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/* -*- Mode: C++; tab-width: 2; 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 "ProfileBuffer.h"
#include "BaseProfiler.h"
#include "js/GCAPI.h"
#include "jsfriendapi.h"
#include "mozilla/MathAlgorithms.h"
#include "nsJSPrincipals.h"
#include "nsScriptSecurityManager.h"
using namespace mozilla;
ProfileBuffer::ProfileBuffer(ProfileChunkedBuffer& aBuffer)
: mEntries(aBuffer) {
// Assume the given buffer is in-session.
MOZ_ASSERT(mEntries.IsInSession());
}
/* static */
ProfileBufferBlockIndex ProfileBuffer::AddEntry(
ProfileChunkedBuffer& aProfileChunkedBuffer,
const ProfileBufferEntry& aEntry) {
switch (aEntry.GetKind()) {
#define SWITCH_KIND(KIND, TYPE, SIZE) \
case ProfileBufferEntry::Kind::KIND: { \
return aProfileChunkedBuffer.PutFrom(&aEntry, 1 + (SIZE)); \
}
FOR_EACH_PROFILE_BUFFER_ENTRY_KIND(SWITCH_KIND)
#undef SWITCH_KIND
default:
MOZ_ASSERT(false, "Unhandled ProfilerBuffer entry KIND");
return ProfileBufferBlockIndex{};
}
}
// Called from signal, call only reentrant functions
uint64_t ProfileBuffer::AddEntry(const ProfileBufferEntry& aEntry) {
return AddEntry(mEntries, aEntry).ConvertToProfileBufferIndex();
}
/* static */
ProfileBufferBlockIndex ProfileBuffer::AddThreadIdEntry(
ProfileChunkedBuffer& aProfileChunkedBuffer, ProfilerThreadId aThreadId) {
return AddEntry(aProfileChunkedBuffer,
ProfileBufferEntry::ThreadId(aThreadId));
}
uint64_t ProfileBuffer::AddThreadIdEntry(ProfilerThreadId aThreadId) {
return AddThreadIdEntry(mEntries, aThreadId).ConvertToProfileBufferIndex();
}
void ProfileBuffer::CollectCodeLocation(
const char* aLabel, const char* aStr, uint32_t aFrameFlags,
uint64_t aInnerWindowID, const Maybe<uint32_t>& aLineNumber,
const Maybe<uint32_t>& aColumnNumber,
const Maybe<JS::ProfilingCategoryPair>& aCategoryPair) {
AddEntry(ProfileBufferEntry::Label(aLabel));
AddEntry(ProfileBufferEntry::FrameFlags(uint64_t(aFrameFlags)));
if (aStr) {
// Store the string using one or more DynamicStringFragment entries.
size_t strLen = strlen(aStr) + 1; // +1 for the null terminator
// If larger than the prescribed limit, we will cut the string and end it
// with an ellipsis.
const bool tooBig = strLen > kMaxFrameKeyLength;
if (tooBig) {
strLen = kMaxFrameKeyLength;
}
char chars[ProfileBufferEntry::kNumChars];
for (size_t j = 0;; j += ProfileBufferEntry::kNumChars) {
// Store up to kNumChars characters in the entry.
size_t len = ProfileBufferEntry::kNumChars;
const bool last = j + len >= strLen;
if (last) {
// Only the last entry may be smaller than kNumChars.
len = strLen - j;
if (tooBig) {
// That last entry is part of a too-big string, replace the end
// characters with an ellipsis "...".
len = std::max(len, size_t(4));
chars[len - 4] = '.';
chars[len - 3] = '.';
chars[len - 2] = '.';
chars[len - 1] = '\0';
// Make sure the memcpy will not overwrite our ellipsis!
len -= 4;
}
}
memcpy(chars, &aStr[j], len);
AddEntry(ProfileBufferEntry::DynamicStringFragment(chars));
if (last) {
break;
}
}
}
if (aInnerWindowID) {
AddEntry(ProfileBufferEntry::InnerWindowID(aInnerWindowID));
}
if (aLineNumber) {
AddEntry(ProfileBufferEntry::LineNumber(*aLineNumber));
}
if (aColumnNumber) {
AddEntry(ProfileBufferEntry::ColumnNumber(*aColumnNumber));
}
if (aCategoryPair.isSome()) {
AddEntry(ProfileBufferEntry::CategoryPair(int(*aCategoryPair)));
}
}
size_t ProfileBuffer::SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const {
// Measurement of the following members may be added later if DMD finds it
// is worthwhile:
// - memory pointed to by the elements within mEntries
return mEntries.SizeOfExcludingThis(aMallocSizeOf);
}
size_t ProfileBuffer::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const {
return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
}
void ProfileBuffer::CollectOverheadStats(double aSamplingTimeMs,
TimeDuration aLocking,
TimeDuration aCleaning,
TimeDuration aCounters,
TimeDuration aThreads) {
double timeUs = aSamplingTimeMs * 1000.0;
if (mFirstSamplingTimeUs == 0.0) {
mFirstSamplingTimeUs = timeUs;
} 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.
mIntervalsUs.Count(timeUs - mLastSamplingTimeUs);
}
mLastSamplingTimeUs = timeUs;
double locking = aLocking.ToMilliseconds() * 1000.0;
double cleaning = aCleaning.ToMilliseconds() * 1000.0;
double counters = aCounters.ToMilliseconds() * 1000.0;
double threads = aThreads.ToMilliseconds() * 1000.0;
mOverheadsUs.Count(locking + cleaning + counters + threads);
mLockingsUs.Count(locking);
mCleaningsUs.Count(cleaning);
mCountersUs.Count(counters);
mThreadsUs.Count(threads);
static const bool sRecordSamplingOverhead = []() {
const char* recordOverheads = getenv("MOZ_PROFILER_RECORD_OVERHEADS");
return recordOverheads && recordOverheads[0] != '\0';
}();
if (sRecordSamplingOverhead) {
AddEntry(ProfileBufferEntry::ProfilerOverheadTime(aSamplingTimeMs));
AddEntry(ProfileBufferEntry::ProfilerOverheadDuration(locking));
AddEntry(ProfileBufferEntry::ProfilerOverheadDuration(cleaning));
AddEntry(ProfileBufferEntry::ProfilerOverheadDuration(counters));
AddEntry(ProfileBufferEntry::ProfilerOverheadDuration(threads));
}
}
ProfilerBufferInfo ProfileBuffer::GetProfilerBufferInfo() const {
return {BufferRangeStart(),
BufferRangeEnd(),
static_cast<uint32_t>(*mEntries.BufferLength() /
8), // 8 bytes per entry.
mIntervalsUs,
mOverheadsUs,
mLockingsUs,
mCleaningsUs,
mCountersUs,
mThreadsUs};
}
/* ProfileBufferCollector */
void ProfileBufferCollector::CollectNativeLeafAddr(void* aAddr) {
mBuf.AddEntry(ProfileBufferEntry::NativeLeafAddr(aAddr));
}
void ProfileBufferCollector::CollectJitReturnAddr(void* aAddr) {
mBuf.AddEntry(ProfileBufferEntry::JitReturnAddr(aAddr));
}
void ProfileBufferCollector::CollectWasmFrame(const char* aLabel) {
mBuf.CollectCodeLocation("", aLabel, 0, 0, Nothing(), Nothing(),
Some(JS::ProfilingCategoryPair::JS_Wasm));
}
void ProfileBufferCollector::CollectProfilingStackFrame(
const js::ProfilingStackFrame& aFrame) {
// WARNING: this function runs within the profiler's "critical section".
MOZ_ASSERT(aFrame.isLabelFrame() ||
(aFrame.isJsFrame() && !aFrame.isOSRFrame()));
const char* label = aFrame.label();
const char* dynamicString = aFrame.dynamicString();
Maybe<uint32_t> line;
Maybe<uint32_t> column;
if (aFrame.isJsFrame()) {
// There are two kinds of JS frames that get pushed onto the ProfilingStack.
//
// - label = "", dynamic string = <something>
// - label = "js::RunScript", dynamic string = nullptr
//
// The line number is only interesting in the first case.
if (label[0] == '\0') {
MOZ_ASSERT(dynamicString);
// We call aFrame.script() repeatedly -- rather than storing the result in
// a local variable in order -- to avoid rooting hazards.
if (aFrame.script()) {
if (aFrame.pc()) {
unsigned col = 0;
line = Some(JS_PCToLineNumber(aFrame.script(), aFrame.pc(), &col));
column = Some(col);
}
}
} else {
MOZ_ASSERT(strcmp(label, "js::RunScript") == 0 && !dynamicString);
}
} else {
MOZ_ASSERT(aFrame.isLabelFrame());
}
mBuf.CollectCodeLocation(label, dynamicString, aFrame.flags(),
aFrame.realmID(), line, column,
Some(aFrame.categoryPair()));
}