Bug 1831052 - Record audio codec process when FinishDecodeFirstFrame() runs r=padenot

Differential Revision: https://phabricator.services.mozilla.com/D176994

dom/media/MediaFormatReader.cpp

@@ -477,20 +477,8 @@ void MediaFormatReader::DecoderFactory::DoInitDecoder(Data& aData) {
                   ownerData.GetCurrentInfo()->mMimeType);
             }
             if (aTrack == TrackInfo::kAudioTrack) {
-              nsCString processName = ownerData.mDecoder->GetProcessName();
-              nsCString audioProcessPerCodecName(
-                  processName + ","_ns + ownerData.mDecoder->GetCodecName());
-              if (processName != "utility"_ns) {
-                if (!StaticPrefs::media_rdd_process_enabled()) {
-                  audioProcessPerCodecName += ",rdd-disabled"_ns;
-                }
-                if (!StaticPrefs::media_utility_process_enabled()) {
-                  audioProcessPerCodecName += ",utility-disabled"_ns;
-                }
-              }
-              Telemetry::ScalarAdd(
-                  Telemetry::ScalarID::MEDIA_AUDIO_PROCESS_PER_CODEC_NAME,
-                  NS_ConvertUTF8toUTF16(audioProcessPerCodecName), 1);
+              ownerData.mProcessName = ownerData.mDecoder->GetProcessName();
+              ownerData.mCodecName = ownerData.mDecoder->GetCodecName();
             }
           },
           [this, &aData, &ownerData](const MediaResult& aError) {
@@ -1373,6 +1361,12 @@ void MediaFormatReader::ReadUpdatedMetadata(MediaInfo* aInfo) {
     MutexAutoLock lock(mAudio.mMutex);
     if (HasAudio()) {
       aInfo->mAudio = *mAudio.GetWorkingInfo()->GetAsAudioInfo();
+      Maybe<nsCString> audioProcessPerCodecName = GetAudioProcessPerCodec();
+      if (audioProcessPerCodecName.isSome()) {
+        Telemetry::ScalarAdd(
+            Telemetry::ScalarID::MEDIA_AUDIO_PROCESS_PER_CODEC_NAME,
+            NS_ConvertUTF8toUTF16(*audioProcessPerCodecName), 1);
+      }
     }
   }
 }
@@ -3248,6 +3242,28 @@ RefPtr<GenericPromise> MediaFormatReader::RequestDebugInfo(
   return GenericPromise::CreateAndResolve(true, __func__);
 }
 
+Maybe<nsCString> MediaFormatReader::GetAudioProcessPerCodec() {
+  if (mAudio.mDescription == "uninitialized"_ns) {
+    return Nothing();
+  }
+
+  MOZ_ASSERT(mAudio.mProcessName.Length() > 0,
+             "Should have had a process name");
+  MOZ_ASSERT(mAudio.mCodecName.Length() > 0, "Should have had a codec name");
+
+  nsCString processName = mAudio.mProcessName;
+  nsCString audioProcessPerCodecName(processName + ","_ns + mAudio.mCodecName);
+  if (processName != "utility"_ns) {
+    if (!StaticPrefs::media_rdd_process_enabled()) {
+      audioProcessPerCodecName += ",rdd-disabled"_ns;
+    }
+    if (!StaticPrefs::media_utility_process_enabled()) {
+      audioProcessPerCodecName += ",utility-disabled"_ns;
+    }
+  }
+  return Some(audioProcessPerCodecName);
+}
+
 void MediaFormatReader::GetDebugInfo(dom::MediaFormatReaderDebugInfo& aInfo) {
   MOZ_ASSERT(OnTaskQueue(),
              "Don't call this off the task queue, it's going to touch a lot of "

dom/media/MediaFormatReader.h

@@ -194,6 +194,8 @@ class MediaFormatReader final
   RefPtr<GenericPromise> RequestDebugInfo(
       dom::MediaFormatReaderDebugInfo& aInfo);
 
+  Maybe<nsCString> GetAudioProcessPerCodec();
+
   // Switch the video decoder to NullDecoderModule. It might takes effective
   // since a few samples later depends on how much demuxed samples are already
   // queued in the original video decoder.
@@ -363,7 +365,9 @@ class MediaFormatReader final
         : mOwner(aOwner),
           mType(aType),
           mMutex("DecoderData"),
-          mDescription("shutdown"),
+          mDescription("uninitialized"),
+          mProcessName(""),
+          mCodecName(""),
           mUpdateScheduled(false),
           mDemuxEOS(false),
           mWaitingForData(false),
@@ -407,14 +411,16 @@ class MediaFormatReader final
     // Only non-null up until the decoder is created.
     RefPtr<TaskQueue> mTaskQueue;
 
-    // Mutex protecting mDescription, mDecoder, mTrackDemuxer and mWorkingInfo
-    // as those can be read outside the TaskQueue.
+    // Mutex protecting mDescription, mDecoder, mTrackDemuxer, mWorkingInfo,
+    // mProcessName and mCodecName as those can be read outside the TaskQueue.
     // They are only written on the TaskQueue however, as such mMutex doesn't
     // need to be held when those members are read on the TaskQueue.
     Mutex mMutex MOZ_UNANNOTATED;
     // The platform decoder.
     RefPtr<MediaDataDecoder> mDecoder;
     nsCString mDescription;
+    nsCString mProcessName;
+    nsCString mCodecName;
     void ShutdownDecoder();
 
     // Only accessed from reader's task queue.

ipc/glue/test/browser/head-telemetry.js

@@ -118,7 +118,7 @@ async function verifyTelemetryForProcess(process, codecNames, extraKey = "") {
   // But we dont care really we just want to ensure 0 on RDD, Content and others
   // in the wild.[${codecName}]
   codecNames.forEach(codecName => {
-    Assert.greaterOrEqual(
+    Assert.equal(
       telemetry[MEDIA_AUDIO_PROCESS][`${process},${codecName}${extraKey}`],
       1,
       `${MEDIA_AUDIO_PROCESS} must have the correct value (${process}, ${codecName}).`