ef6e2eb3c4
cpu/o3/alpha_cpu.hh: Update for sampler to work properly. Also code cleanup. cpu/o3/alpha_cpu_builder.cc: cpu/o3/alpha_dyn_inst.hh: Updates to support the checker. cpu/o3/alpha_cpu_impl.hh: Updates to support the checker. Also general code cleanup. cpu/o3/alpha_dyn_inst_impl.hh: Code cleanup. cpu/o3/alpha_params.hh: Updates to support the checker. Also supports trap latencies set through the parameters. cpu/o3/commit.hh: Supports sampler, checker. Code cleanup. cpu/o3/commit_impl.hh: Updates to support the sampler and checker, as well as general code cleanup. cpu/o3/cpu.cc: cpu/o3/cpu.hh: Support sampler and checker. cpu/o3/decode_impl.hh: Supports sampler. cpu/o3/fetch.hh: Supports sampler. Also update to hold the youngest valid SN fetch has seen to ensure that the entire pipeline has been drained. cpu/o3/fetch_impl.hh: Sampler updates. Also be sure to not fetches to uncached space (bad path). cpu/o3/iew.hh: cpu/o3/iew_impl.hh: Sampler updates. cpu/o3/lsq_unit_impl.hh: Supports checker. cpu/o3/regfile.hh: No need for accessing xcProxies directly. cpu/o3/rename.hh: cpu/o3/rename_impl.hh: Sampler support. --HG-- extra : convert_revision : 03881885dd50ebbca13ef31f31492fd4ef59121c
1364 lines
39 KiB
C++
1364 lines
39 KiB
C++
/*
|
|
* Copyright (c) 2004-2006 The Regents of The University of Michigan
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions are
|
|
* met: redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer;
|
|
* redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution;
|
|
* neither the name of the copyright holders nor the names of its
|
|
* contributors may be used to endorse or promote products derived from
|
|
* this software without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
|
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
|
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
|
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
|
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
|
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <algorithm>
|
|
#include <cstdio>
|
|
#include <cstdlib>
|
|
#include <cstring>
|
|
#include <iomanip>
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
|
|
#include "base/loader/symtab.hh"
|
|
#include "base/timebuf.hh"
|
|
#include "cpu/checker/cpu.hh"
|
|
#include "cpu/exetrace.hh"
|
|
#include "cpu/o3/commit.hh"
|
|
#include "cpu/o3/thread_state.hh"
|
|
|
|
using namespace std;
|
|
|
|
template <class Impl>
|
|
DefaultCommit<Impl>::TrapEvent::TrapEvent(DefaultCommit<Impl> *_commit,
|
|
unsigned _tid)
|
|
: Event(&mainEventQueue, CPU_Tick_Pri), commit(_commit), tid(_tid)
|
|
{
|
|
this->setFlags(Event::AutoDelete);
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::TrapEvent::process()
|
|
{
|
|
// This will get reset by commit if it was switched out at the
|
|
// time of this event processing.
|
|
commit->trapSquash[tid] = true;
|
|
}
|
|
|
|
template <class Impl>
|
|
const char *
|
|
DefaultCommit<Impl>::TrapEvent::description()
|
|
{
|
|
return "Trap event";
|
|
}
|
|
|
|
template <class Impl>
|
|
DefaultCommit<Impl>::DefaultCommit(Params *params)
|
|
: dcacheInterface(params->dcacheInterface),
|
|
squashCounter(0),
|
|
iewToCommitDelay(params->iewToCommitDelay),
|
|
commitToIEWDelay(params->commitToIEWDelay),
|
|
renameToROBDelay(params->renameToROBDelay),
|
|
fetchToCommitDelay(params->commitToFetchDelay),
|
|
renameWidth(params->renameWidth),
|
|
iewWidth(params->executeWidth),
|
|
commitWidth(params->commitWidth),
|
|
numThreads(params->numberOfThreads),
|
|
switchedOut(false),
|
|
trapLatency(params->trapLatency),
|
|
fetchTrapLatency(params->fetchTrapLatency)
|
|
{
|
|
_status = Active;
|
|
_nextStatus = Inactive;
|
|
string policy = params->smtCommitPolicy;
|
|
|
|
//Convert string to lowercase
|
|
std::transform(policy.begin(), policy.end(), policy.begin(),
|
|
(int(*)(int)) tolower);
|
|
|
|
//Assign commit policy
|
|
if (policy == "aggressive"){
|
|
commitPolicy = Aggressive;
|
|
|
|
DPRINTF(Commit,"Commit Policy set to Aggressive.");
|
|
} else if (policy == "roundrobin"){
|
|
commitPolicy = RoundRobin;
|
|
|
|
//Set-Up Priority List
|
|
for (int tid=0; tid < numThreads; tid++) {
|
|
priority_list.push_back(tid);
|
|
}
|
|
|
|
DPRINTF(Commit,"Commit Policy set to Round Robin.");
|
|
} else if (policy == "oldestready"){
|
|
commitPolicy = OldestReady;
|
|
|
|
DPRINTF(Commit,"Commit Policy set to Oldest Ready.");
|
|
} else {
|
|
assert(0 && "Invalid SMT Commit Policy. Options Are: {Aggressive,"
|
|
"RoundRobin,OldestReady}");
|
|
}
|
|
|
|
for (int i=0; i < numThreads; i++) {
|
|
commitStatus[i] = Idle;
|
|
changedROBNumEntries[i] = false;
|
|
trapSquash[i] = false;
|
|
xcSquash[i] = false;
|
|
}
|
|
|
|
fetchFaultTick = 0;
|
|
fetchTrapWait = 0;
|
|
}
|
|
|
|
template <class Impl>
|
|
std::string
|
|
DefaultCommit<Impl>::name() const
|
|
{
|
|
return cpu->name() + ".commit";
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::regStats()
|
|
{
|
|
using namespace Stats;
|
|
commitCommittedInsts
|
|
.name(name() + ".commitCommittedInsts")
|
|
.desc("The number of committed instructions")
|
|
.prereq(commitCommittedInsts);
|
|
commitSquashedInsts
|
|
.name(name() + ".commitSquashedInsts")
|
|
.desc("The number of squashed insts skipped by commit")
|
|
.prereq(commitSquashedInsts);
|
|
commitSquashEvents
|
|
.name(name() + ".commitSquashEvents")
|
|
.desc("The number of times commit is told to squash")
|
|
.prereq(commitSquashEvents);
|
|
commitNonSpecStalls
|
|
.name(name() + ".commitNonSpecStalls")
|
|
.desc("The number of times commit has been forced to stall to "
|
|
"communicate backwards")
|
|
.prereq(commitNonSpecStalls);
|
|
branchMispredicts
|
|
.name(name() + ".branchMispredicts")
|
|
.desc("The number of times a branch was mispredicted")
|
|
.prereq(branchMispredicts);
|
|
numCommittedDist
|
|
.init(0,commitWidth,1)
|
|
.name(name() + ".COM:committed_per_cycle")
|
|
.desc("Number of insts commited each cycle")
|
|
.flags(Stats::pdf)
|
|
;
|
|
|
|
statComInst
|
|
.init(cpu->number_of_threads)
|
|
.name(name() + ".COM:count")
|
|
.desc("Number of instructions committed")
|
|
.flags(total)
|
|
;
|
|
|
|
statComSwp
|
|
.init(cpu->number_of_threads)
|
|
.name(name() + ".COM:swp_count")
|
|
.desc("Number of s/w prefetches committed")
|
|
.flags(total)
|
|
;
|
|
|
|
statComRefs
|
|
.init(cpu->number_of_threads)
|
|
.name(name() + ".COM:refs")
|
|
.desc("Number of memory references committed")
|
|
.flags(total)
|
|
;
|
|
|
|
statComLoads
|
|
.init(cpu->number_of_threads)
|
|
.name(name() + ".COM:loads")
|
|
.desc("Number of loads committed")
|
|
.flags(total)
|
|
;
|
|
|
|
statComMembars
|
|
.init(cpu->number_of_threads)
|
|
.name(name() + ".COM:membars")
|
|
.desc("Number of memory barriers committed")
|
|
.flags(total)
|
|
;
|
|
|
|
statComBranches
|
|
.init(cpu->number_of_threads)
|
|
.name(name() + ".COM:branches")
|
|
.desc("Number of branches committed")
|
|
.flags(total)
|
|
;
|
|
|
|
//
|
|
// Commit-Eligible instructions...
|
|
//
|
|
// -> The number of instructions eligible to commit in those
|
|
// cycles where we reached our commit BW limit (less the number
|
|
// actually committed)
|
|
//
|
|
// -> The average value is computed over ALL CYCLES... not just
|
|
// the BW limited cycles
|
|
//
|
|
// -> The standard deviation is computed only over cycles where
|
|
// we reached the BW limit
|
|
//
|
|
commitEligible
|
|
.init(cpu->number_of_threads)
|
|
.name(name() + ".COM:bw_limited")
|
|
.desc("number of insts not committed due to BW limits")
|
|
.flags(total)
|
|
;
|
|
|
|
commitEligibleSamples
|
|
.name(name() + ".COM:bw_lim_events")
|
|
.desc("number cycles where commit BW limit reached")
|
|
;
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::setCPU(FullCPU *cpu_ptr)
|
|
{
|
|
DPRINTF(Commit, "Commit: Setting CPU pointer.\n");
|
|
cpu = cpu_ptr;
|
|
|
|
// Commit must broadcast the number of free entries it has at the start of
|
|
// the simulation, so it starts as active.
|
|
cpu->activateStage(FullCPU::CommitIdx);
|
|
|
|
trapLatency = cpu->cycles(trapLatency);
|
|
fetchTrapLatency = cpu->cycles(fetchTrapLatency);
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::setThreads(vector<Thread *> &threads)
|
|
{
|
|
thread = threads;
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::setTimeBuffer(TimeBuffer<TimeStruct> *tb_ptr)
|
|
{
|
|
DPRINTF(Commit, "Commit: Setting time buffer pointer.\n");
|
|
timeBuffer = tb_ptr;
|
|
|
|
// Setup wire to send information back to IEW.
|
|
toIEW = timeBuffer->getWire(0);
|
|
|
|
// Setup wire to read data from IEW (for the ROB).
|
|
robInfoFromIEW = timeBuffer->getWire(-iewToCommitDelay);
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::setFetchQueue(TimeBuffer<FetchStruct> *fq_ptr)
|
|
{
|
|
DPRINTF(Commit, "Commit: Setting fetch queue pointer.\n");
|
|
fetchQueue = fq_ptr;
|
|
|
|
// Setup wire to get instructions from rename (for the ROB).
|
|
fromFetch = fetchQueue->getWire(-fetchToCommitDelay);
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::setRenameQueue(TimeBuffer<RenameStruct> *rq_ptr)
|
|
{
|
|
DPRINTF(Commit, "Commit: Setting rename queue pointer.\n");
|
|
renameQueue = rq_ptr;
|
|
|
|
// Setup wire to get instructions from rename (for the ROB).
|
|
fromRename = renameQueue->getWire(-renameToROBDelay);
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::setIEWQueue(TimeBuffer<IEWStruct> *iq_ptr)
|
|
{
|
|
DPRINTF(Commit, "Commit: Setting IEW queue pointer.\n");
|
|
iewQueue = iq_ptr;
|
|
|
|
// Setup wire to get instructions from IEW.
|
|
fromIEW = iewQueue->getWire(-iewToCommitDelay);
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::setFetchStage(Fetch *fetch_stage)
|
|
{
|
|
fetchStage = fetch_stage;
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::setIEWStage(IEW *iew_stage)
|
|
{
|
|
iewStage = iew_stage;
|
|
}
|
|
|
|
template<class Impl>
|
|
void
|
|
DefaultCommit<Impl>::setActiveThreads(list<unsigned> *at_ptr)
|
|
{
|
|
DPRINTF(Commit, "Commit: Setting active threads list pointer.\n");
|
|
activeThreads = at_ptr;
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::setRenameMap(RenameMap rm_ptr[])
|
|
{
|
|
DPRINTF(Commit, "Setting rename map pointers.\n");
|
|
|
|
for (int i=0; i < numThreads; i++) {
|
|
renameMap[i] = &rm_ptr[i];
|
|
}
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::setROB(ROB *rob_ptr)
|
|
{
|
|
DPRINTF(Commit, "Commit: Setting ROB pointer.\n");
|
|
rob = rob_ptr;
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::initStage()
|
|
{
|
|
rob->setActiveThreads(activeThreads);
|
|
rob->resetEntries();
|
|
|
|
// Broadcast the number of free entries.
|
|
for (int i=0; i < numThreads; i++) {
|
|
toIEW->commitInfo[i].usedROB = true;
|
|
toIEW->commitInfo[i].freeROBEntries = rob->numFreeEntries(i);
|
|
}
|
|
|
|
cpu->activityThisCycle();
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::switchOut()
|
|
{
|
|
switchPending = true;
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::doSwitchOut()
|
|
{
|
|
switchedOut = true;
|
|
switchPending = false;
|
|
rob->switchOut();
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::takeOverFrom()
|
|
{
|
|
switchedOut = false;
|
|
_status = Active;
|
|
_nextStatus = Inactive;
|
|
for (int i=0; i < numThreads; i++) {
|
|
commitStatus[i] = Idle;
|
|
changedROBNumEntries[i] = false;
|
|
trapSquash[i] = false;
|
|
xcSquash[i] = false;
|
|
}
|
|
squashCounter = 0;
|
|
rob->takeOverFrom();
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::updateStatus()
|
|
{
|
|
// reset ROB changed variable
|
|
list<unsigned>::iterator threads = (*activeThreads).begin();
|
|
while (threads != (*activeThreads).end()) {
|
|
unsigned tid = *threads++;
|
|
changedROBNumEntries[tid] = false;
|
|
|
|
// Also check if any of the threads has a trap pending
|
|
if (commitStatus[tid] == TrapPending ||
|
|
commitStatus[tid] == FetchTrapPending) {
|
|
_nextStatus = Active;
|
|
}
|
|
}
|
|
|
|
if (_nextStatus == Inactive && _status == Active) {
|
|
DPRINTF(Activity, "Deactivating stage.\n");
|
|
cpu->deactivateStage(FullCPU::CommitIdx);
|
|
} else if (_nextStatus == Active && _status == Inactive) {
|
|
DPRINTF(Activity, "Activating stage.\n");
|
|
cpu->activateStage(FullCPU::CommitIdx);
|
|
}
|
|
|
|
_status = _nextStatus;
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::setNextStatus()
|
|
{
|
|
int squashes = 0;
|
|
|
|
list<unsigned>::iterator threads = (*activeThreads).begin();
|
|
|
|
while (threads != (*activeThreads).end()) {
|
|
unsigned tid = *threads++;
|
|
|
|
if (commitStatus[tid] == ROBSquashing) {
|
|
squashes++;
|
|
}
|
|
}
|
|
|
|
assert(squashes == squashCounter);
|
|
|
|
// If commit is currently squashing, then it will have activity for the
|
|
// next cycle. Set its next status as active.
|
|
if (squashCounter) {
|
|
_nextStatus = Active;
|
|
}
|
|
}
|
|
|
|
template <class Impl>
|
|
bool
|
|
DefaultCommit<Impl>::changedROBEntries()
|
|
{
|
|
list<unsigned>::iterator threads = (*activeThreads).begin();
|
|
|
|
while (threads != (*activeThreads).end()) {
|
|
unsigned tid = *threads++;
|
|
|
|
if (changedROBNumEntries[tid]) {
|
|
return true;
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
template <class Impl>
|
|
unsigned
|
|
DefaultCommit<Impl>::numROBFreeEntries(unsigned tid)
|
|
{
|
|
return rob->numFreeEntries(tid);
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::generateTrapEvent(unsigned tid)
|
|
{
|
|
DPRINTF(Commit, "Generating trap event for [tid:%i]\n", tid);
|
|
|
|
TrapEvent *trap = new TrapEvent(this, tid);
|
|
|
|
trap->schedule(curTick + trapLatency);
|
|
|
|
thread[tid]->trapPending = true;
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::generateXCEvent(unsigned tid)
|
|
{
|
|
DPRINTF(Commit, "Generating XC squash event for [tid:%i]\n", tid);
|
|
|
|
xcSquash[tid] = true;
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::squashAll(unsigned tid)
|
|
{
|
|
// If we want to include the squashing instruction in the squash,
|
|
// then use one older sequence number.
|
|
// Hopefully this doesn't mess things up. Basically I want to squash
|
|
// all instructions of this thread.
|
|
InstSeqNum squashed_inst = rob->isEmpty() ?
|
|
0 : rob->readHeadInst(tid)->seqNum - 1;;
|
|
|
|
// All younger instructions will be squashed. Set the sequence
|
|
// number as the youngest instruction in the ROB (0 in this case.
|
|
// Hopefully nothing breaks.)
|
|
youngestSeqNum[tid] = 0;
|
|
|
|
rob->squash(squashed_inst, tid);
|
|
changedROBNumEntries[tid] = true;
|
|
|
|
// Send back the sequence number of the squashed instruction.
|
|
toIEW->commitInfo[tid].doneSeqNum = squashed_inst;
|
|
|
|
// Send back the squash signal to tell stages that they should
|
|
// squash.
|
|
toIEW->commitInfo[tid].squash = true;
|
|
|
|
// Send back the rob squashing signal so other stages know that
|
|
// the ROB is in the process of squashing.
|
|
toIEW->commitInfo[tid].robSquashing = true;
|
|
|
|
toIEW->commitInfo[tid].branchMispredict = false;
|
|
|
|
toIEW->commitInfo[tid].nextPC = PC[tid];
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::squashFromTrap(unsigned tid)
|
|
{
|
|
squashAll(tid);
|
|
|
|
DPRINTF(Commit, "Squashing from trap, restarting at PC %#x\n", PC[tid]);
|
|
|
|
thread[tid]->trapPending = false;
|
|
thread[tid]->inSyscall = false;
|
|
|
|
trapSquash[tid] = false;
|
|
|
|
commitStatus[tid] = ROBSquashing;
|
|
cpu->activityThisCycle();
|
|
|
|
++squashCounter;
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::squashFromXC(unsigned tid)
|
|
{
|
|
squashAll(tid);
|
|
|
|
DPRINTF(Commit, "Squashing from XC, restarting at PC %#x\n", PC[tid]);
|
|
|
|
thread[tid]->inSyscall = false;
|
|
assert(!thread[tid]->trapPending);
|
|
|
|
commitStatus[tid] = ROBSquashing;
|
|
cpu->activityThisCycle();
|
|
|
|
xcSquash[tid] = false;
|
|
|
|
++squashCounter;
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::tick()
|
|
{
|
|
wroteToTimeBuffer = false;
|
|
_nextStatus = Inactive;
|
|
|
|
if (switchPending && rob->isEmpty() && !iewStage->hasStoresToWB()) {
|
|
cpu->signalSwitched();
|
|
return;
|
|
}
|
|
|
|
list<unsigned>::iterator threads = (*activeThreads).begin();
|
|
|
|
// Check if any of the threads are done squashing. Change the
|
|
// status if they are done.
|
|
while (threads != (*activeThreads).end()) {
|
|
unsigned tid = *threads++;
|
|
|
|
if (commitStatus[tid] == ROBSquashing) {
|
|
|
|
if (rob->isDoneSquashing(tid)) {
|
|
commitStatus[tid] = Running;
|
|
--squashCounter;
|
|
} else {
|
|
DPRINTF(Commit,"[tid:%u]: Still Squashing, cannot commit any"
|
|
"insts this cycle.\n", tid);
|
|
}
|
|
}
|
|
}
|
|
|
|
commit();
|
|
|
|
markCompletedInsts();
|
|
|
|
threads = (*activeThreads).begin();
|
|
|
|
while (threads != (*activeThreads).end()) {
|
|
unsigned tid = *threads++;
|
|
|
|
if (!rob->isEmpty(tid) && rob->readHeadInst(tid)->readyToCommit()) {
|
|
// The ROB has more instructions it can commit. Its next status
|
|
// will be active.
|
|
_nextStatus = Active;
|
|
|
|
DynInstPtr inst = rob->readHeadInst(tid);
|
|
|
|
DPRINTF(Commit,"[tid:%i]: Instruction [sn:%lli] PC %#x is head of"
|
|
" ROB and ready to commit\n",
|
|
tid, inst->seqNum, inst->readPC());
|
|
|
|
} else if (!rob->isEmpty(tid)) {
|
|
DynInstPtr inst = rob->readHeadInst(tid);
|
|
|
|
DPRINTF(Commit,"[tid:%i]: Can't commit, Instruction [sn:%lli] PC "
|
|
"%#x is head of ROB and not ready\n",
|
|
tid, inst->seqNum, inst->readPC());
|
|
}
|
|
|
|
DPRINTF(Commit, "[tid:%i]: ROB has %d insts & %d free entries.\n",
|
|
tid, rob->countInsts(tid), rob->numFreeEntries(tid));
|
|
}
|
|
|
|
|
|
if (wroteToTimeBuffer) {
|
|
DPRINTF(Activity, "Activity This Cycle.\n");
|
|
cpu->activityThisCycle();
|
|
}
|
|
|
|
updateStatus();
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::commit()
|
|
{
|
|
|
|
//////////////////////////////////////
|
|
// Check for interrupts
|
|
//////////////////////////////////////
|
|
|
|
#if FULL_SYSTEM
|
|
// Process interrupts if interrupts are enabled, not in PAL mode,
|
|
// and no other traps or external squashes are currently pending.
|
|
// @todo: Allow other threads to handle interrupts.
|
|
if (cpu->checkInterrupts &&
|
|
cpu->check_interrupts() &&
|
|
!cpu->inPalMode(readPC()) &&
|
|
!trapSquash[0] &&
|
|
!xcSquash[0]) {
|
|
// Tell fetch that there is an interrupt pending. This will
|
|
// make fetch wait until it sees a non PAL-mode PC, at which
|
|
// point it stops fetching instructions.
|
|
toIEW->commitInfo[0].interruptPending = true;
|
|
|
|
// Wait until the ROB is empty and all stores have drained in
|
|
// order to enter the interrupt.
|
|
if (rob->isEmpty() && !iewStage->hasStoresToWB()) {
|
|
// Not sure which thread should be the one to interrupt. For now
|
|
// always do thread 0.
|
|
assert(!thread[0]->inSyscall);
|
|
thread[0]->inSyscall = true;
|
|
|
|
// CPU will handle implementation of the interrupt.
|
|
cpu->processInterrupts();
|
|
|
|
// Now squash or record that I need to squash this cycle.
|
|
commitStatus[0] = TrapPending;
|
|
|
|
// Exit state update mode to avoid accidental updating.
|
|
thread[0]->inSyscall = false;
|
|
|
|
// Generate trap squash event.
|
|
generateTrapEvent(0);
|
|
|
|
toIEW->commitInfo[0].clearInterrupt = true;
|
|
|
|
DPRINTF(Commit, "Interrupt detected.\n");
|
|
} else {
|
|
DPRINTF(Commit, "Interrupt pending, waiting for ROB to empty.\n");
|
|
}
|
|
}
|
|
#endif // FULL_SYSTEM
|
|
|
|
////////////////////////////////////
|
|
// Check for any possible squashes, handle them first
|
|
////////////////////////////////////
|
|
|
|
list<unsigned>::iterator threads = (*activeThreads).begin();
|
|
|
|
while (threads != (*activeThreads).end()) {
|
|
unsigned tid = *threads++;
|
|
|
|
if (fromFetch->fetchFault && commitStatus[0] != TrapPending) {
|
|
// Record the fault. Wait until it's empty in the ROB.
|
|
// Then handle the trap. Ignore it if there's already a
|
|
// trap pending as fetch will be redirected.
|
|
fetchFault = fromFetch->fetchFault;
|
|
fetchFaultTick = curTick + fetchTrapLatency;
|
|
commitStatus[0] = FetchTrapPending;
|
|
DPRINTF(Commit, "Fault from fetch recorded. Will trap if the "
|
|
"ROB empties without squashing the fault.\n");
|
|
fetchTrapWait = 0;
|
|
}
|
|
|
|
// Fetch may tell commit to clear the trap if it's been squashed.
|
|
if (fromFetch->clearFetchFault) {
|
|
DPRINTF(Commit, "Received clear fetch fault signal\n");
|
|
fetchTrapWait = 0;
|
|
if (commitStatus[0] == FetchTrapPending) {
|
|
DPRINTF(Commit, "Clearing fault from fetch\n");
|
|
commitStatus[0] = Running;
|
|
}
|
|
}
|
|
|
|
// Not sure which one takes priority. I think if we have
|
|
// both, that's a bad sign.
|
|
if (trapSquash[tid] == true) {
|
|
assert(!xcSquash[tid]);
|
|
squashFromTrap(tid);
|
|
} else if (xcSquash[tid] == true) {
|
|
squashFromXC(tid);
|
|
}
|
|
|
|
// Squashed sequence number must be older than youngest valid
|
|
// instruction in the ROB. This prevents squashes from younger
|
|
// instructions overriding squashes from older instructions.
|
|
if (fromIEW->squash[tid] &&
|
|
commitStatus[tid] != TrapPending &&
|
|
fromIEW->squashedSeqNum[tid] <= youngestSeqNum[tid]) {
|
|
|
|
DPRINTF(Commit, "[tid:%i]: Squashing due to PC %#x [sn:%i]\n",
|
|
tid,
|
|
fromIEW->mispredPC[tid],
|
|
fromIEW->squashedSeqNum[tid]);
|
|
|
|
DPRINTF(Commit, "[tid:%i]: Redirecting to PC %#x\n",
|
|
tid,
|
|
fromIEW->nextPC[tid]);
|
|
|
|
commitStatus[tid] = ROBSquashing;
|
|
|
|
++squashCounter;
|
|
|
|
// If we want to include the squashing instruction in the squash,
|
|
// then use one older sequence number.
|
|
InstSeqNum squashed_inst = fromIEW->squashedSeqNum[tid];
|
|
|
|
if (fromIEW->includeSquashInst[tid] == true)
|
|
squashed_inst--;
|
|
|
|
// All younger instructions will be squashed. Set the sequence
|
|
// number as the youngest instruction in the ROB.
|
|
youngestSeqNum[tid] = squashed_inst;
|
|
|
|
rob->squash(squashed_inst, tid);
|
|
changedROBNumEntries[tid] = true;
|
|
|
|
toIEW->commitInfo[tid].doneSeqNum = squashed_inst;
|
|
|
|
toIEW->commitInfo[tid].squash = true;
|
|
|
|
// Send back the rob squashing signal so other stages know that
|
|
// the ROB is in the process of squashing.
|
|
toIEW->commitInfo[tid].robSquashing = true;
|
|
|
|
toIEW->commitInfo[tid].branchMispredict =
|
|
fromIEW->branchMispredict[tid];
|
|
|
|
toIEW->commitInfo[tid].branchTaken =
|
|
fromIEW->branchTaken[tid];
|
|
|
|
toIEW->commitInfo[tid].nextPC = fromIEW->nextPC[tid];
|
|
|
|
toIEW->commitInfo[tid].mispredPC = fromIEW->mispredPC[tid];
|
|
|
|
if (toIEW->commitInfo[tid].branchMispredict) {
|
|
++branchMispredicts;
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
setNextStatus();
|
|
|
|
if (squashCounter != numThreads) {
|
|
// If we're not currently squashing, then get instructions.
|
|
getInsts();
|
|
|
|
// Try to commit any instructions.
|
|
commitInsts();
|
|
}
|
|
|
|
//Check for any activity
|
|
threads = (*activeThreads).begin();
|
|
|
|
while (threads != (*activeThreads).end()) {
|
|
unsigned tid = *threads++;
|
|
|
|
if (changedROBNumEntries[tid]) {
|
|
toIEW->commitInfo[tid].usedROB = true;
|
|
toIEW->commitInfo[tid].freeROBEntries = rob->numFreeEntries(tid);
|
|
|
|
if (rob->isEmpty(tid)) {
|
|
toIEW->commitInfo[tid].emptyROB = true;
|
|
}
|
|
|
|
wroteToTimeBuffer = true;
|
|
changedROBNumEntries[tid] = false;
|
|
}
|
|
}
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::commitInsts()
|
|
{
|
|
////////////////////////////////////
|
|
// Handle commit
|
|
// Note that commit will be handled prior to putting new
|
|
// instructions in the ROB so that the ROB only tries to commit
|
|
// instructions it has in this current cycle, and not instructions
|
|
// it is writing in during this cycle. Can't commit and squash
|
|
// things at the same time...
|
|
////////////////////////////////////
|
|
|
|
DPRINTF(Commit, "Trying to commit instructions in the ROB.\n");
|
|
|
|
unsigned num_committed = 0;
|
|
|
|
DynInstPtr head_inst;
|
|
#if FULL_SYSTEM
|
|
// Not the best way to check if the front end is empty, but it should
|
|
// work.
|
|
// @todo: Try to avoid directly accessing fetch.
|
|
if (commitStatus[0] == FetchTrapPending && rob->isEmpty()) {
|
|
DPRINTF(Commit, "Fault from fetch is pending.\n");
|
|
|
|
fetchTrapWait++;
|
|
if (fetchTrapWait > 10000000) {
|
|
panic("Fetch trap has been pending for a long time!");
|
|
}
|
|
if (fetchFaultTick > curTick) {
|
|
DPRINTF(Commit, "Not enough cycles since fault, fault will "
|
|
"happen on %lli\n",
|
|
fetchFaultTick);
|
|
cpu->activityThisCycle();
|
|
return;
|
|
} else if (iewStage->hasStoresToWB()) {
|
|
DPRINTF(Commit, "IEW still has stores to WB. Waiting until "
|
|
"they are completed. fetchTrapWait:%i\n",
|
|
fetchTrapWait);
|
|
cpu->activityThisCycle();
|
|
return;
|
|
} else if (cpu->inPalMode(readPC())) {
|
|
DPRINTF(Commit, "In pal mode right now. fetchTrapWait:%i\n",
|
|
fetchTrapWait);
|
|
return;
|
|
} else if (fetchStage->getYoungestSN() > youngestSeqNum[0]) {
|
|
DPRINTF(Commit, "Waiting for front end to drain. fetchTrapWait:%i\n",
|
|
fetchTrapWait);
|
|
return;
|
|
}
|
|
fetchTrapWait = 0;
|
|
DPRINTF(Commit, "ROB is empty, handling fetch trap.\n");
|
|
|
|
assert(!thread[0]->inSyscall);
|
|
|
|
thread[0]->inSyscall = true;
|
|
|
|
// Consider holding onto the trap and waiting until the trap event
|
|
// happens for this to be executed.
|
|
cpu->trap(fetchFault, 0);
|
|
|
|
// Exit state update mode to avoid accidental updating.
|
|
thread[0]->inSyscall = false;
|
|
|
|
commitStatus[0] = TrapPending;
|
|
// Set it up so that we squash next cycle
|
|
trapSquash[0] = true;
|
|
return;
|
|
}
|
|
#endif
|
|
|
|
// Commit as many instructions as possible until the commit bandwidth
|
|
// limit is reached, or it becomes impossible to commit any more.
|
|
while (num_committed < commitWidth) {
|
|
int commit_thread = getCommittingThread();
|
|
|
|
if (commit_thread == -1 || !rob->isHeadReady(commit_thread))
|
|
break;
|
|
|
|
head_inst = rob->readHeadInst(commit_thread);
|
|
|
|
int tid = head_inst->threadNumber;
|
|
|
|
assert(tid == commit_thread);
|
|
|
|
DPRINTF(Commit, "Trying to commit head instruction, [sn:%i] [tid:%i]\n",
|
|
head_inst->seqNum, tid);
|
|
|
|
// If the head instruction is squashed, it is ready to retire
|
|
// (be removed from the ROB) at any time.
|
|
if (head_inst->isSquashed()) {
|
|
|
|
DPRINTF(Commit, "Retiring squashed instruction from "
|
|
"ROB.\n");
|
|
|
|
rob->retireHead(commit_thread);
|
|
|
|
++commitSquashedInsts;
|
|
|
|
// Record that the number of ROB entries has changed.
|
|
changedROBNumEntries[tid] = true;
|
|
} else {
|
|
PC[tid] = head_inst->readPC();
|
|
nextPC[tid] = head_inst->readNextPC();
|
|
|
|
// Increment the total number of non-speculative instructions
|
|
// executed.
|
|
// Hack for now: it really shouldn't happen until after the
|
|
// commit is deemed to be successful, but this count is needed
|
|
// for syscalls.
|
|
thread[tid]->funcExeInst++;
|
|
|
|
// Try to commit the head instruction.
|
|
bool commit_success = commitHead(head_inst, num_committed);
|
|
|
|
if (commit_success) {
|
|
++num_committed;
|
|
|
|
changedROBNumEntries[tid] = true;
|
|
|
|
// Set the doneSeqNum to the youngest committed instruction.
|
|
toIEW->commitInfo[tid].doneSeqNum = head_inst->seqNum;
|
|
|
|
++commitCommittedInsts;
|
|
|
|
// To match the old model, don't count nops and instruction
|
|
// prefetches towards the total commit count.
|
|
if (!head_inst->isNop() && !head_inst->isInstPrefetch()) {
|
|
cpu->instDone(tid);
|
|
}
|
|
|
|
PC[tid] = nextPC[tid];
|
|
nextPC[tid] = nextPC[tid] + sizeof(TheISA::MachInst);
|
|
#if FULL_SYSTEM
|
|
int count = 0;
|
|
Addr oldpc;
|
|
do {
|
|
// Debug statement. Checks to make sure we're not
|
|
// currently updating state while handling PC events.
|
|
if (count == 0)
|
|
assert(!thread[tid]->inSyscall &&
|
|
!thread[tid]->trapPending);
|
|
oldpc = PC[tid];
|
|
cpu->system->pcEventQueue.service(
|
|
thread[tid]->getXCProxy());
|
|
count++;
|
|
} while (oldpc != PC[tid]);
|
|
if (count > 1) {
|
|
DPRINTF(Commit, "PC skip function event, stopping commit\n");
|
|
break;
|
|
}
|
|
#endif
|
|
} else {
|
|
DPRINTF(Commit, "Unable to commit head instruction PC:%#x "
|
|
"[tid:%i] [sn:%i].\n",
|
|
head_inst->readPC(), tid ,head_inst->seqNum);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
DPRINTF(CommitRate, "%i\n", num_committed);
|
|
numCommittedDist.sample(num_committed);
|
|
|
|
if (num_committed == commitWidth) {
|
|
commitEligible[0]++;
|
|
}
|
|
}
|
|
|
|
template <class Impl>
|
|
bool
|
|
DefaultCommit<Impl>::commitHead(DynInstPtr &head_inst, unsigned inst_num)
|
|
{
|
|
assert(head_inst);
|
|
|
|
int tid = head_inst->threadNumber;
|
|
|
|
// If the instruction is not executed yet, then it will need extra
|
|
// handling. Signal backwards that it should be executed.
|
|
if (!head_inst->isExecuted()) {
|
|
// Keep this number correct. We have not yet actually executed
|
|
// and committed this instruction.
|
|
thread[tid]->funcExeInst--;
|
|
|
|
head_inst->reachedCommit = true;
|
|
|
|
if (head_inst->isNonSpeculative() ||
|
|
head_inst->isMemBarrier() ||
|
|
head_inst->isWriteBarrier()) {
|
|
|
|
DPRINTF(Commit, "Encountered a barrier or non-speculative "
|
|
"instruction [sn:%lli] at the head of the ROB, PC %#x.\n",
|
|
head_inst->seqNum, head_inst->readPC());
|
|
|
|
#if !FULL_SYSTEM
|
|
// Hack to make sure syscalls/memory barriers/quiesces
|
|
// aren't executed until all stores write back their data.
|
|
// This direct communication shouldn't be used for
|
|
// anything other than this.
|
|
if (inst_num > 0 || iewStage->hasStoresToWB())
|
|
#else
|
|
if ((head_inst->isMemBarrier() || head_inst->isWriteBarrier() ||
|
|
head_inst->isQuiesce()) &&
|
|
iewStage->hasStoresToWB())
|
|
#endif
|
|
{
|
|
DPRINTF(Commit, "Waiting for all stores to writeback.\n");
|
|
return false;
|
|
}
|
|
|
|
toIEW->commitInfo[tid].nonSpecSeqNum = head_inst->seqNum;
|
|
|
|
// Change the instruction so it won't try to commit again until
|
|
// it is executed.
|
|
head_inst->clearCanCommit();
|
|
|
|
++commitNonSpecStalls;
|
|
|
|
return false;
|
|
} else if (head_inst->isLoad()) {
|
|
DPRINTF(Commit, "[sn:%lli]: Uncached load, PC %#x.\n",
|
|
head_inst->seqNum, head_inst->readPC());
|
|
|
|
// Send back the non-speculative instruction's sequence
|
|
// number. Tell the lsq to re-execute the load.
|
|
toIEW->commitInfo[tid].nonSpecSeqNum = head_inst->seqNum;
|
|
toIEW->commitInfo[tid].uncached = true;
|
|
toIEW->commitInfo[tid].uncachedLoad = head_inst;
|
|
|
|
head_inst->clearCanCommit();
|
|
|
|
return false;
|
|
} else {
|
|
panic("Trying to commit un-executed instruction "
|
|
"of unknown type!\n");
|
|
}
|
|
}
|
|
|
|
if (head_inst->isThreadSync()) {
|
|
// Not handled for now.
|
|
panic("Thread sync instructions are not handled yet.\n");
|
|
}
|
|
|
|
// Stores mark themselves as completed.
|
|
if (!head_inst->isStore()) {
|
|
head_inst->setCompleted();
|
|
}
|
|
|
|
// Use checker prior to updating anything due to traps or PC
|
|
// based events.
|
|
if (cpu->checker) {
|
|
cpu->checker->tick(head_inst);
|
|
}
|
|
|
|
// Check if the instruction caused a fault. If so, trap.
|
|
Fault inst_fault = head_inst->getFault();
|
|
|
|
if (inst_fault != NoFault) {
|
|
head_inst->setCompleted();
|
|
#if FULL_SYSTEM
|
|
DPRINTF(Commit, "Inst [sn:%lli] PC %#x has a fault\n",
|
|
head_inst->seqNum, head_inst->readPC());
|
|
|
|
if (iewStage->hasStoresToWB() || inst_num > 0) {
|
|
DPRINTF(Commit, "Stores outstanding, fault must wait.\n");
|
|
return false;
|
|
}
|
|
|
|
if (cpu->checker && head_inst->isStore()) {
|
|
cpu->checker->tick(head_inst);
|
|
}
|
|
|
|
assert(!thread[tid]->inSyscall);
|
|
|
|
// Mark that we're in state update mode so that the trap's
|
|
// execution doesn't generate extra squashes.
|
|
thread[tid]->inSyscall = true;
|
|
|
|
// DTB will sometimes need the machine instruction for when
|
|
// faults happen. So we will set it here, prior to the DTB
|
|
// possibly needing it for its fault.
|
|
thread[tid]->setInst(
|
|
static_cast<TheISA::MachInst>(head_inst->staticInst->machInst));
|
|
|
|
// Execute the trap. Although it's slightly unrealistic in
|
|
// terms of timing (as it doesn't wait for the full timing of
|
|
// the trap event to complete before updating state), it's
|
|
// needed to update the state as soon as possible. This
|
|
// prevents external agents from changing any specific state
|
|
// that the trap need.
|
|
cpu->trap(inst_fault, tid);
|
|
|
|
// Exit state update mode to avoid accidental updating.
|
|
thread[tid]->inSyscall = false;
|
|
|
|
commitStatus[tid] = TrapPending;
|
|
|
|
// Generate trap squash event.
|
|
generateTrapEvent(tid);
|
|
|
|
return false;
|
|
#else // !FULL_SYSTEM
|
|
panic("fault (%d) detected @ PC %08p", inst_fault,
|
|
head_inst->PC);
|
|
#endif // FULL_SYSTEM
|
|
}
|
|
|
|
updateComInstStats(head_inst);
|
|
|
|
if (head_inst->traceData) {
|
|
head_inst->traceData->setFetchSeq(head_inst->seqNum);
|
|
head_inst->traceData->setCPSeq(thread[tid]->numInst);
|
|
head_inst->traceData->finalize();
|
|
head_inst->traceData = NULL;
|
|
}
|
|
|
|
// Update the commit rename map
|
|
for (int i = 0; i < head_inst->numDestRegs(); i++) {
|
|
renameMap[tid]->setEntry(head_inst->destRegIdx(i),
|
|
head_inst->renamedDestRegIdx(i));
|
|
}
|
|
|
|
// Finally clear the head ROB entry.
|
|
rob->retireHead(tid);
|
|
|
|
// Return true to indicate that we have committed an instruction.
|
|
return true;
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::getInsts()
|
|
{
|
|
// Read any renamed instructions and place them into the ROB.
|
|
int insts_to_process = min((int)renameWidth, fromRename->size);
|
|
|
|
for (int inst_num = 0; inst_num < insts_to_process; ++inst_num)
|
|
{
|
|
DynInstPtr inst = fromRename->insts[inst_num];
|
|
int tid = inst->threadNumber;
|
|
|
|
if (!inst->isSquashed() &&
|
|
commitStatus[tid] != ROBSquashing) {
|
|
changedROBNumEntries[tid] = true;
|
|
|
|
DPRINTF(Commit, "Inserting PC %#x [sn:%i] [tid:%i] into ROB.\n",
|
|
inst->readPC(), inst->seqNum, tid);
|
|
|
|
rob->insertInst(inst);
|
|
|
|
assert(rob->getThreadEntries(tid) <= rob->getMaxEntries(tid));
|
|
|
|
youngestSeqNum[tid] = inst->seqNum;
|
|
} else {
|
|
DPRINTF(Commit, "Instruction PC %#x [sn:%i] [tid:%i] was "
|
|
"squashed, skipping.\n",
|
|
inst->readPC(), inst->seqNum, tid);
|
|
}
|
|
}
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::markCompletedInsts()
|
|
{
|
|
// Grab completed insts out of the IEW instruction queue, and mark
|
|
// instructions completed within the ROB.
|
|
for (int inst_num = 0;
|
|
inst_num < fromIEW->size && fromIEW->insts[inst_num];
|
|
++inst_num)
|
|
{
|
|
if (!fromIEW->insts[inst_num]->isSquashed()) {
|
|
DPRINTF(Commit, "[tid:%i]: Marking PC %#x, [sn:%lli] ready "
|
|
"within ROB.\n",
|
|
fromIEW->insts[inst_num]->threadNumber,
|
|
fromIEW->insts[inst_num]->readPC(),
|
|
fromIEW->insts[inst_num]->seqNum);
|
|
|
|
// Mark the instruction as ready to commit.
|
|
fromIEW->insts[inst_num]->setCanCommit();
|
|
}
|
|
}
|
|
}
|
|
|
|
template <class Impl>
|
|
bool
|
|
DefaultCommit<Impl>::robDoneSquashing()
|
|
{
|
|
list<unsigned>::iterator threads = (*activeThreads).begin();
|
|
|
|
while (threads != (*activeThreads).end()) {
|
|
unsigned tid = *threads++;
|
|
|
|
if (!rob->isDoneSquashing(tid))
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
template <class Impl>
|
|
void
|
|
DefaultCommit<Impl>::updateComInstStats(DynInstPtr &inst)
|
|
{
|
|
unsigned thread = inst->threadNumber;
|
|
|
|
//
|
|
// Pick off the software prefetches
|
|
//
|
|
#ifdef TARGET_ALPHA
|
|
if (inst->isDataPrefetch()) {
|
|
statComSwp[thread]++;
|
|
} else {
|
|
statComInst[thread]++;
|
|
}
|
|
#else
|
|
statComInst[thread]++;
|
|
#endif
|
|
|
|
//
|
|
// Control Instructions
|
|
//
|
|
if (inst->isControl())
|
|
statComBranches[thread]++;
|
|
|
|
//
|
|
// Memory references
|
|
//
|
|
if (inst->isMemRef()) {
|
|
statComRefs[thread]++;
|
|
|
|
if (inst->isLoad()) {
|
|
statComLoads[thread]++;
|
|
}
|
|
}
|
|
|
|
if (inst->isMemBarrier()) {
|
|
statComMembars[thread]++;
|
|
}
|
|
}
|
|
|
|
////////////////////////////////////////
|
|
// //
|
|
// SMT COMMIT POLICY MAINTAINED HERE //
|
|
// //
|
|
////////////////////////////////////////
|
|
template <class Impl>
|
|
int
|
|
DefaultCommit<Impl>::getCommittingThread()
|
|
{
|
|
if (numThreads > 1) {
|
|
switch (commitPolicy) {
|
|
|
|
case Aggressive:
|
|
//If Policy is Aggressive, commit will call
|
|
//this function multiple times per
|
|
//cycle
|
|
return oldestReady();
|
|
|
|
case RoundRobin:
|
|
return roundRobin();
|
|
|
|
case OldestReady:
|
|
return oldestReady();
|
|
|
|
default:
|
|
return -1;
|
|
}
|
|
} else {
|
|
int tid = (*activeThreads).front();
|
|
|
|
if (commitStatus[tid] == Running ||
|
|
commitStatus[tid] == Idle ||
|
|
commitStatus[tid] == FetchTrapPending) {
|
|
return tid;
|
|
} else {
|
|
return -1;
|
|
}
|
|
}
|
|
}
|
|
|
|
template<class Impl>
|
|
int
|
|
DefaultCommit<Impl>::roundRobin()
|
|
{
|
|
list<unsigned>::iterator pri_iter = priority_list.begin();
|
|
list<unsigned>::iterator end = priority_list.end();
|
|
|
|
while (pri_iter != end) {
|
|
unsigned tid = *pri_iter;
|
|
|
|
if (commitStatus[tid] == Running ||
|
|
commitStatus[tid] == Idle) {
|
|
|
|
if (rob->isHeadReady(tid)) {
|
|
priority_list.erase(pri_iter);
|
|
priority_list.push_back(tid);
|
|
|
|
return tid;
|
|
}
|
|
}
|
|
|
|
pri_iter++;
|
|
}
|
|
|
|
return -1;
|
|
}
|
|
|
|
template<class Impl>
|
|
int
|
|
DefaultCommit<Impl>::oldestReady()
|
|
{
|
|
unsigned oldest = 0;
|
|
bool first = true;
|
|
|
|
list<unsigned>::iterator threads = (*activeThreads).begin();
|
|
|
|
while (threads != (*activeThreads).end()) {
|
|
unsigned tid = *threads++;
|
|
|
|
if (!rob->isEmpty(tid) &&
|
|
(commitStatus[tid] == Running ||
|
|
commitStatus[tid] == Idle ||
|
|
commitStatus[tid] == FetchTrapPending)) {
|
|
|
|
if (rob->isHeadReady(tid)) {
|
|
|
|
DynInstPtr head_inst = rob->readHeadInst(tid);
|
|
|
|
if (first) {
|
|
oldest = tid;
|
|
first = false;
|
|
} else if (head_inst->seqNum < oldest) {
|
|
oldest = tid;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if (!first) {
|
|
return oldest;
|
|
} else {
|
|
return -1;
|
|
}
|
|
}
|