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-rw-r--r--src/mem/packet.hh304
1 files changed, 183 insertions, 121 deletions
diff --git a/src/mem/packet.hh b/src/mem/packet.hh
index fb077901e..2b650a51e 100644
--- a/src/mem/packet.hh
+++ b/src/mem/packet.hh
@@ -55,16 +55,6 @@ 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)
-
-
class MemCmd
{
public:
@@ -74,23 +64,33 @@ class MemCmd
{
InvalidCmd,
ReadReq,
- WriteReq,
- WriteReqNoAck,
ReadResp,
+ WriteReq,
WriteResp,
Writeback,
SoftPFReq,
HardPFReq,
SoftPFResp,
HardPFResp,
- InvalidateReq,
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
NUM_MEM_CMDS
};
@@ -98,18 +98,19 @@ class MemCmd
/** List of command attributes. */
enum Attribute
{
- IsRead,
- IsWrite,
- IsPrefetch,
+ IsRead, //!< Data flows from responder to requester
+ IsWrite, //!< Data flows from requester to responder
+ IsPrefetch, //!< Not a demand access
IsInvalidate,
- IsRequest,
- IsResponse,
- NeedsResponse,
+ NeedsExclusive, //!< Requires exclusive copy to complete in-cache
+ IsRequest, //!< Issued by requester
+ IsResponse, //!< Issue by responder
+ NeedsResponse, //!< Requester needs response from target
IsSWPrefetch,
IsHWPrefetch,
- IsUpgrade,
- HasData,
- IsReadWrite,
+ IsLocked, //!< Alpha/MIPS LL or SC access
+ HasData, //!< There is an associated payload
+ IsError, //!< Error response
NUM_COMMAND_ATTRIBUTES
};
@@ -142,10 +143,13 @@ class MemCmd
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 testCmdAttrib(IsReadWrite); }
+ bool isReadWrite() const { return isRead() && isWrite(); }
+ bool isLocked() const { return testCmdAttrib(IsLocked); }
+ bool isError() const { return testCmdAttrib(IsError); }
const Command responseCommand() const {
return commandInfo[cmd].response;
@@ -189,8 +193,11 @@ class Packet : public FastAlloc
typedef MemCmd::Command Command;
- /** Temporary FLAGS field until cache gets working, this should be in coherence/sender state. */
- uint64_t flags;
+ /** 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
@@ -231,11 +238,34 @@ class Packet : public FastAlloc
* (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:
@@ -252,22 +282,6 @@ class Packet : public FastAlloc
* 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 FastAlloc {
- 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
@@ -284,11 +298,6 @@ class Packet : public FastAlloc
* to cast to the state appropriate to the sender. */
SenderState *senderState;
- public:
-
- /** The command field of the packet. */
- MemCmd cmd;
-
/** Return the string name of the cmd field (for debugging and
* tracing). */
const std::string &cmdString() const { return cmd.toString(); }
@@ -296,80 +305,97 @@ class Packet : public FastAlloc
/** Return the index of this command. */
inline int cmdToIndex() const { return cmd.toInt(); }
- public:
-
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 isCacheFill() const { return (flags & CACHE_LINE_FILL) != 0; }
- bool isNoAllocate() const { return (flags & NO_ALLOCATE) != 0; }
- bool isCompressed() const { return (flags & COMPRESSED) != 0; }
+ bool isLocked() const { return cmd.isLocked(); }
+ bool isError() const { return cmd.isError(); }
+
+ // 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() { origCmd = cmd; cmd = MemCmd::NetworkNackError; }
+ void setBadAddress() { origCmd = cmd; cmd = MemCmd::BadAddressError; }
+ bool wasNacked() { return cmd == MemCmd::NetworkNackError; }
+ bool hadBadAddress() { return cmd == MemCmd::BadAddressError; }
bool nic_pkt() { panic("Unimplemented"); M5_DUMMY_RETURN }
- /** Possible results of a packet's request. */
- enum Result
- {
- Success,
- BadAddress,
- Nacked,
- Unknown
- };
-
- /** The result of this packet's request. */
- Result result;
-
/** 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(MemCmd 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, MemCmd _cmd, short _dest)
- : data(NULL), staticData(false), dynamicData(false), arrayData(false),
+ : 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, MemCmd _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)
+ : 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. */
@@ -388,7 +414,6 @@ class Packet : public FastAlloc
size = req->size;
time = req->time;
addrSizeValid = true;
- result = Unknown;
if (dynamicData) {
deleteData();
dynamicData = false;
@@ -396,29 +421,30 @@ class Packet : public FastAlloc
}
}
- /** 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());
cmd = cmd.responseCommand();
dest = src;
+ destValid = srcValid;
srcValid = false;
}
- /**
- * Take a request packet and modify it in place to be suitable for
- * returning as a response to that request.
- */
void makeAtomicResponse()
{
- assert(needsResponse());
- assert(isRequest());
- cmd = cmd.responseCommand();
+ makeResponse();
+ }
+
+ void makeTimingResponse()
+ {
+ makeResponse();
}
/**
@@ -429,9 +455,10 @@ class Packet : public FastAlloc
void
reinitNacked()
{
- assert(needsResponse() && result == Nacked);
- dest = Broadcast;
- result = Unknown;
+ assert(wasNacked());
+ cmd = origCmd;
+ assert(needsResponse());
+ setDest(Broadcast);
}
@@ -495,6 +522,40 @@ class Packet : public FastAlloc
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.
*/
@@ -503,24 +564,25 @@ class Packet : public FastAlloc
/** If there isn't data in the packet, allocate some. */
void allocate();
- /** Do the packet modify the same addresses. */
- bool intersect(PacketPtr p);
-};
-
-/** 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 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(Addr base, int size, uint8_t *data);
-/** 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);
+ /**
+ * 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 (otherPkt->hasData() &&
+ checkFunctional(otherPkt->getAddr(), otherPkt->getSize(),
+ otherPkt->getPtr<uint8_t>()));
+ }
+};
std::ostream & operator<<(std::ostream &o, const Packet &p);
generated by cgit v1.2.3 (git 2.25.1) at 2024-08-29 13:47:11 +0000