gem5  v22.0.0.2
turnaround_policy_ideal.cc
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37 
39 
40 #include <cstdint>
41 
42 #include "base/trace.hh"
43 #include "params/QoSTurnaroundPolicyIdeal.hh"
44 
45 namespace gem5
46 {
47 
48 namespace memory
49 {
50 
52 namespace qos
53 {
54 
57 {}
58 
60 {}
61 
64 {
65  auto bus_state = memCtrl->getBusState();
66  const auto num_priorities = memCtrl->numPriorities();
67 
68  // QoS-aware turnaround policy
69  // Loop for every queue in the memory controller.
70  for (uint8_t i = 0; i < num_priorities; i++) {
71 
72  // Starting from top priority queues first
73  uint8_t queue_idx = num_priorities - i - 1;
74 
75  const uint64_t readq_size = memCtrl->getReadQueueSize(queue_idx);
76  const uint64_t writeq_size = memCtrl->getWriteQueueSize(queue_idx);
77 
78  // No data for current priority: both the read queue
79  // and write queue are empty.
80  if ((readq_size == 0) && (writeq_size == 0)) {
81  continue;
82  }
83 
84  // Data found - select state
85  if (readq_size == 0) {
86  bus_state = MemCtrl::WRITE;
87  } else if (writeq_size == 0) {
88  bus_state = MemCtrl::READ;
89  } else {
90  // readq_size > 0 && writeq_size > 0
91  bus_state = ((memCtrl->getBusState() == MemCtrl::READ) ?
93  }
94 
95  DPRINTF(QOS,
96  "QoSMemoryTurnaround::QoSTurnaroundPolicyIdeal - "
97  "QoS priority %d queues %d, %d triggering bus %s "
98  "in state %s\n", queue_idx, readq_size, writeq_size,
99  (bus_state != memCtrl->getBusState()) ?
100  "turnaround" : "staying",
101  (bus_state == MemCtrl::READ)? "READ" : "WRITE");
102  // State selected - exit loop
103  break;
104  }
105 
106  return bus_state;
107 }
108 
109 } // namespace qos
110 } // namespace memory
111 } // namespace gem5
gem5::memory::qos::TurnaroundPolicy
Base class for QoS Bus Turnaround policies.
Definition: turnaround_policy.hh:59
memory
Definition: mem.h:38
gem5::memory::qos::MemCtrl::READ
@ READ
Definition: mem_ctrl.hh:84
gem5::memory::qos::TurnaroundPolicyIdeal::TurnaroundPolicyIdeal
TurnaroundPolicyIdeal(const Params &)
Definition: turnaround_policy_ideal.cc:55
gem5::memory::qos::TurnaroundPolicy::memCtrl
MemCtrl * memCtrl
Pointer to container object.
Definition: turnaround_policy.hh:84
gem5::memory::GEM5_DEPRECATED_NAMESPACE
GEM5_DEPRECATED_NAMESPACE(QoS, qos)
gem5::memory::qos::MemCtrl::getReadQueueSize
uint64_t getReadQueueSize(const uint8_t prio) const
Gets a READ queue size.
Definition: mem_ctrl.hh:327
gem5::ArmISA::i
Bitfield< 7 > i
Definition: misc_types.hh:67
gem5::memory::qos::MemCtrl::BusState
BusState
Bus Direction.
Definition: mem_ctrl.hh:84
gem5::memory::qos::TurnaroundPolicyIdeal::selectBusState
virtual MemCtrl::BusState selectBusState() override
Bus Selection function.
Definition: turnaround_policy_ideal.cc:63
gem5::VegaISA::p
Bitfield< 54 > p
Definition: pagetable.hh:70
DPRINTF
#define DPRINTF(x,...)
Definition: trace.hh:186
gem5::memory::qos::MemCtrl::getWriteQueueSize
uint64_t getWriteQueueSize(const uint8_t prio) const
Gets a WRITE queue size.
Definition: mem_ctrl.hh:336
gem5::memory::qos::TurnaroundPolicyIdeal::~TurnaroundPolicyIdeal
virtual ~TurnaroundPolicyIdeal()
Definition: turnaround_policy_ideal.cc:59
turnaround_policy_ideal.hh
gem5::memory::qos::MemCtrl::getBusState
BusState getBusState() const
Gets the current bus state.
Definition: mem_ctrl.hh:297
gem5::memory::qos::MemCtrl::numPriorities
uint8_t numPriorities() const
Gets the total number of priority levels in the QoS memory controller.
Definition: mem_ctrl.hh:367
gem5::memory::qos::MemCtrl::WRITE
@ WRITE
Definition: mem_ctrl.hh:84
trace.hh
gem5
Reference material can be found at the JEDEC website: UFS standard http://www.jedec....
Definition: gpu_translation_state.hh:37
gem5::memory::qos::TurnaroundPolicy::Params
QoSTurnaroundPolicyParams Params
Definition: turnaround_policy.hh:62

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