On Fri, Sep 21, 2018 at 08:26:58PM +0800, Tiwei Bie wrote:
On Fri, Sep 21, 2018 at 12:33:03PM +0200, Jens Freimann wrote:
[...]
static inline int
-desc_is_used(struct vring_desc_packed *desc, struct vring *vr)
+_desc_is_used(struct vring_desc_packed *desc)
{
uint16_t used, avail;
used = !!(desc->flags & VRING_DESC_F_USED(1));
avail = !!(desc->flags & VRING_DESC_F_AVAIL(1));
- return used == avail && used == vr->used_wrap_counter;
+ return used == avail;
+
+}
+
+static inline int
+desc_is_used(struct vring_desc_packed *desc, struct vring *vr)
+{
+ uint16_t used;
+
+ used = !!(desc->flags & VRING_DESC_F_USED(1));
+
+ return _desc_is_used(desc) && used == vr->used_wrap_counter;
}
/* The standard layout for the ring is a continuous chunk of memory which
diff --git a/drivers/net/virtio/virtio_rxtx.c b/drivers/net/virtio/virtio_rxtx.c
index eb891433e..ea6300563 100644
--- a/drivers/net/virtio/virtio_rxtx.c
+++ b/drivers/net/virtio/virtio_rxtx.c
@@ -38,6 +38,7 @@
#define VIRTIO_DUMP_PACKET(m, len) do { } while (0)
#endif
+
int
virtio_dev_rx_queue_done(void *rxq, uint16_t offset)
{
@@ -165,6 +166,31 @@ virtqueue_dequeue_rx_inorder(struct virtqueue *vq,
#endif
/* Cleanup from completed transmits. */
+static void
+virtio_xmit_cleanup_packed(struct virtqueue *vq)
+{
+ uint16_t idx;
+ uint16_t size = vq->vq_nentries;
+ struct vring_desc_packed *desc = vq->vq_ring.desc_packed;
+ struct vq_desc_extra *dxp;
+
+ idx = vq->vq_used_cons_idx;
+ while (_desc_is_used(&desc[idx]) &&
We can't just compare the AVAIL bit and USED bit to
check whether a desc is used.
We can't compare with the current wrap counter value as well
because it won't match the flags in descriptors. So check against
used_wrap_counter ^= 1 then?
+ vq->vq_free_cnt < size) {
+ dxp = &vq->vq_descx[idx];
The code is still assuming the descs will be written
back by device in order. The vq->vq_descx[] needs to
be managed e.g. as a list to support the out-of-order
processing. IOW, we can't assume vq->vq_descx[idx]
is corresponding to desc[idx] when device may write
back the descs out of order.
I changed it to not assume this in other spots but missed this one. I
will check more carefully and add code to make vq_descx entries a list.
Thanks for the review!
regards,
Jens
