Can now indicate the desired number of notifications (sub-buffers)
per fast track buffer when using the default buffer size.
There is no change for normal tracks, or fast tracks with a non-default buffer size.
Also fix related bugs:
Notification period was not set correctly when fast multiplier is not 1.
Incorrect warning when client adjusted notification frames.
Bug: 27819623
Bug: 28117362
Change-Id: Ifc2121e874f51718cd56ec04e4bd5f89f4963132
diff --git a/services/audioflinger/Threads.cpp b/services/audioflinger/Threads.cpp
index ff67fb2..3fdf99f 100644
--- a/services/audioflinger/Threads.cpp
+++ b/services/audioflinger/Threads.cpp
@@ -182,13 +182,9 @@
static const int kPriorityFastMixer = 3;
static const int kPriorityFastCapture = 3;
-// IAudioFlinger::createTrack() reports back to client the total size of shared memory area
-// for the track. The client then sub-divides this into smaller buffers for its use.
-// Currently the client uses N-buffering by default, but doesn't tell us about the value of N.
-// So for now we just assume that client is double-buffered for fast tracks.
-// FIXME It would be better for client to tell AudioFlinger the value of N,
-// so AudioFlinger could allocate the right amount of memory.
-// See the client's minBufCount and mNotificationFramesAct calculations for details.
+// IAudioFlinger::createTrack() has an in/out parameter 'pFrameCount' for the total size of the
+// track buffer in shared memory. Zero on input means to use a default value. For fast tracks,
+// AudioFlinger derives the default from HAL buffer size and 'fast track multiplier'.
// This is the default value, if not specified by property.
static const int kFastTrackMultiplier = 2;