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Diffstat (limited to 'tools/profiler/core/ProfileBufferEntry.cpp')
| -rw-r--r-- | tools/profiler/core/ProfileBufferEntry.cpp | 2321 |
1 files changed, 2321 insertions, 0 deletions
diff --git a/tools/profiler/core/ProfileBufferEntry.cpp b/tools/profiler/core/ProfileBufferEntry.cpp new file mode 100644 index 0000000000..5429eac0b8 --- /dev/null +++ b/tools/profiler/core/ProfileBufferEntry.cpp @@ -0,0 +1,2321 @@ +/* -*- 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/. */ + +#include "ProfileBufferEntry.h" + +#include "mozilla/ProfilerMarkers.h" +#include "platform.h" +#include "ProfileBuffer.h" +#include "ProfiledThreadData.h" +#include "ProfilerBacktrace.h" +#include "ProfilerRustBindings.h" + +#include "js/ProfilingFrameIterator.h" +#include "jsapi.h" +#include "jsfriendapi.h" +#include "mozilla/Logging.h" +#include "mozilla/JSONStringWriteFuncs.h" +#include "mozilla/ScopeExit.h" +#include "mozilla/Sprintf.h" +#include "mozilla/StackWalk.h" +#include "nsThreadUtils.h" +#include "nsXULAppAPI.h" +#include "ProfilerCodeAddressService.h" + +#include <ostream> +#include <type_traits> + +using namespace mozilla; +using namespace mozilla::literals::ProportionValue_literals; + +//////////////////////////////////////////////////////////////////////// +// BEGIN ProfileBufferEntry + +ProfileBufferEntry::ProfileBufferEntry() + : mKind(Kind::INVALID), mStorage{0, 0, 0, 0, 0, 0, 0, 0} {} + +// aString must be a static string. +ProfileBufferEntry::ProfileBufferEntry(Kind aKind, const char* aString) + : mKind(aKind) { + MOZ_ASSERT(aKind == Kind::Label); + memcpy(mStorage, &aString, sizeof(aString)); +} + +ProfileBufferEntry::ProfileBufferEntry(Kind aKind, char aChars[kNumChars]) + : mKind(aKind) { + MOZ_ASSERT(aKind == Kind::DynamicStringFragment); + memcpy(mStorage, aChars, kNumChars); +} + +ProfileBufferEntry::ProfileBufferEntry(Kind aKind, void* aPtr) : mKind(aKind) { + memcpy(mStorage, &aPtr, sizeof(aPtr)); +} + +ProfileBufferEntry::ProfileBufferEntry(Kind aKind, double aDouble) + : mKind(aKind) { + memcpy(mStorage, &aDouble, sizeof(aDouble)); +} + +ProfileBufferEntry::ProfileBufferEntry(Kind aKind, int aInt) : mKind(aKind) { + memcpy(mStorage, &aInt, sizeof(aInt)); +} + +ProfileBufferEntry::ProfileBufferEntry(Kind aKind, int64_t aInt64) + : mKind(aKind) { + memcpy(mStorage, &aInt64, sizeof(aInt64)); +} + +ProfileBufferEntry::ProfileBufferEntry(Kind aKind, uint64_t aUint64) + : mKind(aKind) { + memcpy(mStorage, &aUint64, sizeof(aUint64)); +} + +ProfileBufferEntry::ProfileBufferEntry(Kind aKind, ProfilerThreadId aThreadId) + : mKind(aKind) { + static_assert(std::is_trivially_copyable_v<ProfilerThreadId>); + static_assert(sizeof(aThreadId) <= sizeof(mStorage)); + memcpy(mStorage, &aThreadId, sizeof(aThreadId)); +} + +const char* ProfileBufferEntry::GetString() const { + const char* result; + memcpy(&result, mStorage, sizeof(result)); + return result; +} + +void* ProfileBufferEntry::GetPtr() const { + void* result; + memcpy(&result, mStorage, sizeof(result)); + return result; +} + +double ProfileBufferEntry::GetDouble() const { + double result; + memcpy(&result, mStorage, sizeof(result)); + return result; +} + +int ProfileBufferEntry::GetInt() const { + int result; + memcpy(&result, mStorage, sizeof(result)); + return result; +} + +int64_t ProfileBufferEntry::GetInt64() const { + int64_t result; + memcpy(&result, mStorage, sizeof(result)); + return result; +} + +uint64_t ProfileBufferEntry::GetUint64() const { + uint64_t result; + memcpy(&result, mStorage, sizeof(result)); + return result; +} + +ProfilerThreadId ProfileBufferEntry::GetThreadId() const { + ProfilerThreadId result; + static_assert(std::is_trivially_copyable_v<ProfilerThreadId>); + memcpy(&result, mStorage, sizeof(result)); + return result; +} + +void ProfileBufferEntry::CopyCharsInto(char (&aOutArray)[kNumChars]) const { + memcpy(aOutArray, mStorage, kNumChars); +} + +// END ProfileBufferEntry +//////////////////////////////////////////////////////////////////////// + +struct TypeInfo { + Maybe<nsCString> mKeyedBy; + Maybe<nsCString> mName; + Maybe<nsCString> mLocation; + Maybe<unsigned> mLineNumber; +}; + +// As mentioned in ProfileBufferEntry.h, the JSON format contains many +// arrays whose elements are laid out according to various schemas to help +// de-duplication. This RAII class helps write these arrays by keeping track of +// the last non-null element written and adding the appropriate number of null +// elements when writing new non-null elements. It also automatically opens and +// closes an array element on the given JSON writer. +// +// You grant the AutoArraySchemaWriter exclusive access to the JSONWriter and +// the UniqueJSONStrings objects for the lifetime of AutoArraySchemaWriter. Do +// not access them independently while the AutoArraySchemaWriter is alive. +// If you need to add complex objects, call FreeFormElement(), which will give +// you temporary access to the writer. +// +// Example usage: +// +// // Define the schema of elements in this type of array: [FOO, BAR, BAZ] +// enum Schema : uint32_t { +// FOO = 0, +// BAR = 1, +// BAZ = 2 +// }; +// +// AutoArraySchemaWriter writer(someJsonWriter, someUniqueStrings); +// if (shouldWriteFoo) { +// writer.IntElement(FOO, getFoo()); +// } +// ... etc ... +// +// The elements need to be added in-order. +class MOZ_RAII AutoArraySchemaWriter { + public: + explicit AutoArraySchemaWriter(SpliceableJSONWriter& aWriter) + : mJSONWriter(aWriter), mNextFreeIndex(0) { + mJSONWriter.StartArrayElement(); + } + + ~AutoArraySchemaWriter() { mJSONWriter.EndArray(); } + + template <typename T> + void IntElement(uint32_t aIndex, T aValue) { + static_assert(!std::is_same_v<T, uint64_t>, + "Narrowing uint64 -> int64 conversion not allowed"); + FillUpTo(aIndex); + mJSONWriter.IntElement(static_cast<int64_t>(aValue)); + } + + void DoubleElement(uint32_t aIndex, double aValue) { + FillUpTo(aIndex); + mJSONWriter.DoubleElement(aValue); + } + + void TimeMsElement(uint32_t aIndex, double aTime_ms) { + FillUpTo(aIndex); + mJSONWriter.TimeDoubleMsElement(aTime_ms); + } + + void BoolElement(uint32_t aIndex, bool aValue) { + FillUpTo(aIndex); + mJSONWriter.BoolElement(aValue); + } + + protected: + SpliceableJSONWriter& Writer() { return mJSONWriter; } + + void FillUpTo(uint32_t aIndex) { + MOZ_ASSERT(aIndex >= mNextFreeIndex); + mJSONWriter.NullElements(aIndex - mNextFreeIndex); + mNextFreeIndex = aIndex + 1; + } + + private: + SpliceableJSONWriter& mJSONWriter; + uint32_t mNextFreeIndex; +}; + +// Same as AutoArraySchemaWriter, but this can also write strings (output as +// indexes into the table of unique strings). +class MOZ_RAII AutoArraySchemaWithStringsWriter : public AutoArraySchemaWriter { + public: + AutoArraySchemaWithStringsWriter(SpliceableJSONWriter& aWriter, + UniqueJSONStrings& aStrings) + : AutoArraySchemaWriter(aWriter), mStrings(aStrings) {} + + void StringElement(uint32_t aIndex, const Span<const char>& aValue) { + FillUpTo(aIndex); + mStrings.WriteElement(Writer(), aValue); + } + + private: + UniqueJSONStrings& mStrings; +}; + +Maybe<UniqueStacks::StackKey> UniqueStacks::BeginStack(const FrameKey& aFrame) { + if (Maybe<uint32_t> frameIndex = GetOrAddFrameIndex(aFrame); frameIndex) { + return Some(StackKey(*frameIndex)); + } + return Nothing{}; +} + +Vector<JITFrameInfoForBufferRange>&& +JITFrameInfo::MoveRangesWithNewFailureLatch(FailureLatch& aFailureLatch) && { + aFailureLatch.SetFailureFrom(mLocalFailureLatchSource); + return std::move(mRanges); +} + +UniquePtr<UniqueJSONStrings>&& +JITFrameInfo::MoveUniqueStringsWithNewFailureLatch( + FailureLatch& aFailureLatch) && { + if (mUniqueStrings) { + mUniqueStrings->ChangeFailureLatchAndForwardState(aFailureLatch); + } else { + aFailureLatch.SetFailureFrom(mLocalFailureLatchSource); + } + return std::move(mUniqueStrings); +} + +Maybe<UniqueStacks::StackKey> UniqueStacks::AppendFrame( + const StackKey& aStack, const FrameKey& aFrame) { + if (Maybe<uint32_t> stackIndex = GetOrAddStackIndex(aStack); stackIndex) { + if (Maybe<uint32_t> frameIndex = GetOrAddFrameIndex(aFrame); frameIndex) { + return Some(StackKey(aStack, *stackIndex, *frameIndex)); + } + } + return Nothing{}; +} + +JITFrameInfoForBufferRange JITFrameInfoForBufferRange::Clone() const { + JITFrameInfoForBufferRange::JITAddressToJITFramesMap jitAddressToJITFramesMap; + MOZ_RELEASE_ASSERT( + jitAddressToJITFramesMap.reserve(mJITAddressToJITFramesMap.count())); + for (auto iter = mJITAddressToJITFramesMap.iter(); !iter.done(); + iter.next()) { + const mozilla::Vector<JITFrameKey>& srcKeys = iter.get().value(); + mozilla::Vector<JITFrameKey> destKeys; + MOZ_RELEASE_ASSERT(destKeys.appendAll(srcKeys)); + jitAddressToJITFramesMap.putNewInfallible(iter.get().key(), + std::move(destKeys)); + } + + JITFrameInfoForBufferRange::JITFrameToFrameJSONMap jitFrameToFrameJSONMap; + MOZ_RELEASE_ASSERT( + jitFrameToFrameJSONMap.reserve(mJITFrameToFrameJSONMap.count())); + for (auto iter = mJITFrameToFrameJSONMap.iter(); !iter.done(); iter.next()) { + jitFrameToFrameJSONMap.putNewInfallible(iter.get().key(), + iter.get().value()); + } + + return JITFrameInfoForBufferRange{mRangeStart, mRangeEnd, + std::move(jitAddressToJITFramesMap), + std::move(jitFrameToFrameJSONMap)}; +} + +JITFrameInfo::JITFrameInfo(const JITFrameInfo& aOther, + mozilla::ProgressLogger aProgressLogger) + : mUniqueStrings(MakeUniqueFallible<UniqueJSONStrings>( + mLocalFailureLatchSource, *aOther.mUniqueStrings, + aProgressLogger.CreateSubLoggerFromTo( + 0_pc, "Creating JIT frame info unique strings...", 49_pc, + "Created JIT frame info unique strings"))) { + if (!mUniqueStrings) { + mLocalFailureLatchSource.SetFailure( + "OOM in JITFrameInfo allocating mUniqueStrings"); + return; + } + + if (mRanges.reserve(aOther.mRanges.length())) { + for (auto&& [i, progressLogger] : + aProgressLogger.CreateLoopSubLoggersFromTo(50_pc, 100_pc, + aOther.mRanges.length(), + "Copying JIT frame info")) { + mRanges.infallibleAppend(aOther.mRanges[i].Clone()); + } + } else { + mLocalFailureLatchSource.SetFailure("OOM in JITFrameInfo resizing mRanges"); + } +} + +bool UniqueStacks::FrameKey::NormalFrameData::operator==( + const NormalFrameData& aOther) const { + return mLocation == aOther.mLocation && + mRelevantForJS == aOther.mRelevantForJS && + mBaselineInterp == aOther.mBaselineInterp && + mInnerWindowID == aOther.mInnerWindowID && mLine == aOther.mLine && + mColumn == aOther.mColumn && mCategoryPair == aOther.mCategoryPair; +} + +bool UniqueStacks::FrameKey::JITFrameData::operator==( + const JITFrameData& aOther) const { + return mCanonicalAddress == aOther.mCanonicalAddress && + mDepth == aOther.mDepth && mRangeIndex == aOther.mRangeIndex; +} + +// Consume aJITFrameInfo by stealing its string table and its JIT frame info +// ranges. The JIT frame info contains JSON which refers to strings from the +// JIT frame info's string table, so our string table needs to have the same +// strings at the same indices. +UniqueStacks::UniqueStacks( + FailureLatch& aFailureLatch, JITFrameInfo&& aJITFrameInfo, + ProfilerCodeAddressService* aCodeAddressService /* = nullptr */) + : mUniqueStrings(std::move(aJITFrameInfo) + .MoveUniqueStringsWithNewFailureLatch(aFailureLatch)), + mCodeAddressService(aCodeAddressService), + mFrameTableWriter(aFailureLatch), + mStackTableWriter(aFailureLatch), + mJITInfoRanges(std::move(aJITFrameInfo) + .MoveRangesWithNewFailureLatch(aFailureLatch)) { + if (!mUniqueStrings) { + SetFailure("Did not get mUniqueStrings from JITFrameInfo"); + return; + } + + mFrameTableWriter.StartBareList(); + mStackTableWriter.StartBareList(); +} + +Maybe<uint32_t> UniqueStacks::GetOrAddStackIndex(const StackKey& aStack) { + if (Failed()) { + return Nothing{}; + } + + uint32_t count = mStackToIndexMap.count(); + auto entry = mStackToIndexMap.lookupForAdd(aStack); + if (entry) { + MOZ_ASSERT(entry->value() < count); + return Some(entry->value()); + } + + if (!mStackToIndexMap.add(entry, aStack, count)) { + SetFailure("OOM in UniqueStacks::GetOrAddStackIndex"); + return Nothing{}; + } + StreamStack(aStack); + return Some(count); +} + +Maybe<Vector<UniqueStacks::FrameKey>> +UniqueStacks::LookupFramesForJITAddressFromBufferPos(void* aJITAddress, + uint64_t aBufferPos) { + JITFrameInfoForBufferRange* rangeIter = + std::lower_bound(mJITInfoRanges.begin(), mJITInfoRanges.end(), aBufferPos, + [](const JITFrameInfoForBufferRange& aRange, + uint64_t aPos) { return aRange.mRangeEnd < aPos; }); + MOZ_RELEASE_ASSERT( + rangeIter != mJITInfoRanges.end() && + rangeIter->mRangeStart <= aBufferPos && + aBufferPos < rangeIter->mRangeEnd, + "Buffer position of jit address needs to be in one of the ranges"); + + using JITFrameKey = JITFrameInfoForBufferRange::JITFrameKey; + + const JITFrameInfoForBufferRange& jitFrameInfoRange = *rangeIter; + auto jitFrameKeys = + jitFrameInfoRange.mJITAddressToJITFramesMap.lookup(aJITAddress); + if (!jitFrameKeys) { + return Nothing(); + } + + // Map the array of JITFrameKeys to an array of FrameKeys, and ensure that + // each of the FrameKeys exists in mFrameToIndexMap. + Vector<FrameKey> frameKeys; + MOZ_RELEASE_ASSERT(frameKeys.initCapacity(jitFrameKeys->value().length())); + for (const JITFrameKey& jitFrameKey : jitFrameKeys->value()) { + FrameKey frameKey(jitFrameKey.mCanonicalAddress, jitFrameKey.mDepth, + rangeIter - mJITInfoRanges.begin()); + uint32_t index = mFrameToIndexMap.count(); + auto entry = mFrameToIndexMap.lookupForAdd(frameKey); + if (!entry) { + // We need to add this frame to our frame table. The JSON for this frame + // already exists in jitFrameInfoRange, we just need to splice it into + // the frame table and give it an index. + auto frameJSON = + jitFrameInfoRange.mJITFrameToFrameJSONMap.lookup(jitFrameKey); + MOZ_RELEASE_ASSERT(frameJSON, "Should have cached JSON for this frame"); + mFrameTableWriter.Splice(frameJSON->value()); + MOZ_RELEASE_ASSERT(mFrameToIndexMap.add(entry, frameKey, index)); + } + MOZ_RELEASE_ASSERT(frameKeys.append(std::move(frameKey))); + } + return Some(std::move(frameKeys)); +} + +Maybe<uint32_t> UniqueStacks::GetOrAddFrameIndex(const FrameKey& aFrame) { + if (Failed()) { + return Nothing{}; + } + + uint32_t count = mFrameToIndexMap.count(); + auto entry = mFrameToIndexMap.lookupForAdd(aFrame); + if (entry) { + MOZ_ASSERT(entry->value() < count); + return Some(entry->value()); + } + + if (!mFrameToIndexMap.add(entry, aFrame, count)) { + SetFailure("OOM in UniqueStacks::GetOrAddFrameIndex"); + return Nothing{}; + } + StreamNonJITFrame(aFrame); + return Some(count); +} + +void UniqueStacks::SpliceFrameTableElements(SpliceableJSONWriter& aWriter) { + mFrameTableWriter.EndBareList(); + aWriter.TakeAndSplice(mFrameTableWriter.TakeChunkedWriteFunc()); +} + +void UniqueStacks::SpliceStackTableElements(SpliceableJSONWriter& aWriter) { + mStackTableWriter.EndBareList(); + aWriter.TakeAndSplice(mStackTableWriter.TakeChunkedWriteFunc()); +} + +[[nodiscard]] nsAutoCString UniqueStacks::FunctionNameOrAddress(void* aPC) { + nsAutoCString nameOrAddress; + + if (!mCodeAddressService || + !mCodeAddressService->GetFunction(aPC, nameOrAddress) || + nameOrAddress.IsEmpty()) { + nameOrAddress.AppendASCII("0x"); + // `AppendInt` only knows `uint32_t` or `uint64_t`, but because these are + // just aliases for *two* of (`unsigned`, `unsigned long`, and `unsigned + // long long`), a call with `uintptr_t` could use the third type and + // therefore would be ambiguous. + // So we want to force using exactly `uint32_t` or `uint64_t`, whichever + // matches the size of `uintptr_t`. + // (The outer cast to `uint` should then be a no-op.) + using uint = std::conditional_t<sizeof(uintptr_t) <= sizeof(uint32_t), + uint32_t, uint64_t>; + nameOrAddress.AppendInt(static_cast<uint>(reinterpret_cast<uintptr_t>(aPC)), + 16); + } + + return nameOrAddress; +} + +void UniqueStacks::StreamStack(const StackKey& aStack) { + enum Schema : uint32_t { PREFIX = 0, FRAME = 1 }; + + AutoArraySchemaWriter writer(mStackTableWriter); + if (aStack.mPrefixStackIndex.isSome()) { + writer.IntElement(PREFIX, *aStack.mPrefixStackIndex); + } + writer.IntElement(FRAME, aStack.mFrameIndex); +} + +void UniqueStacks::StreamNonJITFrame(const FrameKey& aFrame) { + if (Failed()) { + return; + } + + using NormalFrameData = FrameKey::NormalFrameData; + + enum Schema : uint32_t { + LOCATION = 0, + RELEVANT_FOR_JS = 1, + INNER_WINDOW_ID = 2, + IMPLEMENTATION = 3, + LINE = 4, + COLUMN = 5, + CATEGORY = 6, + SUBCATEGORY = 7 + }; + + AutoArraySchemaWithStringsWriter writer(mFrameTableWriter, *mUniqueStrings); + + const NormalFrameData& data = aFrame.mData.as<NormalFrameData>(); + writer.StringElement(LOCATION, data.mLocation); + writer.BoolElement(RELEVANT_FOR_JS, data.mRelevantForJS); + + // It's okay to convert uint64_t to double here because DOM always creates IDs + // that are convertible to double. + writer.DoubleElement(INNER_WINDOW_ID, data.mInnerWindowID); + + // The C++ interpreter is the default implementation so we only emit element + // for Baseline Interpreter frames. + if (data.mBaselineInterp) { + writer.StringElement(IMPLEMENTATION, MakeStringSpan("blinterp")); + } + + if (data.mLine.isSome()) { + writer.IntElement(LINE, *data.mLine); + } + if (data.mColumn.isSome()) { + writer.IntElement(COLUMN, *data.mColumn); + } + if (data.mCategoryPair.isSome()) { + const JS::ProfilingCategoryPairInfo& info = + JS::GetProfilingCategoryPairInfo(*data.mCategoryPair); + writer.IntElement(CATEGORY, uint32_t(info.mCategory)); + writer.IntElement(SUBCATEGORY, info.mSubcategoryIndex); + } +} + +static void StreamJITFrame(JSContext* aContext, SpliceableJSONWriter& aWriter, + UniqueJSONStrings& aUniqueStrings, + const JS::ProfiledFrameHandle& aJITFrame) { + enum Schema : uint32_t { + LOCATION = 0, + RELEVANT_FOR_JS = 1, + INNER_WINDOW_ID = 2, + IMPLEMENTATION = 3, + LINE = 4, + COLUMN = 5, + CATEGORY = 6, + SUBCATEGORY = 7 + }; + + AutoArraySchemaWithStringsWriter writer(aWriter, aUniqueStrings); + + writer.StringElement(LOCATION, MakeStringSpan(aJITFrame.label())); + writer.BoolElement(RELEVANT_FOR_JS, false); + + // It's okay to convert uint64_t to double here because DOM always creates IDs + // that are convertible to double. + // Realm ID is the name of innerWindowID inside JS code. + writer.DoubleElement(INNER_WINDOW_ID, aJITFrame.realmID()); + + JS::ProfilingFrameIterator::FrameKind frameKind = aJITFrame.frameKind(); + MOZ_ASSERT(frameKind == JS::ProfilingFrameIterator::Frame_Ion || + frameKind == JS::ProfilingFrameIterator::Frame_Baseline); + writer.StringElement(IMPLEMENTATION, + frameKind == JS::ProfilingFrameIterator::Frame_Ion + ? MakeStringSpan("ion") + : MakeStringSpan("baseline")); + + const JS::ProfilingCategoryPairInfo& info = JS::GetProfilingCategoryPairInfo( + frameKind == JS::ProfilingFrameIterator::Frame_Ion + ? JS::ProfilingCategoryPair::JS_IonMonkey + : JS::ProfilingCategoryPair::JS_Baseline); + writer.IntElement(CATEGORY, uint32_t(info.mCategory)); + writer.IntElement(SUBCATEGORY, info.mSubcategoryIndex); +} + +static nsCString JSONForJITFrame(JSContext* aContext, + const JS::ProfiledFrameHandle& aJITFrame, + UniqueJSONStrings& aUniqueStrings) { + nsCString json; + JSONStringRefWriteFunc jw(json); + SpliceableJSONWriter writer(jw, aUniqueStrings.SourceFailureLatch()); + StreamJITFrame(aContext, writer, aUniqueStrings, aJITFrame); + return json; +} + +void JITFrameInfo::AddInfoForRange( + uint64_t aRangeStart, uint64_t aRangeEnd, JSContext* aCx, + const std::function<void(const std::function<void(void*)>&)>& + aJITAddressProvider) { + if (mLocalFailureLatchSource.Failed()) { + return; + } + + if (aRangeStart == aRangeEnd) { + return; + } + + MOZ_RELEASE_ASSERT(aRangeStart < aRangeEnd); + + if (!mRanges.empty()) { + const JITFrameInfoForBufferRange& prevRange = mRanges.back(); + MOZ_RELEASE_ASSERT(prevRange.mRangeEnd <= aRangeStart, + "Ranges must be non-overlapping and added in-order."); + } + + using JITFrameKey = JITFrameInfoForBufferRange::JITFrameKey; + + JITFrameInfoForBufferRange::JITAddressToJITFramesMap jitAddressToJITFrameMap; + JITFrameInfoForBufferRange::JITFrameToFrameJSONMap jitFrameToFrameJSONMap; + + aJITAddressProvider([&](void* aJITAddress) { + // Make sure that we have cached data for aJITAddress. + auto addressEntry = jitAddressToJITFrameMap.lookupForAdd(aJITAddress); + if (!addressEntry) { + Vector<JITFrameKey> jitFrameKeys; + for (JS::ProfiledFrameHandle handle : + JS::GetProfiledFrames(aCx, aJITAddress)) { + uint32_t depth = jitFrameKeys.length(); + JITFrameKey jitFrameKey{handle.canonicalAddress(), depth}; + auto frameEntry = jitFrameToFrameJSONMap.lookupForAdd(jitFrameKey); + if (!frameEntry) { + if (!jitFrameToFrameJSONMap.add( + frameEntry, jitFrameKey, + JSONForJITFrame(aCx, handle, *mUniqueStrings))) { + mLocalFailureLatchSource.SetFailure( + "OOM in JITFrameInfo::AddInfoForRange adding jit->frame map"); + return; + } + } + if (!jitFrameKeys.append(jitFrameKey)) { + mLocalFailureLatchSource.SetFailure( + "OOM in JITFrameInfo::AddInfoForRange adding jit frame key"); + return; + } + } + if (!jitAddressToJITFrameMap.add(addressEntry, aJITAddress, + std::move(jitFrameKeys))) { + mLocalFailureLatchSource.SetFailure( + "OOM in JITFrameInfo::AddInfoForRange adding addr->jit map"); + return; + } + } + }); + + if (!mRanges.append(JITFrameInfoForBufferRange{ + aRangeStart, aRangeEnd, std::move(jitAddressToJITFrameMap), + std::move(jitFrameToFrameJSONMap)})) { + mLocalFailureLatchSource.SetFailure( + "OOM in JITFrameInfo::AddInfoForRange adding range"); + return; + } +} + +struct ProfileSample { + uint32_t mStack = 0; + double mTime = 0.0; + Maybe<double> mResponsiveness; + RunningTimes mRunningTimes; +}; + +// Write CPU measurements with "Delta" unit, which is some amount of work that +// happened since the previous sample. +static void WriteDelta(AutoArraySchemaWriter& aSchemaWriter, uint32_t aProperty, + uint64_t aDelta) { + aSchemaWriter.IntElement(aProperty, int64_t(aDelta)); +} + +static void WriteSample(SpliceableJSONWriter& aWriter, + const ProfileSample& aSample) { + enum Schema : uint32_t { + STACK = 0, + TIME = 1, + EVENT_DELAY = 2 +#define RUNNING_TIME_SCHEMA(index, name, unit, jsonProperty) , name + PROFILER_FOR_EACH_RUNNING_TIME(RUNNING_TIME_SCHEMA) +#undef RUNNING_TIME_SCHEMA + }; + + AutoArraySchemaWriter writer(aWriter); + + writer.IntElement(STACK, aSample.mStack); + + writer.TimeMsElement(TIME, aSample.mTime); + + if (aSample.mResponsiveness.isSome()) { + writer.DoubleElement(EVENT_DELAY, *aSample.mResponsiveness); + } + +#define RUNNING_TIME_STREAM(index, name, unit, jsonProperty) \ + aSample.mRunningTimes.GetJson##name##unit().apply( \ + [&writer](const uint64_t& aValue) { \ + Write##unit(writer, name, aValue); \ + }); + + PROFILER_FOR_EACH_RUNNING_TIME(RUNNING_TIME_STREAM) + +#undef RUNNING_TIME_STREAM +} + +static void StreamMarkerAfterKind( + ProfileBufferEntryReader& aER, + ProcessStreamingContext& aProcessStreamingContext) { + ThreadStreamingContext* threadData = nullptr; + mozilla::base_profiler_markers_detail::DeserializeAfterKindAndStream( + aER, + [&](ProfilerThreadId aThreadId) -> baseprofiler::SpliceableJSONWriter* { + threadData = + aProcessStreamingContext.GetThreadStreamingContext(aThreadId); + return threadData ? &threadData->mMarkersDataWriter : nullptr; + }, + [&](ProfileChunkedBuffer& aChunkedBuffer) { + ProfilerBacktrace backtrace("", &aChunkedBuffer); + MOZ_ASSERT(threadData, + "threadData should have been set before calling here"); + backtrace.StreamJSON(threadData->mMarkersDataWriter, + aProcessStreamingContext.ProcessStartTime(), + *threadData->mUniqueStacks); + }, + [&](mozilla::base_profiler_markers_detail::Streaming::DeserializerTag + aTag) { + MOZ_ASSERT(threadData, + "threadData should have been set before calling here"); + + size_t payloadSize = aER.RemainingBytes(); + + ProfileBufferEntryReader::DoubleSpanOfConstBytes spans = + aER.ReadSpans(payloadSize); + if (MOZ_LIKELY(spans.IsSingleSpan())) { + // Only a single span, we can just refer to it directly + // instead of copying it. + profiler::ffi::gecko_profiler_serialize_marker_for_tag( + aTag, spans.mFirstOrOnly.Elements(), payloadSize, + &threadData->mMarkersDataWriter); + } else { + // Two spans, we need to concatenate them by copying. + uint8_t* payloadBuffer = new uint8_t[payloadSize]; + spans.CopyBytesTo(payloadBuffer); + profiler::ffi::gecko_profiler_serialize_marker_for_tag( + aTag, payloadBuffer, payloadSize, + &threadData->mMarkersDataWriter); + delete[] payloadBuffer; + } + }); +} + +class EntryGetter { + public: + explicit EntryGetter( + ProfileChunkedBuffer::Reader& aReader, + mozilla::FailureLatch& aFailureLatch, + mozilla::ProgressLogger aProgressLogger = {}, + uint64_t aInitialReadPos = 0, + ProcessStreamingContext* aStreamingContextForMarkers = nullptr) + : mFailureLatch(aFailureLatch), + mStreamingContextForMarkers(aStreamingContextForMarkers), + mBlockIt( + aReader.At(ProfileBufferBlockIndex::CreateFromProfileBufferIndex( + aInitialReadPos))), + mBlockItEnd(aReader.end()), + mRangeStart(mBlockIt.BufferRangeStart().ConvertToProfileBufferIndex()), + mRangeSize( + double(mBlockIt.BufferRangeEnd().ConvertToProfileBufferIndex() - + mRangeStart)), + mProgressLogger(std::move(aProgressLogger)) { + SetLocalProgress(ProgressLogger::NO_LOCATION_UPDATE); + if (!ReadLegacyOrEnd()) { + // Find and read the next non-legacy entry. + Next(); + } + } + + bool Has() const { + return (!mFailureLatch.Failed()) && (mBlockIt != mBlockItEnd); + } + + const ProfileBufferEntry& Get() const { + MOZ_ASSERT(Has() || mFailureLatch.Failed(), + "Caller should have checked `Has()` before `Get()`"); + return mEntry; + } + + void Next() { + MOZ_ASSERT(Has() || mFailureLatch.Failed(), + "Caller should have checked `Has()` before `Next()`"); + ++mBlockIt; + ReadUntilLegacyOrEnd(); + } + + // Hand off the current iterator to the caller, which may be used to read + // any kind of entries (legacy or modern). + ProfileChunkedBuffer::BlockIterator Iterator() const { return mBlockIt; } + + // After `Iterator()` was used, we can restart from *after* its updated + // position. + void RestartAfter(const ProfileChunkedBuffer::BlockIterator& it) { + mBlockIt = it; + if (!Has()) { + return; + } + Next(); + } + + ProfileBufferBlockIndex CurBlockIndex() const { + return mBlockIt.CurrentBlockIndex(); + } + + uint64_t CurPos() const { + return CurBlockIndex().ConvertToProfileBufferIndex(); + } + + void SetLocalProgress(const char* aLocation) { + mProgressLogger.SetLocalProgress( + ProportionValue{double(CurBlockIndex().ConvertToProfileBufferIndex() - + mRangeStart) / + mRangeSize}, + aLocation); + } + + private: + // Try to read the entry at the current `mBlockIt` position. + // * If we're at the end of the buffer, just return `true`. + // * If there is a "legacy" entry (containing a real `ProfileBufferEntry`), + // read it into `mEntry`, and return `true` as well. + // * Otherwise the entry contains a "modern" type that cannot be read into + // `mEntry`, return `false` (so `EntryGetter` can skip to another entry). + bool ReadLegacyOrEnd() { + if (!Has()) { + return true; + } + // Read the entry "kind", which is always at the start of all entries. + ProfileBufferEntryReader er = *mBlockIt; + auto type = static_cast<ProfileBufferEntry::Kind>( + er.ReadObject<ProfileBufferEntry::KindUnderlyingType>()); + MOZ_ASSERT(static_cast<ProfileBufferEntry::KindUnderlyingType>(type) < + static_cast<ProfileBufferEntry::KindUnderlyingType>( + ProfileBufferEntry::Kind::MODERN_LIMIT)); + if (type >= ProfileBufferEntry::Kind::LEGACY_LIMIT) { + if (type == ProfileBufferEntry::Kind::Marker && + mStreamingContextForMarkers) { + StreamMarkerAfterKind(er, *mStreamingContextForMarkers); + if (!Has()) { + return true; + } + SetLocalProgress("Processed marker"); + } + er.SetRemainingBytes(0); + return false; + } + // Here, we have a legacy item, we need to read it from the start. + // Because the above `ReadObject` moved the reader, we ned to reset it to + // the start of the entry before reading the whole entry. + er = *mBlockIt; + er.ReadBytes(&mEntry, er.RemainingBytes()); + return true; + } + + void ReadUntilLegacyOrEnd() { + for (;;) { + if (ReadLegacyOrEnd()) { + // Either we're at the end, or we could read a legacy entry -> Done. + break; + } + // Otherwise loop around until we hit a legacy entry or the end. + ++mBlockIt; + } + SetLocalProgress(ProgressLogger::NO_LOCATION_UPDATE); + } + + mozilla::FailureLatch& mFailureLatch; + + ProcessStreamingContext* const mStreamingContextForMarkers; + + ProfileBufferEntry mEntry; + ProfileChunkedBuffer::BlockIterator mBlockIt; + const ProfileChunkedBuffer::BlockIterator mBlockItEnd; + + // Progress logger, and the data needed to compute the current relative + // position in the buffer. + const mozilla::ProfileBufferIndex mRangeStart; + const double mRangeSize; + mozilla::ProgressLogger mProgressLogger; +}; + +// The following grammar shows legal sequences of profile buffer entries. +// The sequences beginning with a ThreadId entry are known as "samples". +// +// ( +// ( /* Samples */ +// ThreadId +// TimeBeforeCompactStack +// RunningTimes? +// UnresponsivenessDurationMs? +// CompactStack +// /* internally including: +// ( NativeLeafAddr +// | Label FrameFlags? DynamicStringFragment* +// LineNumber? CategoryPair? +// | JitReturnAddr +// )+ +// */ +// ) +// | ( /* Reference to a previous identical sample */ +// ThreadId +// TimeBeforeSameSample +// RunningTimes? +// SameSample +// ) +// | Marker +// | ( /* Counters */ +// CounterId +// Time +// ( +// CounterKey +// Count +// Number? +// )* +// ) +// | CollectionStart +// | CollectionEnd +// | Pause +// | Resume +// | ( ProfilerOverheadTime /* Sampling start timestamp */ +// ProfilerOverheadDuration /* Lock acquisition */ +// ProfilerOverheadDuration /* Expired markers cleaning */ +// ProfilerOverheadDuration /* Counters */ +// ProfilerOverheadDuration /* Threads */ +// ) +// )* +// +// The most complicated part is the stack entry sequence that begins with +// Label. Here are some examples. +// +// - ProfilingStack frames without a dynamic string: +// +// Label("js::RunScript") +// CategoryPair(JS::ProfilingCategoryPair::JS) +// +// Label("XREMain::XRE_main") +// LineNumber(4660) +// CategoryPair(JS::ProfilingCategoryPair::OTHER) +// +// Label("ElementRestyler::ComputeStyleChangeFor") +// LineNumber(3003) +// CategoryPair(JS::ProfilingCategoryPair::CSS) +// +// - ProfilingStack frames with a dynamic string: +// +// Label("nsObserverService::NotifyObservers") +// FrameFlags(uint64_t(ProfilingStackFrame::Flags::IS_LABEL_FRAME)) +// DynamicStringFragment("domwindo") +// DynamicStringFragment("wopened") +// LineNumber(291) +// CategoryPair(JS::ProfilingCategoryPair::OTHER) +// +// Label("") +// FrameFlags(uint64_t(ProfilingStackFrame::Flags::IS_JS_FRAME)) +// DynamicStringFragment("closeWin") +// DynamicStringFragment("dow (chr") +// DynamicStringFragment("ome://gl") +// DynamicStringFragment("obal/con") +// DynamicStringFragment("tent/glo") +// DynamicStringFragment("balOverl") +// DynamicStringFragment("ay.js:5)") +// DynamicStringFragment("") # this string holds the closing '\0' +// LineNumber(25) +// CategoryPair(JS::ProfilingCategoryPair::JS) +// +// Label("") +// FrameFlags(uint64_t(ProfilingStackFrame::Flags::IS_JS_FRAME)) +// DynamicStringFragment("bound (s") +// DynamicStringFragment("elf-host") +// DynamicStringFragment("ed:914)") +// LineNumber(945) +// CategoryPair(JS::ProfilingCategoryPair::JS) +// +// - A profiling stack frame with an overly long dynamic string: +// +// Label("") +// FrameFlags(uint64_t(ProfilingStackFrame::Flags::IS_LABEL_FRAME)) +// DynamicStringFragment("(too lon") +// DynamicStringFragment("g)") +// LineNumber(100) +// CategoryPair(JS::ProfilingCategoryPair::NETWORK) +// +// - A wasm JIT frame: +// +// Label("") +// FrameFlags(uint64_t(0)) +// DynamicStringFragment("wasm-fun") +// DynamicStringFragment("ction[87") +// DynamicStringFragment("36] (blo") +// DynamicStringFragment("b:http:/") +// DynamicStringFragment("/webasse") +// DynamicStringFragment("mbly.org") +// DynamicStringFragment("/3dc5759") +// DynamicStringFragment("4-ce58-4") +// DynamicStringFragment("626-975b") +// DynamicStringFragment("-08ad116") +// DynamicStringFragment("30bc1:38") +// DynamicStringFragment("29856)") +// +// - A JS frame in a synchronous sample: +// +// Label("") +// FrameFlags(uint64_t(ProfilingStackFrame::Flags::IS_LABEL_FRAME)) +// DynamicStringFragment("u (https") +// DynamicStringFragment("://perf-") +// DynamicStringFragment("html.io/") +// DynamicStringFragment("ac0da204") +// DynamicStringFragment("aaa44d75") +// DynamicStringFragment("a800.bun") +// DynamicStringFragment("dle.js:2") +// DynamicStringFragment("5)") + +// Because this is a format entirely internal to the Profiler, any parsing +// error indicates a bug in the ProfileBuffer writing or the parser itself, +// or possibly flaky hardware. +#define ERROR_AND_CONTINUE(msg) \ + { \ + fprintf(stderr, "ProfileBuffer parse error: %s", msg); \ + MOZ_ASSERT(false, msg); \ + continue; \ + } + +struct StreamingParametersForThread { + SpliceableJSONWriter& mWriter; + UniqueStacks& mUniqueStacks; + ThreadStreamingContext::PreviousStackState& mPreviousStackState; + uint32_t& mPreviousStack; + + StreamingParametersForThread( + SpliceableJSONWriter& aWriter, UniqueStacks& aUniqueStacks, + ThreadStreamingContext::PreviousStackState& aPreviousStackState, + uint32_t& aPreviousStack) + : mWriter(aWriter), + mUniqueStacks(aUniqueStacks), + mPreviousStackState(aPreviousStackState), + mPreviousStack(aPreviousStack) {} +}; + +// GetStreamingParametersForThreadCallback: +// (ProfilerThreadId) -> Maybe<StreamingParametersForThread> +template <typename GetStreamingParametersForThreadCallback> +ProfilerThreadId ProfileBuffer::DoStreamSamplesAndMarkersToJSON( + mozilla::FailureLatch& aFailureLatch, + GetStreamingParametersForThreadCallback&& + aGetStreamingParametersForThreadCallback, + double aSinceTime, ProcessStreamingContext* aStreamingContextForMarkers, + mozilla::ProgressLogger aProgressLogger) const { + UniquePtr<char[]> dynStrBuf = MakeUnique<char[]>(kMaxFrameKeyLength); + + return mEntries.Read([&](ProfileChunkedBuffer::Reader* aReader) { + MOZ_ASSERT(aReader, + "ProfileChunkedBuffer cannot be out-of-session when sampler is " + "running"); + + ProfilerThreadId processedThreadId; + + EntryGetter e(*aReader, aFailureLatch, std::move(aProgressLogger), + /* aInitialReadPos */ 0, aStreamingContextForMarkers); + + for (;;) { + // This block skips entries until we find the start of the next sample. + // This is useful in three situations. + // + // - The circular buffer overwrites old entries, so when we start parsing + // we might be in the middle of a sample, and we must skip forward to + // the start of the next sample. + // + // - We skip samples that don't have an appropriate ThreadId or Time. + // + // - We skip range Pause, Resume, CollectionStart, Marker, Counter + // and CollectionEnd entries between samples. + while (e.Has()) { + if (e.Get().IsThreadId()) { + break; + } + e.Next(); + } + + if (!e.Has()) { + break; + } + + // Due to the skip_to_next_sample block above, if we have an entry here it + // must be a ThreadId entry. + MOZ_ASSERT(e.Get().IsThreadId()); + + ProfilerThreadId threadId = e.Get().GetThreadId(); + e.Next(); + + Maybe<StreamingParametersForThread> streamingParameters = + std::forward<GetStreamingParametersForThreadCallback>( + aGetStreamingParametersForThreadCallback)(threadId); + + // Ignore samples that are for the wrong thread. + if (!streamingParameters) { + continue; + } + + SpliceableJSONWriter& writer = streamingParameters->mWriter; + UniqueStacks& uniqueStacks = streamingParameters->mUniqueStacks; + ThreadStreamingContext::PreviousStackState& previousStackState = + streamingParameters->mPreviousStackState; + uint32_t& previousStack = streamingParameters->mPreviousStack; + + auto ReadStack = [&](EntryGetter& e, double time, uint64_t entryPosition, + const Maybe<double>& unresponsiveDuration, + const RunningTimes& runningTimes) { + if (writer.Failed()) { + return; + } + + Maybe<UniqueStacks::StackKey> maybeStack = + uniqueStacks.BeginStack(UniqueStacks::FrameKey("(root)")); + if (!maybeStack) { + writer.SetFailure("BeginStack failure"); + return; + } + + UniqueStacks::StackKey stack = *maybeStack; + + int numFrames = 0; + while (e.Has()) { + if (e.Get().IsNativeLeafAddr()) { + numFrames++; + + void* pc = e.Get().GetPtr(); + e.Next(); + + nsAutoCString functionNameOrAddress = + uniqueStacks.FunctionNameOrAddress(pc); + + maybeStack = uniqueStacks.AppendFrame( + stack, UniqueStacks::FrameKey(functionNameOrAddress.get())); + if (!maybeStack) { + writer.SetFailure("AppendFrame failure"); + return; + } + stack = *maybeStack; + + } else if (e.Get().IsLabel()) { + numFrames++; + + const char* label = e.Get().GetString(); + e.Next(); + + using FrameFlags = js::ProfilingStackFrame::Flags; + uint32_t frameFlags = 0; + if (e.Has() && e.Get().IsFrameFlags()) { + frameFlags = uint32_t(e.Get().GetUint64()); + e.Next(); + } + + bool relevantForJS = + frameFlags & uint32_t(FrameFlags::RELEVANT_FOR_JS); + + bool isBaselineInterp = + frameFlags & uint32_t(FrameFlags::IS_BLINTERP_FRAME); + + // Copy potential dynamic string fragments into dynStrBuf, so that + // dynStrBuf will then contain the entire dynamic string. + size_t i = 0; + dynStrBuf[0] = '\0'; + while (e.Has()) { + if (e.Get().IsDynamicStringFragment()) { + char chars[ProfileBufferEntry::kNumChars]; + e.Get().CopyCharsInto(chars); + for (char c : chars) { + if (i < kMaxFrameKeyLength) { + dynStrBuf[i] = c; + i++; + } + } + e.Next(); + } else { + break; + } + } + dynStrBuf[kMaxFrameKeyLength - 1] = '\0'; + bool hasDynamicString = (i != 0); + + nsAutoCStringN<1024> frameLabel; + if (label[0] != '\0' && hasDynamicString) { + if (frameFlags & uint32_t(FrameFlags::STRING_TEMPLATE_METHOD)) { + frameLabel.AppendPrintf("%s.%s", label, dynStrBuf.get()); + } else if (frameFlags & + uint32_t(FrameFlags::STRING_TEMPLATE_GETTER)) { + frameLabel.AppendPrintf("get %s.%s", label, dynStrBuf.get()); + } else if (frameFlags & + uint32_t(FrameFlags::STRING_TEMPLATE_SETTER)) { + frameLabel.AppendPrintf("set %s.%s", label, dynStrBuf.get()); + } else { + frameLabel.AppendPrintf("%s %s", label, dynStrBuf.get()); + } + } else if (hasDynamicString) { + frameLabel.Append(dynStrBuf.get()); + } else { + frameLabel.Append(label); + } + + uint64_t innerWindowID = 0; + if (e.Has() && e.Get().IsInnerWindowID()) { + innerWindowID = uint64_t(e.Get().GetUint64()); + e.Next(); + } + + Maybe<unsigned> line; + if (e.Has() && e.Get().IsLineNumber()) { + line = Some(unsigned(e.Get().GetInt())); + e.Next(); + } + + Maybe<unsigned> column; + if (e.Has() && e.Get().IsColumnNumber()) { + column = Some(unsigned(e.Get().GetInt())); + e.Next(); + } + + Maybe<JS::ProfilingCategoryPair> categoryPair; + if (e.Has() && e.Get().IsCategoryPair()) { + categoryPair = + Some(JS::ProfilingCategoryPair(uint32_t(e.Get().GetInt()))); + e.Next(); + } + + maybeStack = uniqueStacks.AppendFrame( + stack, + UniqueStacks::FrameKey(std::move(frameLabel), relevantForJS, + isBaselineInterp, innerWindowID, line, + column, categoryPair)); + if (!maybeStack) { + writer.SetFailure("AppendFrame failure"); + return; + } + stack = *maybeStack; + + } else if (e.Get().IsJitReturnAddr()) { + numFrames++; + + // A JIT frame may expand to multiple frames due to inlining. + void* pc = e.Get().GetPtr(); + const Maybe<Vector<UniqueStacks::FrameKey>>& frameKeys = + uniqueStacks.LookupFramesForJITAddressFromBufferPos( + pc, entryPosition ? entryPosition : e.CurPos()); + MOZ_RELEASE_ASSERT( + frameKeys, + "Attempting to stream samples for a buffer range " + "for which we don't have JITFrameInfo?"); + for (const UniqueStacks::FrameKey& frameKey : *frameKeys) { + maybeStack = uniqueStacks.AppendFrame(stack, frameKey); + if (!maybeStack) { + writer.SetFailure("AppendFrame failure"); + return; + } + stack = *maybeStack; + } + + e.Next(); + + } else { + break; + } + } + + // Even if this stack is considered empty, it contains the root frame, + // which needs to be in the JSON output because following "same samples" + // may refer to it when reusing this sample.mStack. + const Maybe<uint32_t> stackIndex = + uniqueStacks.GetOrAddStackIndex(stack); + if (!stackIndex) { + writer.SetFailure("Can't add unique string for stack"); + return; + } + + // And store that possibly-empty stack in case it's followed by "same + // sample" entries. + previousStack = *stackIndex; + previousStackState = (numFrames == 0) + ? ThreadStreamingContext::eStackWasEmpty + : ThreadStreamingContext::eStackWasNotEmpty; + + // Even if too old or empty, we did process a sample for this thread id. + processedThreadId = threadId; + + // Discard samples that are too old. + if (time < aSinceTime) { + return; + } + + if (numFrames == 0 && runningTimes.IsEmpty()) { + // It is possible to have empty stacks if native stackwalking is + // disabled. Skip samples with empty stacks, unless we have useful + // running times. + return; + } + + WriteSample(writer, ProfileSample{*stackIndex, time, + unresponsiveDuration, runningTimes}); + }; // End of `ReadStack(EntryGetter&)` lambda. + + if (e.Has() && e.Get().IsTime()) { + double time = e.Get().GetDouble(); + e.Next(); + // Note: Even if this sample is too old (before aSinceTime), we still + // need to read it, so that its frames are in the tables, in case there + // is a same-sample following it that would be after aSinceTime, which + // would need these frames to be present. + + ReadStack(e, time, 0, Nothing{}, RunningTimes{}); + + e.SetLocalProgress("Processed sample"); + } else if (e.Has() && e.Get().IsTimeBeforeCompactStack()) { + double time = e.Get().GetDouble(); + // Note: Even if this sample is too old (before aSinceTime), we still + // need to read it, so that its frames are in the tables, in case there + // is a same-sample following it that would be after aSinceTime, which + // would need these frames to be present. + + RunningTimes runningTimes; + Maybe<double> unresponsiveDuration; + + ProfileChunkedBuffer::BlockIterator it = e.Iterator(); + for (;;) { + ++it; + if (it.IsAtEnd()) { + break; + } + ProfileBufferEntryReader er = *it; + ProfileBufferEntry::Kind kind = + er.ReadObject<ProfileBufferEntry::Kind>(); + + // There may be running times before the CompactStack. + if (kind == ProfileBufferEntry::Kind::RunningTimes) { + er.ReadIntoObject(runningTimes); + continue; + } + + // There may be an UnresponsiveDurationMs before the CompactStack. + if (kind == ProfileBufferEntry::Kind::UnresponsiveDurationMs) { + unresponsiveDuration = Some(er.ReadObject<double>()); + continue; + } + + if (kind == ProfileBufferEntry::Kind::CompactStack) { + ProfileChunkedBuffer tempBuffer( + ProfileChunkedBuffer::ThreadSafety::WithoutMutex, + WorkerChunkManager()); + er.ReadIntoObject(tempBuffer); + tempBuffer.Read([&](ProfileChunkedBuffer::Reader* aReader) { + MOZ_ASSERT(aReader, + "Local ProfileChunkedBuffer cannot be out-of-session"); + // This is a compact stack, it should only contain one sample. + EntryGetter stackEntryGetter(*aReader, aFailureLatch); + ReadStack(stackEntryGetter, time, + it.CurrentBlockIndex().ConvertToProfileBufferIndex(), + unresponsiveDuration, runningTimes); + }); + WorkerChunkManager().Reset(tempBuffer.GetAllChunks()); + break; + } + + if (kind == ProfileBufferEntry::Kind::Marker && + aStreamingContextForMarkers) { + StreamMarkerAfterKind(er, *aStreamingContextForMarkers); + continue; + } + + MOZ_ASSERT(kind >= ProfileBufferEntry::Kind::LEGACY_LIMIT, + "There should be no legacy entries between " + "TimeBeforeCompactStack and CompactStack"); + er.SetRemainingBytes(0); + } + + e.RestartAfter(it); + + e.SetLocalProgress("Processed compact sample"); + } else if (e.Has() && e.Get().IsTimeBeforeSameSample()) { + if (previousStackState == ThreadStreamingContext::eNoStackYet) { + // We don't have any full sample yet, we cannot duplicate a "previous" + // one. This should only happen at most once per thread, for the very + // first sample. + continue; + } + + ProfileSample sample; + + // Keep the same `mStack` as previously output. + // Note that it may be empty, this is checked below before writing it. + sample.mStack = previousStack; + + sample.mTime = e.Get().GetDouble(); + + // Ignore samples that are too old. + if (sample.mTime < aSinceTime) { + e.Next(); + continue; + } + + sample.mResponsiveness = Nothing{}; + + sample.mRunningTimes.Clear(); + + ProfileChunkedBuffer::BlockIterator it = e.Iterator(); + for (;;) { + ++it; + if (it.IsAtEnd()) { + break; + } + ProfileBufferEntryReader er = *it; + ProfileBufferEntry::Kind kind = + er.ReadObject<ProfileBufferEntry::Kind>(); + + // There may be running times before the SameSample. + if (kind == ProfileBufferEntry::Kind::RunningTimes) { + er.ReadIntoObject(sample.mRunningTimes); + continue; + } + + if (kind == ProfileBufferEntry::Kind::SameSample) { + if (previousStackState == ThreadStreamingContext::eStackWasEmpty && + sample.mRunningTimes.IsEmpty()) { + // Skip samples with empty stacks, unless we have useful running + // times. + break; + } + WriteSample(writer, sample); + break; + } + + if (kind == ProfileBufferEntry::Kind::Marker && + aStreamingContextForMarkers) { + StreamMarkerAfterKind(er, *aStreamingContextForMarkers); + continue; + } + + MOZ_ASSERT(kind >= ProfileBufferEntry::Kind::LEGACY_LIMIT, + "There should be no legacy entries between " + "TimeBeforeSameSample and SameSample"); + er.SetRemainingBytes(0); + } + + e.RestartAfter(it); + + e.SetLocalProgress("Processed repeated sample"); + } else { + ERROR_AND_CONTINUE("expected a Time entry"); + } + } + + return processedThreadId; + }); +} + +ProfilerThreadId ProfileBuffer::StreamSamplesToJSON( + SpliceableJSONWriter& aWriter, ProfilerThreadId aThreadId, + double aSinceTime, UniqueStacks& aUniqueStacks, + mozilla::ProgressLogger aProgressLogger) const { + ThreadStreamingContext::PreviousStackState previousStackState = + ThreadStreamingContext::eNoStackYet; + uint32_t stack = 0u; +#ifdef DEBUG + int processedCount = 0; +#endif // DEBUG + return DoStreamSamplesAndMarkersToJSON( + aWriter.SourceFailureLatch(), + [&](ProfilerThreadId aReadThreadId) { + Maybe<StreamingParametersForThread> streamingParameters; +#ifdef DEBUG + ++processedCount; + MOZ_ASSERT( + aThreadId.IsSpecified() || + (processedCount == 1 && aReadThreadId.IsSpecified()), + "Unspecified aThreadId should only be used with 1-sample buffer"); +#endif // DEBUG + if (!aThreadId.IsSpecified() || aThreadId == aReadThreadId) { + streamingParameters.emplace(aWriter, aUniqueStacks, + previousStackState, stack); + } + return streamingParameters; + }, + aSinceTime, /* aStreamingContextForMarkers */ nullptr, + std::move(aProgressLogger)); +} + +void ProfileBuffer::StreamSamplesAndMarkersToJSON( + ProcessStreamingContext& aProcessStreamingContext, + mozilla::ProgressLogger aProgressLogger) const { + (void)DoStreamSamplesAndMarkersToJSON( + aProcessStreamingContext.SourceFailureLatch(), + [&](ProfilerThreadId aReadThreadId) { + Maybe<StreamingParametersForThread> streamingParameters; + ThreadStreamingContext* threadData = + aProcessStreamingContext.GetThreadStreamingContext(aReadThreadId); + if (threadData) { + streamingParameters.emplace( + threadData->mSamplesDataWriter, *threadData->mUniqueStacks, + threadData->mPreviousStackState, threadData->mPreviousStack); + } + return streamingParameters; + }, + aProcessStreamingContext.GetSinceTime(), &aProcessStreamingContext, + std::move(aProgressLogger)); +} + +void ProfileBuffer::AddJITInfoForRange( + uint64_t aRangeStart, ProfilerThreadId aThreadId, JSContext* aContext, + JITFrameInfo& aJITFrameInfo, + mozilla::ProgressLogger aProgressLogger) const { + // We can only process JitReturnAddr entries if we have a JSContext. + MOZ_RELEASE_ASSERT(aContext); + + aRangeStart = std::max(aRangeStart, BufferRangeStart()); + aJITFrameInfo.AddInfoForRange( + aRangeStart, BufferRangeEnd(), aContext, + [&](const std::function<void(void*)>& aJITAddressConsumer) { + // Find all JitReturnAddr entries in the given range for the given + // thread, and call aJITAddressConsumer with those addresses. + + mEntries.Read([&](ProfileChunkedBuffer::Reader* aReader) { + MOZ_ASSERT(aReader, + "ProfileChunkedBuffer cannot be out-of-session when " + "sampler is running"); + + EntryGetter e(*aReader, aJITFrameInfo.LocalFailureLatchSource(), + std::move(aProgressLogger), aRangeStart); + + while (true) { + // Advance to the next ThreadId entry. + while (e.Has() && !e.Get().IsThreadId()) { + e.Next(); + } + if (!e.Has()) { + break; + } + + MOZ_ASSERT(e.Get().IsThreadId()); + ProfilerThreadId threadId = e.Get().GetThreadId(); + e.Next(); + + // Ignore samples that are for a different thread. + if (threadId != aThreadId) { + continue; + } + + if (e.Has() && e.Get().IsTime()) { + // Legacy stack. + e.Next(); + while (e.Has() && !e.Get().IsThreadId()) { + if (e.Get().IsJitReturnAddr()) { + aJITAddressConsumer(e.Get().GetPtr()); + } + e.Next(); + } + } else if (e.Has() && e.Get().IsTimeBeforeCompactStack()) { + // Compact stack. + ProfileChunkedBuffer::BlockIterator it = e.Iterator(); + for (;;) { + ++it; + if (it.IsAtEnd()) { + break; + } + ProfileBufferEntryReader er = *it; + ProfileBufferEntry::Kind kind = + er.ReadObject<ProfileBufferEntry::Kind>(); + if (kind == ProfileBufferEntry::Kind::CompactStack) { + ProfileChunkedBuffer tempBuffer( + ProfileChunkedBuffer::ThreadSafety::WithoutMutex, + WorkerChunkManager()); + er.ReadIntoObject(tempBuffer); + tempBuffer.Read([&](ProfileChunkedBuffer::Reader* aReader) { + MOZ_ASSERT( + aReader, + "Local ProfileChunkedBuffer cannot be out-of-session"); + EntryGetter stackEntryGetter( + *aReader, aJITFrameInfo.LocalFailureLatchSource()); + while (stackEntryGetter.Has()) { + if (stackEntryGetter.Get().IsJitReturnAddr()) { + aJITAddressConsumer(stackEntryGetter.Get().GetPtr()); + } + stackEntryGetter.Next(); + } + }); + WorkerChunkManager().Reset(tempBuffer.GetAllChunks()); + break; + } + + MOZ_ASSERT(kind >= ProfileBufferEntry::Kind::LEGACY_LIMIT, + "There should be no legacy entries between " + "TimeBeforeCompactStack and CompactStack"); + er.SetRemainingBytes(0); + } + + e.Next(); + } else if (e.Has() && e.Get().IsTimeBeforeSameSample()) { + // Sample index, nothing to do. + + } else { + ERROR_AND_CONTINUE("expected a Time entry"); + } + } + }); + }); +} + +void ProfileBuffer::StreamMarkersToJSON( + SpliceableJSONWriter& aWriter, ProfilerThreadId aThreadId, + const TimeStamp& aProcessStartTime, double aSinceTime, + UniqueStacks& aUniqueStacks, + mozilla::ProgressLogger aProgressLogger) const { + mEntries.ReadEach([&](ProfileBufferEntryReader& aER) { + auto type = static_cast<ProfileBufferEntry::Kind>( + aER.ReadObject<ProfileBufferEntry::KindUnderlyingType>()); + MOZ_ASSERT(static_cast<ProfileBufferEntry::KindUnderlyingType>(type) < + static_cast<ProfileBufferEntry::KindUnderlyingType>( + ProfileBufferEntry::Kind::MODERN_LIMIT)); + if (type == ProfileBufferEntry::Kind::Marker) { + mozilla::base_profiler_markers_detail::DeserializeAfterKindAndStream( + aER, + [&](const ProfilerThreadId& aMarkerThreadId) { + return (!aThreadId.IsSpecified() || aMarkerThreadId == aThreadId) + ? &aWriter + : nullptr; + }, + [&](ProfileChunkedBuffer& aChunkedBuffer) { + ProfilerBacktrace backtrace("", &aChunkedBuffer); + backtrace.StreamJSON(aWriter, aProcessStartTime, aUniqueStacks); + }, + [&](mozilla::base_profiler_markers_detail::Streaming::DeserializerTag + aTag) { + size_t payloadSize = aER.RemainingBytes(); + + ProfileBufferEntryReader::DoubleSpanOfConstBytes spans = + aER.ReadSpans(payloadSize); + if (MOZ_LIKELY(spans.IsSingleSpan())) { + // Only a single span, we can just refer to it directly + // instead of copying it. + profiler::ffi::gecko_profiler_serialize_marker_for_tag( + aTag, spans.mFirstOrOnly.Elements(), payloadSize, &aWriter); + } else { + // Two spans, we need to concatenate them by copying. + uint8_t* payloadBuffer = new uint8_t[payloadSize]; + spans.CopyBytesTo(payloadBuffer); + profiler::ffi::gecko_profiler_serialize_marker_for_tag( + aTag, payloadBuffer, payloadSize, &aWriter); + delete[] payloadBuffer; + } + }); + } else { + // The entry was not a marker, we need to skip to the end. + aER.SetRemainingBytes(0); + } + }); +} + +void ProfileBuffer::StreamProfilerOverheadToJSON( + SpliceableJSONWriter& aWriter, const TimeStamp& aProcessStartTime, + double aSinceTime, mozilla::ProgressLogger aProgressLogger) const { + mEntries.Read([&](ProfileChunkedBuffer::Reader* aReader) { + MOZ_ASSERT(aReader, + "ProfileChunkedBuffer cannot be out-of-session when sampler is " + "running"); + + EntryGetter e(*aReader, aWriter.SourceFailureLatch(), + std::move(aProgressLogger)); + + enum Schema : uint32_t { + TIME = 0, + LOCKING = 1, + MARKER_CLEANING = 2, + COUNTERS = 3, + THREADS = 4 + }; + + aWriter.StartObjectProperty("profilerOverhead"); + aWriter.StartObjectProperty("samples"); + // Stream all sampling overhead data. We skip other entries, because we + // process them in StreamSamplesToJSON()/etc. + { + JSONSchemaWriter schema(aWriter); + schema.WriteField("time"); + schema.WriteField("locking"); + schema.WriteField("expiredMarkerCleaning"); + schema.WriteField("counters"); + schema.WriteField("threads"); + } + + aWriter.StartArrayProperty("data"); + double firstTime = 0.0; + double lastTime = 0.0; + ProfilerStats intervals, overheads, lockings, cleanings, counters, threads; + while (e.Has()) { + // valid sequence: ProfilerOverheadTime, ProfilerOverheadDuration * 4 + if (e.Get().IsProfilerOverheadTime()) { + double time = e.Get().GetDouble(); + if (time >= aSinceTime) { + e.Next(); + if (!e.Has() || !e.Get().IsProfilerOverheadDuration()) { + ERROR_AND_CONTINUE( + "expected a ProfilerOverheadDuration entry after " + "ProfilerOverheadTime"); + } + double locking = e.Get().GetDouble(); + e.Next(); + if (!e.Has() || !e.Get().IsProfilerOverheadDuration()) { + ERROR_AND_CONTINUE( + "expected a ProfilerOverheadDuration entry after " + "ProfilerOverheadTime,ProfilerOverheadDuration"); + } + double cleaning = e.Get().GetDouble(); + e.Next(); + if (!e.Has() || !e.Get().IsProfilerOverheadDuration()) { + ERROR_AND_CONTINUE( + "expected a ProfilerOverheadDuration entry after " + "ProfilerOverheadTime,ProfilerOverheadDuration*2"); + } + double counter = e.Get().GetDouble(); + e.Next(); + if (!e.Has() || !e.Get().IsProfilerOverheadDuration()) { + ERROR_AND_CONTINUE( + "expected a ProfilerOverheadDuration entry after " + "ProfilerOverheadTime,ProfilerOverheadDuration*3"); + } + double thread = e.Get().GetDouble(); + + if (firstTime == 0.0) { + firstTime = time; + } else { + // Note that we'll have 1 fewer interval than other numbers (because + // we need both ends of an interval to know its duration). The final + // difference should be insignificant over the expected many + // thousands of iterations. + intervals.Count(time - lastTime); + } + lastTime = time; + overheads.Count(locking + cleaning + counter + thread); + lockings.Count(locking); + cleanings.Count(cleaning); + counters.Count(counter); + threads.Count(thread); + + AutoArraySchemaWriter writer(aWriter); + writer.TimeMsElement(TIME, time); + writer.DoubleElement(LOCKING, locking); + writer.DoubleElement(MARKER_CLEANING, cleaning); + writer.DoubleElement(COUNTERS, counter); + writer.DoubleElement(THREADS, thread); + } + } + e.Next(); + } + aWriter.EndArray(); // data + aWriter.EndObject(); // samples + + // Only output statistics if there is at least one full interval (and + // therefore at least two samplings.) + if (intervals.n > 0) { + aWriter.StartObjectProperty("statistics"); + aWriter.DoubleProperty("profiledDuration", lastTime - firstTime); + aWriter.IntProperty("samplingCount", overheads.n); + aWriter.DoubleProperty("overheadDurations", overheads.sum); + aWriter.DoubleProperty("overheadPercentage", + overheads.sum / (lastTime - firstTime)); +#define PROFILER_STATS(name, var) \ + aWriter.DoubleProperty("mean" name, (var).sum / (var).n); \ + aWriter.DoubleProperty("min" name, (var).min); \ + aWriter.DoubleProperty("max" name, (var).max); + PROFILER_STATS("Interval", intervals); + PROFILER_STATS("Overhead", overheads); + PROFILER_STATS("Lockings", lockings); + PROFILER_STATS("Cleaning", cleanings); + PROFILER_STATS("Counter", counters); + PROFILER_STATS("Thread", threads); +#undef PROFILER_STATS + aWriter.EndObject(); // statistics + } + aWriter.EndObject(); // profilerOverhead + }); +} + +struct CounterKeyedSample { + double mTime; + uint64_t mNumber; + int64_t mCount; +}; + +using CounterKeyedSamples = Vector<CounterKeyedSample>; + +static LazyLogModule sFuzzyfoxLog("Fuzzyfox"); + +using CounterMap = HashMap<uint64_t, CounterKeyedSamples>; + +// HashMap lookup, if not found, a default value is inserted. +// Returns reference to (existing or new) value inside the HashMap. +template <typename HashM, typename Key> +static auto& LookupOrAdd(HashM& aMap, Key&& aKey) { + auto addPtr = aMap.lookupForAdd(aKey); + if (!addPtr) { + MOZ_RELEASE_ASSERT(aMap.add(addPtr, std::forward<Key>(aKey), + typename HashM::Entry::ValueType{})); + MOZ_ASSERT(!!addPtr); + } + return addPtr->value(); +} + +void ProfileBuffer::StreamCountersToJSON( + SpliceableJSONWriter& aWriter, const TimeStamp& aProcessStartTime, + double aSinceTime, mozilla::ProgressLogger aProgressLogger) const { + // Because this is a format entirely internal to the Profiler, any parsing + // error indicates a bug in the ProfileBuffer writing or the parser itself, + // or possibly flaky hardware. + + mEntries.Read([&](ProfileChunkedBuffer::Reader* aReader) { + MOZ_ASSERT(aReader, + "ProfileChunkedBuffer cannot be out-of-session when sampler is " + "running"); + + EntryGetter e(*aReader, aWriter.SourceFailureLatch(), + std::move(aProgressLogger)); + + enum Schema : uint32_t { TIME = 0, COUNT = 1, NUMBER = 2 }; + + // Stream all counters. We skip other entries, because we process them in + // StreamSamplesToJSON()/etc. + // + // Valid sequence in the buffer: + // CounterID + // Time + // ( CounterKey Count Number? )* + // + // And the JSON (example): + // "counters": { + // "name": "malloc", + // "category": "Memory", + // "description": "Amount of allocated memory", + // "sample_groups": { + // "id": 0, + // "samples": { + // "schema": {"time": 0, "number": 1, "count": 2}, + // "data": [ + // [ + // 16117.033968000002, + // 2446216, + // 6801320 + // ], + // [ + // 16118.037638, + // 2446216, + // 6801320 + // ], + // ], + // } + // } + // }, + + // Build the map of counters and populate it + HashMap<void*, CounterMap> counters; + + while (e.Has()) { + // skip all non-Counters, including if we start in the middle of a counter + if (e.Get().IsCounterId()) { + void* id = e.Get().GetPtr(); + CounterMap& counter = LookupOrAdd(counters, id); + e.Next(); + if (!e.Has() || !e.Get().IsTime()) { + ERROR_AND_CONTINUE("expected a Time entry"); + } + double time = e.Get().GetDouble(); + e.Next(); + if (time >= aSinceTime) { + while (e.Has() && e.Get().IsCounterKey()) { + uint64_t key = e.Get().GetUint64(); + CounterKeyedSamples& data = LookupOrAdd(counter, key); + e.Next(); + if (!e.Has() || !e.Get().IsCount()) { + ERROR_AND_CONTINUE("expected a Count entry"); + } + int64_t count = e.Get().GetUint64(); + e.Next(); + uint64_t number; + if (!e.Has() || !e.Get().IsNumber()) { + number = 0; + } else { + number = e.Get().GetInt64(); + e.Next(); + } + CounterKeyedSample sample = {time, number, count}; + MOZ_RELEASE_ASSERT(data.append(sample)); + } + } else { + // skip counter sample - only need to skip the initial counter + // id, then let the loop at the top skip the rest + } + } else { + e.Next(); + } + } + // we have a map of a map of counter entries; dump them to JSON + if (counters.count() == 0) { + return; + } + + aWriter.StartArrayProperty("counters"); + for (auto iter = counters.iter(); !iter.done(); iter.next()) { + CounterMap& counter = iter.get().value(); + const BaseProfilerCount* base_counter = + static_cast<const BaseProfilerCount*>(iter.get().key()); + + aWriter.Start(); + aWriter.StringProperty("name", MakeStringSpan(base_counter->mLabel)); + aWriter.StringProperty("category", + MakeStringSpan(base_counter->mCategory)); + aWriter.StringProperty("description", + MakeStringSpan(base_counter->mDescription)); + + aWriter.StartArrayProperty("sample_groups"); + for (auto counter_iter = counter.iter(); !counter_iter.done(); + counter_iter.next()) { + CounterKeyedSamples& samples = counter_iter.get().value(); + uint64_t key = counter_iter.get().key(); + + size_t size = samples.length(); + if (size == 0) { + continue; + } + + bool hasNumber = false; + for (size_t i = 0; i < size; i++) { + if (samples[i].mNumber != 0) { + hasNumber = true; + break; + } + } + + aWriter.StartObjectElement(); + { + aWriter.IntProperty("id", static_cast<int64_t>(key)); + aWriter.StartObjectProperty("samples"); + { + JSONSchemaWriter schema(aWriter); + schema.WriteField("time"); + schema.WriteField("count"); + if (hasNumber) { + schema.WriteField("number"); + } + } + + aWriter.StartArrayProperty("data"); + double previousSkippedTime = 0.0; + uint64_t previousNumber = 0; + int64_t previousCount = 0; + for (size_t i = 0; i < size; i++) { + // Encode as deltas, and only encode if different than the previous + // or next sample; Always write the first and last samples. + if (i == 0 || i == size - 1 || + samples[i].mNumber != previousNumber || + samples[i].mCount != previousCount || + // Ensure we ouput the first 0 before skipping samples. + (i >= 2 && (samples[i - 2].mNumber != previousNumber || + samples[i - 2].mCount != previousCount))) { + if (i != 0 && samples[i].mTime >= samples[i - 1].mTime) { + MOZ_LOG(sFuzzyfoxLog, mozilla::LogLevel::Error, + ("Fuzzyfox Profiler Assertion: %f >= %f", + samples[i].mTime, samples[i - 1].mTime)); + } + MOZ_ASSERT(i == 0 || samples[i].mTime >= samples[i - 1].mTime); + MOZ_ASSERT(samples[i].mNumber >= previousNumber); + MOZ_ASSERT(samples[i].mNumber - previousNumber <= + uint64_t(std::numeric_limits<int64_t>::max())); + + int64_t numberDelta = + static_cast<int64_t>(samples[i].mNumber - previousNumber); + int64_t countDelta = samples[i].mCount - previousCount; + + if (previousSkippedTime != 0.0 && + (numberDelta != 0 || countDelta != 0)) { + // Write the last skipped sample, unless the new one is all + // zeroes (that'd be redundant) This is useful to know when a + // certain value was last sampled, so that the front-end graph + // will be more correct. + AutoArraySchemaWriter writer(aWriter); + writer.TimeMsElement(TIME, previousSkippedTime); + // The deltas are effectively zeroes, since no change happened + // between the last actually-written sample and the last skipped + // one. + writer.IntElement(COUNT, 0); + if (hasNumber) { + writer.IntElement(NUMBER, 0); + } + } + + AutoArraySchemaWriter writer(aWriter); + writer.TimeMsElement(TIME, samples[i].mTime); + writer.IntElement(COUNT, countDelta); + if (hasNumber) { + writer.IntElement(NUMBER, numberDelta); + } + + previousSkippedTime = 0.0; + previousNumber = samples[i].mNumber; + previousCount = samples[i].mCount; + } else { + previousSkippedTime = samples[i].mTime; + } + } + aWriter.EndArray(); // data + aWriter.EndObject(); // samples + } + aWriter.EndObject(); // sample_groups item + } + aWriter.EndArray(); // sample groups + aWriter.End(); // for each counter + } + aWriter.EndArray(); // counters + }); +} + +#undef ERROR_AND_CONTINUE + +static void AddPausedRange(SpliceableJSONWriter& aWriter, const char* aReason, + const Maybe<double>& aStartTime, + const Maybe<double>& aEndTime) { + aWriter.Start(); + if (aStartTime) { + aWriter.TimeDoubleMsProperty("startTime", *aStartTime); + } else { + aWriter.NullProperty("startTime"); + } + if (aEndTime) { + aWriter.TimeDoubleMsProperty("endTime", *aEndTime); + } else { + aWriter.NullProperty("endTime"); + } + aWriter.StringProperty("reason", MakeStringSpan(aReason)); + aWriter.End(); +} + +void ProfileBuffer::StreamPausedRangesToJSON( + SpliceableJSONWriter& aWriter, double aSinceTime, + mozilla::ProgressLogger aProgressLogger) const { + mEntries.Read([&](ProfileChunkedBuffer::Reader* aReader) { + MOZ_ASSERT(aReader, + "ProfileChunkedBuffer cannot be out-of-session when sampler is " + "running"); + + EntryGetter e(*aReader, aWriter.SourceFailureLatch(), + aProgressLogger.CreateSubLoggerFromTo( + 1_pc, "Streaming pauses...", 99_pc, "Streamed pauses")); + + Maybe<double> currentPauseStartTime; + Maybe<double> currentCollectionStartTime; + + while (e.Has()) { + if (e.Get().IsPause()) { + currentPauseStartTime = Some(e.Get().GetDouble()); + } else if (e.Get().IsResume()) { + AddPausedRange(aWriter, "profiler-paused", currentPauseStartTime, + Some(e.Get().GetDouble())); + currentPauseStartTime = Nothing(); + } else if (e.Get().IsCollectionStart()) { + currentCollectionStartTime = Some(e.Get().GetDouble()); + } else if (e.Get().IsCollectionEnd()) { + AddPausedRange(aWriter, "collecting", currentCollectionStartTime, + Some(e.Get().GetDouble())); + currentCollectionStartTime = Nothing(); + } + e.Next(); + } + + if (currentPauseStartTime) { + AddPausedRange(aWriter, "profiler-paused", currentPauseStartTime, + Nothing()); + } + if (currentCollectionStartTime) { + AddPausedRange(aWriter, "collecting", currentCollectionStartTime, + Nothing()); + } + }); +} + +bool ProfileBuffer::DuplicateLastSample(ProfilerThreadId aThreadId, + double aSampleTimeMs, + Maybe<uint64_t>& aLastSample, + const RunningTimes& aRunningTimes) { + if (!aLastSample) { + return false; + } + + if (mEntries.IsIndexInCurrentChunk(ProfileBufferIndex{*aLastSample})) { + // The last (fully-written) sample is in this chunk, we can refer to it. + + // Note that between now and when we write the SameSample below, another + // chunk could have been started, so the SameSample will in fact refer to a + // block in a previous chunk. This is okay, because: + // - When serializing to JSON, if that chunk is still there, we'll still be + // able to find that old stack, so nothing will be lost. + // - If unfortunately that chunk has been destroyed, we will lose this + // sample. But this will only happen to the first sample (per thread) in + // in the whole JSON output, because the next time we're here to duplicate + // the same sample again, IsIndexInCurrentChunk will say `false` and we + // will fall back to the normal copy or even re-sample. Losing the first + // sample out of many in a whole recording is acceptable. + // + // |---| = chunk, S = Sample, D = Duplicate, s = same sample + // |---S-s-s--| |s-D--s--s-| |s-D--s---s| + // Later, the first chunk is destroyed/recycled: + // |s-D--s--s-| |s-D--s---s| |-... + // Output: ^ ^ ^ ^ + // `-|--|-------|--- Same but no previous -> lost. + // `--|-------|--- Full duplicate sample. + // `-------|--- Same with previous -> okay. + // `--- Same but now we have a previous -> okay! + + AUTO_PROFILER_STATS(DuplicateLastSample_SameSample); + + // Add the thread id first. We don't update `aLastSample` because we are not + // writing a full sample. + (void)AddThreadIdEntry(aThreadId); + + // Copy the new time, to be followed by a SameSample. + AddEntry(ProfileBufferEntry::TimeBeforeSameSample(aSampleTimeMs)); + + // Add running times if they have data. + if (!aRunningTimes.IsEmpty()) { + mEntries.PutObjects(ProfileBufferEntry::Kind::RunningTimes, + aRunningTimes); + } + + // Finish with a SameSample entry. + mEntries.PutObjects(ProfileBufferEntry::Kind::SameSample); + + return true; + } + + AUTO_PROFILER_STATS(DuplicateLastSample_copy); + + ProfileChunkedBuffer tempBuffer( + ProfileChunkedBuffer::ThreadSafety::WithoutMutex, WorkerChunkManager()); + + auto retrieveWorkerChunk = MakeScopeExit( + [&]() { WorkerChunkManager().Reset(tempBuffer.GetAllChunks()); }); + + const bool ok = mEntries.Read([&](ProfileChunkedBuffer::Reader* aReader) { + MOZ_ASSERT(aReader, + "ProfileChunkedBuffer cannot be out-of-session when sampler is " + "running"); + + // DuplicateLastSample is only called during profiling, so we don't need a + // progress logger (only useful when capturing the final profile). + EntryGetter e(*aReader, mozilla::FailureLatchInfallibleSource::Singleton(), + ProgressLogger{}, *aLastSample); + + if (e.CurPos() != *aLastSample) { + // The last sample is no longer within the buffer range, so we cannot + // use it. Reset the stored buffer position to Nothing(). + aLastSample.reset(); + return false; + } + + MOZ_RELEASE_ASSERT(e.Has() && e.Get().IsThreadId() && + e.Get().GetThreadId() == aThreadId); + + e.Next(); + + // Go through the whole entry and duplicate it, until we find the next + // one. + while (e.Has()) { + switch (e.Get().GetKind()) { + case ProfileBufferEntry::Kind::Pause: + case ProfileBufferEntry::Kind::Resume: + case ProfileBufferEntry::Kind::PauseSampling: + case ProfileBufferEntry::Kind::ResumeSampling: + case ProfileBufferEntry::Kind::CollectionStart: + case ProfileBufferEntry::Kind::CollectionEnd: + case ProfileBufferEntry::Kind::ThreadId: + case ProfileBufferEntry::Kind::TimeBeforeSameSample: + // We're done. + return true; + case ProfileBufferEntry::Kind::Time: + // Copy with new time + AddEntry(tempBuffer, ProfileBufferEntry::Time(aSampleTimeMs)); + break; + case ProfileBufferEntry::Kind::TimeBeforeCompactStack: { + // Copy with new time, followed by a compact stack. + AddEntry(tempBuffer, + ProfileBufferEntry::TimeBeforeCompactStack(aSampleTimeMs)); + + // Add running times if they have data. + if (!aRunningTimes.IsEmpty()) { + tempBuffer.PutObjects(ProfileBufferEntry::Kind::RunningTimes, + aRunningTimes); + } + + // The `CompactStack` *must* be present afterwards, but may not + // immediately follow `TimeBeforeCompactStack` (e.g., some markers + // could be written in-between), so we need to look for it in the + // following entries. + ProfileChunkedBuffer::BlockIterator it = e.Iterator(); + for (;;) { + ++it; + if (it.IsAtEnd()) { + break; + } + ProfileBufferEntryReader er = *it; + auto kind = static_cast<ProfileBufferEntry::Kind>( + er.ReadObject<ProfileBufferEntry::KindUnderlyingType>()); + MOZ_ASSERT( + static_cast<ProfileBufferEntry::KindUnderlyingType>(kind) < + static_cast<ProfileBufferEntry::KindUnderlyingType>( + ProfileBufferEntry::Kind::MODERN_LIMIT)); + if (kind == ProfileBufferEntry::Kind::CompactStack) { + // Found our CompactStack, just make a copy of the whole entry. + er = *it; + auto bytes = er.RemainingBytes(); + MOZ_ASSERT(bytes < + ProfileBufferChunkManager::scExpectedMaximumStackSize); + tempBuffer.Put(bytes, [&](Maybe<ProfileBufferEntryWriter>& aEW) { + MOZ_ASSERT(aEW.isSome(), "tempBuffer cannot be out-of-session"); + aEW->WriteFromReader(er, bytes); + }); + // CompactStack marks the end, we're done. + break; + } + + MOZ_ASSERT(kind >= ProfileBufferEntry::Kind::LEGACY_LIMIT, + "There should be no legacy entries between " + "TimeBeforeCompactStack and CompactStack"); + er.SetRemainingBytes(0); + // Here, we have encountered a non-legacy entry that was not the + // CompactStack we're looking for; just continue the search... + } + // We're done. + return true; + } + case ProfileBufferEntry::Kind::CounterKey: + case ProfileBufferEntry::Kind::Number: + case ProfileBufferEntry::Kind::Count: + // Don't copy anything not part of a thread's stack sample + break; + case ProfileBufferEntry::Kind::CounterId: + // CounterId is normally followed by Time - if so, we'd like + // to skip it. If we duplicate Time, it won't hurt anything, just + // waste buffer space (and this can happen if the CounterId has + // fallen off the end of the buffer, but Time (and Number/Count) + // are still in the buffer). + e.Next(); + if (e.Has() && e.Get().GetKind() != ProfileBufferEntry::Kind::Time) { + // this would only happen if there was an invalid sequence + // in the buffer. Don't skip it. + continue; + } + // we've skipped Time + break; + case ProfileBufferEntry::Kind::ProfilerOverheadTime: + // ProfilerOverheadTime is normally followed by + // ProfilerOverheadDuration*4 - if so, we'd like to skip it. Don't + // duplicate, as we are in the middle of a sampling and will soon + // capture its own overhead. + e.Next(); + // A missing Time would only happen if there was an invalid + // sequence in the buffer. Don't skip unexpected entry. + if (e.Has() && + e.Get().GetKind() != + ProfileBufferEntry::Kind::ProfilerOverheadDuration) { + continue; + } + e.Next(); + if (e.Has() && + e.Get().GetKind() != + ProfileBufferEntry::Kind::ProfilerOverheadDuration) { + continue; + } + e.Next(); + if (e.Has() && + e.Get().GetKind() != + ProfileBufferEntry::Kind::ProfilerOverheadDuration) { + continue; + } + e.Next(); + if (e.Has() && + e.Get().GetKind() != + ProfileBufferEntry::Kind::ProfilerOverheadDuration) { + continue; + } + // we've skipped ProfilerOverheadTime and + // ProfilerOverheadDuration*4. + break; + default: { + // Copy anything else we don't know about. + AddEntry(tempBuffer, e.Get()); + break; + } + } + e.Next(); + } + return true; + }); + + if (!ok) { + return false; + } + + // If the buffer was big enough, there won't be any cleared blocks. + if (tempBuffer.GetState().mClearedBlockCount != 0) { + // No need to try to read stack again as it won't fit. Reset the stored + // buffer position to Nothing(). + aLastSample.reset(); + return false; + } + + aLastSample = Some(AddThreadIdEntry(aThreadId)); + + mEntries.AppendContents(tempBuffer); + + return true; +} + +void ProfileBuffer::DiscardSamplesBeforeTime(double aTime) { + // This function does nothing! + // The duration limit will be removed from Firefox, see bug 1632365. + Unused << aTime; +} + +// END ProfileBuffer +//////////////////////////////////////////////////////////////////////// |