gem5  v20.1.0.0
mshr_queue.hh
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40 
45 #ifndef __MEM_CACHE_MSHR_QUEUE_HH__
46 #define __MEM_CACHE_MSHR_QUEUE_HH__
47 
48 #include <string>
49 
50 #include "base/types.hh"
51 #include "mem/cache/mshr.hh"
52 #include "mem/cache/queue.hh"
53 #include "mem/packet.hh"
54 
58 class MSHRQueue : public Queue<MSHR>
59 {
60  private:
61 
66  const int demandReserve;
67 
68  public:
69 
78  MSHRQueue(const std::string &_label, int num_entries, int reserve,
79  int demand_reserve);
80 
96  MSHR *allocate(Addr blk_addr, unsigned blk_size, PacketPtr pkt,
97  Tick when_ready, Counter order, bool alloc_on_fill);
98 
104  void moveToFront(MSHR *mshr);
105 
113  void delay(MSHR *mshr, Tick delay_ticks);
114 
123  void markInService(MSHR *mshr, bool pending_modified_resp);
124 
129  void markPending(MSHR *mshr);
130 
135  bool forceDeallocateTarget(MSHR *mshr);
136 
141  bool havePending() const
142  {
143  return !readyList.empty();
144  }
145 
150  bool canPrefetch() const
151  {
152  // @todo we may want to revisit the +1, currently added to
153  // keep regressions unchanged
154  return (allocated < numEntries - (numReserve + 1 + demandReserve));
155  }
156 };
157 
158 #endif //__MEM_CACHE_MSHR_QUEUE_HH__
Queue< MSHR >::allocated
int allocated
The number of currently allocated entries.
Definition: queue.hh:119
Queue< MSHR >::readyList
MSHR ::List readyList
Holds pointers to entries that haven't been sent downstream.
Definition: queue.hh:96
mshr.hh
MSHRQueue::forceDeallocateTarget
bool forceDeallocateTarget(MSHR *mshr)
Deallocate top target, possibly freeing the MSHR.
Definition: mshr_queue.cc:117
MSHRQueue::markPending
void markPending(MSHR *mshr)
Mark an in service entry as pending, used to resend a request.
Definition: mshr_queue.cc:104
Tick
uint64_t Tick
Tick count type.
Definition: types.hh:63
MSHRQueue::moveToFront
void moveToFront(MSHR *mshr)
Moves the MSHR to the front of the pending list if it is not in service.
Definition: mshr_queue.cc:75
Queue< MSHR >::numReserve
const int numReserve
The number of entries to hold as a temporary overflow space.
Definition: queue.hh:89
packet.hh
Counter
int64_t Counter
Statistics counter type.
Definition: types.hh:58
MSHRQueue::delay
void delay(MSHR *mshr, Tick delay_ticks)
Adds a delay to the provided MSHR and moves MSHRs that will be ready earlier than this entry to the t...
Definition: mshr_queue.cc:85
Queue< MSHR >::numEntries
const int numEntries
The total number of entries in this queue.
Definition: queue.hh:81
MSHRQueue::demandReserve
const int demandReserve
The number of entries to reserve for future demand accesses.
Definition: mshr_queue.hh:66
MSHRQueue::canPrefetch
bool canPrefetch() const
Returns true if sufficient mshrs for prefetch.
Definition: mshr_queue.hh:150
Addr
uint64_t Addr
Address type This will probably be moved somewhere else in the near future.
Definition: types.hh:142
MSHRQueue::allocate
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:58
types.hh
Packet
A Packet is used to encapsulate a transfer between two objects in the memory system (e....
Definition: packet.hh:257
Queue
A high-level queue interface, to be used by both the MSHR queue and the write buffer.
Definition: queue.hh:66
MSHRQueue::havePending
bool havePending() const
Returns true if the pending list is not empty.
Definition: mshr_queue.hh:141
queue.hh
MSHRQueue::MSHRQueue
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:51
MSHRQueue
A Class for maintaining a list of pending and allocated memory requests.
Definition: mshr_queue.hh:58
MSHRQueue::markInService
void markInService(MSHR *mshr, bool pending_modified_resp)
Mark the given MSHR as in service.
Definition: mshr_queue.cc:96
MSHR
Miss Status and handling Register.
Definition: mshr.hh:69

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