Quelle ProfileBuffer.cpp Sprache: C

/* -*- 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/ColumnNumber.h"  // JS::LimitedColumnNumberOneOrigin
#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(
    JS::ProfilingCategoryPair aCategory, const char* aLabel) {
  mBuf.CollectCodeLocation("", aLabel, 0, 0, Nothing(), Nothing(),
                           Some(aCategory));
}

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()) {
          JS::LimitedColumnNumberOneOrigin col;
          line = Some(JS_PCToLineNumber(aFrame.script(), aFrame.pc(), &col));
          column = Some(col.oneOriginValue());
        }
      }

    } 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()));
}

quality95%

¤ Dauer der Verarbeitung: 0.17 Sekunden (vorverarbeitet) ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.

Bemerkung:

Die farbliche Syntaxdarstellung ist noch experimentell.