1/* 2 * Copyright 2018 Google, Inc. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are 6 * met: redistributions of source code must retain the above copyright 7 * notice, this list of conditions and the following disclaimer; 8 * redistributions in binary form must reproduce the above copyright --- 16 unchanged lines hidden (view full) --- 25 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 * 27 * Authors: Gabe Black 28 */ 29 30#include "systemc/core/scheduler.hh" 31 32#include "base/fiber.hh" |
33#include "base/logging.hh" 34#include "sim/eventq.hh" |
35 36namespace sc_gem5 37{ 38 |
39Scheduler::Scheduler() : 40 eq(nullptr), readyEvent(this, false, EventBase::Default_Pri + 1), 41 _numCycles(0), _current(nullptr) 42{} |
43 44void |
45Scheduler::initToReady() |
46{ |
47 while (!initList.empty()) 48 ready(initList.getNext()); |
49} 50 51void |
52Scheduler::yield() 53{ 54 _current = readyList.getNext(); 55 if (!_current) { 56 // There are no more processes, so return control to evaluate. 57 Fiber::primaryFiber()->run(); 58 } else { 59 _current->popListNode(); 60 // Switch to whatever Fiber is supposed to run this process. All 61 // Fibers which aren't running should be parked at this line. 62 _current->fiber()->run(); 63 // If the current process hasn't been started yet, start it. This 64 // should always be true for methods, but may not be true for threads. 65 if (_current && !_current->running()) 66 _current->run(); 67 } 68} 69 70void |
71Scheduler::ready(Process *p) |
72{ |
73 // Clump methods together to minimize context switching. 74 if (p->procKind() == ::sc_core::SC_METHOD_PROC_) 75 readyList.pushFirst(p); 76 else 77 readyList.pushLast(p); |
78 |
79 scheduleReadyEvent(); |
80} 81 82void |
83Scheduler::requestUpdate(Channel *c) |
84{ |
85 updateList.pushLast(c); 86 scheduleReadyEvent(); |
87} 88 89void |
90Scheduler::scheduleReadyEvent() |
91{ |
92 // Schedule the evaluate and update phases. 93 if (!readyEvent.scheduled()) { 94 panic_if(!eq, "Need to schedule ready, but no event manager.\n"); 95 eq->schedule(&readyEvent, eq->getCurTick()); 96 } |
97} 98 |
99void 100Scheduler::runReady() 101{ 102 bool empty = readyList.empty(); 103 104 // The evaluation phase. 105 do { 106 yield(); 107 } while (!readyList.empty()); 108 109 if (!empty) 110 _numCycles++; 111 112 // The update phase. 113 update(); 114 115 // The delta phase will happen naturally through the event queue. 116} 117 118void 119Scheduler::update() 120{ 121 Channel *channel = updateList.getNext(); 122 while (channel) { 123 channel->popListNode(); 124 channel->update(); 125 channel = updateList.getNext(); 126 } 127} 128 |
129Scheduler scheduler; 130 131} // namespace sc_gem5 |