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 <rte_vect.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 <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
virtio_recv_pkts_vec(void * rx_queue,struct rte_mbuf ** rx_pkts,uint16_t nb_pkts)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 = virtnet_rxq_to_vq(rxvq);
45 struct virtio_hw *hw = vq->hw;
46 uint16_t nb_used, nb_total;
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 struct rte_mbuf **ref_rx_pkts;
52 uint16_t nb_pkts_received = 0;
53 __m128i shuf_msk1, shuf_msk2, len_adjust;
54
55 shuf_msk1 = _mm_set_epi8(
56 0xFF, 0xFF, 0xFF, 0xFF,
57 0xFF, 0xFF, /* vlan tci */
58 5, 4, /* dat len */
59 0xFF, 0xFF, 5, 4, /* pkt len */
60 0xFF, 0xFF, 0xFF, 0xFF /* packet type */
61
62 );
63
64 shuf_msk2 = _mm_set_epi8(
65 0xFF, 0xFF, 0xFF, 0xFF,
66 0xFF, 0xFF, /* vlan tci */
67 13, 12, /* dat len */
68 0xFF, 0xFF, 13, 12, /* pkt len */
69 0xFF, 0xFF, 0xFF, 0xFF /* packet type */
70 );
71
72 /* Subtract the header length.
73 * In which case do we need the header length in used->len ?
74 */
75 len_adjust = _mm_set_epi16(
76 0, 0,
77 0,
78 (uint16_t)-vq->hw->vtnet_hdr_size,
79 0, (uint16_t)-vq->hw->vtnet_hdr_size,
80 0, 0);
81
82 if (unlikely(hw->started == 0))
83 return nb_pkts_received;
84
85 if (unlikely(nb_pkts < RTE_VIRTIO_DESC_PER_LOOP))
86 return 0;
87
88 if (vq->vq_free_cnt >= RTE_VIRTIO_VPMD_RX_REARM_THRESH) {
89 virtio_rxq_rearm_vec(rxvq);
90 if (unlikely(virtqueue_kick_prepare(vq)))
91 virtqueue_notify(vq);
92 }
93
94 nb_used = virtqueue_nused(vq);
95
96 if (unlikely(nb_used == 0))
97 return 0;
98
99 nb_pkts = RTE_ALIGN_FLOOR(nb_pkts, RTE_VIRTIO_DESC_PER_LOOP);
100 nb_used = RTE_MIN(nb_used, nb_pkts);
101
102 desc_idx = (uint16_t)(vq->vq_used_cons_idx & (vq->vq_nentries - 1));
103 rused = &vq->vq_split.ring.used->ring[desc_idx];
104 sw_ring = &vq->rxq.sw_ring[desc_idx];
105 sw_ring_end = &vq->rxq.sw_ring[vq->vq_nentries];
106
107 rte_prefetch0(rused);
108
109 nb_total = nb_used;
110 ref_rx_pkts = rx_pkts;
111 for (nb_pkts_received = 0;
112 nb_pkts_received < nb_total;) {
113 __m128i desc[RTE_VIRTIO_DESC_PER_LOOP / 2];
114 __m128i mbp[RTE_VIRTIO_DESC_PER_LOOP / 2];
115 __m128i pkt_mb[RTE_VIRTIO_DESC_PER_LOOP];
116
117 mbp[0] = _mm_loadu_si128((__m128i *)(sw_ring + 0));
118 desc[0] = _mm_loadu_si128((__m128i *)(rused + 0));
119 _mm_storeu_si128((__m128i *)&rx_pkts[0], mbp[0]);
120
121 mbp[1] = _mm_loadu_si128((__m128i *)(sw_ring + 2));
122 desc[1] = _mm_loadu_si128((__m128i *)(rused + 2));
123 _mm_storeu_si128((__m128i *)&rx_pkts[2], mbp[1]);
124
125 mbp[2] = _mm_loadu_si128((__m128i *)(sw_ring + 4));
126 desc[2] = _mm_loadu_si128((__m128i *)(rused + 4));
127 _mm_storeu_si128((__m128i *)&rx_pkts[4], mbp[2]);
128
129 mbp[3] = _mm_loadu_si128((__m128i *)(sw_ring + 6));
130 desc[3] = _mm_loadu_si128((__m128i *)(rused + 6));
131 _mm_storeu_si128((__m128i *)&rx_pkts[6], mbp[3]);
132
133 pkt_mb[1] = _mm_shuffle_epi8(desc[0], shuf_msk2);
134 pkt_mb[0] = _mm_shuffle_epi8(desc[0], shuf_msk1);
135 pkt_mb[1] = _mm_add_epi16(pkt_mb[1], len_adjust);
136 pkt_mb[0] = _mm_add_epi16(pkt_mb[0], len_adjust);
137 _mm_storeu_si128((void *)&rx_pkts[1]->rx_descriptor_fields1,
138 pkt_mb[1]);
139 _mm_storeu_si128((void *)&rx_pkts[0]->rx_descriptor_fields1,
140 pkt_mb[0]);
141
142 pkt_mb[3] = _mm_shuffle_epi8(desc[1], shuf_msk2);
143 pkt_mb[2] = _mm_shuffle_epi8(desc[1], shuf_msk1);
144 pkt_mb[3] = _mm_add_epi16(pkt_mb[3], len_adjust);
145 pkt_mb[2] = _mm_add_epi16(pkt_mb[2], len_adjust);
146 _mm_storeu_si128((void *)&rx_pkts[3]->rx_descriptor_fields1,
147 pkt_mb[3]);
148 _mm_storeu_si128((void *)&rx_pkts[2]->rx_descriptor_fields1,
149 pkt_mb[2]);
150
151 pkt_mb[5] = _mm_shuffle_epi8(desc[2], shuf_msk2);
152 pkt_mb[4] = _mm_shuffle_epi8(desc[2], shuf_msk1);
153 pkt_mb[5] = _mm_add_epi16(pkt_mb[5], len_adjust);
154 pkt_mb[4] = _mm_add_epi16(pkt_mb[4], len_adjust);
155 _mm_storeu_si128((void *)&rx_pkts[5]->rx_descriptor_fields1,
156 pkt_mb[5]);
157 _mm_storeu_si128((void *)&rx_pkts[4]->rx_descriptor_fields1,
158 pkt_mb[4]);
159
160 pkt_mb[7] = _mm_shuffle_epi8(desc[3], shuf_msk2);
161 pkt_mb[6] = _mm_shuffle_epi8(desc[3], shuf_msk1);
162 pkt_mb[7] = _mm_add_epi16(pkt_mb[7], len_adjust);
163 pkt_mb[6] = _mm_add_epi16(pkt_mb[6], len_adjust);
164 _mm_storeu_si128((void *)&rx_pkts[7]->rx_descriptor_fields1,
165 pkt_mb[7]);
166 _mm_storeu_si128((void *)&rx_pkts[6]->rx_descriptor_fields1,
167 pkt_mb[6]);
168
169 if (unlikely(nb_used <= RTE_VIRTIO_DESC_PER_LOOP)) {
170 if (sw_ring + nb_used <= sw_ring_end)
171 nb_pkts_received += nb_used;
172 else
173 nb_pkts_received += sw_ring_end - sw_ring;
174 break;
175 } else {
176 if (unlikely(sw_ring + RTE_VIRTIO_DESC_PER_LOOP >=
177 sw_ring_end)) {
178 nb_pkts_received += sw_ring_end - sw_ring;
179 break;
180 } else {
181 nb_pkts_received += RTE_VIRTIO_DESC_PER_LOOP;
182
183 rx_pkts += RTE_VIRTIO_DESC_PER_LOOP;
184 sw_ring += RTE_VIRTIO_DESC_PER_LOOP;
185 rused += RTE_VIRTIO_DESC_PER_LOOP;
186 nb_used -= RTE_VIRTIO_DESC_PER_LOOP;
187 }
188 }
189 }
190
191 vq->vq_used_cons_idx += nb_pkts_received;
192 vq->vq_free_cnt += nb_pkts_received;
193 rxvq->stats.packets += nb_pkts_received;
194 for (nb_used = 0; nb_used < nb_pkts_received; nb_used++)
195 virtio_update_packet_stats(&rxvq->stats, ref_rx_pkts[nb_used]);
196
197 return nb_pkts_received;
198 }
199