Hi Chenbo,
I'll fix these issues in next version.
For the name, I think maybe we can use 'rte_vhost_clear_queue_thread_unsafe'.
Thanks,
Cheng
> -----Original Message-----
> From: Xia, Chenbo <chenbo....@intel.com>
> Sent: Friday, July 16, 2021 4:56 PM
> To: Jiang, Cheng1 <cheng1.ji...@intel.com>; maxime.coque...@redhat.com
> Cc: dev@dpdk.org; Hu, Jiayu <jiayu...@intel.com>; Yang, YvonneX
> <yvonnex.y...@intel.com>
> Subject: RE: [PATCH v4 2/5] vhost: add unsafe API to drain pkts in async vhost
>
> Hi Cheng,
>
> > -----Original Message-----
> > From: Jiang, Cheng1 <cheng1.ji...@intel.com>
> > Sent: Friday, July 16, 2021 10:59 AM
> > To: maxime.coque...@redhat.com; Xia, Chenbo <chenbo....@intel.com>
> > Cc: dev@dpdk.org; Hu, Jiayu <jiayu...@intel.com>; Yang, YvonneX
> > <yvonnex.y...@intel.com>; Jiang, Cheng1 <cheng1.ji...@intel.com>
> > Subject: [PATCH v4 2/5] vhost: add unsafe API to drain pkts in async
> > vhost
> >
> > Applications need to stop DMA transfers and finish all the in-flight
> > pkts when in VM memory hot-plug case and async vhost is used. This
>
> Pkts -> packets
>
> > patch is to provide an unsafe API to drain in-flight pkts which are
>
> Ditto
>
> > submitted to DMA engine in vhost async data path.
> >
> > Signed-off-by: Cheng Jiang <cheng1.ji...@intel.com>
> > ---
> > lib/vhost/rte_vhost_async.h | 24 ++++++++++
> > lib/vhost/version.map | 3 ++
> > lib/vhost/virtio_net.c | 90 +++++++++++++++++++++++++++----------
> > 3 files changed, 94 insertions(+), 23 deletions(-)
> >
> > diff --git a/lib/vhost/rte_vhost_async.h b/lib/vhost/rte_vhost_async.h
> > index bc81cd0caa..fd622631b2 100644
> > --- a/lib/vhost/rte_vhost_async.h
> > +++ b/lib/vhost/rte_vhost_async.h
> > @@ -193,4 +193,28 @@ __rte_experimental uint16_t
> > rte_vhost_poll_enqueue_completed(int vid, uint16_t queue_id,
> > struct rte_mbuf **pkts, uint16_t count);
> >
> > +/**
> > + * This function checks async completion status and empty all pakcets
>
> Pakcets -> packets
>
> > + * for a specific vhost device queue. Packets which are inflight will
> > + * be returned in an array.
> > + *
> > + * @note This function does not perform any locking
> > + *
> > + * @param vid
> > + * id of vhost device to enqueue data
>
> id -> ID
>
> to drain data?
>
> > + * @param queue_id
> > + * queue id to enqueue data
>
> Ditto
>
> > + * @param pkts
> > + * blank array to get return packet pointer
>
> Return -> returned
>
> > + * @param count
> > + * size of the packet array
> > + * @param times
> > + * max number of poll attempts
> > + * @return
> > + * num of packets returned
>
> num -> Number
>
> And please use capital for first character in each line of param description.
>
> > + */
> > +__rte_experimental
> > +uint16_t rte_vhost_try_drain_queue_thread_unsafe(int vid, uint16_t
> > +queue_id,
>
> I think 'rte_vhost_drain_queue_thread_unsafe' is better?
>
> > + struct rte_mbuf **pkts, uint16_t count, uint16_t times);
> > +
> > #endif /* _RTE_VHOST_ASYNC_H_ */
> > diff --git a/lib/vhost/version.map b/lib/vhost/version.map index
> > 9103a23cd4..b8fc8770dd 100644
> > --- a/lib/vhost/version.map
> > +++ b/lib/vhost/version.map
> > @@ -79,4 +79,7 @@ EXPERIMENTAL {
> >
> > # added in 21.05
> > rte_vhost_get_negotiated_protocol_features;
> > +
> > + # added in 21.08
> > + rte_vhost_try_drain_queue_thread_unsafe;
> > };
> > diff --git a/lib/vhost/virtio_net.c b/lib/vhost/virtio_net.c index
> > 8156796a46..9f541679b9 100644
> > --- a/lib/vhost/virtio_net.c
> > +++ b/lib/vhost/virtio_net.c
> > @@ -2115,10 +2115,10 @@ write_back_completed_descs_packed(struct
> > vhost_virtqueue *vq,
> > } while (nr_left > 0);
> > }
> >
> > -uint16_t rte_vhost_poll_enqueue_completed(int vid, uint16_t queue_id,
> > +static __rte_always_inline uint16_t
> > +vhost_poll_enqueue_completed(struct virtio_net *dev, uint16_t
> > +queue_id,
> > struct rte_mbuf **pkts, uint16_t count) {
> > - struct virtio_net *dev = get_device(vid);
> > struct vhost_virtqueue *vq;
> > uint16_t n_pkts_cpl = 0, n_pkts_put = 0, n_descs = 0, n_buffers = 0;
> > uint16_t start_idx, pkts_idx, vq_size; @@ -2126,26 +2126,8 @@
> > uint16_t rte_vhost_poll_enqueue_completed(int vid, uint16_t queue_id,
> > uint16_t from, i;
> > int32_t n_poll;
> >
> > - if (!dev)
> > - return 0;
> > -
> > - VHOST_LOG_DATA(DEBUG, "(%d) %s\n", dev->vid, __func__);
> > - if (unlikely(!is_valid_virt_queue_idx(queue_id, 0, dev->nr_vring))) {
> > - VHOST_LOG_DATA(ERR, "(%d) %s: invalid virtqueue
> idx %d.\n",
> > - dev->vid, __func__, queue_id);
> > - return 0;
> > - }
> > -
> > vq = dev->virtqueue[queue_id];
> >
> > - if (unlikely(!vq->async_registered)) {
> > - VHOST_LOG_DATA(ERR, "(%d) %s: async not registered for
> queue
> > id %d.\n",
> > - dev->vid, __func__, queue_id);
> > - return 0;
> > - }
> > -
> > - rte_spinlock_lock(&vq->access_lock);
> > -
> > pkts_idx = vq->async_pkts_idx % vq->size;
> > pkts_info = vq->async_pkts_info;
> > vq_size = vq->size;
> > @@ -2153,7 +2135,7 @@ uint16_t rte_vhost_poll_enqueue_completed(int
> > vid, uint16_t queue_id,
> > vq_size, vq->async_pkts_inflight_n);
> >
> > if (count > vq->async_last_pkts_n) {
> > - n_poll = vq->async_ops.check_completed_copies(vid,
> > + n_poll = vq->async_ops.check_completed_copies(dev->vid,
> > queue_id, 0, count - vq->async_last_pkts_n);
> > if (n_poll >= 0) {
> > n_pkts_cpl = n_poll;
> > @@ -2168,7 +2150,7 @@ uint16_t rte_vhost_poll_enqueue_completed(int
> > vid, uint16_t queue_id,
> > n_pkts_put = RTE_MIN(count, n_pkts_cpl);
> > if (unlikely(n_pkts_put == 0)) {
> > vq->async_last_pkts_n = n_pkts_cpl;
> > - goto done;
> > + return 0;
> > }
> >
> > if (vq_is_packed(dev)) {
> > @@ -2207,12 +2189,74 @@ uint16_t
> rte_vhost_poll_enqueue_completed(int
> > vid, uint16_t queue_id,
> > vq->last_async_desc_idx_split += n_descs;
> > }
> >
> > -done:
> > + return n_pkts_put;
> > +}
> > +
> > +uint16_t rte_vhost_poll_enqueue_completed(int vid, uint16_t queue_id,
> > + struct rte_mbuf **pkts, uint16_t count)
>
> Based on DPDK coding style, things like return value should be in another
> new line.
>
> https://doc.dpdk.org/guides/contributing/coding_style.html#definitions
>
> For similar changes, please check.
>
> > +{
> > + struct virtio_net *dev = get_device(vid);
> > + struct vhost_virtqueue *vq;
> > + uint16_t n_pkts_put = 0;
>
> Since this val is for recording pkts completed, maybe n_pkts_cpl?
>
> > +
> > + if (!dev)
> > + return 0;
> > +
> > + VHOST_LOG_DATA(DEBUG, "(%d) %s\n", dev->vid, __func__);
> > + if (unlikely(!is_valid_virt_queue_idx(queue_id, 0, dev->nr_vring))) {
> > + VHOST_LOG_DATA(ERR, "(%d) %s: invalid virtqueue
> idx %d.\n",
> > + dev->vid, __func__, queue_id);
> > + return 0;
> > + }
> > +
> > + vq = dev->virtqueue[queue_id];
> > +
> > + if (unlikely(!vq->async_registered)) {
> > + VHOST_LOG_DATA(ERR, "(%d) %s: async not registered for
> queue
> > id %d.\n",
> > + dev->vid, __func__, queue_id);
> > + return 0;
> > + }
> > +
> > + rte_spinlock_lock(&vq->access_lock);
> > +
> > + n_pkts_put = vhost_poll_enqueue_completed(dev, queue_id, pkts,
> > +count);
> > +
> > rte_spinlock_unlock(&vq->access_lock);
> >
> > return n_pkts_put;
> > }
> >
> > +uint16_t rte_vhost_try_drain_queue_thread_unsafe(int vid, uint16_t
> queue_id,
> > + struct rte_mbuf **pkts, uint16_t count, uint16_t times) {
> > + struct virtio_net *dev = get_device(vid);
> > + struct vhost_virtqueue *vq;
> > + uint16_t n_cpl = 0;
>
> Make the name same as above
>
> > +
> > + if (!dev)
> > + return 0;
> > +
> > + VHOST_LOG_DATA(DEBUG, "(%d) %s\n", dev->vid, __func__);
> > + if (unlikely(!is_valid_virt_queue_idx(queue_id, 0, dev->nr_vring))) {
> > + VHOST_LOG_DATA(ERR, "(%d) %s: invalid virtqueue
> idx %d.\n",
> > + dev->vid, __func__, queue_id);
> > + return 0;
> > + }
> > +
> > + vq = dev->virtqueue[queue_id];
> > +
> > + if (unlikely(!vq->async_registered)) {
> > + VHOST_LOG_DATA(ERR, "(%d) %s: async not registered for
> queue
> > id %d.\n",
> > + dev->vid, __func__, queue_id);
> > + return 0;
> > + }
> > +
> > + while ((n_cpl < count) && times--)
>
> 'while (n_cpl < count && times--)' is enough
>
> Thanks,
> Chenbo
>
> > + n_cpl += vhost_poll_enqueue_completed(dev, queue_id,
> pkts + n_cpl,
> > count);
> > +
> > + return n_cpl;
> > +}
> > +
> > static __rte_always_inline uint32_t
> > virtio_dev_rx_async_submit(struct virtio_net *dev, uint16_t queue_id,
> > struct rte_mbuf **pkts, uint32_t count,
> > --
> > 2.29.2
