Transaction Data Pointer

[noay]

What is the correct way to handle transaction data pointer (set_data_ptr).
If I free it right after b_transport I get an error since transaction handling isn't completes.
Unlike tlm_extension it is not freed once transaction is completed.
 
 

void rx_thread() {

  while(1)
  {
    uint8_t *buf = new uint8_t[ETH_MAC_PACKET_MAX_LEN];

    tlm::tlm_generic_payload* pkt_trans = new tlm::tlm_generic_payload();
    pkt_trans->set_command(tlm::TLM_WRITE_COMMAND);
    pkt_trans->set_data_length(ETH_MAC_PACKET_MAX_LEN);
    pkt_trans->set_data_ptr((unsigned char *)(buf));
    phy2mac->b_transport(*pkt_trans, delay);

    // Note:not calling "delete [] buf;" here since this data is a part of generic payload now and
    //       shouldn't be destroyed until transaction handling completes! Although b_transport() is
    //       a synchronous call indeed, queue is filled with pointers to original structures rather then to their clones.

  }
}

 

[ralph.goergen]

Hi.

Normally the initiator is considered as owner of the payload, i.e. he should take care of allocating and de-allocating it.

The target should decide how to use the data. If the target wants to keep it/store it, the target should make a copy of the data. In that sense, the transaction is completed when b_transport returns because the initiator transfered it to the target and the target had a chance to handle it.

A benefit of this is that you do not need dynamic allocation of the buffer buf.

 

Greetings

Ralph