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39 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
41 * Authors: Ron Dreslinski
50 * Declaration of the Packet class.
53 #ifndef __MEM_PACKET_HH__
54 #define __MEM_PACKET_HH__
60 #include "base/cast.hh"
61 #include "base/compiler.hh"
62 #include "base/flags.hh"
63 #include "base/logging.hh"
64 #include "base/printable.hh"
65 #include "base/types.hh"
66 #include "mem/request.hh"
67 #include "sim/core.hh"
70 typedef Packet *PacketPtr;
71 typedef uint8_t* PacketDataPtr;
72 typedef std::list<PacketPtr> PacketList;
73 typedef uint64_t PacketId;
81 * List of all commands associated with a packet.
88 ReadRespWithInvalidate,
93 WriteClean, // writes dirty data below without evicting
101 SCUpgradeReq, // Special "weak" upgrade for StoreCond
103 SCUpgradeFailReq, // Failed SCUpgradeReq in MSHR (never sent)
104 UpgradeFailResp, // Valid for SCUpgradeReq only
111 StoreCondFailReq, // Failed StoreCondReq in MSHR (never sent)
124 // @TODO these should be classified as responses rather than
125 // requests; coding them as requests initially for backwards
127 InvalidDestError, // packet dest field invalid
128 BadAddressError, // memory address invalid
129 FunctionalReadError, // unable to fulfill functional read
130 FunctionalWriteError, // unable to fulfill functional write
131 // Fake simulator-only commands
132 PrintReq, // Print state matching address
133 FlushReq, //request for a cache flush
134 InvalidateReq, // request for address to be invalidated
141 * List of command attributes.
145 IsRead, //!< Data flows from responder to requester
146 IsWrite, //!< Data flows from requester to responder
149 IsClean, //!< Cleans any existing dirty blocks
150 NeedsWritable, //!< Requires writable copy to complete in-cache
151 IsRequest, //!< Issued by requester
152 IsResponse, //!< Issue by responder
153 NeedsResponse, //!< Requester needs response from target
157 IsLlsc, //!< Alpha/MIPS LL or SC access
158 HasData, //!< There is an associated payload
159 IsError, //!< Error response
160 IsPrint, //!< Print state matching address (for debugging)
161 IsFlush, //!< Flush the address from caches
162 FromCache, //!< Request originated from a caching agent
163 NUM_COMMAND_ATTRIBUTES
167 * Structure that defines attributes and other data associated
172 /// Set of attribute flags.
173 const std::bitset<NUM_COMMAND_ATTRIBUTES> attributes;
174 /// Corresponding response for requests; InvalidCmd if no
175 /// response is applicable.
176 const Command response;
177 /// String representation (for printing)
178 const std::string str;
181 /// Array to map Command enum to associated info.
182 static const CommandInfo commandInfo[];
189 testCmdAttrib(MemCmd::Attribute attrib) const
191 return commandInfo[cmd].attributes[attrib] != 0;
196 bool isRead() const { return testCmdAttrib(IsRead); }
197 bool isWrite() const { return testCmdAttrib(IsWrite); }
198 bool isUpgrade() const { return testCmdAttrib(IsUpgrade); }
199 bool isRequest() const { return testCmdAttrib(IsRequest); }
200 bool isResponse() const { return testCmdAttrib(IsResponse); }
201 bool needsWritable() const { return testCmdAttrib(NeedsWritable); }
202 bool needsResponse() const { return testCmdAttrib(NeedsResponse); }
203 bool isInvalidate() const { return testCmdAttrib(IsInvalidate); }
204 bool isEviction() const { return testCmdAttrib(IsEviction); }
205 bool isClean() const { return testCmdAttrib(IsClean); }
206 bool fromCache() const { return testCmdAttrib(FromCache); }
209 * A writeback is an eviction that carries data.
211 bool isWriteback() const { return testCmdAttrib(IsEviction) &&
212 testCmdAttrib(HasData); }
215 * Check if this particular packet type carries payload data. Note
216 * that this does not reflect if the data pointer of the packet is
219 bool hasData() const { return testCmdAttrib(HasData); }
220 bool isLLSC() const { return testCmdAttrib(IsLlsc); }
221 bool isSWPrefetch() const { return testCmdAttrib(IsSWPrefetch); }
222 bool isHWPrefetch() const { return testCmdAttrib(IsHWPrefetch); }
223 bool isPrefetch() const { return testCmdAttrib(IsSWPrefetch) ||
224 testCmdAttrib(IsHWPrefetch); }
225 bool isError() const { return testCmdAttrib(IsError); }
226 bool isPrint() const { return testCmdAttrib(IsPrint); }
227 bool isFlush() const { return testCmdAttrib(IsFlush); }
230 responseCommand() const
232 return commandInfo[cmd].response;
235 /// Return the string to a cmd given by idx.
236 const std::string &toString() const { return commandInfo[cmd].str; }
237 int toInt() const { return (int)cmd; }
239 MemCmd(Command _cmd) : cmd(_cmd) { }
240 MemCmd(int _cmd) : cmd((Command)_cmd) { }
241 MemCmd() : cmd(InvalidCmd) { }
243 bool operator==(MemCmd c2) const { return (cmd == c2.cmd); }
244 bool operator!=(MemCmd c2) const { return (cmd != c2.cmd); }
248 * A Packet is used to encapsulate a transfer between two objects in
249 * the memory system (e.g., the L1 and L2 cache). (In contrast, a
250 * single Request travels all the way from the requester to the
251 * ultimate destination and back, possibly being conveyed by several
252 * different Packets along the way.)
254 class Packet : public Printable
257 typedef uint32_t FlagsType;
258 typedef ::Flags<FlagsType> Flags;
263 // Flags to transfer across when copying a packet
264 COPY_FLAGS = 0x0000003F,
266 // Does this packet have sharers (which means it should not be
267 // considered writable) or not. See setHasSharers below.
268 HAS_SHARERS = 0x00000001,
270 // Special control flags
271 /// Special timing-mode atomic snoop for multi-level coherence.
272 EXPRESS_SNOOP = 0x00000002,
274 /// Allow a responding cache to inform the cache hierarchy
275 /// that it had a writable copy before responding. See
276 /// setResponderHadWritable below.
277 RESPONDER_HAD_WRITABLE = 0x00000004,
279 // Snoop co-ordination flag to indicate that a cache is
280 // responding to a snoop. See setCacheResponding below.
281 CACHE_RESPONDING = 0x00000008,
283 // The writeback/writeclean should be propagated further
284 // downstream by the receiver
285 WRITE_THROUGH = 0x00000010,
287 // Response co-ordination flag for cache maintenance
289 SATISFIED = 0x00000020,
291 /// Are the 'addr' and 'size' fields valid?
292 VALID_ADDR = 0x00000100,
293 VALID_SIZE = 0x00000200,
295 /// Is the data pointer set to a value that shouldn't be freed
296 /// when the packet is destroyed?
297 STATIC_DATA = 0x00001000,
298 /// The data pointer points to a value that should be freed when
299 /// the packet is destroyed. The pointer is assumed to be pointing
300 /// to an array, and delete [] is consequently called
301 DYNAMIC_DATA = 0x00002000,
303 /// suppress the error if this packet encounters a functional
305 SUPPRESS_FUNC_ERROR = 0x00008000,
307 // Signal block present to squash prefetch and cache evict packets
308 // through express snoop flag
309 BLOCK_CACHED = 0x00010000
315 typedef MemCmd::Command Command;
317 /// The command field of the packet.
322 /// A pointer to the original request.
327 * A pointer to the data being transferred. It can be different
328 * sizes at each level of the hierarchy so it belongs to the
329 * packet, not request. This may or may not be populated when a
330 * responder receives the packet. If not populated memory should
335 /// The address of the request. This address could be virtual or
336 /// physical, depending on the system configuration.
339 /// True if the request targets the secure memory space.
342 /// The size of the request or transfer.
346 * Track the bytes found that satisfy a functional read.
348 std::vector<bool> bytesValid;
350 // Quality of Service priority value
356 * The extra delay from seeing the packet until the header is
357 * transmitted. This delay is used to communicate the crossbar
358 * forwarding latency to the neighbouring object (e.g. a cache)
359 * that actually makes the packet wait. As the delay is relative,
360 * a 32-bit unsigned should be sufficient.
362 uint32_t headerDelay;
365 * Keep track of the extra delay incurred by snooping upwards
366 * before sending a request down the memory system. This is used
367 * by the coherent crossbar to account for the additional request
373 * The extra pipelining delay from seeing the packet until the end of
374 * payload is transmitted by the component that provided it (if
375 * any). This includes the header delay. Similar to the header
376 * delay, this is used to make up for the fact that the
377 * crossbar does not make the packet wait. As the delay is
378 * relative, a 32-bit unsigned should be sufficient.
380 uint32_t payloadDelay;
383 * A virtual base opaque structure used to hold state associated
384 * with the packet (e.g., an MSHR), specific to a MemObject that
385 * sees the packet. A pointer to this state is returned in the
386 * packet's response so that the MemObject in question can quickly
387 * look up the state needed to process it. A specific subclass
388 * would be derived from this to carry state specific to a
389 * particular sending device.
391 * As multiple MemObjects may add their SenderState throughout the
392 * memory system, the SenderStates create a stack, where a
393 * MemObject can add a new Senderstate, as long as the
394 * predecessing SenderState is restored when the response comes
395 * back. For this reason, the predecessor should always be
396 * populated with the current SenderState of a packet before
397 * modifying the senderState field in the request packet.
401 SenderState* predecessor;
402 SenderState() : predecessor(NULL) {}
403 virtual ~SenderState() {}
407 * Object used to maintain state of a PrintReq. The senderState
408 * field of a PrintReq should always be of this type.
410 class PrintReqState : public SenderState
414 * An entry in the label stack.
416 struct LabelStackEntry
418 const std::string label;
421 LabelStackEntry(const std::string &_label, std::string *_prefix);
424 typedef std::list<LabelStackEntry> LabelStack;
425 LabelStack labelStack;
427 std::string *curPrefixPtr;
433 PrintReqState(std::ostream &os, int verbosity = 0);
437 * Returns the current line prefix.
439 const std::string &curPrefix() { return *curPrefixPtr; }
442 * Push a label onto the label stack, and prepend the given
443 * prefix string onto the current prefix. Labels will only be
444 * printed if an object within the label's scope is printed.
446 void pushLabel(const std::string &lbl,
447 const std::string &prefix = " ");
450 * Pop a label off the label stack.
455 * Print all of the pending unprinted labels on the
456 * stack. Called by printObj(), so normally not called by
457 * users unless bypassing printObj().
462 * Print a Printable object to os, because it matched the
463 * address on a PrintReq.
465 void printObj(Printable *obj);
469 * This packet's sender state. Devices should use dynamic_cast<>
470 * to cast to the state appropriate to the sender. The intent of
471 * this variable is to allow a device to attach extra information
472 * to a request. A response packet must return the sender state
473 * that was attached to the original request (even if a new packet
476 SenderState *senderState;
479 * Push a new sender state to the packet and make the current
480 * sender state the predecessor of the new one. This should be
481 * prefered over direct manipulation of the senderState member
484 * @param sender_state SenderState to push at the top of the stack
486 void pushSenderState(SenderState *sender_state);
489 * Pop the top of the state stack and return a pointer to it. This
490 * assumes the current sender state is not NULL. This should be
491 * preferred over direct manipulation of the senderState member
494 * @return The current top of the stack
496 SenderState *popSenderState();
499 * Go through the sender state stack and return the first instance
500 * that is of type T (as determined by a dynamic_cast). If there
501 * is no sender state of type T, NULL is returned.
503 * @return The topmost state of type T
505 template <typename T>
506 T * findNextSenderState() const
509 SenderState* sender_state = senderState;
510 while (t == NULL && sender_state != NULL) {
511 t = dynamic_cast<T*>(sender_state);
512 sender_state = sender_state->predecessor;
517 /// Return the string name of the cmd field (for debugging and
519 const std::string &cmdString() const { return cmd.toString(); }
521 /// Return the index of this command.
522 inline int cmdToIndex() const { return cmd.toInt(); }
524 bool isRead() const { return cmd.isRead(); }
525 bool isWrite() const { return cmd.isWrite(); }
526 bool isUpgrade() const { return cmd.isUpgrade(); }
527 bool isRequest() const { return cmd.isRequest(); }
528 bool isResponse() const { return cmd.isResponse(); }
529 bool needsWritable() const
531 // we should never check if a response needsWritable, the
532 // request has this flag, and for a response we should rather
533 // look at the hasSharers flag (if not set, the response is to
534 // be considered writable)
536 return cmd.needsWritable();
538 bool needsResponse() const { return cmd.needsResponse(); }
539 bool isInvalidate() const { return cmd.isInvalidate(); }
540 bool isEviction() const { return cmd.isEviction(); }
541 bool isClean() const { return cmd.isClean(); }
542 bool fromCache() const { return cmd.fromCache(); }
543 bool isWriteback() const { return cmd.isWriteback(); }
544 bool hasData() const { return cmd.hasData(); }
545 bool hasRespData() const
547 MemCmd resp_cmd = cmd.responseCommand();
548 return resp_cmd.hasData();
550 bool isLLSC() const { return cmd.isLLSC(); }
551 bool isError() const { return cmd.isError(); }
552 bool isPrint() const { return cmd.isPrint(); }
553 bool isFlush() const { return cmd.isFlush(); }
558 * Set the cacheResponding flag. This is used by the caches to
559 * signal another cache that they are responding to a request. A
560 * cache will only respond to snoops if it has the line in either
561 * Modified or Owned state. Note that on snoop hits we always pass
562 * the line as Modified and never Owned. In the case of an Owned
563 * line we proceed to invalidate all other copies.
565 * On a cache fill (see Cache::handleFill), we check hasSharers
566 * first, ignoring the cacheResponding flag if hasSharers is set.
567 * A line is consequently allocated as:
569 * hasSharers cacheResponding state
572 * false false Exclusive
573 * false true Modified
575 void setCacheResponding()
578 assert(!flags.isSet(CACHE_RESPONDING));
579 flags.set(CACHE_RESPONDING);
581 bool cacheResponding() const { return flags.isSet(CACHE_RESPONDING); }
583 * On fills, the hasSharers flag is used by the caches in
584 * combination with the cacheResponding flag, as clarified
585 * above. If the hasSharers flag is not set, the packet is passing
586 * writable. Thus, a response from a memory passes the line as
587 * writable by default.
589 * The hasSharers flag is also used by upstream caches to inform a
590 * downstream cache that they have the block (by calling
591 * setHasSharers on snoop request packets that hit in upstream
592 * cachs tags or MSHRs). If the snoop packet has sharers, a
593 * downstream cache is prevented from passing a dirty line upwards
594 * if it was not explicitly asked for a writable copy. See
595 * Cache::satisfyCpuSideRequest.
597 * The hasSharers flag is also used on writebacks, in
598 * combination with the WritbackClean or WritebackDirty commands,
599 * to allocate the block downstream either as:
601 * command hasSharers state
602 * WritebackDirty false Modified
603 * WritebackDirty true Owned
604 * WritebackClean false Exclusive
605 * WritebackClean true Shared
607 void setHasSharers() { flags.set(HAS_SHARERS); }
608 bool hasSharers() const { return flags.isSet(HAS_SHARERS); }
612 * The express snoop flag is used for two purposes. Firstly, it is
613 * used to bypass flow control for normal (non-snoop) requests
614 * going downstream in the memory system. In cases where a cache
615 * is responding to a snoop from another cache (it had a dirty
616 * line), but the line is not writable (and there are possibly
617 * other copies), the express snoop flag is set by the downstream
618 * cache to invalidate all other copies in zero time. Secondly,
619 * the express snoop flag is also set to be able to distinguish
620 * snoop packets that came from a downstream cache, rather than
621 * snoop packets from neighbouring caches.
623 void setExpressSnoop() { flags.set(EXPRESS_SNOOP); }
624 bool isExpressSnoop() const { return flags.isSet(EXPRESS_SNOOP); }
627 * On responding to a snoop request (which only happens for
628 * Modified or Owned lines), make sure that we can transform an
629 * Owned response to a Modified one. If this flag is not set, the
630 * responding cache had the line in the Owned state, and there are
631 * possibly other Shared copies in the memory system. A downstream
632 * cache helps in orchestrating the invalidation of these copies
633 * by sending out the appropriate express snoops.
635 void setResponderHadWritable()
637 assert(cacheResponding());
638 assert(!responderHadWritable());
639 flags.set(RESPONDER_HAD_WRITABLE);
641 bool responderHadWritable() const
642 { return flags.isSet(RESPONDER_HAD_WRITABLE); }
645 * A writeback/writeclean cmd gets propagated further downstream
646 * by the receiver when the flag is set.
648 void setWriteThrough()
650 assert(cmd.isWrite() &&
651 (cmd.isEviction() || cmd == MemCmd::WriteClean));
652 flags.set(WRITE_THROUGH);
654 void clearWriteThrough() { flags.clear(WRITE_THROUGH); }
655 bool writeThrough() const { return flags.isSet(WRITE_THROUGH); }
658 * Set when a request hits in a cache and the cache is not going
659 * to respond. This is used by the crossbar to coordinate
660 * responses for cache maintenance operations.
664 assert(cmd.isClean());
665 assert(!flags.isSet(SATISFIED));
666 flags.set(SATISFIED);
668 bool satisfied() const { return flags.isSet(SATISFIED); }
670 void setSuppressFuncError() { flags.set(SUPPRESS_FUNC_ERROR); }
671 bool suppressFuncError() const { return flags.isSet(SUPPRESS_FUNC_ERROR); }
672 void setBlockCached() { flags.set(BLOCK_CACHED); }
673 bool isBlockCached() const { return flags.isSet(BLOCK_CACHED); }
674 void clearBlockCached() { flags.clear(BLOCK_CACHED); }
678 * Returns 0 if QoS value was never set (constructor default).
680 * @return QoS priority value of the packet
682 inline uint8_t qosValue() const { return _qosValue; }
686 * Interface for setting QoS priority value of the packet.
688 * @param qos_value QoS priority value
690 inline void qosValue(const uint8_t qos_value)
691 { _qosValue = qos_value; }
693 inline MasterID masterId() const { return req->masterId(); }
695 // Network error conditions... encapsulate them as methods since
696 // their encoding keeps changing (from result field to command
701 assert(isResponse());
702 cmd = MemCmd::BadAddressError;
705 void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; }
707 Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; }
709 * Update the address of this packet mid-transaction. This is used
710 * by the address mapper to change an already set address to a new
711 * one based on the system configuration. It is intended to remap
712 * an existing address, so it asserts that the current address is
715 void setAddr(Addr _addr) { assert(flags.isSet(VALID_ADDR)); addr = _addr; }
717 unsigned getSize() const { assert(flags.isSet(VALID_SIZE)); return size; }
719 Addr getOffset(unsigned int blk_size) const
721 return getAddr() & Addr(blk_size - 1);
724 Addr getBlockAddr(unsigned int blk_size) const
726 return getAddr() & ~(Addr(blk_size - 1));
729 bool isSecure() const
731 assert(flags.isSet(VALID_ADDR));
736 * Accessor function to atomic op.
738 AtomicOpFunctor *getAtomicOp() const { return req->getAtomicOpFunctor(); }
739 bool isAtomicOp() const { return req->isAtomic(); }
742 * It has been determined that the SC packet should successfully update
743 * memory. Therefore, convert this SC packet to a normal write.
750 cmd = MemCmd::WriteReq;
754 * When ruby is in use, Ruby will monitor the cache line and the
755 * phys memory should treat LL ops as normal reads.
762 cmd = MemCmd::ReadReq;
766 * Constructor. Note that a Request object must be constructed
767 * first, but the Requests's physical address and size fields need
768 * not be valid. The command must be supplied.
770 Packet(const RequestPtr &_req, MemCmd _cmd)
771 : cmd(_cmd), id((PacketId)_req.get()), req(_req),
772 data(nullptr), addr(0), _isSecure(false), size(0),
773 _qosValue(0), headerDelay(0), snoopDelay(0),
774 payloadDelay(0), senderState(NULL)
776 if (req->hasPaddr()) {
777 addr = req->getPaddr();
778 flags.set(VALID_ADDR);
779 _isSecure = req->isSecure();
781 if (req->hasSize()) {
782 size = req->getSize();
783 flags.set(VALID_SIZE);
788 * Alternate constructor if you are trying to create a packet with
789 * a request that is for a whole block, not the address from the
790 * req. this allows for overriding the size/addr of the req.
792 Packet(const RequestPtr &_req, MemCmd _cmd, int _blkSize, PacketId _id = 0)
793 : cmd(_cmd), id(_id ? _id : (PacketId)_req.get()), req(_req),
794 data(nullptr), addr(0), _isSecure(false),
795 _qosValue(0), headerDelay(0),
796 snoopDelay(0), payloadDelay(0), senderState(NULL)
798 if (req->hasPaddr()) {
799 addr = req->getPaddr() & ~(_blkSize - 1);
800 flags.set(VALID_ADDR);
801 _isSecure = req->isSecure();
804 flags.set(VALID_SIZE);
808 * Alternate constructor for copying a packet. Copy all fields
809 * *except* if the original packet's data was dynamic, don't copy
810 * that, as we can't guarantee that the new packet's lifetime is
811 * less than that of the original packet. In this case the new
812 * packet should allocate its own data.
814 Packet(const PacketPtr pkt, bool clear_flags, bool alloc_data)
815 : cmd(pkt->cmd), id(pkt->id), req(pkt->req),
817 addr(pkt->addr), _isSecure(pkt->_isSecure), size(pkt->size),
818 bytesValid(pkt->bytesValid),
819 _qosValue(pkt->qosValue()),
820 headerDelay(pkt->headerDelay),
822 payloadDelay(pkt->payloadDelay),
823 senderState(pkt->senderState)
826 flags.set(pkt->flags & COPY_FLAGS);
828 flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE));
830 // should we allocate space for data, or not, the express
831 // snoops do not need to carry any data as they only serve to
832 // co-ordinate state changes
834 // even if asked to allocate data, if the original packet
835 // holds static data, then the sender will not be doing
836 // any memcpy on receiving the response, thus we simply
837 // carry the pointer forward
838 if (pkt->flags.isSet(STATIC_DATA)) {
840 flags.set(STATIC_DATA);
848 * Generate the appropriate read MemCmd based on the Request flags.
851 makeReadCmd(const RequestPtr &req)
854 return MemCmd::LoadLockedReq;
855 else if (req->isPrefetch())
856 return MemCmd::SoftPFReq;
858 return MemCmd::ReadReq;
862 * Generate the appropriate write MemCmd based on the Request flags.
865 makeWriteCmd(const RequestPtr &req)
868 return MemCmd::StoreCondReq;
869 else if (req->isSwap() || req->isAtomic())
870 return MemCmd::SwapReq;
871 else if (req->isCacheInvalidate()) {
872 return req->isCacheClean() ? MemCmd::CleanInvalidReq :
873 MemCmd::InvalidateReq;
874 } else if (req->isCacheClean()) {
875 return MemCmd::CleanSharedReq;
877 return MemCmd::WriteReq;
881 * Constructor-like methods that return Packets based on Request objects.
882 * Fine-tune the MemCmd type if it's not a vanilla read or write.
885 createRead(const RequestPtr &req)
887 return new Packet(req, makeReadCmd(req));
891 createWrite(const RequestPtr &req)
893 return new Packet(req, makeWriteCmd(req));
897 * clean up packet variables
905 * Take a request packet and modify it in place to be suitable for
906 * returning as a response to that request.
911 assert(needsResponse());
913 cmd = cmd.responseCommand();
915 // responses are never express, even if the snoop that
916 // triggered them was
917 flags.clear(EXPRESS_SNOOP);
933 setFunctionalResponseStatus(bool success)
937 cmd = MemCmd::FunctionalWriteError;
939 cmd = MemCmd::FunctionalReadError;
945 setSize(unsigned size)
947 assert(!flags.isSet(VALID_SIZE));
950 flags.set(VALID_SIZE);
957 * @name Data accessor mehtods
961 * Set the data pointer to the following value that should not be
962 * freed. Static data allows us to do a single memcpy even if
963 * multiple packets are required to get from source to destination
964 * and back. In essence the pointer is set calling dataStatic on
965 * the original packet, and whenever this packet is copied and
966 * forwarded the same pointer is passed on. When a packet
967 * eventually reaches the destination holding the data, it is
968 * copied once into the location originally set. On the way back
969 * to the source, no copies are necessary.
971 template <typename T>
975 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
976 data = (PacketDataPtr)p;
977 flags.set(STATIC_DATA);
981 * Set the data pointer to the following value that should not be
982 * freed. This version of the function allows the pointer passed
983 * to us to be const. To avoid issues down the line we cast the
984 * constness away, the alternative would be to keep both a const
985 * and non-const data pointer and cleverly choose between
986 * them. Note that this is only allowed for static data.
988 template <typename T>
990 dataStaticConst(const T *p)
992 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
993 data = const_cast<PacketDataPtr>(p);
994 flags.set(STATIC_DATA);
998 * Set the data pointer to a value that should have delete []
999 * called on it. Dynamic data is local to this packet, and as the
1000 * packet travels from source to destination, forwarded packets
1001 * will allocate their own data. When a packet reaches the final
1002 * destination it will populate the dynamic data of that specific
1003 * packet, and on the way back towards the source, memcpy will be
1004 * invoked in every step where a new packet was created e.g. in
1005 * the caches. Ultimately when the response reaches the source a
1006 * final memcpy is needed to extract the data from the packet
1007 * before it is deallocated.
1009 template <typename T>
1013 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
1014 data = (PacketDataPtr)p;
1015 flags.set(DYNAMIC_DATA);
1019 * get a pointer to the data ptr.
1021 template <typename T>
1025 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
1029 template <typename T>
1033 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
1034 return (const T*)data;
1038 * Get the data in the packet byte swapped from big endian to
1041 template <typename T>
1045 * Get the data in the packet byte swapped from little endian to
1048 template <typename T>
1052 * Get the data in the packet byte swapped from the specified
1055 template <typename T>
1056 T get(ByteOrder endian) const;
1059 * Get the data in the packet byte swapped from guest to host
1062 template <typename T>
1065 /** Set the value in the data pointer to v as big endian. */
1066 template <typename T>
1069 /** Set the value in the data pointer to v as little endian. */
1070 template <typename T>
1074 * Set the value in the data pointer to v using the specified
1077 template <typename T>
1078 void set(T v, ByteOrder endian);
1080 #if THE_ISA != NULL_ISA
1081 /** Set the value in the data pointer to v as guest endian. */
1082 template <typename T>
1088 * Get the data in the packet byte swapped from the specified
1089 * endianness and zero-extended to 64 bits.
1091 uint64_t getUintX(ByteOrder endian) const;
1094 * Set the value in the word w after truncating it to the length
1095 * of the packet and then byteswapping it to the desired
1098 void setUintX(uint64_t w, ByteOrder endian);
1101 * Copy data into the packet from the provided pointer.
1104 setData(const uint8_t *p)
1106 // we should never be copying data onto itself, which means we
1107 // must idenfity packets with static data, as they carry the
1108 // same pointer from source to destination and back
1109 assert(p != getPtr<uint8_t>() || flags.isSet(STATIC_DATA));
1111 if (p != getPtr<uint8_t>())
1112 // for packet with allocated dynamic data, we copy data from
1113 // one to the other, e.g. a forwarded response to a response
1114 std::memcpy(getPtr<uint8_t>(), p, getSize());
1118 * Copy data into the packet from the provided block pointer,
1119 * which is aligned to the given block size.
1122 setDataFromBlock(const uint8_t *blk_data, int blkSize)
1124 setData(blk_data + getOffset(blkSize));
1128 * Copy data from the packet to the memory at the provided pointer.
1129 * @param p Pointer to which data will be copied.
1132 writeData(uint8_t *p) const
1134 std::memcpy(p, getConstPtr<uint8_t>(), getSize());
1138 * Copy data from the packet to the provided block pointer, which
1139 * is aligned to the given block size.
1140 * @param blk_data Pointer to block to which data will be copied.
1141 * @param blkSize Block size in bytes.
1144 writeDataToBlock(uint8_t *blk_data, int blkSize) const
1146 writeData(blk_data + getOffset(blkSize));
1150 * delete the data pointed to in the data pointer. Ok to call to
1151 * matter how data was allocted.
1156 if (flags.isSet(DYNAMIC_DATA))
1159 flags.clear(STATIC_DATA|DYNAMIC_DATA);
1163 /** Allocate memory for the packet. */
1167 // if either this command or the response command has a data
1168 // payload, actually allocate space
1169 if (hasData() || hasRespData()) {
1170 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
1171 flags.set(DYNAMIC_DATA);
1172 data = new uint8_t[getSize()];
1178 /** Get the data in the packet without byte swapping. */
1179 template <typename T>
1182 /** Set the value in the data pointer to v without byte swapping. */
1183 template <typename T>
1188 * Check a functional request against a memory value stored in
1189 * another packet (i.e. an in-transit request or
1190 * response). Returns true if the current packet is a read, and
1191 * the other packet provides the data, which is then copied to the
1192 * current packet. If the current packet is a write, and the other
1193 * packet intersects this one, then we update the data
1197 trySatisfyFunctional(PacketPtr other)
1199 // all packets that are carrying a payload should have a valid
1201 return trySatisfyFunctional(other, other->getAddr(), other->isSecure(),
1204 other->getPtr<uint8_t>() : NULL);
1208 * Does the request need to check for cached copies of the same block
1209 * in the memory hierarchy above.
1212 mustCheckAbove() const
1214 return cmd == MemCmd::HardPFReq || isEviction();
1218 * Is this packet a clean eviction, including both actual clean
1219 * evict packets, but also clean writebacks.
1222 isCleanEviction() const
1224 return cmd == MemCmd::CleanEvict || cmd == MemCmd::WritebackClean;
1228 * Check a functional request against a memory value represented
1229 * by a base/size pair and an associated data array. If the
1230 * current packet is a read, it may be satisfied by the memory
1231 * value. If the current packet is a write, it may update the
1235 trySatisfyFunctional(Printable *obj, Addr base, bool is_secure, int size,
1239 * Push label for PrintReq (safe to call unconditionally).
1242 pushLabel(const std::string &lbl)
1245 safe_cast<PrintReqState*>(senderState)->pushLabel(lbl);
1249 * Pop label for PrintReq (safe to call unconditionally).
1255 safe_cast<PrintReqState*>(senderState)->popLabel();
1258 void print(std::ostream &o, int verbosity = 0,
1259 const std::string &prefix = "") const;
1262 * A no-args wrapper of print(std::ostream...)
1263 * meant to be invoked from DPRINTFs
1264 * avoiding string overheads in fast mode
1265 * @return string with the request's type and start<->end addresses
1267 std::string print() const;
1270 #endif //__MEM_PACKET_HH