#include <cassert>
#include <list>
+#include <bitset>
+#include "base/compiler.hh"
+#include "base/fast_alloc.hh"
+#include "base/misc.hh"
+#include "base/printable.hh"
#include "mem/request.hh"
#include "sim/host.hh"
-#include "sim/root.hh"
+#include "sim/core.hh"
+
struct Packet;
typedef Packet *PacketPtr;
typedef uint8_t* PacketDataPtr;
typedef std::list<PacketPtr> PacketList;
-//Coherence Flags
-#define NACKED_LINE (1 << 0)
-#define SATISFIED (1 << 1)
-#define SHARED_LINE (1 << 2)
-#define CACHE_LINE_FILL (1 << 3)
-#define COMPRESSED (1 << 4)
-#define NO_ALLOCATE (1 << 5)
-#define SNOOP_COMMIT (1 << 6)
-
-//for now. @todo fix later
-#define NUM_MEM_CMDS (1 << 11)
+class MemCmd
+{
+ public:
+
+ /** List of all commands associated with a packet. */
+ enum Command
+ {
+ InvalidCmd,
+ ReadReq,
+ ReadResp,
+ ReadRespWithInvalidate,
+ WriteReq,
+ WriteResp,
+ Writeback,
+ SoftPFReq,
+ HardPFReq,
+ SoftPFResp,
+ HardPFResp,
+ WriteInvalidateReq,
+ WriteInvalidateResp,
+ UpgradeReq,
+ UpgradeResp,
+ ReadExReq,
+ ReadExResp,
+ LoadLockedReq,
+ LoadLockedResp,
+ StoreCondReq,
+ StoreCondResp,
+ SwapReq,
+ SwapResp,
+ // Error responses
+ // @TODO these should be classified as responses rather than
+ // requests; coding them as requests initially for backwards
+ // compatibility
+ NetworkNackError, // nacked at network layer (not by protocol)
+ InvalidDestError, // packet dest field invalid
+ BadAddressError, // memory address invalid
+ // Fake simulator-only commands
+ PrintReq, // Print state matching address
+ NUM_MEM_CMDS
+ };
+
+ private:
+ /** List of command attributes. */
+ enum Attribute
+ {
+ IsRead, //!< Data flows from responder to requester
+ IsWrite, //!< Data flows from requester to responder
+ IsPrefetch, //!< Not a demand access
+ IsInvalidate,
+ NeedsExclusive, //!< Requires exclusive copy to complete in-cache
+ IsRequest, //!< Issued by requester
+ IsResponse, //!< Issue by responder
+ NeedsResponse, //!< Requester needs response from target
+ IsSWPrefetch,
+ IsHWPrefetch,
+ IsLocked, //!< Alpha/MIPS LL or SC access
+ HasData, //!< There is an associated payload
+ IsError, //!< Error response
+ IsPrint, //!< Print state matching address (for debugging)
+ NUM_COMMAND_ATTRIBUTES
+ };
+
+ /** Structure that defines attributes and other data associated
+ * with a Command. */
+ struct CommandInfo {
+ /** Set of attribute flags. */
+ const std::bitset<NUM_COMMAND_ATTRIBUTES> attributes;
+ /** Corresponding response for requests; InvalidCmd if no
+ * response is applicable. */
+ const Command response;
+ /** String representation (for printing) */
+ const std::string str;
+ };
+
+ /** Array to map Command enum to associated info. */
+ static const CommandInfo commandInfo[];
+
+ private:
+
+ Command cmd;
+
+ bool testCmdAttrib(MemCmd::Attribute attrib) const {
+ return commandInfo[cmd].attributes[attrib] != 0;
+ }
+
+ public:
+
+ bool isRead() const { return testCmdAttrib(IsRead); }
+ bool isWrite() const { return testCmdAttrib(IsWrite); }
+ bool isRequest() const { return testCmdAttrib(IsRequest); }
+ bool isResponse() const { return testCmdAttrib(IsResponse); }
+ bool needsExclusive() const { return testCmdAttrib(NeedsExclusive); }
+ bool needsResponse() const { return testCmdAttrib(NeedsResponse); }
+ bool isInvalidate() const { return testCmdAttrib(IsInvalidate); }
+ bool hasData() const { return testCmdAttrib(HasData); }
+ bool isReadWrite() const { return isRead() && isWrite(); }
+ bool isLocked() const { return testCmdAttrib(IsLocked); }
+ bool isError() const { return testCmdAttrib(IsError); }
+ bool isPrint() const { return testCmdAttrib(IsPrint); }
+
+ const Command responseCommand() const {
+ return commandInfo[cmd].response;
+ }
+
+ /** Return the string to a cmd given by idx. */
+ const std::string &toString() const {
+ return commandInfo[cmd].str;
+ }
+
+ int toInt() const { return (int)cmd; }
+
+ MemCmd(Command _cmd)
+ : cmd(_cmd)
+ { }
+
+ MemCmd(int _cmd)
+ : cmd((Command)_cmd)
+ { }
+
+ MemCmd()
+ : cmd(InvalidCmd)
+ { }
+
+ bool operator==(MemCmd c2) { return (cmd == c2.cmd); }
+ bool operator!=(MemCmd c2) { return (cmd != c2.cmd); }
+
+ friend class Packet;
+};
+
/**
* A Packet is used to encapsulate a transfer between two objects in
* the memory system (e.g., the L1 and L2 cache). (In contrast, a
* ultimate destination and back, possibly being conveyed by several
* different Packets along the way.)
*/
-class Packet
+class Packet : public FastAlloc, public Printable
{
public:
- /** Temporary FLAGS field until cache gets working, this should be in coherence/sender state. */
- uint64_t flags;
+
+ typedef MemCmd::Command Command;
+
+ /** The command field of the packet. */
+ MemCmd cmd;
+
+ /** A pointer to the original request. */
+ RequestPtr req;
private:
/** A pointer to the data being transfered. It can be differnt
* (unlike * addr, size, and src). */
short dest;
+ /** The original value of the command field. Only valid when the
+ * current command field is an error condition; in that case, the
+ * previous contents of the command field are copied here. This
+ * field is *not* set on non-error responses.
+ */
+ MemCmd origCmd;
+
/** Are the 'addr' and 'size' fields valid? */
bool addrSizeValid;
/** Is the 'src' field valid? */
bool srcValid;
+ bool destValid;
+
+ enum Flag {
+ // Snoop response flags
+ MemInhibit,
+ Shared,
+ // Special control flags
+ /// Special timing-mode atomic snoop for multi-level coherence.
+ ExpressSnoop,
+ /// Does supplier have exclusive copy?
+ /// Useful for multi-level coherence.
+ SupplyExclusive,
+ NUM_PACKET_FLAGS
+ };
+ /** Status flags */
+ std::bitset<NUM_PACKET_FLAGS> flags;
public:
* should be routed based on its address. */
static const short Broadcast = -1;
- /** A pointer to the original request. */
- RequestPtr req;
-
- /** A virtual base opaque structure used to hold coherence-related
- * state. A specific subclass would be derived from this to
- * carry state specific to a particular coherence protocol. */
- class CoherenceState {
- public:
- virtual ~CoherenceState() {}
- };
-
- /** This packet's coherence state. Caches should use
- * dynamic_cast<> to cast to the state appropriate for the
- * system's coherence protocol. */
- CoherenceState *coherence;
-
/** A virtual base opaque structure used to hold state associated
* with the packet but specific to the sending device (e.g., an
* MSHR). A pointer to this state is returned in the packet's
* needed to process it. A specific subclass would be derived
* from this to carry state specific to a particular sending
* device. */
- class SenderState {
+ class SenderState : public FastAlloc {
public:
virtual ~SenderState() {}
};
- /** This packet's sender state. Devices should use dynamic_cast<>
- * to cast to the state appropriate to the sender. */
- SenderState *senderState;
+ /**
+ * Object used to maintain state of a PrintReq. The senderState
+ * field of a PrintReq should always be of this type.
+ */
+ class PrintReqState : public SenderState {
+ /** An entry in the label stack. */
+ class LabelStackEntry {
+ public:
+ const std::string label;
+ std::string *prefix;
+ bool labelPrinted;
+ LabelStackEntry(const std::string &_label,
+ std::string *_prefix);
+ };
+
+ typedef std::list<LabelStackEntry> LabelStack;
+ LabelStack labelStack;
+
+ std::string *curPrefixPtr;
- private:
- /** List of command attributes. */
- // If you add a new CommandAttribute, make sure to increase NUM_MEM_CMDS
- // as well.
- enum CommandAttribute
- {
- IsRead = 1 << 0,
- IsWrite = 1 << 1,
- IsPrefetch = 1 << 2,
- IsInvalidate = 1 << 3,
- IsRequest = 1 << 4,
- IsResponse = 1 << 5,
- NeedsResponse = 1 << 6,
- IsSWPrefetch = 1 << 7,
- IsHWPrefetch = 1 << 8,
- IsUpgrade = 1 << 9,
- HasData = 1 << 10
+ public:
+ std::ostream &os;
+ const int verbosity;
+
+ PrintReqState(std::ostream &os, int verbosity = 0);
+ ~PrintReqState();
+
+ /** Returns the current line prefix. */
+ const std::string &curPrefix() { return *curPrefixPtr; }
+
+ /** Push a label onto the label stack, and prepend the given
+ * prefix string onto the current prefix. Labels will only be
+ * printed if an object within the label's scope is
+ * printed. */
+ void pushLabel(const std::string &lbl,
+ const std::string &prefix = " ");
+ /** Pop a label off the label stack. */
+ void popLabel();
+ /** Print all of the pending unprinted labels on the
+ * stack. Called by printObj(), so normally not called by
+ * users unless bypassing printObj(). */
+ void printLabels();
+ /** Print a Printable object to os, because it matched the
+ * address on a PrintReq. */
+ void printObj(Printable *obj);
};
- public:
- /** List of all commands associated with a packet. */
- enum Command
- {
- InvalidCmd = 0,
- ReadReq = IsRead | IsRequest | NeedsResponse,
- WriteReq = IsWrite | IsRequest | NeedsResponse | HasData,
- WriteReqNoAck = IsWrite | IsRequest | HasData,
- ReadResp = IsRead | IsResponse | NeedsResponse | HasData,
- WriteResp = IsWrite | IsResponse | NeedsResponse,
- Writeback = IsWrite | IsRequest | HasData,
- SoftPFReq = IsRead | IsRequest | IsSWPrefetch | NeedsResponse,
- HardPFReq = IsRead | IsRequest | IsHWPrefetch | NeedsResponse,
- SoftPFResp = IsRead | IsResponse | IsSWPrefetch
- | NeedsResponse | HasData,
- HardPFResp = IsRead | IsResponse | IsHWPrefetch
- | NeedsResponse | HasData,
- InvalidateReq = IsInvalidate | IsRequest,
- WriteInvalidateReq = IsWrite | IsInvalidate | IsRequest
- | HasData | NeedsResponse,
- WriteInvalidateResp = IsWrite | IsInvalidate | IsRequest
- | NeedsResponse | IsResponse,
- UpgradeReq = IsInvalidate | IsRequest | IsUpgrade,
- ReadExReq = IsRead | IsInvalidate | IsRequest | NeedsResponse,
- ReadExResp = IsRead | IsInvalidate | IsResponse
- | NeedsResponse | HasData
- };
+ /** This packet's sender state. Devices should use dynamic_cast<>
+ * to cast to the state appropriate to the sender. */
+ SenderState *senderState;
/** Return the string name of the cmd field (for debugging and
* tracing). */
- const std::string &cmdString() const;
-
- /** Reutrn the string to a cmd given by idx. */
- const std::string &cmdIdxToString(Command idx);
+ const std::string &cmdString() const { return cmd.toString(); }
/** Return the index of this command. */
- inline int cmdToIndex() const { return (int) cmd; }
-
- /** The command field of the packet. */
- Command cmd;
-
- bool isRead() const { return (cmd & IsRead) != 0; }
- bool isWrite() const { return (cmd & IsWrite) != 0; }
- bool isRequest() const { return (cmd & IsRequest) != 0; }
- bool isResponse() const { return (cmd & IsResponse) != 0; }
- bool needsResponse() const { return (cmd & NeedsResponse) != 0; }
- bool isInvalidate() const { return (cmd & IsInvalidate) != 0; }
- bool hasData() const { return (cmd & HasData) != 0; }
-
- bool isCacheFill() const { return (flags & CACHE_LINE_FILL) != 0; }
- bool isNoAllocate() const { return (flags & NO_ALLOCATE) != 0; }
- bool isCompressed() const { return (flags & COMPRESSED) != 0; }
-
- bool nic_pkt() { assert("Unimplemented\n" && 0); return false; }
-
- /** Possible results of a packet's request. */
- enum Result
- {
- Success,
- BadAddress,
- Nacked,
- Unknown
- };
-
- /** The result of this packet's request. */
- Result result;
+ inline int cmdToIndex() const { return cmd.toInt(); }
+
+ bool isRead() const { return cmd.isRead(); }
+ bool isWrite() const { return cmd.isWrite(); }
+ bool isRequest() const { return cmd.isRequest(); }
+ bool isResponse() const { return cmd.isResponse(); }
+ bool needsExclusive() const { return cmd.needsExclusive(); }
+ bool needsResponse() const { return cmd.needsResponse(); }
+ bool isInvalidate() const { return cmd.isInvalidate(); }
+ bool hasData() const { return cmd.hasData(); }
+ bool isReadWrite() const { return cmd.isReadWrite(); }
+ bool isLocked() const { return cmd.isLocked(); }
+ bool isError() const { return cmd.isError(); }
+ bool isPrint() const { return cmd.isPrint(); }
+
+ // Snoop flags
+ void assertMemInhibit() { flags[MemInhibit] = true; }
+ bool memInhibitAsserted() { return flags[MemInhibit]; }
+ void assertShared() { flags[Shared] = true; }
+ bool sharedAsserted() { return flags[Shared]; }
+
+ // Special control flags
+ void setExpressSnoop() { flags[ExpressSnoop] = true; }
+ bool isExpressSnoop() { return flags[ExpressSnoop]; }
+ void setSupplyExclusive() { flags[SupplyExclusive] = true; }
+ bool isSupplyExclusive() { return flags[SupplyExclusive]; }
+
+ // Network error conditions... encapsulate them as methods since
+ // their encoding keeps changing (from result field to command
+ // field, etc.)
+ void setNacked() { assert(isResponse()); cmd = MemCmd::NetworkNackError; }
+ void setBadAddress() { assert(isResponse()); cmd = MemCmd::BadAddressError; }
+ bool wasNacked() { return cmd == MemCmd::NetworkNackError; }
+ bool hadBadAddress() { return cmd == MemCmd::BadAddressError; }
+ void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; }
+
+ bool nic_pkt() { panic("Unimplemented"); M5_DUMMY_RETURN }
/** Accessor function that returns the source index of the packet. */
- short getSrc() const { assert(srcValid); return src; }
+ short getSrc() const { assert(srcValid); return src; }
void setSrc(short _src) { src = _src; srcValid = true; }
+ /** Reset source field, e.g. to retransmit packet on different bus. */
+ void clearSrc() { srcValid = false; }
/** Accessor function that returns the destination index of
the packet. */
- short getDest() const { return dest; }
- void setDest(short _dest) { dest = _dest; }
+ short getDest() const { assert(destValid); return dest; }
+ void setDest(short _dest) { dest = _dest; destValid = true; }
Addr getAddr() const { assert(addrSizeValid); return addr; }
- int getSize() const { assert(addrSizeValid); return size; }
+ int getSize() const { assert(addrSizeValid); return size; }
Addr getOffset(int blkSize) const { return addr & (Addr)(blkSize - 1); }
- void addrOverride(Addr newAddr) { assert(addrSizeValid); addr = newAddr; }
- void cmdOverride(Command newCmd) { cmd = newCmd; }
-
/** Constructor. Note that a Request object must be constructed
* first, but the Requests's physical address and size fields
* need not be valid. The command and destination addresses
* must be supplied. */
- Packet(Request *_req, Command _cmd, short _dest)
- : data(NULL), staticData(false), dynamicData(false), arrayData(false),
+ Packet(Request *_req, MemCmd _cmd, short _dest)
+ : cmd(_cmd), req(_req),
+ data(NULL), staticData(false), dynamicData(false), arrayData(false),
addr(_req->paddr), size(_req->size), dest(_dest),
- addrSizeValid(_req->validPaddr),
- srcValid(false),
- req(_req), coherence(NULL), senderState(NULL), cmd(_cmd),
- result(Unknown)
+ addrSizeValid(_req->validPaddr), srcValid(false), destValid(true),
+ flags(0), time(curTick), senderState(NULL)
{
- flags = 0;
- time = curTick;
}
/** Alternate constructor if you are trying to create a packet with
* a request that is for a whole block, not the address from the req.
* this allows for overriding the size/addr of the req.*/
- Packet(Request *_req, Command _cmd, short _dest, int _blkSize)
- : data(NULL), staticData(false), dynamicData(false), arrayData(false),
- addr(_req->paddr & ~(_blkSize - 1)), size(_blkSize),
- dest(_dest),
- addrSizeValid(_req->validPaddr), srcValid(false),
- req(_req), coherence(NULL), senderState(NULL), cmd(_cmd),
- result(Unknown)
+ Packet(Request *_req, MemCmd _cmd, short _dest, int _blkSize)
+ : cmd(_cmd), req(_req),
+ data(NULL), staticData(false), dynamicData(false), arrayData(false),
+ addr(_req->paddr & ~(_blkSize - 1)), size(_blkSize), dest(_dest),
+ addrSizeValid(_req->validPaddr), srcValid(false), destValid(true),
+ flags(0), time(curTick), senderState(NULL)
+ {
+ }
+
+ /** Alternate constructor for copying a packet. Copy all fields
+ * *except* if the original packet's data was dynamic, don't copy
+ * that, as we can't guarantee that the new packet's lifetime is
+ * less than that of the original packet. In this case the new
+ * packet should allocate its own data. */
+ Packet(Packet *origPkt, bool clearFlags = false)
+ : cmd(origPkt->cmd), req(origPkt->req),
+ data(origPkt->staticData ? origPkt->data : NULL),
+ staticData(origPkt->staticData),
+ dynamicData(false), arrayData(false),
+ addr(origPkt->addr), size(origPkt->size),
+ src(origPkt->src), dest(origPkt->dest),
+ addrSizeValid(origPkt->addrSizeValid),
+ srcValid(origPkt->srcValid), destValid(origPkt->destValid),
+ flags(clearFlags ? 0 : origPkt->flags),
+ time(curTick), senderState(origPkt->senderState)
{
- flags = 0;
- time = curTick;
}
/** Destructor. */
~Packet()
- { deleteData(); }
+ { if (staticData || dynamicData) deleteData(); }
/** Reinitialize packet address and size from the associated
* Request object, and reset other fields that may have been
size = req->size;
time = req->time;
addrSizeValid = true;
- result = Unknown;
if (dynamicData) {
deleteData();
dynamicData = false;
}
}
- /** Take a request packet and modify it in place to be suitable
- * for returning as a response to that request. Used for timing
- * accesses only. For atomic and functional accesses, the
- * request packet is always implicitly passed back *without*
- * modifying the destination fields, so this function
- * should not be called. */
- void makeTimingResponse() {
+ /**
+ * Take a request packet and modify it in place to be suitable for
+ * returning as a response to that request. The source and
+ * destination fields are *not* modified, as is appropriate for
+ * atomic accesses.
+ */
+ void makeResponse()
+ {
assert(needsResponse());
assert(isRequest());
- int icmd = (int)cmd;
- icmd &= ~(IsRequest);
- icmd |= IsResponse;
- if (isRead())
- icmd |= HasData;
- if (isWrite())
- icmd &= ~HasData;
- cmd = (Command)icmd;
+ origCmd = cmd;
+ cmd = cmd.responseCommand();
dest = src;
+ destValid = srcValid;
srcValid = false;
}
-
- void toggleData() {
- int icmd = (int)cmd;
- icmd ^= HasData;
- cmd = (Command)icmd;
+ void makeAtomicResponse()
+ {
+ makeResponse();
}
- /**
- * Take a request packet and modify it in place to be suitable for
- * returning as a response to that request.
- */
- void makeAtomicResponse()
+ void makeTimingResponse()
{
- assert(needsResponse());
- assert(isRequest());
- int icmd = (int)cmd;
- icmd &= ~(IsRequest);
- icmd |= IsResponse;
- if (isRead())
- icmd |= HasData;
- if (isWrite())
- icmd &= ~HasData;
- cmd = (Command)icmd;
+ makeResponse();
}
/**
void
reinitNacked()
{
- assert(needsResponse() && result == Nacked);
- dest = Broadcast;
- result = Unknown;
+ assert(wasNacked());
+ cmd = origCmd;
+ assert(needsResponse());
+ setDest(Broadcast);
}
template <typename T>
void set(T v);
+ /**
+ * Copy data into the packet from the provided pointer.
+ */
+ void setData(uint8_t *p)
+ {
+ std::memcpy(getPtr<uint8_t>(), p, getSize());
+ }
+
+ /**
+ * Copy data into the packet from the provided block pointer,
+ * which is aligned to the given block size.
+ */
+ void setDataFromBlock(uint8_t *blk_data, int blkSize)
+ {
+ setData(blk_data + getOffset(blkSize));
+ }
+
+ /**
+ * Copy data from the packet to the provided block pointer, which
+ * is aligned to the given block size.
+ */
+ void writeData(uint8_t *p)
+ {
+ std::memcpy(p, getPtr<uint8_t>(), getSize());
+ }
+
+ /**
+ * Copy data from the packet to the memory at the provided pointer.
+ */
+ void writeDataToBlock(uint8_t *blk_data, int blkSize)
+ {
+ writeData(blk_data + getOffset(blkSize));
+ }
+
/**
* delete the data pointed to in the data pointer. Ok to call to
* matter how data was allocted.
/** If there isn't data in the packet, allocate some. */
void allocate();
- /** Do the packet modify the same addresses. */
- bool intersect(PacketPtr p);
-};
+ /**
+ * Check a functional request against a memory value represented
+ * by a base/size pair and an associated data array. If the
+ * functional request is a read, it may be satisfied by the memory
+ * value. If the functional request is a write, it may update the
+ * memory value.
+ */
+ bool checkFunctional(Printable *obj, Addr base, int size, uint8_t *data);
-/** This function given a functional packet and a timing packet either satisfies
- * the timing packet, or updates the timing packet to reflect the updated state
- * in the timing packet. It returns if the functional packet should continue to
- * traverse the memory hierarchy or not.
- */
-bool fixPacket(PacketPtr func, PacketPtr timing);
+ /**
+ * Check a functional request against a memory value stored in
+ * another packet (i.e. an in-transit request or response).
+ */
+ bool checkFunctional(PacketPtr otherPkt) {
+ return checkFunctional(otherPkt,
+ otherPkt->getAddr(), otherPkt->getSize(),
+ otherPkt->hasData() ?
+ otherPkt->getPtr<uint8_t>() : NULL);
+ }
-/** This function is a wrapper for the fixPacket field that toggles the hasData bit
- * it is used when a response is waiting in the caches, but hasn't been marked as a
- * response yet (so the fixPacket needs to get the correct value for the hasData)
- */
-bool fixDelayedResponsePacket(PacketPtr func, PacketPtr timing);
+ /**
+ * Push label for PrintReq (safe to call unconditionally).
+ */
+ void pushLabel(const std::string &lbl) {
+ if (isPrint()) {
+ dynamic_cast<PrintReqState*>(senderState)->pushLabel(lbl);
+ }
+ }
+
+ /**
+ * Pop label for PrintReq (safe to call unconditionally).
+ */
+ void popLabel() {
+ if (isPrint()) {
+ dynamic_cast<PrintReqState*>(senderState)->popLabel();
+ }
+ }
-std::ostream & operator<<(std::ostream &o, const Packet &p);
+ void print(std::ostream &o, int verbosity = 0,
+ const std::string &prefix = "") const;
+};
#endif //__MEM_PACKET_HH
projects / gem5.git / blobdiff