Add compiler barrier

Author: Cuda-Chen

virtio-snd.c

@@ -298,7 +298,10 @@ typedef struct {
     // PCM frame ring buffer
     virtio_snd_ring_buffer_t ring;
 } virtio_snd_prop_t;
-#define VSND_COMPILER_BARRIER asm("" ::: "memory")
+#define VSND_COMPILER_BARRIER \
+    do {                      \
+        asm("" ::: "memory"); \
+    } while (0)
 
 static virtio_snd_config_t vsnd_configs[VSND_DEV_CNT_MAX];
 static virtio_snd_prop_t vsnd_props[VSND_DEV_CNT_MAX] = {
@@ -505,7 +508,7 @@ static void virtio_snd_read_pcm_prepare(const virtio_snd_pcm_hdr_t *query,
         CNFAInit(NULL, "semu-virtio-snd", virtio_snd_cb,
                  pcm_rate_tbl[vsnd_props[stream_id].pp.rate], 0, 1, 0,
                  buffer_bytes, NULL, NULL, &v);
-    uint32_t sz = buffer_bytes;
+    uint32_t sz = buffer_bytes * 3;
     vsnd_props[stream_id].ring.buffer = (void *) malloc(sizeof(void) * sz);
     vsnd_props[stream_id].ring.prod.head = 0;
     vsnd_props[stream_id].ring.prod.tail = 0;
@@ -598,7 +601,7 @@ static void virtio_snd_read_pcm_release(const virtio_snd_pcm_hdr_t *query,
 double omega = 0.0;
 int totalframesp = 0;
 int totalframesr = 0;
-static void __virtio_snd_frame_dequeue(void *out,
+static void __virtio_snd_frame_dequeue(short *out,
                                        uint32_t n,
                                        uint32_t stream_id)
 {
@@ -616,7 +619,10 @@ static void __virtio_snd_frame_dequeue(void *out,
     entries = prod_tail - cons_head;
 
     if (n > entries)
-        fprintf(stderr, "copy length is larget than entries\n");
+        fprintf(stderr,
+                "consumer payload length %" PRIu32
+                " larger than entries %" PRIu32 "\n",
+                n, entries);
 
     cons_next = cons_head + n;
     props->ring.cons.head = cons_next;
@@ -630,12 +636,9 @@ static void __virtio_snd_frame_dequeue(void *out,
             cons_head, cons_next, mask, idx);
     if (idx + n < size) {
         memcpy(out, props->ring.buffer + idx, n);
-        // out += n;
     } else {
         memcpy(out, props->ring.buffer + idx, size - idx);
-        // out += (size - idx);
         memcpy(out + (size - idx), props->ring.buffer, n - (size - idx));
-        // out += (n - (size - idx));
     }
     VSND_COMPILER_BARRIER;
 
@@ -802,19 +805,19 @@ static void __virtio_snd_frame_enqueue(void *payload,
     /* Move prod_head. */
     if (n > free_entries)
         fprintf(stderr,
-                "payload length %" PRIu32 " larger than free_entries %" PRIu32
-                "\n",
+                "producer payload length %" PRIu32
+                " larger than free_entries %" PRIu32 "\n",
                 n, free_entries);
     prod_next = prod_head + n;
     props->ring.prod.head = prod_next;
 
     /* Write payload to ring buffer. */
     uint32_t size = props->ring.prod.size;
     uint32_t idx = prod_head % size;
-    fprintf(stderr,
+    /*fprintf(stderr,
             "prod_head %" PRIu32 " prod_next %" PRIu32 " mask %" PRIu32
             " idx %" PRIu32 "\n",
-            prod_head, prod_next, mask, idx);
+            prod_head, prod_next, mask, idx);*/
     if (idx + n < size) {
         memcpy(props->ring.buffer + idx, payload, n);
     } else {