ioam_cache_tunnel_select_node.c

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/*
 * 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.
 */
/*
 * ioam_cache_tunnel_select_node.c
 * This file implements anycast server selection using ioam data
 * attached to anycast service selection.
 * Anycast service is reachable via multiple servers reachable
 * over SR tunnels.
 * Works with TCP Anycast application.
 * Cache entry is created when TCP SYN is received for anycast destination.
 * Response TCP SYN ACKs for anycast service is compared and selected
 * response is forwarded.
 * The functionality is introduced via graph nodes that are hooked into
 * vnet graph via classifier configs like below:
 *
 * Enable anycast service selection:
 * set ioam ip6 sr-tunnel-select oneway
 *
 * Enable following classifier on the anycast service client facing interface
 * e.g. anycast service is db06::06 then:
 * classify session acl-hit-next ip6-node ip6-add-syn-hop-by-hop table-index 0 match l3
 * ip6 dst db06::06 ioam-encap anycast
 *
 * Enable following classifier on the interfaces facing the server of anycast service:
 * classify session acl-hit-next ip6-node ip6-lookup table-index 0 match l3
 *            ip6 src db06::06 ioam-decap anycast
 *
 */
#include <vlib/vlib.h>
#include <vnet/vnet.h>
#include <vppinfra/error.h>
#include <vnet/ip/ip.h>
#include <vnet/srv6/sr.h>
#include <ioam/ip6/ioam_cache.h>
#include <vnet/ip/ip6_hop_by_hop.h>
#include <vnet/ip/ip6_hop_by_hop_packet.h>
#include <vnet/ip/ip6_inlines.h>
 
typedef struct
{
  u32 next_index;
  u32 flow_label;
} cache_ts_trace_t;
 
/* packet trace format function */
static u8 *
format_cache_ts_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 *);
  cache_ts_trace_t *t = va_arg (*args, cache_ts_trace_t *);
 
  s = format (s, "CACHE: flow_label %d, next index %d",
              t->flow_label, t->next_index);
  return s;
}
 
#define foreach_cache_ts_error \
_(RECORDED, "ip6 iOAM headers cached")
 
typedef enum
{
#define _(sym,str) CACHE_TS_ERROR_##sym,
  foreach_cache_ts_error
#undef _
    CACHE_TS_N_ERROR,
} cache_ts_error_t;
 
static char *cache_ts_error_strings[] = {
#define _(sym,string) string,
  foreach_cache_ts_error
#undef _
};
 
typedef enum
{
  IOAM_CACHE_TS_NEXT_POP_HBYH,
  IOAM_CACHE_TS_ERROR_NEXT_DROP,
  IOAM_CACHE_TS_N_NEXT,
} cache_ts_next_t;
 
static uword
ip6_ioam_cache_ts_node_fn (vlib_main_t * vm,
                           vlib_node_runtime_t * node, vlib_frame_t * frame)
{
  ioam_cache_main_t *cm = &ioam_cache_main;
  u32 n_left_from, *from, *to_next;
  cache_ts_next_t next_index;
  u32 recorded = 0;
 
  from = vlib_frame_vector_args (frame);
  n_left_from = frame->n_vectors;
  next_index = node->cached_next_index;
 
  while (n_left_from > 0)
    {
      u32 n_left_to_next;
 
      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
      // TODO: dual loop
      while (n_left_from > 0 && n_left_to_next > 0)
        {
          u32 bi0;
          vlib_buffer_t *p0;
          u32 next0 = IOAM_CACHE_TS_NEXT_POP_HBYH;
          ip6_header_t *ip0;
          ip6_hop_by_hop_header_t *hbh0, *hbh_cmp;
          tcp_header_t *tcp0;
          u32 tcp_offset0;
          u32 cache_ts_index = 0;
          u8 cache_thread_id = 0;
          int result = 0;
          int skip = 0;
 
          bi0 = from[0];
          from += 1;
          n_left_from -= 1;
 
          p0 = vlib_get_buffer (vm, bi0);
          ip0 = vlib_buffer_get_current (p0);
          if (IP_PROTOCOL_TCP ==
              ip6_locate_header (p0, ip0, IP_PROTOCOL_TCP, &tcp_offset0))
            {
              tcp0 = (tcp_header_t *) ((u8 *) ip0 + tcp_offset0);
              if ((tcp0->flags & TCP_FLAG_SYN) == TCP_FLAG_SYN &&
                  (tcp0->flags & TCP_FLAG_ACK) == TCP_FLAG_ACK)
                {
                  /* Look up and compare */
                  hbh0 = (ip6_hop_by_hop_header_t *) (ip0 + 1);
 
                  if (0 == ioam_cache_ts_lookup (ip0,
                                                 hbh0->protocol,
                                                 clib_net_to_host_u16
                                                 (tcp0->src_port),
                                                 clib_net_to_host_u16
                                                 (tcp0->dst_port),
                                                 clib_net_to_host_u32
                                                 (tcp0->ack_number), &hbh_cmp,
                                                 &cache_ts_index,
                                                 &cache_thread_id, 1))
                    {
                      /* response seen */
                      result = -1;
                      if (hbh_cmp)
                        result =
                          ip6_ioam_analyse_compare_path_delay (hbh0, hbh_cmp,
                                                               cm->criteria_oneway);
                      if (result >= 0)
                        {
                          /* current syn/ack is worse than the earlier: Drop */
                          next0 = IOAM_CACHE_TS_ERROR_NEXT_DROP;
                          /* Check if all responses are received or time has exceeded
                             send cached response if yes */
                          ioam_cache_ts_check_and_send (cache_thread_id,
                                                        cache_ts_index);
                        }
                      else
                        {
                          /* Update cache with this buffer */
                          /* If successfully updated then skip sending it */
                          if (0 ==
                              (result =
                               ioam_cache_ts_update (cache_thread_id,
                                                     cache_ts_index, bi0,
                                                     hbh0)))
                            {
                              skip = 1;
                            }
                          else
                            next0 = IOAM_CACHE_TS_ERROR_NEXT_DROP;
                        }
                    }
                  else
                    {
                      next0 = IOAM_CACHE_TS_ERROR_NEXT_DROP;
                    }
                }
              else if ((tcp0->flags & TCP_FLAG_RST) == TCP_FLAG_RST)
                {
                  /* Look up and compare */
                  hbh0 = (ip6_hop_by_hop_header_t *) (ip0 + 1);
                  if (0 == ioam_cache_ts_lookup (ip0, hbh0->protocol, clib_net_to_host_u16 (tcp0->src_port), clib_net_to_host_u16 (tcp0->dst_port), clib_net_to_host_u32 (tcp0->ack_number), &hbh_cmp, &cache_ts_index, &cache_thread_id, 1))   //response seen
                    {
                      next0 = IOAM_CACHE_TS_ERROR_NEXT_DROP;
                      if (hbh_cmp)
                        ioam_cache_ts_check_and_send (cache_thread_id,
                                                      cache_ts_index);
                    }
 
                }
            }
          if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
            {
              if (p0->flags & VLIB_BUFFER_IS_TRACED)
                {
                  cache_ts_trace_t *t =
                    vlib_add_trace (vm, node, p0, sizeof (*t));
                  t->flow_label =
                    clib_net_to_host_u32
                    (ip0->ip_version_traffic_class_and_flow_label);
                  t->next_index = next0;
                }
            }
          /* verify speculative enqueue, maybe switch current next frame */
          if (!skip)
            {
              to_next[0] = bi0;
              to_next += 1;
              n_left_to_next -= 1;
              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);
    }
  vlib_node_increment_counter (vm, ioam_cache_ts_node.index,
                               CACHE_TS_ERROR_RECORDED, recorded);
  return frame->n_vectors;
}
 
/*
 * Node for IP6 iOAM header cache
 */
/* *INDENT-OFF* */
VLIB_REGISTER_NODE (ioam_cache_ts_node) =
{
  .function = ip6_ioam_cache_ts_node_fn,
  .name = "ip6-ioam-tunnel-select",
  .vector_size = sizeof (u32),
  .format_trace = format_cache_ts_trace,
  .type = VLIB_NODE_TYPE_INTERNAL,
  .n_errors = ARRAY_LEN (cache_ts_error_strings),
  .error_strings = cache_ts_error_strings,
  .n_next_nodes = IOAM_CACHE_TS_N_NEXT,
  /* edit / add dispositions here */
  .next_nodes =
  {
    [IOAM_CACHE_TS_NEXT_POP_HBYH] = "ip6-pop-hop-by-hop",
    [IOAM_CACHE_TS_ERROR_NEXT_DROP] = "error-drop",
  },
};
/* *INDENT-ON* */
 
typedef struct
{
  u32 next_index;
} ip6_reset_ts_hbh_trace_t;
 
/* packet trace format function */
static u8 *
format_ip6_reset_ts_hbh_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 *);
  ip6_reset_ts_hbh_trace_t *t = va_arg (*args,
                                        ip6_reset_ts_hbh_trace_t *);
 
  s =
    format (s, "IP6_IOAM_RESET_TUNNEL_SELECT_HBH: next index %d",
            t->next_index);
  return s;
}
 
#define foreach_ip6_reset_ts_hbh_error \
_(PROCESSED, "iOAM Syn/Ack Pkts processed") \
_(SAVED, "iOAM Syn Pkts state saved") \
_(REMOVED, "iOAM Syn/Ack Pkts state removed")
 
typedef enum
{
#define _(sym,str) IP6_RESET_TS_HBH_ERROR_##sym,
  foreach_ip6_reset_ts_hbh_error
#undef _
    IP6_RESET_TS_HBH_N_ERROR,
} ip6_reset_ts_hbh_error_t;
 
static char *ip6_reset_ts_hbh_error_strings[] = {
#define _(sym,string) string,
  foreach_ip6_reset_ts_hbh_error
#undef _
};
 
#define foreach_ip6_ioam_cache_ts_input_next    \
  _(IP6_LOOKUP, "ip6-lookup")                   \
  _(DROP, "error-drop")
 
typedef enum
{
#define _(s,n) IP6_IOAM_CACHE_TS_INPUT_NEXT_##s,
  foreach_ip6_ioam_cache_ts_input_next
#undef _
    IP6_IOAM_CACHE_TS_INPUT_N_NEXT,
} ip6_ioam_cache_ts_input_next_t;
 
 
VLIB_NODE_FN (ip6_reset_ts_hbh_node) (vlib_main_t * vm,
                                      vlib_node_runtime_t * node,
                                      vlib_frame_t * frame)
{
  ioam_cache_main_t *cm = &ioam_cache_main;
  u32 n_left_from, *from, *to_next;
  ip_lookup_next_t next_index;
  u32 processed = 0, cache_ts_added = 0;
  u64 now;
  u8 *rewrite = cm->rewrite;
  u32 rewrite_length = vec_len (rewrite);
  ioam_e2e_cache_option_t *e2e = 0;
  u8 no_of_responses = cm->wait_for_responses;
 
  from = vlib_frame_vector_args (frame);
  n_left_from = frame->n_vectors;
  next_index = node->cached_next_index;
 
  while (n_left_from > 0)
    {
      u32 n_left_to_next;
 
      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 
      now = vlib_time_now (vm);
      while (n_left_from >= 4 && n_left_to_next >= 2)
        {
          u32 bi0, bi1;
          vlib_buffer_t *b0, *b1;
          u32 next0, next1;
          ip6_header_t *ip0, *ip1;
          tcp_header_t *tcp0, *tcp1;
          u32 tcp_offset0, tcp_offset1;
          ip6_hop_by_hop_header_t *hbh0, *hbh1;
          u64 *copy_src0, *copy_dst0, *copy_src1, *copy_dst1;
          u16 new_l0, new_l1;
          u32 pool_index0 = 0, pool_index1 = 0;
 
          next0 = next1 = IP6_IOAM_CACHE_TS_INPUT_NEXT_IP6_LOOKUP;
          /* Prefetch next iteration. */
          {
            vlib_buffer_t *p2, *p3;
 
            p2 = vlib_get_buffer (vm, from[2]);
            p3 = vlib_get_buffer (vm, from[3]);
 
            vlib_prefetch_buffer_header (p2, LOAD);
            vlib_prefetch_buffer_header (p3, LOAD);
            CLIB_PREFETCH (p2->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
            CLIB_PREFETCH (p3->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
          }
 
 
          /* speculatively enqueue b0 to the current next frame */
          to_next[0] = bi0 = from[0];
          to_next[1] = bi1 = from[1];
          from += 2;
          to_next += 2;
          n_left_from -= 2;
          n_left_to_next -= 2;
 
          b0 = vlib_get_buffer (vm, bi0);
          b1 = vlib_get_buffer (vm, bi1);
 
          ip0 = vlib_buffer_get_current (b0);
          ip1 = vlib_buffer_get_current (b1);
 
          if (IP_PROTOCOL_TCP !=
              ip6_locate_header (b0, ip0, IP_PROTOCOL_TCP, &tcp_offset0))
            {
              goto NEXT00;
            }
          tcp0 = (tcp_header_t *) ((u8 *) ip0 + tcp_offset0);
          if ((tcp0->flags & TCP_FLAG_SYN) == TCP_FLAG_SYN &&
              (tcp0->flags & TCP_FLAG_ACK) == 0)
            {
              if (no_of_responses > 0)
                {
                  /* Create TS select entry */
                  if (0 == ioam_cache_ts_add (ip0,
                                              clib_net_to_host_u16
                                              (tcp0->src_port),
                                              clib_net_to_host_u16
                                              (tcp0->dst_port),
                                              clib_net_to_host_u32
                                              (tcp0->seq_number) + 1,
                                              no_of_responses, now,
                                              vm->thread_index, &pool_index0))
                    {
                      cache_ts_added++;
                    }
                }
              copy_dst0 = (u64 *) (((u8 *) ip0) - rewrite_length);
              copy_src0 = (u64 *) ip0;
 
              copy_dst0[0] = copy_src0[0];
              copy_dst0[1] = copy_src0[1];
              copy_dst0[2] = copy_src0[2];
              copy_dst0[3] = copy_src0[3];
              copy_dst0[4] = copy_src0[4];
 
              vlib_buffer_advance (b0, -(word) rewrite_length);
              ip0 = vlib_buffer_get_current (b0);
 
              hbh0 = (ip6_hop_by_hop_header_t *) (ip0 + 1);
              /* $$$ tune, rewrite_length is a multiple of 8 */
              clib_memcpy_fast (hbh0, rewrite, rewrite_length);
              e2e =
                (ioam_e2e_cache_option_t *) ((u8 *) hbh0 +
                                             cm->rewrite_pool_index_offset);
              e2e->pool_id = (u8) vm->thread_index;
              e2e->pool_index = pool_index0;
              ioam_e2e_id_rewrite_handler ((ioam_e2e_id_option_t *)
                                           ((u8 *) e2e +
                                            sizeof (ioam_e2e_cache_option_t)),
                                           &cm->sr_localsid_ts);
              /* Patch the protocol chain, insert the h-b-h (type 0) header */
              hbh0->protocol = ip0->protocol;
              ip0->protocol = 0;
              new_l0 =
                clib_net_to_host_u16 (ip0->payload_length) + rewrite_length;
              ip0->payload_length = clib_host_to_net_u16 (new_l0);
              processed++;
            }
 
        NEXT00:
          if (IP_PROTOCOL_TCP !=
              ip6_locate_header (b1, ip1, IP_PROTOCOL_TCP, &tcp_offset1))
            {
              goto TRACE00;
            }
          tcp1 = (tcp_header_t *) ((u8 *) ip1 + tcp_offset1);
          if ((tcp1->flags & TCP_FLAG_SYN) == TCP_FLAG_SYN &&
              (tcp1->flags & TCP_FLAG_ACK) == 0)
            {
              if (no_of_responses > 0)
                {
                  /* Create TS select entry */
                  if (0 == ioam_cache_ts_add (ip1,
                                              clib_net_to_host_u16
                                              (tcp1->src_port),
                                              clib_net_to_host_u16
                                              (tcp1->dst_port),
                                              clib_net_to_host_u32
                                              (tcp1->seq_number) + 1,
                                              no_of_responses, now,
                                              vm->thread_index, &pool_index1))
                    {
                      cache_ts_added++;
                    }
                }
 
              copy_dst1 = (u64 *) (((u8 *) ip1) - rewrite_length);
              copy_src1 = (u64 *) ip1;
 
              copy_dst1[0] = copy_src1[0];
              copy_dst1[1] = copy_src1[1];
              copy_dst1[2] = copy_src1[2];
              copy_dst1[3] = copy_src1[3];
              copy_dst1[4] = copy_src1[4];
 
              vlib_buffer_advance (b1, -(word) rewrite_length);
              ip1 = vlib_buffer_get_current (b1);
 
              hbh1 = (ip6_hop_by_hop_header_t *) (ip1 + 1);
              /* $$$ tune, rewrite_length is a multiple of 8 */
              clib_memcpy_fast (hbh1, rewrite, rewrite_length);
              e2e =
                (ioam_e2e_cache_option_t *) ((u8 *) hbh1 +
                                             cm->rewrite_pool_index_offset);
              e2e->pool_id = (u8) vm->thread_index;
              e2e->pool_index = pool_index1;
              ioam_e2e_id_rewrite_handler ((ioam_e2e_id_option_t *)
                                           ((u8 *) e2e +
                                            sizeof (ioam_e2e_cache_option_t)),
                                           &cm->sr_localsid_ts);
              /* Patch the protocol chain, insert the h-b-h (type 0) header */
              hbh1->protocol = ip1->protocol;
              ip1->protocol = 0;
              new_l1 =
                clib_net_to_host_u16 (ip1->payload_length) + rewrite_length;
              ip1->payload_length = clib_host_to_net_u16 (new_l1);
              processed++;
            }
 
        TRACE00:
          if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
            {
              if (b0->flags & VLIB_BUFFER_IS_TRACED)
                {
                  ip6_reset_ts_hbh_trace_t *t =
                    vlib_add_trace (vm, node, b0, sizeof (*t));
                  t->next_index = next0;
                }
              if (b1->flags & VLIB_BUFFER_IS_TRACED)
                {
                  ip6_reset_ts_hbh_trace_t *t =
                    vlib_add_trace (vm, node, b1, sizeof (*t));
                  t->next_index = next1;
                }
 
            }
 
          /* verify speculative enqueue, maybe switch current next frame */
          vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
                                           to_next, n_left_to_next,
                                           bi0, bi1, next0, next1);
        }
      while (n_left_from > 0 && n_left_to_next > 0)
        {
          u32 bi0;
          vlib_buffer_t *b0;
          u32 next0;
          ip6_header_t *ip0;
          tcp_header_t *tcp0;
          u32 tcp_offset0;
          ip6_hop_by_hop_header_t *hbh0;
          u64 *copy_src0, *copy_dst0;
          u16 new_l0;
          u32 pool_index0 = 0;
 
          next0 = IP6_IOAM_CACHE_TS_INPUT_NEXT_IP6_LOOKUP;
          /* speculatively enqueue b0 to the current next frame */
          bi0 = from[0];
          to_next[0] = bi0;
          from += 1;
          to_next += 1;
          n_left_from -= 1;
          n_left_to_next -= 1;
 
          b0 = vlib_get_buffer (vm, bi0);
 
          ip0 = vlib_buffer_get_current (b0);
          if (IP_PROTOCOL_TCP !=
              ip6_locate_header (b0, ip0, IP_PROTOCOL_TCP, &tcp_offset0))
            {
              goto TRACE0;
            }
          tcp0 = (tcp_header_t *) ((u8 *) ip0 + tcp_offset0);
          if ((tcp0->flags & TCP_FLAG_SYN) == TCP_FLAG_SYN &&
              (tcp0->flags & TCP_FLAG_ACK) == 0)
            {
              if (no_of_responses > 0)
                {
                  /* Create TS select entry */
                  if (0 == ioam_cache_ts_add (ip0,
                                              clib_net_to_host_u16
                                              (tcp0->src_port),
                                              clib_net_to_host_u16
                                              (tcp0->dst_port),
                                              clib_net_to_host_u32
                                              (tcp0->seq_number) + 1,
                                              no_of_responses, now,
                                              vm->thread_index, &pool_index0))
                    {
                      cache_ts_added++;
                    }
                }
              copy_dst0 = (u64 *) (((u8 *) ip0) - rewrite_length);
              copy_src0 = (u64 *) ip0;
 
              copy_dst0[0] = copy_src0[0];
              copy_dst0[1] = copy_src0[1];
              copy_dst0[2] = copy_src0[2];
              copy_dst0[3] = copy_src0[3];
              copy_dst0[4] = copy_src0[4];
 
              vlib_buffer_advance (b0, -(word) rewrite_length);
              ip0 = vlib_buffer_get_current (b0);
 
              hbh0 = (ip6_hop_by_hop_header_t *) (ip0 + 1);
              /* $$$ tune, rewrite_length is a multiple of 8 */
              clib_memcpy_fast (hbh0, rewrite, rewrite_length);
              e2e =
                (ioam_e2e_cache_option_t *) ((u8 *) hbh0 +
                                             cm->rewrite_pool_index_offset);
              e2e->pool_id = (u8) vm->thread_index;
              e2e->pool_index = pool_index0;
              ioam_e2e_id_rewrite_handler ((ioam_e2e_id_option_t *)
                                           ((u8 *) e2e +
                                            sizeof (ioam_e2e_cache_option_t)),
                                           &cm->sr_localsid_ts);
              /* Patch the protocol chain, insert the h-b-h (type 0) header */
              hbh0->protocol = ip0->protocol;
              ip0->protocol = 0;
              new_l0 =
                clib_net_to_host_u16 (ip0->payload_length) + rewrite_length;
              ip0->payload_length = clib_host_to_net_u16 (new_l0);
              processed++;
            }
        TRACE0:
          if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
                             && (b0->flags & VLIB_BUFFER_IS_TRACED)))
            {
              ip6_reset_ts_hbh_trace_t *t =
                vlib_add_trace (vm, node, b0, sizeof (*t));
              t->next_index = next0;
            }
 
          /* verify speculative enqueue, maybe switch current next frame */
          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);
    }
 
  vlib_node_increment_counter (vm, cm->ip6_reset_ts_hbh_node_index,
                               IP6_RESET_TS_HBH_ERROR_PROCESSED, processed);
  vlib_node_increment_counter (vm, cm->ip6_reset_ts_hbh_node_index,
                               IP6_RESET_TS_HBH_ERROR_SAVED, cache_ts_added);
 
  return frame->n_vectors;
}
 
/* *INDENT-OFF* */
VLIB_REGISTER_NODE (ip6_reset_ts_hbh_node) =
{
  .name = "ip6-add-syn-hop-by-hop",
  .vector_size = sizeof (u32),
  .format_trace = format_ip6_reset_ts_hbh_trace,
  .type = VLIB_NODE_TYPE_INTERNAL,
  .n_errors = ARRAY_LEN (ip6_reset_ts_hbh_error_strings),
  .error_strings =  ip6_reset_ts_hbh_error_strings,
  /* See ip/lookup.h */
  .n_next_nodes = IP6_IOAM_CACHE_TS_INPUT_N_NEXT,
  .next_nodes =
  {
#define _(s,n) [IP6_IOAM_CACHE_TS_INPUT_NEXT_##s] = n,
    foreach_ip6_ioam_cache_ts_input_next
#undef _
  },
};
 
/* *INDENT-ON* */
 
#ifndef CLIB_MARCH_VARIANT
vlib_node_registration_t ioam_cache_ts_timer_tick_node;
#endif /* CLIB_MARCH_VARIANT */
 
typedef struct
{
  u32 thread_index;
} ioam_cache_ts_timer_tick_trace_t;
 
/* packet trace format function */
static u8 *
format_ioam_cache_ts_timer_tick_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 *);
  ioam_cache_ts_timer_tick_trace_t *t =
    va_arg (*args, ioam_cache_ts_timer_tick_trace_t *);
 
  s = format (s, "IOAM_CACHE_TS_TIMER_TICK: thread index %d",
              t->thread_index);
  return s;
}
 
#define foreach_ioam_cache_ts_timer_tick_error                 \
  _(TIMER, "Timer events")
 
typedef enum
{
#define _(sym,str) IOAM_CACHE_TS_TIMER_TICK_ERROR_##sym,
  foreach_ioam_cache_ts_timer_tick_error
#undef _
    IOAM_CACHE_TS_TIMER_TICK_N_ERROR,
} ioam_cache_ts_timer_tick_error_t;
 
static char *ioam_cache_ts_timer_tick_error_strings[] = {
#define _(sym,string) string,
  foreach_ioam_cache_ts_timer_tick_error
#undef _
};
 
#ifndef CLIB_MARCH_VARIANT
void
ioam_cache_ts_timer_node_enable (vlib_main_t * vm, u8 enable)
{
  vlib_node_set_state (vm, ioam_cache_ts_timer_tick_node.index,
                       enable ==
                       0 ? VLIB_NODE_STATE_DISABLED :
                       VLIB_NODE_STATE_POLLING);
}
 
void
expired_cache_ts_timer_callback (u32 * expired_timers)
{
  ioam_cache_main_t *cm = &ioam_cache_main;
  int i;
  u32 pool_index;
  u32 thread_index = vlib_get_thread_index ();
  u32 count = 0;
 
  for (i = 0; i < vec_len (expired_timers); i++)
    {
      /* Get pool index and pool id */
      pool_index = expired_timers[i] & 0x0FFFFFFF;
 
      /* Handle expiration */
      ioam_cache_ts_send (thread_index, pool_index);
      count++;
    }
  vlib_node_increment_counter (cm->vlib_main,
                               ioam_cache_ts_timer_tick_node.index,
                               IOAM_CACHE_TS_TIMER_TICK_ERROR_TIMER, count);
}
#endif /* CLIB_MARCH_VARIANT */
 
static uword
ioam_cache_ts_timer_tick_node_fn (vlib_main_t * vm,
                                  vlib_node_runtime_t * node,
                                  vlib_frame_t * f)
{
  ioam_cache_main_t *cm = &ioam_cache_main;
  u32 my_thread_index = vlib_get_thread_index ();
  struct timespec ts, tsrem;
 
  tw_timer_expire_timers_16t_2w_512sl (&cm->timer_wheels[my_thread_index],
                                       vlib_time_now (vm));
  ts.tv_sec = 0;
  ts.tv_nsec = 1000 * 1000 * IOAM_CACHE_TS_TICK;
  while (nanosleep (&ts, &tsrem) < 0)
    {
      ts = tsrem;
    }
 
  return 0;
}
/* *INDENT-OFF* */
VLIB_REGISTER_NODE (ioam_cache_ts_timer_tick_node) = {
  .function = ioam_cache_ts_timer_tick_node_fn,
  .name = "ioam-cache-ts-timer-tick",
  .format_trace = format_ioam_cache_ts_timer_tick_trace,
  .type = VLIB_NODE_TYPE_INPUT,
 
  .n_errors = ARRAY_LEN(ioam_cache_ts_timer_tick_error_strings),
  .error_strings = ioam_cache_ts_timer_tick_error_strings,
 
  .n_next_nodes = 1,
 
  .state = VLIB_NODE_STATE_DISABLED,
 
  /* edit / add dispositions here */
  .next_nodes = {
    [0] = "error-drop",
  },
};
/* *INDENT-ON* */
 
/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */