* Called within rcu_read_lock(). */
static int virtio_queue_empty_rcu(VirtQueue *vq)
{
+ if (unlikely(!vq->vring.avail)) {
+ return 1;
+ }
+
if (vq->shadow_avail_idx != vq->last_avail_idx) {
return 0;
}
{
bool empty;
+ if (unlikely(!vq->vring.avail)) {
+ return 1;
+ }
+
if (vq->shadow_avail_idx != vq->last_avail_idx) {
return 0;
}
return;
}
+ if (unlikely(!vq->vring.used)) {
+ return;
+ }
+
idx = (idx + vq->used_idx) % vq->vring.num;
uelem.id = elem->index;
return;
}
+ if (unlikely(!vq->vring.used)) {
+ return;
+ }
+
/* Make sure buffer is written before we update index. */
smp_wmb();
trace_virtqueue_flush(vq, count);
int64_t len = 0;
int rc;
+ if (unlikely(!vq->vring.desc)) {
+ if (in_bytes) {
+ *in_bytes = 0;
+ }
+ if (out_bytes) {
+ *out_bytes = 0;
+ }
+ return;
+ }
+
rcu_read_lock();
idx = vq->last_avail_idx;
total_bufs = in_total = out_total = 0;