drivers/net/virtio/virtio_rxtx_simple_sse.c

   1 /*-
   2  *   BSD LICENSE
   3  *
   4  *   Copyright(c) 2010-2015 Intel Corporation. All rights reserved.
   5  *   All rights reserved.
   6  *
   7  *   Redistribution and use in source and binary forms, with or without
   8  *   modification, are permitted provided that the following conditions
   9  *   are met:
  10  *
  11  *     * Redistributions of source code must retain the above copyright
  12  *       notice, this list of conditions and the following disclaimer.
  13  *     * Redistributions in binary form must reproduce the above copyright
  14  *       notice, this list of conditions and the following disclaimer in
  15  *       the documentation and/or other materials provided with the
  16  *       distribution.
  17  *     * Neither the name of Intel Corporation nor the names of its
  18  *       contributors may be used to endorse or promote products derived
  19  *       from this software without specific prior written permission.
  20  *
  21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 #include <stdint.h>
  35 #include <stdio.h>
  36 #include <stdlib.h>
  37 #include <string.h>
  38 #include <errno.h>
  39
  40 #include <tmmintrin.h>
  41
  42 #include <rte_byteorder.h>
  43 #include <rte_branch_prediction.h>
  44 #include <rte_cycles.h>
  45 #include <rte_ether.h>
  46 #include <rte_ethdev.h>
  47 #include <rte_errno.h>
  48 #include <rte_memory.h>
  49 #include <rte_memzone.h>
  50 #include <rte_mempool.h>
  51 #include <rte_malloc.h>
  52 #include <rte_mbuf.h>
  53 #include <rte_prefetch.h>
  54 #include <rte_string_fns.h>
  55
  56 #include "virtio_rxtx_simple.h"
  57
  58 #define RTE_VIRTIO_VPMD_RX_BURST 32
  59 #define RTE_VIRTIO_DESC_PER_LOOP 8
  60 #define RTE_VIRTIO_VPMD_RX_REARM_THRESH RTE_VIRTIO_VPMD_RX_BURST
  61
  62 /* virtio vPMD receive routine, only accept(nb_pkts >= RTE_VIRTIO_DESC_PER_LOOP)
  63  *
  64  * This routine is for non-mergeable RX, one desc for each guest buffer.
  65  * This routine is based on the RX ring layout optimization. Each entry in the
  66  * avail ring points to the desc with the same index in the desc ring and this
  67  * will never be changed in the driver.
  68  *
  69  * - nb_pkts < RTE_VIRTIO_DESC_PER_LOOP, just return no packet
  70  */
  71 uint16_t
  72 virtio_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
  73         uint16_t nb_pkts)
  74 {
  75         struct virtnet_rx *rxvq = rx_queue;
  76         struct virtqueue *vq = rxvq->vq;
  77         struct virtio_hw *hw = vq->hw;
  78         uint16_t nb_used;
  79         uint16_t desc_idx;
  80         struct vring_used_elem *rused;
  81         struct rte_mbuf **sw_ring;
  82         struct rte_mbuf **sw_ring_end;
  83         uint16_t nb_pkts_received = 0;
  84         __m128i shuf_msk1, shuf_msk2, len_adjust;
  85
  86         shuf_msk1 = _mm_set_epi8(
  87                 0xFF, 0xFF, 0xFF, 0xFF,
  88                 0xFF, 0xFF,             /* vlan tci */
  89                 5, 4,                   /* dat len */
  90                 0xFF, 0xFF, 5, 4,       /* pkt len */
  91                 0xFF, 0xFF, 0xFF, 0xFF  /* packet type */
  92
  93         );
  94
  95         shuf_msk2 = _mm_set_epi8(
  96                 0xFF, 0xFF, 0xFF, 0xFF,
  97                 0xFF, 0xFF,             /* vlan tci */
  98                 13, 12,                 /* dat len */
  99                 0xFF, 0xFF, 13, 12,     /* pkt len */
 100                 0xFF, 0xFF, 0xFF, 0xFF  /* packet type */
 101         );
 102
 103         /* Subtract the header length.
 104         *  In which case do we need the header length in used->len ?
 105         */
 106         len_adjust = _mm_set_epi16(
 107                 0, 0,
 108                 0,
 109                 (uint16_t)-vq->hw->vtnet_hdr_size,
 110                 0, (uint16_t)-vq->hw->vtnet_hdr_size,
 111                 0, 0);
 112
 113         if (unlikely(hw->started == 0))
 114                 return nb_pkts_received;
 115
 116         if (unlikely(nb_pkts < RTE_VIRTIO_DESC_PER_LOOP))
 117                 return 0;
 118
 119         nb_used = VIRTQUEUE_NUSED(vq);
 120
 121         rte_compiler_barrier();
 122
 123         if (unlikely(nb_used == 0))
 124                 return 0;
 125
 126         nb_pkts = RTE_ALIGN_FLOOR(nb_pkts, RTE_VIRTIO_DESC_PER_LOOP);
 127         nb_used = RTE_MIN(nb_used, nb_pkts);
 128
 129         desc_idx = (uint16_t)(vq->vq_used_cons_idx & (vq->vq_nentries - 1));
 130         rused = &vq->vq_ring.used->ring[desc_idx];
 131         sw_ring  = &vq->sw_ring[desc_idx];
 132         sw_ring_end = &vq->sw_ring[vq->vq_nentries];
 133
 134         rte_prefetch0(rused);
 135
 136         if (vq->vq_free_cnt >= RTE_VIRTIO_VPMD_RX_REARM_THRESH) {
 137                 virtio_rxq_rearm_vec(rxvq);
 138                 if (unlikely(virtqueue_kick_prepare(vq)))
 139                         virtqueue_notify(vq);
 140         }
 141
 142         for (nb_pkts_received = 0;
 143                 nb_pkts_received < nb_used;) {
 144                 __m128i desc[RTE_VIRTIO_DESC_PER_LOOP / 2];
 145                 __m128i mbp[RTE_VIRTIO_DESC_PER_LOOP / 2];
 146                 __m128i pkt_mb[RTE_VIRTIO_DESC_PER_LOOP];
 147
 148                 mbp[0] = _mm_loadu_si128((__m128i *)(sw_ring + 0));
 149                 desc[0] = _mm_loadu_si128((__m128i *)(rused + 0));
 150                 _mm_storeu_si128((__m128i *)&rx_pkts[0], mbp[0]);
 151
 152                 mbp[1] = _mm_loadu_si128((__m128i *)(sw_ring + 2));
 153                 desc[1] = _mm_loadu_si128((__m128i *)(rused + 2));
 154                 _mm_storeu_si128((__m128i *)&rx_pkts[2], mbp[1]);
 155
 156                 mbp[2] = _mm_loadu_si128((__m128i *)(sw_ring + 4));
 157                 desc[2] = _mm_loadu_si128((__m128i *)(rused + 4));
 158                 _mm_storeu_si128((__m128i *)&rx_pkts[4], mbp[2]);
 159
 160                 mbp[3] = _mm_loadu_si128((__m128i *)(sw_ring + 6));
 161                 desc[3] = _mm_loadu_si128((__m128i *)(rused + 6));
 162                 _mm_storeu_si128((__m128i *)&rx_pkts[6], mbp[3]);
 163
 164                 pkt_mb[1] = _mm_shuffle_epi8(desc[0], shuf_msk2);
 165                 pkt_mb[0] = _mm_shuffle_epi8(desc[0], shuf_msk1);
 166                 pkt_mb[1] = _mm_add_epi16(pkt_mb[1], len_adjust);
 167                 pkt_mb[0] = _mm_add_epi16(pkt_mb[0], len_adjust);
 168                 _mm_storeu_si128((void *)&rx_pkts[1]->rx_descriptor_fields1,
 169                         pkt_mb[1]);
 170                 _mm_storeu_si128((void *)&rx_pkts[0]->rx_descriptor_fields1,
 171                         pkt_mb[0]);
 172
 173                 pkt_mb[3] = _mm_shuffle_epi8(desc[1], shuf_msk2);
 174                 pkt_mb[2] = _mm_shuffle_epi8(desc[1], shuf_msk1);
 175                 pkt_mb[3] = _mm_add_epi16(pkt_mb[3], len_adjust);
 176                 pkt_mb[2] = _mm_add_epi16(pkt_mb[2], len_adjust);
 177                 _mm_storeu_si128((void *)&rx_pkts[3]->rx_descriptor_fields1,
 178                         pkt_mb[3]);
 179                 _mm_storeu_si128((void *)&rx_pkts[2]->rx_descriptor_fields1,
 180                         pkt_mb[2]);
 181
 182                 pkt_mb[5] = _mm_shuffle_epi8(desc[2], shuf_msk2);
 183                 pkt_mb[4] = _mm_shuffle_epi8(desc[2], shuf_msk1);
 184                 pkt_mb[5] = _mm_add_epi16(pkt_mb[5], len_adjust);
 185                 pkt_mb[4] = _mm_add_epi16(pkt_mb[4], len_adjust);
 186                 _mm_storeu_si128((void *)&rx_pkts[5]->rx_descriptor_fields1,
 187                         pkt_mb[5]);
 188                 _mm_storeu_si128((void *)&rx_pkts[4]->rx_descriptor_fields1,
 189                         pkt_mb[4]);
 190
 191                 pkt_mb[7] = _mm_shuffle_epi8(desc[3], shuf_msk2);
 192                 pkt_mb[6] = _mm_shuffle_epi8(desc[3], shuf_msk1);
 193                 pkt_mb[7] = _mm_add_epi16(pkt_mb[7], len_adjust);
 194                 pkt_mb[6] = _mm_add_epi16(pkt_mb[6], len_adjust);
 195                 _mm_storeu_si128((void *)&rx_pkts[7]->rx_descriptor_fields1,
 196                         pkt_mb[7]);
 197                 _mm_storeu_si128((void *)&rx_pkts[6]->rx_descriptor_fields1,
 198                         pkt_mb[6]);
 199
 200                 if (unlikely(nb_used <= RTE_VIRTIO_DESC_PER_LOOP)) {
 201                         if (sw_ring + nb_used <= sw_ring_end)
 202                                 nb_pkts_received += nb_used;
 203                         else
 204                                 nb_pkts_received += sw_ring_end - sw_ring;
 205                         break;
 206                 } else {
 207                         if (unlikely(sw_ring + RTE_VIRTIO_DESC_PER_LOOP >=
 208                                 sw_ring_end)) {
 209                                 nb_pkts_received += sw_ring_end - sw_ring;
 210                                 break;
 211                         } else {
 212                                 nb_pkts_received += RTE_VIRTIO_DESC_PER_LOOP;
 213
 214                                 rx_pkts += RTE_VIRTIO_DESC_PER_LOOP;
 215                                 sw_ring += RTE_VIRTIO_DESC_PER_LOOP;
 216                                 rused   += RTE_VIRTIO_DESC_PER_LOOP;
 217                                 nb_used -= RTE_VIRTIO_DESC_PER_LOOP;
 218                         }
 219                 }
 220         }
 221
 222         vq->vq_used_cons_idx += nb_pkts_received;
 223         vq->vq_free_cnt += nb_pkts_received;
 224         rxvq->stats.packets += nb_pkts_received;
 225         return nb_pkts_received;
 226 }