Bug 673176. Record decoding speed for different image decoders. r=jlebar

--HG--
extra : transplant_source : %1A%1Dav%7C%C5%BF%9B%09%94bl%AC%14%CCpg%24R%AE

modules/libpr0n/decoders/nsGIFDecoder2.cpp

@@ -1096,5 +1096,12 @@ done:
   return;
 }
 
+Telemetry::ID
+nsGIFDecoder2::SpeedHistogram()
+{
+  return Telemetry::IMAGE_DECODE_SPEED_GIF;
+}
+
+
 } // namespace imagelib
 } // namespace mozilla

modules/libpr0n/decoders/nsGIFDecoder2.h

@@ -63,6 +63,7 @@ public:
 
   virtual void WriteInternal(const char* aBuffer, PRUint32 aCount);
   virtual void FinishInternal();
+  virtual Telemetry::ID SpeedHistogram();
 
 private:
   /* These functions will be called when the decoder has a decoded row,

modules/libpr0n/decoders/nsJPEGDecoder.cpp

@@ -153,6 +153,11 @@ nsJPEGDecoder::~nsJPEGDecoder()
           this));
 }
 
+Telemetry::ID
+nsJPEGDecoder::SpeedHistogram()
+{
+  return Telemetry::IMAGE_DECODE_SPEED_JPEG;
+}
 
 void
 nsJPEGDecoder::InitInternal()

modules/libpr0n/decoders/nsJPEGDecoder.h

@@ -93,6 +93,7 @@ public:
   virtual void WriteInternal(const char* aBuffer, PRUint32 aCount);
   virtual void FinishInternal();
 
+  virtual Telemetry::ID SpeedHistogram();
   void NotifyDone();
 
 protected:

modules/libpr0n/decoders/nsPNGDecoder.cpp

@@ -879,5 +879,12 @@ nsPNGDecoder::warning_callback(png_structp png_ptr, png_const_charp warning_msg)
   PR_LOG(gPNGLog, PR_LOG_WARNING, ("libpng warning: %s\n", warning_msg));
 }
 
+Telemetry::ID
+nsPNGDecoder::SpeedHistogram()
+{
+  return Telemetry::IMAGE_DECODE_SPEED_PNG;
+}
+
+
 } // namespace imagelib
 } // namespace mozilla

modules/libpr0n/decoders/nsPNGDecoder.h

@@ -64,6 +64,7 @@ public:
 
   virtual void InitInternal();
   virtual void WriteInternal(const char* aBuffer, PRUint32 aCount);
+  virtual Telemetry::ID SpeedHistogram();
 
   void CreateFrame(png_uint_32 x_offset, png_uint_32 y_offset,
                    PRInt32 width, PRInt32 height,

modules/libpr0n/src/Decoder.h

@@ -156,6 +156,9 @@ public:
   void SetDecodeFlags(PRUint32 aFlags) { mDecodeFlags = aFlags; }
   PRUint32 GetDecodeFlags() { return mDecodeFlags; }
 
+  // Use HistogramCount as an invalid Histogram ID
+  virtual Telemetry::ID SpeedHistogram() { return Telemetry::HistogramCount; }
+
 protected:
 
   /*

modules/libpr0n/src/RasterImage.cpp

@@ -2775,6 +2775,13 @@ imgDecodeWorker::Run()
 
     if (!image->mDecoder->IsSizeDecode()) {
         Telemetry::Accumulate(Telemetry::IMAGE_DECODE_TIME, PRInt32(mDecodeTime.ToMicroseconds()));
+
+        // We only record the speed for some decoders. The rest have SpeedHistogram return HistogramCount.
+        Telemetry::ID id = image->mDecoder->SpeedHistogram();
+        if (id < Telemetry::HistogramCount) {
+            PRInt32 KBps = PRInt32((image->mBytesDecoded/1024.0)/mDecodeTime.ToSeconds());
+            Telemetry::Accumulate(id, KBps);
+        }
     }
 
     rv = image->ShutdownDecoder(RasterImage::eShutdownIntent_Done);

modules/libpr0n/src/RasterImage.h

@@ -65,6 +65,7 @@
 #include "nsThreadUtils.h"
 #include "DiscardTracker.h"
 #include "mozilla/TimeStamp.h"
+#include "mozilla/Telemetry.h"
 #ifdef DEBUG
   #include "imgIContainerDebug.h"
 #endif

toolkit/components/telemetry/TelemetryHistograms.h

@@ -100,6 +100,9 @@ HISTOGRAM(IMAGE_DECODE_TIME,    50, 50000000, 100, EXPONENTIAL, "Time spent deco
 HISTOGRAM(IMAGE_DECODE_ON_DRAW_LATENCY,  50, 50000000, 100, EXPONENTIAL, "Time from starting a decode to it showing up on the screen (us)")
 HISTOGRAM(IMAGE_DECODE_CHUNKS, 1,  500, 50, EXPONENTIAL, "Number of chunks per decode attempt")
 HISTOGRAM(IMAGE_DECODE_COUNT, 1,  500, 50, EXPONENTIAL, "Decode count")
+HISTOGRAM(IMAGE_DECODE_SPEED_JPEG, 500, 50000000,  50, EXPONENTIAL, "JPEG image decode speed (Kbytes/sec)")
+HISTOGRAM(IMAGE_DECODE_SPEED_GIF,  500, 50000000,  50, EXPONENTIAL, "GIF image decode speed (Kbytes/sec)")
+HISTOGRAM(IMAGE_DECODE_SPEED_PNG,  500, 50000000,  50, EXPONENTIAL, "PNG image decode speed (Kbytes/sec)")
 
 HISTOGRAM(CANVAS_2D_USED, 0, 1, 2, BOOLEAN, "2D canvas used")
 HISTOGRAM(CANVAS_WEBGL_USED, 0, 1, 2, BOOLEAN, "WebGL canvas used")