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CSIT 18.10
==========

.. toctree::
    :numbered:

    introduction/index
    vpp_performance_tests/index
    dpdk_performance_tests/index
    vpp_functional_tests/index
    honeycomb_functional_tests/index
    nsh_sfc_functional_tests/index
    dmm_functional_tests/index
    csit_framework_documentation/index
70'>470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743
/*
 *------------------------------------------------------------------
 * memclnt_shared.c - API message handling, common code for both clients
 * and the vlib process itself.
 *
 *
 * Copyright (c) 2009 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 <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <string.h>
#include <unistd.h>
#include <signal.h>
#include <vppinfra/format.h>
#include <vppinfra/byte_order.h>
#include <vppinfra/error.h>
#include <vlib/vlib.h>
#include <vlib/unix/unix.h>
#include <vlibmemory/api.h>
#include <vlibmemory/unix_shared_memory_queue.h>

#include <vlibmemory/vl_memory_msg_enum.h>

#define vl_typedefs
#include <vlibmemory/vl_memory_api_h.h>
#undef vl_typedefs

static inline void *
vl_msg_api_alloc_internal (int nbytes, int pool)
{
  int i;
  msgbuf_t *rv;
  ring_alloc_t *ap;
  unix_shared_memory_queue_t *q;
  void *oldheap;
  vl_shmem_hdr_t *shmem_hdr;
  api_main_t *am = &api_main;

  shmem_hdr = am->shmem_hdr;

  if (shmem_hdr == 0)
    {
      clib_warning ("shared memory header NULL");
      return 0;
    }

  /* account for the msgbuf_t header */
  nbytes += sizeof (msgbuf_t);

  if (shmem_hdr->vl_rings == 0)
    {
      clib_warning ("vl_rings NULL");
      return 0;
    }

  if (shmem_hdr->client_rings == 0)
    {
      clib_warning ("client_rings NULL");
      return 0;
    }

  ap = pool ? shmem_hdr->vl_rings : shmem_hdr->client_rings;
  for (i = 0; i < vec_len (ap); i++)
    {
      /* Too big? */
      if (nbytes > ap[i].size)
	{
	  continue;
	}

      q = ap[i].rp;
      if (pool == 0)
	{
	  pthread_mutex_lock (&q->mutex);
	}
      rv = (msgbuf_t *) (&q->data[0] + q->head * q->elsize);
      /*
       * Is this item still in use?
       */
      if (rv->q)
	{
	  /* yes, loser; try next larger pool */
	  ap[i].misses++;
	  if (pool == 0)
	    pthread_mutex_unlock (&q->mutex);
	  continue;
	}
      /* OK, we have a winner */
      ap[i].hits++;
      /*
       * Remember the source queue, although we
       * don't need to know the queue to free the item.
       */
      rv->q = q;
      q->head++;
      if (q->head == q->maxsize)
	q->head = 0;

      if (pool == 0)
	pthread_mutex_unlock (&q->mutex);
      goto out;
    }

  /*
   * Request too big, or head element of all size-compatible rings
   * still in use. Fall back to shared-memory malloc.
   */
  am->ring_misses++;

  pthread_mutex_lock (&am->vlib_rp->mutex);
  oldheap = svm_push_data_heap (am->vlib_rp);
  rv = clib_mem_alloc (nbytes);
  rv->q = 0;
  svm_pop_heap (oldheap);
  pthread_mutex_unlock (&am->vlib_rp->mutex);

out:
  rv->data_len = htonl (nbytes - sizeof (msgbuf_t));
  return (rv->data);
}

void *
vl_msg_api_alloc (int nbytes)
{
  int pool;
  api_main_t *am = &api_main;
  vl_shmem_hdr_t *shmem_hdr = am->shmem_hdr;

  /*
   * Clients use pool-0, vlib proc uses pool 1
   */
  pool = (am->our_pid == shmem_hdr->vl_pid);
  return vl_msg_api_alloc_internal (nbytes, pool);
}

void *
vl_msg_api_alloc_as_if_client (int nbytes)
{
  return vl_msg_api_alloc_internal (nbytes, 0);
}

void
vl_msg_api_free (void *a)
{
  msgbuf_t *rv;
  void *oldheap;
  api_main_t *am = &api_main;

  rv = (msgbuf_t *) (((u8 *) a) - offsetof (msgbuf_t, data));

  /*
   * Here's the beauty of the scheme.  Only one proc/thread has
   * control of a given message buffer. To free a buffer, we just clear the
   * queue field, and leave. No locks, no hits, no errors...
   */
  if (rv->q)
    {
      rv->q = 0;
      return;
    }

  pthread_mutex_lock (&am->vlib_rp->mutex);
  oldheap = svm_push_data_heap (am->vlib_rp);
  clib_mem_free (rv);
  svm_pop_heap (oldheap);
  pthread_mutex_unlock (&am->vlib_rp->mutex);
}

static void
vl_msg_api_free_nolock (void *a)
{
  msgbuf_t *rv;
  void *oldheap;
  api_main_t *am = &api_main;

  rv = (msgbuf_t *) (((u8 *) a) - offsetof (msgbuf_t, data));
  /*
   * Here's the beauty of the scheme.  Only one proc/thread has
   * control of a given message buffer. To free a buffer, we just clear the
   * queue field, and leave. No locks, no hits, no errors...
   */
  if (rv->q)
    {
      rv->q = 0;
      return;
    }

  oldheap = svm_push_data_heap (am->vlib_rp);
  clib_mem_free (rv);
  svm_pop_heap (oldheap);
}

void
vl_set_memory_root_path (char *name)
{
  api_main_t *am = &api_main;

  am->root_path = name;
}

void
vl_set_memory_uid (int uid)
{
  api_main_t *am = &api_main;

  am->api_uid = uid;
}

void
vl_set_memory_gid (int gid)
{
  api_main_t *am = &api_main;

  am->api_gid = gid;
}

int
vl_map_shmem (char *region_name, int is_vlib)
{
  svm_map_region_args_t _a, *a = &_a;
  svm_region_t *vlib_rp, *root_rp;
  void *oldheap;
  vl_shmem_hdr_t *shmem_hdr = 0;
  api_main_t *am = &api_main;
  int i;
  struct timespec ts, tsrem;

  if (is_vlib == 0)
    svm_region_init_chroot (am->root_path);

  memset (a, 0, sizeof (*a));

  a->name = region_name;
  a->size = 16 << 20;
  a->flags = SVM_FLAGS_MHEAP;
  a->uid = am->api_uid;
  a->gid = am->api_gid;

  vlib_rp = svm_region_find_or_create (a);

  if (vlib_rp == 0)
    return (-2);

  pthread_mutex_lock (&vlib_rp->mutex);
  /* Has someone else set up the shared-memory variable table? */
  if (vlib_rp->user_ctx)
    {
      am->shmem_hdr = (void *) vlib_rp->user_ctx;
      am->our_pid = getpid ();
      if (is_vlib)
	{
	  unix_shared_memory_queue_t *q;
	  uword old_msg;
	  /*
	   * application restart. Reset cached pids, API message
	   * rings, list of clients; otherwise, various things
	   * fail. (e.g. queue non-empty notification)
	   */

	  /* ghosts keep the region from disappearing properly */
	  svm_client_scan_this_region_nolock (vlib_rp);
	  am->shmem_hdr->application_restarts++;
	  q = am->shmem_hdr->vl_input_queue;
	  am->shmem_hdr->vl_pid = getpid ();
	  q->consumer_pid = am->shmem_hdr->vl_pid;
	  /* Drain the input queue, freeing msgs */
	  for (i = 0; i < 10; i++)
	    {
	      if (pthread_mutex_trylock (&q->mutex) == 0)
		{
		  pthread_mutex_unlock (&q->mutex);
		  goto mutex_ok;
		}
	      ts.tv_sec = 0;
	      ts.tv_nsec = 10000 * 1000;	/* 10 ms */
	      while (nanosleep (&ts, &tsrem) < 0)
		ts = tsrem;
	    }
	  /* Mutex buggered, "fix" it */
	  memset (&q->mutex, 0, sizeof (q->mutex));
	  clib_warning ("forcibly release main input queue mutex");

	mutex_ok:
	  am->vlib_rp = vlib_rp;
	  while (unix_shared_memory_queue_sub (q,
					       (u8 *) & old_msg,
					       1 /* nowait */ )
		 != -2 /* queue underflow */ )
	    {
	      vl_msg_api_free_nolock ((void *) old_msg);
	      am->shmem_hdr->restart_reclaims++;
	    }
	  pthread_mutex_unlock (&vlib_rp->mutex);
	  root_rp = svm_get_root_rp ();
	  ASSERT (root_rp);
	  /* Clean up the root region client list */
	  pthread_mutex_lock (&root_rp->mutex);
	  svm_client_scan_this_region_nolock (root_rp);
	  pthread_mutex_unlock (&root_rp->mutex);
	}
      else
	{
	  pthread_mutex_unlock (&vlib_rp->mutex);
	}
      am->vlib_rp = vlib_rp;
      vec_add1 (am->mapped_shmem_regions, vlib_rp);
      return 0;
    }
  /* Clients simply have to wait... */
  if (!is_vlib)
    {
      pthread_mutex_unlock (&vlib_rp->mutex);

      /* Wait up to 100 seconds... */
      for (i = 0; i < 10000; i++)
	{
	  ts.tv_sec = 0;
	  ts.tv_nsec = 10000 * 1000;	/* 10 ms */
	  while (nanosleep (&ts, &tsrem) < 0)
	    ts = tsrem;
	  if (vlib_rp->user_ctx)
	    goto ready;
	}
      /* Clean up and leave... */
      svm_region_unmap (vlib_rp);
      clib_warning ("region init fail");
      return (-2);

    ready:
      am->shmem_hdr = (void *) vlib_rp->user_ctx;
      am->our_pid = getpid ();
      am->vlib_rp = vlib_rp;
      vec_add1 (am->mapped_shmem_regions, vlib_rp);
      return 0;
    }

  /* Nope, it's our problem... */

  oldheap = svm_push_data_heap (vlib_rp);

  vec_validate (shmem_hdr, 0);
  shmem_hdr->version = VL_SHM_VERSION;

  /* vlib main input queue */
  shmem_hdr->vl_input_queue =
    unix_shared_memory_queue_init (1024, sizeof (uword), getpid (),
				   am->vlib_signal);

  /* Set up the msg ring allocator */
#define _(sz,n)                                                 \
    do {                                                        \
        ring_alloc_t _rp;                                       \
        _rp.rp = unix_shared_memory_queue_init ((n), (sz), 0, 0); \
        _rp.size = (sz);                                        \
        _rp.nitems = n;                                         \
        _rp.hits = 0;                                           \
        _rp.misses = 0;                                         \
        vec_add1(shmem_hdr->vl_rings, _rp);                     \
    } while (0);

  foreach_vl_aring_size;
#undef _

#define _(sz,n)                                                 \
    do {                                                        \
        ring_alloc_t _rp;                                       \
        _rp.rp = unix_shared_memory_queue_init ((n), (sz), 0, 0); \
        _rp.size = (sz);                                        \
        _rp.nitems = n;                                         \
        _rp.hits = 0;                                           \
        _rp.misses = 0;                                         \
        vec_add1(shmem_hdr->client_rings, _rp);                 \
    } while (0);

  foreach_clnt_aring_size;
#undef _

  am->shmem_hdr = shmem_hdr;
  am->vlib_rp = vlib_rp;
  am->our_pid = getpid ();
  if (is_vlib)
    am->shmem_hdr->vl_pid = am->our_pid;

  svm_pop_heap (oldheap);

  /*
   * After absolutely everything that a client might see is set up,
   * declare the shmem region valid
   */
  vlib_rp->user_ctx = shmem_hdr;

  pthread_mutex_unlock (&vlib_rp->mutex);
  vec_add1 (am->mapped_shmem_regions, vlib_rp);
  return 0;
}

void
vl_register_mapped_shmem_region (svm_region_t * rp)
{
  api_main_t *am = &api_main;

  vec_add1 (am->mapped_shmem_regions, rp);
}

void
vl_unmap_shmem (void)
{
  svm_region_t *rp;
  int i;
  api_main_t *am = &api_main;

  if (!svm_get_root_rp ())
    return;

  for (i = 0; i < vec_len (am->mapped_shmem_regions); i++)
    {
      rp = am->mapped_shmem_regions[i];
      svm_region_unmap (rp);
    }

  vec_free (am->mapped_shmem_regions);
  am->shmem_hdr = 0;

  svm_region_exit ();
  /* $$$ more careful cleanup, valgrind run... */
  vec_free (am->msg_handlers);
  vec_free (am->msg_endian_handlers);
  vec_free (am->msg_print_handlers);
}

void
vl_msg_api_send_shmem (unix_shared_memory_queue_t * q, u8 * elem)
{
  api_main_t *am = &api_main;
  uword *trace = (uword *) elem;

  if (am->tx_trace && am->tx_trace->enabled)
    vl_msg_api_trace (am, am->tx_trace, (void *) trace[0]);

  (void) unix_shared_memory_queue_add (q, elem, 0 /* nowait */ );
}

void
vl_msg_api_send_shmem_nolock (unix_shared_memory_queue_t * q, u8 * elem)
{
  api_main_t *am = &api_main;
  uword *trace = (uword *) elem;

  if (am->tx_trace && am->tx_trace->enabled)
    vl_msg_api_trace (am, am->tx_trace, (void *) trace[0]);

  (void) unix_shared_memory_queue_add_nolock (q, elem);
}

static void
vl_api_memclnt_create_reply_t_handler (vl_api_memclnt_create_reply_t * mp)
{
  api_main_t *am = &api_main;
  int rv;

  am->my_client_index = mp->index;
  am->my_registration = (vl_api_registration_t *) (uword) mp->handle;

  rv = ntohl (mp->response);

  if (rv < 0)
    clib_warning ("WARNING: API mismatch detected");
}

void vl_client_add_api_signatures (vl_api_memclnt_create_t * mp)
  __attribute__ ((weak));

void
vl_client_add_api_signatures (vl_api_memclnt_create_t * mp)
{
  int i;

  for (i = 0; i < ARRAY_LEN (mp->api_versions); i++)
    mp->api_versions[i] = 0;
}

int
vl_client_connect (char *name, int ctx_quota, int input_queue_size)
{
  svm_region_t *svm;
  vl_api_memclnt_create_t *mp;
  vl_api_memclnt_create_reply_t *rp;
  unix_shared_memory_queue_t *vl_input_queue;
  vl_shmem_hdr_t *shmem_hdr;
  int rv = 0;
  void *oldheap;
  api_main_t *am = &api_main;

  if (am->my_registration)
    {
      clib_warning ("client %s already connected...", name);
      return -1;
    }

  if (am->vlib_rp == 0)
    {
      clib_warning ("am->vlib_rp NULL");
      return -1;
    }

  svm = am->vlib_rp;
  shmem_hdr = am->shmem_hdr;

  if (shmem_hdr == 0 || shmem_hdr->vl_input_queue == 0)
    {
      clib_warning ("shmem_hdr / input queue NULL");
      return -1;
    }

  pthread_mutex_lock (&svm->mutex);
  oldheap = svm_push_data_heap (svm);
  vl_input_queue =
    unix_shared_memory_queue_init (input_queue_size, sizeof (uword),
				   getpid (), 0);
  pthread_mutex_unlock (&svm->mutex);
  svm_pop_heap (oldheap);

  am->my_client_index = ~0;
  am->my_registration = 0;
  am->vl_input_queue = vl_input_queue;

  mp = vl_msg_api_alloc (sizeof (vl_api_memclnt_create_t));
  memset (mp, 0, sizeof (*mp));
  mp->_vl_msg_id = ntohs (VL_API_MEMCLNT_CREATE);
  mp->ctx_quota = ctx_quota;
  mp->input_queue = (uword) vl_input_queue;
  strncpy ((char *) mp->name, name, sizeof (mp->name) - 1);

  vl_client_add_api_signatures (mp);

  vl_msg_api_send_shmem (shmem_hdr->vl_input_queue, (u8 *) & mp);

  while (1)
    {
      int qstatus;
      struct timespec ts, tsrem;
      int i;

      /* Wait up to 10 seconds */
      for (i = 0; i < 1000; i++)
	{
	  qstatus = unix_shared_memory_queue_sub (vl_input_queue, (u8 *) & rp,
						  1 /* nowait */ );
	  if (qstatus == 0)
	    goto read_one_msg;
	  ts.tv_sec = 0;
	  ts.tv_nsec = 10000 * 1000;	/* 10 ms */
	  while (nanosleep (&ts, &tsrem) < 0)
	    ts = tsrem;
	}
      /* Timeout... */
      clib_warning ("memclnt_create_reply timeout");
      return -1;

    read_one_msg:
      if (ntohs (rp->_vl_msg_id) != VL_API_MEMCLNT_CREATE_REPLY)
	{
	  clib_warning ("unexpected reply: id %d", ntohs (rp->_vl_msg_id));
	  continue;
	}
      rv = clib_net_to_host_u32 (rp->response);

      vl_msg_api_handler ((void *) rp);
      break;
    }
  return (rv);
}

static void
vl_api_memclnt_delete_reply_t_handler (vl_api_memclnt_delete_reply_t * mp)
{
  void *oldheap;
  api_main_t *am = &api_main;

  pthread_mutex_lock (&am->vlib_rp->mutex);
  oldheap = svm_push_data_heap (am->vlib_rp);
  unix_shared_memory_queue_free (am->vl_input_queue);
  pthread_mutex_unlock (&am->vlib_rp->mutex);
  svm_pop_heap (oldheap);

  am->my_client_index = ~0;
  am->my_registration = 0;
  am->vl_input_queue = 0;
}

void
vl_client_disconnect (void)
{
  vl_api_memclnt_delete_t *mp;
  vl_api_memclnt_delete_reply_t *rp;
  unix_shared_memory_queue_t *vl_input_queue;
  vl_shmem_hdr_t *shmem_hdr;
  time_t begin;
  api_main_t *am = &api_main;

  ASSERT (am->vlib_rp);
  shmem_hdr = am->shmem_hdr;
  ASSERT (shmem_hdr && shmem_hdr->vl_input_queue);

  vl_input_queue = am->vl_input_queue;

  mp = vl_msg_api_alloc (sizeof (vl_api_memclnt_delete_t));
  memset (mp, 0, sizeof (*mp));
  mp->_vl_msg_id = ntohs (VL_API_MEMCLNT_DELETE);
  mp->index = am->my_client_index;
  mp->handle = (uword) am->my_registration;

  vl_msg_api_send_shmem (shmem_hdr->vl_input_queue, (u8 *) & mp);

  /*
   * Have to be careful here, in case the client is disconnecting
   * because e.g. the vlib process died, or is unresponsive.
   */

  begin = time (0);
  while (1)
    {
      time_t now;

      now = time (0);

      if (now >= (begin + 2))
	{
	  clib_warning ("peer unresponsive, give up");
	  am->my_client_index = ~0;
	  am->my_registration = 0;
	  am->shmem_hdr = 0;
	  break;
	}
      if (unix_shared_memory_queue_sub (vl_input_queue, (u8 *) & rp, 1) < 0)
	continue;

      /* drain the queue */
      if (ntohs (rp->_vl_msg_id) != VL_API_MEMCLNT_DELETE_REPLY)
	{
	  vl_msg_api_handler ((void *) rp);
	  continue;
	}
      vl_msg_api_handler ((void *) rp);
      break;
    }
}

static inline vl_api_registration_t *
vl_api_client_index_to_registration_internal (u32 handle)
{
  vl_api_registration_t **regpp;
  vl_api_registration_t *regp;
  api_main_t *am = &api_main;
  u32 index;

  index = vl_msg_api_handle_get_index (handle);
  if ((am->shmem_hdr->application_restarts & VL_API_EPOCH_MASK)
      != vl_msg_api_handle_get_epoch (handle))
    {
      vl_msg_api_increment_missing_client_counter ();
      return 0;
    }

  regpp = am->vl_clients + index;

  if (pool_is_free (am->vl_clients, regpp))
    {
      vl_msg_api_increment_missing_client_counter ();
      return 0;
    }
  regp = *regpp;
  return (regp);
}

vl_api_registration_t *
vl_api_client_index_to_registration (u32 index)
{
  return (vl_api_client_index_to_registration_internal (index));
}

unix_shared_memory_queue_t *
vl_api_client_index_to_input_queue (u32 index)
{
  vl_api_registration_t *regp;

  regp = vl_api_client_index_to_registration_internal (index);
  if (!regp)
    return 0;
  return (regp->vl_input_queue);
}

#define foreach_api_client_msg                  \
_(MEMCLNT_CREATE_REPLY, memclnt_create_reply)   \
_(MEMCLNT_DELETE_REPLY, memclnt_delete_reply)

int
vl_client_api_map (char *region_name)
{
  int rv;

  if ((rv = vl_map_shmem (region_name, 0 /* is_vlib */ )) < 0)
    {
      return rv;
    }

#define _(N,n)                                                          \
    vl_msg_api_set_handlers(VL_API_##N, 0 /* name */,                   \
                           vl_api_##n##_t_handler,                      \
                           0/* cleanup */, 0/* endian */, 0/* print */, \
                           sizeof(vl_api_##n##_t), 1);
  foreach_api_client_msg;
#undef _
  return 0;
}

void
vl_client_api_unmap (void)
{
  vl_unmap_shmem ();
}

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