ceph/src/seastar/dpdk/examples/l3fwd/l3fwd_neon.h

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2016-2018 Intel Corporation.
   3  * Copyright(c) 2017-2018 Linaro Limited.
   4  */
   5
   6 #ifndef _L3FWD_NEON_H_
   7 #define _L3FWD_NEON_H_
   8
   9 #include "l3fwd.h"
  10 #include "l3fwd_common.h"
  11
  12 /*
  13  * Update source and destination MAC addresses in the ethernet header.
  14  * Perform RFC1812 checks and updates for IPV4 packets.
  15  */
  16 static inline void
  17 processx4_step3(struct rte_mbuf *pkt[FWDSTEP], uint16_t dst_port[FWDSTEP])
  18 {
  19         uint32x4_t te[FWDSTEP];
  20         uint32x4_t ve[FWDSTEP];
  21         uint32_t *p[FWDSTEP];
  22
  23         p[0] = rte_pktmbuf_mtod(pkt[0], uint32_t *);
  24         p[1] = rte_pktmbuf_mtod(pkt[1], uint32_t *);
  25         p[2] = rte_pktmbuf_mtod(pkt[2], uint32_t *);
  26         p[3] = rte_pktmbuf_mtod(pkt[3], uint32_t *);
  27
  28         ve[0] = vreinterpretq_u32_s32(val_eth[dst_port[0]]);
  29         te[0] = vld1q_u32(p[0]);
  30
  31         ve[1] = vreinterpretq_u32_s32(val_eth[dst_port[1]]);
  32         te[1] = vld1q_u32(p[1]);
  33
  34         ve[2] = vreinterpretq_u32_s32(val_eth[dst_port[2]]);
  35         te[2] = vld1q_u32(p[2]);
  36
  37         ve[3] = vreinterpretq_u32_s32(val_eth[dst_port[3]]);
  38         te[3] = vld1q_u32(p[3]);
  39
  40         /* Update last 4 bytes */
  41         ve[0] = vsetq_lane_u32(vgetq_lane_u32(te[0], 3), ve[0], 3);
  42         ve[1] = vsetq_lane_u32(vgetq_lane_u32(te[1], 3), ve[1], 3);
  43         ve[2] = vsetq_lane_u32(vgetq_lane_u32(te[2], 3), ve[2], 3);
  44         ve[3] = vsetq_lane_u32(vgetq_lane_u32(te[3], 3), ve[3], 3);
  45
  46         vst1q_u32(p[0], ve[0]);
  47         vst1q_u32(p[1], ve[1]);
  48         vst1q_u32(p[2], ve[2]);
  49         vst1q_u32(p[3], ve[3]);
  50
  51         rfc1812_process((struct ipv4_hdr *)((struct ether_hdr *)p[0] + 1),
  52                 &dst_port[0], pkt[0]->packet_type);
  53         rfc1812_process((struct ipv4_hdr *)((struct ether_hdr *)p[1] + 1),
  54                 &dst_port[1], pkt[1]->packet_type);
  55         rfc1812_process((struct ipv4_hdr *)((struct ether_hdr *)p[2] + 1),
  56                 &dst_port[2], pkt[2]->packet_type);
  57         rfc1812_process((struct ipv4_hdr *)((struct ether_hdr *)p[3] + 1),
  58                 &dst_port[3], pkt[3]->packet_type);
  59 }
  60
  61 /*
  62  * Group consecutive packets with the same destination port in bursts of 4.
  63  * Suppose we have array of destionation ports:
  64  * dst_port[] = {a, b, c, d,, e, ... }
  65  * dp1 should contain: <a, b, c, d>, dp2: <b, c, d, e>.
  66  * We doing 4 comparisons at once and the result is 4 bit mask.
  67  * This mask is used as an index into prebuild array of pnum values.
  68  */
  69 static inline uint16_t *
  70 port_groupx4(uint16_t pn[FWDSTEP + 1], uint16_t *lp, uint16x8_t dp1,
  71              uint16x8_t dp2)
  72 {
  73         union {
  74                 uint16_t u16[FWDSTEP + 1];
  75                 uint64_t u64;
  76         } *pnum = (void *)pn;
  77
  78         int32_t v;
  79         uint16x8_t mask = {1, 2, 4, 8, 0, 0, 0, 0};
  80
  81         dp1 = vceqq_u16(dp1, dp2);
  82         dp1 = vandq_u16(dp1, mask);
  83         v = vaddvq_u16(dp1);
  84
  85         /* update last port counter. */
  86         lp[0] += gptbl[v].lpv;
  87         rte_compiler_barrier();
  88
  89         /* if dest port value has changed. */
  90         if (v != GRPMSK) {
  91                 pnum->u64 = gptbl[v].pnum;
  92                 pnum->u16[FWDSTEP] = 1;
  93                 lp = pnum->u16 + gptbl[v].idx;
  94         }
  95
  96         return lp;
  97 }
  98
  99 /**
 100  * Process one packet:
 101  * Update source and destination MAC addresses in the ethernet header.
 102  * Perform RFC1812 checks and updates for IPV4 packets.
 103  */
 104 static inline void
 105 process_packet(struct rte_mbuf *pkt, uint16_t *dst_port)
 106 {
 107         struct ether_hdr *eth_hdr;
 108         uint32x4_t te, ve;
 109
 110         eth_hdr = rte_pktmbuf_mtod(pkt, struct ether_hdr *);
 111
 112         te = vld1q_u32((uint32_t *)eth_hdr);
 113         ve = vreinterpretq_u32_s32(val_eth[dst_port[0]]);
 114
 115
 116         rfc1812_process((struct ipv4_hdr *)(eth_hdr + 1), dst_port,
 117                         pkt->packet_type);
 118
 119         ve = vcopyq_laneq_u32(ve, 3, te, 3);
 120         vst1q_u32((uint32_t *)eth_hdr, ve);
 121 }
 122
 123 /**
 124  * Send packets burst from pkts_burst to the ports in dst_port array
 125  */
 126 static __rte_always_inline void
 127 send_packets_multi(struct lcore_conf *qconf, struct rte_mbuf **pkts_burst,
 128                 uint16_t dst_port[MAX_PKT_BURST], int nb_rx)
 129 {
 130         int32_t k;
 131         int j = 0;
 132         uint16_t dlp;
 133         uint16_t *lp;
 134         uint16_t pnum[MAX_PKT_BURST + 1];
 135
 136         /*
 137          * Finish packet processing and group consecutive
 138          * packets with the same destination port.
 139          */
 140         k = RTE_ALIGN_FLOOR(nb_rx, FWDSTEP);
 141         if (k != 0) {
 142                 uint16x8_t dp1, dp2;
 143
 144                 lp = pnum;
 145                 lp[0] = 1;
 146
 147                 processx4_step3(pkts_burst, dst_port);
 148
 149                 /* dp1: <d[0], d[1], d[2], d[3], ... > */
 150                 dp1 = vld1q_u16(dst_port);
 151
 152                 for (j = FWDSTEP; j != k; j += FWDSTEP) {
 153                         processx4_step3(&pkts_burst[j], &dst_port[j]);
 154
 155                         /*
 156                          * dp2:
 157                          * <d[j-3], d[j-2], d[j-1], d[j], ... >
 158                          */
 159                         dp2 = vld1q_u16(&dst_port[j - FWDSTEP + 1]);
 160                         lp  = port_groupx4(&pnum[j - FWDSTEP], lp, dp1, dp2);
 161
 162                         /*
 163                          * dp1:
 164                          * <d[j], d[j+1], d[j+2], d[j+3], ... >
 165                          */
 166                         dp1 = vextq_u16(dp2, dp1, FWDSTEP - 1);
 167                 }
 168
 169                 /*
 170                  * dp2: <d[j-3], d[j-2], d[j-1], d[j-1], ... >
 171                  */
 172                 dp2 = vextq_u16(dp1, dp1, 1);
 173                 dp2 = vsetq_lane_u16(vgetq_lane_u16(dp2, 2), dp2, 3);
 174                 lp  = port_groupx4(&pnum[j - FWDSTEP], lp, dp1, dp2);
 175
 176                 /*
 177                  * remove values added by the last repeated
 178                  * dst port.
 179                  */
 180                 lp[0]--;
 181                 dlp = dst_port[j - 1];
 182         } else {
 183                 /* set dlp and lp to the never used values. */
 184                 dlp = BAD_PORT - 1;
 185                 lp = pnum + MAX_PKT_BURST;
 186         }
 187
 188         /* Process up to last 3 packets one by one. */
 189         switch (nb_rx % FWDSTEP) {
 190         case 3:
 191                 process_packet(pkts_burst[j], dst_port + j);
 192                 GROUP_PORT_STEP(dlp, dst_port, lp, pnum, j);
 193                 j++;
 194                 /* fallthrough */
 195         case 2:
 196                 process_packet(pkts_burst[j], dst_port + j);
 197                 GROUP_PORT_STEP(dlp, dst_port, lp, pnum, j);
 198                 j++;
 199                 /* fallthrough */
 200         case 1:
 201                 process_packet(pkts_burst[j], dst_port + j);
 202                 GROUP_PORT_STEP(dlp, dst_port, lp, pnum, j);
 203                 j++;
 204         }
 205
 206         /*
 207          * Send packets out, through destination port.
 208          * Consecutive packets with the same destination port
 209          * are already grouped together.
 210          * If destination port for the packet equals BAD_PORT,
 211          * then free the packet without sending it out.
 212          */
 213         for (j = 0; j < nb_rx; j += k) {
 214
 215                 int32_t m;
 216                 uint16_t pn;
 217
 218                 pn = dst_port[j];
 219                 k = pnum[j];
 220
 221                 if (likely(pn != BAD_PORT))
 222                         send_packetsx4(qconf, pn, pkts_burst + j, k);
 223                 else
 224                         for (m = j; m != j + k; m++)
 225                                 rte_pktmbuf_free(pkts_burst[m]);
 226
 227         }
 228 }
 229
 230 #endif /* _L3FWD_NEON_H_ */