Changeset 88433 in vbox for trunk/src/VBox/Devices/Audio/AudioMixer.h

Timestamp:

Apr 9, 2021 12:55:19 PM (4 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

143685

Message:

Audio: Eliminated the DrvAudio mixing buffers for output streams on devices without their own mixer. Changed the prebuffering to not default to the whole backend buffer size, but only 2/3 of it, so that there is room for a bit of incoming data from the device once we start playing. We don't want to have that gather in the device mixer or internal DMA buffers. This code needs some more testing and work, only tested on linux against ALSA. bugref:9890

File:

• trunk/src/VBox/Devices/Audio/AudioMixer.h (modified) (3 diffs)

trunk/src/VBox/Devices/Audio/AudioMixer.h

@@ -91 +91 @@
     /** The statistics prefix. */
     char                   *pszStatPrefix;
-    /** The streams's critical section. */
-    RTCRITSECT              CritSect;
     /** Sink this stream is attached to. */
     PAUDMIXSINK             pSink;
@@ -103 +101 @@
     /** Pointer to PDM audio stream this mixer stream handles. */
     PPDMAUDIOSTREAM         pStream;
+    /** Mixing buffer peeking state & config. */
+    AUDIOMIXBUFPEEKSTATE    PeekState;
     /** Last read (recording) / written (playback) timestamp (in ns). */
     uint64_t                tsLastReadWrittenNs;
-    /** The stream's circular buffer for temporarily
-     *  holding (raw) device audio data. */
-    PRTCIRCBUF              pCircBuf;
-    /** Stats: Number of bytes used in the circular buffer. */
-    uint32_t                StatsCircBufUsed;
-    /** Stats: Size of circular buffer. */
-    uint32_t                StatsCircBufSize;
+    /** The streams's critical section. */
+    RTCRITSECT              CritSect;
 } AUDMIXSTREAM, *PAUDMIXSTREAM;
 
@@ -124 +119 @@
 #define AUDMIXSINK_STS_PENDING_DISABLE       RT_BIT(1)
 /** Dirty flag.
- *  For output sinks this means that there is data in the
- *  sink which has not been played yet.
- *  For input sinks this means that there is data in the
- *  sink which has been recorded but not transferred to the
- *  destination yet. */
+ * - For output sinks this means that there is data in the sink which has not
+ *   been played yet.
+ * - For input sinks this means that there is data in the sink which has been
+ *   recorded but not transferred to the destination yet. */
 #define AUDMIXSINK_STS_DIRTY                 RT_BIT(2)
 
 /**
  * Audio mixer sink direction.
+ * @todo r=bird: use PDMAUDIODIR instead.
  */
 typedef enum AUDMIXSINKDIR