[Qemu-devel] [PATCH] audio: disable timer when idle.

[Gerd Hoffmann <kraxel@redhat.com>]

This patch makes sure the audio timer gets disabled when no voice is
active.  It adds a variable to track whenever the timer is needed or
not to the global audio state.  audio_timer_reset() will set that
variable.  audio_timer() will check that variable and only re-arm
the timer when needed.  One additional call to audio_timer_reset() has
been added to the output voice disable code path.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 audio/audio.c     |    6 +++++-
 audio/audio_int.h |    1 +
 2 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/audio/audio.c b/audio/audio.c
index ade342e..9cf91ae 100644
--- a/audio/audio.c
+++ b/audio/audio.c
@@ -1101,7 +1101,8 @@ static void audio_timer (void *opaque)
     AudioState *s = opaque;
 
     audio_run ("timer");
-    qemu_mod_timer (s->ts, qemu_get_clock (vm_clock) + conf.period.ticks);
+    if (s->need_timer)
+        qemu_mod_timer (s->ts, qemu_get_clock (vm_clock) + conf.period.ticks);
 }
 
 
@@ -1124,9 +1125,11 @@ static void audio_reset_timer (void)
     AudioState *s = &glob_audio_state;
 
     if (audio_is_timer_needed ()) {
+        s->need_timer = 1;
         qemu_mod_timer (s->ts, qemu_get_clock (vm_clock) + 1);
     }
     else {
+        s->need_timer = 0;
         qemu_del_timer (s->ts);
     }
 }
@@ -1380,6 +1383,7 @@ static void audio_run_out (AudioState *s)
                 sc->sw.active = 0;
                 audio_recalc_and_notify_capture (sc->cap);
             }
+            audio_reset_timer ();
             continue;
         }
 
diff --git a/audio/audio_int.h b/audio/audio_int.h
index d66f2c3..df060a9 100644
--- a/audio/audio_int.h
+++ b/audio/audio_int.h
@@ -190,6 +190,7 @@ struct AudioState {
     void *drv_opaque;
 
     QEMUTimer *ts;
+    int need_timer;
     QLIST_HEAD (card_listhead, QEMUSoundCard) card_head;
     QLIST_HEAD (hw_in_listhead, HWVoiceIn) hw_head_in;
     QLIST_HEAD (hw_out_listhead, HWVoiceOut) hw_head_out;
-- 
1.7.1