drivers/net/virtio/virtio_rxtx_simple_sse.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2010-2015 Intel Corporation
   3  */
   4
   5 #include <stdint.h>
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <string.h>
   9 #include <errno.h>
  10
  11 #include <tmmintrin.h>
  12
  13 #include <rte_byteorder.h>
  14 #include <rte_branch_prediction.h>
  15 #include <rte_cycles.h>
  16 #include <rte_ether.h>
  17 #include <rte_ethdev_driver.h>
  18 #include <rte_errno.h>
  19 #include <rte_memory.h>
  20 #include <rte_mempool.h>
  21 #include <rte_malloc.h>
  22 #include <rte_mbuf.h>
  23 #include <rte_prefetch.h>
  24 #include <rte_string_fns.h>
  25
  26 #include "virtio_rxtx_simple.h"
  27
  28 #define RTE_VIRTIO_DESC_PER_LOOP 8
  29
  30 /* virtio vPMD receive routine, only accept(nb_pkts >= RTE_VIRTIO_DESC_PER_LOOP)
  31  *
  32  * This routine is for non-mergeable RX, one desc for each guest buffer.
  33  * This routine is based on the RX ring layout optimization. Each entry in the
  34  * avail ring points to the desc with the same index in the desc ring and this
  35  * will never be changed in the driver.
  36  *
  37  * - nb_pkts < RTE_VIRTIO_DESC_PER_LOOP, just return no packet
  38  */
  39 uint16_t
  40 virtio_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
  41         uint16_t nb_pkts)
  42 {
  43         struct virtnet_rx *rxvq = rx_queue;
  44         struct virtqueue *vq = rxvq->vq;
  45         struct virtio_hw *hw = vq->hw;
  46         uint16_t nb_used;
  47         uint16_t desc_idx;
  48         struct vring_used_elem *rused;
  49         struct rte_mbuf **sw_ring;
  50         struct rte_mbuf **sw_ring_end;
  51         uint16_t nb_pkts_received = 0;
  52         __m128i shuf_msk1, shuf_msk2, len_adjust;
  53
  54         shuf_msk1 = _mm_set_epi8(
  55                 0xFF, 0xFF, 0xFF, 0xFF,
  56                 0xFF, 0xFF,             /* vlan tci */
  57                 5, 4,                   /* dat len */
  58                 0xFF, 0xFF, 5, 4,       /* pkt len */
  59                 0xFF, 0xFF, 0xFF, 0xFF  /* packet type */
  60
  61         );
  62
  63         shuf_msk2 = _mm_set_epi8(
  64                 0xFF, 0xFF, 0xFF, 0xFF,
  65                 0xFF, 0xFF,             /* vlan tci */
  66                 13, 12,                 /* dat len */
  67                 0xFF, 0xFF, 13, 12,     /* pkt len */
  68                 0xFF, 0xFF, 0xFF, 0xFF  /* packet type */
  69         );
  70
  71         /* Subtract the header length.
  72         *  In which case do we need the header length in used->len ?
  73         */
  74         len_adjust = _mm_set_epi16(
  75                 0, 0,
  76                 0,
  77                 (uint16_t)-vq->hw->vtnet_hdr_size,
  78                 0, (uint16_t)-vq->hw->vtnet_hdr_size,
  79                 0, 0);
  80
  81         if (unlikely(hw->started == 0))
  82                 return nb_pkts_received;
  83
  84         if (unlikely(nb_pkts < RTE_VIRTIO_DESC_PER_LOOP))
  85                 return 0;
  86
  87         nb_used = VIRTQUEUE_NUSED(vq);
  88
  89         rte_compiler_barrier();
  90
  91         if (unlikely(nb_used == 0))
  92                 return 0;
  93
  94         nb_pkts = RTE_ALIGN_FLOOR(nb_pkts, RTE_VIRTIO_DESC_PER_LOOP);
  95         nb_used = RTE_MIN(nb_used, nb_pkts);
  96
  97         desc_idx = (uint16_t)(vq->vq_used_cons_idx & (vq->vq_nentries - 1));
  98         rused = &vq->vq_ring.used->ring[desc_idx];
  99         sw_ring  = &vq->sw_ring[desc_idx];
 100         sw_ring_end = &vq->sw_ring[vq->vq_nentries];
 101
 102         rte_prefetch0(rused);
 103
 104         if (vq->vq_free_cnt >= RTE_VIRTIO_VPMD_RX_REARM_THRESH) {
 105                 virtio_rxq_rearm_vec(rxvq);
 106                 if (unlikely(virtqueue_kick_prepare(vq)))
 107                         virtqueue_notify(vq);
 108         }
 109
 110         for (nb_pkts_received = 0;
 111                 nb_pkts_received < nb_used;) {
 112                 __m128i desc[RTE_VIRTIO_DESC_PER_LOOP / 2];
 113                 __m128i mbp[RTE_VIRTIO_DESC_PER_LOOP / 2];
 114                 __m128i pkt_mb[RTE_VIRTIO_DESC_PER_LOOP];
 115
 116                 mbp[0] = _mm_loadu_si128((__m128i *)(sw_ring + 0));
 117                 desc[0] = _mm_loadu_si128((__m128i *)(rused + 0));
 118                 _mm_storeu_si128((__m128i *)&rx_pkts[0], mbp[0]);
 119
 120                 mbp[1] = _mm_loadu_si128((__m128i *)(sw_ring + 2));
 121                 desc[1] = _mm_loadu_si128((__m128i *)(rused + 2));
 122                 _mm_storeu_si128((__m128i *)&rx_pkts[2], mbp[1]);
 123
 124                 mbp[2] = _mm_loadu_si128((__m128i *)(sw_ring + 4));
 125                 desc[2] = _mm_loadu_si128((__m128i *)(rused + 4));
 126                 _mm_storeu_si128((__m128i *)&rx_pkts[4], mbp[2]);
 127
 128                 mbp[3] = _mm_loadu_si128((__m128i *)(sw_ring + 6));
 129                 desc[3] = _mm_loadu_si128((__m128i *)(rused + 6));
 130                 _mm_storeu_si128((__m128i *)&rx_pkts[6], mbp[3]);
 131
 132                 pkt_mb[1] = _mm_shuffle_epi8(desc[0], shuf_msk2);
 133                 pkt_mb[0] = _mm_shuffle_epi8(desc[0], shuf_msk1);
 134                 pkt_mb[1] = _mm_add_epi16(pkt_mb[1], len_adjust);
 135                 pkt_mb[0] = _mm_add_epi16(pkt_mb[0], len_adjust);
 136                 _mm_storeu_si128((void *)&rx_pkts[1]->rx_descriptor_fields1,
 137                         pkt_mb[1]);
 138                 _mm_storeu_si128((void *)&rx_pkts[0]->rx_descriptor_fields1,
 139                         pkt_mb[0]);
 140
 141                 pkt_mb[3] = _mm_shuffle_epi8(desc[1], shuf_msk2);
 142                 pkt_mb[2] = _mm_shuffle_epi8(desc[1], shuf_msk1);
 143                 pkt_mb[3] = _mm_add_epi16(pkt_mb[3], len_adjust);
 144                 pkt_mb[2] = _mm_add_epi16(pkt_mb[2], len_adjust);
 145                 _mm_storeu_si128((void *)&rx_pkts[3]->rx_descriptor_fields1,
 146                         pkt_mb[3]);
 147                 _mm_storeu_si128((void *)&rx_pkts[2]->rx_descriptor_fields1,
 148                         pkt_mb[2]);
 149
 150                 pkt_mb[5] = _mm_shuffle_epi8(desc[2], shuf_msk2);
 151                 pkt_mb[4] = _mm_shuffle_epi8(desc[2], shuf_msk1);
 152                 pkt_mb[5] = _mm_add_epi16(pkt_mb[5], len_adjust);
 153                 pkt_mb[4] = _mm_add_epi16(pkt_mb[4], len_adjust);
 154                 _mm_storeu_si128((void *)&rx_pkts[5]->rx_descriptor_fields1,
 155                         pkt_mb[5]);
 156                 _mm_storeu_si128((void *)&rx_pkts[4]->rx_descriptor_fields1,
 157                         pkt_mb[4]);
 158
 159                 pkt_mb[7] = _mm_shuffle_epi8(desc[3], shuf_msk2);
 160                 pkt_mb[6] = _mm_shuffle_epi8(desc[3], shuf_msk1);
 161                 pkt_mb[7] = _mm_add_epi16(pkt_mb[7], len_adjust);
 162                 pkt_mb[6] = _mm_add_epi16(pkt_mb[6], len_adjust);
 163                 _mm_storeu_si128((void *)&rx_pkts[7]->rx_descriptor_fields1,
 164                         pkt_mb[7]);
 165                 _mm_storeu_si128((void *)&rx_pkts[6]->rx_descriptor_fields1,
 166                         pkt_mb[6]);
 167
 168                 if (unlikely(nb_used <= RTE_VIRTIO_DESC_PER_LOOP)) {
 169                         if (sw_ring + nb_used <= sw_ring_end)
 170                                 nb_pkts_received += nb_used;
 171                         else
 172                                 nb_pkts_received += sw_ring_end - sw_ring;
 173                         break;
 174                 } else {
 175                         if (unlikely(sw_ring + RTE_VIRTIO_DESC_PER_LOOP >=
 176                                 sw_ring_end)) {
 177                                 nb_pkts_received += sw_ring_end - sw_ring;
 178                                 break;
 179                         } else {
 180                                 nb_pkts_received += RTE_VIRTIO_DESC_PER_LOOP;
 181
 182                                 rx_pkts += RTE_VIRTIO_DESC_PER_LOOP;
 183                                 sw_ring += RTE_VIRTIO_DESC_PER_LOOP;
 184                                 rused   += RTE_VIRTIO_DESC_PER_LOOP;
 185                                 nb_used -= RTE_VIRTIO_DESC_PER_LOOP;
 186                         }
 187                 }
 188         }
 189
 190         vq->vq_used_cons_idx += nb_pkts_received;
 191         vq->vq_free_cnt += nb_pkts_received;
 192         rxvq->stats.packets += nb_pkts_received;
 193         return nb_pkts_received;
 194 }