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 "base/trace.hh"
  32 #include "debug/HelloExample.hh"
  33 #include "sim/sim_exit.hh"
  34
  35 GoodbyeObject::GoodbyeObject(GoodbyeObjectParams *params) :
  36     SimObject(params), event([this]{ processEvent(); }, name() + ".event"),
  37     bandwidth(params->write_bandwidth), bufferSize(params->buffer_size),
  38     buffer(nullptr), bufferUsed(0)
  39 {
  40     buffer = new char[bufferSize]();
  41     DPRINTF(HelloExample, "Created the goodbye object\n");
  42 }
  43
  44 GoodbyeObject::~GoodbyeObject()
  45 {
  46     delete[] buffer;
  47 }
  48
  49 void
  50 GoodbyeObject::processEvent()
  51 {
  52     DPRINTF(HelloExample, "Processing the event!\n");
  53
  54     // Actually do the "work" of the event
  55     fillBuffer();
  56 }
  57
  58 void
  59 GoodbyeObject::sayGoodbye(std::string other_name)
  60 {
  61     DPRINTF(HelloExample, "Saying goodbye to %s\n", other_name);
  62
  63     message = "Goodbye " + other_name + "!! ";
  64
  65     // Kick off the the first buffer fill. If it can't fill the whole buffer
  66     // because of a limited bandwidth, then this function will schedule another
  67     // event to finish the fill
  68     fillBuffer();
  69 }
  70
  71 void
  72 GoodbyeObject::fillBuffer()
  73 {
  74     // There better be a message
  75     assert(message.length() > 0);
  76
  77     // Copy from the message to the buffer per byte.
  78     int bytes_copied = 0;
  79     for (auto it = message.begin();
  80          it < message.end() && bufferUsed < bufferSize - 1;
  81          it++, bufferUsed++, bytes_copied++) {
  82         // Copy the character into the buffer
  83         buffer[bufferUsed] = *it;
  84     }
  85
  86     if (bufferUsed < bufferSize - 1) {
  87         // Wait for the next copy for as long as it would have taken
  88         DPRINTF(HelloExample, "Scheduling another fillBuffer in %d ticks\n",
  89                 bandwidth * bytes_copied);
  90         schedule(event, curTick() + bandwidth * bytes_copied);
  91     } else {
  92         DPRINTF(HelloExample, "Goodbye done copying!\n");
  93         // Be sure to take into account the time for the last bytes
  94         exitSimLoop(buffer, 0, curTick() + bandwidth * bytes_copied);
  95     }
  96 }
  97
  98 GoodbyeObject*
  99 GoodbyeObjectParams::create()
 100 {
 101     return new GoodbyeObject(this);
 102 }