2 *------------------------------------------------------------------
3 * Copyright (c) 2018 Cisco and/or its affiliates.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 *------------------------------------------------------------------
18 #include <vlib/vlib.h>
19 #include <vlib/unix/unix.h>
20 #include <vlib/pci/pci.h>
21 #include <vppinfra/ring.h>
22 #include <vnet/ethernet/ethernet.h>
23 #include <vnet/devices/devices.h>
24 #include <rdma/rdma.h>
26 #define RDMA_TX_RETRIES 5
28 #define RDMA_TXQ_DV_DSEG_SZ(txq) (RDMA_MLX5_WQE_DS * RDMA_TXQ_DV_SQ_SZ(txq))
29 #define RDMA_TXQ_DV_DSEG2WQE(d) (((d) + RDMA_MLX5_WQE_DS - 1) / RDMA_MLX5_WQE_DS)
32 * MLX5 direct verbs tx/free functions
35 static_always_inline void
36 rdma_device_output_free_mlx5 (vlib_main_t * vm,
37 const vlib_node_runtime_t * node,
40 u16 idx = txq->dv_cq_idx;
41 u32 cq_mask = pow2_mask (txq->dv_cq_log2sz);
42 u32 sq_mask = pow2_mask (txq->dv_sq_log2sz);
43 u32 mask = pow2_mask (txq->bufs_log2sz);
44 u32 buf_sz = RDMA_TXQ_BUF_SZ (txq);
45 u32 log2_cq_sz = txq->dv_cq_log2sz;
46 struct mlx5_cqe64 *cqes = txq->dv_cq_cqes, *cur = cqes + (idx & cq_mask);
48 const rdma_mlx5_wqe_t *wqe;
52 op_own = *(volatile u8 *) &cur->op_own;
53 if (((idx >> log2_cq_sz) & MLX5_CQE_OWNER_MASK) !=
54 (op_own & MLX5_CQE_OWNER_MASK) || (op_own >> 4) == MLX5_CQE_INVALID)
56 if (PREDICT_FALSE ((op_own >> 4)) != MLX5_CQE_REQ)
57 vlib_error_count (vm, node->node_index, RDMA_TX_ERROR_COMPLETION, 1);
59 cur = cqes + (idx & cq_mask);
62 if (idx == txq->dv_cq_idx)
63 return; /* nothing to do */
65 cur = cqes + ((idx - 1) & cq_mask);
71 /* retrieve original WQE and get new tail counter */
72 wqe = txq->dv_sq_wqes + (be16toh (cur->wqe_counter) & sq_mask);
73 if (PREDICT_FALSE (wqe->ctrl.imm == RDMA_TXQ_DV_INVALID_ID))
74 return; /* can happen if CQE reports error for an intermediate WQE */
76 ASSERT (RDMA_TXQ_USED_SZ (txq->head, wqe->ctrl.imm) <= buf_sz &&
77 RDMA_TXQ_USED_SZ (wqe->ctrl.imm, txq->tail) < buf_sz);
79 /* free sent buffers and update txq head */
80 vlib_buffer_free_from_ring (vm, txq->bufs, txq->head & mask, buf_sz,
81 RDMA_TXQ_USED_SZ (txq->head, wqe->ctrl.imm));
82 txq->head = wqe->ctrl.imm;
85 CLIB_MEMORY_STORE_BARRIER ();
86 txq->dv_cq_dbrec[0] = htobe32 (idx);
89 static_always_inline void
90 rdma_device_output_tx_mlx5_doorbell (rdma_txq_t * txq, rdma_mlx5_wqe_t * last,
91 const u16 tail, u32 sq_mask)
93 last->ctrl.imm = tail; /* register item to free */
94 last->ctrl.fm_ce_se = MLX5_WQE_CTRL_CQ_UPDATE; /* generate a CQE so we can free buffers */
96 ASSERT (tail != txq->tail &&
97 RDMA_TXQ_AVAIL_SZ (txq, txq->head, txq->tail) >=
98 RDMA_TXQ_USED_SZ (txq->tail, tail));
100 CLIB_MEMORY_STORE_BARRIER ();
101 txq->dv_sq_dbrec[MLX5_SND_DBR] = htobe32 (tail);
102 CLIB_COMPILER_BARRIER ();
103 txq->dv_sq_db[0] = *(u64 *) last;
106 static_always_inline void
107 rdma_mlx5_wqe_init (rdma_mlx5_wqe_t * wqe, const void *tmpl,
108 vlib_buffer_t * b, const u16 tail)
110 u16 sz = b->current_length;
111 const void *cur = vlib_buffer_get_current (b);
112 uword addr = pointer_to_uword (cur);
114 clib_memcpy_fast (wqe, tmpl, RDMA_MLX5_WQE_SZ);
115 /* speculatively copy at least MLX5_ETH_L2_INLINE_HEADER_SIZE (18-bytes) */
116 STATIC_ASSERT (STRUCT_SIZE_OF (struct mlx5_wqe_eth_seg, inline_hdr_start) +
117 STRUCT_SIZE_OF (struct mlx5_wqe_eth_seg,
119 MLX5_ETH_L2_INLINE_HEADER_SIZE, "wrong size");
120 clib_memcpy_fast (wqe->eseg.inline_hdr_start, cur,
121 MLX5_ETH_L2_INLINE_HEADER_SIZE);
123 wqe->wqe_index_lo = tail;
124 wqe->wqe_index_hi = tail >> 8;
125 if (PREDICT_TRUE (sz >= MLX5_ETH_L2_INLINE_HEADER_SIZE))
127 /* inline_hdr_sz is set to MLX5_ETH_L2_INLINE_HEADER_SIZE
129 wqe->dseg.byte_count = htobe32 (sz - MLX5_ETH_L2_INLINE_HEADER_SIZE);
130 wqe->dseg.addr = htobe64 (addr + MLX5_ETH_L2_INLINE_HEADER_SIZE);
134 /* dseg.byte_count and desg.addr are set to 0 in the template */
135 wqe->eseg.inline_hdr_sz = htobe16 (sz);
140 * specific data path for chained buffers, supporting ring wrap-around
141 * contrary to the normal path - otherwise we may fail to enqueue chained
142 * buffers because we are close to the end of the ring while we still have
143 * plenty of descriptors available
145 static_always_inline u32
146 rdma_device_output_tx_mlx5_chained (vlib_main_t *vm,
147 const vlib_node_runtime_t *node,
148 const rdma_device_t *rd, rdma_txq_t *txq,
149 const u32 n_left_from, const u32 *bi,
150 vlib_buffer_t **b, u16 tail)
152 u32 wqe_n = RDMA_TXQ_AVAIL_SZ (txq, txq->head, tail);
153 u32 sq_mask = pow2_mask (txq->dv_sq_log2sz);
154 u32 mask = pow2_mask (txq->bufs_log2sz);
155 u32 dseg_mask = RDMA_TXQ_DV_DSEG_SZ (txq) - 1;
156 const u32 lkey = clib_host_to_net_u32 (rd->lkey);
157 const u32 done = RDMA_TXQ_USED_SZ (txq->tail, tail);
158 u32 n = n_left_from - done;
159 rdma_mlx5_wqe_t *last = txq->dv_sq_wqes + (tail & sq_mask);
163 while (n >= 1 && wqe_n >= 1)
165 u32 *bufs = txq->bufs + (tail & mask);
166 rdma_mlx5_wqe_t *wqe = txq->dv_sq_wqes + (tail & sq_mask);
168 /* setup the head WQE */
169 rdma_mlx5_wqe_init (wqe, txq->dv_wqe_tmpl, b[0], tail);
173 if (b[0]->flags & VLIB_BUFFER_NEXT_PRESENT)
176 * max number of available dseg:
177 * - 4 dseg per WQEBB available
178 * - max 32 dseg per WQE (5-bits length field in WQE ctrl)
180 #define RDMA_MLX5_WQE_DS_MAX (1 << 5)
182 clib_min (RDMA_MLX5_WQE_DS * (wqe_n - 1), RDMA_MLX5_WQE_DS_MAX);
183 vlib_buffer_t *chained_b = b[0];
186 /* there are exactly 4 dseg per WQEBB and we rely on that */
187 STATIC_ASSERT (RDMA_MLX5_WQE_DS *
188 sizeof (struct mlx5_wqe_data_seg) ==
189 MLX5_SEND_WQE_BB, "wrong size");
192 * iterate over fragments, supporting ring wrap-around contrary to
193 * the normal path - otherwise we may fail to enqueue chained
194 * buffers because we are close to the end of the ring while we
195 * still have plenty of descriptors available
197 while (chained_n < dseg_max
198 && chained_b->flags & VLIB_BUFFER_NEXT_PRESENT)
200 struct mlx5_wqe_data_seg *dseg = (void *) txq->dv_sq_wqes;
201 dseg += ((tail + 1) * RDMA_MLX5_WQE_DS + chained_n) & dseg_mask;
202 if (((clib_address_t) dseg & (MLX5_SEND_WQE_BB - 1)) == 0)
206 * head/tail are shared between buffers and descriptor
207 * In order to maintain 1:1 correspondance between
208 * buffer index and descriptor index, we build
209 * 4-fragments chains and save the head
211 chained_b->flags &= ~(VLIB_BUFFER_NEXT_PRESENT |
212 VLIB_BUFFER_TOTAL_LENGTH_VALID);
213 u32 idx = tail + 1 + RDMA_TXQ_DV_DSEG2WQE (chained_n);
215 txq->bufs[idx] = chained_b->next_buffer;
218 chained_b = vlib_get_buffer (vm, chained_b->next_buffer);
219 dseg->byte_count = htobe32 (chained_b->current_length);
221 dseg->addr = htobe64 (vlib_buffer_get_current_va (chained_b));
226 if (chained_b->flags & VLIB_BUFFER_NEXT_PRESENT)
229 * no descriptors left: drop the chain including 1st WQE
230 * skip the problematic packet and continue
232 vlib_buffer_free_from_ring (vm, txq->bufs, tail & mask,
233 RDMA_TXQ_BUF_SZ (txq), 1 +
234 RDMA_TXQ_DV_DSEG2WQE (chained_n));
235 vlib_error_count (vm, node->node_index,
236 dseg_max == chained_n ?
237 RDMA_TX_ERROR_SEGMENT_SIZE_EXCEEDED :
238 RDMA_TX_ERROR_NO_FREE_SLOTS, 1);
240 /* fixup tail to overwrite wqe head with next packet */
245 /* update WQE descriptor with new dseg number */
246 ((u8 *) & wqe[0].ctrl.qpn_ds)[3] = RDMA_MLX5_WQE_DS + chained_n;
248 tail += RDMA_TXQ_DV_DSEG2WQE (chained_n);
249 wqe_n -= RDMA_TXQ_DV_DSEG2WQE (chained_n);
267 if (n != n_left_from)
268 rdma_device_output_tx_mlx5_doorbell (txq, last, tail, sq_mask);
271 return n_left_from - n;
274 static_always_inline u32
275 rdma_device_output_tx_mlx5 (vlib_main_t *vm, const vlib_node_runtime_t *node,
276 const rdma_device_t *rd, rdma_txq_t *txq,
277 const u32 n_left_from, const u32 *bi,
281 u32 sq_mask = pow2_mask (txq->dv_sq_log2sz);
282 u32 mask = pow2_mask (txq->bufs_log2sz);
283 rdma_mlx5_wqe_t *wqe;
285 u16 tail = txq->tail;
287 ASSERT (RDMA_TXQ_BUF_SZ (txq) <= RDMA_TXQ_DV_SQ_SZ (txq));
289 /* avoid wrap-around logic in core loop */
290 n = clib_min (n_left_from, RDMA_TXQ_BUF_SZ (txq) - (tail & mask));
291 n_wrap = n_left_from - n;
294 wqe = txq->dv_sq_wqes + (tail & sq_mask);
298 u32 flags = b[0]->flags | b[1]->flags | b[2]->flags | b[3]->flags;
299 if (PREDICT_FALSE (flags & VLIB_BUFFER_NEXT_PRESENT))
300 return rdma_device_output_tx_mlx5_chained (vm, node, rd, txq,
301 n_left_from, bi, b, tail);
303 vlib_prefetch_buffer_header (b[4], LOAD);
304 rdma_mlx5_wqe_init (wqe + 0, txq->dv_wqe_tmpl, b[0], tail + 0);
306 vlib_prefetch_buffer_header (b[5], LOAD);
307 rdma_mlx5_wqe_init (wqe + 1, txq->dv_wqe_tmpl, b[1], tail + 1);
309 vlib_prefetch_buffer_header (b[6], LOAD);
310 rdma_mlx5_wqe_init (wqe + 2, txq->dv_wqe_tmpl, b[2], tail + 2);
312 vlib_prefetch_buffer_header (b[7], LOAD);
313 rdma_mlx5_wqe_init (wqe + 3, txq->dv_wqe_tmpl, b[3], tail + 3);
323 if (PREDICT_FALSE (b[0]->flags & VLIB_BUFFER_NEXT_PRESENT))
324 return rdma_device_output_tx_mlx5_chained (vm, node, rd, txq,
325 n_left_from, bi, b, tail);
327 rdma_mlx5_wqe_init (wqe, txq->dv_wqe_tmpl, b[0], tail);
342 rdma_device_output_tx_mlx5_doorbell (txq, &wqe[-1], tail, sq_mask);
348 * standard ibverb tx/free functions
351 static_always_inline void
352 rdma_device_output_free_ibverb (vlib_main_t * vm,
353 const vlib_node_runtime_t * node,
356 struct ibv_wc wc[VLIB_FRAME_SIZE];
357 u32 mask = pow2_mask (txq->bufs_log2sz);
361 n = ibv_poll_cq (txq->ibv_cq, VLIB_FRAME_SIZE, wc);
364 if (PREDICT_FALSE (n < 0))
365 vlib_error_count (vm, node->node_index, RDMA_TX_ERROR_COMPLETION, 1);
369 while (PREDICT_FALSE (IBV_WC_SUCCESS != wc[n - 1].status))
371 vlib_error_count (vm, node->node_index, RDMA_TX_ERROR_COMPLETION, 1);
377 tail = wc[n - 1].wr_id;
378 vlib_buffer_free_from_ring (vm, txq->bufs, txq->head & mask,
379 RDMA_TXQ_BUF_SZ (txq),
380 RDMA_TXQ_USED_SZ (txq->head, tail));
384 static_always_inline u32
385 rdma_device_output_tx_ibverb (vlib_main_t * vm,
386 const vlib_node_runtime_t * node,
387 const rdma_device_t * rd, rdma_txq_t * txq,
388 u32 n_left_from, u32 * bi, vlib_buffer_t ** b)
390 struct ibv_send_wr wr[VLIB_FRAME_SIZE], *w = wr;
391 struct ibv_sge sge[VLIB_FRAME_SIZE], *s = sge;
396 vlib_prefetch_buffer_header (b[4], LOAD);
397 s[0].addr = vlib_buffer_get_current_va (b[0]);
398 s[0].length = b[0]->current_length;
399 s[0].lkey = rd->lkey;
401 vlib_prefetch_buffer_header (b[5], LOAD);
402 s[1].addr = vlib_buffer_get_current_va (b[1]);
403 s[1].length = b[1]->current_length;
404 s[1].lkey = rd->lkey;
406 vlib_prefetch_buffer_header (b[6], LOAD);
407 s[2].addr = vlib_buffer_get_current_va (b[2]);
408 s[2].length = b[2]->current_length;
409 s[2].lkey = rd->lkey;
411 vlib_prefetch_buffer_header (b[7], LOAD);
412 s[3].addr = vlib_buffer_get_current_va (b[3]);
413 s[3].length = b[3]->current_length;
414 s[3].lkey = rd->lkey;
416 clib_memset_u8 (&w[0], 0, sizeof (w[0]));
417 w[0].next = &w[0] + 1;
418 w[0].sg_list = &s[0];
420 w[0].opcode = IBV_WR_SEND;
422 clib_memset_u8 (&w[1], 0, sizeof (w[1]));
423 w[1].next = &w[1] + 1;
424 w[1].sg_list = &s[1];
426 w[1].opcode = IBV_WR_SEND;
428 clib_memset_u8 (&w[2], 0, sizeof (w[2]));
429 w[2].next = &w[2] + 1;
430 w[2].sg_list = &s[2];
432 w[2].opcode = IBV_WR_SEND;
434 clib_memset_u8 (&w[3], 0, sizeof (w[3]));
435 w[3].next = &w[3] + 1;
436 w[3].sg_list = &s[3];
438 w[3].opcode = IBV_WR_SEND;
448 s[0].addr = vlib_buffer_get_current_va (b[0]);
449 s[0].length = b[0]->current_length;
450 s[0].lkey = rd->lkey;
452 clib_memset_u8 (&w[0], 0, sizeof (w[0]));
453 w[0].next = &w[0] + 1;
454 w[0].sg_list = &s[0];
456 w[0].opcode = IBV_WR_SEND;
464 w[-1].wr_id = txq->tail; /* register item to free */
465 w[-1].next = 0; /* fix next pointer in WR linked-list */
466 w[-1].send_flags = IBV_SEND_SIGNALED; /* generate a CQE so we can free buffers */
469 if (PREDICT_FALSE (0 != ibv_post_send (txq->ibv_qp, w, &w)))
471 vlib_error_count (vm, node->node_index, RDMA_TX_ERROR_SUBMISSION,
472 n_left_from - (w - wr));
473 n_left_from = w - wr;
475 txq->tail += n_left_from;
480 * common tx/free functions
484 rdma_device_output_free (vlib_main_t *vm, const vlib_node_runtime_t *node,
485 const rdma_device_t *rd, rdma_txq_t *txq)
487 if (PREDICT_TRUE (rd->flags & RDMA_DEVICE_F_MLX5DV))
488 rdma_device_output_free_mlx5 (vm, node, txq);
490 rdma_device_output_free_ibverb (vm, node, txq);
494 rdma_device_output_tx_try (vlib_main_t *vm, const vlib_node_runtime_t *node,
495 const rdma_device_t *rd, rdma_txq_t *txq,
496 u32 n_left_from, u32 *bi)
498 vlib_buffer_t *b[VLIB_FRAME_SIZE];
499 const u32 mask = pow2_mask (txq->bufs_log2sz);
501 /* do not enqueue more packet than ring space */
502 n_left_from = clib_min (n_left_from, RDMA_TXQ_AVAIL_SZ (txq, txq->head,
504 /* if ring is full, do nothing */
505 if (PREDICT_FALSE (n_left_from == 0))
508 /* speculatively copy buffer indices */
509 vlib_buffer_copy_indices_to_ring (txq->bufs, bi, txq->tail & mask,
510 RDMA_TXQ_BUF_SZ (txq), n_left_from);
512 vlib_get_buffers (vm, bi, b, n_left_from);
514 if (PREDICT_TRUE (rd->flags & RDMA_DEVICE_F_MLX5DV))
516 rdma_device_output_tx_mlx5 (vm, node, rd, txq, n_left_from, bi, b);
519 rdma_device_output_tx_ibverb (vm, node, rd, txq, n_left_from, bi, b);
525 rdma_device_output_tx (vlib_main_t *vm, vlib_node_runtime_t *node,
526 rdma_device_t *rd, rdma_txq_t *txq, u32 *from,
531 for (i = 0; i < RDMA_TX_RETRIES && n_left_from > 0; i++)
534 rdma_device_output_free (vm, node, rd, txq);
535 n_enq = rdma_device_output_tx_try (vm, node, rd, txq, n_left_from, from);
536 n_left_from -= n_enq;
543 VNET_DEVICE_CLASS_TX_FN (rdma_device_class) (vlib_main_t * vm,
544 vlib_node_runtime_t * node,
545 vlib_frame_t * frame)
547 rdma_main_t *rm = &rdma_main;
548 vnet_interface_output_runtime_t *ord = (void *) node->runtime_data;
549 rdma_device_t *rd = pool_elt_at_index (rm->devices, ord->dev_instance);
551 vec_elt_at_index (rd->txqs, vm->thread_index % vec_len (rd->txqs));
552 u32 *from, n_buffers, n_left;
554 ASSERT (RDMA_TXQ_BUF_SZ (txq) >= VLIB_FRAME_SIZE);
556 from = vlib_frame_vector_args (frame);
557 n_buffers = frame->n_vectors;
559 clib_spinlock_lock_if_init (&txq->lock);
561 n_left = rdma_device_output_tx (vm, node, rd, txq, from, n_buffers);
563 clib_spinlock_unlock_if_init (&txq->lock);
565 if (PREDICT_FALSE (n_left))
567 vlib_buffer_free (vm, from + n_buffers - n_left, n_left);
568 vlib_error_count (vm, node->node_index, RDMA_TX_ERROR_NO_FREE_SLOTS,
572 return n_buffers - n_left;
576 * fd.io coding-style-patch-verification: ON
579 * eval: (c-set-style "gnu")