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Author: Cuda-Chen

virtio-snd.c

@@ -292,6 +292,7 @@ typedef struct {
     // PCM frame ring buffer
     virtio_snd_ring_buffer_t ring;
 } virtio_snd_prop_t;
+#define VSND_COMPILER_BARRIER asm("" ::: "memory")
 
 static virtio_snd_config_t vsnd_configs[VSND_DEV_CNT_MAX];
 static virtio_snd_prop_t vsnd_props[VSND_DEV_CNT_MAX] = {
@@ -610,7 +611,7 @@ static void __virtio_snd_frame_dequeue(void *out,
         memcpy(out, props->ring.buffer + idx, size - idx);
         memcpy(out + (size - idx), props->ring.buffer, n - (size - idx));
     }
-    asm("" ::: "memory");
+    VSND_COMPILER_BARRIER;
 
     props->ring.cons.tail = cons_next;
 }
@@ -788,7 +789,7 @@ static void __virtio_snd_frame_enqueue(void *payload,
         memcpy(props->ring.buffer + idx, payload, size - idx);
         memcpy(props->ring.buffer, payload, n - (size - idx));
     }
-    asm("" ::: "memory");
+    VSND_COMPILER_BARRIER;
 
     /* Update prod_tail */
     props->ring.prod.tail = prod_next;