d/numam-dpdk
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity
f4ed5a4a7c
numam-dpdk/drivers/net/virtio/virtio_rxtx_simple_neon.c
Thibaut Collet 016f56b5bc net/virtio: get all pending Rx packets in vectorized paths 
The loop to read packets does not take all packets as the number of
available packets (nb_used) is decremented in the loop.
Take all available packets provides a performance improvement of 3%.

Fixes: fc3d66212f ("virtio: add vector Rx")
Cc: stable@dpdk.org

Signed-off-by: Thibaut Collet <thibaut.collet@6wind.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-10-07 15:00:57 +02:00

215 lines
6.4 KiB
C
Raw Blame History

/* SPDX-License-Identifier: BSD-3-Clause
* Copyright(c) 2016 Cavium, Inc
*/
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <rte_byteorder.h>
#include <rte_branch_prediction.h>
#include <rte_cycles.h>
#include <rte_ether.h>
#include <rte_ethdev_driver.h>
#include <rte_errno.h>
#include <rte_memory.h>
#include <rte_mempool.h>
#include <rte_malloc.h>
#include <rte_mbuf.h>
#include <rte_prefetch.h>
#include <rte_string_fns.h>
#include <rte_vect.h>
#include "virtio_rxtx_simple.h"
#define RTE_VIRTIO_DESC_PER_LOOP 8
/* virtio vPMD receive routine, only accept(nb_pkts >= RTE_VIRTIO_DESC_PER_LOOP)
*
* This routine is for non-mergeable RX, one desc for each guest buffer.
* This routine is based on the RX ring layout optimization. Each entry in the
* avail ring points to the desc with the same index in the desc ring and this
* will never be changed in the driver.
*
* - nb_pkts < RTE_VIRTIO_DESC_PER_LOOP, just return no packet
*/
uint16_t
virtio_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
uint16_t nb_pkts)
{
struct virtnet_rx *rxvq = rx_queue;
struct virtqueue *vq = rxvq->vq;
struct virtio_hw *hw = vq->hw;
uint16_t nb_used, nb_total;
uint16_t desc_idx;
struct vring_used_elem *rused;
struct rte_mbuf **sw_ring;
struct rte_mbuf **sw_ring_end;
struct rte_mbuf **ref_rx_pkts;
uint16_t nb_pkts_received = 0;
uint8x16_t shuf_msk1 = {
0xFF, 0xFF, 0xFF, 0xFF, /* packet type */
4, 5, 0xFF, 0xFF, /* pkt len */
4, 5, /* dat len */
0xFF, 0xFF, /* vlan tci */
0xFF, 0xFF, 0xFF, 0xFF
};
uint8x16_t shuf_msk2 = {
0xFF, 0xFF, 0xFF, 0xFF, /* packet type */
12, 13, 0xFF, 0xFF, /* pkt len */
12, 13, /* dat len */
0xFF, 0xFF, /* vlan tci */
0xFF, 0xFF, 0xFF, 0xFF
};
/* Subtract the header length.
* In which case do we need the header length in used->len ?
*/
uint16x8_t len_adjust = {
0, 0,
(uint16_t)vq->hw->vtnet_hdr_size, 0,
(uint16_t)vq->hw->vtnet_hdr_size,
0,
0, 0
};
if (unlikely(hw->started == 0))
return nb_pkts_received;
if (unlikely(nb_pkts < RTE_VIRTIO_DESC_PER_LOOP))
return 0;
nb_used = VIRTQUEUE_NUSED(vq);
rte_rmb();
if (unlikely(nb_used == 0))
return 0;
nb_pkts = RTE_ALIGN_FLOOR(nb_pkts, RTE_VIRTIO_DESC_PER_LOOP);
nb_used = RTE_MIN(nb_used, nb_pkts);
desc_idx = (uint16_t)(vq->vq_used_cons_idx & (vq->vq_nentries - 1));
rused = &vq->vq_split.ring.used->ring[desc_idx];
sw_ring = &vq->sw_ring[desc_idx];
sw_ring_end = &vq->sw_ring[vq->vq_nentries];
rte_prefetch_non_temporal(rused);
if (vq->vq_free_cnt >= RTE_VIRTIO_VPMD_RX_REARM_THRESH) {
virtio_rxq_rearm_vec(rxvq);
if (unlikely(virtqueue_kick_prepare(vq)))
virtqueue_notify(vq);
}
nb_total = nb_used;
ref_rx_pkts = rx_pkts;
for (nb_pkts_received = 0;
nb_pkts_received < nb_total;) {
uint64x2_t desc[RTE_VIRTIO_DESC_PER_LOOP / 2];
uint64x2_t mbp[RTE_VIRTIO_DESC_PER_LOOP / 2];
uint64x2_t pkt_mb[RTE_VIRTIO_DESC_PER_LOOP];
mbp[0] = vld1q_u64((uint64_t *)(sw_ring + 0));
desc[0] = vld1q_u64((uint64_t *)(rused + 0));
vst1q_u64((uint64_t *)&rx_pkts[0], mbp[0]);
mbp[1] = vld1q_u64((uint64_t *)(sw_ring + 2));
desc[1] = vld1q_u64((uint64_t *)(rused + 2));
vst1q_u64((uint64_t *)&rx_pkts[2], mbp[1]);
mbp[2] = vld1q_u64((uint64_t *)(sw_ring + 4));
desc[2] = vld1q_u64((uint64_t *)(rused + 4));
vst1q_u64((uint64_t *)&rx_pkts[4], mbp[2]);
mbp[3] = vld1q_u64((uint64_t *)(sw_ring + 6));
desc[3] = vld1q_u64((uint64_t *)(rused + 6));
vst1q_u64((uint64_t *)&rx_pkts[6], mbp[3]);
pkt_mb[1] = vreinterpretq_u64_u8(vqtbl1q_u8(
vreinterpretq_u8_u64(desc[0]), shuf_msk2));
pkt_mb[0] = vreinterpretq_u64_u8(vqtbl1q_u8(
vreinterpretq_u8_u64(desc[0]), shuf_msk1));
pkt_mb[1] = vreinterpretq_u64_u16(vsubq_u16(
vreinterpretq_u16_u64(pkt_mb[1]), len_adjust));
pkt_mb[0] = vreinterpretq_u64_u16(vsubq_u16(
vreinterpretq_u16_u64(pkt_mb[0]), len_adjust));
vst1q_u64((void *)&rx_pkts[1]->rx_descriptor_fields1,
pkt_mb[1]);
vst1q_u64((void *)&rx_pkts[0]->rx_descriptor_fields1,
pkt_mb[0]);
pkt_mb[3] = vreinterpretq_u64_u8(vqtbl1q_u8(
vreinterpretq_u8_u64(desc[1]), shuf_msk2));
pkt_mb[2] = vreinterpretq_u64_u8(vqtbl1q_u8(
vreinterpretq_u8_u64(desc[1]), shuf_msk1));
pkt_mb[3] = vreinterpretq_u64_u16(vsubq_u16(
vreinterpretq_u16_u64(pkt_mb[3]), len_adjust));
pkt_mb[2] = vreinterpretq_u64_u16(vsubq_u16(
vreinterpretq_u16_u64(pkt_mb[2]), len_adjust));
vst1q_u64((void *)&rx_pkts[3]->rx_descriptor_fields1,
pkt_mb[3]);
vst1q_u64((void *)&rx_pkts[2]->rx_descriptor_fields1,
pkt_mb[2]);
pkt_mb[5] = vreinterpretq_u64_u8(vqtbl1q_u8(
vreinterpretq_u8_u64(desc[2]), shuf_msk2));
pkt_mb[4] = vreinterpretq_u64_u8(vqtbl1q_u8(
vreinterpretq_u8_u64(desc[2]), shuf_msk1));
pkt_mb[5] = vreinterpretq_u64_u16(vsubq_u16(
vreinterpretq_u16_u64(pkt_mb[5]), len_adjust));
pkt_mb[4] = vreinterpretq_u64_u16(vsubq_u16(
vreinterpretq_u16_u64(pkt_mb[4]), len_adjust));
vst1q_u64((void *)&rx_pkts[5]->rx_descriptor_fields1,
pkt_mb[5]);
vst1q_u64((void *)&rx_pkts[4]->rx_descriptor_fields1,
pkt_mb[4]);
pkt_mb[7] = vreinterpretq_u64_u8(vqtbl1q_u8(
vreinterpretq_u8_u64(desc[3]), shuf_msk2));
pkt_mb[6] = vreinterpretq_u64_u8(vqtbl1q_u8(
vreinterpretq_u8_u64(desc[3]), shuf_msk1));
pkt_mb[7] = vreinterpretq_u64_u16(vsubq_u16(
vreinterpretq_u16_u64(pkt_mb[7]), len_adjust));
pkt_mb[6] = vreinterpretq_u64_u16(vsubq_u16(
vreinterpretq_u16_u64(pkt_mb[6]), len_adjust));
vst1q_u64((void *)&rx_pkts[7]->rx_descriptor_fields1,
pkt_mb[7]);
vst1q_u64((void *)&rx_pkts[6]->rx_descriptor_fields1,
pkt_mb[6]);
if (unlikely(nb_used <= RTE_VIRTIO_DESC_PER_LOOP)) {
if (sw_ring + nb_used <= sw_ring_end)
nb_pkts_received += nb_used;
else
nb_pkts_received += sw_ring_end - sw_ring;
break;
} else {
if (unlikely(sw_ring + RTE_VIRTIO_DESC_PER_LOOP >=
sw_ring_end)) {
nb_pkts_received += sw_ring_end - sw_ring;
break;
} else {
nb_pkts_received += RTE_VIRTIO_DESC_PER_LOOP;
rx_pkts += RTE_VIRTIO_DESC_PER_LOOP;
sw_ring += RTE_VIRTIO_DESC_PER_LOOP;
rused += RTE_VIRTIO_DESC_PER_LOOP;
nb_used -= RTE_VIRTIO_DESC_PER_LOOP;
}
}
}
vq->vq_used_cons_idx += nb_pkts_received;
vq->vq_free_cnt += nb_pkts_received;
rxvq->stats.packets += nb_pkts_received;
for (nb_used = 0; nb_used < nb_pkts_received; nb_used++)
virtio_update_packet_stats(&rxvq->stats, ref_rx_pkts[nb_used]);
return nb_pkts_received;
}
Reference in New Issue View Git Blame Copy Permalink