packet.hh revision 10739:4cfe55719da5
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 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 SoftPFReq, 91 HardPFReq, 92 SoftPFResp, 93 HardPFResp, 94 WriteInvalidateReq, 95 WriteInvalidateResp, 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 LoadLockedReq, 104 StoreCondReq, 105 StoreCondFailReq, // Failed StoreCondReq in MSHR (never sent) 106 StoreCondResp, 107 SwapReq, 108 SwapResp, 109 MessageReq, 110 MessageResp, 111 // Error responses 112 // @TODO these should be classified as responses rather than 113 // requests; coding them as requests initially for backwards 114 // compatibility 115 InvalidDestError, // packet dest field invalid 116 BadAddressError, // memory address invalid 117 FunctionalReadError, // unable to fulfill functional read 118 FunctionalWriteError, // unable to fulfill functional write 119 // Fake simulator-only commands 120 PrintReq, // Print state matching address 121 FlushReq, //request for a cache flush 122 InvalidationReq, // request for address to be invalidated from lsq 123 NUM_MEM_CMDS 124 }; 125 126 private: 127 /** 128 * List of command attributes. 129 */ 130 enum Attribute 131 { 132 IsRead, //!< Data flows from responder to requester 133 IsWrite, //!< Data flows from requester to responder 134 IsUpgrade, 135 IsInvalidate, 136 NeedsExclusive, //!< Requires exclusive copy to complete in-cache 137 IsRequest, //!< Issued by requester 138 IsResponse, //!< Issue by responder 139 NeedsResponse, //!< Requester needs response from target 140 IsSWPrefetch, 141 IsHWPrefetch, 142 IsLlsc, //!< Alpha/MIPS LL or SC access 143 HasData, //!< There is an associated payload 144 IsError, //!< Error response 145 IsPrint, //!< Print state matching address (for debugging) 146 IsFlush, //!< Flush the address from caches 147 NUM_COMMAND_ATTRIBUTES 148 }; 149 150 /** 151 * Structure that defines attributes and other data associated 152 * with a Command. 153 */ 154 struct CommandInfo 155 { 156 /// Set of attribute flags. 157 const std::bitset<NUM_COMMAND_ATTRIBUTES> attributes; 158 /// Corresponding response for requests; InvalidCmd if no 159 /// response is applicable. 160 const Command response; 161 /// String representation (for printing) 162 const std::string str; 163 }; 164 165 /// Array to map Command enum to associated info. 166 static const CommandInfo commandInfo[]; 167 168 private: 169 170 Command cmd; 171 172 bool 173 testCmdAttrib(MemCmd::Attribute attrib) const 174 { 175 return commandInfo[cmd].attributes[attrib] != 0; 176 } 177 178 public: 179 180 bool isRead() const { return testCmdAttrib(IsRead); } 181 bool isWrite() const { return testCmdAttrib(IsWrite); } 182 bool isUpgrade() const { return testCmdAttrib(IsUpgrade); } 183 bool isRequest() const { return testCmdAttrib(IsRequest); } 184 bool isResponse() const { return testCmdAttrib(IsResponse); } 185 bool needsExclusive() const { return testCmdAttrib(NeedsExclusive); } 186 bool needsResponse() const { return testCmdAttrib(NeedsResponse); } 187 bool isInvalidate() const { return testCmdAttrib(IsInvalidate); } 188 bool isWriteInvalidate() const { return testCmdAttrib(IsWrite) && 189 testCmdAttrib(IsInvalidate); } 190 191 /** 192 * Check if this particular packet type carries payload data. Note 193 * that this does not reflect if the data pointer of the packet is 194 * valid or not. 195 */ 196 bool hasData() const { return testCmdAttrib(HasData); } 197 bool isLLSC() const { return testCmdAttrib(IsLlsc); } 198 bool isSWPrefetch() const { return testCmdAttrib(IsSWPrefetch); } 199 bool isHWPrefetch() const { return testCmdAttrib(IsHWPrefetch); } 200 bool isPrefetch() const { return testCmdAttrib(IsSWPrefetch) || 201 testCmdAttrib(IsHWPrefetch); } 202 bool isError() const { return testCmdAttrib(IsError); } 203 bool isPrint() const { return testCmdAttrib(IsPrint); } 204 bool isFlush() const { return testCmdAttrib(IsFlush); } 205 206 const Command 207 responseCommand() const 208 { 209 return commandInfo[cmd].response; 210 } 211 212 /// Return the string to a cmd given by idx. 213 const std::string &toString() const { return commandInfo[cmd].str; } 214 int toInt() const { return (int)cmd; } 215 216 MemCmd(Command _cmd) : cmd(_cmd) { } 217 MemCmd(int _cmd) : cmd((Command)_cmd) { } 218 MemCmd() : cmd(InvalidCmd) { } 219 220 bool operator==(MemCmd c2) const { return (cmd == c2.cmd); } 221 bool operator!=(MemCmd c2) const { return (cmd != c2.cmd); } 222}; 223 224/** 225 * A Packet is used to encapsulate a transfer between two objects in 226 * the memory system (e.g., the L1 and L2 cache). (In contrast, a 227 * single Request travels all the way from the requester to the 228 * ultimate destination and back, possibly being conveyed by several 229 * different Packets along the way.) 230 */ 231class Packet : public Printable 232{ 233 public: 234 typedef uint32_t FlagsType; 235 typedef ::Flags<FlagsType> Flags; 236 237 private: 238 static const FlagsType PUBLIC_FLAGS = 0x00000000; 239 static const FlagsType PRIVATE_FLAGS = 0x00007F0F; 240 static const FlagsType COPY_FLAGS = 0x0000000F; 241 242 static const FlagsType SHARED = 0x00000001; 243 // Special control flags 244 /// Special timing-mode atomic snoop for multi-level coherence. 245 static const FlagsType EXPRESS_SNOOP = 0x00000002; 246 /// Does supplier have exclusive copy? 247 /// Useful for multi-level coherence. 248 static const FlagsType SUPPLY_EXCLUSIVE = 0x00000004; 249 // Snoop response flags 250 static const FlagsType MEM_INHIBIT = 0x00000008; 251 /// Are the 'addr' and 'size' fields valid? 252 static const FlagsType VALID_ADDR = 0x00000100; 253 static const FlagsType VALID_SIZE = 0x00000200; 254 /// Is the data pointer set to a value that shouldn't be freed 255 /// when the packet is destroyed? 256 static const FlagsType STATIC_DATA = 0x00001000; 257 /// The data pointer points to a value that should be freed when 258 /// the packet is destroyed. The pointer is assumed to be pointing 259 /// to an array, and delete [] is consequently called 260 static const FlagsType DYNAMIC_DATA = 0x00002000; 261 /// suppress the error if this packet encounters a functional 262 /// access failure. 263 static const FlagsType SUPPRESS_FUNC_ERROR = 0x00008000; 264 // Signal prefetch squash through express snoop flag 265 static const FlagsType PREFETCH_SNOOP_SQUASH = 0x00010000; 266 267 Flags flags; 268 269 public: 270 typedef MemCmd::Command Command; 271 272 /// The command field of the packet. 273 MemCmd cmd; 274 275 /// A pointer to the original request. 276 const RequestPtr req; 277 278 private: 279 /** 280 * A pointer to the data being transfered. It can be differnt 281 * sizes at each level of the heirarchy so it belongs in the 282 * packet, not request. This may or may not be populated when a 283 * responder recieves the packet. If not populated it memory should 284 * be allocated. 285 */ 286 PacketDataPtr data; 287 288 /// The address of the request. This address could be virtual or 289 /// physical, depending on the system configuration. 290 Addr addr; 291 292 /// True if the request targets the secure memory space. 293 bool _isSecure; 294 295 /// The size of the request or transfer. 296 unsigned size; 297 298 /** 299 * The original value of the command field. Only valid when the 300 * current command field is an error condition; in that case, the 301 * previous contents of the command field are copied here. This 302 * field is *not* set on non-error responses. 303 */ 304 MemCmd origCmd; 305 306 /** 307 * Track the bytes found that satisfy a functional read. 308 */ 309 std::vector<bool> bytesValid; 310 311 public: 312 313 /** 314 * The extra delay from seeing the packet until the header is 315 * transmitted. This delay is used to communicate the crossbar 316 * forwarding latency to the neighbouring object (e.g. a cache) 317 * that actually makes the packet wait. As the delay is relative, 318 * a 32-bit unsigned should be sufficient. 319 */ 320 uint32_t headerDelay; 321 322 /** 323 * The extra pipelining delay from seeing the packet until the end of 324 * payload is transmitted by the component that provided it (if 325 * any). This includes the header delay. Similar to the header 326 * delay, this is used to make up for the fact that the 327 * crossbar does not make the packet wait. As the delay is 328 * relative, a 32-bit unsigned should be sufficient. 329 */ 330 uint32_t payloadDelay; 331 332 /** 333 * A virtual base opaque structure used to hold state associated 334 * with the packet (e.g., an MSHR), specific to a MemObject that 335 * sees the packet. A pointer to this state is returned in the 336 * packet's response so that the MemObject in question can quickly 337 * look up the state needed to process it. A specific subclass 338 * would be derived from this to carry state specific to a 339 * particular sending device. 340 * 341 * As multiple MemObjects may add their SenderState throughout the 342 * memory system, the SenderStates create a stack, where a 343 * MemObject can add a new Senderstate, as long as the 344 * predecessing SenderState is restored when the response comes 345 * back. For this reason, the predecessor should always be 346 * populated with the current SenderState of a packet before 347 * modifying the senderState field in the request packet. 348 */ 349 struct SenderState 350 { 351 SenderState* predecessor; 352 SenderState() : predecessor(NULL) {} 353 virtual ~SenderState() {} 354 }; 355 356 /** 357 * Object used to maintain state of a PrintReq. The senderState 358 * field of a PrintReq should always be of this type. 359 */ 360 class PrintReqState : public SenderState 361 { 362 private: 363 /** 364 * An entry in the label stack. 365 */ 366 struct LabelStackEntry 367 { 368 const std::string label; 369 std::string *prefix; 370 bool labelPrinted; 371 LabelStackEntry(const std::string &_label, std::string *_prefix); 372 }; 373 374 typedef std::list<LabelStackEntry> LabelStack; 375 LabelStack labelStack; 376 377 std::string *curPrefixPtr; 378 379 public: 380 std::ostream &os; 381 const int verbosity; 382 383 PrintReqState(std::ostream &os, int verbosity = 0); 384 ~PrintReqState(); 385 386 /** 387 * Returns the current line prefix. 388 */ 389 const std::string &curPrefix() { return *curPrefixPtr; } 390 391 /** 392 * Push a label onto the label stack, and prepend the given 393 * prefix string onto the current prefix. Labels will only be 394 * printed if an object within the label's scope is printed. 395 */ 396 void pushLabel(const std::string &lbl, 397 const std::string &prefix = " "); 398 399 /** 400 * Pop a label off the label stack. 401 */ 402 void popLabel(); 403 404 /** 405 * Print all of the pending unprinted labels on the 406 * stack. Called by printObj(), so normally not called by 407 * users unless bypassing printObj(). 408 */ 409 void printLabels(); 410 411 /** 412 * Print a Printable object to os, because it matched the 413 * address on a PrintReq. 414 */ 415 void printObj(Printable *obj); 416 }; 417 418 /** 419 * This packet's sender state. Devices should use dynamic_cast<> 420 * to cast to the state appropriate to the sender. The intent of 421 * this variable is to allow a device to attach extra information 422 * to a request. A response packet must return the sender state 423 * that was attached to the original request (even if a new packet 424 * is created). 425 */ 426 SenderState *senderState; 427 428 /** 429 * Push a new sender state to the packet and make the current 430 * sender state the predecessor of the new one. This should be 431 * prefered over direct manipulation of the senderState member 432 * variable. 433 * 434 * @param sender_state SenderState to push at the top of the stack 435 */ 436 void pushSenderState(SenderState *sender_state); 437 438 /** 439 * Pop the top of the state stack and return a pointer to it. This 440 * assumes the current sender state is not NULL. This should be 441 * preferred over direct manipulation of the senderState member 442 * variable. 443 * 444 * @return The current top of the stack 445 */ 446 SenderState *popSenderState(); 447 448 /** 449 * Go through the sender state stack and return the first instance 450 * that is of type T (as determined by a dynamic_cast). If there 451 * is no sender state of type T, NULL is returned. 452 * 453 * @return The topmost state of type T 454 */ 455 template <typename T> 456 T * findNextSenderState() const 457 { 458 T *t = NULL; 459 SenderState* sender_state = senderState; 460 while (t == NULL && sender_state != NULL) { 461 t = dynamic_cast<T*>(sender_state); 462 sender_state = sender_state->predecessor; 463 } 464 return t; 465 } 466 467 /// Return the string name of the cmd field (for debugging and 468 /// tracing). 469 const std::string &cmdString() const { return cmd.toString(); } 470 471 /// Return the index of this command. 472 inline int cmdToIndex() const { return cmd.toInt(); } 473 474 bool isRead() const { return cmd.isRead(); } 475 bool isWrite() const { return cmd.isWrite(); } 476 bool isUpgrade() const { return cmd.isUpgrade(); } 477 bool isRequest() const { return cmd.isRequest(); } 478 bool isResponse() const { return cmd.isResponse(); } 479 bool needsExclusive() const { return cmd.needsExclusive(); } 480 bool needsResponse() const { return cmd.needsResponse(); } 481 bool isInvalidate() const { return cmd.isInvalidate(); } 482 bool isWriteInvalidate() const { return cmd.isWriteInvalidate(); } 483 bool hasData() const { return cmd.hasData(); } 484 bool isLLSC() const { return cmd.isLLSC(); } 485 bool isError() const { return cmd.isError(); } 486 bool isPrint() const { return cmd.isPrint(); } 487 bool isFlush() const { return cmd.isFlush(); } 488 489 // Snoop flags 490 void assertMemInhibit() 491 { 492 assert(isRequest()); 493 assert(!flags.isSet(MEM_INHIBIT)); 494 flags.set(MEM_INHIBIT); 495 } 496 bool memInhibitAsserted() const { return flags.isSet(MEM_INHIBIT); } 497 void assertShared() { flags.set(SHARED); } 498 bool sharedAsserted() const { return flags.isSet(SHARED); } 499 500 // Special control flags 501 void setExpressSnoop() { flags.set(EXPRESS_SNOOP); } 502 bool isExpressSnoop() const { return flags.isSet(EXPRESS_SNOOP); } 503 void setSupplyExclusive() { flags.set(SUPPLY_EXCLUSIVE); } 504 void clearSupplyExclusive() { flags.clear(SUPPLY_EXCLUSIVE); } 505 bool isSupplyExclusive() const { return flags.isSet(SUPPLY_EXCLUSIVE); } 506 void setSuppressFuncError() { flags.set(SUPPRESS_FUNC_ERROR); } 507 bool suppressFuncError() const { return flags.isSet(SUPPRESS_FUNC_ERROR); } 508 void setPrefetchSquashed() { flags.set(PREFETCH_SNOOP_SQUASH); } 509 bool prefetchSquashed() const { return flags.isSet(PREFETCH_SNOOP_SQUASH); } 510 511 // Network error conditions... encapsulate them as methods since 512 // their encoding keeps changing (from result field to command 513 // field, etc.) 514 void 515 setBadAddress() 516 { 517 assert(isResponse()); 518 cmd = MemCmd::BadAddressError; 519 } 520 521 bool hadBadAddress() const { return cmd == MemCmd::BadAddressError; } 522 void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; } 523 524 Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; } 525 /** 526 * Update the address of this packet mid-transaction. This is used 527 * by the address mapper to change an already set address to a new 528 * one based on the system configuration. It is intended to remap 529 * an existing address, so it asserts that the current address is 530 * valid. 531 */ 532 void setAddr(Addr _addr) { assert(flags.isSet(VALID_ADDR)); addr = _addr; } 533 534 unsigned getSize() const { assert(flags.isSet(VALID_SIZE)); return size; } 535 Addr getOffset(int blkSize) const { return getAddr() & (Addr)(blkSize - 1); } 536 537 bool isSecure() const 538 { 539 assert(flags.isSet(VALID_ADDR)); 540 return _isSecure; 541 } 542 543 /** 544 * It has been determined that the SC packet should successfully update 545 * memory. Therefore, convert this SC packet to a normal write. 546 */ 547 void 548 convertScToWrite() 549 { 550 assert(isLLSC()); 551 assert(isWrite()); 552 cmd = MemCmd::WriteReq; 553 } 554 555 /** 556 * When ruby is in use, Ruby will monitor the cache line and thus M5 557 * phys memory should treat LL ops as normal reads. 558 */ 559 void 560 convertLlToRead() 561 { 562 assert(isLLSC()); 563 assert(isRead()); 564 cmd = MemCmd::ReadReq; 565 } 566 567 /** 568 * Constructor. Note that a Request object must be constructed 569 * first, but the Requests's physical address and size fields need 570 * not be valid. The command must be supplied. 571 */ 572 Packet(const RequestPtr _req, MemCmd _cmd) 573 : cmd(_cmd), req(_req), data(nullptr), addr(0), _isSecure(false), 574 size(0), headerDelay(0), payloadDelay(0), 575 senderState(NULL) 576 { 577 if (req->hasPaddr()) { 578 addr = req->getPaddr(); 579 flags.set(VALID_ADDR); 580 _isSecure = req->isSecure(); 581 } 582 if (req->hasSize()) { 583 size = req->getSize(); 584 flags.set(VALID_SIZE); 585 } 586 } 587 588 /** 589 * Alternate constructor if you are trying to create a packet with 590 * a request that is for a whole block, not the address from the 591 * req. this allows for overriding the size/addr of the req. 592 */ 593 Packet(const RequestPtr _req, MemCmd _cmd, int _blkSize) 594 : cmd(_cmd), req(_req), data(nullptr), addr(0), _isSecure(false), 595 headerDelay(0), payloadDelay(0), 596 senderState(NULL) 597 { 598 if (req->hasPaddr()) { 599 addr = req->getPaddr() & ~(_blkSize - 1); 600 flags.set(VALID_ADDR); 601 _isSecure = req->isSecure(); 602 } 603 size = _blkSize; 604 flags.set(VALID_SIZE); 605 } 606 607 /** 608 * Alternate constructor for copying a packet. Copy all fields 609 * *except* if the original packet's data was dynamic, don't copy 610 * that, as we can't guarantee that the new packet's lifetime is 611 * less than that of the original packet. In this case the new 612 * packet should allocate its own data. 613 */ 614 Packet(PacketPtr pkt, bool clear_flags, bool alloc_data) 615 : cmd(pkt->cmd), req(pkt->req), 616 data(nullptr), 617 addr(pkt->addr), _isSecure(pkt->_isSecure), size(pkt->size), 618 bytesValid(pkt->bytesValid), 619 headerDelay(pkt->headerDelay), 620 payloadDelay(pkt->payloadDelay), 621 senderState(pkt->senderState) 622 { 623 if (!clear_flags) 624 flags.set(pkt->flags & COPY_FLAGS); 625 626 flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE)); 627 628 // should we allocate space for data, or not, the express 629 // snoops do not need to carry any data as they only serve to 630 // co-ordinate state changes 631 if (alloc_data) { 632 // even if asked to allocate data, if the original packet 633 // holds static data, then the sender will not be doing 634 // any memcpy on receiving the response, thus we simply 635 // carry the pointer forward 636 if (pkt->flags.isSet(STATIC_DATA)) { 637 data = pkt->data; 638 flags.set(STATIC_DATA); 639 } else { 640 allocate(); 641 } 642 } 643 } 644 645 /** 646 * Generate the appropriate read MemCmd based on the Request flags. 647 */ 648 static MemCmd 649 makeReadCmd(const RequestPtr req) 650 { 651 if (req->isLLSC()) 652 return MemCmd::LoadLockedReq; 653 else if (req->isPrefetch()) 654 return MemCmd::SoftPFReq; 655 else 656 return MemCmd::ReadReq; 657 } 658 659 /** 660 * Generate the appropriate write MemCmd based on the Request flags. 661 */ 662 static MemCmd 663 makeWriteCmd(const RequestPtr req) 664 { 665 if (req->isLLSC()) 666 return MemCmd::StoreCondReq; 667 else if (req->isSwap()) 668 return MemCmd::SwapReq; 669 else 670 return MemCmd::WriteReq; 671 } 672 673 /** 674 * Constructor-like methods that return Packets based on Request objects. 675 * Fine-tune the MemCmd type if it's not a vanilla read or write. 676 */ 677 static PacketPtr 678 createRead(const RequestPtr req) 679 { 680 return new Packet(req, makeReadCmd(req)); 681 } 682 683 static PacketPtr 684 createWrite(const RequestPtr req) 685 { 686 return new Packet(req, makeWriteCmd(req)); 687 } 688 689 /** 690 * clean up packet variables 691 */ 692 ~Packet() 693 { 694 // If this is a request packet for which there's no response, 695 // delete the request object here, since the requester will 696 // never get the chance. 697 if (req && isRequest() && !needsResponse()) 698 delete req; 699 deleteData(); 700 } 701 702 /** 703 * Take a request packet and modify it in place to be suitable for 704 * returning as a response to that request. 705 */ 706 void 707 makeResponse() 708 { 709 assert(needsResponse()); 710 assert(isRequest()); 711 origCmd = cmd; 712 cmd = cmd.responseCommand(); 713 714 // responses are never express, even if the snoop that 715 // triggered them was 716 flags.clear(EXPRESS_SNOOP); 717 } 718 719 void 720 makeAtomicResponse() 721 { 722 makeResponse(); 723 } 724 725 void 726 makeTimingResponse() 727 { 728 makeResponse(); 729 } 730 731 void 732 setFunctionalResponseStatus(bool success) 733 { 734 if (!success) { 735 if (isWrite()) { 736 cmd = MemCmd::FunctionalWriteError; 737 } else { 738 cmd = MemCmd::FunctionalReadError; 739 } 740 } 741 } 742 743 void 744 setSize(unsigned size) 745 { 746 assert(!flags.isSet(VALID_SIZE)); 747 748 this->size = size; 749 flags.set(VALID_SIZE); 750 } 751 752 753 /** 754 * Set the data pointer to the following value that should not be 755 * freed. Static data allows us to do a single memcpy even if 756 * multiple packets are required to get from source to destination 757 * and back. In essence the pointer is set calling dataStatic on 758 * the original packet, and whenever this packet is copied and 759 * forwarded the same pointer is passed on. When a packet 760 * eventually reaches the destination holding the data, it is 761 * copied once into the location originally set. On the way back 762 * to the source, no copies are necessary. 763 */ 764 template <typename T> 765 void 766 dataStatic(T *p) 767 { 768 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 769 data = (PacketDataPtr)p; 770 flags.set(STATIC_DATA); 771 } 772 773 /** 774 * Set the data pointer to the following value that should not be 775 * freed. This version of the function allows the pointer passed 776 * to us to be const. To avoid issues down the line we cast the 777 * constness away, the alternative would be to keep both a const 778 * and non-const data pointer and cleverly choose between 779 * them. Note that this is only allowed for static data. 780 */ 781 template <typename T> 782 void 783 dataStaticConst(const T *p) 784 { 785 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 786 data = const_cast<PacketDataPtr>(p); 787 flags.set(STATIC_DATA); 788 } 789 790 /** 791 * Set the data pointer to a value that should have delete [] 792 * called on it. Dynamic data is local to this packet, and as the 793 * packet travels from source to destination, forwarded packets 794 * will allocate their own data. When a packet reaches the final 795 * destination it will populate the dynamic data of that specific 796 * packet, and on the way back towards the source, memcpy will be 797 * invoked in every step where a new packet was created e.g. in 798 * the caches. Ultimately when the response reaches the source a 799 * final memcpy is needed to extract the data from the packet 800 * before it is deallocated. 801 */ 802 template <typename T> 803 void 804 dataDynamic(T *p) 805 { 806 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 807 data = (PacketDataPtr)p; 808 flags.set(DYNAMIC_DATA); 809 } 810 811 /** 812 * get a pointer to the data ptr. 813 */ 814 template <typename T> 815 T* 816 getPtr() 817 { 818 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA)); 819 return (T*)data; 820 } 821 822 template <typename T> 823 const T* 824 getConstPtr() const 825 { 826 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA)); 827 return (const T*)data; 828 } 829 830 /** 831 * return the value of what is pointed to in the packet. 832 */ 833 template <typename T> 834 T get() const; 835 836 /** 837 * set the value in the data pointer to v. 838 */ 839 template <typename T> 840 void set(T v); 841 842 /** 843 * Copy data into the packet from the provided pointer. 844 */ 845 void 846 setData(const uint8_t *p) 847 { 848 // we should never be copying data onto itself, which means we 849 // must idenfity packets with static data, as they carry the 850 // same pointer from source to destination and back 851 assert(p != getPtr<uint8_t>() || flags.isSet(STATIC_DATA)); 852 853 if (p != getPtr<uint8_t>()) 854 // for packet with allocated dynamic data, we copy data from 855 // one to the other, e.g. a forwarded response to a response 856 std::memcpy(getPtr<uint8_t>(), p, getSize()); 857 } 858 859 /** 860 * Copy data into the packet from the provided block pointer, 861 * which is aligned to the given block size. 862 */ 863 void 864 setDataFromBlock(const uint8_t *blk_data, int blkSize) 865 { 866 setData(blk_data + getOffset(blkSize)); 867 } 868 869 /** 870 * Copy data from the packet to the provided block pointer, which 871 * is aligned to the given block size. 872 */ 873 void 874 writeData(uint8_t *p) const 875 { 876 std::memcpy(p, getConstPtr<uint8_t>(), getSize()); 877 } 878 879 /** 880 * Copy data from the packet to the memory at the provided pointer. 881 */ 882 void 883 writeDataToBlock(uint8_t *blk_data, int blkSize) const 884 { 885 writeData(blk_data + getOffset(blkSize)); 886 } 887 888 /** 889 * delete the data pointed to in the data pointer. Ok to call to 890 * matter how data was allocted. 891 */ 892 void 893 deleteData() 894 { 895 if (flags.isSet(DYNAMIC_DATA)) 896 delete [] data; 897 898 flags.clear(STATIC_DATA|DYNAMIC_DATA); 899 data = NULL; 900 } 901 902 /** Allocate memory for the packet. */ 903 void 904 allocate() 905 { 906 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 907 flags.set(DYNAMIC_DATA); 908 data = new uint8_t[getSize()]; 909 } 910 911 /** 912 * Check a functional request against a memory value stored in 913 * another packet (i.e. an in-transit request or 914 * response). Returns true if the current packet is a read, and 915 * the other packet provides the data, which is then copied to the 916 * current packet. If the current packet is a write, and the other 917 * packet intersects this one, then we update the data 918 * accordingly. 919 */ 920 bool 921 checkFunctional(PacketPtr other) 922 { 923 // all packets that are carrying a payload should have a valid 924 // data pointer 925 return checkFunctional(other, other->getAddr(), other->isSecure(), 926 other->getSize(), 927 other->hasData() ? 928 other->getPtr<uint8_t>() : NULL); 929 } 930 931 /** 932 * Check a functional request against a memory value represented 933 * by a base/size pair and an associated data array. If the 934 * current packet is a read, it may be satisfied by the memory 935 * value. If the current packet is a write, it may update the 936 * memory value. 937 */ 938 bool 939 checkFunctional(Printable *obj, Addr base, bool is_secure, int size, 940 uint8_t *_data); 941 942 /** 943 * Push label for PrintReq (safe to call unconditionally). 944 */ 945 void 946 pushLabel(const std::string &lbl) 947 { 948 if (isPrint()) 949 safe_cast<PrintReqState*>(senderState)->pushLabel(lbl); 950 } 951 952 /** 953 * Pop label for PrintReq (safe to call unconditionally). 954 */ 955 void 956 popLabel() 957 { 958 if (isPrint()) 959 safe_cast<PrintReqState*>(senderState)->popLabel(); 960 } 961 962 void print(std::ostream &o, int verbosity = 0, 963 const std::string &prefix = "") const; 964 965 /** 966 * A no-args wrapper of print(std::ostream...) 967 * meant to be invoked from DPRINTFs 968 * avoiding string overheads in fast mode 969 * @return string with the request's type and start<->end addresses 970 */ 971 std::string print() const; 972}; 973 974#endif //__MEM_PACKET_HH 975