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mshr_queue.hh
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43 
48 #ifndef __MEM_CACHE_MSHR_QUEUE_HH__
49 #define __MEM_CACHE_MSHR_QUEUE_HH__
50 
51 #include <vector>
52 
53 #include "mem/cache/mshr.hh"
54 #include "mem/cache/queue.hh"
55 
59 class MSHRQueue : public Queue<MSHR>
60 {
61  private:
62 
67  const int demandReserve;
68 
69  public:
70 
79  MSHRQueue(const std::string &_label, int num_entries, int reserve,
80  int demand_reserve);
81 
97  MSHR *allocate(Addr blk_addr, unsigned blk_size, PacketPtr pkt,
98  Tick when_ready, Counter order, bool alloc_on_fill);
99 
105  void moveToFront(MSHR *mshr);
106 
115  void markInService(MSHR *mshr, bool pending_modified_resp);
116 
121  void markPending(MSHR *mshr);
122 
127  bool forceDeallocateTarget(MSHR *mshr);
128 
133  bool havePending() const
134  {
135  return !readyList.empty();
136  }
137 
142  bool canPrefetch() const
143  {
144  // @todo we may want to revisit the +1, currently added to
145  // keep regressions unchanged
146  return (allocated < numEntries - (numReserve + 1 + demandReserve));
147  }
148 };
149 
150 #endif //__MEM_CACHE_MSHR_QUEUE_HH__
Miss Status and Handling Register (MSHR) declaration.
Declaration of a high-level queue structure.
A Class for maintaining a list of pending and allocated memory requests.
Definition: mshr_queue.hh:59
MSHR::List readyList
Holds pointers to entries that haven't been sent downstream.
Definition: queue.hh:91
bool forceDeallocateTarget(MSHR *mshr)
Deallocate top target, possibly freeing the MSHR.
Definition: mshr_queue.cc:107
const int numReserve
The number of entries to hold as a temporary overflow space.
Definition: queue.hh:84
void moveToFront(MSHR *mshr)
Moves the MSHR to the front of the pending list if it is not in service.
Definition: mshr_queue.cc:76
A high-level queue interface, to be used by both the MSHR queue and the write buffer.
Definition: queue.hh:64
void markPending(MSHR *mshr)
Mark an in service entry as pending, used to resend a request.
Definition: mshr_queue.cc:94
bool havePending() const
Returns true if the pending list is not empty.
Definition: mshr_queue.hh:133
MSHR * allocate(Addr blk_addr, unsigned blk_size, PacketPtr pkt, Tick when_ready, Counter order, bool alloc_on_fill)
Allocates a new MSHR for the request and size.
Definition: mshr_queue.cc:59
uint64_t Tick
Tick count type.
Definition: types.hh:63
Miss Status and handling Register.
Definition: mshr.hh:63
void markInService(MSHR *mshr, bool pending_modified_resp)
Mark the given MSHR as in service.
Definition: mshr_queue.cc:86
const int numEntries
The total number of entries in this queue.
Definition: queue.hh:76
uint64_t Addr
Address type This will probably be moved somewhere else in the near future.
Definition: types.hh:142
int64_t Counter
Statistics counter type.
Definition: types.hh:58
A Packet is used to encapsulate a transfer between two objects in the memory system (e...
Definition: packet.hh:245
const int demandReserve
The number of entries to reserve for future demand accesses.
Definition: mshr_queue.hh:67
bool canPrefetch() const
Returns true if sufficient mshrs for prefetch.
Definition: mshr_queue.hh:142
MSHRQueue(const std::string &_label, int num_entries, int reserve, int demand_reserve)
Create a queue with a given number of entries.
Definition: mshr_queue.cc:52
int allocated
The number of currently allocated entries.
Definition: queue.hh:115

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