src/learning_gem5/part2/goodbye_object.cc

   1 /*
   2  * Copyright (c) 2017 Jason Lowe-Power
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met: redistributions of source code must retain the above copyright
   8  * notice, this list of conditions and the following disclaimer;
   9  * redistributions in binary form must reproduce the above copyright
  10  * notice, this list of conditions and the following disclaimer in the
  11  * documentation and/or other materials provided with the distribution;
  12  * neither the name of the copyright holders nor the names of its
  13  * contributors may be used to endorse or promote products derived from
  14  * this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  19  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  20  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #include "learning_gem5/part2/goodbye_object.hh"
  30
  31 #include "debug/HelloExample.hh"
  32 #include "sim/sim_exit.hh"
  33
  34 GoodbyeObject::GoodbyeObject(GoodbyeObjectParams *params) :
  35     SimObject(params), event([this]{ processEvent(); }, name() + ".event"),
  36     bandwidth(params->write_bandwidth), bufferSize(params->buffer_size),
  37     buffer(nullptr), bufferUsed(0)
  38 {
  39     buffer = new char[bufferSize];
  40     DPRINTF(HelloExample, "Created the goodbye object\n");
  41 }
  42
  43 GoodbyeObject::~GoodbyeObject()
  44 {
  45     delete[] buffer;
  46 }
  47
  48 void
  49 GoodbyeObject::processEvent()
  50 {
  51     DPRINTF(HelloExample, "Processing the event!\n");
  52
  53     // Actually do the "work" of the event
  54     fillBuffer();
  55 }
  56
  57 void
  58 GoodbyeObject::sayGoodbye(std::string other_name)
  59 {
  60     DPRINTF(HelloExample, "Saying goodbye to %s\n", other_name);
  61
  62     message = "Goodbye " + other_name + "!! ";
  63
  64     // Kick off the the first buffer fill. If it can't fill the whole buffer
  65     // because of a limited bandwidth, then this function will schedule another
  66     // event to finish the fill
  67     fillBuffer();
  68 }
  69
  70 void
  71 GoodbyeObject::fillBuffer()
  72 {
  73     // There better be a message
  74     assert(message.length() > 0);
  75
  76     // Copy from the message to the buffer per byte.
  77     int bytes_copied = 0;
  78     for (auto it = message.begin();
  79          it < message.end() && bufferUsed < bufferSize - 1;
  80          it++, bufferUsed++, bytes_copied++) {
  81         // Copy the character into the buffer
  82         buffer[bufferUsed] = *it;
  83     }
  84
  85     if (bufferUsed < bufferSize - 1) {
  86         // Wait for the next copy for as long as it would have taken
  87         DPRINTF(HelloExample, "Scheduling another fillBuffer in %d ticks\n",
  88                 bandwidth * bytes_copied);
  89         schedule(event, curTick() + bandwidth * bytes_copied);
  90     } else {
  91         DPRINTF(HelloExample, "Goodbye done copying!\n");
  92         // Be sure to take into account the time for the last bytes
  93         exitSimLoop(buffer, 0, curTick() + bandwidth * bytes_copied);
  94     }
  95 }
  96
  97 GoodbyeObject*
  98 GoodbyeObjectParams::create()
  99 {
 100     return new GoodbyeObject(this);
 101 }