gem5/src/gpu-compute/local_memory_pipeline.cc
Tony Gutierrez 00a6346c91 hsail, gpu-compute: remove doGm/SmReturn add completeAcc
we are removing doGmReturn from the GM pipe, and adding completeAcc()
implementations for the HSAIL mem ops. the behavior in doGmReturn is
dependent on HSAIL and HSAIL mem ops, however the completion phase
of memory ops in machine ISA can be very different, even amongst individual
machine ISA mem ops. so we remove this functionality from the pipeline and
allow it to be implemented by the individual instructions.
2016-10-26 22:47:19 -04:00

128 lines
4.3 KiB
C++

/*
* Copyright (c) 2014-2015 Advanced Micro Devices, Inc.
* All rights reserved.
*
* For use for simulation and test purposes only
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. 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.
*
* 3. Neither the name of the copyright holder 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 HOLDER 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.
*
* Author: Sooraj Puthoor
*/
#include "gpu-compute/local_memory_pipeline.hh"
#include "debug/GPUPort.hh"
#include "gpu-compute/compute_unit.hh"
#include "gpu-compute/gpu_dyn_inst.hh"
#include "gpu-compute/shader.hh"
#include "gpu-compute/vector_register_file.hh"
#include "gpu-compute/wavefront.hh"
LocalMemPipeline::LocalMemPipeline(const ComputeUnitParams* p) :
computeUnit(nullptr), lmQueueSize(p->local_mem_queue_size)
{
}
void
LocalMemPipeline::init(ComputeUnit *cu)
{
computeUnit = cu;
_name = computeUnit->name() + ".LocalMemPipeline";
}
void
LocalMemPipeline::exec()
{
// apply any returned shared (LDS) memory operations
GPUDynInstPtr m = !lmReturnedRequests.empty() ?
lmReturnedRequests.front() : nullptr;
bool accessVrf = true;
Wavefront *w = nullptr;
if ((m) && (m->isLoad() || m->isAtomicRet())) {
w = m->wavefront();
accessVrf =
w->computeUnit->vrf[w->simdId]->
vrfOperandAccessReady(m->seqNum(), w, m,
VrfAccessType::WRITE);
}
if (!lmReturnedRequests.empty() && m->latency.rdy() && accessVrf &&
computeUnit->locMemToVrfBus.rdy() && (computeUnit->shader->coissue_return
|| computeUnit->wfWait.at(m->pipeId).rdy())) {
lmReturnedRequests.pop();
w = m->wavefront();
m->completeAcc(m);
// Decrement outstanding request count
computeUnit->shader->ScheduleAdd(&w->outstandingReqs, m->time, -1);
if (m->isStore() || m->isAtomic()) {
computeUnit->shader->ScheduleAdd(&w->outstandingReqsWrLm,
m->time, -1);
}
if (m->isLoad() || m->isAtomic()) {
computeUnit->shader->ScheduleAdd(&w->outstandingReqsRdLm,
m->time, -1);
}
// Mark write bus busy for appropriate amount of time
computeUnit->locMemToVrfBus.set(m->time);
if (computeUnit->shader->coissue_return == 0)
w->computeUnit->wfWait.at(m->pipeId).set(m->time);
}
// If pipeline has executed a local memory instruction
// execute local memory packet and issue the packets
// to LDS
if (!lmIssuedRequests.empty() && lmReturnedRequests.size() < lmQueueSize) {
GPUDynInstPtr m = lmIssuedRequests.front();
bool returnVal = computeUnit->sendToLds(m);
if (!returnVal) {
DPRINTF(GPUPort, "packet was nack'd and put in retry queue");
}
lmIssuedRequests.pop();
}
}
void
LocalMemPipeline::regStats()
{
loadVrfBankConflictCycles
.name(name() + ".load_vrf_bank_conflict_cycles")
.desc("total number of cycles LDS data are delayed before updating "
"the VRF")
;
}