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 *) (txq->dv_sq_wqes + (txq->tail & sq_mask));
107 static_always_inline void
108 rdma_mlx5_wqe_init (rdma_mlx5_wqe_t * wqe, const void *tmpl,
109 vlib_buffer_t * b, const u16 tail)
111 u16 sz = b->current_length;
112 const void *cur = vlib_buffer_get_current (b);
113 uword addr = pointer_to_uword (cur);
115 clib_memcpy_fast (wqe, tmpl, RDMA_MLX5_WQE_SZ);
116 /* speculatively copy at least MLX5_ETH_L2_INLINE_HEADER_SIZE (18-bytes) */
117 clib_memcpy_fast (wqe->eseg.inline_hdr_start,
118 cur, MLX5_ETH_L2_INLINE_HEADER_SIZE);
120 wqe->wqe_index_lo = tail;
121 wqe->wqe_index_hi = tail >> 8;
122 if (PREDICT_TRUE (sz >= MLX5_ETH_L2_INLINE_HEADER_SIZE))
124 /* inline_hdr_sz is set to MLX5_ETH_L2_INLINE_HEADER_SIZE
126 wqe->dseg.byte_count = htobe32 (sz - MLX5_ETH_L2_INLINE_HEADER_SIZE);
127 wqe->dseg.addr = htobe64 (addr + MLX5_ETH_L2_INLINE_HEADER_SIZE);
131 /* dseg.byte_count and desg.addr are set to 0 in the template */
132 wqe->eseg.inline_hdr_sz = htobe16 (sz);
137 * specific data path for chained buffers, supporting ring wrap-around
138 * contrary to the normal path - otherwise we may fail to enqueue chained
139 * buffers because we are close to the end of the ring while we still have
140 * plenty of descriptors available
142 static_always_inline u32
143 rdma_device_output_tx_mlx5_chained (vlib_main_t * vm,
144 const vlib_node_runtime_t * node,
145 const rdma_device_t * rd,
146 rdma_txq_t * txq, u32 n_left_from, u32 n,
147 u32 * bi, vlib_buffer_t ** b,
148 rdma_mlx5_wqe_t * wqe, u16 tail)
150 rdma_mlx5_wqe_t *last = wqe;
151 u32 wqe_n = RDMA_TXQ_AVAIL_SZ (txq, txq->head, tail);
152 u32 sq_mask = pow2_mask (txq->dv_sq_log2sz);
153 u32 mask = pow2_mask (txq->bufs_log2sz);
154 u32 dseg_mask = RDMA_TXQ_DV_DSEG_SZ (txq) - 1;
155 const u32 lkey = wqe[0].dseg.lkey;
157 vlib_buffer_copy_indices (txq->bufs + (txq->tail & mask), bi,
160 while (n >= 1 && wqe_n >= 1)
162 u32 *bufs = txq->bufs + (tail & mask);
163 rdma_mlx5_wqe_t *wqe = txq->dv_sq_wqes + (tail & sq_mask);
165 /* setup the head WQE */
166 rdma_mlx5_wqe_init (wqe, txq->dv_wqe_tmpl, b[0], tail);
170 if (b[0]->flags & VLIB_BUFFER_NEXT_PRESENT)
173 * max number of available dseg:
174 * - 4 dseg per WQEBB available
175 * - max 32 dseg per WQE (5-bits length field in WQE ctrl)
177 #define RDMA_MLX5_WQE_DS_MAX (1 << 5)
179 clib_min (RDMA_MLX5_WQE_DS * (wqe_n - 1), RDMA_MLX5_WQE_DS_MAX);
180 vlib_buffer_t *chained_b = b[0];
183 /* there are exactly 4 dseg per WQEBB and we rely on that */
184 STATIC_ASSERT (RDMA_MLX5_WQE_DS *
185 sizeof (struct mlx5_wqe_data_seg) ==
186 MLX5_SEND_WQE_BB, "wrong size");
189 * iterate over fragments, supporting ring wrap-around contrary to
190 * the normal path - otherwise we may fail to enqueue chained
191 * buffers because we are close to the end of the ring while we
192 * still have plenty of descriptors available
194 while (chained_n < dseg_max
195 && chained_b->flags & VLIB_BUFFER_NEXT_PRESENT)
197 struct mlx5_wqe_data_seg *dseg = (void *) txq->dv_sq_wqes;
198 dseg += ((tail + 1) * RDMA_MLX5_WQE_DS + chained_n) & dseg_mask;
199 if (((clib_address_t) dseg & (MLX5_SEND_WQE_BB - 1)) == 0)
203 * head/tail are shared between buffers and descriptor
204 * In order to maintain 1:1 correspondance between
205 * buffer index and descriptor index, we build
206 * 4-fragments chains and save the head
208 chained_b->flags &= ~(VLIB_BUFFER_NEXT_PRESENT |
209 VLIB_BUFFER_TOTAL_LENGTH_VALID);
210 u32 idx = tail + 1 + RDMA_TXQ_DV_DSEG2WQE (chained_n);
212 txq->bufs[idx] = chained_b->next_buffer;
215 chained_b = vlib_get_buffer (vm, chained_b->next_buffer);
216 dseg->byte_count = htobe32 (chained_b->current_length);
218 dseg->addr = htobe64 (vlib_buffer_get_current_va (chained_b));
223 if (chained_b->flags & VLIB_BUFFER_NEXT_PRESENT)
226 * no descriptors left: drop the chain including 1st WQE
227 * skip the problematic packet and continue
229 vlib_buffer_free_from_ring (vm, txq->bufs, tail & mask,
230 RDMA_TXQ_BUF_SZ (txq), 1 +
231 RDMA_TXQ_DV_DSEG2WQE (chained_n));
232 vlib_error_count (vm, node->node_index,
233 dseg_max == chained_n ?
234 RDMA_TX_ERROR_SEGMENT_SIZE_EXCEEDED :
235 RDMA_TX_ERROR_NO_FREE_SLOTS, 1);
237 /* fixup tail to overwrite wqe head with next packet */
242 /* update WQE descriptor with new dseg number */
243 ((u8 *) & wqe[0].ctrl.qpn_ds)[3] = RDMA_MLX5_WQE_DS + chained_n;
245 tail += RDMA_TXQ_DV_DSEG2WQE (chained_n);
246 wqe_n -= RDMA_TXQ_DV_DSEG2WQE (chained_n);
264 if (n == n_left_from)
265 return 0; /* we fail to enqueue even a single packet */
267 rdma_device_output_tx_mlx5_doorbell (txq, last, tail, sq_mask);
268 return n_left_from - n;
271 static_always_inline u32
272 rdma_device_output_tx_mlx5 (vlib_main_t * vm,
273 const vlib_node_runtime_t * node,
274 const rdma_device_t * rd, rdma_txq_t * txq,
275 const u32 n_left_from, u32 * bi,
278 u32 sq_mask = pow2_mask (txq->dv_sq_log2sz);
279 u32 mask = pow2_mask (txq->bufs_log2sz);
280 rdma_mlx5_wqe_t *wqe = txq->dv_sq_wqes + (txq->tail & sq_mask);
282 u16 tail = txq->tail;
284 ASSERT (RDMA_TXQ_BUF_SZ (txq) <= RDMA_TXQ_DV_SQ_SZ (txq));
288 u32 flags = b[0]->flags | b[1]->flags | b[2]->flags | b[3]->flags;
289 if (PREDICT_FALSE (flags & VLIB_BUFFER_NEXT_PRESENT))
290 return rdma_device_output_tx_mlx5_chained (vm, node, rd, txq,
291 n_left_from, n, bi, b, wqe,
294 if (PREDICT_TRUE (n >= 8))
296 vlib_prefetch_buffer_header (b + 4, LOAD);
297 vlib_prefetch_buffer_header (b + 5, LOAD);
298 vlib_prefetch_buffer_header (b + 6, LOAD);
299 vlib_prefetch_buffer_header (b + 7, LOAD);
300 clib_prefetch_load (wqe + 4);
303 rdma_mlx5_wqe_init (wqe + 0, txq->dv_wqe_tmpl, b[0], tail + 0);
304 rdma_mlx5_wqe_init (wqe + 1, txq->dv_wqe_tmpl, b[1], tail + 1);
305 rdma_mlx5_wqe_init (wqe + 2, txq->dv_wqe_tmpl, b[2], tail + 2);
306 rdma_mlx5_wqe_init (wqe + 3, txq->dv_wqe_tmpl, b[3], tail + 3);
316 if (PREDICT_FALSE (b[0]->flags & VLIB_BUFFER_NEXT_PRESENT))
317 return rdma_device_output_tx_mlx5_chained (vm, node, rd, txq,
318 n_left_from, n, bi, b, wqe,
321 rdma_mlx5_wqe_init (wqe, txq->dv_wqe_tmpl, b[0], tail);
329 vlib_buffer_copy_indices (txq->bufs + (txq->tail & mask), bi, n_left_from);
331 rdma_device_output_tx_mlx5_doorbell (txq, &wqe[-1], tail, sq_mask);
336 * standard ibverb tx/free functions
339 static_always_inline void
340 rdma_device_output_free_ibverb (vlib_main_t * vm,
341 const vlib_node_runtime_t * node,
344 struct ibv_wc wc[VLIB_FRAME_SIZE];
345 u32 mask = pow2_mask (txq->bufs_log2sz);
349 n = ibv_poll_cq (txq->ibv_cq, VLIB_FRAME_SIZE, wc);
352 if (PREDICT_FALSE (n < 0))
353 vlib_error_count (vm, node->node_index, RDMA_TX_ERROR_COMPLETION, 1);
357 while (PREDICT_FALSE (IBV_WC_SUCCESS != wc[n - 1].status))
359 vlib_error_count (vm, node->node_index, RDMA_TX_ERROR_COMPLETION, 1);
365 tail = wc[n - 1].wr_id;
366 vlib_buffer_free_from_ring (vm, txq->bufs, txq->head & mask,
367 RDMA_TXQ_BUF_SZ (txq),
368 RDMA_TXQ_USED_SZ (txq->head, tail));
372 static_always_inline u32
373 rdma_device_output_tx_ibverb (vlib_main_t * vm,
374 const vlib_node_runtime_t * node,
375 const rdma_device_t * rd, rdma_txq_t * txq,
376 u32 n_left_from, u32 * bi, vlib_buffer_t ** b)
378 struct ibv_send_wr wr[VLIB_FRAME_SIZE], *w = wr;
379 struct ibv_sge sge[VLIB_FRAME_SIZE], *s = sge;
380 u32 mask = txq->bufs_log2sz;
383 memset (w, 0, n_left_from * sizeof (w[0]));
387 if (PREDICT_TRUE (n >= 8))
389 vlib_prefetch_buffer_header (b[4 + 0], LOAD);
390 vlib_prefetch_buffer_header (b[4 + 1], LOAD);
391 vlib_prefetch_buffer_header (b[4 + 2], LOAD);
392 vlib_prefetch_buffer_header (b[4 + 3], LOAD);
394 CLIB_PREFETCH (&s[4 + 0], 4 * sizeof (s[0]), STORE);
396 CLIB_PREFETCH (&w[4 + 0], CLIB_CACHE_LINE_BYTES, STORE);
397 CLIB_PREFETCH (&w[4 + 1], CLIB_CACHE_LINE_BYTES, STORE);
398 CLIB_PREFETCH (&w[4 + 2], CLIB_CACHE_LINE_BYTES, STORE);
399 CLIB_PREFETCH (&w[4 + 3], CLIB_CACHE_LINE_BYTES, STORE);
402 s[0].addr = vlib_buffer_get_current_va (b[0]);
403 s[0].length = b[0]->current_length;
404 s[0].lkey = rd->lkey;
406 s[1].addr = vlib_buffer_get_current_va (b[1]);
407 s[1].length = b[1]->current_length;
408 s[1].lkey = rd->lkey;
410 s[2].addr = vlib_buffer_get_current_va (b[2]);
411 s[2].length = b[2]->current_length;
412 s[2].lkey = rd->lkey;
414 s[3].addr = vlib_buffer_get_current_va (b[3]);
415 s[3].length = b[3]->current_length;
416 s[3].lkey = rd->lkey;
418 w[0].next = &w[0] + 1;
419 w[0].sg_list = &s[0];
421 w[0].opcode = IBV_WR_SEND;
423 w[1].next = &w[1] + 1;
424 w[1].sg_list = &s[1];
426 w[1].opcode = IBV_WR_SEND;
428 w[2].next = &w[2] + 1;
429 w[2].sg_list = &s[2];
431 w[2].opcode = IBV_WR_SEND;
433 w[3].next = &w[3] + 1;
434 w[3].sg_list = &s[3];
436 w[3].opcode = IBV_WR_SEND;
446 s[0].addr = vlib_buffer_get_current_va (b[0]);
447 s[0].length = b[0]->current_length;
448 s[0].lkey = rd->lkey;
450 w[0].next = &w[0] + 1;
451 w[0].sg_list = &s[0];
453 w[0].opcode = IBV_WR_SEND;
461 w[-1].wr_id = txq->tail; /* register item to free */
462 w[-1].next = 0; /* fix next pointer in WR linked-list */
463 w[-1].send_flags = IBV_SEND_SIGNALED; /* generate a CQE so we can free buffers */
466 if (PREDICT_FALSE (0 != ibv_post_send (txq->ibv_qp, w, &w)))
468 vlib_error_count (vm, node->node_index, RDMA_TX_ERROR_SUBMISSION,
469 n_left_from - (w - wr));
470 n_left_from = w - wr;
473 vlib_buffer_copy_indices (txq->bufs + (txq->tail & mask), bi, n_left_from);
474 txq->tail += n_left_from;
479 * common tx/free functions
482 static_always_inline void
483 rdma_device_output_free (vlib_main_t * vm, const vlib_node_runtime_t * node,
484 rdma_txq_t * txq, int is_mlx5dv)
487 rdma_device_output_free_mlx5 (vm, node, txq);
489 rdma_device_output_free_ibverb (vm, node, txq);
492 static_always_inline u32
493 rdma_device_output_tx_try (vlib_main_t * vm, const vlib_node_runtime_t * node,
494 const rdma_device_t * rd, rdma_txq_t * txq,
495 u32 n_left_from, u32 * bi, int is_mlx5dv)
497 vlib_buffer_t *b[VLIB_FRAME_SIZE];
498 u32 mask = pow2_mask (txq->bufs_log2sz);
500 /* do not enqueue more packet than ring space */
501 n_left_from = clib_min (n_left_from, RDMA_TXQ_AVAIL_SZ (txq, txq->head,
503 /* avoid wrap-around logic in core loop */
504 n_left_from = clib_min (n_left_from, RDMA_TXQ_BUF_SZ (txq) -
507 /* if ring is full, do nothing */
508 if (PREDICT_FALSE (n_left_from == 0))
511 vlib_get_buffers (vm, bi, b, n_left_from);
514 rdma_device_output_tx_mlx5 (vm, node, rd, txq, n_left_from, bi, b) :
515 rdma_device_output_tx_ibverb (vm, node, rd, txq, n_left_from, bi, b);
518 static_always_inline uword
519 rdma_device_output_tx (vlib_main_t * vm, vlib_node_runtime_t * node,
520 vlib_frame_t * frame, rdma_device_t * rd,
523 u32 thread_index = vm->thread_index;
525 vec_elt_at_index (rd->txqs, thread_index % vec_len (rd->txqs));
530 ASSERT (RDMA_TXQ_BUF_SZ (txq) >= VLIB_FRAME_SIZE);
532 from = vlib_frame_vector_args (frame);
533 n_left_from = frame->n_vectors;
535 clib_spinlock_lock_if_init (&txq->lock);
537 for (i = 0; i < RDMA_TX_RETRIES && n_left_from > 0; i++)
540 rdma_device_output_free (vm, node, txq, is_mlx5dv);
541 n_enq = rdma_device_output_tx_try (vm, node, rd, txq, n_left_from, from,
544 n_left_from -= n_enq;
548 clib_spinlock_unlock_if_init (&txq->lock);
550 if (PREDICT_FALSE (n_left_from))
552 vlib_buffer_free (vm, from, n_left_from);
553 vlib_error_count (vm, node->node_index,
554 RDMA_TX_ERROR_NO_FREE_SLOTS, n_left_from);
557 return frame->n_vectors - n_left_from;
560 VNET_DEVICE_CLASS_TX_FN (rdma_device_class) (vlib_main_t * vm,
561 vlib_node_runtime_t * node,
562 vlib_frame_t * frame)
564 rdma_main_t *rm = &rdma_main;
565 vnet_interface_output_runtime_t *ord = (void *) node->runtime_data;
566 rdma_device_t *rd = pool_elt_at_index (rm->devices, ord->dev_instance);
568 if (PREDICT_TRUE (rd->flags & RDMA_DEVICE_F_MLX5DV))
569 return rdma_device_output_tx (vm, node, frame, rd, 1 /* is_mlx5dv */ );
571 return rdma_device_output_tx (vm, node, frame, rd, 0 /* is_mlx5dv */ );
575 * fd.io coding-style-patch-verification: ON
578 * eval: (c-set-style "gnu")