drivers/net/mlx5/mlx5_rxtx.c

   1 /*-
   2  *   BSD LICENSE
   3  *
   4  *   Copyright 2015 6WIND S.A.
   5  *   Copyright 2015 Mellanox.
   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 6WIND S.A. 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 <assert.h>
  35 #include <stdint.h>
  36 #include <string.h>
  37 #include <stdlib.h>
  38
  39 /* Verbs header. */
  40 /* ISO C doesn't support unnamed structs/unions, disabling -pedantic. */
  41 #ifdef PEDANTIC
  42 #pragma GCC diagnostic ignored "-pedantic"
  43 #endif
  44 #include <infiniband/verbs.h>
  45 #ifdef PEDANTIC
  46 #pragma GCC diagnostic error "-pedantic"
  47 #endif
  48
  49 /* DPDK headers don't like -pedantic. */
  50 #ifdef PEDANTIC
  51 #pragma GCC diagnostic ignored "-pedantic"
  52 #endif
  53 #include <rte_mbuf.h>
  54 #include <rte_mempool.h>
  55 #include <rte_prefetch.h>
  56 #include <rte_common.h>
  57 #include <rte_branch_prediction.h>
  58 #ifdef PEDANTIC
  59 #pragma GCC diagnostic error "-pedantic"
  60 #endif
  61
  62 #include "mlx5.h"
  63 #include "mlx5_utils.h"
  64 #include "mlx5_rxtx.h"
  65 #include "mlx5_defs.h"
  66
  67 /**
  68  * Manage TX completions.
  69  *
  70  * When sending a burst, mlx5_tx_burst() posts several WRs.
  71  * To improve performance, a completion event is only required once every
  72  * MLX5_PMD_TX_PER_COMP_REQ sends. Doing so discards completion information
  73  * for other WRs, but this information would not be used anyway.
  74  *
  75  * @param txq
  76  *   Pointer to TX queue structure.
  77  *
  78  * @return
  79  *   0 on success, -1 on failure.
  80  */
  81 static int
  82 txq_complete(struct txq *txq)
  83 {
  84         unsigned int elts_comp = txq->elts_comp;
  85         unsigned int elts_tail = txq->elts_tail;
  86         const unsigned int elts_n = txq->elts_n;
  87         int wcs_n;
  88
  89         if (unlikely(elts_comp == 0))
  90                 return 0;
  91 #ifdef DEBUG_SEND
  92         DEBUG("%p: processing %u work requests completions",
  93               (void *)txq, elts_comp);
  94 #endif
  95         wcs_n = txq->if_cq->poll_cnt(txq->cq, elts_comp);
  96         if (unlikely(wcs_n == 0))
  97                 return 0;
  98         if (unlikely(wcs_n < 0)) {
  99                 DEBUG("%p: ibv_poll_cq() failed (wcs_n=%d)",
 100                       (void *)txq, wcs_n);
 101                 return -1;
 102         }
 103         elts_comp -= wcs_n;
 104         assert(elts_comp <= txq->elts_comp);
 105         /*
 106          * Assume WC status is successful as nothing can be done about it
 107          * anyway.
 108          */
 109         elts_tail += wcs_n * txq->elts_comp_cd_init;
 110         if (elts_tail >= elts_n)
 111                 elts_tail -= elts_n;
 112         txq->elts_tail = elts_tail;
 113         txq->elts_comp = elts_comp;
 114         return 0;
 115 }
 116
 117 /**
 118  * Get Memory Region (MR) <-> Memory Pool (MP) association from txq->mp2mr[].
 119  * Add MP to txq->mp2mr[] if it's not registered yet. If mp2mr[] is full,
 120  * remove an entry first.
 121  *
 122  * @param txq
 123  *   Pointer to TX queue structure.
 124  * @param[in] mp
 125  *   Memory Pool for which a Memory Region lkey must be returned.
 126  *
 127  * @return
 128  *   mr->lkey on success, (uint32_t)-1 on failure.
 129  */
 130 static uint32_t
 131 txq_mp2mr(struct txq *txq, struct rte_mempool *mp)
 132 {
 133         unsigned int i;
 134         struct ibv_mr *mr;
 135
 136         for (i = 0; (i != RTE_DIM(txq->mp2mr)); ++i) {
 137                 if (unlikely(txq->mp2mr[i].mp == NULL)) {
 138                         /* Unknown MP, add a new MR for it. */
 139                         break;
 140                 }
 141                 if (txq->mp2mr[i].mp == mp) {
 142                         assert(txq->mp2mr[i].lkey != (uint32_t)-1);
 143                         assert(txq->mp2mr[i].mr->lkey == txq->mp2mr[i].lkey);
 144                         return txq->mp2mr[i].lkey;
 145                 }
 146         }
 147         /* Add a new entry, register MR first. */
 148         DEBUG("%p: discovered new memory pool %p", (void *)txq, (void *)mp);
 149         mr = ibv_reg_mr(txq->priv->pd,
 150                         (void *)mp->elt_va_start,
 151                         (mp->elt_va_end - mp->elt_va_start),
 152                         (IBV_ACCESS_LOCAL_WRITE | IBV_ACCESS_REMOTE_WRITE));
 153         if (unlikely(mr == NULL)) {
 154                 DEBUG("%p: unable to configure MR, ibv_reg_mr() failed.",
 155                       (void *)txq);
 156                 return (uint32_t)-1;
 157         }
 158         if (unlikely(i == RTE_DIM(txq->mp2mr))) {
 159                 /* Table is full, remove oldest entry. */
 160                 DEBUG("%p: MR <-> MP table full, dropping oldest entry.",
 161                       (void *)txq);
 162                 --i;
 163                 claim_zero(ibv_dereg_mr(txq->mp2mr[i].mr));
 164                 memmove(&txq->mp2mr[0], &txq->mp2mr[1],
 165                         (sizeof(txq->mp2mr) - sizeof(txq->mp2mr[0])));
 166         }
 167         /* Store the new entry. */
 168         txq->mp2mr[i].mp = mp;
 169         txq->mp2mr[i].mr = mr;
 170         txq->mp2mr[i].lkey = mr->lkey;
 171         DEBUG("%p: new MR lkey for MP %p: 0x%08" PRIu32,
 172               (void *)txq, (void *)mp, txq->mp2mr[i].lkey);
 173         return txq->mp2mr[i].lkey;
 174 }
 175
 176 #if MLX5_PMD_SGE_WR_N > 1
 177
 178 /**
 179  * Copy scattered mbuf contents to a single linear buffer.
 180  *
 181  * @param[out] linear
 182  *   Linear output buffer.
 183  * @param[in] buf
 184  *   Scattered input buffer.
 185  *
 186  * @return
 187  *   Number of bytes copied to the output buffer or 0 if not large enough.
 188  */
 189 static unsigned int
 190 linearize_mbuf(linear_t *linear, struct rte_mbuf *buf)
 191 {
 192         unsigned int size = 0;
 193         unsigned int offset;
 194
 195         do {
 196                 unsigned int len = DATA_LEN(buf);
 197
 198                 offset = size;
 199                 size += len;
 200                 if (unlikely(size > sizeof(*linear)))
 201                         return 0;
 202                 memcpy(&(*linear)[offset],
 203                        rte_pktmbuf_mtod(buf, uint8_t *),
 204                        len);
 205                 buf = NEXT(buf);
 206         } while (buf != NULL);
 207         return size;
 208 }
 209
 210 /**
 211  * Handle scattered buffers for mlx5_tx_burst().
 212  *
 213  * @param txq
 214  *   TX queue structure.
 215  * @param segs
 216  *   Number of segments in buf.
 217  * @param elt
 218  *   TX queue element to fill.
 219  * @param[in] buf
 220  *   Buffer to process.
 221  * @param elts_head
 222  *   Index of the linear buffer to use if necessary (normally txq->elts_head).
 223  * @param[out] sges
 224  *   Array filled with SGEs on success.
 225  *
 226  * @return
 227  *   A structure containing the processed packet size in bytes and the
 228  *   number of SGEs. Both fields are set to (unsigned int)-1 in case of
 229  *   failure.
 230  */
 231 static struct tx_burst_sg_ret {
 232         unsigned int length;
 233         unsigned int num;
 234 }
 235 tx_burst_sg(struct txq *txq, unsigned int segs, struct txq_elt *elt,
 236             struct rte_mbuf *buf, unsigned int elts_head,
 237             struct ibv_sge (*sges)[MLX5_PMD_SGE_WR_N])
 238 {
 239         unsigned int sent_size = 0;
 240         unsigned int j;
 241         int linearize = 0;
 242
 243         /* When there are too many segments, extra segments are
 244          * linearized in the last SGE. */
 245         if (unlikely(segs > RTE_DIM(*sges))) {
 246                 segs = (RTE_DIM(*sges) - 1);
 247                 linearize = 1;
 248         }
 249         /* Update element. */
 250         elt->buf = buf;
 251         /* Register segments as SGEs. */
 252         for (j = 0; (j != segs); ++j) {
 253                 struct ibv_sge *sge = &(*sges)[j];
 254                 uint32_t lkey;
 255
 256                 /* Retrieve Memory Region key for this memory pool. */
 257                 lkey = txq_mp2mr(txq, buf->pool);
 258                 if (unlikely(lkey == (uint32_t)-1)) {
 259                         /* MR does not exist. */
 260                         DEBUG("%p: unable to get MP <-> MR association",
 261                               (void *)txq);
 262                         /* Clean up TX element. */
 263                         elt->buf = NULL;
 264                         goto stop;
 265                 }
 266                 /* Update SGE. */
 267                 sge->addr = rte_pktmbuf_mtod(buf, uintptr_t);
 268                 if (txq->priv->vf)
 269                         rte_prefetch0((volatile void *)
 270                                       (uintptr_t)sge->addr);
 271                 sge->length = DATA_LEN(buf);
 272                 sge->lkey = lkey;
 273                 sent_size += sge->length;
 274                 buf = NEXT(buf);
 275         }
 276         /* If buf is not NULL here and is not going to be linearized,
 277          * nb_segs is not valid. */
 278         assert(j == segs);
 279         assert((buf == NULL) || (linearize));
 280         /* Linearize extra segments. */
 281         if (linearize) {
 282                 struct ibv_sge *sge = &(*sges)[segs];
 283                 linear_t *linear = &(*txq->elts_linear)[elts_head];
 284                 unsigned int size = linearize_mbuf(linear, buf);
 285
 286                 assert(segs == (RTE_DIM(*sges) - 1));
 287                 if (size == 0) {
 288                         /* Invalid packet. */
 289                         DEBUG("%p: packet too large to be linearized.",
 290                               (void *)txq);
 291                         /* Clean up TX element. */
 292                         elt->buf = NULL;
 293                         goto stop;
 294                 }
 295                 /* If MLX5_PMD_SGE_WR_N is 1, free mbuf immediately. */
 296                 if (RTE_DIM(*sges) == 1) {
 297                         do {
 298                                 struct rte_mbuf *next = NEXT(buf);
 299
 300                                 rte_pktmbuf_free_seg(buf);
 301                                 buf = next;
 302                         } while (buf != NULL);
 303                         elt->buf = NULL;
 304                 }
 305                 /* Update SGE. */
 306                 sge->addr = (uintptr_t)&(*linear)[0];
 307                 sge->length = size;
 308                 sge->lkey = txq->mr_linear->lkey;
 309                 sent_size += size;
 310         }
 311         return (struct tx_burst_sg_ret){
 312                 .length = sent_size,
 313                 .num = segs,
 314         };
 315 stop:
 316         return (struct tx_burst_sg_ret){
 317                 .length = -1,
 318                 .num = -1,
 319         };
 320 }
 321
 322 #endif /* MLX5_PMD_SGE_WR_N > 1 */
 323
 324 /**
 325  * DPDK callback for TX.
 326  *
 327  * @param dpdk_txq
 328  *   Generic pointer to TX queue structure.
 329  * @param[in] pkts
 330  *   Packets to transmit.
 331  * @param pkts_n
 332  *   Number of packets in array.
 333  *
 334  * @return
 335  *   Number of packets successfully transmitted (<= pkts_n).
 336  */
 337 uint16_t
 338 mlx5_tx_burst(void *dpdk_txq, struct rte_mbuf **pkts, uint16_t pkts_n)
 339 {
 340         struct txq *txq = (struct txq *)dpdk_txq;
 341         unsigned int elts_head = txq->elts_head;
 342         const unsigned int elts_tail = txq->elts_tail;
 343         const unsigned int elts_n = txq->elts_n;
 344         unsigned int elts_comp_cd = txq->elts_comp_cd;
 345         unsigned int elts_comp = 0;
 346         unsigned int i;
 347         unsigned int max;
 348         int err;
 349
 350         assert(elts_comp_cd != 0);
 351         txq_complete(txq);
 352         max = (elts_n - (elts_head - elts_tail));
 353         if (max > elts_n)
 354                 max -= elts_n;
 355         assert(max >= 1);
 356         assert(max <= elts_n);
 357         /* Always leave one free entry in the ring. */
 358         --max;
 359         if (max == 0)
 360                 return 0;
 361         if (max > pkts_n)
 362                 max = pkts_n;
 363         for (i = 0; (i != max); ++i) {
 364                 struct rte_mbuf *buf = pkts[i];
 365                 unsigned int elts_head_next =
 366                         (((elts_head + 1) == elts_n) ? 0 : elts_head + 1);
 367                 struct txq_elt *elt_next = &(*txq->elts)[elts_head_next];
 368                 struct txq_elt *elt = &(*txq->elts)[elts_head];
 369                 unsigned int segs = NB_SEGS(buf);
 370 #ifdef MLX5_PMD_SOFT_COUNTERS
 371                 unsigned int sent_size = 0;
 372 #endif
 373                 uint32_t send_flags = 0;
 374
 375                 /* Clean up old buffer. */
 376                 if (likely(elt->buf != NULL)) {
 377                         struct rte_mbuf *tmp = elt->buf;
 378
 379                         /* Faster than rte_pktmbuf_free(). */
 380                         do {
 381                                 struct rte_mbuf *next = NEXT(tmp);
 382
 383                                 rte_pktmbuf_free_seg(tmp);
 384                                 tmp = next;
 385                         } while (tmp != NULL);
 386                 }
 387                 /* Request TX completion. */
 388                 if (unlikely(--elts_comp_cd == 0)) {
 389                         elts_comp_cd = txq->elts_comp_cd_init;
 390                         ++elts_comp;
 391                         send_flags |= IBV_EXP_QP_BURST_SIGNALED;
 392                 }
 393                 /* Should we enable HW CKSUM offload */
 394                 if (buf->ol_flags &
 395                     (PKT_TX_IP_CKSUM | PKT_TX_TCP_CKSUM | PKT_TX_UDP_CKSUM)) {
 396                         send_flags |= IBV_EXP_QP_BURST_IP_CSUM;
 397                         /* HW does not support checksum offloads at arbitrary
 398                          * offsets but automatically recognizes the packet
 399                          * type. For inner L3/L4 checksums, only VXLAN (UDP)
 400                          * tunnels are currently supported. */
 401                         if (RTE_ETH_IS_TUNNEL_PKT(buf->packet_type))
 402                                 send_flags |= IBV_EXP_QP_BURST_TUNNEL;
 403                 }
 404                 if (likely(segs == 1)) {
 405                         uintptr_t addr;
 406                         uint32_t length;
 407                         uint32_t lkey;
 408
 409                         /* Retrieve buffer information. */
 410                         addr = rte_pktmbuf_mtod(buf, uintptr_t);
 411                         length = DATA_LEN(buf);
 412                         /* Retrieve Memory Region key for this memory pool. */
 413                         lkey = txq_mp2mr(txq, buf->pool);
 414                         if (unlikely(lkey == (uint32_t)-1)) {
 415                                 /* MR does not exist. */
 416                                 DEBUG("%p: unable to get MP <-> MR"
 417                                       " association", (void *)txq);
 418                                 /* Clean up TX element. */
 419                                 elt->buf = NULL;
 420                                 goto stop;
 421                         }
 422                         /* Update element. */
 423                         elt->buf = buf;
 424                         if (txq->priv->vf)
 425                                 rte_prefetch0((volatile void *)
 426                                               (uintptr_t)addr);
 427                         RTE_MBUF_PREFETCH_TO_FREE(elt_next->buf);
 428                         /* Put packet into send queue. */
 429 #if MLX5_PMD_MAX_INLINE > 0
 430                         if (length <= txq->max_inline)
 431                                 err = txq->if_qp->send_pending_inline
 432                                         (txq->qp,
 433                                          (void *)addr,
 434                                          length,
 435                                          send_flags);
 436                         else
 437 #endif
 438                                 err = txq->if_qp->send_pending
 439                                         (txq->qp,
 440                                          addr,
 441                                          length,
 442                                          lkey,
 443                                          send_flags);
 444                         if (unlikely(err))
 445                                 goto stop;
 446 #ifdef MLX5_PMD_SOFT_COUNTERS
 447                         sent_size += length;
 448 #endif
 449                 } else {
 450 #if MLX5_PMD_SGE_WR_N > 1
 451                         struct ibv_sge sges[MLX5_PMD_SGE_WR_N];
 452                         struct tx_burst_sg_ret ret;
 453
 454                         ret = tx_burst_sg(txq, segs, elt, buf, elts_head,
 455                                           &sges);
 456                         if (ret.length == (unsigned int)-1)
 457                                 goto stop;
 458                         RTE_MBUF_PREFETCH_TO_FREE(elt_next->buf);
 459                         /* Put SG list into send queue. */
 460                         err = txq->if_qp->send_pending_sg_list
 461                                 (txq->qp,
 462                                  sges,
 463                                  ret.num,
 464                                  send_flags);
 465                         if (unlikely(err))
 466                                 goto stop;
 467 #ifdef MLX5_PMD_SOFT_COUNTERS
 468                         sent_size += ret.length;
 469 #endif
 470 #else /* MLX5_PMD_SGE_WR_N > 1 */
 471                         DEBUG("%p: TX scattered buffers support not"
 472                               " compiled in", (void *)txq);
 473                         goto stop;
 474 #endif /* MLX5_PMD_SGE_WR_N > 1 */
 475                 }
 476                 elts_head = elts_head_next;
 477 #ifdef MLX5_PMD_SOFT_COUNTERS
 478                 /* Increment sent bytes counter. */
 479                 txq->stats.obytes += sent_size;
 480 #endif
 481         }
 482 stop:
 483         /* Take a shortcut if nothing must be sent. */
 484         if (unlikely(i == 0))
 485                 return 0;
 486 #ifdef MLX5_PMD_SOFT_COUNTERS
 487         /* Increment sent packets counter. */
 488         txq->stats.opackets += i;
 489 #endif
 490         /* Ring QP doorbell. */
 491         err = txq->if_qp->send_flush(txq->qp);
 492         if (unlikely(err)) {
 493                 /* A nonzero value is not supposed to be returned.
 494                  * Nothing can be done about it. */
 495                 DEBUG("%p: send_flush() failed with error %d",
 496                       (void *)txq, err);
 497         }
 498         txq->elts_head = elts_head;
 499         txq->elts_comp += elts_comp;
 500         txq->elts_comp_cd = elts_comp_cd;
 501         return i;
 502 }
 503
 504 /**
 505  * Translate RX completion flags to packet type.
 506  *
 507  * @param flags
 508  *   RX completion flags returned by poll_length_flags().
 509  *
 510  * @return
 511  *   Packet type for struct rte_mbuf.
 512  */
 513 static inline uint32_t
 514 rxq_cq_to_pkt_type(uint32_t flags)
 515 {
 516         uint32_t pkt_type;
 517
 518         if (flags & IBV_EXP_CQ_RX_TUNNEL_PACKET)
 519                 pkt_type =
 520                         TRANSPOSE(flags,
 521                                   IBV_EXP_CQ_RX_OUTER_IPV4_PACKET,
 522                                   RTE_PTYPE_L3_IPV4) |
 523                         TRANSPOSE(flags,
 524                                   IBV_EXP_CQ_RX_OUTER_IPV6_PACKET,
 525                                   RTE_PTYPE_L3_IPV6) |
 526                         TRANSPOSE(flags,
 527                                   IBV_EXP_CQ_RX_IPV4_PACKET,
 528                                   RTE_PTYPE_INNER_L3_IPV4) |
 529                         TRANSPOSE(flags,
 530                                   IBV_EXP_CQ_RX_IPV6_PACKET,
 531                                   RTE_PTYPE_INNER_L3_IPV6);
 532         else
 533                 pkt_type =
 534                         TRANSPOSE(flags,
 535                                   IBV_EXP_CQ_RX_IPV4_PACKET,
 536                                   RTE_PTYPE_L3_IPV4) |
 537                         TRANSPOSE(flags,
 538                                   IBV_EXP_CQ_RX_IPV6_PACKET,
 539                                   RTE_PTYPE_L3_IPV6);
 540         return pkt_type;
 541 }
 542
 543 /**
 544  * Translate RX completion flags to offload flags.
 545  *
 546  * @param[in] rxq
 547  *   Pointer to RX queue structure.
 548  * @param flags
 549  *   RX completion flags returned by poll_length_flags().
 550  *
 551  * @return
 552  *   Offload flags (ol_flags) for struct rte_mbuf.
 553  */
 554 static inline uint32_t
 555 rxq_cq_to_ol_flags(const struct rxq *rxq, uint32_t flags)
 556 {
 557         uint32_t ol_flags = 0;
 558
 559         if (rxq->csum)
 560                 ol_flags |=
 561                         TRANSPOSE(~flags,
 562                                   IBV_EXP_CQ_RX_IP_CSUM_OK,
 563                                   PKT_RX_IP_CKSUM_BAD) |
 564                         TRANSPOSE(~flags,
 565                                   IBV_EXP_CQ_RX_TCP_UDP_CSUM_OK,
 566                                   PKT_RX_L4_CKSUM_BAD);
 567         /*
 568          * PKT_RX_IP_CKSUM_BAD and PKT_RX_L4_CKSUM_BAD are used in place
 569          * of PKT_RX_EIP_CKSUM_BAD because the latter is not functional
 570          * (its value is 0).
 571          */
 572         if ((flags & IBV_EXP_CQ_RX_TUNNEL_PACKET) && (rxq->csum_l2tun))
 573                 ol_flags |=
 574                         TRANSPOSE(~flags,
 575                                   IBV_EXP_CQ_RX_OUTER_IP_CSUM_OK,
 576                                   PKT_RX_IP_CKSUM_BAD) |
 577                         TRANSPOSE(~flags,
 578                                   IBV_EXP_CQ_RX_OUTER_TCP_UDP_CSUM_OK,
 579                                   PKT_RX_L4_CKSUM_BAD);
 580         return ol_flags;
 581 }
 582
 583 /**
 584  * DPDK callback for RX with scattered packets support.
 585  *
 586  * @param dpdk_rxq
 587  *   Generic pointer to RX queue structure.
 588  * @param[out] pkts
 589  *   Array to store received packets.
 590  * @param pkts_n
 591  *   Maximum number of packets in array.
 592  *
 593  * @return
 594  *   Number of packets successfully received (<= pkts_n).
 595  */
 596 uint16_t
 597 mlx5_rx_burst_sp(void *dpdk_rxq, struct rte_mbuf **pkts, uint16_t pkts_n)
 598 {
 599         struct rxq *rxq = (struct rxq *)dpdk_rxq;
 600         struct rxq_elt_sp (*elts)[rxq->elts_n] = rxq->elts.sp;
 601         const unsigned int elts_n = rxq->elts_n;
 602         unsigned int elts_head = rxq->elts_head;
 603         unsigned int i;
 604         unsigned int pkts_ret = 0;
 605         int ret;
 606
 607         if (unlikely(!rxq->sp))
 608                 return mlx5_rx_burst(dpdk_rxq, pkts, pkts_n);
 609         if (unlikely(elts == NULL)) /* See RTE_DEV_CMD_SET_MTU. */
 610                 return 0;
 611         for (i = 0; (i != pkts_n); ++i) {
 612                 struct rxq_elt_sp *elt = &(*elts)[elts_head];
 613                 unsigned int len;
 614                 unsigned int pkt_buf_len;
 615                 struct rte_mbuf *pkt_buf = NULL; /* Buffer returned in pkts. */
 616                 struct rte_mbuf **pkt_buf_next = &pkt_buf;
 617                 unsigned int seg_headroom = RTE_PKTMBUF_HEADROOM;
 618                 unsigned int j = 0;
 619                 uint32_t flags;
 620
 621                 /* Sanity checks. */
 622                 assert(elts_head < rxq->elts_n);
 623                 assert(rxq->elts_head < rxq->elts_n);
 624                 ret = rxq->if_cq->poll_length_flags(rxq->cq, NULL, NULL,
 625                                                     &flags);
 626                 if (unlikely(ret < 0)) {
 627                         struct ibv_wc wc;
 628                         int wcs_n;
 629
 630                         DEBUG("rxq=%p, poll_length() failed (ret=%d)",
 631                               (void *)rxq, ret);
 632                         /* ibv_poll_cq() must be used in case of failure. */
 633                         wcs_n = ibv_poll_cq(rxq->cq, 1, &wc);
 634                         if (unlikely(wcs_n == 0))
 635                                 break;
 636                         if (unlikely(wcs_n < 0)) {
 637                                 DEBUG("rxq=%p, ibv_poll_cq() failed (wcs_n=%d)",
 638                                       (void *)rxq, wcs_n);
 639                                 break;
 640                         }
 641                         assert(wcs_n == 1);
 642                         if (unlikely(wc.status != IBV_WC_SUCCESS)) {
 643                                 /* Whatever, just repost the offending WR. */
 644                                 DEBUG("rxq=%p, wr_id=%" PRIu64 ": bad work"
 645                                       " completion status (%d): %s",
 646                                       (void *)rxq, wc.wr_id, wc.status,
 647                                       ibv_wc_status_str(wc.status));
 648 #ifdef MLX5_PMD_SOFT_COUNTERS
 649                                 /* Increment dropped packets counter. */
 650                                 ++rxq->stats.idropped;
 651 #endif
 652                                 goto repost;
 653                         }
 654                         ret = wc.byte_len;
 655                 }
 656                 if (ret == 0)
 657                         break;
 658                 len = ret;
 659                 pkt_buf_len = len;
 660                 /*
 661                  * Replace spent segments with new ones, concatenate and
 662                  * return them as pkt_buf.
 663                  */
 664                 while (1) {
 665                         struct ibv_sge *sge = &elt->sges[j];
 666                         struct rte_mbuf *seg = elt->bufs[j];
 667                         struct rte_mbuf *rep;
 668                         unsigned int seg_tailroom;
 669
 670                         assert(seg != NULL);
 671                         /*
 672                          * Fetch initial bytes of packet descriptor into a
 673                          * cacheline while allocating rep.
 674                          */
 675                         rte_prefetch0(seg);
 676                         rep = __rte_mbuf_raw_alloc(rxq->mp);
 677                         if (unlikely(rep == NULL)) {
 678                                 /*
 679                                  * Unable to allocate a replacement mbuf,
 680                                  * repost WR.
 681                                  */
 682                                 DEBUG("rxq=%p: can't allocate a new mbuf",
 683                                       (void *)rxq);
 684                                 if (pkt_buf != NULL) {
 685                                         *pkt_buf_next = NULL;
 686                                         rte_pktmbuf_free(pkt_buf);
 687                                 }
 688                                 /* Increment out of memory counters. */
 689                                 ++rxq->stats.rx_nombuf;
 690                                 ++rxq->priv->dev->data->rx_mbuf_alloc_failed;
 691                                 goto repost;
 692                         }
 693 #ifndef NDEBUG
 694                         /* Poison user-modifiable fields in rep. */
 695                         NEXT(rep) = (void *)((uintptr_t)-1);
 696                         SET_DATA_OFF(rep, 0xdead);
 697                         DATA_LEN(rep) = 0xd00d;
 698                         PKT_LEN(rep) = 0xdeadd00d;
 699                         NB_SEGS(rep) = 0x2a;
 700                         PORT(rep) = 0x2a;
 701                         rep->ol_flags = -1;
 702 #endif
 703                         assert(rep->buf_len == seg->buf_len);
 704                         assert(rep->buf_len == rxq->mb_len);
 705                         /* Reconfigure sge to use rep instead of seg. */
 706                         assert(sge->lkey == rxq->mr->lkey);
 707                         sge->addr = ((uintptr_t)rep->buf_addr + seg_headroom);
 708                         elt->bufs[j] = rep;
 709                         ++j;
 710                         /* Update pkt_buf if it's the first segment, or link
 711                          * seg to the previous one and update pkt_buf_next. */
 712                         *pkt_buf_next = seg;
 713                         pkt_buf_next = &NEXT(seg);
 714                         /* Update seg information. */
 715                         seg_tailroom = (seg->buf_len - seg_headroom);
 716                         assert(sge->length == seg_tailroom);
 717                         SET_DATA_OFF(seg, seg_headroom);
 718                         if (likely(len <= seg_tailroom)) {
 719                                 /* Last segment. */
 720                                 DATA_LEN(seg) = len;
 721                                 PKT_LEN(seg) = len;
 722                                 /* Sanity check. */
 723                                 assert(rte_pktmbuf_headroom(seg) ==
 724                                        seg_headroom);
 725                                 assert(rte_pktmbuf_tailroom(seg) ==
 726                                        (seg_tailroom - len));
 727                                 break;
 728                         }
 729                         DATA_LEN(seg) = seg_tailroom;
 730                         PKT_LEN(seg) = seg_tailroom;
 731                         /* Sanity check. */
 732                         assert(rte_pktmbuf_headroom(seg) == seg_headroom);
 733                         assert(rte_pktmbuf_tailroom(seg) == 0);
 734                         /* Fix len and clear headroom for next segments. */
 735                         len -= seg_tailroom;
 736                         seg_headroom = 0;
 737                 }
 738                 /* Update head and tail segments. */
 739                 *pkt_buf_next = NULL;
 740                 assert(pkt_buf != NULL);
 741                 assert(j != 0);
 742                 NB_SEGS(pkt_buf) = j;
 743                 PORT(pkt_buf) = rxq->port_id;
 744                 PKT_LEN(pkt_buf) = pkt_buf_len;
 745                 pkt_buf->packet_type = rxq_cq_to_pkt_type(flags);
 746                 pkt_buf->ol_flags = rxq_cq_to_ol_flags(rxq, flags);
 747
 748                 /* Return packet. */
 749                 *(pkts++) = pkt_buf;
 750                 ++pkts_ret;
 751 #ifdef MLX5_PMD_SOFT_COUNTERS
 752                 /* Increment bytes counter. */
 753                 rxq->stats.ibytes += pkt_buf_len;
 754 #endif
 755 repost:
 756                 ret = rxq->if_wq->recv_sg_list(rxq->wq,
 757                                                elt->sges,
 758                                                RTE_DIM(elt->sges));
 759                 if (unlikely(ret)) {
 760                         /* Inability to repost WRs is fatal. */
 761                         DEBUG("%p: recv_sg_list(): failed (ret=%d)",
 762                               (void *)rxq->priv,
 763                               ret);
 764                         abort();
 765                 }
 766                 if (++elts_head >= elts_n)
 767                         elts_head = 0;
 768                 continue;
 769         }
 770         if (unlikely(i == 0))
 771                 return 0;
 772         rxq->elts_head = elts_head;
 773 #ifdef MLX5_PMD_SOFT_COUNTERS
 774         /* Increment packets counter. */
 775         rxq->stats.ipackets += pkts_ret;
 776 #endif
 777         return pkts_ret;
 778 }
 779
 780 /**
 781  * DPDK callback for RX.
 782  *
 783  * The following function is the same as mlx5_rx_burst_sp(), except it doesn't
 784  * manage scattered packets. Improves performance when MRU is lower than the
 785  * size of the first segment.
 786  *
 787  * @param dpdk_rxq
 788  *   Generic pointer to RX queue structure.
 789  * @param[out] pkts
 790  *   Array to store received packets.
 791  * @param pkts_n
 792  *   Maximum number of packets in array.
 793  *
 794  * @return
 795  *   Number of packets successfully received (<= pkts_n).
 796  */
 797 uint16_t
 798 mlx5_rx_burst(void *dpdk_rxq, struct rte_mbuf **pkts, uint16_t pkts_n)
 799 {
 800         struct rxq *rxq = (struct rxq *)dpdk_rxq;
 801         struct rxq_elt (*elts)[rxq->elts_n] = rxq->elts.no_sp;
 802         const unsigned int elts_n = rxq->elts_n;
 803         unsigned int elts_head = rxq->elts_head;
 804         struct ibv_sge sges[pkts_n];
 805         unsigned int i;
 806         unsigned int pkts_ret = 0;
 807         int ret;
 808
 809         if (unlikely(rxq->sp))
 810                 return mlx5_rx_burst_sp(dpdk_rxq, pkts, pkts_n);
 811         for (i = 0; (i != pkts_n); ++i) {
 812                 struct rxq_elt *elt = &(*elts)[elts_head];
 813                 unsigned int len;
 814                 struct rte_mbuf *seg = elt->buf;
 815                 struct rte_mbuf *rep;
 816                 uint32_t flags;
 817
 818                 /* Sanity checks. */
 819                 assert(seg != NULL);
 820                 assert(elts_head < rxq->elts_n);
 821                 assert(rxq->elts_head < rxq->elts_n);
 822                 /*
 823                  * Fetch initial bytes of packet descriptor into a
 824                  * cacheline while allocating rep.
 825                  */
 826                 rte_prefetch0(seg);
 827                 rte_prefetch0(&seg->cacheline1);
 828                 ret = rxq->if_cq->poll_length_flags(rxq->cq, NULL, NULL,
 829                                                     &flags);
 830                 if (unlikely(ret < 0)) {
 831                         struct ibv_wc wc;
 832                         int wcs_n;
 833
 834                         DEBUG("rxq=%p, poll_length() failed (ret=%d)",
 835                               (void *)rxq, ret);
 836                         /* ibv_poll_cq() must be used in case of failure. */
 837                         wcs_n = ibv_poll_cq(rxq->cq, 1, &wc);
 838                         if (unlikely(wcs_n == 0))
 839                                 break;
 840                         if (unlikely(wcs_n < 0)) {
 841                                 DEBUG("rxq=%p, ibv_poll_cq() failed (wcs_n=%d)",
 842                                       (void *)rxq, wcs_n);
 843                                 break;
 844                         }
 845                         assert(wcs_n == 1);
 846                         if (unlikely(wc.status != IBV_WC_SUCCESS)) {
 847                                 /* Whatever, just repost the offending WR. */
 848                                 DEBUG("rxq=%p, wr_id=%" PRIu64 ": bad work"
 849                                       " completion status (%d): %s",
 850                                       (void *)rxq, wc.wr_id, wc.status,
 851                                       ibv_wc_status_str(wc.status));
 852 #ifdef MLX5_PMD_SOFT_COUNTERS
 853                                 /* Increment dropped packets counter. */
 854                                 ++rxq->stats.idropped;
 855 #endif
 856                                 /* Add SGE to array for repost. */
 857                                 sges[i] = elt->sge;
 858                                 goto repost;
 859                         }
 860                         ret = wc.byte_len;
 861                 }
 862                 if (ret == 0)
 863                         break;
 864                 len = ret;
 865                 rep = __rte_mbuf_raw_alloc(rxq->mp);
 866                 if (unlikely(rep == NULL)) {
 867                         /*
 868                          * Unable to allocate a replacement mbuf,
 869                          * repost WR.
 870                          */
 871                         DEBUG("rxq=%p: can't allocate a new mbuf",
 872                               (void *)rxq);
 873                         /* Increment out of memory counters. */
 874                         ++rxq->stats.rx_nombuf;
 875                         ++rxq->priv->dev->data->rx_mbuf_alloc_failed;
 876                         goto repost;
 877                 }
 878
 879                 /* Reconfigure sge to use rep instead of seg. */
 880                 elt->sge.addr = (uintptr_t)rep->buf_addr + RTE_PKTMBUF_HEADROOM;
 881                 assert(elt->sge.lkey == rxq->mr->lkey);
 882                 elt->buf = rep;
 883
 884                 /* Add SGE to array for repost. */
 885                 sges[i] = elt->sge;
 886
 887                 /* Update seg information. */
 888                 SET_DATA_OFF(seg, RTE_PKTMBUF_HEADROOM);
 889                 NB_SEGS(seg) = 1;
 890                 PORT(seg) = rxq->port_id;
 891                 NEXT(seg) = NULL;
 892                 PKT_LEN(seg) = len;
 893                 DATA_LEN(seg) = len;
 894                 seg->packet_type = rxq_cq_to_pkt_type(flags);
 895                 seg->ol_flags = rxq_cq_to_ol_flags(rxq, flags);
 896
 897                 /* Return packet. */
 898                 *(pkts++) = seg;
 899                 ++pkts_ret;
 900 #ifdef MLX5_PMD_SOFT_COUNTERS
 901                 /* Increment bytes counter. */
 902                 rxq->stats.ibytes += len;
 903 #endif
 904 repost:
 905                 if (++elts_head >= elts_n)
 906                         elts_head = 0;
 907                 continue;
 908         }
 909         if (unlikely(i == 0))
 910                 return 0;
 911         /* Repost WRs. */
 912 #ifdef DEBUG_RECV
 913         DEBUG("%p: reposting %u WRs", (void *)rxq, i);
 914 #endif
 915         ret = rxq->if_wq->recv_burst(rxq->wq, sges, i);
 916         if (unlikely(ret)) {
 917                 /* Inability to repost WRs is fatal. */
 918                 DEBUG("%p: recv_burst(): failed (ret=%d)",
 919                       (void *)rxq->priv,
 920                       ret);
 921                 abort();
 922         }
 923         rxq->elts_head = elts_head;
 924 #ifdef MLX5_PMD_SOFT_COUNTERS
 925         /* Increment packets counter. */
 926         rxq->stats.ipackets += pkts_ret;
 927 #endif
 928         return pkts_ret;
 929 }
 930
 931 /**
 932  * Dummy DPDK callback for TX.
 933  *
 934  * This function is used to temporarily replace the real callback during
 935  * unsafe control operations on the queue, or in case of error.
 936  *
 937  * @param dpdk_txq
 938  *   Generic pointer to TX queue structure.
 939  * @param[in] pkts
 940  *   Packets to transmit.
 941  * @param pkts_n
 942  *   Number of packets in array.
 943  *
 944  * @return
 945  *   Number of packets successfully transmitted (<= pkts_n).
 946  */
 947 uint16_t
 948 removed_tx_burst(void *dpdk_txq, struct rte_mbuf **pkts, uint16_t pkts_n)
 949 {
 950         (void)dpdk_txq;
 951         (void)pkts;
 952         (void)pkts_n;
 953         return 0;
 954 }
 955
 956 /**
 957  * Dummy DPDK callback for RX.
 958  *
 959  * This function is used to temporarily replace the real callback during
 960  * unsafe control operations on the queue, or in case of error.
 961  *
 962  * @param dpdk_rxq
 963  *   Generic pointer to RX queue structure.
 964  * @param[out] pkts
 965  *   Array to store received packets.
 966  * @param pkts_n
 967  *   Maximum number of packets in array.
 968  *
 969  * @return
 970  *   Number of packets successfully received (<= pkts_n).
 971  */
 972 uint16_t
 973 removed_rx_burst(void *dpdk_rxq, struct rte_mbuf **pkts, uint16_t pkts_n)
 974 {
 975         (void)dpdk_rxq;
 976         (void)pkts;
 977         (void)pkts_n;
 978         return 0;
 979 }