packet.hh revision 10975:eba4e93665fc
1/* 2 * Copyright (c) 2012-2015 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 * Copyright (c) 2006 The Regents of The University of Michigan 15 * Copyright (c) 2010,2015 Advanced Micro Devices, Inc. 16 * All rights reserved. 17 * 18 * Redistribution and use in source and binary forms, with or without 19 * modification, are permitted provided that the following conditions are 20 * met: redistributions of source code must retain the above copyright 21 * notice, this list of conditions and the following disclaimer; 22 * redistributions in binary form must reproduce the above copyright 23 * notice, this list of conditions and the following disclaimer in the 24 * documentation and/or other materials provided with the distribution; 25 * neither the name of the copyright holders nor the names of its 26 * contributors may be used to endorse or promote products derived from 27 * this software without specific prior written permission. 28 * 29 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 30 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 31 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 32 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 33 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 34 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 35 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 36 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 37 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 38 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 39 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 40 * 41 * Authors: Ron Dreslinski 42 * Steve Reinhardt 43 * Ali Saidi 44 * Andreas Hansson 45 */ 46 47/** 48 * @file 49 * Declaration of the Packet class. 50 */ 51 52#ifndef __MEM_PACKET_HH__ 53#define __MEM_PACKET_HH__ 54 55#include <bitset> 56#include <cassert> 57#include <list> 58 59#include "base/cast.hh" 60#include "base/compiler.hh" 61#include "base/flags.hh" 62#include "base/misc.hh" 63#include "base/printable.hh" 64#include "base/types.hh" 65#include "mem/request.hh" 66#include "sim/core.hh" 67 68class Packet; 69typedef Packet *PacketPtr; 70typedef uint8_t* PacketDataPtr; 71typedef std::list<PacketPtr> PacketList; 72 73class MemCmd 74{ 75 friend class Packet; 76 77 public: 78 /** 79 * List of all commands associated with a packet. 80 */ 81 enum Command 82 { 83 InvalidCmd, 84 ReadReq, 85 ReadResp, 86 ReadRespWithInvalidate, 87 WriteReq, 88 WriteResp, 89 Writeback, 90 CleanEvict, 91 SoftPFReq, 92 HardPFReq, 93 SoftPFResp, 94 HardPFResp, 95 WriteLineReq, 96 UpgradeReq, 97 SCUpgradeReq, // Special "weak" upgrade for StoreCond 98 UpgradeResp, 99 SCUpgradeFailReq, // Failed SCUpgradeReq in MSHR (never sent) 100 UpgradeFailResp, // Valid for SCUpgradeReq only 101 ReadExReq, 102 ReadExResp, 103 ReadCleanReq, 104 ReadSharedReq, 105 LoadLockedReq, 106 StoreCondReq, 107 StoreCondFailReq, // Failed StoreCondReq in MSHR (never sent) 108 StoreCondResp, 109 SwapReq, 110 SwapResp, 111 MessageReq, 112 MessageResp, 113 ReleaseReq, 114 ReleaseResp, 115 AcquireReq, 116 AcquireResp, 117 // Error responses 118 // @TODO these should be classified as responses rather than 119 // requests; coding them as requests initially for backwards 120 // compatibility 121 InvalidDestError, // packet dest field invalid 122 BadAddressError, // memory address invalid 123 FunctionalReadError, // unable to fulfill functional read 124 FunctionalWriteError, // unable to fulfill functional write 125 // Fake simulator-only commands 126 PrintReq, // Print state matching address 127 FlushReq, //request for a cache flush 128 InvalidateReq, // request for address to be invalidated 129 InvalidateResp, 130 NUM_MEM_CMDS 131 }; 132 133 private: 134 /** 135 * List of command attributes. 136 */ 137 enum Attribute 138 { 139 IsRead, //!< Data flows from responder to requester 140 IsWrite, //!< Data flows from requester to responder 141 IsUpgrade, 142 IsInvalidate, 143 NeedsExclusive, //!< Requires exclusive copy to complete in-cache 144 IsRequest, //!< Issued by requester 145 IsResponse, //!< Issue by responder 146 NeedsResponse, //!< Requester needs response from target 147 IsSWPrefetch, 148 IsHWPrefetch, 149 IsLlsc, //!< Alpha/MIPS LL or SC access 150 HasData, //!< There is an associated payload 151 IsError, //!< Error response 152 IsPrint, //!< Print state matching address (for debugging) 153 IsFlush, //!< Flush the address from caches 154 IsAcquire, //!< Acquire operation 155 IsRelease, //!< Release operation 156 NUM_COMMAND_ATTRIBUTES 157 }; 158 159 /** 160 * Structure that defines attributes and other data associated 161 * with a Command. 162 */ 163 struct CommandInfo 164 { 165 /// Set of attribute flags. 166 const std::bitset<NUM_COMMAND_ATTRIBUTES> attributes; 167 /// Corresponding response for requests; InvalidCmd if no 168 /// response is applicable. 169 const Command response; 170 /// String representation (for printing) 171 const std::string str; 172 }; 173 174 /// Array to map Command enum to associated info. 175 static const CommandInfo commandInfo[]; 176 177 private: 178 179 Command cmd; 180 181 bool 182 testCmdAttrib(MemCmd::Attribute attrib) const 183 { 184 return commandInfo[cmd].attributes[attrib] != 0; 185 } 186 187 public: 188 189 bool isRead() const { return testCmdAttrib(IsRead); } 190 bool isWrite() const { return testCmdAttrib(IsWrite); } 191 bool isUpgrade() const { return testCmdAttrib(IsUpgrade); } 192 bool isRequest() const { return testCmdAttrib(IsRequest); } 193 bool isResponse() const { return testCmdAttrib(IsResponse); } 194 bool needsExclusive() const { return testCmdAttrib(NeedsExclusive); } 195 bool needsResponse() const { return testCmdAttrib(NeedsResponse); } 196 bool isInvalidate() const { return testCmdAttrib(IsInvalidate); } 197 198 /** 199 * Check if this particular packet type carries payload data. Note 200 * that this does not reflect if the data pointer of the packet is 201 * valid or not. 202 */ 203 bool hasData() const { return testCmdAttrib(HasData); } 204 bool isLLSC() const { return testCmdAttrib(IsLlsc); } 205 bool isSWPrefetch() const { return testCmdAttrib(IsSWPrefetch); } 206 bool isHWPrefetch() const { return testCmdAttrib(IsHWPrefetch); } 207 bool isPrefetch() const { return testCmdAttrib(IsSWPrefetch) || 208 testCmdAttrib(IsHWPrefetch); } 209 bool isError() const { return testCmdAttrib(IsError); } 210 bool isPrint() const { return testCmdAttrib(IsPrint); } 211 bool isFlush() const { return testCmdAttrib(IsFlush); } 212 bool isAcquire() const { return testCmdAttrib(IsAcquire); } 213 bool isRelease() const { return testCmdAttrib(IsRelease); } 214 215 const Command 216 responseCommand() const 217 { 218 return commandInfo[cmd].response; 219 } 220 221 /// Return the string to a cmd given by idx. 222 const std::string &toString() const { return commandInfo[cmd].str; } 223 int toInt() const { return (int)cmd; } 224 225 MemCmd(Command _cmd) : cmd(_cmd) { } 226 MemCmd(int _cmd) : cmd((Command)_cmd) { } 227 MemCmd() : cmd(InvalidCmd) { } 228 229 bool operator==(MemCmd c2) const { return (cmd == c2.cmd); } 230 bool operator!=(MemCmd c2) const { return (cmd != c2.cmd); } 231}; 232 233/** 234 * A Packet is used to encapsulate a transfer between two objects in 235 * the memory system (e.g., the L1 and L2 cache). (In contrast, a 236 * single Request travels all the way from the requester to the 237 * ultimate destination and back, possibly being conveyed by several 238 * different Packets along the way.) 239 */ 240class Packet : public Printable 241{ 242 public: 243 typedef uint32_t FlagsType; 244 typedef ::Flags<FlagsType> Flags; 245 246 private: 247 248 enum : FlagsType { 249 // Flags to transfer across when copying a packet 250 COPY_FLAGS = 0x0000000F, 251 252 SHARED = 0x00000001, 253 // Special control flags 254 /// Special timing-mode atomic snoop for multi-level coherence. 255 EXPRESS_SNOOP = 0x00000002, 256 /// Does supplier have exclusive copy? 257 /// Useful for multi-level coherence. 258 SUPPLY_EXCLUSIVE = 0x00000004, 259 // Snoop response flags 260 MEM_INHIBIT = 0x00000008, 261 262 /// Are the 'addr' and 'size' fields valid? 263 VALID_ADDR = 0x00000100, 264 VALID_SIZE = 0x00000200, 265 266 /// Is the data pointer set to a value that shouldn't be freed 267 /// when the packet is destroyed? 268 STATIC_DATA = 0x00001000, 269 /// The data pointer points to a value that should be freed when 270 /// the packet is destroyed. The pointer is assumed to be pointing 271 /// to an array, and delete [] is consequently called 272 DYNAMIC_DATA = 0x00002000, 273 274 /// suppress the error if this packet encounters a functional 275 /// access failure. 276 SUPPRESS_FUNC_ERROR = 0x00008000, 277 278 // Signal block present to squash prefetch and cache evict packets 279 // through express snoop flag 280 BLOCK_CACHED = 0x00010000 281 }; 282 283 Flags flags; 284 285 public: 286 typedef MemCmd::Command Command; 287 288 /// The command field of the packet. 289 MemCmd cmd; 290 291 /// A pointer to the original request. 292 const RequestPtr req; 293 294 private: 295 /** 296 * A pointer to the data being transfered. It can be differnt 297 * sizes at each level of the heirarchy so it belongs in the 298 * packet, not request. This may or may not be populated when a 299 * responder recieves the packet. If not populated it memory should 300 * be allocated. 301 */ 302 PacketDataPtr data; 303 304 /// The address of the request. This address could be virtual or 305 /// physical, depending on the system configuration. 306 Addr addr; 307 308 /// True if the request targets the secure memory space. 309 bool _isSecure; 310 311 /// The size of the request or transfer. 312 unsigned size; 313 314 /** 315 * Track the bytes found that satisfy a functional read. 316 */ 317 std::vector<bool> bytesValid; 318 319 public: 320 321 /** 322 * The extra delay from seeing the packet until the header is 323 * transmitted. This delay is used to communicate the crossbar 324 * forwarding latency to the neighbouring object (e.g. a cache) 325 * that actually makes the packet wait. As the delay is relative, 326 * a 32-bit unsigned should be sufficient. 327 */ 328 uint32_t headerDelay; 329 330 /** 331 * The extra pipelining delay from seeing the packet until the end of 332 * payload is transmitted by the component that provided it (if 333 * any). This includes the header delay. Similar to the header 334 * delay, this is used to make up for the fact that the 335 * crossbar does not make the packet wait. As the delay is 336 * relative, a 32-bit unsigned should be sufficient. 337 */ 338 uint32_t payloadDelay; 339 340 /** 341 * A virtual base opaque structure used to hold state associated 342 * with the packet (e.g., an MSHR), specific to a MemObject that 343 * sees the packet. A pointer to this state is returned in the 344 * packet's response so that the MemObject in question can quickly 345 * look up the state needed to process it. A specific subclass 346 * would be derived from this to carry state specific to a 347 * particular sending device. 348 * 349 * As multiple MemObjects may add their SenderState throughout the 350 * memory system, the SenderStates create a stack, where a 351 * MemObject can add a new Senderstate, as long as the 352 * predecessing SenderState is restored when the response comes 353 * back. For this reason, the predecessor should always be 354 * populated with the current SenderState of a packet before 355 * modifying the senderState field in the request packet. 356 */ 357 struct SenderState 358 { 359 SenderState* predecessor; 360 SenderState() : predecessor(NULL) {} 361 virtual ~SenderState() {} 362 }; 363 364 /** 365 * Object used to maintain state of a PrintReq. The senderState 366 * field of a PrintReq should always be of this type. 367 */ 368 class PrintReqState : public SenderState 369 { 370 private: 371 /** 372 * An entry in the label stack. 373 */ 374 struct LabelStackEntry 375 { 376 const std::string label; 377 std::string *prefix; 378 bool labelPrinted; 379 LabelStackEntry(const std::string &_label, std::string *_prefix); 380 }; 381 382 typedef std::list<LabelStackEntry> LabelStack; 383 LabelStack labelStack; 384 385 std::string *curPrefixPtr; 386 387 public: 388 std::ostream &os; 389 const int verbosity; 390 391 PrintReqState(std::ostream &os, int verbosity = 0); 392 ~PrintReqState(); 393 394 /** 395 * Returns the current line prefix. 396 */ 397 const std::string &curPrefix() { return *curPrefixPtr; } 398 399 /** 400 * Push a label onto the label stack, and prepend the given 401 * prefix string onto the current prefix. Labels will only be 402 * printed if an object within the label's scope is printed. 403 */ 404 void pushLabel(const std::string &lbl, 405 const std::string &prefix = " "); 406 407 /** 408 * Pop a label off the label stack. 409 */ 410 void popLabel(); 411 412 /** 413 * Print all of the pending unprinted labels on the 414 * stack. Called by printObj(), so normally not called by 415 * users unless bypassing printObj(). 416 */ 417 void printLabels(); 418 419 /** 420 * Print a Printable object to os, because it matched the 421 * address on a PrintReq. 422 */ 423 void printObj(Printable *obj); 424 }; 425 426 /** 427 * This packet's sender state. Devices should use dynamic_cast<> 428 * to cast to the state appropriate to the sender. The intent of 429 * this variable is to allow a device to attach extra information 430 * to a request. A response packet must return the sender state 431 * that was attached to the original request (even if a new packet 432 * is created). 433 */ 434 SenderState *senderState; 435 436 /** 437 * Push a new sender state to the packet and make the current 438 * sender state the predecessor of the new one. This should be 439 * prefered over direct manipulation of the senderState member 440 * variable. 441 * 442 * @param sender_state SenderState to push at the top of the stack 443 */ 444 void pushSenderState(SenderState *sender_state); 445 446 /** 447 * Pop the top of the state stack and return a pointer to it. This 448 * assumes the current sender state is not NULL. This should be 449 * preferred over direct manipulation of the senderState member 450 * variable. 451 * 452 * @return The current top of the stack 453 */ 454 SenderState *popSenderState(); 455 456 /** 457 * Go through the sender state stack and return the first instance 458 * that is of type T (as determined by a dynamic_cast). If there 459 * is no sender state of type T, NULL is returned. 460 * 461 * @return The topmost state of type T 462 */ 463 template <typename T> 464 T * findNextSenderState() const 465 { 466 T *t = NULL; 467 SenderState* sender_state = senderState; 468 while (t == NULL && sender_state != NULL) { 469 t = dynamic_cast<T*>(sender_state); 470 sender_state = sender_state->predecessor; 471 } 472 return t; 473 } 474 475 /// Return the string name of the cmd field (for debugging and 476 /// tracing). 477 const std::string &cmdString() const { return cmd.toString(); } 478 479 /// Return the index of this command. 480 inline int cmdToIndex() const { return cmd.toInt(); } 481 482 bool isRead() const { return cmd.isRead(); } 483 bool isWrite() const { return cmd.isWrite(); } 484 bool isUpgrade() const { return cmd.isUpgrade(); } 485 bool isRequest() const { return cmd.isRequest(); } 486 bool isResponse() const { return cmd.isResponse(); } 487 bool needsExclusive() const { return cmd.needsExclusive(); } 488 bool needsResponse() const { return cmd.needsResponse(); } 489 bool isInvalidate() const { return cmd.isInvalidate(); } 490 bool hasData() const { return cmd.hasData(); } 491 bool isLLSC() const { return cmd.isLLSC(); } 492 bool isError() const { return cmd.isError(); } 493 bool isPrint() const { return cmd.isPrint(); } 494 bool isFlush() const { return cmd.isFlush(); } 495 bool isAcquire() const { return cmd.isAcquire(); } 496 bool isRelease() const { return cmd.isRelease(); } 497 498 // Snoop flags 499 void assertMemInhibit() 500 { 501 assert(isRequest()); 502 assert(!flags.isSet(MEM_INHIBIT)); 503 flags.set(MEM_INHIBIT); 504 } 505 bool memInhibitAsserted() const { return flags.isSet(MEM_INHIBIT); } 506 void assertShared() { flags.set(SHARED); } 507 bool sharedAsserted() const { return flags.isSet(SHARED); } 508 509 // Special control flags 510 void setExpressSnoop() { flags.set(EXPRESS_SNOOP); } 511 bool isExpressSnoop() const { return flags.isSet(EXPRESS_SNOOP); } 512 void setSupplyExclusive() { flags.set(SUPPLY_EXCLUSIVE); } 513 bool isSupplyExclusive() const { return flags.isSet(SUPPLY_EXCLUSIVE); } 514 void setSuppressFuncError() { flags.set(SUPPRESS_FUNC_ERROR); } 515 bool suppressFuncError() const { return flags.isSet(SUPPRESS_FUNC_ERROR); } 516 void setBlockCached() { flags.set(BLOCK_CACHED); } 517 bool isBlockCached() const { return flags.isSet(BLOCK_CACHED); } 518 void clearBlockCached() { flags.clear(BLOCK_CACHED); } 519 520 // Network error conditions... encapsulate them as methods since 521 // their encoding keeps changing (from result field to command 522 // field, etc.) 523 void 524 setBadAddress() 525 { 526 assert(isResponse()); 527 cmd = MemCmd::BadAddressError; 528 } 529 530 void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; } 531 532 Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; } 533 /** 534 * Update the address of this packet mid-transaction. This is used 535 * by the address mapper to change an already set address to a new 536 * one based on the system configuration. It is intended to remap 537 * an existing address, so it asserts that the current address is 538 * valid. 539 */ 540 void setAddr(Addr _addr) { assert(flags.isSet(VALID_ADDR)); addr = _addr; } 541 542 unsigned getSize() const { assert(flags.isSet(VALID_SIZE)); return size; } 543 544 Addr getOffset(unsigned int blk_size) const 545 { 546 return getAddr() & Addr(blk_size - 1); 547 } 548 549 Addr getBlockAddr(unsigned int blk_size) const 550 { 551 return getAddr() & ~(Addr(blk_size - 1)); 552 } 553 554 bool isSecure() const 555 { 556 assert(flags.isSet(VALID_ADDR)); 557 return _isSecure; 558 } 559 560 /** 561 * It has been determined that the SC packet should successfully update 562 * memory. Therefore, convert this SC packet to a normal write. 563 */ 564 void 565 convertScToWrite() 566 { 567 assert(isLLSC()); 568 assert(isWrite()); 569 cmd = MemCmd::WriteReq; 570 } 571 572 /** 573 * When ruby is in use, Ruby will monitor the cache line and the 574 * phys memory should treat LL ops as normal reads. 575 */ 576 void 577 convertLlToRead() 578 { 579 assert(isLLSC()); 580 assert(isRead()); 581 cmd = MemCmd::ReadReq; 582 } 583 584 /** 585 * Constructor. Note that a Request object must be constructed 586 * first, but the Requests's physical address and size fields need 587 * not be valid. The command must be supplied. 588 */ 589 Packet(const RequestPtr _req, MemCmd _cmd) 590 : cmd(_cmd), req(_req), data(nullptr), addr(0), _isSecure(false), 591 size(0), headerDelay(0), payloadDelay(0), 592 senderState(NULL) 593 { 594 if (req->hasPaddr()) { 595 addr = req->getPaddr(); 596 flags.set(VALID_ADDR); 597 _isSecure = req->isSecure(); 598 } 599 if (req->hasSize()) { 600 size = req->getSize(); 601 flags.set(VALID_SIZE); 602 } 603 } 604 605 /** 606 * Alternate constructor if you are trying to create a packet with 607 * a request that is for a whole block, not the address from the 608 * req. this allows for overriding the size/addr of the req. 609 */ 610 Packet(const RequestPtr _req, MemCmd _cmd, int _blkSize) 611 : cmd(_cmd), req(_req), data(nullptr), addr(0), _isSecure(false), 612 headerDelay(0), payloadDelay(0), 613 senderState(NULL) 614 { 615 if (req->hasPaddr()) { 616 addr = req->getPaddr() & ~(_blkSize - 1); 617 flags.set(VALID_ADDR); 618 _isSecure = req->isSecure(); 619 } 620 size = _blkSize; 621 flags.set(VALID_SIZE); 622 } 623 624 /** 625 * Alternate constructor for copying a packet. Copy all fields 626 * *except* if the original packet's data was dynamic, don't copy 627 * that, as we can't guarantee that the new packet's lifetime is 628 * less than that of the original packet. In this case the new 629 * packet should allocate its own data. 630 */ 631 Packet(const PacketPtr pkt, bool clear_flags, bool alloc_data) 632 : cmd(pkt->cmd), req(pkt->req), 633 data(nullptr), 634 addr(pkt->addr), _isSecure(pkt->_isSecure), size(pkt->size), 635 bytesValid(pkt->bytesValid), 636 headerDelay(pkt->headerDelay), 637 payloadDelay(pkt->payloadDelay), 638 senderState(pkt->senderState) 639 { 640 if (!clear_flags) 641 flags.set(pkt->flags & COPY_FLAGS); 642 643 flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE)); 644 645 // should we allocate space for data, or not, the express 646 // snoops do not need to carry any data as they only serve to 647 // co-ordinate state changes 648 if (alloc_data) { 649 // even if asked to allocate data, if the original packet 650 // holds static data, then the sender will not be doing 651 // any memcpy on receiving the response, thus we simply 652 // carry the pointer forward 653 if (pkt->flags.isSet(STATIC_DATA)) { 654 data = pkt->data; 655 flags.set(STATIC_DATA); 656 } else { 657 allocate(); 658 } 659 } 660 } 661 662 /** 663 * Generate the appropriate read MemCmd based on the Request flags. 664 */ 665 static MemCmd 666 makeReadCmd(const RequestPtr req) 667 { 668 if (req->isLLSC()) 669 return MemCmd::LoadLockedReq; 670 else if (req->isPrefetch()) 671 return MemCmd::SoftPFReq; 672 else 673 return MemCmd::ReadReq; 674 } 675 676 /** 677 * Generate the appropriate write MemCmd based on the Request flags. 678 */ 679 static MemCmd 680 makeWriteCmd(const RequestPtr req) 681 { 682 if (req->isLLSC()) 683 return MemCmd::StoreCondReq; 684 else if (req->isSwap()) 685 return MemCmd::SwapReq; 686 else 687 return MemCmd::WriteReq; 688 } 689 690 /** 691 * Constructor-like methods that return Packets based on Request objects. 692 * Fine-tune the MemCmd type if it's not a vanilla read or write. 693 */ 694 static PacketPtr 695 createRead(const RequestPtr req) 696 { 697 return new Packet(req, makeReadCmd(req)); 698 } 699 700 static PacketPtr 701 createWrite(const RequestPtr req) 702 { 703 return new Packet(req, makeWriteCmd(req)); 704 } 705 706 /** 707 * clean up packet variables 708 */ 709 ~Packet() 710 { 711 // Delete the request object if this is a request packet which 712 // does not need a response, because the requester will not get 713 // a chance. If the request packet needs a response then the 714 // request will be deleted on receipt of the response 715 // packet. We also make sure to never delete the request for 716 // express snoops, even for cases when responses are not 717 // needed (CleanEvict and Writeback), since the snoop packet 718 // re-uses the same request. 719 if (req && isRequest() && !needsResponse() && 720 !isExpressSnoop()) { 721 delete req; 722 } 723 deleteData(); 724 } 725 726 /** 727 * Take a request packet and modify it in place to be suitable for 728 * returning as a response to that request. 729 */ 730 void 731 makeResponse() 732 { 733 assert(needsResponse()); 734 assert(isRequest()); 735 cmd = cmd.responseCommand(); 736 737 // responses are never express, even if the snoop that 738 // triggered them was 739 flags.clear(EXPRESS_SNOOP); 740 } 741 742 void 743 makeAtomicResponse() 744 { 745 makeResponse(); 746 } 747 748 void 749 makeTimingResponse() 750 { 751 makeResponse(); 752 } 753 754 void 755 setFunctionalResponseStatus(bool success) 756 { 757 if (!success) { 758 if (isWrite()) { 759 cmd = MemCmd::FunctionalWriteError; 760 } else { 761 cmd = MemCmd::FunctionalReadError; 762 } 763 } 764 } 765 766 void 767 setSize(unsigned size) 768 { 769 assert(!flags.isSet(VALID_SIZE)); 770 771 this->size = size; 772 flags.set(VALID_SIZE); 773 } 774 775 776 /** 777 * Set the data pointer to the following value that should not be 778 * freed. Static data allows us to do a single memcpy even if 779 * multiple packets are required to get from source to destination 780 * and back. In essence the pointer is set calling dataStatic on 781 * the original packet, and whenever this packet is copied and 782 * forwarded the same pointer is passed on. When a packet 783 * eventually reaches the destination holding the data, it is 784 * copied once into the location originally set. On the way back 785 * to the source, no copies are necessary. 786 */ 787 template <typename T> 788 void 789 dataStatic(T *p) 790 { 791 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 792 data = (PacketDataPtr)p; 793 flags.set(STATIC_DATA); 794 } 795 796 /** 797 * Set the data pointer to the following value that should not be 798 * freed. This version of the function allows the pointer passed 799 * to us to be const. To avoid issues down the line we cast the 800 * constness away, the alternative would be to keep both a const 801 * and non-const data pointer and cleverly choose between 802 * them. Note that this is only allowed for static data. 803 */ 804 template <typename T> 805 void 806 dataStaticConst(const T *p) 807 { 808 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 809 data = const_cast<PacketDataPtr>(p); 810 flags.set(STATIC_DATA); 811 } 812 813 /** 814 * Set the data pointer to a value that should have delete [] 815 * called on it. Dynamic data is local to this packet, and as the 816 * packet travels from source to destination, forwarded packets 817 * will allocate their own data. When a packet reaches the final 818 * destination it will populate the dynamic data of that specific 819 * packet, and on the way back towards the source, memcpy will be 820 * invoked in every step where a new packet was created e.g. in 821 * the caches. Ultimately when the response reaches the source a 822 * final memcpy is needed to extract the data from the packet 823 * before it is deallocated. 824 */ 825 template <typename T> 826 void 827 dataDynamic(T *p) 828 { 829 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 830 data = (PacketDataPtr)p; 831 flags.set(DYNAMIC_DATA); 832 } 833 834 /** 835 * get a pointer to the data ptr. 836 */ 837 template <typename T> 838 T* 839 getPtr() 840 { 841 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA)); 842 return (T*)data; 843 } 844 845 template <typename T> 846 const T* 847 getConstPtr() const 848 { 849 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA)); 850 return (const T*)data; 851 } 852 853 /** 854 * return the value of what is pointed to in the packet. 855 */ 856 template <typename T> 857 T get() const; 858 859 /** 860 * set the value in the data pointer to v. 861 */ 862 template <typename T> 863 void set(T v); 864 865 /** 866 * Copy data into the packet from the provided pointer. 867 */ 868 void 869 setData(const uint8_t *p) 870 { 871 // we should never be copying data onto itself, which means we 872 // must idenfity packets with static data, as they carry the 873 // same pointer from source to destination and back 874 assert(p != getPtr<uint8_t>() || flags.isSet(STATIC_DATA)); 875 876 if (p != getPtr<uint8_t>()) 877 // for packet with allocated dynamic data, we copy data from 878 // one to the other, e.g. a forwarded response to a response 879 std::memcpy(getPtr<uint8_t>(), p, getSize()); 880 } 881 882 /** 883 * Copy data into the packet from the provided block pointer, 884 * which is aligned to the given block size. 885 */ 886 void 887 setDataFromBlock(const uint8_t *blk_data, int blkSize) 888 { 889 setData(blk_data + getOffset(blkSize)); 890 } 891 892 /** 893 * Copy data from the packet to the provided block pointer, which 894 * is aligned to the given block size. 895 */ 896 void 897 writeData(uint8_t *p) const 898 { 899 std::memcpy(p, getConstPtr<uint8_t>(), getSize()); 900 } 901 902 /** 903 * Copy data from the packet to the memory at the provided pointer. 904 */ 905 void 906 writeDataToBlock(uint8_t *blk_data, int blkSize) const 907 { 908 writeData(blk_data + getOffset(blkSize)); 909 } 910 911 /** 912 * delete the data pointed to in the data pointer. Ok to call to 913 * matter how data was allocted. 914 */ 915 void 916 deleteData() 917 { 918 if (flags.isSet(DYNAMIC_DATA)) 919 delete [] data; 920 921 flags.clear(STATIC_DATA|DYNAMIC_DATA); 922 data = NULL; 923 } 924 925 /** Allocate memory for the packet. */ 926 void 927 allocate() 928 { 929 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 930 flags.set(DYNAMIC_DATA); 931 data = new uint8_t[getSize()]; 932 } 933 934 /** 935 * Check a functional request against a memory value stored in 936 * another packet (i.e. an in-transit request or 937 * response). Returns true if the current packet is a read, and 938 * the other packet provides the data, which is then copied to the 939 * current packet. If the current packet is a write, and the other 940 * packet intersects this one, then we update the data 941 * accordingly. 942 */ 943 bool 944 checkFunctional(PacketPtr other) 945 { 946 // all packets that are carrying a payload should have a valid 947 // data pointer 948 return checkFunctional(other, other->getAddr(), other->isSecure(), 949 other->getSize(), 950 other->hasData() ? 951 other->getPtr<uint8_t>() : NULL); 952 } 953 954 /** 955 * Is this request notification of a clean or dirty eviction from the cache. 956 **/ 957 bool 958 evictingBlock() const 959 { 960 return (cmd == MemCmd::Writeback || 961 cmd == MemCmd::CleanEvict); 962 } 963 964 /** 965 * Does the request need to check for cached copies of the same block 966 * in the memory hierarchy above. 967 **/ 968 bool 969 mustCheckAbove() const 970 { 971 return (cmd == MemCmd::HardPFReq || 972 evictingBlock()); 973 } 974 975 /** 976 * Check a functional request against a memory value represented 977 * by a base/size pair and an associated data array. If the 978 * current packet is a read, it may be satisfied by the memory 979 * value. If the current packet is a write, it may update the 980 * memory value. 981 */ 982 bool 983 checkFunctional(Printable *obj, Addr base, bool is_secure, int size, 984 uint8_t *_data); 985 986 /** 987 * Push label for PrintReq (safe to call unconditionally). 988 */ 989 void 990 pushLabel(const std::string &lbl) 991 { 992 if (isPrint()) 993 safe_cast<PrintReqState*>(senderState)->pushLabel(lbl); 994 } 995 996 /** 997 * Pop label for PrintReq (safe to call unconditionally). 998 */ 999 void 1000 popLabel() 1001 { 1002 if (isPrint()) 1003 safe_cast<PrintReqState*>(senderState)->popLabel(); 1004 } 1005 1006 void print(std::ostream &o, int verbosity = 0, 1007 const std::string &prefix = "") const; 1008 1009 /** 1010 * A no-args wrapper of print(std::ostream...) 1011 * meant to be invoked from DPRINTFs 1012 * avoiding string overheads in fast mode 1013 * @return string with the request's type and start<->end addresses 1014 */ 1015 std::string print() const; 1016}; 1017 1018#endif //__MEM_PACKET_HH 1019