//===- xray-converter.cpp: XRay Trace Conversion --------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Implements the trace conversion functions.
//
//===----------------------------------------------------------------------===//
#include "xray-converter.h"
#include "trie-node.h"
#include "xray-registry.h"
#include "llvm/DebugInfo/Symbolize/Symbolize.h"
#include "llvm/Support/EndianStream.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/FormatVariadic.h"
#include "llvm/Support/ScopedPrinter.h"
#include "llvm/Support/YAMLTraits.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/XRay/InstrumentationMap.h"
#include "llvm/XRay/Trace.h"
#include "llvm/XRay/YAMLXRayRecord.h"
using namespace llvm;
using namespace xray;
// llvm-xray convert
// ----------------------------------------------------------------------------
static cl::SubCommand Convert("convert", "Trace Format Conversion");
static cl::opt<std::string> ConvertInput(cl::Positional,
cl::desc("<xray log file>"),
cl::Required, cl::sub(Convert));
enum class ConvertFormats { BINARY, YAML, CHROME_TRACE_EVENT };
static cl::opt<ConvertFormats> ConvertOutputFormat(
"output-format", cl::desc("output format"),
cl::values(clEnumValN(ConvertFormats::BINARY, "raw", "output in binary"),
clEnumValN(ConvertFormats::YAML, "yaml", "output in yaml"),
clEnumValN(ConvertFormats::CHROME_TRACE_EVENT, "trace_event",
"Output in chrome's trace event format. "
"May be visualized with the Catapult trace viewer.")),
cl::sub(Convert));
static cl::alias ConvertOutputFormat2("f", cl::aliasopt(ConvertOutputFormat),
cl::desc("Alias for -output-format"),
cl::sub(Convert));
static cl::opt<std::string>
ConvertOutput("output", cl::value_desc("output file"), cl::init("-"),
cl::desc("output file; use '-' for stdout"),
cl::sub(Convert));
static cl::alias ConvertOutput2("o", cl::aliasopt(ConvertOutput),
cl::desc("Alias for -output"),
cl::sub(Convert));
static cl::opt<bool>
ConvertSymbolize("symbolize",
cl::desc("symbolize function ids from the input log"),
cl::init(false), cl::sub(Convert));
static cl::alias ConvertSymbolize2("y", cl::aliasopt(ConvertSymbolize),
cl::desc("Alias for -symbolize"),
cl::sub(Convert));
static cl::opt<std::string>
ConvertInstrMap("instr_map",
cl::desc("binary with the instrumentation map, or "
"a separate instrumentation map"),
cl::value_desc("binary with xray_instr_map"),
cl::sub(Convert), cl::init(""));
static cl::alias ConvertInstrMap2("m", cl::aliasopt(ConvertInstrMap),
cl::desc("Alias for -instr_map"),
cl::sub(Convert));
static cl::opt<bool> ConvertSortInput(
"sort",
cl::desc("determines whether to sort input log records by timestamp"),
cl::sub(Convert), cl::init(true));
static cl::alias ConvertSortInput2("s", cl::aliasopt(ConvertSortInput),
cl::desc("Alias for -sort"),
cl::sub(Convert));
using llvm::yaml::Output;
void TraceConverter::exportAsYAML(const Trace &Records, raw_ostream &OS) {
YAMLXRayTrace Trace;
const auto &FH = Records.getFileHeader();
Trace.Header = {FH.Version, FH.Type, FH.ConstantTSC, FH.NonstopTSC,
FH.CycleFrequency};
Trace.Records.reserve(Records.size());
for (const auto &R : Records) {
Trace.Records.push_back({R.RecordType, R.CPU, R.Type, R.FuncId,
Symbolize ? FuncIdHelper.SymbolOrNumber(R.FuncId)
: llvm::to_string(R.FuncId),
R.TSC, R.TId, R.PId, R.CallArgs});
}
Output Out(OS, nullptr, 0);
Out << Trace;
}
void TraceConverter::exportAsRAWv1(const Trace &Records, raw_ostream &OS) {
// First write out the file header, in the correct endian-appropriate format
// (XRay assumes currently little endian).
support::endian::Writer Writer(OS, support::endianness::little);
const auto &FH = Records.getFileHeader();
Writer.write(FH.Version);
Writer.write(FH.Type);
uint32_t Bitfield{0};
if (FH.ConstantTSC)
Bitfield |= 1uL;
if (FH.NonstopTSC)
Bitfield |= 1uL << 1;
Writer.write(Bitfield);
Writer.write(FH.CycleFrequency);
// There's 16 bytes of padding at the end of the file header.
static constexpr uint32_t Padding4B = 0;
Writer.write(Padding4B);
Writer.write(Padding4B);
Writer.write(Padding4B);
Writer.write(Padding4B);
// Then write out the rest of the records, still in an endian-appropriate
// format.
for (const auto &R : Records) {
Writer.write(R.RecordType);
// The on disk naive raw format uses 8 bit CPUs, but the record has 16.
// There's no choice but truncation.
Writer.write(static_cast<uint8_t>(R.CPU));
switch (R.Type) {
case RecordTypes::ENTER:
case RecordTypes::ENTER_ARG:
Writer.write(uint8_t{0});
break;
case RecordTypes::EXIT:
Writer.write(uint8_t{1});
break;
case RecordTypes::TAIL_EXIT:
Writer.write(uint8_t{2});
break;
}
Writer.write(R.FuncId);
Writer.write(R.TSC);
Writer.write(R.TId);
if (FH.Version >= 3)
Writer.write(R.PId);
else
Writer.write(Padding4B);
Writer.write(Padding4B);
Writer.write(Padding4B);
}
}
namespace {
// A structure that allows building a dictionary of stack ids for the Chrome
// trace event format.
struct StackIdData {
// Each Stack of function calls has a unique ID.
unsigned id;
// Bookkeeping so that IDs can be maintained uniquely across threads.
// Traversal keeps sibling pointers to other threads stacks. This is helpful
// to determine when a thread encounters a new stack and should assign a new
// unique ID.
SmallVector<TrieNode<StackIdData> *, 4> siblings;
};
using StackTrieNode = TrieNode<StackIdData>;
// A helper function to find the sibling nodes for an encountered function in a
// thread of execution. Relies on the invariant that each time a new node is
// traversed in a thread, sibling bidirectional pointers are maintained.
SmallVector<StackTrieNode *, 4>
findSiblings(StackTrieNode *parent, int32_t FnId, uint32_t TId,
const DenseMap<uint32_t, SmallVector<StackTrieNode *, 4>>
&StackRootsByThreadId) {
SmallVector<StackTrieNode *, 4> Siblings{};
if (parent == nullptr) {
for (auto map_iter : StackRootsByThreadId) {
// Only look for siblings in other threads.
if (map_iter.first != TId)
for (auto node_iter : map_iter.second) {
if (node_iter->FuncId == FnId)
Siblings.push_back(node_iter);
}
}
return Siblings;
}
for (auto *ParentSibling : parent->ExtraData.siblings)
for (auto node_iter : ParentSibling->Callees)
if (node_iter->FuncId == FnId)
Siblings.push_back(node_iter);
return Siblings;
}
// Given a function being invoked in a thread with id TId, finds and returns the
// StackTrie representing the function call stack. If no node exists, creates
// the node. Assigns unique IDs to stacks newly encountered among all threads
// and keeps sibling links up to when creating new nodes.
StackTrieNode *findOrCreateStackNode(
StackTrieNode *Parent, int32_t FuncId, uint32_t TId,
DenseMap<uint32_t, SmallVector<StackTrieNode *, 4>> &StackRootsByThreadId,
DenseMap<unsigned, StackTrieNode *> &StacksByStackId, unsigned *id_counter,
std::forward_list<StackTrieNode> &NodeStore) {
SmallVector<StackTrieNode *, 4> &ParentCallees =
Parent == nullptr ? StackRootsByThreadId[TId] : Parent->Callees;
auto match = find_if(ParentCallees, [FuncId](StackTrieNode *ParentCallee) {
return FuncId == ParentCallee->FuncId;
});
if (match != ParentCallees.end())
return *match;
SmallVector<StackTrieNode *, 4> siblings =
findSiblings(Parent, FuncId, TId, StackRootsByThreadId);
if (siblings.empty()) {
NodeStore.push_front({FuncId, Parent, {}, {(*id_counter)++, {}}});
StackTrieNode *CurrentStack = &NodeStore.front();
StacksByStackId[*id_counter - 1] = CurrentStack;
ParentCallees.push_back(CurrentStack);
return CurrentStack;
}
unsigned stack_id = siblings[0]->ExtraData.id;
NodeStore.push_front({FuncId, Parent, {}, {stack_id, std::move(siblings)}});
StackTrieNode *CurrentStack = &NodeStore.front();
for (auto *sibling : CurrentStack->ExtraData.siblings)
sibling->ExtraData.siblings.push_back(CurrentStack);
ParentCallees.push_back(CurrentStack);
return CurrentStack;
}
void writeTraceViewerRecord(uint16_t Version, raw_ostream &OS, int32_t FuncId,
uint32_t TId, uint32_t PId, bool Symbolize,
const FuncIdConversionHelper &FuncIdHelper,
double EventTimestampUs,
const StackTrieNode &StackCursor,
StringRef FunctionPhenotype) {
OS << " ";
if (Version >= 3) {
OS << llvm::formatv(
R"({ "name" : "{0}", "ph" : "{1}", "tid" : "{2}", "pid" : "{3}", )"
R"("ts" : "{4:f4}", "sf" : "{5}" })",
(Symbolize ? FuncIdHelper.SymbolOrNumber(FuncId)
: llvm::to_string(FuncId)),
FunctionPhenotype, TId, PId, EventTimestampUs,
StackCursor.ExtraData.id);
} else {
OS << llvm::formatv(
R"({ "name" : "{0}", "ph" : "{1}", "tid" : "{2}", "pid" : "1", )"
R"("ts" : "{3:f3}", "sf" : "{4}" })",
(Symbolize ? FuncIdHelper.SymbolOrNumber(FuncId)
: llvm::to_string(FuncId)),
FunctionPhenotype, TId, EventTimestampUs, StackCursor.ExtraData.id);
}
}
} // namespace
void TraceConverter::exportAsChromeTraceEventFormat(const Trace &Records,
raw_ostream &OS) {
const auto &FH = Records.getFileHeader();
auto Version = FH.Version;
auto CycleFreq = FH.CycleFrequency;
unsigned id_counter = 0;
OS << "{\n \"traceEvents\": [";
DenseMap<uint32_t, StackTrieNode *> StackCursorByThreadId{};
DenseMap<uint32_t, SmallVector<StackTrieNode *, 4>> StackRootsByThreadId{};
DenseMap<unsigned, StackTrieNode *> StacksByStackId{};
std::forward_list<StackTrieNode> NodeStore{};
int loop_count = 0;
for (const auto &R : Records) {
if (loop_count++ == 0)
OS << "\n";
else
OS << ",\n";
// Chrome trace event format always wants data in micros.
// CyclesPerMicro = CycleHertz / 10^6
// TSC / CyclesPerMicro == TSC * 10^6 / CycleHertz == MicroTimestamp
// Could lose some precision here by converting the TSC to a double to
// multiply by the period in micros. 52 bit mantissa is a good start though.
// TODO: Make feature request to Chrome Trace viewer to accept ticks and a
// frequency or do some more involved calculation to avoid dangers of
// conversion.
double EventTimestampUs = double(1000000) / CycleFreq * double(R.TSC);
StackTrieNode *&StackCursor = StackCursorByThreadId[R.TId];
switch (R.Type) {
case RecordTypes::ENTER:
case RecordTypes::ENTER_ARG:
StackCursor = findOrCreateStackNode(StackCursor, R.FuncId, R.TId,
StackRootsByThreadId, StacksByStackId,
&id_counter, NodeStore);
// Each record is represented as a json dictionary with function name,
// type of B for begin or E for end, thread id, process id,
// timestamp in microseconds, and a stack frame id. The ids are logged
// in an id dictionary after the events.
writeTraceViewerRecord(Version, OS, R.FuncId, R.TId, R.PId, Symbolize,
FuncIdHelper, EventTimestampUs, *StackCursor, "B");
break;
case RecordTypes::EXIT:
case RecordTypes::TAIL_EXIT:
// No entries to record end for.
if (StackCursor == nullptr)
break;
// Should we emit an END record anyway or account this condition?
// (And/Or in loop termination below)
StackTrieNode *PreviousCursor = nullptr;
do {
if (PreviousCursor != nullptr) {
OS << ",\n";
}
writeTraceViewerRecord(Version, OS, StackCursor->FuncId, R.TId, R.PId,
Symbolize, FuncIdHelper, EventTimestampUs,
*StackCursor, "E");
PreviousCursor = StackCursor;
StackCursor = StackCursor->Parent;
} while (PreviousCursor->FuncId != R.FuncId && StackCursor != nullptr);
break;
}
}
OS << "\n ],\n"; // Close the Trace Events array.
OS << " "
<< "\"displayTimeUnit\": \"ns\",\n";
// The stackFrames dictionary substantially reduces size of the output file by
// avoiding repeating the entire call stack of function names for each entry.
OS << R"( "stackFrames": {)";
int stack_frame_count = 0;
for (auto map_iter : StacksByStackId) {
if (stack_frame_count++ == 0)
OS << "\n";
else
OS << ",\n";
OS << " ";
OS << llvm::formatv(
R"("{0}" : { "name" : "{1}")", map_iter.first,
(Symbolize ? FuncIdHelper.SymbolOrNumber(map_iter.second->FuncId)
: llvm::to_string(map_iter.second->FuncId)));
if (map_iter.second->Parent != nullptr)
OS << llvm::formatv(R"(, "parent": "{0}")",
map_iter.second->Parent->ExtraData.id);
OS << " }";
}
OS << "\n }\n"; // Close the stack frames map.
OS << "}\n"; // Close the JSON entry.
}
namespace llvm {
namespace xray {
static CommandRegistration Unused(&Convert, []() -> Error {
// FIXME: Support conversion to BINARY when upgrading XRay trace versions.
InstrumentationMap Map;
if (!ConvertInstrMap.empty()) {
auto InstrumentationMapOrError = loadInstrumentationMap(ConvertInstrMap);
if (!InstrumentationMapOrError)
return joinErrors(make_error<StringError>(
Twine("Cannot open instrumentation map '") +
ConvertInstrMap + "'",
std::make_error_code(std::errc::invalid_argument)),
InstrumentationMapOrError.takeError());
Map = std::move(*InstrumentationMapOrError);
}
const auto &FunctionAddresses = Map.getFunctionAddresses();
symbolize::LLVMSymbolizer::Options Opts(
symbolize::FunctionNameKind::LinkageName, true, true, false, "");
symbolize::LLVMSymbolizer Symbolizer(Opts);
llvm::xray::FuncIdConversionHelper FuncIdHelper(ConvertInstrMap, Symbolizer,
FunctionAddresses);
llvm::xray::TraceConverter TC(FuncIdHelper, ConvertSymbolize);
std::error_code EC;
raw_fd_ostream OS(ConvertOutput, EC,
ConvertOutputFormat == ConvertFormats::BINARY
? sys::fs::OpenFlags::F_None
: sys::fs::OpenFlags::F_Text);
if (EC)
return make_error<StringError>(
Twine("Cannot open file '") + ConvertOutput + "' for writing.", EC);
auto TraceOrErr = loadTraceFile(ConvertInput, ConvertSortInput);
if (!TraceOrErr)
return joinErrors(
make_error<StringError>(
Twine("Failed loading input file '") + ConvertInput + "'.",
std::make_error_code(std::errc::executable_format_error)),
TraceOrErr.takeError());
auto &T = *TraceOrErr;
switch (ConvertOutputFormat) {
case ConvertFormats::YAML:
TC.exportAsYAML(T, OS);
break;
case ConvertFormats::BINARY:
TC.exportAsRAWv1(T, OS);
break;
case ConvertFormats::CHROME_TRACE_EVENT:
TC.exportAsChromeTraceEventFormat(T, OS);
break;
}
return Error::success();
});
} // namespace xray
} // namespace llvm