在 2022/8/17 21:57, Guo Zhi 写道:
Vsock uses buffers in order, and for tx driver doesn't have to
know the length of the buffer. So we can do a batch for vsock if
in order negotiated, only write one used ring for a batch of buffers
Signed-off-by: Guo Zhi <qtxuning1999@xxxxxxxxxxx>
---
drivers/vhost/vsock.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c
index 368330417bde..b0108009c39a 100644
--- a/drivers/vhost/vsock.c
+++ b/drivers/vhost/vsock.c
@@ -500,6 +500,7 @@ static void vhost_vsock_handle_tx_kick(struct vhost_work *work)
int head, pkts = 0, total_len = 0;
unsigned int out, in;
bool added = false;
+ int last_head = -1;
mutex_lock(&vq->mutex);
@@ -551,10 +552,16 @@ static void vhost_vsock_handle_tx_kick(struct vhost_work *work)
else
virtio_transport_free_pkt(pkt);
- vhost_add_used(vq, head, 0);
+ if (!vhost_has_feature(vq, VIRTIO_F_IN_ORDER))
+ vhost_add_used(vq, head, 0);
+ else
+ last_head = head;
added = true;
} while(likely(!vhost_exceeds_weight(vq, ++pkts, total_len)));
+ /* If in order feature negotiaged, we can do a batch to increase performance */
+ if (vhost_has_feature(vq, VIRTIO_F_IN_ORDER) && last_head != -1)
+ vhost_add_used(vq, last_head, 0);
I may miss something but spec said "The device then skips forward in the
ring according to the size of the batch. ".
I don't see how it is done here.
Thanks
no_more_replies:
if (added)
vhost_signal(&vsock->dev, vq);
