mozilla-central/tools/profiler/core/ProfileBufferEntry.cpp (file symbol)

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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/. */
#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 CounterSample {
double mTime;
uint64_t mNumber;
int64_t mCount;
};
using CounterSamples = Vector<CounterSample>;
static LazyLogModule sFuzzyfoxLog("Fuzzyfox");
// 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
// ( Count Number? )*
//
// And the JSON (example):
// "counters": {
// "name": "malloc",
// "category": "Memory",
// "description": "Amount of allocated memory",
// "samples": {
// "schema": {"time": 0, "count": 1, "number": 2},
// "data": [
// [
// 16117.033968000002,
// 2446216,
// 6801320
// ],
// [
// 16118.037638,
// 2446216,
// 6801320
// ],
// ],
// },
// }
// Build the map of counters and populate it
HashMap<void*, CounterSamples> 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();
CounterSamples& data = 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) {
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();
}
CounterSample 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 counter entries; dump them to JSON
if (counters.count() == 0) {
return;
}
aWriter.StartArrayProperty("counters");
for (auto iter = counters.iter(); !iter.done(); iter.next()) {
CounterSamples& samples = iter.get().value();
size_t size = samples.length();
if (size == 0) {
continue;
}
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));
bool hasNumber = false;
for (size_t i = 0; i < size; i++) {
if (samples[i].mNumber != 0) {
hasNumber = true;
break;
}
}
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.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::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
////////////////////////////////////////////////////////////////////////