summaryrefslogtreecommitdiffstats
path: root/src/vnet/ip/ip_types.h
AgeCommit message (Expand)AuthorFilesLines
2021-01-21ip: Use correct enum type in ip_address_setNeale Ranns1-1/+2
2020-11-27ip: Sub Address Family types. Feature enable for each SAFINeale Ranns1-0/+34
2020-11-20ip-neighbor: Use ip_address_t rather than ip46_address_tNeale Ranns1-2/+2
2020-09-17teib: Use ip_address_t not ip46_address_tNeale Ranns1-0/+1
2020-03-17ip: ip_address_t uses ip46_address_tNeale Ranns1-12/+29
2020-02-25vlib: Punt reason allocation listener enable/disable callbackNeale Ranns1-0/+2
2020-02-21ipsec: IPSec protection for multi-point tunnel interfacesNeale Ranns1-2/+8
2019-11-12ip: IP address and prefix types (moved from LISP)Neale Ranns1-0/+98
84' href='#n184'>184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717
/*
 * Copyright (c) 2017 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <math.h>
#include <vlib/vlib.h>
#include <vnet/vnet.h>
#include <vnet/tcp/tcp.h>
#include <vppinfra/elog.h>
#include <vnet/session/application.h>
#include <vnet/session/session_debug.h>
#include <vlibmemory/unix_shared_memory_queue.h>

vlib_node_registration_t session_queue_node;

typedef struct
{
  u32 session_index;
  u32 server_thread_index;
} session_queue_trace_t;

/* packet trace format function */
static u8 *
format_session_queue_trace (u8 * s, va_list * args)
{
  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  session_queue_trace_t *t = va_arg (*args, session_queue_trace_t *);

  s = format (s, "SESSION_QUEUE: session index %d, server thread index %d",
	      t->session_index, t->server_thread_index);
  return s;
}

vlib_node_registration_t session_queue_node;

#define foreach_session_queue_error		\
_(TX, "Packets transmitted")                  	\
_(TIMER, "Timer events")			\
_(NO_BUFFER, "Out of buffers")

typedef enum
{
#define _(sym,str) SESSION_QUEUE_ERROR_##sym,
  foreach_session_queue_error
#undef _
    SESSION_QUEUE_N_ERROR,
} session_queue_error_t;

static char *session_queue_error_strings[] = {
#define _(sym,string) string,
  foreach_session_queue_error
#undef _
};

static u32 session_type_to_next[] = {
  SESSION_QUEUE_NEXT_TCP_IP4_OUTPUT,
  SESSION_QUEUE_NEXT_IP4_LOOKUP,
  SESSION_QUEUE_NEXT_TCP_IP6_OUTPUT,
  SESSION_QUEUE_NEXT_IP6_LOOKUP,
};

always_inline void
session_tx_fifo_chain_tail (session_manager_main_t * smm, vlib_main_t * vm,
			    u8 thread_index, svm_fifo_t * fifo,
			    vlib_buffer_t * b0, u32 bi0, u8 n_bufs_per_seg,
			    u32 left_from_seg, u32 * left_to_snd0,
			    u16 * n_bufs, u32 * tx_offset, u16 deq_per_buf,
			    u8 peek_data)
{
  vlib_buffer_t *chain_b0, *prev_b0;
  u32 chain_bi0, to_deq;
  u16 len_to_deq0, n_bytes_read;
  u8 *data0, j;

  b0->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
  b0->total_length_not_including_first_buffer = 0;

  chain_bi0 = bi0;
  chain_b0 = b0;
  to_deq = left_from_seg;
  for (j = 1; j < n_bufs_per_seg; j++)
    {
      prev_b0 = chain_b0;
      len_to_deq0 = clib_min (to_deq, deq_per_buf);

      *n_bufs -= 1;
      chain_bi0 = smm->tx_buffers[thread_index][*n_bufs];
      _vec_len (smm->tx_buffers[thread_index]) = *n_bufs;

      chain_b0 = vlib_get_buffer (vm, chain_bi0);
      chain_b0->current_data = 0;
      data0 = vlib_buffer_get_current (chain_b0);
      if (peek_data)
	{
	  n_bytes_read = svm_fifo_peek (fifo, *tx_offset, len_to_deq0, data0);
	  *tx_offset += n_bytes_read;
	}
      else
	{
	  n_bytes_read = svm_fifo_dequeue_nowait (fifo, len_to_deq0, data0);
	}
      ASSERT (n_bytes_read == len_to_deq0);
      chain_b0->current_length = n_bytes_read;
      b0->total_length_not_including_first_buffer += chain_b0->current_length;

      /* update previous buffer */
      prev_b0->next_buffer = chain_bi0;
      prev_b0->flags |= VLIB_BUFFER_NEXT_PRESENT;

      /* update current buffer */
      chain_b0->next_buffer = 0;

      to_deq -= n_bytes_read;
      if (to_deq == 0)
	break;
    }
  ASSERT (to_deq == 0
	  && b0->total_length_not_including_first_buffer == left_from_seg);
  *left_to_snd0 -= left_from_seg;
}

always_inline int
session_tx_fifo_read_and_snd_i (vlib_main_t * vm, vlib_node_runtime_t * node,
				session_manager_main_t * smm,
				session_fifo_event_t * e0,
				stream_session_t * s0, u32 thread_index,
				int *n_tx_packets, u8 peek_data)
{
  u32 n_trace = vlib_get_trace_count (vm, node);
  u32 left_to_snd0, max_len_to_snd0, len_to_deq0, snd_space0;
  u32 n_bufs_per_evt, n_frames_per_evt, n_bufs_per_frame;
  transport_connection_t *tc0;
  transport_proto_vft_t *transport_vft;
  u32 next_index, next0, *to_next, n_left_to_next, bi0;
  vlib_buffer_t *b0;
  u32 tx_offset = 0, max_dequeue0, n_bytes_per_seg, left_for_seg;
  u16 snd_mss0, n_bufs_per_seg, n_bufs;
  u8 *data0;
  int i, n_bytes_read;
  u32 n_bytes_per_buf, deq_per_buf, deq_per_first_buf;
  u32 buffers_allocated, buffers_allocated_this_call;

  next_index = next0 = session_type_to_next[s0->session_type];

  transport_vft = transport_protocol_get_vft (s0->session_type);
  tc0 = transport_vft->get_connection (s0->connection_index, thread_index);

  /* Make sure we have space to send and there's something to dequeue */
  snd_mss0 = transport_vft->send_mss (tc0);
  snd_space0 = transport_vft->send_space (tc0);

  /* Can't make any progress */
  if (snd_space0 == 0 || snd_mss0 == 0)
    {
      vec_add1 (smm->pending_event_vector[thread_index], *e0);
      return 0;
    }

  /* Check how much we can pull. */
  max_dequeue0 = svm_fifo_max_dequeue (s0->server_tx_fifo);

  if (peek_data)
    {
      /* Offset in rx fifo from where to peek data */
      tx_offset = transport_vft->tx_fifo_offset (tc0);
      if (PREDICT_FALSE (tx_offset >= max_dequeue0))
	max_dequeue0 = 0;
      else
	max_dequeue0 -= tx_offset;
    }

  /* Nothing to read return */
  if (max_dequeue0 == 0)
    {
      svm_fifo_unset_event (s0->server_tx_fifo);
      return 0;
    }

  /* Ensure we're not writing more than transport window allows */
  if (max_dequeue0 < snd_space0)
    {
      /* Constrained by tx queue. Try to send only fully formed segments */
      max_len_to_snd0 = (max_dequeue0 > snd_mss0) ?
	max_dequeue0 - max_dequeue0 % snd_mss0 : max_dequeue0;
      /* TODO Nagle ? */
    }
  else
    {
      /* Expectation is that snd_space0 is already a multiple of snd_mss */
      max_len_to_snd0 = snd_space0;
    }

  n_bytes_per_buf = vlib_buffer_free_list_buffer_size
    (vm, VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX);
  ASSERT (n_bytes_per_buf > MAX_HDRS_LEN);
  n_bytes_per_seg = MAX_HDRS_LEN + snd_mss0;
  n_bufs_per_seg = ceil ((double) n_bytes_per_seg / n_bytes_per_buf);
  n_bufs_per_evt = ceil ((double) max_len_to_snd0 / n_bytes_per_seg);
  n_frames_per_evt = ceil ((double) n_bufs_per_evt / VLIB_FRAME_SIZE);
  n_bufs_per_frame = n_bufs_per_seg * VLIB_FRAME_SIZE;

  deq_per_buf = clib_min (snd_mss0, n_bytes_per_buf);
  deq_per_first_buf = clib_min (snd_mss0, n_bytes_per_buf - MAX_HDRS_LEN);

  n_bufs = vec_len (smm->tx_buffers[thread_index]);
  left_to_snd0 = max_len_to_snd0;
  for (i = 0; i < n_frames_per_evt; i++)
    {
      /* Make sure we have at least one full frame of buffers ready */
      if (PREDICT_FALSE (n_bufs < n_bufs_per_frame))
	{
	  vec_validate (smm->tx_buffers[thread_index],
			n_bufs + n_bufs_per_frame - 1);
	  buffers_allocated = 0;
	  do
	    {
	      buffers_allocated_this_call = vlib_buffer_alloc (vm,
							       &smm->tx_buffers
							       [thread_index]
							       [n_bufs +
								buffers_allocated],
							       n_bufs_per_frame
							       -
							       buffers_allocated);
	      buffers_allocated += buffers_allocated_this_call;
	    }
	  while (buffers_allocated_this_call > 0
		 && ((buffers_allocated + n_bufs < n_bufs_per_frame)));

	  n_bufs += buffers_allocated;
	  _vec_len (smm->tx_buffers[thread_index]) = n_bufs;

	  if (PREDICT_FALSE (n_bufs < n_bufs_per_frame))
	    {
	      vec_add1 (smm->pending_event_vector[thread_index], *e0);
	      return -1;
	    }
	  ASSERT (n_bufs >= n_bufs_per_frame);
	}
      /* Allow enqueuing of a new event */
      svm_fifo_unset_event (s0->server_tx_fifo);

      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
      while (left_to_snd0 && n_left_to_next)
	{
	  /*
	   * Handle first buffer in chain separately
	   */

	  /* Get free buffer */
	  ASSERT (n_bufs >= 1);
	  bi0 = smm->tx_buffers[thread_index][--n_bufs];
	  _vec_len (smm->tx_buffers[thread_index]) = n_bufs;

	  /* usual speculation, or the enqueue_x1 macro will barf */
	  to_next[0] = bi0;
	  to_next += 1;
	  n_left_to_next -= 1;

	  b0 = vlib_get_buffer (vm, bi0);
	  b0->error = 0;
	  b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
	  b0->current_data = 0;
	  b0->total_length_not_including_first_buffer = 0;

	  len_to_deq0 = clib_min (left_to_snd0, deq_per_first_buf);
	  data0 = vlib_buffer_make_headroom (b0, MAX_HDRS_LEN);
	  if (peek_data)
	    {
	      n_bytes_read = svm_fifo_peek (s0->server_tx_fifo, tx_offset,
					    len_to_deq0, data0);
	      if (n_bytes_read <= 0)
		goto dequeue_fail;
	      /* Keep track of progress locally, transport is also supposed to
	       * increment it independently when pushing the header */
	      tx_offset += n_bytes_read;
	    }
	  else
	    {
	      n_bytes_read = svm_fifo_dequeue_nowait (s0->server_tx_fifo,
						      len_to_deq0, data0);
	      if (n_bytes_read <= 0)
		goto dequeue_fail;
	    }

	  b0->current_length = n_bytes_read;

	  left_to_snd0 -= n_bytes_read;
	  *n_tx_packets = *n_tx_packets + 1;

	  /*
	   * Fill in the remaining buffers in the chain, if any
	   */
	  if (PREDICT_FALSE (n_bufs_per_seg > 1 && left_to_snd0))
	    {
	      left_for_seg = clib_min (snd_mss0 - n_bytes_read, left_to_snd0);
	      session_tx_fifo_chain_tail (smm, vm, thread_index,
					  s0->server_tx_fifo, b0, bi0,
					  n_bufs_per_seg, left_for_seg,
					  &left_to_snd0, &n_bufs, &tx_offset,
					  deq_per_buf, peek_data);
	    }

	  /* Ask transport to push header after current_length and
	   * total_length_not_including_first_buffer are updated */
	  transport_vft->push_header (tc0, b0);

	  /* *INDENT-OFF* */
	  SESSION_EVT_DBG(SESSION_EVT_DEQ, s0, ({
	      ed->data[0] = e0->event_type;
	      ed->data[1] = max_dequeue0;
	      ed->data[2] = len_to_deq0;
	      ed->data[3] = left_to_snd0;
	  }));
	  /* *INDENT-ON* */

	  VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b0);
	  if (VLIB_BUFFER_TRACE_TRAJECTORY)
	    b0->pre_data[1] = 3;

	  if (PREDICT_FALSE (n_trace > 0))
	    {
	      session_queue_trace_t *t0;
	      vlib_trace_buffer (vm, node, next_index, b0,
				 1 /* follow_chain */ );
	      vlib_set_trace_count (vm, node, --n_trace);
	      t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
	      t0->session_index = s0->session_index;
	      t0->server_thread_index = s0->thread_index;
	    }

	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
					   to_next, n_left_to_next,
					   bi0, next0);
	}
      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
    }

  /* If we couldn't dequeue all bytes mark as partially read */
  if (max_len_to_snd0 < max_dequeue0)
    {
      /* If we don't already have new event */
      if (svm_fifo_set_event (s0->server_tx_fifo))
	{
	  vec_add1 (smm->pending_event_vector[thread_index], *e0);
	}
    }
  return 0;

dequeue_fail:
  /*
   * Can't read from fifo. If we don't already have an event, save as partially
   * read, return buff to free list and return
   */
  clib_warning ("dequeue fail");

  if (svm_fifo_set_event (s0->server_tx_fifo))
    {
      vec_add1 (smm->pending_event_vector[thread_index], *e0);
    }
  vlib_put_next_frame (vm, node, next_index, n_left_to_next + 1);
  _vec_len (smm->tx_buffers[thread_index]) += 1;

  return 0;
}

int
session_tx_fifo_peek_and_snd (vlib_main_t * vm, vlib_node_runtime_t * node,
			      session_manager_main_t * smm,
			      session_fifo_event_t * e0,
			      stream_session_t * s0, u32 thread_index,
			      int *n_tx_pkts)
{
  return session_tx_fifo_read_and_snd_i (vm, node, smm, e0, s0, thread_index,
					 n_tx_pkts, 1);
}

int
session_tx_fifo_dequeue_and_snd (vlib_main_t * vm, vlib_node_runtime_t * node,
				 session_manager_main_t * smm,
				 session_fifo_event_t * e0,
				 stream_session_t * s0, u32 thread_index,
				 int *n_tx_pkts)
{
  return session_tx_fifo_read_and_snd_i (vm, node, smm, e0, s0, thread_index,
					 n_tx_pkts, 0);
}

always_inline stream_session_t *
session_event_get_session (session_fifo_event_t * e, u8 thread_index)
{
  return session_get_if_valid (e->fifo->master_session_index, thread_index);
}

void
dump_thread_0_event_queue (void)
{
  session_manager_main_t *smm = vnet_get_session_manager_main ();
  vlib_main_t *vm = &vlib_global_main;
  u32 my_thread_index = vm->thread_index;
  session_fifo_event_t _e, *e = &_e;
  stream_session_t *s0;
  int i, index;
  i8 *headp;

  unix_shared_memory_queue_t *q;
  q = smm->vpp_event_queues[my_thread_index];

  index = q->head;

  for (i = 0; i < q->cursize; i++)
    {
      headp = (i8 *) (&q->data[0] + q->elsize * index);
      clib_memcpy (e, headp, q->elsize);

      switch (e->event_type)
	{
	case FIFO_EVENT_APP_TX:
	  s0 = session_event_get_session (e, my_thread_index);
	  fformat (stdout, "[%04d] TX session %d\n", i, s0->session_index);
	  break;

	case FIFO_EVENT_DISCONNECT:
	  s0 = session_get_from_handle (e->session_handle);
	  fformat (stdout, "[%04d] disconnect session %d\n", i,
		   s0->session_index);
	  break;

	case FIFO_EVENT_BUILTIN_RX:
	  s0 = session_event_get_session (e, my_thread_index);
	  fformat (stdout, "[%04d] builtin_rx %d\n", i, s0->session_index);
	  break;

	case FIFO_EVENT_RPC:
	  fformat (stdout, "[%04d] RPC call %llx with %llx\n",
		   i, (u64) (e->rpc_args.fp), (u64) (e->rpc_args.arg));
	  break;

	default:
	  fformat (stdout, "[%04d] unhandled event type %d\n",
		   i, e->event_type);
	  break;
	}

      index++;

      if (index == q->maxsize)
	index = 0;
    }
}

static u8
session_node_cmp_event (session_fifo_event_t * e, svm_fifo_t * f)
{
  stream_session_t *s;
  switch (e->event_type)
    {
    case FIFO_EVENT_APP_RX:
    case FIFO_EVENT_APP_TX:
    case FIFO_EVENT_BUILTIN_RX:
      if (e->fifo == f)
	return 1;
      break;
    case FIFO_EVENT_DISCONNECT:
      break;
    case FIFO_EVENT_RPC:
      s = session_get_from_handle (e->session_handle);
      if (!s)
	{
	  clib_warning ("session has event but doesn't exist!");
	  break;
	}
      if (s->server_rx_fifo == f || s->server_tx_fifo == f)
	return 1;
      break;
    default:
      break;
    }
  return 0;
}

u8
session_node_lookup_fifo_event (svm_fifo_t * f, session_fifo_event_t * e)
{
  session_manager_main_t *smm = vnet_get_session_manager_main ();
  unix_shared_memory_queue_t *q;
  session_fifo_event_t *pending_event_vector, *evt;
  int i, index, found = 0;
  i8 *headp;
  u8 thread_index;

  ASSERT (e);
  thread_index = f->master_thread_index;
  /*
   * Search evt queue
   */
  q = smm->vpp_event_queues[thread_index];
  index = q->head;
  for (i = 0; i < q->cursize; i++)
    {
      headp = (i8 *) (&q->data[0] + q->elsize * index);
      clib_memcpy (e, headp, q->elsize);
      found = session_node_cmp_event (e, f);
      if (found)
	break;
      if (++index == q->maxsize)
	index = 0;
    }
  /*
   * Search pending events vector
   */
  pending_event_vector = smm->pending_event_vector[thread_index];
  vec_foreach (evt, pending_event_vector)
  {
    found = session_node_cmp_event (evt, f);
    if (found)
      {
	clib_memcpy (e, evt, sizeof (*evt));
	break;
      }
  }
  return found;
}

static uword
session_queue_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
		       vlib_frame_t * frame)
{
  session_manager_main_t *smm = vnet_get_session_manager_main ();
  session_fifo_event_t *my_pending_event_vector, *pending_disconnects, *e;
  session_fifo_event_t *my_fifo_events;
  u32 n_to_dequeue, n_events;
  unix_shared_memory_queue_t *q;
  application_t *app;
  int n_tx_packets = 0;
  u32 my_thread_index = vm->thread_index;
  int i, rv;
  f64 now = vlib_time_now (vm);
  void (*fp) (void *);

  SESSION_EVT_DBG (SESSION_EVT_POLL_GAP_TRACK, smm, my_thread_index);

  /*
   *  Update TCP time
   */
  tcp_update_time (now, my_thread_index);

  /*
   * Get vpp queue events
   */
  q = smm->vpp_event_queues[my_thread_index];
  if (PREDICT_FALSE (q == 0))
    return 0;

  my_fifo_events = smm->free_event_vector[my_thread_index];

  /* min number of events we can dequeue without blocking */
  n_to_dequeue = q->cursize;
  my_pending_event_vector = smm->pending_event_vector[my_thread_index];
  pending_disconnects = smm->pending_disconnects[my_thread_index];

  if (!n_to_dequeue && !vec_len (my_pending_event_vector)
      && !vec_len (pending_disconnects))
    return 0;

  SESSION_EVT_DBG (SESSION_EVT_DEQ_NODE, 0);

  /*
   * If we didn't manage to process previous events try going
   * over them again without dequeuing new ones.
   */
  /* XXX: Block senders to sessions that can't keep up */
  if (0 && vec_len (my_pending_event_vector) >= 100)
    {
      clib_warning ("too many fifo events unsolved");
      goto skip_dequeue;
    }

  /* See you in the next life, don't be late */
  if (pthread_mutex_trylock (&q->mutex))
    return 0;

  for (i = 0; i < n_to_dequeue; i++)
    {
      vec_add2 (my_fifo_events, e, 1);
      unix_shared_memory_queue_sub_raw (q, (u8 *) e);
    }

  /* The other side of the connection is not polling */
  if (q->cursize < (q->maxsize / 8))
    (void) pthread_cond_broadcast (&q->condvar);
  pthread_mutex_unlock (&q->mutex);

  vec_append (my_fifo_events, my_pending_event_vector);
  vec_append (my_fifo_events, smm->pending_disconnects[my_thread_index]);

  _vec_len (my_pending_event_vector) = 0;
  smm->pending_event_vector[my_thread_index] = my_pending_event_vector;
  _vec_len (smm->pending_disconnects[my_thread_index]) = 0;

skip_dequeue:
  n_events = vec_len (my_fifo_events);
  for (i = 0; i < n_events; i++)
    {
      stream_session_t *s0;	/* $$$ prefetch 1 ahead maybe */
      session_fifo_event_t *e0;

      e0 = &my_fifo_events[i];

      switch (e0->event_type)
	{
	case FIFO_EVENT_APP_TX:
	  s0 = session_event_get_session (e0, my_thread_index);

	  if (PREDICT_FALSE (!s0))
	    {
	      clib_warning ("It's dead, Jim!");
	      continue;
	    }
	  /* Can retransmit for closed sessions but can't do anything if
	   * session is not ready or closed */
	  if (PREDICT_FALSE (s0->session_state < SESSION_STATE_READY))
	    continue;
	  /* Spray packets in per session type frames, since they go to
	   * different nodes */
	  rv = (smm->session_tx_fns[s0->session_type]) (vm, node, smm, e0, s0,
							my_thread_index,
							&n_tx_packets);
	  /* Out of buffers */
	  if (PREDICT_FALSE (rv < 0))
	    {
	      vlib_node_increment_counter (vm, node->node_index,
					   SESSION_QUEUE_ERROR_NO_BUFFER, 1);
	      continue;
	    }
	  break;
	case FIFO_EVENT_DISCONNECT:
	  /* Make sure disconnects run after the pending list is drained */
	  if (!e0->postponed)
	    {
	      e0->postponed = 1;
	      vec_add1 (smm->pending_disconnects[my_thread_index], *e0);
	      continue;
	    }
	  s0 = session_get_from_handle (e0->session_handle);
	  stream_session_disconnect (s0);
	  break;
	case FIFO_EVENT_BUILTIN_RX:
	  s0 = session_event_get_session (e0, my_thread_index);
	  if (PREDICT_FALSE (!s0))
	    continue;
	  svm_fifo_unset_event (s0->server_rx_fifo);
	  app = application_get (s0->app_index);
	  app->cb_fns.builtin_server_rx_callback (s0);
	  break;
	case FIFO_EVENT_RPC:
	  fp = e0->rpc_args.fp;
	  (*fp) (e0->rpc_args.arg);
	  break;

	default:
	  clib_warning ("unhandled event type %d", e0->event_type);
	}
    }

  _vec_len (my_fifo_events) = 0;
  smm->free_event_vector[my_thread_index] = my_fifo_events;

  vlib_node_increment_counter (vm, session_queue_node.index,
			       SESSION_QUEUE_ERROR_TX, n_tx_packets);

  SESSION_EVT_DBG (SESSION_EVT_DEQ_NODE, 1);

  return n_tx_packets;
}

/* *INDENT-OFF* */
VLIB_REGISTER_NODE (session_queue_node) =
{
  .function = session_queue_node_fn,
  .name = "session-queue",
  .format_trace = format_session_queue_trace,
  .type = VLIB_NODE_TYPE_INPUT,
  .n_errors = ARRAY_LEN (session_queue_error_strings),
  .error_strings = session_queue_error_strings,
  .n_next_nodes = SESSION_QUEUE_N_NEXT,
  .state = VLIB_NODE_STATE_DISABLED,
  .next_nodes =
  {
      [SESSION_QUEUE_NEXT_DROP] = "error-drop",
      [SESSION_QUEUE_NEXT_IP4_LOOKUP] = "ip4-lookup",
      [SESSION_QUEUE_NEXT_IP6_LOOKUP] = "ip6-lookup",
      [SESSION_QUEUE_NEXT_TCP_IP4_OUTPUT] = "tcp4-output",
      [SESSION_QUEUE_NEXT_TCP_IP6_OUTPUT] = "tcp6-output",
  },
};
/* *INDENT-ON* */

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */