Merge remote-tracking branch 'remotes/kraxel/tags/audio-20200923-pull-request' into staging

audio: various buffering fixes.
audio: build spiceaudio as module.

# gpg: Signature made Wed 23 Sep 2020 10:09:46 BST
# gpg:                using RSA key 4CB6D8EED3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>" [full]
# gpg:                 aka "Gerd Hoffmann <gerd@kraxel.org>" [full]
# gpg:                 aka "Gerd Hoffmann (private) <kraxel@gmail.com>" [full]
# Primary key fingerprint: A032 8CFF B93A 17A7 9901  FE7D 4CB6 D8EE D3E8 7138

* remotes/kraxel/tags/audio-20200923-pull-request:
  audio: build spiceaudio as module
  audio: remove qemu_spice_audio_init()
  audio: run downstream playback queue unconditionally
  audio: align audio_generic_write with audio_pcm_hw_run_out
  audio: remove unnecessary calls to put_buffer_in
  audio: align audio_generic_read with audio_pcm_hw_run_in
  audio/spiceaudio: always rate limit playback stream
  audio/audio: fix video playback slowdown with spiceaudio
  audio: handle buf == NULL in put_buffer_out()

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

3 files changed, 80 insertions, 30 deletions

diff --git a/audio/audio.c b/audio/audio.c
index 1a68cfaafb..46578e4a58 100644
--- a/audio/audio.c
+++ b/audio/audio.c
@@ -34,6 +34,7 @@
 #include "qemu/module.h"
 #include "sysemu/replay.h"
 #include "sysemu/runstate.h"
+#include "ui/qemu-spice.h"
 #include "trace.h"
 
 #define AUDIO_CAP "audio"
@@ -1089,14 +1090,18 @@ static size_t audio_pcm_hw_run_out(HWVoiceOut *hw, size_t live)
     size_t clipped = 0;
 
     while (live) {
-        size_t size, decr, proc;
+        size_t size = live * hw->info.bytes_per_frame;
+        size_t decr, proc;
         void *buf = hw->pcm_ops->get_buffer_out(hw, &size);
-        if (!buf || size == 0) {
+
+        if (size == 0) {
             break;
         }
 
         decr = MIN(size / hw->info.bytes_per_frame, live);
-        audio_pcm_hw_clip_out(hw, buf, decr);
+        if (buf) {
+            audio_pcm_hw_clip_out(hw, buf, decr);
+        }
         proc = hw->pcm_ops->put_buffer_out(hw, buf,
                                            decr * hw->info.bytes_per_frame) /
             hw->info.bytes_per_frame;
@@ -1182,6 +1187,9 @@ static void audio_run_out (AudioState *s)
                     }
                 }
             }
+            if (hw->pcm_ops->run_buffer_out) {
+                hw->pcm_ops->run_buffer_out(hw);
+            }
             continue;
         }
 
@@ -1257,7 +1265,6 @@ static size_t audio_pcm_hw_run_in(HWVoiceIn *hw, size_t samples)
 
         assert(size % hw->info.bytes_per_frame == 0);
         if (size == 0) {
-            hw->pcm_ops->put_buffer_in(hw, buf, size);
             break;
         }
 
@@ -1481,22 +1488,54 @@ size_t audio_generic_put_buffer_out(HWVoiceOut *hw, void *buf, size_t size)
 
 size_t audio_generic_write(HWVoiceOut *hw, void *buf, size_t size)
 {
-    size_t dst_size, copy_size;
-    void *dst = hw->pcm_ops->get_buffer_out(hw, &dst_size);
-    copy_size = MIN(size, dst_size);
+    size_t total = 0;
+
+    while (total < size) {
+        size_t dst_size = size - total;
+        size_t copy_size, proc;
+        void *dst = hw->pcm_ops->get_buffer_out(hw, &dst_size);
+
+        if (dst_size == 0) {
+            break;
+        }
+
+        copy_size = MIN(size - total, dst_size);
+        if (dst) {
+            memcpy(dst, (char *)buf + total, copy_size);
+        }
+        proc = hw->pcm_ops->put_buffer_out(hw, dst, copy_size);
+        total += proc;
+
+        if (proc == 0 || proc < copy_size) {
+            break;
+        }
+    }
 
-    memcpy(dst, buf, copy_size);
-    return hw->pcm_ops->put_buffer_out(hw, dst, copy_size);
+    if (hw->pcm_ops->run_buffer_out) {
+        hw->pcm_ops->run_buffer_out(hw);
+    }
+
+    return total;
 }
 
 size_t audio_generic_read(HWVoiceIn *hw, void *buf, size_t size)
 {
-    void *src = hw->pcm_ops->get_buffer_in(hw, &size);
+    size_t total = 0;
 
-    memcpy(buf, src, size);
-    hw->pcm_ops->put_buffer_in(hw, src, size);
+    while (total < size) {
+        size_t src_size = size - total;
+        void *src = hw->pcm_ops->get_buffer_in(hw, &src_size);
 
-    return size;
+        if (src_size == 0) {
+            break;
+        }
+
+        memcpy((char *)buf + total, src, src_size);
+        hw->pcm_ops->put_buffer_in(hw, src, src_size);
+        total += src_size;
+    }
+
+    return total;
 }
 
 static int audio_driver_init(AudioState *s, struct audio_driver *drv,
@@ -1658,6 +1697,21 @@ static AudioState *audio_init(Audiodev *dev, const char *name)
     /* silence gcc warning about uninitialized variable */
     AudiodevListHead head = QSIMPLEQ_HEAD_INITIALIZER(head);
 
+    if (using_spice) {
+        /*
+         * When using spice allow the spice audio driver being picked
+         * as default.
+         *
+         * Temporary hack.  Using audio devices without explicit
+         * audiodev= property is already deprecated.  Same goes for
+         * the -soundhw switch.  Once this support gets finally
+         * removed we can also drop the concept of a default audio
+         * backend and this can go away.
+         */
+        driver = audio_driver_lookup("spice");
+        driver->can_be_default = 1;
+    }
+
     if (dev) {
         /* -audiodev option */
         legacy_config = false;
diff --git a/audio/meson.build b/audio/meson.build
index 15c06ba045..18a831129e 100644
--- a/audio/meson.build
+++ b/audio/meson.build
@@ -7,7 +7,6 @@ softmmu_ss.add(files(
   'wavcapture.c',
 ))
 
-softmmu_ss.add(when: [spice, 'CONFIG_SPICE'], if_true: files('spiceaudio.c'))
 softmmu_ss.add(when: [coreaudio, 'CONFIG_AUDIO_COREAUDIO'], if_true: files('coreaudio.c'))
 softmmu_ss.add(when: [dsound, 'CONFIG_AUDIO_DSOUND'], if_true: files('dsoundaudio.c'))
 softmmu_ss.add(when: ['CONFIG_AUDIO_WIN_INT'], if_true: files('audio_win_int.c'))
@@ -18,7 +17,8 @@ foreach m : [
   ['CONFIG_AUDIO_OSS', 'oss', oss, 'ossaudio.c'],
   ['CONFIG_AUDIO_PA', 'pa', pulse, 'paaudio.c'],
   ['CONFIG_AUDIO_SDL', 'sdl', sdl, 'sdlaudio.c'],
-  ['CONFIG_AUDIO_JACK', 'jack', jack, 'jackaudio.c']
+  ['CONFIG_AUDIO_JACK', 'jack', jack, 'jackaudio.c'],
+  ['CONFIG_SPICE', 'spice', spice, 'spiceaudio.c']
 ]
   if config_host.has_key(m[0])
     module_ss = ss.source_set()
diff --git a/audio/spiceaudio.c b/audio/spiceaudio.c
index b6b5da4812..ed6dff1dcc 100644
--- a/audio/spiceaudio.c
+++ b/audio/spiceaudio.c
@@ -130,12 +130,11 @@ static void *line_out_get_buffer(HWVoiceOut *hw, size_t *size)
     }
 
     if (out->frame) {
-        *size = audio_rate_get_bytes(
-            &hw->info, &out->rate,
-            (out->fsize - out->fpos) * hw->info.bytes_per_frame);
-    } else {
-        audio_rate_start(&out->rate);
+        *size = MIN((out->fsize - out->fpos) << 2, *size);
     }
+
+    *size = audio_rate_get_bytes(&hw->info, &out->rate, *size);
+
     return out->frame + out->fpos;
 }
 
@@ -143,12 +142,14 @@ static size_t line_out_put_buffer(HWVoiceOut *hw, void *buf, size_t size)
 {
     SpiceVoiceOut *out = container_of(hw, SpiceVoiceOut, hw);
 
-    assert(buf == out->frame + out->fpos && out->fpos <= out->fsize);
-    out->fpos += size >> 2;
+    if (buf) {
+        assert(buf == out->frame + out->fpos && out->fpos <= out->fsize);
+        out->fpos += size >> 2;
 
-    if (out->fpos == out->fsize) { /* buffer full */
-        spice_server_playback_put_samples(&out->sin, out->frame);
-        out->frame = NULL;
+        if (out->fpos == out->fsize) { /* buffer full */
+            spice_server_playback_put_samples(&out->sin, out->frame);
+            out->frame = NULL;
+        }
     }
 
     return size;
@@ -310,11 +311,6 @@ static struct audio_driver spice_audio_driver = {
     .voice_size_in  = sizeof (SpiceVoiceIn),
 };
 
-void qemu_spice_audio_init (void)
-{
-    spice_audio_driver.can_be_default = 1;
-}
-
 static void register_audio_spice(void)
 {
     audio_driver_register(&spice_audio_driver);