packet.hh revision 10885
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 CleanEvict, 91 SoftPFReq, 92 HardPFReq, 93 SoftPFResp, 94 HardPFResp, 95 WriteInvalidateReq, 96 WriteInvalidateResp, 97 UpgradeReq, 98 SCUpgradeReq, // Special "weak" upgrade for StoreCond 99 UpgradeResp, 100 SCUpgradeFailReq, // Failed SCUpgradeReq in MSHR (never sent) 101 UpgradeFailResp, // Valid for SCUpgradeReq only 102 ReadExReq, 103 ReadExResp, 104 ReadCleanReq, 105 ReadSharedReq, 106 LoadLockedReq, 107 StoreCondReq, 108 StoreCondFailReq, // Failed StoreCondReq in MSHR (never sent) 109 StoreCondResp, 110 SwapReq, 111 SwapResp, 112 MessageReq, 113 MessageResp, 114 // Error responses 115 // @TODO these should be classified as responses rather than 116 // requests; coding them as requests initially for backwards 117 // compatibility 118 InvalidDestError, // packet dest field invalid 119 BadAddressError, // memory address invalid 120 FunctionalReadError, // unable to fulfill functional read 121 FunctionalWriteError, // unable to fulfill functional write 122 // Fake simulator-only commands 123 PrintReq, // Print state matching address 124 FlushReq, //request for a cache flush 125 InvalidationReq, // request for address to be invalidated from lsq 126 NUM_MEM_CMDS 127 }; 128 129 private: 130 /** 131 * List of command attributes. 132 */ 133 enum Attribute 134 { 135 IsRead, //!< Data flows from responder to requester 136 IsWrite, //!< Data flows from requester to responder 137 IsUpgrade, 138 IsInvalidate, 139 NeedsExclusive, //!< Requires exclusive copy to complete in-cache 140 IsRequest, //!< Issued by requester 141 IsResponse, //!< Issue by responder 142 NeedsResponse, //!< Requester needs response from target 143 IsSWPrefetch, 144 IsHWPrefetch, 145 IsLlsc, //!< Alpha/MIPS LL or SC access 146 HasData, //!< There is an associated payload 147 IsError, //!< Error response 148 IsPrint, //!< Print state matching address (for debugging) 149 IsFlush, //!< Flush the address from caches 150 NUM_COMMAND_ATTRIBUTES 151 }; 152 153 /** 154 * Structure that defines attributes and other data associated 155 * with a Command. 156 */ 157 struct CommandInfo 158 { 159 /// Set of attribute flags. 160 const std::bitset<NUM_COMMAND_ATTRIBUTES> attributes; 161 /// Corresponding response for requests; InvalidCmd if no 162 /// response is applicable. 163 const Command response; 164 /// String representation (for printing) 165 const std::string str; 166 }; 167 168 /// Array to map Command enum to associated info. 169 static const CommandInfo commandInfo[]; 170 171 private: 172 173 Command cmd; 174 175 bool 176 testCmdAttrib(MemCmd::Attribute attrib) const 177 { 178 return commandInfo[cmd].attributes[attrib] != 0; 179 } 180 181 public: 182 183 bool isRead() const { return testCmdAttrib(IsRead); } 184 bool isWrite() const { return testCmdAttrib(IsWrite); } 185 bool isUpgrade() const { return testCmdAttrib(IsUpgrade); } 186 bool isRequest() const { return testCmdAttrib(IsRequest); } 187 bool isResponse() const { return testCmdAttrib(IsResponse); } 188 bool needsExclusive() const { return testCmdAttrib(NeedsExclusive); } 189 bool needsResponse() const { return testCmdAttrib(NeedsResponse); } 190 bool isInvalidate() const { return testCmdAttrib(IsInvalidate); } 191 bool isWriteInvalidate() const { return testCmdAttrib(IsWrite) && 192 testCmdAttrib(IsInvalidate); } 193 194 /** 195 * Check if this particular packet type carries payload data. Note 196 * that this does not reflect if the data pointer of the packet is 197 * valid or not. 198 */ 199 bool hasData() const { return testCmdAttrib(HasData); } 200 bool isLLSC() const { return testCmdAttrib(IsLlsc); } 201 bool isSWPrefetch() const { return testCmdAttrib(IsSWPrefetch); } 202 bool isHWPrefetch() const { return testCmdAttrib(IsHWPrefetch); } 203 bool isPrefetch() const { return testCmdAttrib(IsSWPrefetch) || 204 testCmdAttrib(IsHWPrefetch); } 205 bool isError() const { return testCmdAttrib(IsError); } 206 bool isPrint() const { return testCmdAttrib(IsPrint); } 207 bool isFlush() const { return testCmdAttrib(IsFlush); } 208 209 const Command 210 responseCommand() const 211 { 212 return commandInfo[cmd].response; 213 } 214 215 /// Return the string to a cmd given by idx. 216 const std::string &toString() const { return commandInfo[cmd].str; } 217 int toInt() const { return (int)cmd; } 218 219 MemCmd(Command _cmd) : cmd(_cmd) { } 220 MemCmd(int _cmd) : cmd((Command)_cmd) { } 221 MemCmd() : cmd(InvalidCmd) { } 222 223 bool operator==(MemCmd c2) const { return (cmd == c2.cmd); } 224 bool operator!=(MemCmd c2) const { return (cmd != c2.cmd); } 225}; 226 227/** 228 * A Packet is used to encapsulate a transfer between two objects in 229 * the memory system (e.g., the L1 and L2 cache). (In contrast, a 230 * single Request travels all the way from the requester to the 231 * ultimate destination and back, possibly being conveyed by several 232 * different Packets along the way.) 233 */ 234class Packet : public Printable 235{ 236 public: 237 typedef uint32_t FlagsType; 238 typedef ::Flags<FlagsType> Flags; 239 240 private: 241 static const FlagsType PUBLIC_FLAGS = 0x00000000; 242 static const FlagsType PRIVATE_FLAGS = 0x00007F0F; 243 static const FlagsType COPY_FLAGS = 0x0000000F; 244 245 static const FlagsType SHARED = 0x00000001; 246 // Special control flags 247 /// Special timing-mode atomic snoop for multi-level coherence. 248 static const FlagsType EXPRESS_SNOOP = 0x00000002; 249 /// Does supplier have exclusive copy? 250 /// Useful for multi-level coherence. 251 static const FlagsType SUPPLY_EXCLUSIVE = 0x00000004; 252 // Snoop response flags 253 static const FlagsType MEM_INHIBIT = 0x00000008; 254 /// Are the 'addr' and 'size' fields valid? 255 static const FlagsType VALID_ADDR = 0x00000100; 256 static const FlagsType VALID_SIZE = 0x00000200; 257 /// Is the data pointer set to a value that shouldn't be freed 258 /// when the packet is destroyed? 259 static const FlagsType STATIC_DATA = 0x00001000; 260 /// The data pointer points to a value that should be freed when 261 /// the packet is destroyed. The pointer is assumed to be pointing 262 /// to an array, and delete [] is consequently called 263 static const FlagsType DYNAMIC_DATA = 0x00002000; 264 /// suppress the error if this packet encounters a functional 265 /// access failure. 266 static const FlagsType SUPPRESS_FUNC_ERROR = 0x00008000; 267 // Signal block present to squash prefetch and cache evict packets 268 // through express snoop flag 269 static const FlagsType BLOCK_CACHED = 0x00010000; 270 271 Flags flags; 272 273 public: 274 typedef MemCmd::Command Command; 275 276 /// The command field of the packet. 277 MemCmd cmd; 278 279 /// A pointer to the original request. 280 const RequestPtr req; 281 282 private: 283 /** 284 * A pointer to the data being transfered. It can be differnt 285 * sizes at each level of the heirarchy so it belongs in the 286 * packet, not request. This may or may not be populated when a 287 * responder recieves the packet. If not populated it memory should 288 * be allocated. 289 */ 290 PacketDataPtr data; 291 292 /// The address of the request. This address could be virtual or 293 /// physical, depending on the system configuration. 294 Addr addr; 295 296 /// True if the request targets the secure memory space. 297 bool _isSecure; 298 299 /// The size of the request or transfer. 300 unsigned size; 301 302 /** 303 * The original value of the command field. Only valid when the 304 * current command field is an error condition; in that case, the 305 * previous contents of the command field are copied here. This 306 * field is *not* set on non-error responses. 307 */ 308 MemCmd origCmd; 309 310 /** 311 * Track the bytes found that satisfy a functional read. 312 */ 313 std::vector<bool> bytesValid; 314 315 public: 316 317 /** 318 * The extra delay from seeing the packet until the header is 319 * transmitted. This delay is used to communicate the crossbar 320 * forwarding latency to the neighbouring object (e.g. a cache) 321 * that actually makes the packet wait. As the delay is relative, 322 * a 32-bit unsigned should be sufficient. 323 */ 324 uint32_t headerDelay; 325 326 /** 327 * The extra pipelining delay from seeing the packet until the end of 328 * payload is transmitted by the component that provided it (if 329 * any). This includes the header delay. Similar to the header 330 * delay, this is used to make up for the fact that the 331 * crossbar does not make the packet wait. As the delay is 332 * relative, a 32-bit unsigned should be sufficient. 333 */ 334 uint32_t payloadDelay; 335 336 /** 337 * A virtual base opaque structure used to hold state associated 338 * with the packet (e.g., an MSHR), specific to a MemObject that 339 * sees the packet. A pointer to this state is returned in the 340 * packet's response so that the MemObject in question can quickly 341 * look up the state needed to process it. A specific subclass 342 * would be derived from this to carry state specific to a 343 * particular sending device. 344 * 345 * As multiple MemObjects may add their SenderState throughout the 346 * memory system, the SenderStates create a stack, where a 347 * MemObject can add a new Senderstate, as long as the 348 * predecessing SenderState is restored when the response comes 349 * back. For this reason, the predecessor should always be 350 * populated with the current SenderState of a packet before 351 * modifying the senderState field in the request packet. 352 */ 353 struct SenderState 354 { 355 SenderState* predecessor; 356 SenderState() : predecessor(NULL) {} 357 virtual ~SenderState() {} 358 }; 359 360 /** 361 * Object used to maintain state of a PrintReq. The senderState 362 * field of a PrintReq should always be of this type. 363 */ 364 class PrintReqState : public SenderState 365 { 366 private: 367 /** 368 * An entry in the label stack. 369 */ 370 struct LabelStackEntry 371 { 372 const std::string label; 373 std::string *prefix; 374 bool labelPrinted; 375 LabelStackEntry(const std::string &_label, std::string *_prefix); 376 }; 377 378 typedef std::list<LabelStackEntry> LabelStack; 379 LabelStack labelStack; 380 381 std::string *curPrefixPtr; 382 383 public: 384 std::ostream &os; 385 const int verbosity; 386 387 PrintReqState(std::ostream &os, int verbosity = 0); 388 ~PrintReqState(); 389 390 /** 391 * Returns the current line prefix. 392 */ 393 const std::string &curPrefix() { return *curPrefixPtr; } 394 395 /** 396 * Push a label onto the label stack, and prepend the given 397 * prefix string onto the current prefix. Labels will only be 398 * printed if an object within the label's scope is printed. 399 */ 400 void pushLabel(const std::string &lbl, 401 const std::string &prefix = " "); 402 403 /** 404 * Pop a label off the label stack. 405 */ 406 void popLabel(); 407 408 /** 409 * Print all of the pending unprinted labels on the 410 * stack. Called by printObj(), so normally not called by 411 * users unless bypassing printObj(). 412 */ 413 void printLabels(); 414 415 /** 416 * Print a Printable object to os, because it matched the 417 * address on a PrintReq. 418 */ 419 void printObj(Printable *obj); 420 }; 421 422 /** 423 * This packet's sender state. Devices should use dynamic_cast<> 424 * to cast to the state appropriate to the sender. The intent of 425 * this variable is to allow a device to attach extra information 426 * to a request. A response packet must return the sender state 427 * that was attached to the original request (even if a new packet 428 * is created). 429 */ 430 SenderState *senderState; 431 432 /** 433 * Push a new sender state to the packet and make the current 434 * sender state the predecessor of the new one. This should be 435 * prefered over direct manipulation of the senderState member 436 * variable. 437 * 438 * @param sender_state SenderState to push at the top of the stack 439 */ 440 void pushSenderState(SenderState *sender_state); 441 442 /** 443 * Pop the top of the state stack and return a pointer to it. This 444 * assumes the current sender state is not NULL. This should be 445 * preferred over direct manipulation of the senderState member 446 * variable. 447 * 448 * @return The current top of the stack 449 */ 450 SenderState *popSenderState(); 451 452 /** 453 * Go through the sender state stack and return the first instance 454 * that is of type T (as determined by a dynamic_cast). If there 455 * is no sender state of type T, NULL is returned. 456 * 457 * @return The topmost state of type T 458 */ 459 template <typename T> 460 T * findNextSenderState() const 461 { 462 T *t = NULL; 463 SenderState* sender_state = senderState; 464 while (t == NULL && sender_state != NULL) { 465 t = dynamic_cast<T*>(sender_state); 466 sender_state = sender_state->predecessor; 467 } 468 return t; 469 } 470 471 /// Return the string name of the cmd field (for debugging and 472 /// tracing). 473 const std::string &cmdString() const { return cmd.toString(); } 474 475 /// Return the index of this command. 476 inline int cmdToIndex() const { return cmd.toInt(); } 477 478 bool isRead() const { return cmd.isRead(); } 479 bool isWrite() const { return cmd.isWrite(); } 480 bool isUpgrade() const { return cmd.isUpgrade(); } 481 bool isRequest() const { return cmd.isRequest(); } 482 bool isResponse() const { return cmd.isResponse(); } 483 bool needsExclusive() const { return cmd.needsExclusive(); } 484 bool needsResponse() const { return cmd.needsResponse(); } 485 bool isInvalidate() const { return cmd.isInvalidate(); } 486 bool isWriteInvalidate() const { return cmd.isWriteInvalidate(); } 487 bool hasData() const { return cmd.hasData(); } 488 bool isLLSC() const { return cmd.isLLSC(); } 489 bool isError() const { return cmd.isError(); } 490 bool isPrint() const { return cmd.isPrint(); } 491 bool isFlush() const { return cmd.isFlush(); } 492 493 // Snoop flags 494 void assertMemInhibit() 495 { 496 assert(isRequest()); 497 assert(!flags.isSet(MEM_INHIBIT)); 498 flags.set(MEM_INHIBIT); 499 } 500 bool memInhibitAsserted() const { return flags.isSet(MEM_INHIBIT); } 501 void assertShared() { flags.set(SHARED); } 502 bool sharedAsserted() const { return flags.isSet(SHARED); } 503 504 // Special control flags 505 void setExpressSnoop() { flags.set(EXPRESS_SNOOP); } 506 bool isExpressSnoop() const { return flags.isSet(EXPRESS_SNOOP); } 507 void setSupplyExclusive() { flags.set(SUPPLY_EXCLUSIVE); } 508 void clearSupplyExclusive() { flags.clear(SUPPLY_EXCLUSIVE); } 509 bool isSupplyExclusive() const { return flags.isSet(SUPPLY_EXCLUSIVE); } 510 void setSuppressFuncError() { flags.set(SUPPRESS_FUNC_ERROR); } 511 bool suppressFuncError() const { return flags.isSet(SUPPRESS_FUNC_ERROR); } 512 void setBlockCached() { flags.set(BLOCK_CACHED); } 513 bool isBlockCached() const { return flags.isSet(BLOCK_CACHED); } 514 void clearBlockCached() { flags.clear(BLOCK_CACHED); } 515 516 // Network error conditions... encapsulate them as methods since 517 // their encoding keeps changing (from result field to command 518 // field, etc.) 519 void 520 setBadAddress() 521 { 522 assert(isResponse()); 523 cmd = MemCmd::BadAddressError; 524 } 525 526 bool hadBadAddress() const { return cmd == MemCmd::BadAddressError; } 527 void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; } 528 529 Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; } 530 /** 531 * Update the address of this packet mid-transaction. This is used 532 * by the address mapper to change an already set address to a new 533 * one based on the system configuration. It is intended to remap 534 * an existing address, so it asserts that the current address is 535 * valid. 536 */ 537 void setAddr(Addr _addr) { assert(flags.isSet(VALID_ADDR)); addr = _addr; } 538 539 unsigned getSize() const { assert(flags.isSet(VALID_SIZE)); return size; } 540 Addr getOffset(int blkSize) const { return getAddr() & (Addr)(blkSize - 1); } 541 542 bool isSecure() const 543 { 544 assert(flags.isSet(VALID_ADDR)); 545 return _isSecure; 546 } 547 548 /** 549 * It has been determined that the SC packet should successfully update 550 * memory. Therefore, convert this SC packet to a normal write. 551 */ 552 void 553 convertScToWrite() 554 { 555 assert(isLLSC()); 556 assert(isWrite()); 557 cmd = MemCmd::WriteReq; 558 } 559 560 /** 561 * When ruby is in use, Ruby will monitor the cache line and thus M5 562 * phys memory should treat LL ops as normal reads. 563 */ 564 void 565 convertLlToRead() 566 { 567 assert(isLLSC()); 568 assert(isRead()); 569 cmd = MemCmd::ReadReq; 570 } 571 572 /** 573 * Constructor. Note that a Request object must be constructed 574 * first, but the Requests's physical address and size fields need 575 * not be valid. The command must be supplied. 576 */ 577 Packet(const RequestPtr _req, MemCmd _cmd) 578 : cmd(_cmd), req(_req), data(nullptr), addr(0), _isSecure(false), 579 size(0), headerDelay(0), payloadDelay(0), 580 senderState(NULL) 581 { 582 if (req->hasPaddr()) { 583 addr = req->getPaddr(); 584 flags.set(VALID_ADDR); 585 _isSecure = req->isSecure(); 586 } 587 if (req->hasSize()) { 588 size = req->getSize(); 589 flags.set(VALID_SIZE); 590 } 591 } 592 593 /** 594 * Alternate constructor if you are trying to create a packet with 595 * a request that is for a whole block, not the address from the 596 * req. this allows for overriding the size/addr of the req. 597 */ 598 Packet(const RequestPtr _req, MemCmd _cmd, int _blkSize) 599 : cmd(_cmd), req(_req), data(nullptr), addr(0), _isSecure(false), 600 headerDelay(0), payloadDelay(0), 601 senderState(NULL) 602 { 603 if (req->hasPaddr()) { 604 addr = req->getPaddr() & ~(_blkSize - 1); 605 flags.set(VALID_ADDR); 606 _isSecure = req->isSecure(); 607 } 608 size = _blkSize; 609 flags.set(VALID_SIZE); 610 } 611 612 /** 613 * Alternate constructor for copying a packet. Copy all fields 614 * *except* if the original packet's data was dynamic, don't copy 615 * that, as we can't guarantee that the new packet's lifetime is 616 * less than that of the original packet. In this case the new 617 * packet should allocate its own data. 618 */ 619 Packet(PacketPtr pkt, bool clear_flags, bool alloc_data) 620 : cmd(pkt->cmd), req(pkt->req), 621 data(nullptr), 622 addr(pkt->addr), _isSecure(pkt->_isSecure), size(pkt->size), 623 bytesValid(pkt->bytesValid), 624 headerDelay(pkt->headerDelay), 625 payloadDelay(pkt->payloadDelay), 626 senderState(pkt->senderState) 627 { 628 if (!clear_flags) 629 flags.set(pkt->flags & COPY_FLAGS); 630 631 flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE)); 632 633 // should we allocate space for data, or not, the express 634 // snoops do not need to carry any data as they only serve to 635 // co-ordinate state changes 636 if (alloc_data) { 637 // even if asked to allocate data, if the original packet 638 // holds static data, then the sender will not be doing 639 // any memcpy on receiving the response, thus we simply 640 // carry the pointer forward 641 if (pkt->flags.isSet(STATIC_DATA)) { 642 data = pkt->data; 643 flags.set(STATIC_DATA); 644 } else { 645 allocate(); 646 } 647 } 648 } 649 650 /** 651 * Generate the appropriate read MemCmd based on the Request flags. 652 */ 653 static MemCmd 654 makeReadCmd(const RequestPtr req) 655 { 656 if (req->isLLSC()) 657 return MemCmd::LoadLockedReq; 658 else if (req->isPrefetch()) 659 return MemCmd::SoftPFReq; 660 else 661 return MemCmd::ReadReq; 662 } 663 664 /** 665 * Generate the appropriate write MemCmd based on the Request flags. 666 */ 667 static MemCmd 668 makeWriteCmd(const RequestPtr req) 669 { 670 if (req->isLLSC()) 671 return MemCmd::StoreCondReq; 672 else if (req->isSwap()) 673 return MemCmd::SwapReq; 674 else 675 return MemCmd::WriteReq; 676 } 677 678 /** 679 * Constructor-like methods that return Packets based on Request objects. 680 * Fine-tune the MemCmd type if it's not a vanilla read or write. 681 */ 682 static PacketPtr 683 createRead(const RequestPtr req) 684 { 685 return new Packet(req, makeReadCmd(req)); 686 } 687 688 static PacketPtr 689 createWrite(const RequestPtr req) 690 { 691 return new Packet(req, makeWriteCmd(req)); 692 } 693 694 /** 695 * clean up packet variables 696 */ 697 ~Packet() 698 { 699 // Delete the request object if this is a request packet which 700 // does not need a response, because the requester will not get 701 // a chance. If the request packet needs a response then the 702 // request will be deleted on receipt of the response 703 // packet. We also make sure to never delete the request for 704 // express snoops, even for cases when responses are not 705 // needed (CleanEvict and Writeback), since the snoop packet 706 // re-uses the same request. 707 if (req && isRequest() && !needsResponse() && 708 !isExpressSnoop()) { 709 delete req; 710 } 711 deleteData(); 712 } 713 714 /** 715 * Take a request packet and modify it in place to be suitable for 716 * returning as a response to that request. 717 */ 718 void 719 makeResponse() 720 { 721 assert(needsResponse()); 722 assert(isRequest()); 723 origCmd = cmd; 724 cmd = cmd.responseCommand(); 725 726 // responses are never express, even if the snoop that 727 // triggered them was 728 flags.clear(EXPRESS_SNOOP); 729 } 730 731 void 732 makeAtomicResponse() 733 { 734 makeResponse(); 735 } 736 737 void 738 makeTimingResponse() 739 { 740 makeResponse(); 741 } 742 743 void 744 setFunctionalResponseStatus(bool success) 745 { 746 if (!success) { 747 if (isWrite()) { 748 cmd = MemCmd::FunctionalWriteError; 749 } else { 750 cmd = MemCmd::FunctionalReadError; 751 } 752 } 753 } 754 755 void 756 setSize(unsigned size) 757 { 758 assert(!flags.isSet(VALID_SIZE)); 759 760 this->size = size; 761 flags.set(VALID_SIZE); 762 } 763 764 765 /** 766 * Set the data pointer to the following value that should not be 767 * freed. Static data allows us to do a single memcpy even if 768 * multiple packets are required to get from source to destination 769 * and back. In essence the pointer is set calling dataStatic on 770 * the original packet, and whenever this packet is copied and 771 * forwarded the same pointer is passed on. When a packet 772 * eventually reaches the destination holding the data, it is 773 * copied once into the location originally set. On the way back 774 * to the source, no copies are necessary. 775 */ 776 template <typename T> 777 void 778 dataStatic(T *p) 779 { 780 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 781 data = (PacketDataPtr)p; 782 flags.set(STATIC_DATA); 783 } 784 785 /** 786 * Set the data pointer to the following value that should not be 787 * freed. This version of the function allows the pointer passed 788 * to us to be const. To avoid issues down the line we cast the 789 * constness away, the alternative would be to keep both a const 790 * and non-const data pointer and cleverly choose between 791 * them. Note that this is only allowed for static data. 792 */ 793 template <typename T> 794 void 795 dataStaticConst(const T *p) 796 { 797 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 798 data = const_cast<PacketDataPtr>(p); 799 flags.set(STATIC_DATA); 800 } 801 802 /** 803 * Set the data pointer to a value that should have delete [] 804 * called on it. Dynamic data is local to this packet, and as the 805 * packet travels from source to destination, forwarded packets 806 * will allocate their own data. When a packet reaches the final 807 * destination it will populate the dynamic data of that specific 808 * packet, and on the way back towards the source, memcpy will be 809 * invoked in every step where a new packet was created e.g. in 810 * the caches. Ultimately when the response reaches the source a 811 * final memcpy is needed to extract the data from the packet 812 * before it is deallocated. 813 */ 814 template <typename T> 815 void 816 dataDynamic(T *p) 817 { 818 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 819 data = (PacketDataPtr)p; 820 flags.set(DYNAMIC_DATA); 821 } 822 823 /** 824 * get a pointer to the data ptr. 825 */ 826 template <typename T> 827 T* 828 getPtr() 829 { 830 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA)); 831 return (T*)data; 832 } 833 834 template <typename T> 835 const T* 836 getConstPtr() const 837 { 838 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA)); 839 return (const T*)data; 840 } 841 842 /** 843 * return the value of what is pointed to in the packet. 844 */ 845 template <typename T> 846 T get() const; 847 848 /** 849 * set the value in the data pointer to v. 850 */ 851 template <typename T> 852 void set(T v); 853 854 /** 855 * Copy data into the packet from the provided pointer. 856 */ 857 void 858 setData(const uint8_t *p) 859 { 860 // we should never be copying data onto itself, which means we 861 // must idenfity packets with static data, as they carry the 862 // same pointer from source to destination and back 863 assert(p != getPtr<uint8_t>() || flags.isSet(STATIC_DATA)); 864 865 if (p != getPtr<uint8_t>()) 866 // for packet with allocated dynamic data, we copy data from 867 // one to the other, e.g. a forwarded response to a response 868 std::memcpy(getPtr<uint8_t>(), p, getSize()); 869 } 870 871 /** 872 * Copy data into the packet from the provided block pointer, 873 * which is aligned to the given block size. 874 */ 875 void 876 setDataFromBlock(const uint8_t *blk_data, int blkSize) 877 { 878 setData(blk_data + getOffset(blkSize)); 879 } 880 881 /** 882 * Copy data from the packet to the provided block pointer, which 883 * is aligned to the given block size. 884 */ 885 void 886 writeData(uint8_t *p) const 887 { 888 std::memcpy(p, getConstPtr<uint8_t>(), getSize()); 889 } 890 891 /** 892 * Copy data from the packet to the memory at the provided pointer. 893 */ 894 void 895 writeDataToBlock(uint8_t *blk_data, int blkSize) const 896 { 897 writeData(blk_data + getOffset(blkSize)); 898 } 899 900 /** 901 * delete the data pointed to in the data pointer. Ok to call to 902 * matter how data was allocted. 903 */ 904 void 905 deleteData() 906 { 907 if (flags.isSet(DYNAMIC_DATA)) 908 delete [] data; 909 910 flags.clear(STATIC_DATA|DYNAMIC_DATA); 911 data = NULL; 912 } 913 914 /** Allocate memory for the packet. */ 915 void 916 allocate() 917 { 918 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 919 flags.set(DYNAMIC_DATA); 920 data = new uint8_t[getSize()]; 921 } 922 923 /** 924 * Check a functional request against a memory value stored in 925 * another packet (i.e. an in-transit request or 926 * response). Returns true if the current packet is a read, and 927 * the other packet provides the data, which is then copied to the 928 * current packet. If the current packet is a write, and the other 929 * packet intersects this one, then we update the data 930 * accordingly. 931 */ 932 bool 933 checkFunctional(PacketPtr other) 934 { 935 // all packets that are carrying a payload should have a valid 936 // data pointer 937 return checkFunctional(other, other->getAddr(), other->isSecure(), 938 other->getSize(), 939 other->hasData() ? 940 other->getPtr<uint8_t>() : NULL); 941 } 942 943 /** 944 * Is this request notification of a clean or dirty eviction from the cache. 945 **/ 946 bool 947 evictingBlock() const 948 { 949 return (cmd == MemCmd::Writeback || 950 cmd == MemCmd::CleanEvict); 951 } 952 953 /** 954 * Does the request need to check for cached copies of the same block 955 * in the memory hierarchy above. 956 **/ 957 bool 958 mustCheckAbove() const 959 { 960 return (cmd == MemCmd::HardPFReq || 961 evictingBlock()); 962 } 963 964 /** 965 * Check a functional request against a memory value represented 966 * by a base/size pair and an associated data array. If the 967 * current packet is a read, it may be satisfied by the memory 968 * value. If the current packet is a write, it may update the 969 * memory value. 970 */ 971 bool 972 checkFunctional(Printable *obj, Addr base, bool is_secure, int size, 973 uint8_t *_data); 974 975 /** 976 * Push label for PrintReq (safe to call unconditionally). 977 */ 978 void 979 pushLabel(const std::string &lbl) 980 { 981 if (isPrint()) 982 safe_cast<PrintReqState*>(senderState)->pushLabel(lbl); 983 } 984 985 /** 986 * Pop label for PrintReq (safe to call unconditionally). 987 */ 988 void 989 popLabel() 990 { 991 if (isPrint()) 992 safe_cast<PrintReqState*>(senderState)->popLabel(); 993 } 994 995 void print(std::ostream &o, int verbosity = 0, 996 const std::string &prefix = "") const; 997 998 /** 999 * A no-args wrapper of print(std::ostream...) 1000 * meant to be invoked from DPRINTFs 1001 * avoiding string overheads in fast mode 1002 * @return string with the request's type and start<->end addresses 1003 */ 1004 std::string print() const; 1005}; 1006 1007#endif //__MEM_PACKET_HH 1008