Changeset 88159 in vbox for trunk/src/VBox

Timestamp:

Mar 17, 2021 2:42:40 PM (4 years ago)

Author:

vboxsync

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

143308

Message:

DevHDA: Restructured the input DMA code, getting rid of the FIFO bounce buffering and adding a silence pre-buffering period at the start of the stream (till we get a bit of data from the host device). [fix] bugref:9890

File:

• trunk/src/VBox/Devices/Audio/HDAStream.cpp (modified) (3 diffs)

trunk/src/VBox/Devices/Audio/HDAStream.cpp

@@ -1573 +1573 @@
 static void hdaR3StreamPullFromMixer(PHDASTREAM pStreamShared, PHDASTREAMR3 pStreamR3, PAUDMIXSINK pSink)
 {
+    RT_NOREF(pStreamShared);
     int rc = AudioMixerSinkUpdate(pSink);
     AssertRC(rc);
@@ -2286 +2287 @@
             if (pStreamShared->State.fInputPreBuffered && cbStreamUsed >= cbPeriod)
             { /*likely*/ }
-            /* Because it may take a while for the input stream to get going (at
-               least with pulseaudio), we feed the guest silence till we've
-               pre-buffer a reasonable amount of audio. */
+            /*
+             * Because it may take a while for the input stream to get going (at
+             * least with pulseaudio), we feed the guest silence till we've
+             * pre-buffer a reasonable amount of audio.
+             */
             else if (!pStreamShared->State.fInputPreBuffered)
             {
@@ -2312 +2315 @@
             else
             {
+                /** @todo We're ending up here to frequently with pulse audio at least (just
+                 *        watch the stream stats in the statistcs viewer, and way to often we
+                 *        have to inject silence bytes.  I suspect part of the problem is
+                 *        that the HDA device require a much better latency than what the
+                 *        pulse audio is configured for by default (10 ms vs 150ms). */
                 STAM_REL_COUNTER_INC(&pStreamR3->State.StatDmaFlowProblems);
                 Log(("hdaR3StreamUpdate: Warning! Stream #%u has insufficient data available: %u bytes, need %u.  Will try move pull more data into the buffer...\n",