1/*
2 * Copyright (c) 2012-2013, 2016-2018 ARM Limited
3 * All rights reserved
4 *
5 * The license below extends only to copyright in the software and shall
6 * not be construed as granting a license to any other intellectual
7 * property including but not limited to intellectual property relating
8 * to a hardware implementation of the functionality of the software
9 * licensed hereunder. You may use the software subject to the license
10 * terms below provided that you ensure that this notice is replicated
11 * unmodified and in its entirety in all distributions of the software,
12 * modified or unmodified, in source code or in binary form.
13 *
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions are
16 * met: redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer;
18 * redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution;
21 * neither the name of the copyright holders nor the names of its
22 * contributors may be used to endorse or promote products derived from
23 * this software without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
26 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
27 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
28 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
29 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
31 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
35 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 *
37 * Authors: Thomas Grass
38 * Andreas Hansson
39 * Sascha Bischoff
40 */
41#include "cpu/testers/traffic_gen/base.hh"
42
43#include <sstream>
44
45#include "base/intmath.hh"
46#include "base/random.hh"
47#include "cpu/testers/traffic_gen/base_gen.hh"
48#include "debug/Checkpoint.hh"
49#include "debug/TrafficGen.hh"
50#include "params/BaseTrafficGen.hh"
51#include "sim/sim_exit.hh"
52#include "sim/stats.hh"
53#include "sim/system.hh"
54
55using namespace std;
56
57BaseTrafficGen::BaseTrafficGen(const BaseTrafficGenParams* p)
58 : MemObject(p),
59 system(p->system),
60 elasticReq(p->elastic_req),
61 progressCheck(p->progress_check),
62 noProgressEvent([this]{ noProgress(); }, name()),
63 nextTransitionTick(0),
64 nextPacketTick(0),
65 port(name() + ".port", *this),
66 retryPkt(NULL),
67 retryPktTick(0),
68 updateEvent([this]{ update(); }, name()),
69 numSuppressed(0),
70 masterID(system->getMasterId(this))
71{
72}
73
74BaseMasterPort&
75BaseTrafficGen::getMasterPort(const string& if_name, PortID idx)
76{
77 if (if_name == "port") {
78 return port;
79 } else {
80 return MemObject::getMasterPort(if_name, idx);
81 }
82}
83
84void
85BaseTrafficGen::init()
86{
87 MemObject::init();
88
89 if (!port.isConnected())
90 fatal("The port of %s is not connected!\n", name());
91}
92
93DrainState
94BaseTrafficGen::drain()
95{
96 if (!updateEvent.scheduled()) {
97 // no event has been scheduled yet (e.g. switched from atomic mode)
98 return DrainState::Drained;
99 }
100
101 if (retryPkt == NULL) {
102 // shut things down
103 nextPacketTick = MaxTick;
104 nextTransitionTick = MaxTick;
105 deschedule(updateEvent);
106 return DrainState::Drained;
107 } else {
108 return DrainState::Draining;
109 }
110}
111
112void
113BaseTrafficGen::serialize(CheckpointOut &cp) const
114{
115 DPRINTF(Checkpoint, "Serializing BaseTrafficGen\n");
116
117 // save ticks of the graph event if it is scheduled
118 Tick nextEvent = updateEvent.scheduled() ? updateEvent.when() : 0;
119
120 DPRINTF(TrafficGen, "Saving nextEvent=%llu\n", nextEvent);
121
122 SERIALIZE_SCALAR(nextEvent);
123
124 SERIALIZE_SCALAR(nextTransitionTick);
125
126 SERIALIZE_SCALAR(nextPacketTick);
127}
128
129void
130BaseTrafficGen::unserialize(CheckpointIn &cp)
131{
132 // restore scheduled events
133 Tick nextEvent;
134 UNSERIALIZE_SCALAR(nextEvent);
135 if (nextEvent != 0)
136 schedule(updateEvent, nextEvent);
137
138 UNSERIALIZE_SCALAR(nextTransitionTick);
139
140 UNSERIALIZE_SCALAR(nextPacketTick);
141}
142
143void
144BaseTrafficGen::update()
145{
146 // shift our progress-tracking event forward
147 reschedule(noProgressEvent, curTick() + progressCheck, true);
148
149 // if we have reached the time for the next state transition, then
150 // perform the transition
151 if (curTick() >= nextTransitionTick) {
152 transition();
153 } else {
154 assert(curTick() >= nextPacketTick);
155 // get the next packet and try to send it
156 PacketPtr pkt = activeGenerator->getNextPacket();
157
158 // suppress packets that are not destined for a memory, such as
159 // device accesses that could be part of a trace
160 if (system->isMemAddr(pkt->getAddr())) {
161 numPackets++;
162 if (!port.sendTimingReq(pkt)) {
163 retryPkt = pkt;
164 retryPktTick = curTick();
165 }
166 } else {
167 DPRINTF(TrafficGen, "Suppressed packet %s 0x%x\n",
168 pkt->cmdString(), pkt->getAddr());
169
170 ++numSuppressed;
171 if (numSuppressed % 10000)
172 warn("%s suppressed %d packets with non-memory addresses\n",
173 name(), numSuppressed);
174
175 delete pkt;
176 pkt = nullptr;
177 }
178 }
179
180 // if we are waiting for a retry, do not schedule any further
181 // events, in the case of a transition or a successful send, go
182 // ahead and determine when the next update should take place
183 if (retryPkt == NULL) {
184 nextPacketTick = activeGenerator->nextPacketTick(elasticReq, 0);
185 scheduleUpdate();
186 }
187}
188
189void
190BaseTrafficGen::transition()
191{
192 if (activeGenerator)
193 activeGenerator->exit();
194
195 activeGenerator = nextGenerator();
196
197 if (activeGenerator) {
198 const Tick duration = activeGenerator->duration;
199 if (duration != MaxTick && duration != 0) {
200 // we could have been delayed and not transitioned on the
201 // exact tick when we were supposed to (due to back
202 // pressure when sending a packet)
203 nextTransitionTick = curTick() + duration;
204 } else {
205 nextTransitionTick = MaxTick;
206 }
207
208 activeGenerator->enter();
209 nextPacketTick = activeGenerator->nextPacketTick(elasticReq, 0);
210 } else {
211 nextPacketTick = MaxTick;
212 nextTransitionTick = MaxTick;
213 assert(!updateEvent.scheduled());
214 }
215}
216
217void
218BaseTrafficGen::scheduleUpdate()
219{
220 // schedule next update event based on either the next execute
221 // tick or the next transition, which ever comes first
222 const Tick nextEventTick = std::min(nextPacketTick, nextTransitionTick);
223 if (nextEventTick == MaxTick)
224 return;
225
226 DPRINTF(TrafficGen, "Next event scheduled at %lld\n", nextEventTick);
227
228 // The next transition tick may be in the past if there was a
229 // retry, so ensure that we don't schedule anything in the past.
230 schedule(updateEvent, std::max(curTick(), nextEventTick));
231}
232
233void
234BaseTrafficGen::start()
235{
236 transition();
237 scheduleUpdate();
238}
239
240void
241BaseTrafficGen::recvReqRetry()
242{
243 assert(retryPkt != NULL);
244
245 DPRINTF(TrafficGen, "Received retry\n");
246 numRetries++;
247 // attempt to send the packet, and if we are successful start up
248 // the machinery again
249 if (port.sendTimingReq(retryPkt)) {
250 retryPkt = NULL;
251 // remember how much delay was incurred due to back-pressure
252 // when sending the request, we also use this to derive
253 // the tick for the next packet
254 Tick delay = curTick() - retryPktTick;
255 retryPktTick = 0;
256 retryTicks += delay;
257
258 if (drainState() != DrainState::Draining) {
259 // packet is sent, so find out when the next one is due
260 nextPacketTick = activeGenerator->nextPacketTick(elasticReq,
261 delay);
262 scheduleUpdate();
263 } else {
264 // shut things down
265 nextPacketTick = MaxTick;
266 nextTransitionTick = MaxTick;
267 signalDrainDone();
268 }
269 }
270}
271
272void
273BaseTrafficGen::noProgress()
274{
275 fatal("BaseTrafficGen %s spent %llu ticks without making progress",
276 name(), progressCheck);
277}
278
279void
280BaseTrafficGen::regStats()
281{
282 ClockedObject::regStats();
283
284 // Initialise all the stats
285 using namespace Stats;
286
287 numPackets
288 .name(name() + ".numPackets")
289 .desc("Number of packets generated");
290
291 numRetries
292 .name(name() + ".numRetries")
293 .desc("Number of retries");
294
295 retryTicks
296 .name(name() + ".retryTicks")
297 .desc("Time spent waiting due to back-pressure (ticks)");
298}
299
300bool
301BaseTrafficGen::TrafficGenPort::recvTimingResp(PacketPtr pkt)
302{
303 delete pkt;
304
305 return true;
306}