packet.hh revision 10763:d524dc4f16ae
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 block present to squash prefetch and cache evict packets 265 // through express snoop flag 266 static const FlagsType BLOCK_CACHED = 0x00010000; 267 268 Flags flags; 269 270 public: 271 typedef MemCmd::Command Command; 272 273 /// The command field of the packet. 274 MemCmd cmd; 275 276 /// A pointer to the original request. 277 const RequestPtr req; 278 279 private: 280 /** 281 * A pointer to the data being transfered. It can be differnt 282 * sizes at each level of the heirarchy so it belongs in the 283 * packet, not request. This may or may not be populated when a 284 * responder recieves the packet. If not populated it memory should 285 * be allocated. 286 */ 287 PacketDataPtr data; 288 289 /// The address of the request. This address could be virtual or 290 /// physical, depending on the system configuration. 291 Addr addr; 292 293 /// True if the request targets the secure memory space. 294 bool _isSecure; 295 296 /// The size of the request or transfer. 297 unsigned size; 298 299 /** 300 * The original value of the command field. Only valid when the 301 * current command field is an error condition; in that case, the 302 * previous contents of the command field are copied here. This 303 * field is *not* set on non-error responses. 304 */ 305 MemCmd origCmd; 306 307 /** 308 * Track the bytes found that satisfy a functional read. 309 */ 310 std::vector<bool> bytesValid; 311 312 public: 313 314 /** 315 * The extra delay from seeing the packet until the header is 316 * transmitted. This delay is used to communicate the crossbar 317 * forwarding latency to the neighbouring object (e.g. a cache) 318 * that actually makes the packet wait. As the delay is relative, 319 * a 32-bit unsigned should be sufficient. 320 */ 321 uint32_t headerDelay; 322 323 /** 324 * The extra pipelining delay from seeing the packet until the end of 325 * payload is transmitted by the component that provided it (if 326 * any). This includes the header delay. Similar to the header 327 * delay, this is used to make up for the fact that the 328 * crossbar does not make the packet wait. As the delay is 329 * relative, a 32-bit unsigned should be sufficient. 330 */ 331 uint32_t payloadDelay; 332 333 /** 334 * A virtual base opaque structure used to hold state associated 335 * with the packet (e.g., an MSHR), specific to a MemObject that 336 * sees the packet. A pointer to this state is returned in the 337 * packet's response so that the MemObject in question can quickly 338 * look up the state needed to process it. A specific subclass 339 * would be derived from this to carry state specific to a 340 * particular sending device. 341 * 342 * As multiple MemObjects may add their SenderState throughout the 343 * memory system, the SenderStates create a stack, where a 344 * MemObject can add a new Senderstate, as long as the 345 * predecessing SenderState is restored when the response comes 346 * back. For this reason, the predecessor should always be 347 * populated with the current SenderState of a packet before 348 * modifying the senderState field in the request packet. 349 */ 350 struct SenderState 351 { 352 SenderState* predecessor; 353 SenderState() : predecessor(NULL) {} 354 virtual ~SenderState() {} 355 }; 356 357 /** 358 * Object used to maintain state of a PrintReq. The senderState 359 * field of a PrintReq should always be of this type. 360 */ 361 class PrintReqState : public SenderState 362 { 363 private: 364 /** 365 * An entry in the label stack. 366 */ 367 struct LabelStackEntry 368 { 369 const std::string label; 370 std::string *prefix; 371 bool labelPrinted; 372 LabelStackEntry(const std::string &_label, std::string *_prefix); 373 }; 374 375 typedef std::list<LabelStackEntry> LabelStack; 376 LabelStack labelStack; 377 378 std::string *curPrefixPtr; 379 380 public: 381 std::ostream &os; 382 const int verbosity; 383 384 PrintReqState(std::ostream &os, int verbosity = 0); 385 ~PrintReqState(); 386 387 /** 388 * Returns the current line prefix. 389 */ 390 const std::string &curPrefix() { return *curPrefixPtr; } 391 392 /** 393 * Push a label onto the label stack, and prepend the given 394 * prefix string onto the current prefix. Labels will only be 395 * printed if an object within the label's scope is printed. 396 */ 397 void pushLabel(const std::string &lbl, 398 const std::string &prefix = " "); 399 400 /** 401 * Pop a label off the label stack. 402 */ 403 void popLabel(); 404 405 /** 406 * Print all of the pending unprinted labels on the 407 * stack. Called by printObj(), so normally not called by 408 * users unless bypassing printObj(). 409 */ 410 void printLabels(); 411 412 /** 413 * Print a Printable object to os, because it matched the 414 * address on a PrintReq. 415 */ 416 void printObj(Printable *obj); 417 }; 418 419 /** 420 * This packet's sender state. Devices should use dynamic_cast<> 421 * to cast to the state appropriate to the sender. The intent of 422 * this variable is to allow a device to attach extra information 423 * to a request. A response packet must return the sender state 424 * that was attached to the original request (even if a new packet 425 * is created). 426 */ 427 SenderState *senderState; 428 429 /** 430 * Push a new sender state to the packet and make the current 431 * sender state the predecessor of the new one. This should be 432 * prefered over direct manipulation of the senderState member 433 * variable. 434 * 435 * @param sender_state SenderState to push at the top of the stack 436 */ 437 void pushSenderState(SenderState *sender_state); 438 439 /** 440 * Pop the top of the state stack and return a pointer to it. This 441 * assumes the current sender state is not NULL. This should be 442 * preferred over direct manipulation of the senderState member 443 * variable. 444 * 445 * @return The current top of the stack 446 */ 447 SenderState *popSenderState(); 448 449 /** 450 * Go through the sender state stack and return the first instance 451 * that is of type T (as determined by a dynamic_cast). If there 452 * is no sender state of type T, NULL is returned. 453 * 454 * @return The topmost state of type T 455 */ 456 template <typename T> 457 T * findNextSenderState() const 458 { 459 T *t = NULL; 460 SenderState* sender_state = senderState; 461 while (t == NULL && sender_state != NULL) { 462 t = dynamic_cast<T*>(sender_state); 463 sender_state = sender_state->predecessor; 464 } 465 return t; 466 } 467 468 /// Return the string name of the cmd field (for debugging and 469 /// tracing). 470 const std::string &cmdString() const { return cmd.toString(); } 471 472 /// Return the index of this command. 473 inline int cmdToIndex() const { return cmd.toInt(); } 474 475 bool isRead() const { return cmd.isRead(); } 476 bool isWrite() const { return cmd.isWrite(); } 477 bool isUpgrade() const { return cmd.isUpgrade(); } 478 bool isRequest() const { return cmd.isRequest(); } 479 bool isResponse() const { return cmd.isResponse(); } 480 bool needsExclusive() const { return cmd.needsExclusive(); } 481 bool needsResponse() const { return cmd.needsResponse(); } 482 bool isInvalidate() const { return cmd.isInvalidate(); } 483 bool isWriteInvalidate() const { return cmd.isWriteInvalidate(); } 484 bool hasData() const { return cmd.hasData(); } 485 bool isLLSC() const { return cmd.isLLSC(); } 486 bool isError() const { return cmd.isError(); } 487 bool isPrint() const { return cmd.isPrint(); } 488 bool isFlush() const { return cmd.isFlush(); } 489 490 // Snoop flags 491 void assertMemInhibit() 492 { 493 assert(isRequest()); 494 assert(!flags.isSet(MEM_INHIBIT)); 495 flags.set(MEM_INHIBIT); 496 } 497 bool memInhibitAsserted() const { return flags.isSet(MEM_INHIBIT); } 498 void assertShared() { flags.set(SHARED); } 499 bool sharedAsserted() const { return flags.isSet(SHARED); } 500 501 // Special control flags 502 void setExpressSnoop() { flags.set(EXPRESS_SNOOP); } 503 bool isExpressSnoop() const { return flags.isSet(EXPRESS_SNOOP); } 504 void setSupplyExclusive() { flags.set(SUPPLY_EXCLUSIVE); } 505 void clearSupplyExclusive() { flags.clear(SUPPLY_EXCLUSIVE); } 506 bool isSupplyExclusive() const { return flags.isSet(SUPPLY_EXCLUSIVE); } 507 void setSuppressFuncError() { flags.set(SUPPRESS_FUNC_ERROR); } 508 bool suppressFuncError() const { return flags.isSet(SUPPRESS_FUNC_ERROR); } 509 void setBlockCached() { flags.set(BLOCK_CACHED); } 510 bool isBlockCached() const { return flags.isSet(BLOCK_CACHED); } 511 512 // Network error conditions... encapsulate them as methods since 513 // their encoding keeps changing (from result field to command 514 // field, etc.) 515 void 516 setBadAddress() 517 { 518 assert(isResponse()); 519 cmd = MemCmd::BadAddressError; 520 } 521 522 bool hadBadAddress() const { return cmd == MemCmd::BadAddressError; } 523 void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; } 524 525 Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; } 526 /** 527 * Update the address of this packet mid-transaction. This is used 528 * by the address mapper to change an already set address to a new 529 * one based on the system configuration. It is intended to remap 530 * an existing address, so it asserts that the current address is 531 * valid. 532 */ 533 void setAddr(Addr _addr) { assert(flags.isSet(VALID_ADDR)); addr = _addr; } 534 535 unsigned getSize() const { assert(flags.isSet(VALID_SIZE)); return size; } 536 Addr getOffset(int blkSize) const { return getAddr() & (Addr)(blkSize - 1); } 537 538 bool isSecure() const 539 { 540 assert(flags.isSet(VALID_ADDR)); 541 return _isSecure; 542 } 543 544 /** 545 * It has been determined that the SC packet should successfully update 546 * memory. Therefore, convert this SC packet to a normal write. 547 */ 548 void 549 convertScToWrite() 550 { 551 assert(isLLSC()); 552 assert(isWrite()); 553 cmd = MemCmd::WriteReq; 554 } 555 556 /** 557 * When ruby is in use, Ruby will monitor the cache line and thus M5 558 * phys memory should treat LL ops as normal reads. 559 */ 560 void 561 convertLlToRead() 562 { 563 assert(isLLSC()); 564 assert(isRead()); 565 cmd = MemCmd::ReadReq; 566 } 567 568 /** 569 * Constructor. Note that a Request object must be constructed 570 * first, but the Requests's physical address and size fields need 571 * not be valid. The command must be supplied. 572 */ 573 Packet(const RequestPtr _req, MemCmd _cmd) 574 : cmd(_cmd), req(_req), data(nullptr), addr(0), _isSecure(false), 575 size(0), headerDelay(0), payloadDelay(0), 576 senderState(NULL) 577 { 578 if (req->hasPaddr()) { 579 addr = req->getPaddr(); 580 flags.set(VALID_ADDR); 581 _isSecure = req->isSecure(); 582 } 583 if (req->hasSize()) { 584 size = req->getSize(); 585 flags.set(VALID_SIZE); 586 } 587 } 588 589 /** 590 * Alternate constructor if you are trying to create a packet with 591 * a request that is for a whole block, not the address from the 592 * req. this allows for overriding the size/addr of the req. 593 */ 594 Packet(const RequestPtr _req, MemCmd _cmd, int _blkSize) 595 : cmd(_cmd), req(_req), data(nullptr), addr(0), _isSecure(false), 596 headerDelay(0), payloadDelay(0), 597 senderState(NULL) 598 { 599 if (req->hasPaddr()) { 600 addr = req->getPaddr() & ~(_blkSize - 1); 601 flags.set(VALID_ADDR); 602 _isSecure = req->isSecure(); 603 } 604 size = _blkSize; 605 flags.set(VALID_SIZE); 606 } 607 608 /** 609 * Alternate constructor for copying a packet. Copy all fields 610 * *except* if the original packet's data was dynamic, don't copy 611 * that, as we can't guarantee that the new packet's lifetime is 612 * less than that of the original packet. In this case the new 613 * packet should allocate its own data. 614 */ 615 Packet(PacketPtr pkt, bool clear_flags, bool alloc_data) 616 : cmd(pkt->cmd), req(pkt->req), 617 data(nullptr), 618 addr(pkt->addr), _isSecure(pkt->_isSecure), size(pkt->size), 619 bytesValid(pkt->bytesValid), 620 headerDelay(pkt->headerDelay), 621 payloadDelay(pkt->payloadDelay), 622 senderState(pkt->senderState) 623 { 624 if (!clear_flags) 625 flags.set(pkt->flags & COPY_FLAGS); 626 627 flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE)); 628 629 // should we allocate space for data, or not, the express 630 // snoops do not need to carry any data as they only serve to 631 // co-ordinate state changes 632 if (alloc_data) { 633 // even if asked to allocate data, if the original packet 634 // holds static data, then the sender will not be doing 635 // any memcpy on receiving the response, thus we simply 636 // carry the pointer forward 637 if (pkt->flags.isSet(STATIC_DATA)) { 638 data = pkt->data; 639 flags.set(STATIC_DATA); 640 } else { 641 allocate(); 642 } 643 } 644 } 645 646 /** 647 * Generate the appropriate read MemCmd based on the Request flags. 648 */ 649 static MemCmd 650 makeReadCmd(const RequestPtr req) 651 { 652 if (req->isLLSC()) 653 return MemCmd::LoadLockedReq; 654 else if (req->isPrefetch()) 655 return MemCmd::SoftPFReq; 656 else 657 return MemCmd::ReadReq; 658 } 659 660 /** 661 * Generate the appropriate write MemCmd based on the Request flags. 662 */ 663 static MemCmd 664 makeWriteCmd(const RequestPtr req) 665 { 666 if (req->isLLSC()) 667 return MemCmd::StoreCondReq; 668 else if (req->isSwap()) 669 return MemCmd::SwapReq; 670 else 671 return MemCmd::WriteReq; 672 } 673 674 /** 675 * Constructor-like methods that return Packets based on Request objects. 676 * Fine-tune the MemCmd type if it's not a vanilla read or write. 677 */ 678 static PacketPtr 679 createRead(const RequestPtr req) 680 { 681 return new Packet(req, makeReadCmd(req)); 682 } 683 684 static PacketPtr 685 createWrite(const RequestPtr req) 686 { 687 return new Packet(req, makeWriteCmd(req)); 688 } 689 690 /** 691 * clean up packet variables 692 */ 693 ~Packet() 694 { 695 // If this is a request packet for which there's no response, 696 // delete the request object here, since the requester will 697 // never get the chance. 698 if (req && isRequest() && !needsResponse()) 699 delete req; 700 deleteData(); 701 } 702 703 /** 704 * Take a request packet and modify it in place to be suitable for 705 * returning as a response to that request. 706 */ 707 void 708 makeResponse() 709 { 710 assert(needsResponse()); 711 assert(isRequest()); 712 origCmd = cmd; 713 cmd = cmd.responseCommand(); 714 715 // responses are never express, even if the snoop that 716 // triggered them was 717 flags.clear(EXPRESS_SNOOP); 718 } 719 720 void 721 makeAtomicResponse() 722 { 723 makeResponse(); 724 } 725 726 void 727 makeTimingResponse() 728 { 729 makeResponse(); 730 } 731 732 void 733 setFunctionalResponseStatus(bool success) 734 { 735 if (!success) { 736 if (isWrite()) { 737 cmd = MemCmd::FunctionalWriteError; 738 } else { 739 cmd = MemCmd::FunctionalReadError; 740 } 741 } 742 } 743 744 void 745 setSize(unsigned size) 746 { 747 assert(!flags.isSet(VALID_SIZE)); 748 749 this->size = size; 750 flags.set(VALID_SIZE); 751 } 752 753 754 /** 755 * Set the data pointer to the following value that should not be 756 * freed. Static data allows us to do a single memcpy even if 757 * multiple packets are required to get from source to destination 758 * and back. In essence the pointer is set calling dataStatic on 759 * the original packet, and whenever this packet is copied and 760 * forwarded the same pointer is passed on. When a packet 761 * eventually reaches the destination holding the data, it is 762 * copied once into the location originally set. On the way back 763 * to the source, no copies are necessary. 764 */ 765 template <typename T> 766 void 767 dataStatic(T *p) 768 { 769 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 770 data = (PacketDataPtr)p; 771 flags.set(STATIC_DATA); 772 } 773 774 /** 775 * Set the data pointer to the following value that should not be 776 * freed. This version of the function allows the pointer passed 777 * to us to be const. To avoid issues down the line we cast the 778 * constness away, the alternative would be to keep both a const 779 * and non-const data pointer and cleverly choose between 780 * them. Note that this is only allowed for static data. 781 */ 782 template <typename T> 783 void 784 dataStaticConst(const T *p) 785 { 786 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 787 data = const_cast<PacketDataPtr>(p); 788 flags.set(STATIC_DATA); 789 } 790 791 /** 792 * Set the data pointer to a value that should have delete [] 793 * called on it. Dynamic data is local to this packet, and as the 794 * packet travels from source to destination, forwarded packets 795 * will allocate their own data. When a packet reaches the final 796 * destination it will populate the dynamic data of that specific 797 * packet, and on the way back towards the source, memcpy will be 798 * invoked in every step where a new packet was created e.g. in 799 * the caches. Ultimately when the response reaches the source a 800 * final memcpy is needed to extract the data from the packet 801 * before it is deallocated. 802 */ 803 template <typename T> 804 void 805 dataDynamic(T *p) 806 { 807 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 808 data = (PacketDataPtr)p; 809 flags.set(DYNAMIC_DATA); 810 } 811 812 /** 813 * get a pointer to the data ptr. 814 */ 815 template <typename T> 816 T* 817 getPtr() 818 { 819 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA)); 820 return (T*)data; 821 } 822 823 template <typename T> 824 const T* 825 getConstPtr() const 826 { 827 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA)); 828 return (const T*)data; 829 } 830 831 /** 832 * return the value of what is pointed to in the packet. 833 */ 834 template <typename T> 835 T get() const; 836 837 /** 838 * set the value in the data pointer to v. 839 */ 840 template <typename T> 841 void set(T v); 842 843 /** 844 * Copy data into the packet from the provided pointer. 845 */ 846 void 847 setData(const uint8_t *p) 848 { 849 // we should never be copying data onto itself, which means we 850 // must idenfity packets with static data, as they carry the 851 // same pointer from source to destination and back 852 assert(p != getPtr<uint8_t>() || flags.isSet(STATIC_DATA)); 853 854 if (p != getPtr<uint8_t>()) 855 // for packet with allocated dynamic data, we copy data from 856 // one to the other, e.g. a forwarded response to a response 857 std::memcpy(getPtr<uint8_t>(), p, getSize()); 858 } 859 860 /** 861 * Copy data into the packet from the provided block pointer, 862 * which is aligned to the given block size. 863 */ 864 void 865 setDataFromBlock(const uint8_t *blk_data, int blkSize) 866 { 867 setData(blk_data + getOffset(blkSize)); 868 } 869 870 /** 871 * Copy data from the packet to the provided block pointer, which 872 * is aligned to the given block size. 873 */ 874 void 875 writeData(uint8_t *p) const 876 { 877 std::memcpy(p, getConstPtr<uint8_t>(), getSize()); 878 } 879 880 /** 881 * Copy data from the packet to the memory at the provided pointer. 882 */ 883 void 884 writeDataToBlock(uint8_t *blk_data, int blkSize) const 885 { 886 writeData(blk_data + getOffset(blkSize)); 887 } 888 889 /** 890 * delete the data pointed to in the data pointer. Ok to call to 891 * matter how data was allocted. 892 */ 893 void 894 deleteData() 895 { 896 if (flags.isSet(DYNAMIC_DATA)) 897 delete [] data; 898 899 flags.clear(STATIC_DATA|DYNAMIC_DATA); 900 data = NULL; 901 } 902 903 /** Allocate memory for the packet. */ 904 void 905 allocate() 906 { 907 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 908 flags.set(DYNAMIC_DATA); 909 data = new uint8_t[getSize()]; 910 } 911 912 /** 913 * Check a functional request against a memory value stored in 914 * another packet (i.e. an in-transit request or 915 * response). Returns true if the current packet is a read, and 916 * the other packet provides the data, which is then copied to the 917 * current packet. If the current packet is a write, and the other 918 * packet intersects this one, then we update the data 919 * accordingly. 920 */ 921 bool 922 checkFunctional(PacketPtr other) 923 { 924 // all packets that are carrying a payload should have a valid 925 // data pointer 926 return checkFunctional(other, other->getAddr(), other->isSecure(), 927 other->getSize(), 928 other->hasData() ? 929 other->getPtr<uint8_t>() : NULL); 930 } 931 932 /** 933 * Check a functional request against a memory value represented 934 * by a base/size pair and an associated data array. If the 935 * current packet is a read, it may be satisfied by the memory 936 * value. If the current packet is a write, it may update the 937 * memory value. 938 */ 939 bool 940 checkFunctional(Printable *obj, Addr base, bool is_secure, int size, 941 uint8_t *_data); 942 943 /** 944 * Push label for PrintReq (safe to call unconditionally). 945 */ 946 void 947 pushLabel(const std::string &lbl) 948 { 949 if (isPrint()) 950 safe_cast<PrintReqState*>(senderState)->pushLabel(lbl); 951 } 952 953 /** 954 * Pop label for PrintReq (safe to call unconditionally). 955 */ 956 void 957 popLabel() 958 { 959 if (isPrint()) 960 safe_cast<PrintReqState*>(senderState)->popLabel(); 961 } 962 963 void print(std::ostream &o, int verbosity = 0, 964 const std::string &prefix = "") const; 965 966 /** 967 * A no-args wrapper of print(std::ostream...) 968 * meant to be invoked from DPRINTFs 969 * avoiding string overheads in fast mode 970 * @return string with the request's type and start<->end addresses 971 */ 972 std::string print() const; 973}; 974 975#endif //__MEM_PACKET_HH 976