dom/media/Tracing.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
   5  * You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "Tracing.h"
   8
   9 #include <inttypes.h>
  10
  11 using namespace mozilla;
  12
  13 using TracingPhase = mozilla::AsyncLogger::TracingPhase;
  14
  15 mozilla::AsyncLogger gAudioCallbackTraceLogger;
  16 static std::atomic<int> gTracingStarted(0);
  17
  18 void StartAudioCallbackTracing() {
  19 #ifdef MOZ_REAL_TIME_TRACING
  20   int cnt = gTracingStarted.fetch_add(1, std::memory_order_seq_cst);
  21   if (cnt == 0) {
  22     // This is a noop if the logger has not been enabled.
  23     gAudioCallbackTraceLogger.Start();
  24   }
  25 #endif
  26 }
  27
  28 void StopAudioCallbackTracing() {
  29 #ifdef MOZ_REAL_TIME_TRACING
  30   int cnt = gTracingStarted.fetch_sub(1, std::memory_order_seq_cst);
  31   if (cnt == 1) {
  32     // This is a noop if the logger has not been enabled.
  33     gAudioCallbackTraceLogger.Stop();
  34   }
  35 #endif
  36 }
  37
  38 void AutoTracer::PrintEvent(const char* aName, const char* aCategory,
  39                             const char* aComment, TracingPhase aPhase) {
  40 #ifdef MOZ_REAL_TIME_TRACING
  41   mLogger.Log(aName, aCategory, aComment, aPhase);
  42 #endif
  43 }
  44
  45 void AutoTracer::PrintBudget(const char* aName, const char* aCategory,
  46                              uint64_t aDuration, uint64_t aFrames,
  47                              uint64_t aSampleRate) {
  48 #ifdef MOZ_REAL_TIME_TRACING
  49   mLogger.LogDuration(aName, aCategory, aDuration, aFrames, aSampleRate);
  50 #endif
  51 }
  52
  53 AutoTracer::AutoTracer(AsyncLogger& aLogger, const char* aLocation,
  54                        EventType aEventType, uint64_t aFrames,
  55                        uint64_t aSampleRate)
  56     : mLogger(aLogger),
  57       mLocation(aLocation),
  58       mComment(nullptr),
  59       mEventType(aEventType) {
  60   MOZ_ASSERT(aEventType == EventType::BUDGET);
  61
  62   if (aLogger.Enabled()) {
  63     float durationUS = (static_cast<float>(aFrames) / aSampleRate) * 1e6;
  64     PrintBudget(aLocation, "perf", durationUS, aFrames, aSampleRate);
  65   }
  66 }
  67
  68 AutoTracer::AutoTracer(AsyncLogger& aLogger, const char* aLocation,
  69                        EventType aEventType, const char* aComment)
  70     : mLogger(aLogger),
  71       mLocation(aLocation),
  72       mComment(aComment),
  73       mEventType(aEventType) {
  74   MOZ_ASSERT(aEventType == EventType::DURATION);
  75   if (aLogger.Enabled()) {
  76     PrintEvent(aLocation, "perf", mComment, AsyncLogger::TracingPhase::BEGIN);
  77   }
  78 }
  79
  80 AutoTracer::~AutoTracer() {
  81   if (mEventType == EventType::DURATION) {
  82     if (mLogger.Enabled()) {
  83       PrintEvent(mLocation, "perf", mComment, AsyncLogger::TracingPhase::END);
  84     }
  85   }
  86 }