Add tear down exit

Author: Cuda-Chen

virtio-snd.c

@@ -276,6 +276,7 @@ typedef struct {
 typedef struct {
     int32_t guest_playing;
     uint32_t stream_id;
+    int8_t is_done;
     pthread_mutex_t ctrl_mutex;
     pthread_cond_t ctrl_cond;
 } vsnd_stream_sel_t;
@@ -494,6 +495,7 @@ static void virtio_snd_read_pcm_prepare(const virtio_snd_pcm_hdr_t *query,
     props->pp.hdr.hdr.code = VIRTIO_SND_R_PCM_PREPARE;
     props->v.guest_playing = 0;
     props->v.stream_id = stream_id;
+    props->v.is_done = 0;
 
     uint32_t channels = props->pp.channels;
     uint32_t rate = pcm_rate_tbl[props->pp.rate];
@@ -626,15 +628,16 @@ static void virtio_snd_read_pcm_release(const virtio_snd_pcm_hdr_t *query,
         }
     }
 
+    props->v.is_done = 1;
+    fprintf(stderr, "pcm_release tear down CNFA\n");
+    CNFAClose(props->audio_host);
+
     /* Tear down stream related locking attributes. */
     pthread_cond_broadcast(&props->v.ctrl_cond);
     pthread_mutex_unlock(&props->v.ctrl_mutex);
     pthread_mutex_destroy(&props->v.ctrl_mutex);
     pthread_cond_destroy(&props->v.ctrl_cond);
 
-    fprintf(stderr, "pcm_release tear down CNFA\n");
-    CNFAClose(props->audio_host);
-
     *plen = 0;
     fprintf(stderr, "pcm_release stop\n");
 }
@@ -685,6 +688,12 @@ static void virtio_snd_cb(struct CNFADriver *dev,
     uint32_t out_buf_sz = framesp * channels;
 
     pthread_mutex_lock(&v_ptr->ctrl_mutex);
+    if (v_ptr->is_done == 1) {
+        fprintf(stderr, "start tear down\n");
+        memset(out, 0, sizeof(*out) * out_buf_sz);
+        goto finally;
+    }
+
     while (v_ptr->guest_playing == 0) {
         fprintf(stderr, "wait ctrl_cond\n");
         memset(out, 0, sizeof(*out) * out_buf_sz);
@@ -696,6 +705,7 @@ static void virtio_snd_cb(struct CNFADriver *dev,
 
     __virtio_snd_frame_dequeue(out, out_buf_bytes, id);
 
+finally:
     pthread_mutex_unlock(&v_ptr->ctrl_mutex);
 }