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gpu-compute: Adding context serialization methods to Wavefront

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This patch adds methods to serialize the context of a particular wavefront
to the simulated system memory. Context serialization is used when a wavefront
is preempeted (i.e. context switch).
This commit is contained in:
Alexandru Dutu 2016-09-16 12:32:36 -04:00
parent e9b14d5111
commit bd65ec0744
2 changed files with 137 additions and 0 deletions
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125
src/gpu-compute/wavefront.cc
View file

@ -941,3 +941,128 @@ Wavefront::getStaticContextSize() const
sizeof(privBase) + sizeof(spillBase) + sizeof(ldsChunk) +
computeUnit->wfSize() * sizeof(ReconvergenceStackEntry);
}
void
Wavefront::getContext(const void *out)
{
uint8_t *iter = (uint8_t *)out;
for (int i = 0; i < barCnt.size(); i++) {
*(int *)iter = barCnt[i]; iter += sizeof(barCnt[i]);
}
*(int *)iter = wfId; iter += sizeof(wfId);
*(int *)iter = maxBarCnt; iter += sizeof(maxBarCnt);
*(int *)iter = oldBarrierCnt; iter += sizeof(oldBarrierCnt);
*(int *)iter = barrierCnt; iter += sizeof(barrierCnt);
*(int *)iter = computeUnit->cu_id; iter += sizeof(computeUnit->cu_id);
*(uint32_t *)iter = wgId; iter += sizeof(wgId);
*(uint32_t *)iter = barrierId; iter += sizeof(barrierId);
*(uint64_t *)iter = initMask.to_ullong(); iter += sizeof(initMask.to_ullong());
*(Addr *)iter = privBase; iter += sizeof(privBase);
*(Addr *)iter = spillBase; iter += sizeof(spillBase);
int stackSize = reconvergenceStack.size();
ReconvergenceStackEntry empty = {std::numeric_limits<uint32_t>::max(),
std::numeric_limits<uint32_t>::max(),
std::numeric_limits<uint64_t>::max()};
for (int i = 0; i < workItemId[0].size(); i++) {
if (i < stackSize) {
*(ReconvergenceStackEntry *)iter = *reconvergenceStack.back();
iter += sizeof(ReconvergenceStackEntry);
reconvergenceStack.pop_back();
} else {
*(ReconvergenceStackEntry *)iter = empty;
iter += sizeof(ReconvergenceStackEntry);
}
}
int wf_size = computeUnit->wfSize();
for (int i = 0; i < maxSpVgprs; i++) {
uint32_t vgprIdx = remap(i, sizeof(uint32_t), 1);
for (int lane = 0; lane < wf_size; lane++) {
uint32_t regVal = computeUnit->vrf[simdId]->
read<uint32_t>(vgprIdx,lane);
*(uint32_t *)iter = regVal; iter += sizeof(regVal);
}
}
for (int i = 0; i < maxDpVgprs; i++) {
uint32_t vgprIdx = remap(i, sizeof(uint64_t), 1);
for (int lane = 0; lane < wf_size; lane++) {
uint64_t regVal = computeUnit->vrf[simdId]->
read<uint64_t>(vgprIdx,lane);
*(uint64_t *)iter = regVal; iter += sizeof(regVal);
}
}
for (int i = 0; i < condRegState->numRegs(); i++) {
for (int lane = 0; lane < wf_size; lane++) {
uint64_t regVal = condRegState->read<uint64_t>(i, lane);
*(uint64_t *)iter = regVal; iter += sizeof(regVal);
}
}
/* saving LDS content */
if (ldsChunk)
for (int i = 0; i < ldsChunk->size(); i++) {
char val = ldsChunk->read<char>(i);
*(char *) iter = val; iter += sizeof(val);
}
}
void
Wavefront::setContext(const void *in)
{
uint8_t *iter = (uint8_t *)in;
for (int i = 0; i < barCnt.size(); i++) {
barCnt[i] = *(int *)iter; iter += sizeof(barCnt[i]);
}
wfId = *(int *)iter; iter += sizeof(wfId);
maxBarCnt = *(int *)iter; iter += sizeof(maxBarCnt);
oldBarrierCnt = *(int *)iter; iter += sizeof(oldBarrierCnt);
barrierCnt = *(int *)iter; iter += sizeof(barrierCnt);
computeUnit->cu_id = *(int *)iter; iter += sizeof(computeUnit->cu_id);
wgId = *(uint32_t *)iter; iter += sizeof(wgId);
barrierId = *(uint32_t *)iter; iter += sizeof(barrierId);
initMask = VectorMask(*(uint64_t *)iter); iter += sizeof(initMask);
privBase = *(Addr *)iter; iter += sizeof(privBase);
spillBase = *(Addr *)iter; iter += sizeof(spillBase);
for (int i = 0; i < workItemId[0].size(); i++) {
ReconvergenceStackEntry newEntry = *(ReconvergenceStackEntry *)iter;
iter += sizeof(ReconvergenceStackEntry);
if (newEntry.pc != std::numeric_limits<uint32_t>::max()) {
pushToReconvergenceStack(newEntry.pc, newEntry.rpc,
newEntry.execMask);
}
}
int wf_size = computeUnit->wfSize();
for (int i = 0; i < maxSpVgprs; i++) {
uint32_t vgprIdx = remap(i, sizeof(uint32_t), 1);
for (int lane = 0; lane < wf_size; lane++) {
uint32_t regVal = *(uint32_t *)iter; iter += sizeof(regVal);
computeUnit->vrf[simdId]->write<uint32_t>(vgprIdx, regVal, lane);
}
}
for (int i = 0; i < maxDpVgprs; i++) {
uint32_t vgprIdx = remap(i, sizeof(uint64_t), 1);
for (int lane = 0; lane < wf_size; lane++) {
uint64_t regVal = *(uint64_t *)iter; iter += sizeof(regVal);
computeUnit->vrf[simdId]->write<uint64_t>(vgprIdx, regVal, lane);
}
}
for (int i = 0; i < condRegState->numRegs(); i++) {
for (int lane = 0; lane < wf_size; lane++) {
uint64_t regVal = *(uint64_t *)iter; iter += sizeof(regVal);
condRegState->write<uint64_t>(i, lane, regVal);
}
}
/** Restoring LDS contents */
if (ldsChunk)
for (int i = 0; i < ldsChunk->size(); i++) {
char val = *(char *) iter; iter += sizeof(val);
ldsChunk->write<char>(i, val);
}
}

12
src/gpu-compute/wavefront.hh
View file

@ -354,6 +354,18 @@ class Wavefront : public SimObject
*/
uint32_t getStaticContextSize() const;
/**
* Returns the hardware context as a stream of bytes
* This method is designed for HSAIL execution
*/
void getContext(const void *out);
/**
* Sets the hardware context fromt a stream of bytes
* This method is designed for HSAIL execution
*/
void setContext(const void *in);
private:
/**
* Stack containing Control Flow Graph nodes (i.e., kernel instructions)