Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 606 insertions, 0 deletions

diff --git a/js/src/gc/Statistics.h b/js/src/gc/Statistics.h
new file mode 100644
index 0000000000..0e45cd651a
--- /dev/null
+++ b/js/src/gc/Statistics.h
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef gc_Statistics_h
+#define gc_Statistics_h
+
+#include "mozilla/Array.h"
+#include "mozilla/Atomics.h"
+#include "mozilla/EnumeratedArray.h"
+#include "mozilla/Maybe.h"
+#include "mozilla/TimeStamp.h"
+
+#include "jspubtd.h"
+#include "NamespaceImports.h"
+
+#include "gc/GCEnum.h"
+#include "js/AllocPolicy.h"
+#include "js/GCAPI.h"
+#include "js/SliceBudget.h"
+#include "js/Vector.h"
+
+namespace js {
+
+class JS_PUBLIC_API Sprinter;
+class JSONPrinter;
+
+namespace gcstats {
+
+// Phase data is generated by a script. If you need to add phases, edit
+// js/src/gc/GenerateStatsPhases.py
+
+#include "gc/StatsPhasesGenerated.h"
+
+// Counts can be incremented with Statistics::count(). They're reset at the end
+// of a Major GC.
+enum Count {
+  COUNT_NEW_CHUNK,
+  COUNT_DESTROY_CHUNK,
+  COUNT_MINOR_GC,
+
+  // Number of times a 'put' into a storebuffer overflowed, triggering a
+  // compaction
+  COUNT_STOREBUFFER_OVERFLOW,
+
+  // Number of arenas relocated by compacting GC.
+  COUNT_ARENA_RELOCATED,
+
+  // Number of cells marked during the marking phase. Excludes atoms marked when
+  // not collecting the atoms zone.
+  COUNT_CELLS_MARKED,
+
+  // Number of times work was donated to a requesting thread during parallel
+  // marking.
+  COUNT_PARALLEL_MARK_INTERRUPTIONS,
+
+  COUNT_LIMIT
+};
+
+// Stats can be set with Statistics::setStat(). They're not reset automatically.
+enum Stat {
+  // Number of strings tenured.
+  STAT_STRINGS_TENURED,
+
+  // Number of strings deduplicated.
+  STAT_STRINGS_DEDUPLICATED,
+
+  // Number of BigInts tenured.
+  STAT_BIGINTS_TENURED,
+
+  STAT_LIMIT
+};
+
+struct ZoneGCStats {
+  /* Number of zones collected in this GC. */
+  int collectedZoneCount = 0;
+
+  /* Total number of zones in the Runtime at the start of this GC. */
+  int zoneCount = 0;
+
+  /* Number of zones swept in this GC. */
+  int sweptZoneCount = 0;
+
+  /* Total number of compartments in all zones collected. */
+  int collectedCompartmentCount = 0;
+
+  /* Total number of compartments in the Runtime at the start of this GC. */
+  int compartmentCount = 0;
+
+  /* Total number of compartments swept by this GC. */
+  int sweptCompartmentCount = 0;
+
+  ZoneGCStats() = default;
+};
+
+struct Trigger {
+  size_t amount = 0;
+  size_t threshold = 0;
+};
+
+#define FOR_EACH_GC_PROFILE_TIME(_)                                 \
+  _(Total, "total", PhaseKind::NONE)                                \
+  _(Background, "bgwrk", PhaseKind::NONE)                           \
+  _(BeginCallback, "bgnCB", PhaseKind::GC_BEGIN)                    \
+  _(MinorForMajor, "evct4m", PhaseKind::EVICT_NURSERY_FOR_MAJOR_GC) \
+  _(WaitBgThread, "waitBG", PhaseKind::WAIT_BACKGROUND_THREAD)      \
+  _(Prepare, "prep", PhaseKind::PREPARE)                            \
+  _(Mark, "mark", PhaseKind::MARK)                                  \
+  _(Sweep, "sweep", PhaseKind::SWEEP)                               \
+  _(Compact, "cmpct", PhaseKind::COMPACT)                           \
+  _(EndCallback, "endCB", PhaseKind::GC_END)                        \
+  _(MinorGC, "minor", PhaseKind::MINOR_GC)                          \
+  _(EvictNursery, "evict", PhaseKind::EVICT_NURSERY)
+
+static const char* const MajorGCProfilePrefix = "MajorGC:";
+static const char* const MinorGCProfilePrefix = "MinorGC:";
+
+const char* ExplainAbortReason(GCAbortReason reason);
+
+/*
+ * Struct for collecting timing statistics on a "phase tree". The tree is
+ * specified as a limited DAG, but the timings are collected for the whole tree
+ * that you would get by expanding out the DAG by duplicating subtrees rooted
+ * at nodes with multiple parents.
+ *
+ * During execution, a child phase can be activated multiple times, and the
+ * total time will be accumulated. (So for example, you can start and end
+ * PhaseKind::MARK_ROOTS multiple times before completing the parent phase.)
+ *
+ * Incremental GC is represented by recording separate timing results for each
+ * slice within the overall GC.
+ */
+struct Statistics {
+  template <typename T, size_t Length>
+  using Array = mozilla::Array<T, Length>;
+
+  template <typename IndexType, IndexType SizeAsEnumValue, typename ValueType>
+  using EnumeratedArray =
+      mozilla::EnumeratedArray<IndexType, SizeAsEnumValue, ValueType>;
+
+  using TimeDuration = mozilla::TimeDuration;
+  using TimeStamp = mozilla::TimeStamp;
+
+  // Create types for tables of times, by phase and phase kind.
+  using PhaseTimes = EnumeratedArray<Phase, Phase::LIMIT, TimeDuration>;
+  using PhaseKindTimes =
+      EnumeratedArray<PhaseKind, PhaseKind::LIMIT, TimeDuration>;
+
+  using PhaseTimeStamps = EnumeratedArray<Phase, Phase::LIMIT, TimeStamp>;
+
+  [[nodiscard]] static bool initialize();
+
+  explicit Statistics(gc::GCRuntime* gc);
+  ~Statistics();
+
+  Statistics(const Statistics&) = delete;
+  Statistics& operator=(const Statistics&) = delete;
+
+  void beginPhase(PhaseKind phaseKind);
+  void endPhase(PhaseKind phaseKind);
+  void recordParallelPhase(PhaseKind phaseKind, TimeDuration duration);
+
+  // Occasionally, we may be in the middle of something that is tracked by
+  // this class, and we need to do something unusual (eg evict the nursery)
+  // that doesn't normally nest within the current phase. Suspend the
+  // currently tracked phase stack, at which time the caller is free to do
+  // other tracked operations.
+  //
+  // This also happens internally with the PhaseKind::MUTATOR "phase". While in
+  // this phase, any beginPhase will automatically suspend the non-GC phase,
+  // until that inner stack is complete, at which time it will automatically
+  // resume the non-GC phase. Explicit suspensions do not get auto-resumed.
+  void suspendPhases(PhaseKind suspension = PhaseKind::EXPLICIT_SUSPENSION);
+
+  // Resume a suspended stack of phases.
+  void resumePhases();
+
+  void beginSlice(const ZoneGCStats& zoneStats, JS::GCOptions options,
+                  const SliceBudget& budget, JS::GCReason reason,
+                  bool budgetWasIncreased);
+  void endSlice();
+
+  [[nodiscard]] bool startTimingMutator();
+  [[nodiscard]] bool stopTimingMutator(double& mutator_ms, double& gc_ms);
+
+  // Note when we sweep a zone or compartment.
+  void sweptZone() { ++zoneStats.sweptZoneCount; }
+  void sweptCompartment() { ++zoneStats.sweptCompartmentCount; }
+
+  void reset(GCAbortReason reason) {
+    MOZ_ASSERT(reason != GCAbortReason::None);
+    if (!aborted) {
+      slices_.back().resetReason = reason;
+    }
+  }
+
+  void measureInitialHeapSize();
+
+  void nonincremental(GCAbortReason reason) {
+    MOZ_ASSERT(reason != GCAbortReason::None);
+    nonincrementalReason_ = reason;
+    log("Non-incremental reason: %s", nonincrementalReason());
+  }
+
+  bool nonincremental() const {
+    return nonincrementalReason_ != GCAbortReason::None;
+  }
+
+  const char* nonincrementalReason() const {
+    return ExplainAbortReason(nonincrementalReason_);
+  }
+
+  void count(Count s) { counts[s]++; }
+  void addCount(Count s, uint32_t count) { counts[s] += count; }
+
+  uint32_t getCount(Count s) const { return uint32_t(counts[s]); }
+
+  void setStat(Stat s, uint32_t value) { stats[s] = value; }
+
+  uint32_t getStat(Stat s) const { return stats[s]; }
+
+  void recordTrigger(size_t amount, size_t threshold) {
+    recordedTrigger = mozilla::Some(Trigger{amount, threshold});
+  }
+  bool hasTrigger() const { return recordedTrigger.isSome(); }
+
+  // tenured allocs don't include nursery evictions.
+  void setAllocsSinceMinorGCTenured(uint32_t allocs) {
+    tenuredAllocsSinceMinorGC = allocs;
+  }
+
+  uint32_t allocsSinceMinorGCTenured() { return tenuredAllocsSinceMinorGC; }
+
+  void beginNurseryCollection(JS::GCReason reason);
+  void endNurseryCollection(JS::GCReason reason);
+
+  TimeStamp beginSCC();
+  void endSCC(unsigned scc, TimeStamp start);
+
+  UniqueChars formatCompactSliceMessage() const;
+  UniqueChars formatCompactSummaryMessage() const;
+  UniqueChars formatDetailedMessage() const;
+
+  JS::GCSliceCallback setSliceCallback(JS::GCSliceCallback callback);
+  JS::GCNurseryCollectionCallback setNurseryCollectionCallback(
+      JS::GCNurseryCollectionCallback callback);
+
+  TimeDuration clearMaxGCPauseAccumulator();
+  TimeDuration getMaxGCPauseSinceClear();
+
+  PhaseKind currentPhaseKind() const;
+
+  static const size_t MAX_SUSPENDED_PHASES = MAX_PHASE_NESTING * 3;
+
+  struct SliceData {
+    SliceData(const SliceBudget& budget, mozilla::Maybe<Trigger> trigger,
+              JS::GCReason reason, TimeStamp start, size_t startFaults,
+              gc::State initialState);
+
+    SliceBudget budget;
+    JS::GCReason reason = JS::GCReason::NO_REASON;
+    mozilla::Maybe<Trigger> trigger;
+    gc::State initialState = gc::State::NotActive;
+    gc::State finalState = gc::State::NotActive;
+    GCAbortReason resetReason = GCAbortReason::None;
+    TimeStamp start;
+    TimeStamp end;
+    size_t startFaults = 0;
+    size_t endFaults = 0;
+    PhaseTimes phaseTimes;
+    PhaseKindTimes totalParallelTimes;
+    PhaseKindTimes maxParallelTimes;
+
+    TimeDuration duration() const { return end - start; }
+    bool wasReset() const { return resetReason != GCAbortReason::None; }
+  };
+
+  typedef Vector<SliceData, 8, SystemAllocPolicy> SliceDataVector;
+
+  const SliceDataVector& slices() const { return slices_; }
+
+  const SliceData* lastSlice() const {
+    if (slices_.length() == 0) {
+      return nullptr;
+    }
+
+    return &slices_.back();
+  }
+
+  TimeStamp start() const { return slices_[0].start; }
+
+  TimeStamp end() const { return slices_.back().end; }
+
+  TimeStamp creationTime() const { return creationTime_; }
+
+  TimeDuration totalGCTime() const { return totalGCTime_; }
+  size_t initialCollectedBytes() const { return preCollectedHeapBytes; }
+
+  // File to write profiling information to, either stderr or file specified
+  // with JS_GC_PROFILE_FILE.
+  FILE* profileFile() const { return gcProfileFile; }
+
+  // Occasionally print header lines for profiling information.
+  void maybePrintProfileHeaders();
+
+  // Print header line for profile times.
+  void printProfileHeader();
+
+  // Print total profile times on shutdown.
+  void printTotalProfileTimes();
+
+  // These JSON strings are used by the firefox profiler to display the GC
+  // markers.
+
+  // Return JSON for a whole major GC
+  UniqueChars renderJsonMessage() const;
+
+  // Return JSON for the timings of just the given slice.
+  UniqueChars renderJsonSlice(size_t sliceNum) const;
+
+  // Return JSON for the previous nursery collection.
+  UniqueChars renderNurseryJson() const;
+
+#ifdef DEBUG
+  // Print a logging message.
+  void log(const char* fmt, ...);
+#else
+  void log(const char* fmt, ...){};
+#endif
+
+ private:
+  gc::GCRuntime* const gc;
+
+  /* File used for MOZ_GCTIMER output. */
+  FILE* gcTimerFile;
+
+  /* File used for JS_GC_DEBUG output. */
+  FILE* gcDebugFile;
+
+  /* File used for JS_GC_PROFILE output. */
+  FILE* gcProfileFile;
+
+  ZoneGCStats zoneStats;
+
+  JS::GCOptions gcOptions;
+
+  GCAbortReason nonincrementalReason_;
+
+  SliceDataVector slices_;
+
+  /* Most recent time when the given phase started. */
+  PhaseTimeStamps phaseStartTimes;
+
+#ifdef DEBUG
+  /* Most recent time when the given phase ended. */
+  PhaseTimeStamps phaseEndTimes;
+#endif
+
+  TimeStamp creationTime_;
+
+  /* Bookkeeping for GC timings when timingMutator is true */
+  TimeStamp timedGCStart;
+  TimeDuration timedGCTime;
+
+  /* Total main thread time in a given phase for this GC. */
+  PhaseTimes phaseTimes;
+
+  /* Total main thread time for this GC. */
+  TimeDuration totalGCTime_;
+
+  /* Number of events of this type for this GC. */
+  EnumeratedArray<Count, COUNT_LIMIT,
+                  mozilla::Atomic<uint32_t, mozilla::ReleaseAcquire>>
+      counts;
+
+  /* Other GC statistics. */
+  EnumeratedArray<Stat, STAT_LIMIT, uint32_t> stats;
+
+  /*
+   * These events cannot be kept in the above array, we need to take their
+   * address.
+   */
+  uint32_t tenuredAllocsSinceMinorGC;
+
+  /* Total GC heap size before and after the GC ran. */
+  size_t preTotalHeapBytes;
+  size_t postTotalHeapBytes;
+
+  /* GC heap size for collected zones before GC ran. */
+  size_t preCollectedHeapBytes;
+
+  /*
+   * If a GC slice was triggered by exceeding some threshold, record the
+   * threshold and the value that exceeded it. This happens before the slice
+   * starts so this is recorded here first and then transferred to SliceData.
+   */
+  mozilla::Maybe<Trigger> recordedTrigger;
+
+  /* GC numbers as of the beginning of the collection. */
+  uint64_t startingMinorGCNumber;
+  uint64_t startingMajorGCNumber;
+  uint64_t startingSliceNumber;
+
+  /* Records the maximum GC pause in an API-controlled interval. */
+  mutable TimeDuration maxPauseInInterval;
+
+  /* Phases that are currently on stack. */
+  Vector<Phase, MAX_PHASE_NESTING, SystemAllocPolicy> phaseStack;
+
+  /*
+   * Certain phases can interrupt the phase stack, eg callback phases. When
+   * this happens, we move the suspended phases over to a sepearate list,
+   * terminated by a dummy PhaseKind::SUSPENSION phase (so that we can nest
+   * suspensions by suspending multiple stacks with a PhaseKind::SUSPENSION in
+   * between).
+   */
+  Vector<Phase, MAX_SUSPENDED_PHASES, SystemAllocPolicy> suspendedPhases;
+
+  /* Sweep times for SCCs of compartments. */
+  Vector<TimeDuration, 0, SystemAllocPolicy> sccTimes;
+
+  TimeDuration timeSinceLastGC;
+
+  JS::GCSliceCallback sliceCallback;
+  JS::GCNurseryCollectionCallback nurseryCollectionCallback;
+
+  /*
+   * True if we saw an OOM while allocating slices or we saw an impossible
+   * timestamp. The statistics for this GC will be invalid.
+   */
+  bool aborted;
+
+  /* Profiling data. */
+
+  enum class ProfileKey {
+#define DEFINE_PROFILE_KEY(name, _1, _2) name,
+    FOR_EACH_GC_PROFILE_TIME(DEFINE_PROFILE_KEY)
+#undef DEFINE_PROFILE_KEY
+        KeyCount
+  };
+
+  using ProfileDurations =
+      EnumeratedArray<ProfileKey, ProfileKey::KeyCount, TimeDuration>;
+
+  bool enableProfiling_;
+  bool profileWorkers_;
+  TimeDuration profileThreshold_;
+  ProfileDurations totalTimes_;
+  uint64_t sliceCount_;
+
+  char formatBuffer_[32];
+  static constexpr int FormatBufferLength = sizeof(formatBuffer_);
+
+  JSContext* context();
+
+  Phase currentPhase() const;
+  Phase lookupChildPhase(PhaseKind phaseKind) const;
+
+  void beginGC(JS::GCOptions options, const TimeStamp& currentTime);
+  void endGC();
+
+  void sendGCTelemetry();
+  void sendSliceTelemetry(const SliceData& slice);
+
+  TimeDuration sumTotalParallelTime(PhaseKind phaseKind) const;
+
+  void recordPhaseBegin(Phase phase);
+  void recordPhaseEnd(Phase phase);
+
+  void gcDuration(TimeDuration* total, TimeDuration* maxPause) const;
+  void sccDurations(TimeDuration* total, TimeDuration* maxPause) const;
+  void printStats();
+
+  template <typename Fn>
+  void reportLongestPhaseInMajorGC(PhaseKind longest, Fn reportFn);
+
+  UniqueChars formatCompactSlicePhaseTimes(const PhaseTimes& phaseTimes) const;
+
+  UniqueChars formatDetailedDescription() const;
+  UniqueChars formatDetailedSliceDescription(unsigned i,
+                                             const SliceData& slice) const;
+  UniqueChars formatDetailedPhaseTimes(const PhaseTimes& phaseTimes) const;
+  UniqueChars formatDetailedTotals() const;
+
+  void formatJsonDescription(JSONPrinter&) const;
+  void formatJsonSliceDescription(unsigned i, const SliceData& slice,
+                                  JSONPrinter&) const;
+  void formatJsonPhaseTimes(const PhaseTimes& phaseTimes, JSONPrinter&) const;
+  void formatJsonSlice(size_t sliceNum, JSONPrinter&) const;
+
+  double computeMMU(TimeDuration resolution) const;
+
+  void printSliceProfile();
+  ProfileDurations getProfileTimes(const SliceData& slice) const;
+  void updateTotalProfileTimes(const ProfileDurations& times);
+  const char* formatGCStates(const SliceData& slice);
+  const char* formatGCFlags(const SliceData& slice);
+  const char* formatBudget(const SliceData& slice);
+  const char* formatTotalSlices();
+  static bool printProfileTimes(const ProfileDurations& times,
+                                Sprinter& sprinter);
+};
+
+struct MOZ_RAII AutoGCSlice {
+  AutoGCSlice(Statistics& stats, const ZoneGCStats& zoneStats,
+              JS::GCOptions options, const SliceBudget& budget,
+              JS::GCReason reason, bool budgetWasIncreased)
+      : stats(stats) {
+    stats.beginSlice(zoneStats, options, budget, reason, budgetWasIncreased);
+  }
+  ~AutoGCSlice() { stats.endSlice(); }
+
+  Statistics& stats;
+};
+
+struct MOZ_RAII AutoPhase {
+  AutoPhase(Statistics& stats, PhaseKind phaseKind)
+      : stats(stats), phaseKind(phaseKind), enabled(true) {
+    stats.beginPhase(phaseKind);
+  }
+
+  AutoPhase(Statistics& stats, bool condition, PhaseKind phaseKind)
+      : stats(stats), phaseKind(phaseKind), enabled(condition) {
+    if (enabled) {
+      stats.beginPhase(phaseKind);
+    }
+  }
+
+  ~AutoPhase() {
+    if (enabled) {
+      stats.endPhase(phaseKind);
+    }
+  }
+
+  Statistics& stats;
+  PhaseKind phaseKind;
+  bool enabled;
+};
+
+struct MOZ_RAII AutoSCC {
+  AutoSCC(Statistics& stats, unsigned scc) : stats(stats), scc(scc) {
+    start = stats.beginSCC();
+  }
+  ~AutoSCC() { stats.endSCC(scc, start); }
+
+  Statistics& stats;
+  unsigned scc;
+  mozilla::TimeStamp start;
+};
+
+void ReadProfileEnv(const char* envName, const char* helpText, bool* enableOut,
+                    bool* workersOut, mozilla::TimeDuration* thresholdOut);
+
+} /* namespace gcstats */
+
+struct StringStats {
+  // number of strings that were deduplicated, and their sizes in characters
+  // and bytes
+  uint64_t deduplicatedStrings = 0;
+  uint64_t deduplicatedChars = 0;
+  uint64_t deduplicatedBytes = 0;
+
+  // number of live nursery strings at the start of a nursery collection
+  uint64_t liveNurseryStrings = 0;
+
+  // number of new strings added to the tenured heap
+  uint64_t tenuredStrings = 0;
+
+  // Currently, liveNurseryStrings = tenuredStrings + deduplicatedStrings (but
+  // in the future we may do more transformation during tenuring, eg
+  // atomizing.)
+
+  // number of malloced bytes associated with tenured strings (the actual
+  // malloc will have happened when the strings were allocated in the nursery;
+  // the ownership of the bytes will be transferred to the tenured strings)
+  uint64_t tenuredBytes = 0;
+
+  StringStats& operator+=(const StringStats& other) {
+    deduplicatedStrings += other.deduplicatedStrings;
+    deduplicatedChars += other.deduplicatedChars;
+    deduplicatedBytes += other.deduplicatedBytes;
+    liveNurseryStrings += other.liveNurseryStrings;
+    tenuredStrings += other.tenuredStrings;
+    tenuredBytes += other.tenuredBytes;
+    return *this;
+  }
+
+  void noteTenured(size_t mallocBytes) {
+    liveNurseryStrings++;
+    tenuredStrings++;
+    tenuredBytes += mallocBytes;
+  }
+
+  void noteDeduplicated(size_t numChars, size_t mallocBytes) {
+    liveNurseryStrings++;
+    deduplicatedStrings++;
+    deduplicatedChars += numChars;
+    deduplicatedBytes += mallocBytes;
+  }
+};
+
+} /* namespace js */
+
+#endif /* gc_Statistics_h */