Skip to content

Commit

Permalink
[memprof] Introduce writeMemProf (NFC) (#87698)
Browse files Browse the repository at this point in the history 
This patch refactors the serialization of MemProf data to a switch
statement style:

  switch (Version) {
  case Version0:
    return ...;
  case Version1:
    return ...;
  }

just like IndexedMemProfRecord::serialize.

A reasonable amount of code is shared and factored out to helper
functions between writeMemProfV0 and writeMemProfV1 to the extent that
doens't hamper readability.
  • Loading branch information
@kazutakahirata
kazutakahirata committed Apr 4, 2024
1 parent 74373c1 commit fd2a5c4
Showing 1 changed file with 142 additions and 76 deletions.
218 changes: 142 additions & 76 deletions llvm/lib/ProfileData/InstrProfWriter.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -414,6 +414,144 @@ static void setSummary(IndexedInstrProf::Summary *TheSummary,
TheSummary->setEntry(I, Res[I]);
}

// Serialize Schema.
static void writeMemProfSchema(ProfOStream &OS,
const memprof::MemProfSchema &Schema) {
OS.write(static_cast<uint64_t>(Schema.size()));
for (const auto Id : Schema)
OS.write(static_cast<uint64_t>(Id));
}

// Serialize MemProfRecordData. Return RecordTableOffset.
static uint64_t writeMemProfRecords(
ProfOStream &OS,
llvm::MapVector<GlobalValue::GUID, memprof::IndexedMemProfRecord>
&MemProfRecordData,
memprof::MemProfSchema *Schema) {
auto RecordWriter =
std::make_unique<memprof::RecordWriterTrait>(memprof::Version1);
RecordWriter->Schema = Schema;
OnDiskChainedHashTableGenerator<memprof::RecordWriterTrait>
RecordTableGenerator;
for (auto &I : MemProfRecordData) {
// Insert the key (func hash) and value (memprof record).
RecordTableGenerator.insert(I.first, I.second, *RecordWriter.get());
}
// Release the memory of this MapVector as it is no longer needed.
MemProfRecordData.clear();

// The call to Emit invokes RecordWriterTrait::EmitData which destructs
// the memprof record copies owned by the RecordTableGenerator. This works
// because the RecordTableGenerator is not used after this point.
return RecordTableGenerator.Emit(OS.OS, *RecordWriter);
}

// Serialize MemProfFrameData. Return FrameTableOffset.
static uint64_t writeMemProfFrames(
ProfOStream &OS,
llvm::MapVector<memprof::FrameId, memprof::Frame> &MemProfFrameData) {
auto FrameWriter = std::make_unique<memprof::FrameWriterTrait>();
OnDiskChainedHashTableGenerator<memprof::FrameWriterTrait>
FrameTableGenerator;
for (auto &I : MemProfFrameData) {
// Insert the key (frame id) and value (frame contents).
FrameTableGenerator.insert(I.first, I.second);
}
// Release the memory of this MapVector as it is no longer needed.
MemProfFrameData.clear();

return FrameTableGenerator.Emit(OS.OS, *FrameWriter);
}

static Error writeMemProfV0(
ProfOStream &OS,
llvm::MapVector<GlobalValue::GUID, memprof::IndexedMemProfRecord>
&MemProfRecordData,
llvm::MapVector<memprof::FrameId, memprof::Frame> &MemProfFrameData) {
uint64_t HeaderUpdatePos = OS.tell();
OS.write(0ULL); // Reserve space for the memprof record table offset.
OS.write(0ULL); // Reserve space for the memprof frame payload offset.
OS.write(0ULL); // Reserve space for the memprof frame table offset.

auto Schema = memprof::PortableMemInfoBlock::getSchema();
writeMemProfSchema(OS, Schema);

uint64_t RecordTableOffset =
writeMemProfRecords(OS, MemProfRecordData, &Schema);

uint64_t FramePayloadOffset = OS.tell();
uint64_t FrameTableOffset = writeMemProfFrames(OS, MemProfFrameData);

uint64_t Header[] = {RecordTableOffset, FramePayloadOffset, FrameTableOffset};
OS.patch({{HeaderUpdatePos, Header, std::size(Header)}});

return Error::success();
}

static Error writeMemProfV1(
ProfOStream &OS,
llvm::MapVector<GlobalValue::GUID, memprof::IndexedMemProfRecord>
&MemProfRecordData,
llvm::MapVector<memprof::FrameId, memprof::Frame> &MemProfFrameData) {
OS.write(memprof::Version0);
uint64_t HeaderUpdatePos = OS.tell();
OS.write(0ULL); // Reserve space for the memprof record table offset.
OS.write(0ULL); // Reserve space for the memprof frame payload offset.
OS.write(0ULL); // Reserve space for the memprof frame table offset.

auto Schema = memprof::PortableMemInfoBlock::getSchema();
writeMemProfSchema(OS, Schema);

uint64_t RecordTableOffset =
writeMemProfRecords(OS, MemProfRecordData, &Schema);

uint64_t FramePayloadOffset = OS.tell();
uint64_t FrameTableOffset = writeMemProfFrames(OS, MemProfFrameData);

uint64_t Header[] = {RecordTableOffset, FramePayloadOffset, FrameTableOffset};
OS.patch({{HeaderUpdatePos, Header, std::size(Header)}});

return Error::success();
}

// The MemProf profile data includes a simple schema
// with the format described below followed by the hashtable:
// uint64_t Version
// uint64_t RecordTableOffset = RecordTableGenerator.Emit
// uint64_t FramePayloadOffset = Stream offset before emitting the frame table
// uint64_t FrameTableOffset = FrameTableGenerator.Emit
// uint64_t Num schema entries
// uint64_t Schema entry 0
// uint64_t Schema entry 1
// ....
// uint64_t Schema entry N - 1
// OnDiskChainedHashTable MemProfRecordData
// OnDiskChainedHashTable MemProfFrameData
static Error writeMemProf(
ProfOStream &OS,
llvm::MapVector<GlobalValue::GUID, memprof::IndexedMemProfRecord>
&MemProfRecordData,
llvm::MapVector<memprof::FrameId, memprof::Frame> &MemProfFrameData,
memprof::IndexedVersion MemProfVersionRequested) {

switch (MemProfVersionRequested) {
case memprof::Version0:
return writeMemProfV0(OS, MemProfRecordData, MemProfFrameData);
case memprof::Version1:
return writeMemProfV1(OS, MemProfRecordData, MemProfFrameData);
case memprof::Version2:
// TODO: Implement. Fall through to the error handling below for now.
break;
}

return make_error<InstrProfError>(
instrprof_error::unsupported_version,
formatv("MemProf version {} not supported; "
"requires version between {} and {}, inclusive",
MemProfVersionRequested, memprof::MinimumSupportedVersion,
memprof::MaximumSupportedVersion));
}

Error InstrProfWriter::writeImpl(ProfOStream &OS) {
using namespace IndexedInstrProf;
using namespace support;
Expand Down Expand Up @@ -517,85 +655,13 @@ Error InstrProfWriter::writeImpl(ProfOStream &OS) {
// Write the hash table.
uint64_t HashTableStart = Generator.Emit(OS.OS, *InfoObj);

// Write the MemProf profile data if we have it. This includes a simple schema
// with the format described below followed by the hashtable:
// uint64_t Version
// uint64_t RecordTableOffset = RecordTableGenerator.Emit
// uint64_t FramePayloadOffset = Stream offset before emitting the frame table
// uint64_t FrameTableOffset = FrameTableGenerator.Emit
// uint64_t Num schema entries
// uint64_t Schema entry 0
// uint64_t Schema entry 1
// ....
// uint64_t Schema entry N - 1
// OnDiskChainedHashTable MemProfRecordData
// OnDiskChainedHashTable MemProfFrameData
// Write the MemProf profile data if we have it.
uint64_t MemProfSectionStart = 0;
if (static_cast<bool>(ProfileKind & InstrProfKind::MemProf)) {
if (MemProfVersionRequested < memprof::MinimumSupportedVersion ||
MemProfVersionRequested > memprof::MaximumSupportedVersion) {
return make_error<InstrProfError>(
instrprof_error::unsupported_version,
formatv("MemProf version {} not supported; "
"requires version between {} and {}, inclusive",
MemProfVersionRequested, memprof::MinimumSupportedVersion,
memprof::MaximumSupportedVersion));
}

MemProfSectionStart = OS.tell();

if (MemProfVersionRequested >= memprof::Version1)
OS.write(MemProfVersionRequested);

OS.write(0ULL); // Reserve space for the memprof record table offset.
OS.write(0ULL); // Reserve space for the memprof frame payload offset.
OS.write(0ULL); // Reserve space for the memprof frame table offset.

auto Schema = memprof::PortableMemInfoBlock::getSchema();
OS.write(static_cast<uint64_t>(Schema.size()));
for (const auto Id : Schema) {
OS.write(static_cast<uint64_t>(Id));
}

auto RecordWriter =
std::make_unique<memprof::RecordWriterTrait>(memprof::Version1);
RecordWriter->Schema = &Schema;
OnDiskChainedHashTableGenerator<memprof::RecordWriterTrait>
RecordTableGenerator;
for (auto &I : MemProfRecordData) {
// Insert the key (func hash) and value (memprof record).
RecordTableGenerator.insert(I.first, I.second, *RecordWriter.get());
}
// Release the memory of this MapVector as it is no longer needed.
MemProfRecordData.clear();

// The call to Emit invokes RecordWriterTrait::EmitData which destructs
// the memprof record copies owned by the RecordTableGenerator. This works
// because the RecordTableGenerator is not used after this point.
uint64_t RecordTableOffset =
RecordTableGenerator.Emit(OS.OS, *RecordWriter);

uint64_t FramePayloadOffset = OS.tell();

auto FrameWriter = std::make_unique<memprof::FrameWriterTrait>();
OnDiskChainedHashTableGenerator<memprof::FrameWriterTrait>
FrameTableGenerator;
for (auto &I : MemProfFrameData) {
// Insert the key (frame id) and value (frame contents).
FrameTableGenerator.insert(I.first, I.second);
}
// Release the memory of this MapVector as it is no longer needed.
MemProfFrameData.clear();

uint64_t FrameTableOffset = FrameTableGenerator.Emit(OS.OS, *FrameWriter);

uint64_t Header[] = {RecordTableOffset, FramePayloadOffset,
FrameTableOffset};
uint64_t HeaderUpdatePos = MemProfSectionStart;
if (MemProfVersionRequested >= memprof::Version1)
// The updates go just after the version field.
HeaderUpdatePos += sizeof(uint64_t);
OS.patch({{HeaderUpdatePos, Header, std::size(Header)}});
if (auto E = writeMemProf(OS, MemProfRecordData, MemProfFrameData,
MemProfVersionRequested))
return E;
}

// BinaryIdSection has two parts:
Expand Down

0 comments on commit fd2a5c4

Please sign in to comment.