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25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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37 * Authors: Matteo Andreozzi
40 #include "turnaround_policy_ideal.hh"
42 #include "params/QoSTurnaroundPolicyIdeal.hh"
46 TurnaroundPolicyIdeal::TurnaroundPolicyIdeal(const Params
* p
)
50 TurnaroundPolicyIdeal::~TurnaroundPolicyIdeal()
54 TurnaroundPolicyIdeal::selectBusState()
56 auto bus_state
= memCtrl
->getBusState();
57 const auto num_priorities
= memCtrl
->numPriorities();
59 // QoS-aware turnaround policy
60 // Loop for every queue in the memory controller.
61 for (uint8_t i
= 0; i
< num_priorities
; i
++) {
63 // Starting from top priority queues first
64 uint8_t queue_idx
= num_priorities
- i
- 1;
66 const uint64_t readq_size
= memCtrl
->getReadQueueSize(queue_idx
);
67 const uint64_t writeq_size
= memCtrl
->getWriteQueueSize(queue_idx
);
69 // No data for current priority: both the read queue
70 // and write queue are empty.
71 if ((readq_size
== 0) && (writeq_size
== 0)) {
75 // Data found - select state
76 if (readq_size
== 0) {
77 bus_state
= MemCtrl::WRITE
;
78 } else if (writeq_size
== 0) {
79 bus_state
= MemCtrl::READ
;
81 // readq_size > 0 && writeq_size > 0
82 bus_state
= ((memCtrl
->getBusState() == MemCtrl::READ
) ?
83 MemCtrl::WRITE
: MemCtrl::READ
);
87 "QoSMemoryTurnaround::QoSTurnaroundPolicyIdeal - "
88 "QoS priority %d queues %d, %d triggering bus %s "
89 "in state %s\n", queue_idx
, readq_size
, writeq_size
,
90 (bus_state
!= memCtrl
->getBusState()) ?
91 "turnaround" : "staying",
92 (bus_state
== MemCtrl::READ
)? "READ" : "WRITE");
93 // State selected - exit loop
102 QoS::TurnaroundPolicyIdeal
*
103 QoSTurnaroundPolicyIdealParams::create()
105 return new QoS::TurnaroundPolicyIdeal(this);