gem5/src/cpu/inorder/resource.cc
Korey Sewell 078f914e69 inorder: SE mode TLB faults
handle them like we do in FS mode, by blocking the TLB until the fault
is handled by the fault->invoke()
2011-06-19 21:43:42 -04:00

529 lines
13 KiB
C++

/*
* Copyright (c) 2007 MIPS Technologies, Inc.
* 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.
*
* Authors: Korey Sewell
*
*/
#include <list>
#include <vector>
#include "base/str.hh"
#include "cpu/inorder/cpu.hh"
#include "cpu/inorder/resource.hh"
#include "cpu/inorder/resource_pool.hh"
#include "debug/ExecFaulting.hh"
#include "debug/RefCount.hh"
#include "debug/ResReqCount.hh"
#include "debug/Resource.hh"
using namespace std;
Resource::Resource(string res_name, int res_id, int res_width,
int res_latency, InOrderCPU *_cpu)
: resName(res_name), id(res_id),
width(res_width), latency(res_latency), cpu(_cpu),
resourceEvent(NULL)
{
reqs.resize(width);
// Use to deny a instruction a resource.
deniedReq = new ResourceRequest(this);
deniedReq->valid = true;
}
Resource::~Resource()
{
if (resourceEvent) {
delete [] resourceEvent;
}
delete deniedReq;
for (int i = 0; i < width; i++) {
delete reqs[i];
}
}
void
Resource::init()
{
// If the resource has a zero-cycle (no latency)
// function, then no reason to have events
// that will process them for the right tick
if (latency > 0)
resourceEvent = new ResourceEvent[width];
for (int i = 0; i < width; i++)
reqs[i] = new ResourceRequest(this);
initSlots();
}
void
Resource::initSlots()
{
// Add available slot numbers for resource
for (int slot_idx = 0; slot_idx < width; slot_idx++) {
availSlots.push_back(slot_idx);
if (resourceEvent) {
resourceEvent[slot_idx].init(this, slot_idx);
}
}
}
std::string
Resource::name()
{
return cpu->name() + "." + resName;
}
int
Resource::slotsAvail()
{
return availSlots.size();
}
int
Resource::slotsInUse()
{
return width - availSlots.size();
}
void
Resource::freeSlot(int slot_idx)
{
DPRINTF(Resource, "Deallocating [slot:%i].\n",
slot_idx);
// Put slot number on this resource's free list
availSlots.push_back(slot_idx);
// Invalidate Request & Reset it's flags
reqs[slot_idx]->clearRequest();
}
int
Resource::findSlot(DynInstPtr inst)
{
int slot_num = -1;
for (int i = 0; i < width; i++) {
if (reqs[i]->valid &&
reqs[i]->getInst()->seqNum == inst->seqNum) {
slot_num = reqs[i]->getSlot();
}
}
return slot_num;
}
int
Resource::getSlot(DynInstPtr inst)
{
int slot_num = -1;
if (slotsAvail() != 0) {
slot_num = availSlots[0];
vector<int>::iterator vect_it = availSlots.begin();
assert(slot_num == *vect_it);
availSlots.erase(vect_it);
}
return slot_num;
}
ResReqPtr
Resource::request(DynInstPtr inst)
{
// See if the resource is already serving this instruction.
// If so, use that request;
bool try_request = false;
int slot_num = -1;
int stage_num;
ResReqPtr inst_req = findRequest(inst);
if (inst_req) {
// If some preprocessing has to be done on instruction
// that has already requested once, then handle it here.
// update the 'try_request' variable if we should
// re-execute the request.
requestAgain(inst, try_request);
slot_num = inst_req->getSlot();
stage_num = inst_req->getStageNum();
} else {
// Get new slot # for instruction
slot_num = getSlot(inst);
if (slot_num != -1) {
DPRINTF(Resource, "Allocating [slot:%i] for [tid:%i]: [sn:%i]\n",
slot_num, inst->readTid(), inst->seqNum);
// Get Stage # from Schedule Entry
stage_num = inst->curSkedEntry->stageNum;
unsigned cmd = inst->curSkedEntry->cmd;
// Generate Resource Request
inst_req = getRequest(inst, stage_num, id, slot_num, cmd);
if (inst->staticInst) {
DPRINTF(Resource, "[tid:%i]: [sn:%i] requesting this "
"resource.\n",
inst->readTid(), inst->seqNum);
} else {
DPRINTF(Resource, "[tid:%i]: instruction requesting this "
"resource.\n",
inst->readTid());
}
try_request = true;
} else {
DPRINTF(Resource, "No slot available for [tid:%i]: [sn:%i]\n",
inst->readTid(), inst->seqNum);
}
}
if (try_request) {
// Schedule execution of resource
scheduleExecution(slot_num);
} else {
inst_req = deniedReq;
rejectRequest(inst);
}
return inst_req;
}
void
Resource::requestAgain(DynInstPtr inst, bool &do_request)
{
do_request = true;
if (inst->staticInst) {
DPRINTF(Resource, "[tid:%i]: [sn:%i] requesting this resource "
"again.\n",
inst->readTid(), inst->seqNum);
} else {
DPRINTF(Resource, "[tid:%i]: requesting this resource again.\n",
inst->readTid());
}
}
ResReqPtr
Resource::getRequest(DynInstPtr inst, int stage_num, int res_idx,
int slot_num, unsigned cmd)
{
reqs[slot_num]->setRequest(inst, stage_num, id, slot_num, cmd);
return reqs[slot_num];
}
ResReqPtr
Resource::findRequest(DynInstPtr inst)
{
for (int i = 0; i < width; i++) {
if (reqs[i]->valid &&
reqs[i]->getInst() == inst) {
return reqs[i];
}
}
return NULL;
}
void
Resource::rejectRequest(DynInstPtr inst)
{
DPRINTF(RefCount, "[tid:%i]: Unable to grant request for [sn:%i].\n",
inst->readTid(), inst->seqNum);
}
void
Resource::execute(int slot_idx)
{
//@todo: have each resource print out command their executing
DPRINTF(Resource, "[tid:%i]: Executing %s resource.\n",
reqs[slot_idx]->getTid(), name());
reqs[slot_idx]->setCompleted(true);
reqs[slot_idx]->done();
}
void
Resource::deactivateThread(ThreadID tid)
{
// In the most basic case, deactivation means squashing everything
// from a particular thread
DynInstPtr dummy_inst = new InOrderDynInst(cpu, NULL, 0, tid, tid);
squash(dummy_inst, 0, 0, tid);
}
void
Resource::setupSquash(DynInstPtr inst, int stage_num, ThreadID tid)
{
// Squash In Pipeline Stage
cpu->pipelineStage[stage_num]->setupSquash(inst, tid);
// Schedule Squash Through-out Resource Pool
cpu->resPool->scheduleEvent(
(InOrderCPU::CPUEventType)ResourcePool::SquashAll, inst, 0);
}
void
Resource::squash(DynInstPtr inst, int stage_num, InstSeqNum squash_seq_num,
ThreadID tid)
{
//@todo: check squash seq num before squashing. can save time going
// through this function.
for (int i = 0; i < width; i++) {
ResReqPtr req_ptr = reqs[i];
DynInstPtr inst = req_ptr->getInst();
if (req_ptr->valid &&
inst->readTid() == tid &&
inst->seqNum > squash_seq_num) {
DPRINTF(Resource, "[tid:%i]: Squashing [sn:%i].\n",
req_ptr->getInst()->readTid(),
req_ptr->getInst()->seqNum);
req_ptr->setSquashed();
int req_slot_num = req_ptr->getSlot();
if (latency > 0) {
if (resourceEvent[req_slot_num].scheduled())
unscheduleEvent(req_slot_num);
}
freeSlot(req_slot_num);
}
}
}
void
Resource::squashDueToMemStall(DynInstPtr inst, int stage_num,
InstSeqNum squash_seq_num,
ThreadID tid)
{
squash(inst, stage_num, squash_seq_num, tid);
}
void
Resource::squashThenTrap(int stage_num, DynInstPtr inst)
{
ThreadID tid = inst->readTid();
inst->setSquashInfo(stage_num);
setupSquash(inst, stage_num, tid);
if (inst->traceData) {
if (inst->staticInst &&
inst->fault != NoFault && DTRACE(ExecFaulting)) {
inst->traceData->setStageCycle(stage_num, curTick());
inst->traceData->setFetchSeq(inst->seqNum);
inst->traceData->dump();
}
delete inst->traceData;
inst->traceData = NULL;
}
cpu->trapContext(inst->fault, tid, inst);
}
Tick
Resource::ticks(int num_cycles)
{
return cpu->ticks(num_cycles);
}
void
Resource::scheduleExecution(int slot_num)
{
if (latency >= 1) {
scheduleEvent(slot_num, latency);
} else {
execute(slot_num);
}
}
void
Resource::scheduleEvent(int slot_idx, int delay)
{
DPRINTF(Resource, "[tid:%i]: Scheduling event for [sn:%i] on tick %i.\n",
reqs[slot_idx]->inst->readTid(),
reqs[slot_idx]->inst->seqNum,
cpu->ticks(delay) + curTick());
resourceEvent[slot_idx].scheduleEvent(delay);
}
bool
Resource::scheduleEvent(DynInstPtr inst, int delay)
{
int slot_idx = findSlot(inst);
if(slot_idx != -1)
resourceEvent[slot_idx].scheduleEvent(delay);
return slot_idx;
}
void
Resource::unscheduleEvent(int slot_idx)
{
resourceEvent[slot_idx].unscheduleEvent();
}
bool
Resource::unscheduleEvent(DynInstPtr inst)
{
int slot_idx = findSlot(inst);
if(slot_idx != -1)
resourceEvent[slot_idx].unscheduleEvent();
return slot_idx;
}
int ResourceRequest::resReqID = 0;
int ResourceRequest::maxReqCount = 0;
ResourceRequest::ResourceRequest(Resource *_res)
: res(_res), inst(NULL), stagePasses(0), valid(false), doneInResource(false),
completed(false), squashed(false), processing(false),
memStall(false)
{
}
ResourceRequest::~ResourceRequest()
{
#ifdef DEBUG
res->cpu->resReqCount--;
DPRINTF(ResReqCount, "Res. Req %i deleted. resReqCount=%i.\n", reqID,
res->cpu->resReqCount);
#endif
inst = NULL;
}
std::string
ResourceRequest::name()
{
return csprintf("%s[slot:%i]:", res->name(), slotNum);
}
void
ResourceRequest::setRequest(DynInstPtr _inst, int stage_num,
int res_idx, int slot_num, unsigned _cmd)
{
valid = true;
inst = _inst;
stageNum = stage_num;
resIdx = res_idx;
slotNum = slot_num;
cmd = _cmd;
}
void
ResourceRequest::clearRequest()
{
valid = false;
inst = NULL;
stagePasses = 0;
completed = false;
doneInResource = false;
squashed = false;
memStall = false;
}
void
ResourceRequest::freeSlot()
{
assert(res);
// Free Slot So Another Instruction Can Use This Resource
res->freeSlot(slotNum);
}
void
ResourceRequest::done(bool completed)
{
DPRINTF(Resource, "done with request from "
"[sn:%i] [tid:%i].\n",
inst->seqNum, inst->readTid());
setCompleted(completed);
doneInResource = true;
}
ResourceEvent::ResourceEvent()
: Event((Event::Priority)Resource_Event_Pri)
{ }
ResourceEvent::ResourceEvent(Resource *res, int slot_idx)
: Event((Event::Priority)Resource_Event_Pri), resource(res),
slotIdx(slot_idx)
{ }
void
ResourceEvent::init(Resource *res, int slot_idx)
{
resource = res;
slotIdx = slot_idx;
}
void
ResourceEvent::process()
{
resource->execute(slotIdx);
}
const char *
ResourceEvent::description()
{
string desc = resource->name() + "-event:slot[" + to_string(slotIdx)
+ "]";
return desc.c_str();
}
void
ResourceEvent::scheduleEvent(int delay)
{
assert(!scheduled() || squashed());
resource->cpu->reschedule(this,
curTick() + resource->ticks(delay), true);
}