationStatus()!=FRAG_NOFRAG) {
      if (max_data >= ch->size()-c->getFragmentBytes()+HDR_MAC802_16_FRAGSUB_SIZE) {
        //add fragmentation header
        wimaxHdr->header.type_frag = true;
        //no need to fragment again
        wimaxHdr->frag_subheader.fc = FRAG_LAST;
        wimaxHdr->frag_subheader.fsn = c->getFragmentNumber ();
        //remove packet from queue
        c->dequeue();
	ch->size() = ch->size()-c->getFragmentBytes()+HDR_MAC802_16_FRAGSUB_SIZE; //new packet size
        //update fragmentation
        debug2 ("End of fragmentation %d (max_data=%d, bytes to send=%d\n", wimaxHdr->frag_subheader.fsn, max_data, ch->size());
        c->updateFragmentation (FRAG_NOFRAG, 0, 0);
      } else {
	//need to fragment the packet again
        p = p->copy(); //copy packet to send
        ch = HDR_CMN(p);
        wimaxHdr = HDR_MAC802_16(p);
        //add fragmentation header
        wimaxHdr->header.type_frag = true;
        wimaxHdr->frag_subheader.fc = FRAG_CONT;
        wimaxHdr->frag_subheader.fsn = c->getFragmentNumber ();
        ch->size() = max_data; //new packet size
        //update fragmentation
        c->updateFragmentation (FRAG_CONT, (c->getFragmentNumber ()+1)%8, c->getFragmentBytes()+max_data-(HDR_MAC802_16_SIZE+HDR_MAC802_16_FRAGSUB_SIZE));
        debug2 ("Continue fragmentation %d\n", wimaxHdr->frag_subheader.fsn);
      }
    } else {
      if (max_data < ch->size() && c->isFragEnable()) {
        //need to fragment the packet for the first time
        p = p->copy(); //copy packet to send
        ch = HDR_CMN(p);
        wimaxHdr = HDR_MAC802_16(p);
        //add fragmentation header
        wimaxHdr->header.type_frag = true;
        wimaxHdr->frag_subheader.fc = FRAG_FIRST;
        wimaxHdr->frag_subheader.fsn = c->getFragmentNumber ();
        ch->size() = max_data; //new packet size
        //update fragmentation
        c->updateFragmentation (FRAG_FIRST, 1, c->getFragmentBytes()+max_data-(HDR_MAC802_16_SIZE+HDR_MAC802_16_FRAGSUB_SIZE));
        debug2 ("First fragmentation\n");
      } else if (max_data < ch->size() && !c->isFragEnable()) {
        //the connection does not support fragmentation
        //can't move packets anymore
        return b_data;
      } else {
        //no fragmentation necessary
        c->dequeue();
      }
    }

    if (mac_->getNodeType()==STA_BS) {
      txtime = phy->getTrxTime (ch->size(), mac_->getMap()->getDlSubframe()->getProfile (b->getIUC())->getEncoding());
      txtime2 = phy->getTrxSymbolTime (b_data+ch->size(), mac_->getMap()->getDlSubframe()->getProfile (b->getIUC())->getEncoding());
    }
    else {
      txtime = phy->getTrxTime (ch->size(), mac_->getMap()->getUlSubframe()->getProfile (b->getIUC())->getEncoding());
      txtime2 = phy->getTrxSymbolTime (b_data+ch->size(), mac_->getMap()->getUlSubframe()->getProfile (b->getIUC())->getEncoding());
    }
    ch->txtime() = txtime;
    txtime_s = (int)round (txtime2/phy->getSymbolTime ()); //in units of symbol
    //printf ("symbtime=%f\n", phy->getSymbolTime ());
    //printf ("Check packet to send: size=%d txtime=%f(%d) duration=%d(%f)\n", ch->size(),txtime, txtime_s, b->getDuration(), b->getDuration()*phy->getSymbolTime ());
    assert ( txtime2 <= b->getDuration()*phy->getSymbolTime () );
    //printf ("transfert to burst (txtime=%f, txtime2=%f, bduration=%f)\n", txtime,txtime2,b->getDuration()*phy->getSymbolTime ());
    //p = c->dequeue();   //dequeue connection queue
    b->enqueue(p);      //enqueue into burst
    b_data += ch->size(); //increment amount of data enqueued
    if (!pkt_transfered && mac_->getNodeType()!=STA_BS){ //if we transfert at least one packet, remove bw request
      pkt_transfered = true;
      mac_->getMap()->getUlSubframe()->getBw_req()->removeRequest (c->get_cid());
    }
    p = c->get_queue()->head(); //get new head
  }
  return b_data;
}