scheduler.cc revision 13176
112953Sgabeblack@google.com/* 212953Sgabeblack@google.com * Copyright 2018 Google, Inc. 312953Sgabeblack@google.com * 412953Sgabeblack@google.com * Redistribution and use in source and binary forms, with or without 512953Sgabeblack@google.com * modification, are permitted provided that the following conditions are 612953Sgabeblack@google.com * met: redistributions of source code must retain the above copyright 712953Sgabeblack@google.com * notice, this list of conditions and the following disclaimer; 812953Sgabeblack@google.com * redistributions in binary form must reproduce the above copyright 912953Sgabeblack@google.com * notice, this list of conditions and the following disclaimer in the 1012953Sgabeblack@google.com * documentation and/or other materials provided with the distribution; 1112953Sgabeblack@google.com * neither the name of the copyright holders nor the names of its 1212953Sgabeblack@google.com * contributors may be used to endorse or promote products derived from 1312953Sgabeblack@google.com * this software without specific prior written permission. 1412953Sgabeblack@google.com * 1512953Sgabeblack@google.com * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 1612953Sgabeblack@google.com * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 1712953Sgabeblack@google.com * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 1812953Sgabeblack@google.com * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 1912953Sgabeblack@google.com * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 2012953Sgabeblack@google.com * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 2112953Sgabeblack@google.com * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 2212953Sgabeblack@google.com * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 2312953Sgabeblack@google.com * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 2412953Sgabeblack@google.com * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 2512953Sgabeblack@google.com * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 2612953Sgabeblack@google.com * 2712953Sgabeblack@google.com * Authors: Gabe Black 2812953Sgabeblack@google.com */ 2912953Sgabeblack@google.com 3012953Sgabeblack@google.com#include "systemc/core/scheduler.hh" 3112953Sgabeblack@google.com 3212953Sgabeblack@google.com#include "base/fiber.hh" 3312954Sgabeblack@google.com#include "base/logging.hh" 3412954Sgabeblack@google.com#include "sim/eventq.hh" 3512982Sgabeblack@google.com#include "systemc/core/kernel.hh" 3612982Sgabeblack@google.com#include "systemc/ext/core/sc_main.hh" 3712953Sgabeblack@google.com 3812953Sgabeblack@google.comnamespace sc_gem5 3912953Sgabeblack@google.com{ 4012953Sgabeblack@google.com 4112954Sgabeblack@google.comScheduler::Scheduler() : 4212962Sgabeblack@google.com eq(nullptr), readyEvent(this, false, ReadyPriority), 4312961Sgabeblack@google.com pauseEvent(this, false, PausePriority), 4412961Sgabeblack@google.com stopEvent(this, false, StopPriority), 4512987Sgabeblack@google.com scMain(nullptr), 4612987Sgabeblack@google.com starvationEvent(this, false, StarvationPriority), 4713154Sgabeblack@google.com _started(false), _paused(false), _stopped(false), _stopNow(false), 4812961Sgabeblack@google.com maxTickEvent(this, false, MaxTickPriority), 4913140Sgabeblack@google.com _numCycles(0), _changeStamp(0), _current(nullptr), initDone(false), 5013176Sgabeblack@google.com runOnce(false), readyList(nullptr) 5112954Sgabeblack@google.com{} 5212953Sgabeblack@google.com 5313072Sgabeblack@google.comScheduler::~Scheduler() 5413072Sgabeblack@google.com{ 5513072Sgabeblack@google.com // Clear out everything that belongs to us to make sure nobody tries to 5613072Sgabeblack@google.com // clear themselves out after the scheduler goes away. 5713076Sgabeblack@google.com clear(); 5813076Sgabeblack@google.com} 5913072Sgabeblack@google.com 6013076Sgabeblack@google.comvoid 6113076Sgabeblack@google.comScheduler::clear() 6213076Sgabeblack@google.com{ 6313072Sgabeblack@google.com // Delta notifications. 6413144Sgabeblack@google.com while (!deltas.empty()) 6513144Sgabeblack@google.com deltas.front()->deschedule(); 6613072Sgabeblack@google.com 6713072Sgabeblack@google.com // Timed notifications. 6813076Sgabeblack@google.com for (auto &tsp: timeSlots) { 6913076Sgabeblack@google.com TimeSlot *&ts = tsp.second; 7013144Sgabeblack@google.com while (!ts->events.empty()) 7113144Sgabeblack@google.com ts->events.front()->deschedule(); 7213088Sgabeblack@google.com deschedule(ts); 7313072Sgabeblack@google.com } 7413076Sgabeblack@google.com timeSlots.clear(); 7513072Sgabeblack@google.com 7613072Sgabeblack@google.com // gem5 events. 7713072Sgabeblack@google.com if (readyEvent.scheduled()) 7813088Sgabeblack@google.com deschedule(&readyEvent); 7913072Sgabeblack@google.com if (pauseEvent.scheduled()) 8013088Sgabeblack@google.com deschedule(&pauseEvent); 8113072Sgabeblack@google.com if (stopEvent.scheduled()) 8213088Sgabeblack@google.com deschedule(&stopEvent); 8313072Sgabeblack@google.com if (starvationEvent.scheduled()) 8413088Sgabeblack@google.com deschedule(&starvationEvent); 8513072Sgabeblack@google.com if (maxTickEvent.scheduled()) 8613088Sgabeblack@google.com deschedule(&maxTickEvent); 8713072Sgabeblack@google.com 8813072Sgabeblack@google.com Process *p; 8913072Sgabeblack@google.com while ((p = toFinalize.getNext())) 9013072Sgabeblack@google.com p->popListNode(); 9113072Sgabeblack@google.com while ((p = initList.getNext())) 9213072Sgabeblack@google.com p->popListNode(); 9313176Sgabeblack@google.com while ((p = readyListMethods.getNext())) 9413176Sgabeblack@google.com p->popListNode(); 9513176Sgabeblack@google.com while ((p = readyListThreads.getNext())) 9613072Sgabeblack@google.com p->popListNode(); 9713072Sgabeblack@google.com 9813072Sgabeblack@google.com Channel *c; 9913072Sgabeblack@google.com while ((c = updateList.getNext())) 10013072Sgabeblack@google.com c->popListNode(); 10113072Sgabeblack@google.com} 10213072Sgabeblack@google.com 10312953Sgabeblack@google.comvoid 10413067Sgabeblack@google.comScheduler::initPhase() 10512953Sgabeblack@google.com{ 10612957Sgabeblack@google.com for (Process *p = toFinalize.getNext(); p; p = toFinalize.getNext()) { 10712957Sgabeblack@google.com p->finalize(); 10812957Sgabeblack@google.com p->popListNode(); 10912957Sgabeblack@google.com } 11012957Sgabeblack@google.com 11112957Sgabeblack@google.com for (Process *p = initList.getNext(); p; p = initList.getNext()) { 11212957Sgabeblack@google.com p->finalize(); 11312996Sgabeblack@google.com p->popListNode(); 11412959Sgabeblack@google.com p->ready(); 11512957Sgabeblack@google.com } 11612957Sgabeblack@google.com 11713067Sgabeblack@google.com update(); 11813067Sgabeblack@google.com 11913144Sgabeblack@google.com while (!deltas.empty()) 12013144Sgabeblack@google.com deltas.front()->run(); 12113067Sgabeblack@google.com 12212985Sgabeblack@google.com for (auto ets: eventsToSchedule) 12312985Sgabeblack@google.com eq->schedule(ets.first, ets.second); 12412985Sgabeblack@google.com eventsToSchedule.clear(); 12512985Sgabeblack@google.com 12613068Sgabeblack@google.com if (_started) { 12713096Sgabeblack@google.com if (!runToTime && starved()) 12813068Sgabeblack@google.com scheduleStarvationEvent(); 12913069Sgabeblack@google.com kernel->status(::sc_core::SC_RUNNING); 13013068Sgabeblack@google.com } 13112961Sgabeblack@google.com 13213067Sgabeblack@google.com initDone = true; 13312957Sgabeblack@google.com} 13412957Sgabeblack@google.com 13512957Sgabeblack@google.comvoid 13612957Sgabeblack@google.comScheduler::reg(Process *p) 13712957Sgabeblack@google.com{ 13813067Sgabeblack@google.com if (initDone) { 13912957Sgabeblack@google.com // If we're past initialization, finalize static sensitivity. 14012957Sgabeblack@google.com p->finalize(); 14112957Sgabeblack@google.com // Mark the process as ready. 14212959Sgabeblack@google.com p->ready(); 14312957Sgabeblack@google.com } else { 14412957Sgabeblack@google.com // Otherwise, record that this process should be initialized once we 14512957Sgabeblack@google.com // get there. 14612957Sgabeblack@google.com initList.pushLast(p); 14712957Sgabeblack@google.com } 14812957Sgabeblack@google.com} 14912957Sgabeblack@google.com 15012957Sgabeblack@google.comvoid 15112957Sgabeblack@google.comScheduler::dontInitialize(Process *p) 15212957Sgabeblack@google.com{ 15313067Sgabeblack@google.com if (initDone) { 15412957Sgabeblack@google.com // Pop this process off of the ready list. 15512957Sgabeblack@google.com p->popListNode(); 15612957Sgabeblack@google.com } else { 15712957Sgabeblack@google.com // Push this process onto the list of processes which still need 15812957Sgabeblack@google.com // their static sensitivity to be finalized. That implicitly pops it 15912957Sgabeblack@google.com // off the list of processes to be initialized/marked ready. 16012957Sgabeblack@google.com toFinalize.pushLast(p); 16112957Sgabeblack@google.com } 16212953Sgabeblack@google.com} 16312953Sgabeblack@google.com 16412953Sgabeblack@google.comvoid 16512953Sgabeblack@google.comScheduler::yield() 16612953Sgabeblack@google.com{ 16713176Sgabeblack@google.com // Pull a process from the active list. 16813176Sgabeblack@google.com _current = readyList->getNext(); 16912953Sgabeblack@google.com if (!_current) { 17012953Sgabeblack@google.com // There are no more processes, so return control to evaluate. 17112953Sgabeblack@google.com Fiber::primaryFiber()->run(); 17212953Sgabeblack@google.com } else { 17312953Sgabeblack@google.com _current->popListNode(); 17412953Sgabeblack@google.com // Switch to whatever Fiber is supposed to run this process. All 17512953Sgabeblack@google.com // Fibers which aren't running should be parked at this line. 17612953Sgabeblack@google.com _current->fiber()->run(); 17712961Sgabeblack@google.com // If the current process needs to be manually started, start it. 17813093Sgabeblack@google.com if (_current && _current->needsStart()) { 17913093Sgabeblack@google.com _current->needsStart(false); 18012953Sgabeblack@google.com _current->run(); 18113093Sgabeblack@google.com } 18212953Sgabeblack@google.com } 18312995Sgabeblack@google.com if (_current && _current->excWrapper) { 18412995Sgabeblack@google.com // Make sure this isn't a method process. 18512995Sgabeblack@google.com assert(!_current->needsStart()); 18612995Sgabeblack@google.com auto ew = _current->excWrapper; 18712995Sgabeblack@google.com _current->excWrapper = nullptr; 18812995Sgabeblack@google.com ew->throw_it(); 18912995Sgabeblack@google.com } 19012953Sgabeblack@google.com} 19112953Sgabeblack@google.com 19212953Sgabeblack@google.comvoid 19312954Sgabeblack@google.comScheduler::ready(Process *p) 19412953Sgabeblack@google.com{ 19513154Sgabeblack@google.com if (_stopNow) 19613154Sgabeblack@google.com return; 19713154Sgabeblack@google.com 19813176Sgabeblack@google.com if (p->procKind() == ::sc_core::SC_METHOD_PROC_) 19913176Sgabeblack@google.com readyListMethods.pushLast(p); 20012954Sgabeblack@google.com else 20113176Sgabeblack@google.com readyListThreads.pushLast(p); 20212953Sgabeblack@google.com 20312954Sgabeblack@google.com scheduleReadyEvent(); 20412954Sgabeblack@google.com} 20512954Sgabeblack@google.com 20612954Sgabeblack@google.comvoid 20713133Sgabeblack@google.comScheduler::resume(Process *p) 20813133Sgabeblack@google.com{ 20913133Sgabeblack@google.com if (initDone) 21013133Sgabeblack@google.com ready(p); 21113133Sgabeblack@google.com else 21213133Sgabeblack@google.com initList.pushLast(p); 21313133Sgabeblack@google.com} 21413133Sgabeblack@google.com 21513133Sgabeblack@google.combool 21613176Sgabeblack@google.comlistContains(ListNode *list, ListNode *target) 21713176Sgabeblack@google.com{ 21813176Sgabeblack@google.com ListNode *n = list->nextListNode; 21913176Sgabeblack@google.com while (n != list) 22013176Sgabeblack@google.com if (n == target) 22113176Sgabeblack@google.com return true; 22213176Sgabeblack@google.com return false; 22313176Sgabeblack@google.com} 22413176Sgabeblack@google.com 22513176Sgabeblack@google.combool 22613133Sgabeblack@google.comScheduler::suspend(Process *p) 22713133Sgabeblack@google.com{ 22813176Sgabeblack@google.com bool was_ready; 22913133Sgabeblack@google.com if (initDone) { 23013133Sgabeblack@google.com // After initialization, the only list we can be on is the ready list. 23113176Sgabeblack@google.com was_ready = (p->nextListNode != nullptr); 23213133Sgabeblack@google.com p->popListNode(); 23313133Sgabeblack@google.com } else { 23413176Sgabeblack@google.com // Check the ready lists to see if we find this process. 23513176Sgabeblack@google.com was_ready = listContains(&readyListMethods, p) || 23613176Sgabeblack@google.com listContains(&readyListThreads, p); 23713133Sgabeblack@google.com if (was_ready) 23813133Sgabeblack@google.com toFinalize.pushLast(p); 23913133Sgabeblack@google.com } 24013176Sgabeblack@google.com return was_ready; 24113133Sgabeblack@google.com} 24213133Sgabeblack@google.com 24313133Sgabeblack@google.comvoid 24412954Sgabeblack@google.comScheduler::requestUpdate(Channel *c) 24512954Sgabeblack@google.com{ 24612954Sgabeblack@google.com updateList.pushLast(c); 24713069Sgabeblack@google.com scheduleReadyEvent(); 24812954Sgabeblack@google.com} 24912954Sgabeblack@google.com 25012954Sgabeblack@google.comvoid 25112954Sgabeblack@google.comScheduler::scheduleReadyEvent() 25212954Sgabeblack@google.com{ 25312954Sgabeblack@google.com // Schedule the evaluate and update phases. 25412954Sgabeblack@google.com if (!readyEvent.scheduled()) { 25513069Sgabeblack@google.com schedule(&readyEvent); 25612987Sgabeblack@google.com if (starvationEvent.scheduled()) 25713069Sgabeblack@google.com deschedule(&starvationEvent); 25812987Sgabeblack@google.com } 25912987Sgabeblack@google.com} 26012987Sgabeblack@google.com 26112987Sgabeblack@google.comvoid 26212987Sgabeblack@google.comScheduler::scheduleStarvationEvent() 26312987Sgabeblack@google.com{ 26412987Sgabeblack@google.com if (!starvationEvent.scheduled()) { 26513069Sgabeblack@google.com schedule(&starvationEvent); 26612987Sgabeblack@google.com if (readyEvent.scheduled()) 26713069Sgabeblack@google.com deschedule(&readyEvent); 26812954Sgabeblack@google.com } 26912954Sgabeblack@google.com} 27012954Sgabeblack@google.com 27112954Sgabeblack@google.comvoid 27212954Sgabeblack@google.comScheduler::runReady() 27312954Sgabeblack@google.com{ 27413176Sgabeblack@google.com bool empty = readyListMethods.empty() && readyListThreads.empty(); 27513140Sgabeblack@google.com lastReadyTick = getCurTick(); 27612954Sgabeblack@google.com 27712954Sgabeblack@google.com // The evaluation phase. 27812953Sgabeblack@google.com do { 27913176Sgabeblack@google.com // We run methods and threads in two seperate passes to emulate how 28013176Sgabeblack@google.com // Accellera orders things, but without having to scan through a 28113176Sgabeblack@google.com // unified list to find the next process of the correct type. 28213176Sgabeblack@google.com readyList = &readyListMethods; 28313176Sgabeblack@google.com while (!readyListMethods.empty()) 28413176Sgabeblack@google.com yield(); 28513176Sgabeblack@google.com 28613176Sgabeblack@google.com readyList = &readyListThreads; 28713176Sgabeblack@google.com while (!readyListThreads.empty()) 28813176Sgabeblack@google.com yield(); 28913176Sgabeblack@google.com 29013176Sgabeblack@google.com // We already know that readyListThreads is empty at this point. 29113176Sgabeblack@google.com } while (!readyListMethods.empty()); 29212954Sgabeblack@google.com 29313140Sgabeblack@google.com if (!empty) { 29412954Sgabeblack@google.com _numCycles++; 29513140Sgabeblack@google.com _changeStamp++; 29613140Sgabeblack@google.com } 29712954Sgabeblack@google.com 29813154Sgabeblack@google.com if (_stopNow) 29913154Sgabeblack@google.com return; 30013154Sgabeblack@google.com 30112954Sgabeblack@google.com // The update phase. 30212954Sgabeblack@google.com update(); 30312954Sgabeblack@google.com 30413063Sgabeblack@google.com // The delta phase. 30513144Sgabeblack@google.com while (!deltas.empty()) 30613144Sgabeblack@google.com deltas.front()->run(); 30713061Sgabeblack@google.com 30813096Sgabeblack@google.com if (!runToTime && starved()) 30913096Sgabeblack@google.com scheduleStarvationEvent(); 31013096Sgabeblack@google.com 31113064Sgabeblack@google.com if (runOnce) 31213064Sgabeblack@google.com schedulePause(); 31312953Sgabeblack@google.com} 31412953Sgabeblack@google.com 31512953Sgabeblack@google.comvoid 31612953Sgabeblack@google.comScheduler::update() 31712953Sgabeblack@google.com{ 31812954Sgabeblack@google.com Channel *channel = updateList.getNext(); 31912954Sgabeblack@google.com while (channel) { 32012954Sgabeblack@google.com channel->popListNode(); 32112954Sgabeblack@google.com channel->update(); 32212954Sgabeblack@google.com channel = updateList.getNext(); 32312954Sgabeblack@google.com } 32412953Sgabeblack@google.com} 32512953Sgabeblack@google.com 32612961Sgabeblack@google.comvoid 32712961Sgabeblack@google.comScheduler::pause() 32812961Sgabeblack@google.com{ 32912961Sgabeblack@google.com _paused = true; 33012982Sgabeblack@google.com kernel->status(::sc_core::SC_PAUSED); 33113061Sgabeblack@google.com runOnce = false; 33212961Sgabeblack@google.com scMain->run(); 33312961Sgabeblack@google.com} 33412961Sgabeblack@google.com 33512961Sgabeblack@google.comvoid 33612961Sgabeblack@google.comScheduler::stop() 33712961Sgabeblack@google.com{ 33812961Sgabeblack@google.com _stopped = true; 33912982Sgabeblack@google.com kernel->stop(); 34013074Sgabeblack@google.com 34113076Sgabeblack@google.com clear(); 34213074Sgabeblack@google.com 34313061Sgabeblack@google.com runOnce = false; 34412961Sgabeblack@google.com scMain->run(); 34512961Sgabeblack@google.com} 34612961Sgabeblack@google.com 34712961Sgabeblack@google.comvoid 34812961Sgabeblack@google.comScheduler::start(Tick max_tick, bool run_to_time) 34912961Sgabeblack@google.com{ 35012961Sgabeblack@google.com // We should be running from sc_main. Keep track of that Fiber to return 35112961Sgabeblack@google.com // to later. 35212961Sgabeblack@google.com scMain = Fiber::currentFiber(); 35312961Sgabeblack@google.com 35412961Sgabeblack@google.com _started = true; 35512961Sgabeblack@google.com _paused = false; 35612961Sgabeblack@google.com _stopped = false; 35712987Sgabeblack@google.com runToTime = run_to_time; 35812961Sgabeblack@google.com 35912961Sgabeblack@google.com maxTick = max_tick; 36013140Sgabeblack@google.com lastReadyTick = getCurTick(); 36112961Sgabeblack@google.com 36213067Sgabeblack@google.com if (initDone) { 36313096Sgabeblack@google.com if (!runToTime && starved()) 36413068Sgabeblack@google.com scheduleStarvationEvent(); 36512982Sgabeblack@google.com kernel->status(::sc_core::SC_RUNNING); 36612982Sgabeblack@google.com } 36712961Sgabeblack@google.com 36813069Sgabeblack@google.com schedule(&maxTickEvent, maxTick); 36913069Sgabeblack@google.com 37012961Sgabeblack@google.com // Return to gem5 to let it run events, etc. 37112961Sgabeblack@google.com Fiber::primaryFiber()->run(); 37212961Sgabeblack@google.com 37312961Sgabeblack@google.com if (pauseEvent.scheduled()) 37413088Sgabeblack@google.com deschedule(&pauseEvent); 37512961Sgabeblack@google.com if (stopEvent.scheduled()) 37613088Sgabeblack@google.com deschedule(&stopEvent); 37712961Sgabeblack@google.com if (maxTickEvent.scheduled()) 37813088Sgabeblack@google.com deschedule(&maxTickEvent); 37912987Sgabeblack@google.com if (starvationEvent.scheduled()) 38013088Sgabeblack@google.com deschedule(&starvationEvent); 38112961Sgabeblack@google.com} 38212961Sgabeblack@google.com 38312961Sgabeblack@google.comvoid 38413061Sgabeblack@google.comScheduler::oneCycle() 38513061Sgabeblack@google.com{ 38613061Sgabeblack@google.com runOnce = true; 38713095Sgabeblack@google.com scheduleReadyEvent(); 38813061Sgabeblack@google.com start(::MaxTick, false); 38913061Sgabeblack@google.com} 39013061Sgabeblack@google.com 39113061Sgabeblack@google.comvoid 39212961Sgabeblack@google.comScheduler::schedulePause() 39312961Sgabeblack@google.com{ 39412961Sgabeblack@google.com if (pauseEvent.scheduled()) 39512961Sgabeblack@google.com return; 39612961Sgabeblack@google.com 39713088Sgabeblack@google.com schedule(&pauseEvent); 39812961Sgabeblack@google.com} 39912961Sgabeblack@google.com 40012961Sgabeblack@google.comvoid 40112961Sgabeblack@google.comScheduler::scheduleStop(bool finish_delta) 40212961Sgabeblack@google.com{ 40312961Sgabeblack@google.com if (stopEvent.scheduled()) 40412961Sgabeblack@google.com return; 40512961Sgabeblack@google.com 40612961Sgabeblack@google.com if (!finish_delta) { 40713154Sgabeblack@google.com _stopNow = true; 40813076Sgabeblack@google.com // If we're not supposed to finish the delta cycle, flush all 40913076Sgabeblack@google.com // pending activity. 41013076Sgabeblack@google.com clear(); 41112961Sgabeblack@google.com } 41213088Sgabeblack@google.com schedule(&stopEvent); 41312961Sgabeblack@google.com} 41412961Sgabeblack@google.com 41512953Sgabeblack@google.comScheduler scheduler; 41612953Sgabeblack@google.com 41712953Sgabeblack@google.com} // namespace sc_gem5 418