Bug 1414759 - Replace some unnecessary media prefs with code constants. r=cpearce

Specifically:
- media.decoder.limit
- media.num-decode-threads
- media.resampling.rate
- media.wmf.decoder.thread-count
- media.cache.resource-index

--HG--
extra : rebase_source : a46aa7078b98b4731ec96b66398c51aa6cb42d27

dom/ipc/ContentPrefs.cpp

@@ -136,7 +136,6 @@ const char* mozilla::dom::ContentPrefs::gInitPrefs[] = {
   "media.cubeb_latency_msg_frames",
   "media.cubeb_latency_playback_ms",
   "media.decoder-doctor.wmf-disabled-is-failure",
-  "media.decoder.limit",
   "media.decoder.recycle.enabled",
   "media.dormant-on-pause-timeout-ms",
   "media.eme.audio.blank",
@@ -151,11 +150,9 @@ const char* mozilla::dom::ContentPrefs::gInitPrefs[] = {
   "media.gmp.insecure.allow",
   "media.gpu-process-decoder",
   "media.libavcodec.allow-obsolete",
-  "media.num-decode-threads",
   "media.ogg.enabled",
   "media.ogg.flac.enabled",
   "media.resampling.enabled",
-  "media.resampling.rate",
   "media.ruin-av-sync.enabled",
   "media.rust.test_mode",
   "media.suspend-bkgnd-video.delay-ms",
@@ -170,7 +167,6 @@ const char* mozilla::dom::ContentPrefs::gInitPrefs[] = {
   "media.webspeech.test.fake_fsm_events",
   "media.webspeech.test.fake_recognition_service",
   "media.wmf.allow-unsupported-resolutions",
-  "media.wmf.decoder.thread-count",
   "media.wmf.enabled",
   "media.wmf.skip-blacklist",
   "media.wmf.vp9.enabled",

dom/media/MediaFormatReader.cpp

@@ -197,9 +197,23 @@ private:
   GlobalAllocPolicy& mPolicy; // reference to a singleton object.
 };
 
+static int32_t
+MediaDecoderLimitDefault()
+{
+#ifdef MOZ_WIDGET_ANDROID
+  if (jni::GetAPIVersion() < 18) {
+    // Older Android versions have broken support for multiple simultaneous
+    // decoders, see bug 1278574.
+    return 1;
+  }
+#endif
+  // Otherwise, set no decoder limit.
+  return -1;
+}
+
 GlobalAllocPolicy::GlobalAllocPolicy()
   : mMonitor("DecoderAllocPolicy::mMonitor")
-  , mDecoderLimit(MediaPrefs::MediaDecoderLimit())
+  , mDecoderLimit(MediaDecoderLimitDefault())
 {
   SystemGroup::Dispatch(
     TaskCategory::Other,

dom/media/MediaPrefs.h

@@ -92,7 +92,6 @@ private:
   DECL_MEDIA_PREF("media.memory_caches_combined_limit_kb",    MediaMemoryCachesCombinedLimitKb, uint32_t, 524288);
   DECL_MEDIA_PREF("media.memory_caches_combined_limit_pc_sysmem",
                                                               MediaMemoryCachesCombinedLimitPcSysmem, uint32_t, 5);
-  DECL_MEDIA_PREF("media.cache.resource-index",               MediaResourceIndexCache, uint32_t, 8192);
 
   DECL_MEDIA_PREF("media.cache_resume_threshold",             MediaCacheResumeThreshold, int32_t, 10);
   DECL_MEDIA_PREF("media.cache_readahead_limit",              MediaCacheReadaheadLimit, int32_t, 30);
@@ -100,7 +99,6 @@ private:
   // AudioSink
   DECL_MEDIA_PREF("accessibility.monoaudio.enable",           MonoAudio, bool, false);
   DECL_MEDIA_PREF("media.resampling.enabled",                 AudioSinkResampling, bool, false);
-  DECL_MEDIA_PREF("media.resampling.rate",                    AudioSinkResampleRate, uint32_t, 48000);
 #if defined(XP_WIN) || defined(XP_DARWIN) || defined(MOZ_PULSEAUDIO)
   // libcubeb backend implement .get_preferred_channel_layout
   DECL_MEDIA_PREF("media.forcestereo.enabled",                AudioSinkForceStereo, bool, false);
@@ -140,7 +138,6 @@ private:
   DECL_MEDIA_PREF("media.wmf.skip-blacklist",                 PDMWMFSkipBlacklist, bool, false);
   DECL_MEDIA_PREF("media.decoder-doctor.wmf-disabled-is-failure", DecoderDoctorWMFDisabledIsFailure, bool, false);
   DECL_MEDIA_PREF("media.wmf.vp9.enabled",                    PDMWMFVP9DecoderEnabled, bool, true);
-  DECL_MEDIA_PREF("media.wmf.decoder.thread-count",           PDMWMFThreadCount, int32_t, -1);
 #endif
   DECL_MEDIA_PREF("media.decoder.recycle.enabled",            MediaDecoderCheckRecycling, bool, false);
   DECL_MEDIA_PREF("media.decoder.skip-to-next-key-frame.enabled", MFRSkipToNextKeyFrameEnabled, bool, true);
@@ -165,9 +162,6 @@ private:
   DECL_MEDIA_PREF("media.webspeech.recognition.enable",       WebSpeechRecognitionEnabled, bool, false);
   DECL_MEDIA_PREF("media.webspeech.recognition.force_enable", WebSpeechRecognitionForceEnabled, bool, false);
 
-  DECL_MEDIA_PREF("media.num-decode-threads",                 MediaThreadPoolDefaultCount, uint32_t, 4);
-  DECL_MEDIA_PREF("media.decoder.limit",                      MediaDecoderLimit, int32_t, MediaDecoderLimitDefault());
-
 #if defined(RELEASE_OR_BETA)
   DECL_MEDIA_PREF("media.audio-max-decode-error",             MaxAudioDecodeError, uint32_t, 3);
   DECL_MEDIA_PREF("media.video-max-decode-error",             MaxVideoDecodeError, uint32_t, 2);
@@ -216,20 +210,6 @@ private:
   template<class T> friend class StaticAutoPtr;
   static StaticAutoPtr<MediaPrefs> sInstance;
 
-  // Default value functions
-  static int32_t MediaDecoderLimitDefault()
-  {
-#ifdef MOZ_WIDGET_ANDROID
-    if (jni::GetAPIVersion() < 18) {
-      // Older Android versions have broken support for multiple simultaneous
-      // decoders, see bug 1278574.
-      return 1;
-    }
-#endif
-    // Otherwise, set no decoder limit.
-    return -1;
-  }
-
   // Creating these to avoid having to include Preferences.h in the .h
   static void PrefAddVarCache(bool*, const char*, bool);
   static void PrefAddVarCache(int32_t*, const char*, int32_t);

dom/media/MediaResource.cpp

@@ -5,9 +5,10 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "MediaResource.h"
-#include "mozilla/DebugOnly.h"
 #include "MediaPrefs.h"
+#include "mozilla/DebugOnly.h"
 #include "mozilla/Logging.h"
+#include "mozilla/MathAlgorithms.h"
 #include "mozilla/SystemGroup.h"
 #include "mozilla/ErrorNames.h"
 
@@ -42,11 +43,15 @@ MediaResource::Destroy()
 NS_IMPL_ADDREF(MediaResource)
 NS_IMPL_RELEASE_WITH_DESTROY(MediaResource, Destroy())
 
+static const uint32_t kMediaResourceIndexCacheSize = 8192;
+static_assert(IsPowerOfTwo(kMediaResourceIndexCacheSize),
+              "kMediaResourceIndexCacheSize cache size must be a power of 2");
+
 MediaResourceIndex::MediaResourceIndex(MediaResource* aResource)
   : mResource(aResource)
   , mOffset(0)
   , mCacheBlockSize(aResource->ShouldCacheReads()
-                      ? SelectCacheSize(MediaPrefs::MediaResourceIndexCache())
+                      ? kMediaResourceIndexCacheSize
                       : 0)
   , mCachedOffset(0)
   , mCachedBytes(0)
@@ -513,32 +518,6 @@ MediaResourceIndex::GetLength() const
   return mResource->GetLength();
 }
 
-// Select the next power of 2 (in range 32B-128KB, or 0 -> no cache)
-/* static */
-uint32_t
-MediaResourceIndex::SelectCacheSize(uint32_t aHint)
-{
-  if (aHint == 0) {
-    return 0;
-  }
-  if (aHint <= 32) {
-    return 32;
-  }
-  if (aHint > 64 * 1024) {
-    return 128 * 1024;
-  }
-  // 32-bit next power of 2, from:
-  // http://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2
-  aHint--;
-  aHint |= aHint >> 1;
-  aHint |= aHint >> 2;
-  aHint |= aHint >> 4;
-  aHint |= aHint >> 8;
-  aHint |= aHint >> 16;
-  aHint++;
-  return aHint;
-}
-
 uint32_t
 MediaResourceIndex::IndexInCache(int64_t aOffsetInFile) const
 {

dom/media/MediaResource.h

@@ -265,9 +265,6 @@ private:
                          uint32_t aCount,
                          uint32_t* aBytes);
 
-  // Select the next power of 2 (in range 32B-128KB, or 0 -> no cache)
-  static uint32_t SelectCacheSize(uint32_t aHint);
-
   // Maps a file offset to a mCachedBlock index.
   uint32_t IndexInCache(int64_t aOffsetInFile) const;
 

dom/media/VideoUtils.cpp

@@ -209,8 +209,10 @@ already_AddRefed<SharedThreadPool> GetMediaThreadPool(MediaThreadType aType)
       name = "MediaPlayback";
       break;
   }
+
+  static const uint32_t kMediaThreadPoolDefaultCount = 4;
   return SharedThreadPool::
-    Get(nsDependentCString(name), MediaPrefs::MediaThreadPoolDefaultCount());
+    Get(nsDependentCString(name), kMediaThreadPoolDefaultCount);
 }
 
 bool

dom/media/mediasink/AudioSink.cpp

@@ -51,7 +51,7 @@ AudioSink::AudioSink(AbstractThread* aThread,
   bool resampling = MediaPrefs::AudioSinkResampling();
 
   if (resampling) {
-    mOutputRate = MediaPrefs::AudioSinkResampleRate();
+    mOutputRate = 48000;
   } else if (mInfo.mRate == 44100 || mInfo.mRate == 48000) {
     // The original rate is of good quality and we want to minimize unecessary
     // resampling. The common scenario being that the sampling rate is one or

dom/media/platforms/wmf/WMFDecoderModule.cpp

@@ -74,15 +74,9 @@ WMFDecoderModule::GetNumDecoderThreads()
   int32_t numCores = PR_GetNumberOfProcessors();
 
   // If we have more than 4 cores, let the decoder decide how many threads.
-  // On an 8 core machine, WMF chooses 4 decoder threads
-  const int WMF_DECODER_DEFAULT = -1;
-  int32_t prefThreadCount = WMF_DECODER_DEFAULT;
-  if (XRE_GetProcessType() != GeckoProcessType_GPU) {
-    prefThreadCount = MediaPrefs::PDMWMFThreadCount();
-  }
-  if (prefThreadCount != WMF_DECODER_DEFAULT) {
-    return std::max(prefThreadCount, 1);
-  } else if (numCores > 4) {
+  // On an 8 core machine, WMF chooses 4 decoder threads.
+  static const int WMF_DECODER_DEFAULT = -1;
+  if (numCores > 4) {
     return WMF_DECODER_DEFAULT;
   }
   return std::max(numCores - 1, 1);

modules/libpref/init/all.js

@@ -333,10 +333,6 @@ pref("media.memory_cache_max_size", 8192);
 pref("media.memory_caches_combined_limit_kb", 524288);
 pref("media.memory_caches_combined_limit_pc_sysmem", 5);
 
-// Cache size hint (in bytes) for each MediaResourceIndex.
-// 0 -> no cache. Will use next power of 2, clamped to 32B-128KB.
-pref("media.cache.resource-index", 8192);
-
 // We'll throttle the download if the download rate is throttle-factor times
 // the estimated playback rate, AND we satisfy the cache readahead_limit
 // above. The estimated playback rate is time_duration/length_in_bytes.
@@ -368,7 +364,6 @@ pref("media.mp4.enabled", true);
 pref("media.use-blank-decoder", false);
 #ifdef MOZ_WMF
 pref("media.wmf.enabled", true);
-pref("media.wmf.decoder.thread-count", -1);
 pref("media.wmf.dxva.enabled", true);
 pref("media.wmf.dxva.d3d11.enabled", true);
 pref("media.wmf.dxva.max-videos", 8);