3 #include <vlib/unix/unix.h>
4 #include <vnet/ethernet/ethernet.h>
5 #include <vnet/devices/devices.h>
6 #include <af_xdp/af_xdp.h>
8 #define AF_XDP_TX_RETRIES 5
10 static_always_inline void
11 af_xdp_device_output_free (vlib_main_t * vm, const vlib_node_runtime_t * node,
15 const u32 size = txq->cq.size;
16 const u32 mask = size - 1;
17 u32 bis[VLIB_FRAME_SIZE], *bi = bis;
19 u32 n = xsk_ring_cons__peek (&txq->cq, ARRAY_LEN (bis), &idx);
22 /* we rely on on casting addr (u64) -> bi (u32) to discard XSK offset below */
23 STATIC_ASSERT (BITS (bi[0]) + CLIB_LOG2_CACHE_LINE_BYTES <=
24 XSK_UNALIGNED_BUF_OFFSET_SHIFT, "wrong size");
25 ASSERT (mask == txq->cq.mask);
30 compl = xsk_ring_cons__comp_addr (&txq->cq, idx);
31 n = clib_min (n_free, size - (idx & mask));
38 #ifdef CLIB_HAVE_VEC256
39 u64x4 b0 = (*(u64x4u *) (compl + 0)) >> CLIB_LOG2_CACHE_LINE_BYTES;
40 u64x4 b1 = (*(u64x4u *) (compl + 4)) >> CLIB_LOG2_CACHE_LINE_BYTES;
41 /* permute 256-bit register so lower u32s of each buffer index are
42 * placed into lower 128-bits */
43 const u32x8 mask = { 0, 2, 4, 6, 1, 3, 5, 7 };
44 u32x8 b2 = u32x8_permute ((u32x8) b0, mask);
45 u32x8 b3 = u32x8_permute ((u32x8) b1, mask);
46 /* extract lower 128-bits and save them to the array of buffer indices */
47 *(u32x4u *) (bi + 0) = u32x8_extract_lo (b2);
48 *(u32x4u *) (bi + 4) = u32x8_extract_lo (b3);
50 bi[0] = compl[0] >> CLIB_LOG2_CACHE_LINE_BYTES;
51 bi[1] = compl[1] >> CLIB_LOG2_CACHE_LINE_BYTES;
52 bi[2] = compl[2] >> CLIB_LOG2_CACHE_LINE_BYTES;
53 bi[3] = compl[3] >> CLIB_LOG2_CACHE_LINE_BYTES;
54 bi[4] = compl[4] >> CLIB_LOG2_CACHE_LINE_BYTES;
55 bi[5] = compl[5] >> CLIB_LOG2_CACHE_LINE_BYTES;
56 bi[6] = compl[6] >> CLIB_LOG2_CACHE_LINE_BYTES;
57 bi[7] = compl[7] >> CLIB_LOG2_CACHE_LINE_BYTES;
66 bi[0] = compl[0] >> CLIB_LOG2_CACHE_LINE_BYTES;
67 ASSERT (vlib_buffer_is_known (vm, bi[0]) ==
68 VLIB_BUFFER_KNOWN_ALLOCATED);
76 compl = xsk_ring_cons__comp_addr (&txq->cq, 0);
82 xsk_ring_cons__release (&txq->cq, n_free);
83 vlib_buffer_free (vm, bis, n_free);
86 static_always_inline void
87 af_xdp_device_output_tx_db (vlib_main_t * vm,
88 const vlib_node_runtime_t * node,
90 af_xdp_txq_t * txq, const u32 n_tx)
92 xsk_ring_prod__submit (&txq->tx, n_tx);
94 if (!xsk_ring_prod__needs_wakeup (&txq->tx))
97 vlib_error_count (vm, node->node_index, AF_XDP_TX_ERROR_SYSCALL_REQUIRED, 1);
99 clib_spinlock_lock_if_init (&txq->syscall_lock);
101 if (xsk_ring_prod__needs_wakeup (&txq->tx))
103 const struct msghdr msg = {};
105 /* On tx, xsk socket will only tx up to TX_BATCH_SIZE, as defined in
106 * kernel net/xdp/xsk.c. Unfortunately we do not know how much this is,
107 * our only option is to retry until everything is sent... */
110 ret = sendmsg (txq->xsk_fd, &msg, MSG_DONTWAIT);
112 while (ret < 0 && EAGAIN == errno);
113 if (PREDICT_FALSE (ret < 0))
115 /* not EAGAIN: something bad is happening */
116 vlib_error_count (vm, node->node_index,
117 AF_XDP_TX_ERROR_SYSCALL_FAILURES, 1);
118 af_xdp_device_error (ad, "tx poll() failed");
122 clib_spinlock_unlock_if_init (&txq->syscall_lock);
125 static_always_inline u32
126 af_xdp_device_output_tx_try (vlib_main_t * vm,
127 const vlib_node_runtime_t * node,
128 af_xdp_device_t * ad, af_xdp_txq_t * txq,
131 vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
132 const uword start = vm->buffer_main->buffer_mem_start;
133 const u32 size = txq->tx.size;
134 const u32 mask = size - 1;
135 struct xdp_desc *desc;
139 ASSERT (mask == txq->cq.mask);
141 n_tx = xsk_ring_prod__reserve (&txq->tx, n_tx, &idx);
143 /* if ring is full, do nothing */
144 if (PREDICT_FALSE (0 == n_tx))
147 vlib_get_buffers (vm, bi, bufs, n_tx);
149 desc = xsk_ring_prod__tx_desc (&txq->tx, idx);
150 n = clib_min (n_tx, size - (idx & mask));
157 vlib_prefetch_buffer_header (b[4], LOAD);
159 (sizeof (vlib_buffer_t) +
160 b[0]->current_data) << XSK_UNALIGNED_BUF_OFFSET_SHIFT;
161 addr = pointer_to_uword (b[0]) - start;
162 desc[0].addr = offset | addr;
163 desc[0].len = b[0]->current_length;
165 vlib_prefetch_buffer_header (b[5], LOAD);
167 (sizeof (vlib_buffer_t) +
168 b[1]->current_data) << XSK_UNALIGNED_BUF_OFFSET_SHIFT;
169 addr = pointer_to_uword (b[1]) - start;
170 desc[1].addr = offset | addr;
171 desc[1].len = b[1]->current_length;
173 vlib_prefetch_buffer_header (b[6], LOAD);
175 (sizeof (vlib_buffer_t) +
176 b[2]->current_data) << XSK_UNALIGNED_BUF_OFFSET_SHIFT;
177 addr = pointer_to_uword (b[2]) - start;
178 desc[2].addr = offset | addr;
179 desc[2].len = b[2]->current_length;
181 vlib_prefetch_buffer_header (b[7], LOAD);
183 (sizeof (vlib_buffer_t) +
184 b[3]->current_data) << XSK_UNALIGNED_BUF_OFFSET_SHIFT;
185 addr = pointer_to_uword (b[3]) - start;
186 desc[3].addr = offset | addr;
187 desc[3].len = b[3]->current_length;
197 (sizeof (vlib_buffer_t) +
198 b[0]->current_data) << XSK_UNALIGNED_BUF_OFFSET_SHIFT;
199 addr = pointer_to_uword (b[0]) - start;
200 desc[0].addr = offset | addr;
201 desc[0].len = b[0]->current_length;
209 desc = xsk_ring_prod__tx_desc (&txq->tx, 0);
218 VNET_DEVICE_CLASS_TX_FN (af_xdp_device_class) (vlib_main_t * vm,
219 vlib_node_runtime_t * node,
220 vlib_frame_t * frame)
222 af_xdp_main_t *rm = &af_xdp_main;
223 vnet_interface_output_runtime_t *ord = (void *) node->runtime_data;
224 af_xdp_device_t *ad = pool_elt_at_index (rm->devices, ord->dev_instance);
225 const vnet_hw_if_tx_frame_t *tf = vlib_frame_scalar_args (frame);
226 const int shared_queue = tf->shared_queue;
227 af_xdp_txq_t *txq = vec_elt_at_index (ad->txqs, tf->queue_id);
232 from = vlib_frame_vector_args (frame);
233 n_tx = frame->n_vectors;
236 clib_spinlock_lock (&txq->lock);
238 for (i = 0, n = 0; i < AF_XDP_TX_RETRIES && n < n_tx; i++)
241 af_xdp_device_output_free (vm, node, txq);
243 af_xdp_device_output_tx_try (vm, node, ad, txq, n_tx - n, from + n);
247 af_xdp_device_output_tx_db (vm, node, ad, txq, n);
250 clib_spinlock_unlock (&txq->lock);
252 if (PREDICT_FALSE (n != n_tx))
254 vlib_buffer_free (vm, from + n, n_tx - n);
255 vlib_error_count (vm, node->node_index,
256 AF_XDP_TX_ERROR_NO_FREE_SLOTS, n_tx - n);
263 * fd.io coding-style-patch-verification: ON
266 * eval: (c-set-style "gnu")