Only add to used ring when a batch a buffer have all been used. And if
in order feature negotiated, add randomness to the used buffer's order,
test the ability of vhost to reorder batched buffer.
Signed-off-by: Guo Zhi <qtxuning1999@xxxxxxxxxxx>
---
drivers/vhost/test.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/drivers/vhost/test.c b/drivers/vhost/test.c
index bc8e7fb1e..1c9c40c11 100644
--- a/drivers/vhost/test.c
+++ b/drivers/vhost/test.c
@@ -43,6 +43,9 @@ struct vhost_test {
static void handle_vq(struct vhost_test *n)
{
struct vhost_virtqueue *vq = &n->vqs[VHOST_TEST_VQ];
+ struct vring_used_elem *heads = kmalloc(sizeof(*heads)
+ * vq->num, GFP_KERNEL);
+ int batch_idx = 0;
unsigned out, in;
int head;
size_t len, total_len = 0;
@@ -84,11 +87,21 @@ static void handle_vq(struct vhost_test *n)
vq_err(vq, "Unexpected 0 len for TX\n");
break;
}
- vhost_add_used_and_signal(&n->dev, vq, head, 0);
+ heads[batch_idx].id = cpu_to_vhost32(vq, head);
+ heads[batch_idx++].len = cpu_to_vhost32(vq, len);
total_len += len;
if (unlikely(vhost_exceeds_weight(vq, 0, total_len)))
break;
}
+ if (batch_idx) {
+ if (vhost_has_feature(vq, VIRTIO_F_IN_ORDER) && batch_idx >= 2) {
+ vhost_add_used_and_signal_n(&n->dev, vq, &heads[batch_idx / 2],
+ batch_idx - batch_idx / 2);
+ vhost_add_used_and_signal_n(&n->dev, vq, heads, batch_idx / 2);
+ } else {
+ vhost_add_used_and_signal_n(&n->dev, vq, heads, batch_idx);
+ }
+ }
mutex_unlock(&vq->mutex);
}
--
2.17.1
