From: Maxime Coquelin <maxime.coquelin@redhat.com>
To: xuan.ding@intel.com, chenbo.xia@intel.com
Cc: dev@dpdk.org, jiayu.hu@intel.com, cheng1.jiang@intel.com,
sunil.pai.g@intel.com, liangma@liangbit.com,
Yuan Wang <yuanx.wang@intel.com>
Subject: Re: [RFC,v3 1/2] vhost: support async dequeue for split ring
Date: Thu, 31 Mar 2022 11:15:12 +0200 [thread overview]
Message-ID: <38827506-7d29-9081-bb48-dbe01bd69b72@redhat.com> (raw)
In-Reply-To: <20220310065407.17145-2-xuan.ding@intel.com>
On 3/10/22 07:54, xuan.ding@intel.com wrote:
> From: Xuan Ding <xuan.ding@intel.com>
>
> This patch implements asynchronous dequeue data path for vhost split
> ring, with dmadev library integrated.
>
> Signed-off-by: Xuan Ding <xuan.ding@intel.com>
> Signed-off-by: Yuan Wang <yuanx.wang@intel.com>
> ---
> lib/vhost/rte_vhost_async.h | 37 ++-
> lib/vhost/version.map | 1 +
> lib/vhost/vhost.h | 1 +
> lib/vhost/virtio_net.c | 504 ++++++++++++++++++++++++++++++++++++
> 4 files changed, 541 insertions(+), 2 deletions(-)
>
> diff --git a/lib/vhost/rte_vhost_async.h b/lib/vhost/rte_vhost_async.h
> index f1293c6a9d..b6ab0b06a2 100644
> --- a/lib/vhost/rte_vhost_async.h
> +++ b/lib/vhost/rte_vhost_async.h
> @@ -155,9 +155,9 @@ int rte_vhost_async_get_inflight(int vid, uint16_t queue_id);
> * @param count
> * Size of the packet array
> * @param dma_id
> - * the identifier of DMA device
> + * The identifier of DMA device
> * @param vchan_id
> - * the identifier of virtual DMA channel
> + * The identifier of virtual DMA channel
This is unrelated to the purpose of this patch, it can be moved in a
dedicated trivial patch.
> * @return
> * Number of packets returned
> */
> @@ -187,6 +187,39 @@ uint16_t rte_vhost_clear_queue_thread_unsafe(int vid, uint16_t queue_id,
> __rte_experimental
> int rte_vhost_async_dma_configure(int16_t dma_id, uint16_t vchan_id);
>
> +/**
> + * This function tries to receive packets from the guest with offloading
> + * copies to the async channel. The packets that are transfer completed
> + * are returned in "pkts". The other packets that their copies are submitted to
> + * the async channel but not completed are called "in-flight packets".
> + * This function will not return in-flight packets until their copies are
> + * completed by the async channel.
> + *
> + * @param vid
> + * ID of vhost device to dequeue data
> + * @param queue_id
> + * ID of virtqueue to dequeue data
> + * @param mbuf_pool
> + * Mbuf_pool where host mbuf is allocated
> + * @param pkts
> + * Blank array to keep successfully dequeued packets
> + * @param count
> + * Size of the packet array
> + * @param nr_inflight
> + * The amount of in-flight packets. If error occurred, its value is set to -1.
> + * @param dma_id
> + * The identifier of DMA device
> + * @param vchan_id
> + * The identifier of virtual DMA channel
> + * @return
> + * Number of successfully dequeued packets
> + */
> +__rte_experimental
> +uint16_t
> +rte_vhost_async_try_dequeue_burst(int vid, uint16_t queue_id,
> + struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts, uint16_t count,
> + int *nr_inflight, uint16_t dma_id, uint16_t vchan_id);
> +
> #ifdef __cplusplus
> }
> #endif
> diff --git a/lib/vhost/version.map b/lib/vhost/version.map
> index 0a66c5840c..968d6d4290 100644
> --- a/lib/vhost/version.map
> +++ b/lib/vhost/version.map
> @@ -87,6 +87,7 @@ EXPERIMENTAL {
>
> # added in 22.03
> rte_vhost_async_dma_configure;
# added in 22.07
> + rte_vhost_async_try_dequeue_burst;
> };
>
> INTERNAL {
> diff --git a/lib/vhost/vhost.h b/lib/vhost/vhost.h
> index a9edc271aa..3799d41089 100644
> --- a/lib/vhost/vhost.h
> +++ b/lib/vhost/vhost.h
> @@ -178,6 +178,7 @@ extern struct async_dma_info dma_copy_track[RTE_DMADEV_DEFAULT_MAX];
> */
> struct async_inflight_info {
> struct rte_mbuf *mbuf;
> + struct virtio_net_hdr nethdr;
> uint16_t descs; /* num of descs inflight */
> uint16_t nr_buffers; /* num of buffers inflight for packed ring */
> };
> diff --git a/lib/vhost/virtio_net.c b/lib/vhost/virtio_net.c
> index 5f432b0d77..3816caca79 100644
> --- a/lib/vhost/virtio_net.c
> +++ b/lib/vhost/virtio_net.c
> @@ -3141,3 +3141,507 @@ rte_vhost_dequeue_burst(int vid, uint16_t queue_id,
>
> return count;
> }
> +
> +static __rte_always_inline int
> +async_desc_to_mbuf_seg(struct virtio_net *dev, struct vhost_virtqueue *vq,
> + struct rte_mbuf *m, uint32_t mbuf_offset,
> + uint64_t buf_iova, uint32_t cpy_len)
> +{
> + struct vhost_async *async = vq->async;
> + uint64_t mapped_len;
> + uint32_t buf_offset = 0;
> + void *host_iova;
> +
> + while (cpy_len) {
> + host_iova = (void *)(uintptr_t)gpa_to_first_hpa(dev,
> + buf_iova + buf_offset, cpy_len,
> + &mapped_len);
> + if (unlikely(!host_iova)) {
> + VHOST_LOG_DATA(ERR, "(%s) %s: failed to get host_iova.\n",
> + dev->ifname, __func__);
> + return -1;
> + }
> +
> + if (unlikely(async_iter_add_iovec(dev, async, host_iova,
> + (void *)(uintptr_t)rte_pktmbuf_iova_offset(m, mbuf_offset),
> + (size_t)mapped_len)))
> + return -1;
> +
> + cpy_len -= (uint32_t)mapped_len;
> + mbuf_offset += (uint32_t)mapped_len;
> + buf_offset += (uint32_t)mapped_len;
> + }
> +
> + return 0;
> +}
It looks really similar to async_mbuf_to_desc_seg(), just the direction
of the DMA copoy is changed.
Maybe we could refactor the two functions in a single one with adding a
parameter for the direction. Something like this:
static __rte_always_inline int
async_fill_seg(struct virtio_net *dev, struct vhost_virtqueue *vq,
struct rte_mbuf *m, uint32_t mbuf_offset,
uint64_t buf_iova, uint32_t cpy_len, bool to_desc)
{
struct vhost_async *async = vq->async;
uint64_t mapped_len;
uint32_t buf_offset = 0;
void *src, *dst
void *host_iova;
while (cpy_len) {
host_iova = (void *)(uintptr_t)gpa_to_first_hpa(dev,
buf_iova + buf_offset, cpy_len, &mapped_len);
if (unlikely(!host_iova)) {
VHOST_LOG_DATA(ERR, "(%s) %s: failed to get host iova.\n",
dev->ifname, __func__);
return -1;
}
if (to_desc) {
src = (void *)(uintptr_t)rte_pktmbuf_iova_offset(m, mbuff_offset);
dst = host_iova
} else {
dst = host_iova
src = (void *)(uintptr_t)rte_pktmbuf_iova_offset(m, mbuff_offset);
}
if (unlikely(async_iter_add_iovec(dev, async, src, dst,
(size_t)mapped_len)))
return -1;
cpy_len -= (uint32_t)mapped_len;
mbuf_offset += (uint32_t)mapped_len;
buf_offset += (uint32_t)mapped_len;
}
return 0;
}
Then if you don't pass a variable but a static true/false value for
to_desc, the compiler should generate the same code, so no performance
degradation.
> +
> +static __rte_always_inline int
> +async_desc_to_mbuf(struct virtio_net *dev, struct vhost_virtqueue *vq,
> + struct buf_vector *buf_vec, uint16_t nr_vec,
> + struct rte_mbuf *m, struct rte_mempool *mbuf_pool,
> + struct virtio_net_hdr *nethdr)
> +{
> + uint64_t buf_addr, buf_iova;
> + uint32_t buf_avail, buf_offset, buf_len;
> + uint32_t mbuf_avail, mbuf_offset;
> + uint32_t cpy_len;
> + /* A counter to avoid desc dead loop chain */
> + uint16_t vec_idx = 0;
> + struct rte_mbuf *cur = m, *prev = m;
> + struct virtio_net_hdr tmp_hdr;
> + struct virtio_net_hdr *hdr = NULL;
> + struct vhost_async *async = vq->async;
> +
> + buf_addr = buf_vec[vec_idx].buf_addr;
> + buf_len = buf_vec[vec_idx].buf_len;
> + buf_iova = buf_vec[vec_idx].buf_iova;
> +
> + if (unlikely(buf_len < dev->vhost_hlen && nr_vec <= 1))
> + return -1;
> +
> + if (virtio_net_with_host_offload(dev)) {
> + if (unlikely(buf_len < sizeof(struct virtio_net_hdr))) {
> + /*
> + * No luck, the virtio-net header doesn't fit
> + * in a contiguous virtual area.
> + */
> + copy_vnet_hdr_from_desc(&tmp_hdr, buf_vec);
> + hdr = &tmp_hdr;
> + } else {
> + hdr = (struct virtio_net_hdr *)((uintptr_t)buf_addr);
> + }
> + }
> +
> + /*
> + * A virtio driver normally uses at least 2 desc buffers
> + * for Tx: the first for storing the header, and others
> + * for storing the data.
> + */
> + if (unlikely(buf_len < dev->vhost_hlen)) {
> + buf_offset = dev->vhost_hlen - buf_len;
> + vec_idx++;
> + buf_addr = buf_vec[vec_idx].buf_addr;
> + buf_iova = buf_vec[vec_idx].buf_iova;
> + buf_len = buf_vec[vec_idx].buf_len;
> + buf_avail = buf_len - buf_offset;
> + } else if (buf_len == dev->vhost_hlen) {
> + if (unlikely(++vec_idx >= nr_vec))
> + return -1;
> + buf_addr = buf_vec[vec_idx].buf_addr;
> + buf_iova = buf_vec[vec_idx].buf_iova;
> + buf_len = buf_vec[vec_idx].buf_len;
> +
> + buf_offset = 0;
> + buf_avail = buf_len;
> + } else {
> + buf_offset = dev->vhost_hlen;
> + buf_avail = buf_vec[vec_idx].buf_len - dev->vhost_hlen;
> + }
> +
> + PRINT_PACKET(dev, (uintptr_t)(buf_addr + buf_offset), (uint32_t)buf_avail, 0);
> +
> + mbuf_offset = 0;
> + mbuf_avail = m->buf_len - RTE_PKTMBUF_HEADROOM;
> +
> + if (async_iter_initialize(dev, async))
> + return -1;
> +
> + while (1) {
> + cpy_len = RTE_MIN(buf_avail, mbuf_avail);
> +
> + if (async_desc_to_mbuf_seg(dev, vq, cur, mbuf_offset, buf_iova + buf_offset,
> + cpy_len) < 0)
> + goto error;
> +
> + mbuf_avail -= cpy_len;
> + buf_avail -= cpy_len;
> + mbuf_offset += cpy_len;
> + buf_offset += cpy_len;
> +
> + /* This buf reaches to its end, get the next one */
> + if (buf_avail == 0) {
> + if (++vec_idx >= nr_vec)
> + break;
> +
> + buf_addr = buf_vec[vec_idx].buf_addr;
> + buf_iova = buf_vec[vec_idx].buf_iova;
> + buf_len = buf_vec[vec_idx].buf_len;
> +
> + buf_offset = 0;
> + buf_avail = buf_len;
> +
> + PRINT_PACKET(dev, (uintptr_t)buf_addr, (uint32_t)buf_avail, 0);
> + }
> +
> + /*
> + * This mbuf reaches to its end, get a new one
> + * to hold more data.
> + */
> + if (mbuf_avail == 0) {
> + cur = rte_pktmbuf_alloc(mbuf_pool);
> + if (unlikely(cur == NULL)) {
> + VHOST_LOG_DATA(ERR,
> + "(%s) %s: failed to allocate memory for mbuf.\n",
> + dev->ifname, __func__);
> + goto error;
> + }
> +
> + prev->next = cur;
> + prev->data_len = mbuf_offset;
> + m->nb_segs += 1;
> + m->pkt_len += mbuf_offset;
> + prev = cur;
> +
> + mbuf_offset = 0;
> + mbuf_avail = cur->buf_len - RTE_PKTMBUF_HEADROOM;
> + }
> + }
> +
> + prev->data_len = mbuf_offset;
> + m->pkt_len += mbuf_offset;
> +
> + async_iter_finalize(async);
> + if (hdr)
> + *nethdr = *hdr;
> +
> + return 0;
> +
> +error:
> + async_iter_cancel(async);
> + return -1;
> +}
You can do here the same refactoring I did for the enqueue path, i.e.
merging copy_desc_to_mbuf and async_desc_to_mbuf in a single function.
> +static __rte_always_inline uint16_t
> +async_poll_dequeue_completed_split(struct virtio_net *dev, uint16_t queue_id,
> + struct rte_mbuf **pkts, uint16_t count, uint16_t dma_id,
> + uint16_t vchan_id, bool legacy_ol_flags)
> +{
> + uint16_t start_idx, from, i;
> + uint16_t nr_cpl_pkts = 0;
> + struct async_inflight_info *pkts_info;
> + struct vhost_virtqueue *vq = dev->virtqueue[queue_id];
> +
> + pkts_info = vq->async->pkts_info;
> +
> + vhost_async_dma_check_completed(dev, dma_id, vchan_id, VHOST_DMA_MAX_COPY_COMPLETE);
> +
> + start_idx = async_get_first_inflight_pkt_idx(vq);
> +
> + from = start_idx;
> + while (vq->async->pkts_cmpl_flag[from] && count--) {
> + vq->async->pkts_cmpl_flag[from] = false;
> + from = (from + 1) & (vq->size - 1);
> + nr_cpl_pkts++;
> + }
> +
> + if (nr_cpl_pkts == 0)
> + return 0;
> +
> + for (i = 0; i < nr_cpl_pkts; i++) {
> + from = (start_idx + i) & (vq->size - 1);
> + pkts[i] = pkts_info[from].mbuf;
> +
> + if (virtio_net_with_host_offload(dev))
> + vhost_dequeue_offload(dev, &pkts_info[from].nethdr, pkts[i],
> + legacy_ol_flags);
> + }
> +
> + /* write back completed descs to used ring and update used idx */
> + write_back_completed_descs_split(vq, nr_cpl_pkts);
> + __atomic_add_fetch(&vq->used->idx, nr_cpl_pkts, __ATOMIC_RELEASE);
> + vhost_vring_call_split(dev, vq);
> +
> + vq->async->pkts_inflight_n -= nr_cpl_pkts;
> +
> + return nr_cpl_pkts;
> +}
> +
> +static __rte_always_inline uint16_t
> +virtio_dev_tx_async_split(struct virtio_net *dev, struct vhost_virtqueue *vq,
> + uint16_t queue_id, struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts,
> + uint16_t count, uint16_t dma_id, uint16_t vchan_id, bool legacy_ol_flags)
> +{
> + static bool allocerr_warned;
> + bool dropped = false;
> + uint16_t free_entries;
> + uint16_t pkt_idx, slot_idx = 0;
> + uint16_t nr_done_pkts = 0;
> + uint16_t pkt_err = 0;
> + uint16_t n_xfer;
> + struct vhost_async *async = vq->async;
> + struct async_inflight_info *pkts_info = async->pkts_info;
> + struct rte_mbuf *pkts_prealloc[MAX_PKT_BURST];
> + uint16_t pkts_size = count;
> +
> + /**
> + * The ordering between avail index and
> + * desc reads needs to be enforced.
> + */
> + free_entries = __atomic_load_n(&vq->avail->idx, __ATOMIC_ACQUIRE) - vq->last_avail_idx;
> + if (free_entries == 0)
> + goto out;
> +
> + rte_prefetch0(&vq->avail->ring[vq->last_avail_idx & (vq->size - 1)]);
> +
> + async_iter_reset(async);
> +
> + count = RTE_MIN(count, MAX_PKT_BURST);
> + count = RTE_MIN(count, free_entries);
> + VHOST_LOG_DATA(DEBUG, "(%s) about to dequeue %u buffers\n", dev->ifname, count);
> +
> + if (rte_pktmbuf_alloc_bulk(mbuf_pool, pkts_prealloc, count))
> + goto out;
> +
> + for (pkt_idx = 0; pkt_idx < count; pkt_idx++) {
> + uint16_t head_idx = 0;
> + uint16_t nr_vec = 0;
> + uint16_t to;
> + uint32_t buf_len;
> + int err;
> + struct buf_vector buf_vec[BUF_VECTOR_MAX];
> + struct rte_mbuf *pkt = pkts_prealloc[pkt_idx];
> +
> + if (unlikely(fill_vec_buf_split(dev, vq, vq->last_avail_idx,
> + &nr_vec, buf_vec,
> + &head_idx, &buf_len,
> + VHOST_ACCESS_RO) < 0)) {
> + dropped = true;
> + break;
> + }
> +
> + err = virtio_dev_pktmbuf_prep(dev, pkt, buf_len);
> + if (unlikely(err)) {
> + /**
> + * mbuf allocation fails for jumbo packets when external
> + * buffer allocation is not allowed and linear buffer
> + * is required. Drop this packet.
> + */
> + if (!allocerr_warned) {
> + VHOST_LOG_DATA(ERR,
> + "(%s) %s: Failed mbuf alloc of size %d from %s\n",
> + dev->ifname, __func__, buf_len, mbuf_pool->name);
> + allocerr_warned = true;
> + }
> + dropped = true;
> + break;
> + }
> +
> + slot_idx = (async->pkts_idx + pkt_idx) & (vq->size - 1);
> + err = async_desc_to_mbuf(dev, vq, buf_vec, nr_vec, pkt, mbuf_pool,
> + &pkts_info[slot_idx].nethdr);
> + if (unlikely(err)) {
> + if (!allocerr_warned) {
> + VHOST_LOG_DATA(ERR,
> + "(%s) %s: Failed to offload copies to async channel.\n",
> + dev->ifname, __func__);
> + allocerr_warned = true;
> + }
> + dropped = true;
> + break;
> + }
> +
> + pkts_info[slot_idx].mbuf = pkt;
> +
> + /* store used descs */
> + to = async->desc_idx_split & (vq->size - 1);
> + async->descs_split[to].id = head_idx;
> + async->descs_split[to].len = 0;
> + async->desc_idx_split++;
> +
> + vq->last_avail_idx++;
> + }
> +
> + if (unlikely(dropped))
> + rte_pktmbuf_free_bulk(&pkts_prealloc[pkt_idx], count - pkt_idx);
> +
> + n_xfer = vhost_async_dma_transfer(dev, vq, dma_id, vchan_id, async->pkts_idx,
> + async->iov_iter, pkt_idx);
> +
> + async->pkts_inflight_n += n_xfer;
> +
> + pkt_err = pkt_idx - n_xfer;
> + if (unlikely(pkt_err)) {
> + VHOST_LOG_DATA(DEBUG,
> + "(%s) %s: failed to transfer data for queue id %d.\n",
> + dev->ifname, __func__, queue_id);
> +
> + pkt_idx = n_xfer;
> + /* recover available ring */
> + vq->last_avail_idx -= pkt_err;
> +
> + /**
> + * recover async channel copy related structures and free pktmbufs
> + * for error pkts.
> + */
> + async->desc_idx_split -= pkt_err;
> + while (pkt_err-- > 0) {
> + rte_pktmbuf_free(pkts_info[slot_idx & (vq->size - 1)].mbuf);
> + slot_idx--;
> + }
> + }
> +
> + async->pkts_idx += pkt_idx;
> + if (async->pkts_idx >= vq->size)
> + async->pkts_idx -= vq->size;
> +
> +out:
> + /* DMA device may serve other queues, unconditionally check completed. */
> + nr_done_pkts = async_poll_dequeue_completed_split(dev, queue_id, pkts, pkts_size,
> + dma_id, vchan_id, legacy_ol_flags);
> +
> + return nr_done_pkts;
> +}
> +
> +__rte_noinline
> +static uint16_t
> +virtio_dev_tx_async_split_legacy(struct virtio_net *dev,
> + struct vhost_virtqueue *vq, uint16_t queue_id,
> + struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts,
> + uint16_t count, uint16_t dma_id, uint16_t vchan_id)
> +{
> + return virtio_dev_tx_async_split(dev, vq, queue_id, mbuf_pool,
> + pkts, count, dma_id, vchan_id, true);
> +}
> +
> +__rte_noinline
> +static uint16_t
> +virtio_dev_tx_async_split_compliant(struct virtio_net *dev,
> + struct vhost_virtqueue *vq, uint16_t queue_id,
> + struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts,
> + uint16_t count, uint16_t dma_id, uint16_t vchan_id)
> +{
> + return virtio_dev_tx_async_split(dev, vq, queue_id, mbuf_pool,
> + pkts, count, dma_id, vchan_id, false);
> +}
> +
> +uint16_t
> +rte_vhost_async_try_dequeue_burst(int vid, uint16_t queue_id,
> + struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts, uint16_t count,
> + int *nr_inflight, uint16_t dma_id, uint16_t vchan_id)
> +{
> + struct virtio_net *dev;
> + struct rte_mbuf *rarp_mbuf = NULL;
> + struct vhost_virtqueue *vq;
> + int16_t success = 1;
> +
> + *nr_inflight = -1;
> +
> + dev = get_device(vid);
> + if (!dev)
> + return 0;
> +
> + if (unlikely(!(dev->flags & VIRTIO_DEV_BUILTIN_VIRTIO_NET))) {
> + VHOST_LOG_DATA(ERR,
> + "(%s) %s: built-in vhost net backend is disabled.\n",
> + dev->ifname, __func__);
> + return 0;
> + }
> +
> + if (unlikely(!is_valid_virt_queue_idx(queue_id, 1, dev->nr_vring))) {
> + VHOST_LOG_DATA(ERR,
> + "(%s) %s: invalid virtqueue idx %d.\n",
> + dev->ifname, __func__, queue_id);
> + return 0;
> + }
> +
> + if (unlikely(!dma_copy_track[dma_id].vchans ||
> + !dma_copy_track[dma_id].vchans[vchan_id].pkts_cmpl_flag_addr)) {
> + VHOST_LOG_DATA(ERR, "(%s) %s: invalid channel %d:%u.\n", dev->ifname, __func__,
> + dma_id, vchan_id);
> + return 0;
> + }
> +
> + vq = dev->virtqueue[queue_id];
> +
> + if (unlikely(rte_spinlock_trylock(&vq->access_lock) == 0))
> + return 0;
> +
> + if (unlikely(vq->enabled == 0)) {
> + count = 0;
> + goto out_access_unlock;
> + }
> +
> + if (unlikely(!vq->async)) {
> + VHOST_LOG_DATA(ERR, "(%s) %s: async not registered for queue id %d.\n",
> + dev->ifname, __func__, queue_id);
> + count = 0;
> + goto out_access_unlock;
> + }
> +
> + if (dev->features & (1ULL << VIRTIO_F_IOMMU_PLATFORM))
> + vhost_user_iotlb_rd_lock(vq);
> +
> + if (unlikely(vq->access_ok == 0))
> + if (unlikely(vring_translate(dev, vq) < 0)) {
> + count = 0;
> + goto out;
> + }
> +
> + /*
> + * Construct a RARP broadcast packet, and inject it to the "pkts"
> + * array, to looks like that guest actually send such packet.
> + *
> + * Check user_send_rarp() for more information.
> + *
> + * broadcast_rarp shares a cacheline in the virtio_net structure
> + * with some fields that are accessed during enqueue and
> + * __atomic_compare_exchange_n causes a write if performed compare
> + * and exchange. This could result in false sharing between enqueue
> + * and dequeue.
> + *
> + * Prevent unnecessary false sharing by reading broadcast_rarp first
> + * and only performing compare and exchange if the read indicates it
> + * is likely to be set.
> + */
> + if (unlikely(__atomic_load_n(&dev->broadcast_rarp, __ATOMIC_ACQUIRE) &&
> + __atomic_compare_exchange_n(&dev->broadcast_rarp,
> + &success, 0, 0, __ATOMIC_RELEASE, __ATOMIC_RELAXED))) {
> +
> + rarp_mbuf = rte_net_make_rarp_packet(mbuf_pool, &dev->mac);
> + if (rarp_mbuf == NULL) {
> + VHOST_LOG_DATA(ERR, "Failed to make RARP packet.\n");
> + count = 0;
> + goto out;
> + }
> + /*
> + * Inject it to the head of "pkts" array, so that switch's mac
> + * learning table will get updated first.
> + */
> + pkts[0] = rarp_mbuf;
> + pkts++;
> + count -= 1;
> + }
> +
> + if (unlikely(vq_is_packed(dev))) {
> + static bool not_support_pack_log;
> + if (!not_support_pack_log) {
> + VHOST_LOG_DATA(ERR,
> + "(%s) %s: async dequeue does not support packed ring.\n",
> + dev->ifname, __func__);
> + not_support_pack_log = true;
> + }
> + count = 0;
> + goto out;
> + }
> +
> + if (dev->flags & VIRTIO_DEV_LEGACY_OL_FLAGS)
> + count = virtio_dev_tx_async_split_legacy(dev, vq, queue_id,
> + mbuf_pool, pkts, count, dma_id, vchan_id);
> + else
> + count = virtio_dev_tx_async_split_compliant(dev, vq, queue_id,
> + mbuf_pool, pkts, count, dma_id, vchan_id);
> +
> + *nr_inflight = vq->async->pkts_inflight_n;
> +
> +out:
> + if (dev->features & (1ULL << VIRTIO_F_IOMMU_PLATFORM))
> + vhost_user_iotlb_rd_unlock(vq);
> +
> +out_access_unlock:
> + rte_spinlock_unlock(&vq->access_lock);
> +
> + if (unlikely(rarp_mbuf != NULL))
> + count += 1;
> +
> + return count;
> +}
next prev parent reply other threads:[~2022-03-31 9:15 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-01-01 0:12 [RFC 0/2] vhost: support async dequeue data path xuan.ding
2022-01-01 0:12 ` [RFC 1/2] vhost: support async dequeue for split ring xuan.ding
2022-01-01 0:12 ` [RFC 2/2] examples/vhost: support async dequeue data path xuan.ding
2022-02-24 11:03 ` [RFC,v2 0/2] vhost: " xuan.ding
2022-02-24 11:03 ` [RFC,v2 1/2] vhost: support async dequeue for split ring xuan.ding
2022-02-24 11:04 ` [RFC,v2 2/2] examples/vhost: support async dequeue data path xuan.ding
2022-03-10 6:54 ` [RFC,v3 0/2] vhost: " xuan.ding
2022-03-10 6:54 ` [RFC,v3 1/2] vhost: support async dequeue for split ring xuan.ding
2022-03-31 9:15 ` Maxime Coquelin [this message]
2022-03-31 11:20 ` Ding, Xuan
2022-03-10 6:54 ` [RFC,v3 2/2] examples/vhost: support async dequeue data path xuan.ding
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