[dpdk-dev] [PATCH v2 5/6] net/af_xdp: enable zero copy
Ye Xiaolong
xiaolong.ye at intel.com
Tue Mar 19 09:39:35 CET 2019
Hi, Mattias
Thanks for the review.
On 03/19, Mattias Rönnblom wrote:
>On 2019-03-19 08:12, Xiaolong Ye wrote:
>> Try to check if external mempool (from rx_queue_setup) is fit for
>> af_xdp, if it is, it will be registered to af_xdp socket directly and
>> there will be no packet data copy on Rx and Tx.
>>
>> Signed-off-by: Xiaolong Ye <xiaolong.ye at intel.com>
>> ---
>> drivers/net/af_xdp/rte_eth_af_xdp.c | 128 ++++++++++++++++++++--------
>> 1 file changed, 91 insertions(+), 37 deletions(-)
>>
>> diff --git a/drivers/net/af_xdp/rte_eth_af_xdp.c b/drivers/net/af_xdp/rte_eth_af_xdp.c
>> index fc60cb5c5..c22791e51 100644
>> --- a/drivers/net/af_xdp/rte_eth_af_xdp.c
>> +++ b/drivers/net/af_xdp/rte_eth_af_xdp.c
>> @@ -62,6 +62,7 @@ struct xsk_umem_info {
>> struct xsk_umem *umem;
>> struct rte_mempool *mb_pool;
>> void *buffer;
>> + uint8_t zc;
>> };
>> struct pkt_rx_queue {
>> @@ -76,6 +77,7 @@ struct pkt_rx_queue {
>> struct pkt_tx_queue *pair;
>> uint16_t queue_idx;
>> + uint8_t zc;
>> };
>> struct pkt_tx_queue {
>> @@ -191,17 +193,24 @@ eth_af_xdp_rx(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
>> uint32_t len = xsk_ring_cons__rx_desc(rx, idx_rx++)->len;
>> char *pkt = xsk_umem__get_data(rxq->umem->buffer, addr);
>> - mbuf = rte_pktmbuf_alloc(rxq->mb_pool);
>> - if (mbuf) {
>> - memcpy(rte_pktmbuf_mtod(mbuf, void*), pkt, len);
>> + if (rxq->zc) {
>> + mbuf = addr_to_mbuf(rxq->umem, addr);
>> rte_pktmbuf_pkt_len(mbuf) =
>> rte_pktmbuf_data_len(mbuf) = len;
>> - rx_bytes += len;
>> bufs[count++] = mbuf;
>> } else {
>> - dropped++;
>> + mbuf = rte_pktmbuf_alloc(rxq->mb_pool);
>> + if (mbuf) {
>
>if (likely(mbuf != NULL))
Got it.
>
>> + memcpy(rte_pktmbuf_mtod(mbuf, void*), pkt, len);
>
>Use rte_memcpy.
Got it.
>
>> + rte_pktmbuf_pkt_len(mbuf) =
>> + rte_pktmbuf_data_len(mbuf) = len;
>> + rx_bytes += len;
>> + bufs[count++] = mbuf;
>> + } else {
>> + dropped++;
>> + }
>> + rte_pktmbuf_free(addr_to_mbuf(umem, addr));
>> }
>> - rte_pktmbuf_free(addr_to_mbuf(umem, addr));
>> }
>> xsk_ring_cons__release(rx, rcvd);
>> @@ -285,22 +294,29 @@ eth_af_xdp_tx(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
>> - ETH_AF_XDP_DATA_HEADROOM;
>> desc = xsk_ring_prod__tx_desc(&txq->tx, idx_tx + i);
>> mbuf = bufs[i];
>> - if (mbuf->pkt_len <= buf_len) {
>> - mbuf_to_tx = rte_pktmbuf_alloc(umem->mb_pool);
>> - if (!mbuf_to_tx) {
>> - rte_pktmbuf_free(mbuf);
>> - continue;
>> - }
>> - desc->addr = mbuf_to_addr(umem, mbuf_to_tx);
>> + if (txq->pair->zc && mbuf->pool == umem->mb_pool) {
>> + desc->addr = mbuf_to_addr(umem, mbuf);
>> desc->len = mbuf->pkt_len;
>> - pkt = xsk_umem__get_data(umem->buffer,
>> - desc->addr);
>> - memcpy(pkt, rte_pktmbuf_mtod(mbuf, void *),
>> - desc->len);
>> valid++;
>> tx_bytes += mbuf->pkt_len;
>> + } else {
>> + if (mbuf->pkt_len <= buf_len) {
>> + mbuf_to_tx = rte_pktmbuf_alloc(umem->mb_pool);
>> + if (!mbuf_to_tx) {
>
>if (unlikely(mbuf_to_tx == NULL))
>
>See DPDK coding conventions 1.8.1 for how to do pointer comparisons.
I'll check it and do it correctly in next version.
>
>> + rte_pktmbuf_free(mbuf);
>> + continue;
>> + }
>> + desc->addr = mbuf_to_addr(umem, mbuf_to_tx);
>> + desc->len = mbuf->pkt_len;
>> + pkt = xsk_umem__get_data(umem->buffer,
>> + desc->addr);
>> + memcpy(pkt, rte_pktmbuf_mtod(mbuf, void *),
>> + desc->len);
>
>rte_memcpy()
Got it.
>
>> + valid++;
>> + tx_bytes += mbuf->pkt_len;
>> + }
>> + rte_pktmbuf_free(mbuf);
>> }
>> - rte_pktmbuf_free(mbuf);
>> }
>> xsk_ring_prod__submit(&txq->tx, nb_pkts);
>> @@ -479,7 +495,7 @@ static inline uint64_t get_len(struct rte_mempool *mp)
>> return (uint64_t)(memhdr->len);
>> }
>> -static struct xsk_umem_info *xdp_umem_configure(void)
>> +static struct xsk_umem_info *xdp_umem_configure(struct rte_mempool *mb_pool)
>> {
>> struct xsk_umem_info *umem;
>> struct xsk_umem_config usr_config = {
>> @@ -497,20 +513,25 @@ static struct xsk_umem_info *xdp_umem_configure(void)
>> return NULL;
>> }
>> - snprintf(pool_name, 0x100, "af_xdp_ring");
>> - umem->mb_pool = rte_pktmbuf_pool_create_with_flags(pool_name,
>> - ETH_AF_XDP_NUM_BUFFERS,
>> - 250, 0,
>> - ETH_AF_XDP_FRAME_SIZE -
>> - ETH_AF_XDP_MBUF_OVERHEAD,
>> - MEMPOOL_F_NO_SPREAD | MEMPOOL_F_PAGE_ALIGN,
>> - SOCKET_ID_ANY);
>> -
>> - if (!umem->mb_pool || umem->mb_pool->nb_mem_chunks != 1) {
>> - RTE_LOG(ERR, AF_XDP,
>> - "Failed to create rte_mempool\n");
>> - goto err;
>> + if (!mb_pool) {
>
>1.8.1
Got it.
>
>> + snprintf(pool_name, 0x100, "af_xdp_ring");
>
>0x100??
Will use RTE_MEMPOOL_NAMESIZE instead.
>
>> + umem->mb_pool = rte_pktmbuf_pool_create_with_flags(pool_name,
>> + ETH_AF_XDP_NUM_BUFFERS,
>> + 250, 0,
>> + ETH_AF_XDP_FRAME_SIZE -
>> + ETH_AF_XDP_MBUF_OVERHEAD,
>> + MEMPOOL_F_NO_SPREAD | MEMPOOL_F_PAGE_ALIGN,
>> + SOCKET_ID_ANY);
>> +
>> + if (!umem->mb_pool || umem->mb_pool->nb_mem_chunks != 1) {
>
>1.8.1
Got it.
>
>> + RTE_LOG(ERR, AF_XDP, "Failed to create rte_mempool\n");
>> + goto err;
>> + }
>> + } else {
>> + umem->mb_pool = mb_pool;
>> + umem->zc = 1;
>> }
>> +
>> base_addr = (void *)get_base_addr(umem->mb_pool);
>> ret = xsk_umem__create(&umem->umem, base_addr,
>> @@ -531,16 +552,43 @@ static struct xsk_umem_info *xdp_umem_configure(void)
>> return NULL;
>> }
>> +static uint8_t
>> +check_mempool_zc(struct rte_mempool *mp)
>> +{
>> + RTE_ASSERT(mp);
>> +
>> + /* must continues */
>> + if (mp->nb_mem_chunks > 1)
>> + return 0;
>> +
>> + /* check header size */
>> + if (mp->header_size != RTE_CACHE_LINE_SIZE)
>> + return 0;
>> +
>> + /* check base address */
>> + if ((uint64_t)get_base_addr(mp) % getpagesize() != 0)
>
>This should be an uintptr_t cast.
Got it.
Thanks,
Xiaolong
>
>> + return 0;
>> +
>> + /* check chunk size */
>> + if ((mp->elt_size + mp->header_size + mp->trailer_size) %
>> + ETH_AF_XDP_FRAME_SIZE != 0)
>> + return 0;
>> +
>> + return 1;
>> +}
>> +
>> static int
>> xsk_configure(struct pmd_internals *internals, struct pkt_rx_queue *rxq,
>> - int ring_size)
>> + int ring_size, struct rte_mempool *mb_pool)
>> {
>> struct xsk_socket_config cfg;
>> struct pkt_tx_queue *txq = rxq->pair;
>> + struct rte_mempool *mp;
>> int ret = 0;
>> int reserve_size;
>> - rxq->umem = xdp_umem_configure();
>> + mp = check_mempool_zc(mb_pool) ? mb_pool : NULL;
>> + rxq->umem = xdp_umem_configure(mp);
>> if (!rxq->umem) {
>> ret = -ENOMEM;
>> goto err;
>> @@ -627,15 +675,21 @@ eth_rx_queue_setup(struct rte_eth_dev *dev,
>> rxq->mb_pool = mb_pool;
>> - if (xsk_configure(internals, rxq, nb_rx_desc)) {
>> - RTE_LOG(ERR, AF_XDP,
>> - "Failed to configure xdp socket\n");
>> + if (xsk_configure(internals, rxq, nb_rx_desc, mb_pool)) {
>> + RTE_LOG(ERR, AF_XDP, "Failed to configure xdp socket\n");
>> ret = -EINVAL;
>> goto err;
>> }
>> internals->umem = rxq->umem;
>> + if (mb_pool == internals->umem->mb_pool)
>> + rxq->zc = internals->umem->zc;
>> +
>> + if (rxq->zc)
>> + RTE_LOG(INFO, AF_XDP,
>> + "zero copy enabled on rx queue %d\n", rx_queue_id);
>> +
>> dev->data->rx_queues[rx_queue_id] = rxq;
>> return 0;
>>
More information about the dev
mailing list