1/* 2 * Copyright (c) 2000-2005 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/* @file 33 * EventQueue interfaces 34 */ 35 36#ifndef __SIM_EVENTQ_HH__ 37#define __SIM_EVENTQ_HH__ 38 39#include <algorithm> 40#include <cassert> 41#include <climits> 42#include <iosfwd> 43#include <string> 44 45#include "base/fast_alloc.hh" 46#include "base/flags.hh" 47#include "base/misc.hh" 48#include "base/trace.hh" 49#include "base/types.hh" 50#include "sim/serialize.hh" 51 52class EventQueue; // forward declaration 53 54extern EventQueue mainEventQueue; 55 56/* 57 * An item on an event queue. The action caused by a given 58 * event is specified by deriving a subclass and overriding the 59 * process() member function. 60 * 61 * Caution, the order of members is chosen to maximize data packing. 62 */ 63class Event : public Serializable, public FastAlloc 64{ 65 friend class EventQueue; 66 67 protected: 68 typedef short FlagsType; 69 typedef ::Flags<FlagsType> Flags; 70 71 static const FlagsType PublicRead = 0x003f; 72 static const FlagsType PublicWrite = 0x001d; 73 static const FlagsType Squashed = 0x0001; 74 static const FlagsType Scheduled = 0x0002; 75 static const FlagsType AutoDelete = 0x0004; 76 static const FlagsType AutoSerialize = 0x0008; 77 static const FlagsType IsExitEvent = 0x0010; 78 static const FlagsType IsMainQueue = 0x0020; 79#ifdef EVENTQ_DEBUG 80 static const FlagsType Initialized = 0xf000; 81#endif 82 83 private: 84 // The event queue is now a linked list of linked lists. The 85 // 'nextBin' pointer is to find the bin, where a bin is defined as 86 // when+priority. All events in the same bin will be stored in a 87 // second linked list (a stack) maintained by the 'nextInBin' 88 // pointer. The list will be accessed in LIFO order. The end 89 // result is that the insert/removal in 'nextBin' is 90 // linear/constant, and the lookup/removal in 'nextInBin' is 91 // constant/constant. Hopefully this is a significant improvement 92 // over the current fully linear insertion. 93 Event *nextBin; 94 Event *nextInBin; 95 96 static Event *insertBefore(Event *event, Event *curr); 97 static Event *removeItem(Event *event, Event *last); 98 99 Tick _when; //!< timestamp when event should be processed 100 short _priority; //!< event priority 101 Flags flags; 102 103#ifndef NDEBUG 104 /// Global counter to generate unique IDs for Event instances 105 static Counter instanceCounter; 106 107 /// This event's unique ID. We can also use pointer values for 108 /// this but they're not consistent across runs making debugging 109 /// more difficult. Thus we use a global counter value when 110 /// debugging. 111 Counter instance; 112 113 /// queue to which this event belongs (though it may or may not be 114 /// scheduled on this queue yet) 115 EventQueue *queue; 116#endif 117 118#ifdef EVENTQ_DEBUG 119 Tick whenCreated; //!< time created 120 Tick whenScheduled; //!< time scheduled 121#endif 122 123 void 124 setWhen(Tick when, EventQueue *q) 125 { 126 _when = when; 127#ifndef NDEBUG 128 queue = q; 129#endif 130#ifdef EVENTQ_DEBUG 131 whenScheduled = curTick; 132#endif 133 } 134 135 protected: 136 /// Accessor for flags. 137 Flags 138 getFlags() const 139 { 140 return flags & PublicRead; 141 } 142 143 Flags 144 getFlags(Flags _flags) const 145 { 146 assert(flags.noneSet(~PublicRead)); 147 return flags.isSet(_flags); 148 } 149 150 Flags 151 allFlags(Flags _flags) const 152 { 153 assert(_flags.noneSet(~PublicRead)); 154 return flags.allSet(_flags); 155 } 156 157 /// Accessor for flags. 158 void 159 setFlags(Flags _flags) 160 { 161 assert(_flags.noneSet(~PublicWrite)); 162 flags.set(_flags); 163 } 164 165 void 166 clearFlags(Flags _flags) 167 { 168 assert(_flags.noneSet(~PublicWrite)); 169 flags.clear(_flags); 170 } 171 172 void 173 clearFlags() 174 { 175 flags.clear(PublicWrite); 176 } 177 178 // This function isn't really useful if TRACING_ON is not defined 179 virtual void trace(const char *action); //!< trace event activity 180 181 public: 182 /// Event priorities, to provide tie-breakers for events scheduled 183 /// at the same cycle. Most events are scheduled at the default 184 /// priority; these values are used to control events that need to 185 /// be ordered within a cycle. 186 enum Priority { 187 /// Minimum priority 188 Minimum_Pri = SHRT_MIN, 189 190 /// If we enable tracing on a particular cycle, do that as the 191 /// very first thing so we don't miss any of the events on 192 /// that cycle (even if we enter the debugger). 193 Trace_Enable_Pri = -101, 194 195 /// Breakpoints should happen before anything else (except 196 /// enabling trace output), so we don't miss any action when 197 /// debugging. 198 Debug_Break_Pri = -100, 199 200 /// CPU switches schedule the new CPU's tick event for the 201 /// same cycle (after unscheduling the old CPU's tick event). 202 /// The switch needs to come before any tick events to make 203 /// sure we don't tick both CPUs in the same cycle. 204 CPU_Switch_Pri = -31, 205 206 /// For some reason "delayed" inter-cluster writebacks are 207 /// scheduled before regular writebacks (which have default 208 /// priority). Steve? 209 Delayed_Writeback_Pri = -1, 210 211 /// Default is zero for historical reasons. 212 Default_Pri = 0, 213 214 /// Serailization needs to occur before tick events also, so 215 /// that a serialize/unserialize is identical to an on-line 216 /// CPU switch. 217 Serialize_Pri = 32, 218 219 /// CPU ticks must come after other associated CPU events 220 /// (such as writebacks). 221 CPU_Tick_Pri = 50, 222 223 /// Statistics events (dump, reset, etc.) come after 224 /// everything else, but before exit. 225 Stat_Event_Pri = 90, 226 227 /// Progress events come at the end. 228 Progress_Event_Pri = 95, 229 230 /// If we want to exit on this cycle, it's the very last thing 231 /// we do. 232 Sim_Exit_Pri = 100, 233 234 /// Maximum priority 235 Maximum_Pri = SHRT_MAX 236 }; 237 238 /* 239 * Event constructor 240 * @param queue that the event gets scheduled on 241 */ 242 Event(Priority p = Default_Pri) 243 : nextBin(NULL), nextInBin(NULL), _priority(p) 244 { 245#ifndef NDEBUG 246 instance = ++instanceCounter; 247 queue = NULL; 248#endif 249#ifdef EVENTQ_DEBUG 250 flags.set(Initialized); 251 whenCreated = curTick; 252 whenScheduled = 0; 253#endif 254 } 255 256 virtual ~Event(); 257 virtual const std::string name() const; 258 259 /// Return a C string describing the event. This string should 260 /// *not* be dynamically allocated; just a const char array 261 /// describing the event class. 262 virtual const char *description() const; 263 264 /// Dump the current event data 265 void dump() const; 266 267 public: 268 /* 269 * This member function is invoked when the event is processed 270 * (occurs). There is no default implementation; each subclass 271 * must provide its own implementation. The event is not 272 * automatically deleted after it is processed (to allow for 273 * statically allocated event objects). 274 * 275 * If the AutoDestroy flag is set, the object is deleted once it 276 * is processed. 277 */ 278 virtual void process() = 0; 279 280 /// Determine if the current event is scheduled 281 bool scheduled() const { return flags.isSet(Scheduled); } 282 283 /// Squash the current event 284 void squash() { flags.set(Squashed); } 285 286 /// Check whether the event is squashed 287 bool squashed() const { return flags.isSet(Squashed); } 288 289 /// See if this is a SimExitEvent (without resorting to RTTI) 290 bool isExitEvent() const { return flags.isSet(IsExitEvent); } 291 292 /// Get the time that the event is scheduled 293 Tick when() const { return _when; } 294 295 /// Get the event priority 296 int priority() const { return _priority; } 297 298#ifndef SWIG 299 struct priority_compare 300 : public std::binary_function<Event *, Event *, bool> 301 { 302 bool 303 operator()(const Event *l, const Event *r) const 304 { 305 return l->when() >= r->when() || l->priority() >= r->priority(); 306 } 307 }; 308 309 virtual void serialize(std::ostream &os); 310 virtual void unserialize(Checkpoint *cp, const std::string §ion); 311#endif 312}; 313
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314#ifndef SWIG 315inline bool 316operator<(const Event &l, const Event &r) 317{ 318 return l.when() < r.when() || 319 (l.when() == r.when() && l.priority() < r.priority()); 320} 321 322inline bool 323operator>(const Event &l, const Event &r) 324{ 325 return l.when() > r.when() || 326 (l.when() == r.when() && l.priority() > r.priority()); 327} 328 329inline bool 330operator<=(const Event &l, const Event &r) 331{ 332 return l.when() < r.when() || 333 (l.when() == r.when() && l.priority() <= r.priority()); 334} 335inline bool 336operator>=(const Event &l, const Event &r) 337{ 338 return l.when() > r.when() || 339 (l.when() == r.when() && l.priority() >= r.priority()); 340} 341 342inline bool 343operator==(const Event &l, const Event &r) 344{ 345 return l.when() == r.when() && l.priority() == r.priority(); 346} 347 348inline bool 349operator!=(const Event &l, const Event &r) 350{ 351 return l.when() != r.when() || l.priority() != r.priority(); 352} 353#endif 354 |
355/* 356 * Queue of events sorted in time order 357 */ 358class EventQueue : public Serializable 359{ 360 private: 361 std::string objName; 362 Event *head; 363 364 void insert(Event *event); 365 void remove(Event *event); 366 367 public: 368 EventQueue(const std::string &n) 369 : objName(n), head(NULL) 370 {} 371 372 virtual const std::string name() const { return objName; } 373 374 // schedule the given event on this queue 375 void schedule(Event *event, Tick when); 376 void deschedule(Event *event); 377 void reschedule(Event *event, Tick when, bool always = false); 378 379 Tick nextTick() const { return head->when(); } 380 Event *serviceOne(); 381 382 // process all events up to the given timestamp. we inline a 383 // quick test to see if there are any events to process; if so, 384 // call the internal out-of-line version to process them all. 385 void 386 serviceEvents(Tick when) 387 { 388 while (!empty()) { 389 if (nextTick() > when) 390 break; 391 392 /** 393 * @todo this assert is a good bug catcher. I need to 394 * make it true again. 395 */ 396 //assert(head->when() >= when && "event scheduled in the past"); 397 serviceOne(); 398 } 399 } 400 401 // default: process all events up to 'now' (curTick) 402 void serviceEvents() { serviceEvents(curTick); } 403 404 // return true if no events are queued 405 bool empty() const { return head == NULL; } 406 407 void dump() const; 408 409 Tick nextEventTime() { return empty() ? curTick : head->when(); } 410 411 bool debugVerify() const; 412 413#ifndef SWIG 414 virtual void serialize(std::ostream &os); 415 virtual void unserialize(Checkpoint *cp, const std::string §ion); 416#endif 417}; 418 419#ifndef SWIG 420class EventManager 421{ 422 protected: 423 /** A pointer to this object's event queue */ 424 EventQueue *eventq; 425 426 public: 427 EventManager(EventManager &em) : eventq(em.queue()) {} 428 EventManager(EventManager *em) : eventq(em ? em->queue() : NULL) {} 429 EventManager(EventQueue *eq) : eventq(eq) {} 430 431 EventQueue * 432 queue() const 433 { 434 return eventq; 435 } 436 437 void 438 schedule(Event &event, Tick when) 439 { 440 eventq->schedule(&event, when); 441 } 442 443 void 444 deschedule(Event &event) 445 { 446 eventq->deschedule(&event); 447 } 448 449 void 450 reschedule(Event &event, Tick when, bool always = false) 451 { 452 eventq->reschedule(&event, when, always); 453 } 454 455 void 456 schedule(Event *event, Tick when) 457 { 458 eventq->schedule(event, when); 459 } 460 461 void 462 deschedule(Event *event) 463 { 464 eventq->deschedule(event); 465 } 466 467 void 468 reschedule(Event *event, Tick when, bool always = false) 469 { 470 eventq->reschedule(event, when, always); 471 } 472}; 473
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433template <class T, void (T::* F)()>
434void
435DelayFunction(EventQueue *eventq, Tick when, T *object)
436{
437 class DelayEvent : public Event
438 {
439 private:
440 T *object;
441
442 public:
443 DelayEvent(T *o)
444 : object(o)
445 { this->setFlags(AutoDelete); }
446 void process() { (object->*F)(); }
447 const char *description() const { return "delay"; }
448 };
449
450 eventq->schedule(new DelayEvent(object), when);
451}
452
453template <class T, void (T::* F)()>
454class EventWrapper : public Event
455{
456 private:
457 T *object;
458
459 public:
460 EventWrapper(T *obj, bool del = false, Priority p = Default_Pri)
461 : Event(p), object(obj)
462 {
463 if (del)
464 setFlags(AutoDelete);
465 }
466
467 void process() { (object->*F)(); }
468
469 const std::string
470 name() const
471 {
472 return object->name() + ".wrapped_event";
473 }
474
475 const char *description() const { return "EventWrapped"; }
476};
477
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474inline void 475EventQueue::schedule(Event *event, Tick when) 476{ 477 assert((UTick)when >= (UTick)curTick); 478 assert(!event->scheduled()); 479#ifdef EVENTQ_DEBUG 480 assert((event->flags & Event::Initialized) == Event::Initialized); 481#endif 482 483 event->setWhen(when, this); 484 insert(event); 485 event->flags.set(Event::Scheduled); 486 if (this == &mainEventQueue) 487 event->flags.set(Event::IsMainQueue); 488 else 489 event->flags.clear(Event::IsMainQueue); 490 491 if (DTRACE(Event)) 492 event->trace("scheduled"); 493} 494 495inline void 496EventQueue::deschedule(Event *event) 497{ 498 assert(event->scheduled()); 499#ifdef EVENTQ_DEBUG 500 assert((event->flags & Event::Initialized) == Event::Initialized); 501#endif 502 503 remove(event); 504 505 event->flags.clear(Event::Squashed); 506 event->flags.clear(Event::Scheduled); 507 508 if (event->flags.isSet(Event::AutoDelete)) 509 delete event; 510 511 if (DTRACE(Event)) 512 event->trace("descheduled"); 513} 514 515inline void 516EventQueue::reschedule(Event *event, Tick when, bool always) 517{ 518 assert(when >= curTick); 519 assert(always || event->scheduled()); 520#ifdef EVENTQ_DEBUG 521 assert((event->flags & Event::Initialized) == Event::Initialized); 522#endif 523 524 if (event->scheduled()) 525 remove(event); 526 527 event->setWhen(when, this); 528 insert(event); 529 event->flags.clear(Event::Squashed); 530 event->flags.set(Event::Scheduled); 531 if (this == &mainEventQueue) 532 event->flags.set(Event::IsMainQueue); 533 else 534 event->flags.clear(Event::IsMainQueue); 535 536 if (DTRACE(Event)) 537 event->trace("rescheduled"); 538} 539
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544inline bool
545operator<(const Event &l, const Event &r)
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540template <class T, void (T::* F)()> 541void 542DelayFunction(EventQueue *eventq, Tick when, T *object) |
543{
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547 return l.when() < r.when() ||
548 (l.when() == r.when() && l.priority() < r.priority());
549}
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544 class DelayEvent : public Event 545 { 546 private: 547 T *object; |
548
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551inline bool
552operator>(const Event &l, const Event &r)
553{
554 return l.when() > r.when() ||
555 (l.when() == r.when() && l.priority() > r.priority());
556}
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549 public: 550 DelayEvent(T *o) 551 : object(o) 552 { this->setFlags(AutoDelete); } 553 void process() { (object->*F)(); } 554 const char *description() const { return "delay"; } 555 }; |
556
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558inline bool
559operator<=(const Event &l, const Event &r)
560{
561 return l.when() < r.when() ||
562 (l.when() == r.when() && l.priority() <= r.priority());
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557 eventq->schedule(new DelayEvent(object), when); |
558}
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564inline bool
565operator>=(const Event &l, const Event &r)
566{
567 return l.when() > r.when() ||
568 (l.when() == r.when() && l.priority() >= r.priority());
569}
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559
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571inline bool
572operator==(const Event &l, const Event &r)
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560template <class T, void (T::* F)()> 561class EventWrapper : public Event |
562{
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574 return l.when() == r.when() && l.priority() == r.priority();
575}
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563 private: 564 T *object; |
565
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577inline bool
578operator!=(const Event &l, const Event &r)
579{
580 return l.when() != r.when() || l.priority() != r.priority();
581}
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566 public: 567 EventWrapper(T *obj, bool del = false, Priority p = Default_Pri) 568 : Event(p), object(obj) 569 { 570 if (del) 571 setFlags(AutoDelete); 572 } 573 574 void process() { (object->*F)(); } 575 576 const std::string 577 name() const 578 { 579 return object->name() + ".wrapped_event"; 580 } 581 582 const char *description() const { return "EventWrapped"; } 583}; |
584#endif 585 586#endif // __SIM_EVENTQ_HH__
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