X86: Make the timing simple CPU handle variable length instructions.
[gem5.git] / src / cpu / base.cc
1 /*
2 * Copyright (c) 2002-2005 The Regents of The University of Michigan
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 * Authors: Steve Reinhardt
29 * Nathan Binkert
30 */
31
32 #include <iostream>
33 #include <string>
34 #include <sstream>
35
36 #include "base/cprintf.hh"
37 #include "base/loader/symtab.hh"
38 #include "base/misc.hh"
39 #include "base/output.hh"
40 #include "base/trace.hh"
41 #include "cpu/base.hh"
42 #include "cpu/cpuevent.hh"
43 #include "cpu/thread_context.hh"
44 #include "cpu/profile.hh"
45 #include "params/BaseCPU.hh"
46 #include "sim/sim_exit.hh"
47 #include "sim/process.hh"
48 #include "sim/sim_events.hh"
49 #include "sim/system.hh"
50
51 // Hack
52 #include "sim/stat_control.hh"
53
54 using namespace std;
55
56 vector<BaseCPU *> BaseCPU::cpuList;
57
58 // This variable reflects the max number of threads in any CPU. Be
59 // careful to only use it once all the CPUs that you care about have
60 // been initialized
61 int maxThreadsPerCPU = 1;
62
63 CPUProgressEvent::CPUProgressEvent(BaseCPU *_cpu, Tick ival)
64 : Event(Event::Progress_Event_Pri), interval(ival), lastNumInst(0),
65 cpu(_cpu)
66 {
67 if (interval)
68 cpu->schedule(this, curTick + interval);
69 }
70
71 void
72 CPUProgressEvent::process()
73 {
74 Counter temp = cpu->totalInstructions();
75 #ifndef NDEBUG
76 double ipc = double(temp - lastNumInst) / (interval / cpu->ticks(1));
77
78 DPRINTFN("%s progress event, instructions committed: %lli, IPC: %0.8d\n",
79 cpu->name(), temp - lastNumInst, ipc);
80 ipc = 0.0;
81 #else
82 cprintf("%lli: %s progress event, instructions committed: %lli\n",
83 curTick, cpu->name(), temp - lastNumInst);
84 #endif
85 lastNumInst = temp;
86 cpu->schedule(this, curTick + interval);
87 }
88
89 const char *
90 CPUProgressEvent::description() const
91 {
92 return "CPU Progress";
93 }
94
95 #if FULL_SYSTEM
96 BaseCPU::BaseCPU(Params *p)
97 : MemObject(p), clock(p->clock), instCnt(0), _cpuId(p->cpu_id),
98 interrupts(p->interrupts),
99 number_of_threads(p->numThreads), system(p->system),
100 phase(p->phase)
101 #else
102 BaseCPU::BaseCPU(Params *p)
103 : MemObject(p), clock(p->clock), _cpuId(p->cpu_id),
104 number_of_threads(p->numThreads), system(p->system),
105 phase(p->phase)
106 #endif
107 {
108 // currentTick = curTick;
109
110 // if Python did not provide a valid ID, do it here
111 if (_cpuId == -1 ) {
112 _cpuId = cpuList.size();
113 }
114
115 // add self to global list of CPUs
116 cpuList.push_back(this);
117
118 DPRINTF(SyscallVerbose, "Constructing CPU with id %d\n", _cpuId);
119
120 if (number_of_threads > maxThreadsPerCPU)
121 maxThreadsPerCPU = number_of_threads;
122
123 // allocate per-thread instruction-based event queues
124 comInstEventQueue = new EventQueue *[number_of_threads];
125 for (int i = 0; i < number_of_threads; ++i)
126 comInstEventQueue[i] = new EventQueue("instruction-based event queue");
127
128 //
129 // set up instruction-count-based termination events, if any
130 //
131 if (p->max_insts_any_thread != 0) {
132 const char *cause = "a thread reached the max instruction count";
133 for (int i = 0; i < number_of_threads; ++i) {
134 Event *event = new SimLoopExitEvent(cause, 0);
135 comInstEventQueue[i]->schedule(event, p->max_insts_any_thread);
136 }
137 }
138
139 if (p->max_insts_all_threads != 0) {
140 const char *cause = "all threads reached the max instruction count";
141
142 // allocate & initialize shared downcounter: each event will
143 // decrement this when triggered; simulation will terminate
144 // when counter reaches 0
145 int *counter = new int;
146 *counter = number_of_threads;
147 for (int i = 0; i < number_of_threads; ++i) {
148 Event *event = new CountedExitEvent(cause, *counter);
149 comInstEventQueue[i]->schedule(event, p->max_insts_any_thread);
150 }
151 }
152
153 // allocate per-thread load-based event queues
154 comLoadEventQueue = new EventQueue *[number_of_threads];
155 for (int i = 0; i < number_of_threads; ++i)
156 comLoadEventQueue[i] = new EventQueue("load-based event queue");
157
158 //
159 // set up instruction-count-based termination events, if any
160 //
161 if (p->max_loads_any_thread != 0) {
162 const char *cause = "a thread reached the max load count";
163 for (int i = 0; i < number_of_threads; ++i) {
164 Event *event = new SimLoopExitEvent(cause, 0);
165 comLoadEventQueue[i]->schedule(event, p->max_loads_any_thread);
166 }
167 }
168
169 if (p->max_loads_all_threads != 0) {
170 const char *cause = "all threads reached the max load count";
171 // allocate & initialize shared downcounter: each event will
172 // decrement this when triggered; simulation will terminate
173 // when counter reaches 0
174 int *counter = new int;
175 *counter = number_of_threads;
176 for (int i = 0; i < number_of_threads; ++i) {
177 Event *event = new CountedExitEvent(cause, *counter);
178 comLoadEventQueue[i]->schedule(event, p->max_loads_all_threads);
179 }
180 }
181
182 functionTracingEnabled = false;
183 if (p->function_trace) {
184 functionTraceStream = simout.find(csprintf("ftrace.%s", name()));
185 currentFunctionStart = currentFunctionEnd = 0;
186 functionEntryTick = p->function_trace_start;
187
188 if (p->function_trace_start == 0) {
189 functionTracingEnabled = true;
190 } else {
191 typedef EventWrapper<BaseCPU, &BaseCPU::enableFunctionTrace> wrap;
192 Event *event = new wrap(this, true);
193 schedule(event, p->function_trace_start);
194 }
195 }
196 #if FULL_SYSTEM
197 profileEvent = NULL;
198 if (params()->profile)
199 profileEvent = new ProfileEvent(this, params()->profile);
200 #endif
201 tracer = params()->tracer;
202 }
203
204 void
205 BaseCPU::enableFunctionTrace()
206 {
207 functionTracingEnabled = true;
208 }
209
210 BaseCPU::~BaseCPU()
211 {
212 }
213
214 void
215 BaseCPU::init()
216 {
217 if (!params()->defer_registration)
218 registerThreadContexts();
219 }
220
221 void
222 BaseCPU::startup()
223 {
224 #if FULL_SYSTEM
225 if (!params()->defer_registration && profileEvent)
226 schedule(profileEvent, curTick);
227 #endif
228
229 if (params()->progress_interval) {
230 Tick num_ticks = ticks(params()->progress_interval);
231 Event *event = new CPUProgressEvent(this, num_ticks);
232 schedule(event, curTick + num_ticks);
233 }
234 }
235
236
237 void
238 BaseCPU::regStats()
239 {
240 using namespace Stats;
241
242 numCycles
243 .name(name() + ".numCycles")
244 .desc("number of cpu cycles simulated")
245 ;
246
247 int size = threadContexts.size();
248 if (size > 1) {
249 for (int i = 0; i < size; ++i) {
250 stringstream namestr;
251 ccprintf(namestr, "%s.ctx%d", name(), i);
252 threadContexts[i]->regStats(namestr.str());
253 }
254 } else if (size == 1)
255 threadContexts[0]->regStats(name());
256
257 #if FULL_SYSTEM
258 #endif
259 }
260
261 Tick
262 BaseCPU::nextCycle()
263 {
264 Tick next_tick = curTick - phase + clock - 1;
265 next_tick -= (next_tick % clock);
266 next_tick += phase;
267 return next_tick;
268 }
269
270 Tick
271 BaseCPU::nextCycle(Tick begin_tick)
272 {
273 Tick next_tick = begin_tick;
274 if (next_tick % clock != 0)
275 next_tick = next_tick - (next_tick % clock) + clock;
276 next_tick += phase;
277
278 assert(next_tick >= curTick);
279 return next_tick;
280 }
281
282 void
283 BaseCPU::registerThreadContexts()
284 {
285 for (int i = 0; i < threadContexts.size(); ++i) {
286 ThreadContext *tc = threadContexts[i];
287
288 /** This is so that contextId and cpuId match where there is a
289 * 1cpu:1context relationship. Otherwise, the order of registration
290 * could affect the assignment and cpu 1 could have context id 3, for
291 * example. We may even want to do something like this for SMT so that
292 * cpu 0 has the lowest thread contexts and cpu N has the highest, but
293 * I'll just do this for now
294 */
295 if (number_of_threads == 1)
296 tc->setContextId(system->registerThreadContext(tc, _cpuId));
297 else
298 tc->setContextId(system->registerThreadContext(tc));
299 #if !FULL_SYSTEM
300 tc->getProcessPtr()->assignThreadContext(tc->contextId());
301 #endif
302 }
303 }
304
305
306 int
307 BaseCPU::findContext(ThreadContext *tc)
308 {
309 for (int i = 0; i < threadContexts.size(); ++i) {
310 if (tc == threadContexts[i])
311 return i;
312 }
313 return 0;
314 }
315
316 void
317 BaseCPU::switchOut()
318 {
319 // panic("This CPU doesn't support sampling!");
320 #if FULL_SYSTEM
321 if (profileEvent && profileEvent->scheduled())
322 deschedule(profileEvent);
323 #endif
324 }
325
326 void
327 BaseCPU::takeOverFrom(BaseCPU *oldCPU, Port *ic, Port *dc)
328 {
329 assert(threadContexts.size() == oldCPU->threadContexts.size());
330
331 _cpuId = oldCPU->cpuId();
332
333 for (int i = 0; i < threadContexts.size(); ++i) {
334 ThreadContext *newTC = threadContexts[i];
335 ThreadContext *oldTC = oldCPU->threadContexts[i];
336
337 newTC->takeOverFrom(oldTC);
338
339 CpuEvent::replaceThreadContext(oldTC, newTC);
340
341 assert(newTC->contextId() == oldTC->contextId());
342 assert(newTC->threadId() == oldTC->threadId());
343 system->replaceThreadContext(newTC, newTC->contextId());
344
345 if (DTRACE(Context))
346 ThreadContext::compare(oldTC, newTC);
347 }
348
349 #if FULL_SYSTEM
350 interrupts = oldCPU->interrupts;
351
352 for (int i = 0; i < threadContexts.size(); ++i)
353 threadContexts[i]->profileClear();
354
355 if (profileEvent)
356 schedule(profileEvent, curTick);
357 #endif
358
359 // Connect new CPU to old CPU's memory only if new CPU isn't
360 // connected to anything. Also connect old CPU's memory to new
361 // CPU.
362 if (!ic->isConnected()) {
363 Port *peer = oldCPU->getPort("icache_port")->getPeer();
364 ic->setPeer(peer);
365 peer->setPeer(ic);
366 }
367
368 if (!dc->isConnected()) {
369 Port *peer = oldCPU->getPort("dcache_port")->getPeer();
370 dc->setPeer(peer);
371 peer->setPeer(dc);
372 }
373 }
374
375
376 #if FULL_SYSTEM
377 BaseCPU::ProfileEvent::ProfileEvent(BaseCPU *_cpu, Tick _interval)
378 : cpu(_cpu), interval(_interval)
379 { }
380
381 void
382 BaseCPU::ProfileEvent::process()
383 {
384 for (int i = 0, size = cpu->threadContexts.size(); i < size; ++i) {
385 ThreadContext *tc = cpu->threadContexts[i];
386 tc->profileSample();
387 }
388
389 cpu->schedule(this, curTick + interval);
390 }
391
392 void
393 BaseCPU::postInterrupt(int int_num, int index)
394 {
395 interrupts->post(int_num, index);
396 }
397
398 void
399 BaseCPU::clearInterrupt(int int_num, int index)
400 {
401 interrupts->clear(int_num, index);
402 }
403
404 void
405 BaseCPU::clearInterrupts()
406 {
407 interrupts->clearAll();
408 }
409
410 void
411 BaseCPU::serialize(std::ostream &os)
412 {
413 SERIALIZE_SCALAR(instCnt);
414 interrupts->serialize(os);
415 }
416
417 void
418 BaseCPU::unserialize(Checkpoint *cp, const std::string &section)
419 {
420 UNSERIALIZE_SCALAR(instCnt);
421 interrupts->unserialize(cp, section);
422 }
423
424 #endif // FULL_SYSTEM
425
426 void
427 BaseCPU::traceFunctionsInternal(Addr pc)
428 {
429 if (!debugSymbolTable)
430 return;
431
432 // if pc enters different function, print new function symbol and
433 // update saved range. Otherwise do nothing.
434 if (pc < currentFunctionStart || pc >= currentFunctionEnd) {
435 string sym_str;
436 bool found = debugSymbolTable->findNearestSymbol(pc, sym_str,
437 currentFunctionStart,
438 currentFunctionEnd);
439
440 if (!found) {
441 // no symbol found: use addr as label
442 sym_str = csprintf("0x%x", pc);
443 currentFunctionStart = pc;
444 currentFunctionEnd = pc + 1;
445 }
446
447 ccprintf(*functionTraceStream, " (%d)\n%d: %s",
448 curTick - functionEntryTick, curTick, sym_str);
449 functionEntryTick = curTick;
450 }
451 }