Add histogram for percentage of incoming frames that are limited in resolution due to cpu

webrtc/media/engine/webrtcvideoengine2.cc

Index: webrtc/media/engine/webrtcvideoengine2.cc
diff --git a/webrtc/media/engine/webrtcvideoengine2.cc b/webrtc/media/engine/webrtcvideoengine2.cc
index 4a72ef61398a73eacad9667ad0633586dbdda6d6..47259e0cab32a3d10921866ebb82a706ea791fef 100644
--- a/webrtc/media/engine/webrtcvideoengine2.cc
+++ b/webrtc/media/engine/webrtcvideoengine2.cc
@@ -31,6 +31,7 @@
 #include "webrtc/modules/video_coding/codecs/vp8/simulcast_encoder_adapter.h"
 #include "webrtc/modules/video_coding/codecs/vp9/include/vp9.h"
 #include "webrtc/system_wrappers/include/field_trial.h"
+#include "webrtc/system_wrappers/include/metrics.h"
 #include "webrtc/video_decoder.h"
 #include "webrtc/video_encoder.h"
 
@@ -1576,6 +1577,8 @@ WebRtcVideoChannel2::WebRtcVideoSendStream::WebRtcVideoSendStream(
       call_(call),
       cpu_restricted_counter_(0),
       number_of_cpu_adapt_changes_(0),
+      frames_(0),
+      cpu_restricted_frames_(0),
       source_(nullptr),
       external_encoder_factory_(external_encoder_factory),
       stream_(nullptr),
@@ -1621,6 +1624,16 @@ WebRtcVideoChannel2::WebRtcVideoSendStream::~WebRtcVideoSendStream() {
     call_->DestroyVideoSendStream(stream_);
   }
   DestroyVideoEncoder(&allocated_encoder_);
+  UpdateHistograms();
+}
+
+void WebRtcVideoChannel2::WebRtcVideoSendStream::UpdateHistograms() const {
+  const int kMinRequiredFrames = 200;
+  if (frames_ > kMinRequiredFrames) {
+    RTC_LOGGED_HISTOGRAM_PERCENTAGE(
+        "WebRTC.Video.CpuLimitedResolutionInPercent",
+        cpu_restricted_frames_ * 100 / frames_);

[perkj_webrtc, 2016/08/22 09:06:42]

suggest rename frames_ to frame_count_. Suggest to change cpu_restricted_frames
to cpu_restricted_frame_count_

[åsapersson, 2016/08/22 09:41:51]

Done.

+  }
 }
 
 void WebRtcVideoChannel2::WebRtcVideoSendStream::OnFrame(
@@ -1675,6 +1688,10 @@ void WebRtcVideoChannel2::WebRtcVideoSendStream::OnFrame(
     return;
   }
 
+  ++frames_;

[perkj_webrtc, 2016/08/22 09:06:42]

frames_ and cpu_restricted_frames_ will be written by the camera thread and and
read by the worker thread in thi s cl.
Easiest way that is consistent with the rest in this file is probably just to
declare frames_  cpu_restricted_frames_ as GUARDED_BY(&lock_) and take lock in
UpdateHistograms if that is safe.  

[åsapersson, 2016/08/22 09:41:51]

Added guarded_by (and exclusive_lock_required for UpdateHistograms since called
from destructor).

+  if (cpu_restricted_counter_ > 0)

[perkj_webrtc, 2016/08/19 13:14:46]

Would it be possible to do this in ViEEncoder instead? I am trying to remove all
dependencies to frames from this class and express CPU adaptation in ViEEncoder
as VideoSinkWants.

[åsapersson, 2016/08/22 07:56:29]

Could it be done in a separate/follow up CL when the cpu adaptation is expressed
in ViEEncoder?

[perkj_webrtc, 2016/08/22 09:06:42]

sure.

+    ++cpu_restricted_frames_;
+
   stream_->Input()->IncomingCapturedFrame(video_frame);
 }