tools/llvm-xray/xray-converter.cpp

   1 //===- xray-converter.cpp: XRay Trace Conversion --------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // Implements the trace conversion functions.
  10 //
  11 //===----------------------------------------------------------------------===//
  12 #include "xray-converter.h"
  13
  14 #include "trie-node.h"
  15 #include "xray-registry.h"
  16 #include "llvm/DebugInfo/Symbolize/Symbolize.h"
  17 #include "llvm/Support/EndianStream.h"
  18 #include "llvm/Support/FileSystem.h"
  19 #include "llvm/Support/FormatVariadic.h"
  20 #include "llvm/Support/ScopedPrinter.h"
  21 #include "llvm/Support/YAMLTraits.h"
  22 #include "llvm/Support/raw_ostream.h"
  23 #include "llvm/XRay/InstrumentationMap.h"
  24 #include "llvm/XRay/Trace.h"
  25 #include "llvm/XRay/YAMLXRayRecord.h"
  26
  27 using namespace llvm;
  28 using namespace xray;
  29
  30 // llvm-xray convert
  31 // ----------------------------------------------------------------------------
  32 static cl::SubCommand Convert("convert", "Trace Format Conversion");
  33 static cl::opt<std::string> ConvertInput(cl::Positional,
  34                                          cl::desc("<xray log file>"),
  35                                          cl::Required, cl::sub(Convert));
  36 enum class ConvertFormats { BINARY, YAML, CHROME_TRACE_EVENT };
  37 static cl::opt<ConvertFormats> ConvertOutputFormat(
  38     "output-format", cl::desc("output format"),
  39     cl::values(clEnumValN(ConvertFormats::BINARY, "raw", "output in binary"),
  40                clEnumValN(ConvertFormats::YAML, "yaml", "output in yaml"),
  41                clEnumValN(ConvertFormats::CHROME_TRACE_EVENT, "trace_event",
  42                           "Output in chrome's trace event format. "
  43                           "May be visualized with the Catapult trace viewer.")),
  44     cl::sub(Convert));
  45 static cl::alias ConvertOutputFormat2("f", cl::aliasopt(ConvertOutputFormat),
  46                                       cl::desc("Alias for -output-format"),
  47                                       cl::sub(Convert));
  48 static cl::opt<std::string>
  49     ConvertOutput("output", cl::value_desc("output file"), cl::init("-"),
  50                   cl::desc("output file; use '-' for stdout"),
  51                   cl::sub(Convert));
  52 static cl::alias ConvertOutput2("o", cl::aliasopt(ConvertOutput),
  53                                 cl::desc("Alias for -output"),
  54                                 cl::sub(Convert));
  55
  56 static cl::opt<bool>
  57     ConvertSymbolize("symbolize",
  58                      cl::desc("symbolize function ids from the input log"),
  59                      cl::init(false), cl::sub(Convert));
  60 static cl::alias ConvertSymbolize2("y", cl::aliasopt(ConvertSymbolize),
  61                                    cl::desc("Alias for -symbolize"),
  62                                    cl::sub(Convert));
  63
  64 static cl::opt<std::string>
  65     ConvertInstrMap("instr_map",
  66                     cl::desc("binary with the instrumentation map, or "
  67                              "a separate instrumentation map"),
  68                     cl::value_desc("binary with xray_instr_map"),
  69                     cl::sub(Convert), cl::init(""));
  70 static cl::alias ConvertInstrMap2("m", cl::aliasopt(ConvertInstrMap),
  71                                   cl::desc("Alias for -instr_map"),
  72                                   cl::sub(Convert));
  73 static cl::opt<bool> ConvertSortInput(
  74     "sort",
  75     cl::desc("determines whether to sort input log records by timestamp"),
  76     cl::sub(Convert), cl::init(true));
  77 static cl::alias ConvertSortInput2("s", cl::aliasopt(ConvertSortInput),
  78                                    cl::desc("Alias for -sort"),
  79                                    cl::sub(Convert));
  80
  81 using llvm::yaml::Output;
  82
  83 void TraceConverter::exportAsYAML(const Trace &Records, raw_ostream &OS) {
  84   YAMLXRayTrace Trace;
  85   const auto &FH = Records.getFileHeader();
  86   Trace.Header = {FH.Version, FH.Type, FH.ConstantTSC, FH.NonstopTSC,
  87                   FH.CycleFrequency};
  88   Trace.Records.reserve(Records.size());
  89   for (const auto &R : Records) {
  90     Trace.Records.push_back({R.RecordType, R.CPU, R.Type, R.FuncId,
  91                              Symbolize ? FuncIdHelper.SymbolOrNumber(R.FuncId)
  92                                        : llvm::to_string(R.FuncId),
  93                              R.TSC, R.TId, R.PId, R.CallArgs, R.Data});
  94   }
  95   Output Out(OS, nullptr, 0);
  96   Out.setWriteDefaultValues(false);
  97   Out << Trace;
  98 }
  99
 100 void TraceConverter::exportAsRAWv1(const Trace &Records, raw_ostream &OS) {
 101   // First write out the file header, in the correct endian-appropriate format
 102   // (XRay assumes currently little endian).
 103   support::endian::Writer Writer(OS, support::endianness::little);
 104   const auto &FH = Records.getFileHeader();
 105   Writer.write(FH.Version);
 106   Writer.write(FH.Type);
 107   uint32_t Bitfield{0};
 108   if (FH.ConstantTSC)
 109     Bitfield |= 1uL;
 110   if (FH.NonstopTSC)
 111     Bitfield |= 1uL << 1;
 112   Writer.write(Bitfield);
 113   Writer.write(FH.CycleFrequency);
 114
 115   // There's 16 bytes of padding at the end of the file header.
 116   static constexpr uint32_t Padding4B = 0;
 117   Writer.write(Padding4B);
 118   Writer.write(Padding4B);
 119   Writer.write(Padding4B);
 120   Writer.write(Padding4B);
 121
 122   // Then write out the rest of the records, still in an endian-appropriate
 123   // format.
 124   for (const auto &R : Records) {
 125     switch (R.Type) {
 126     case RecordTypes::ENTER:
 127     case RecordTypes::ENTER_ARG:
 128       Writer.write(R.RecordType);
 129       Writer.write(static_cast<uint8_t>(R.CPU));
 130       Writer.write(uint8_t{0});
 131       break;
 132     case RecordTypes::EXIT:
 133       Writer.write(R.RecordType);
 134       Writer.write(static_cast<uint8_t>(R.CPU));
 135       Writer.write(uint8_t{1});
 136       break;
 137     case RecordTypes::TAIL_EXIT:
 138       Writer.write(R.RecordType);
 139       Writer.write(static_cast<uint8_t>(R.CPU));
 140       Writer.write(uint8_t{2});
 141       break;
 142     case RecordTypes::CUSTOM_EVENT:
 143     case RecordTypes::TYPED_EVENT:
 144       // Skip custom and typed event records for v1 logs.
 145       continue;
 146     }
 147     Writer.write(R.FuncId);
 148     Writer.write(R.TSC);
 149     Writer.write(R.TId);
 150
 151     if (FH.Version >= 3)
 152       Writer.write(R.PId);
 153     else
 154       Writer.write(Padding4B);
 155
 156     Writer.write(Padding4B);
 157     Writer.write(Padding4B);
 158   }
 159 }
 160
 161 namespace {
 162
 163 // A structure that allows building a dictionary of stack ids for the Chrome
 164 // trace event format.
 165 struct StackIdData {
 166   // Each Stack of function calls has a unique ID.
 167   unsigned id;
 168
 169   // Bookkeeping so that IDs can be maintained uniquely across threads.
 170   // Traversal keeps sibling pointers to other threads stacks. This is helpful
 171   // to determine when a thread encounters a new stack and should assign a new
 172   // unique ID.
 173   SmallVector<TrieNode<StackIdData> *, 4> siblings;
 174 };
 175
 176 using StackTrieNode = TrieNode<StackIdData>;
 177
 178 // A helper function to find the sibling nodes for an encountered function in a
 179 // thread of execution. Relies on the invariant that each time a new node is
 180 // traversed in a thread, sibling bidirectional pointers are maintained.
 181 SmallVector<StackTrieNode *, 4>
 182 findSiblings(StackTrieNode *parent, int32_t FnId, uint32_t TId,
 183              const DenseMap<uint32_t, SmallVector<StackTrieNode *, 4>>
 184                  &StackRootsByThreadId) {
 185
 186   SmallVector<StackTrieNode *, 4> Siblings{};
 187
 188   if (parent == nullptr) {
 189     for (auto map_iter : StackRootsByThreadId) {
 190       // Only look for siblings in other threads.
 191       if (map_iter.first != TId)
 192         for (auto node_iter : map_iter.second) {
 193           if (node_iter->FuncId == FnId)
 194             Siblings.push_back(node_iter);
 195         }
 196     }
 197     return Siblings;
 198   }
 199
 200   for (auto *ParentSibling : parent->ExtraData.siblings)
 201     for (auto node_iter : ParentSibling->Callees)
 202       if (node_iter->FuncId == FnId)
 203         Siblings.push_back(node_iter);
 204
 205   return Siblings;
 206 }
 207
 208 // Given a function being invoked in a thread with id TId, finds and returns the
 209 // StackTrie representing the function call stack. If no node exists, creates
 210 // the node. Assigns unique IDs to stacks newly encountered among all threads
 211 // and keeps sibling links up to when creating new nodes.
 212 StackTrieNode *findOrCreateStackNode(
 213     StackTrieNode *Parent, int32_t FuncId, uint32_t TId,
 214     DenseMap<uint32_t, SmallVector<StackTrieNode *, 4>> &StackRootsByThreadId,
 215     DenseMap<unsigned, StackTrieNode *> &StacksByStackId, unsigned *id_counter,
 216     std::forward_list<StackTrieNode> &NodeStore) {
 217   SmallVector<StackTrieNode *, 4> &ParentCallees =
 218       Parent == nullptr ? StackRootsByThreadId[TId] : Parent->Callees;
 219   auto match = find_if(ParentCallees, [FuncId](StackTrieNode *ParentCallee) {
 220     return FuncId == ParentCallee->FuncId;
 221   });
 222   if (match != ParentCallees.end())
 223     return *match;
 224
 225   SmallVector<StackTrieNode *, 4> siblings =
 226       findSiblings(Parent, FuncId, TId, StackRootsByThreadId);
 227   if (siblings.empty()) {
 228     NodeStore.push_front({FuncId, Parent, {}, {(*id_counter)++, {}}});
 229     StackTrieNode *CurrentStack = &NodeStore.front();
 230     StacksByStackId[*id_counter - 1] = CurrentStack;
 231     ParentCallees.push_back(CurrentStack);
 232     return CurrentStack;
 233   }
 234   unsigned stack_id = siblings[0]->ExtraData.id;
 235   NodeStore.push_front({FuncId, Parent, {}, {stack_id, std::move(siblings)}});
 236   StackTrieNode *CurrentStack = &NodeStore.front();
 237   for (auto *sibling : CurrentStack->ExtraData.siblings)
 238     sibling->ExtraData.siblings.push_back(CurrentStack);
 239   ParentCallees.push_back(CurrentStack);
 240   return CurrentStack;
 241 }
 242
 243 void writeTraceViewerRecord(uint16_t Version, raw_ostream &OS, int32_t FuncId,
 244                             uint32_t TId, uint32_t PId, bool Symbolize,
 245                             const FuncIdConversionHelper &FuncIdHelper,
 246                             double EventTimestampUs,
 247                             const StackTrieNode &StackCursor,
 248                             StringRef FunctionPhenotype) {
 249   OS << "    ";
 250   if (Version >= 3) {
 251     OS << llvm::formatv(
 252         R"({ "name" : "{0}", "ph" : "{1}", "tid" : "{2}", "pid" : "{3}", )"
 253         R"("ts" : "{4:f4}", "sf" : "{5}" })",
 254         (Symbolize ? FuncIdHelper.SymbolOrNumber(FuncId)
 255                    : llvm::to_string(FuncId)),
 256         FunctionPhenotype, TId, PId, EventTimestampUs,
 257         StackCursor.ExtraData.id);
 258   } else {
 259     OS << llvm::formatv(
 260         R"({ "name" : "{0}", "ph" : "{1}", "tid" : "{2}", "pid" : "1", )"
 261         R"("ts" : "{3:f3}", "sf" : "{4}" })",
 262         (Symbolize ? FuncIdHelper.SymbolOrNumber(FuncId)
 263                    : llvm::to_string(FuncId)),
 264         FunctionPhenotype, TId, EventTimestampUs, StackCursor.ExtraData.id);
 265   }
 266 }
 267
 268 } // namespace
 269
 270 void TraceConverter::exportAsChromeTraceEventFormat(const Trace &Records,
 271                                                     raw_ostream &OS) {
 272   const auto &FH = Records.getFileHeader();
 273   auto Version = FH.Version;
 274   auto CycleFreq = FH.CycleFrequency;
 275
 276   unsigned id_counter = 0;
 277
 278   OS << "{\n  \"traceEvents\": [";
 279   DenseMap<uint32_t, StackTrieNode *> StackCursorByThreadId{};
 280   DenseMap<uint32_t, SmallVector<StackTrieNode *, 4>> StackRootsByThreadId{};
 281   DenseMap<unsigned, StackTrieNode *> StacksByStackId{};
 282   std::forward_list<StackTrieNode> NodeStore{};
 283   int loop_count = 0;
 284   for (const auto &R : Records) {
 285     if (loop_count++ == 0)
 286       OS << "\n";
 287     else
 288       OS << ",\n";
 289
 290     // Chrome trace event format always wants data in micros.
 291     // CyclesPerMicro = CycleHertz / 10^6
 292     // TSC / CyclesPerMicro == TSC * 10^6 / CycleHertz == MicroTimestamp
 293     // Could lose some precision here by converting the TSC to a double to
 294     // multiply by the period in micros. 52 bit mantissa is a good start though.
 295     // TODO: Make feature request to Chrome Trace viewer to accept ticks and a
 296     // frequency or do some more involved calculation to avoid dangers of
 297     // conversion.
 298     double EventTimestampUs = double(1000000) / CycleFreq * double(R.TSC);
 299     StackTrieNode *&StackCursor = StackCursorByThreadId[R.TId];
 300     switch (R.Type) {
 301     case RecordTypes::CUSTOM_EVENT:
 302     case RecordTypes::TYPED_EVENT:
 303       // TODO: Support typed and custom event rendering on Chrome Trace Viewer.
 304       break;
 305     case RecordTypes::ENTER:
 306     case RecordTypes::ENTER_ARG:
 307       StackCursor = findOrCreateStackNode(StackCursor, R.FuncId, R.TId,
 308                                           StackRootsByThreadId, StacksByStackId,
 309                                           &id_counter, NodeStore);
 310       // Each record is represented as a json dictionary with function name,
 311       // type of B for begin or E for end, thread id, process id,
 312       // timestamp in microseconds, and a stack frame id. The ids are logged
 313       // in an id dictionary after the events.
 314       writeTraceViewerRecord(Version, OS, R.FuncId, R.TId, R.PId, Symbolize,
 315                              FuncIdHelper, EventTimestampUs, *StackCursor, "B");
 316       break;
 317     case RecordTypes::EXIT:
 318     case RecordTypes::TAIL_EXIT:
 319       // No entries to record end for.
 320       if (StackCursor == nullptr)
 321         break;
 322       // Should we emit an END record anyway or account this condition?
 323       // (And/Or in loop termination below)
 324       StackTrieNode *PreviousCursor = nullptr;
 325       do {
 326         if (PreviousCursor != nullptr) {
 327           OS << ",\n";
 328         }
 329         writeTraceViewerRecord(Version, OS, StackCursor->FuncId, R.TId, R.PId,
 330                                Symbolize, FuncIdHelper, EventTimestampUs,
 331                                *StackCursor, "E");
 332         PreviousCursor = StackCursor;
 333         StackCursor = StackCursor->Parent;
 334       } while (PreviousCursor->FuncId != R.FuncId && StackCursor != nullptr);
 335       break;
 336     }
 337   }
 338   OS << "\n  ],\n"; // Close the Trace Events array.
 339   OS << "  "
 340      << "\"displayTimeUnit\": \"ns\",\n";
 341
 342   // The stackFrames dictionary substantially reduces size of the output file by
 343   // avoiding repeating the entire call stack of function names for each entry.
 344   OS << R"(  "stackFrames": {)";
 345   int stack_frame_count = 0;
 346   for (auto map_iter : StacksByStackId) {
 347     if (stack_frame_count++ == 0)
 348       OS << "\n";
 349     else
 350       OS << ",\n";
 351     OS << "    ";
 352     OS << llvm::formatv(
 353         R"("{0}" : { "name" : "{1}")", map_iter.first,
 354         (Symbolize ? FuncIdHelper.SymbolOrNumber(map_iter.second->FuncId)
 355                    : llvm::to_string(map_iter.second->FuncId)));
 356     if (map_iter.second->Parent != nullptr)
 357       OS << llvm::formatv(R"(, "parent": "{0}")",
 358                           map_iter.second->Parent->ExtraData.id);
 359     OS << " }";
 360   }
 361   OS << "\n  }\n"; // Close the stack frames map.
 362   OS << "}\n";     // Close the JSON entry.
 363 }
 364
 365 namespace llvm {
 366 namespace xray {
 367
 368 static CommandRegistration Unused(&Convert, []() -> Error {
 369   // FIXME: Support conversion to BINARY when upgrading XRay trace versions.
 370   InstrumentationMap Map;
 371   if (!ConvertInstrMap.empty()) {
 372     auto InstrumentationMapOrError = loadInstrumentationMap(ConvertInstrMap);
 373     if (!InstrumentationMapOrError)
 374       return joinErrors(make_error<StringError>(
 375                             Twine("Cannot open instrumentation map '") +
 376                                 ConvertInstrMap + "'",
 377                             std::make_error_code(std::errc::invalid_argument)),
 378                         InstrumentationMapOrError.takeError());
 379     Map = std::move(*InstrumentationMapOrError);
 380   }
 381
 382   const auto &FunctionAddresses = Map.getFunctionAddresses();
 383   symbolize::LLVMSymbolizer Symbolizer;
 384   llvm::xray::FuncIdConversionHelper FuncIdHelper(ConvertInstrMap, Symbolizer,
 385                                                   FunctionAddresses);
 386   llvm::xray::TraceConverter TC(FuncIdHelper, ConvertSymbolize);
 387   std::error_code EC;
 388   raw_fd_ostream OS(ConvertOutput, EC,
 389                     ConvertOutputFormat == ConvertFormats::BINARY
 390                         ? sys::fs::OpenFlags::OF_None
 391                         : sys::fs::OpenFlags::OF_Text);
 392   if (EC)
 393     return make_error<StringError>(
 394         Twine("Cannot open file '") + ConvertOutput + "' for writing.", EC);
 395
 396   auto TraceOrErr = loadTraceFile(ConvertInput, ConvertSortInput);
 397   if (!TraceOrErr)
 398     return joinErrors(
 399         make_error<StringError>(
 400             Twine("Failed loading input file '") + ConvertInput + "'.",
 401             std::make_error_code(std::errc::executable_format_error)),
 402         TraceOrErr.takeError());
 403
 404   auto &T = *TraceOrErr;
 405   switch (ConvertOutputFormat) {
 406   case ConvertFormats::YAML:
 407     TC.exportAsYAML(T, OS);
 408     break;
 409   case ConvertFormats::BINARY:
 410     TC.exportAsRAWv1(T, OS);
 411     break;
 412   case ConvertFormats::CHROME_TRACE_EVENT:
 413     TC.exportAsChromeTraceEventFormat(T, OS);
 414     break;
 415   }
 416   return Error::success();
 417 });
 418
 419 } // namespace xray
 420 } // namespace llvm