text: /*
   * Copyright (c) 2015 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 <vnet/ip/ip.h>
  #include <vnet/ethernet/ethernet.h>	/* for ethernet_header_t */
  #include <vnet/classify/vnet_classify.h>
  #include <vnet/dpo/classify_dpo.h>
  
  typedef struct {
    u32 next_index;
    u32 table_index;
    u32 entry_index;
  } ip_classify_trace_t;
  
  /* packet trace format function */
  static u8 * format_ip_classify_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 *);
    ip_classify_trace_t * t = va_arg (*args, ip_classify_trace_t *);
    
    s = format (s, "IP_CLASSIFY: next_index %d, table %d, entry %d",
                t->next_index, t->table_index, t->entry_index);
    return s;
  }
  
  vlib_node_registration_t ip4_classify_node;
  vlib_node_registration_t ip6_classify_node;
  
  #define foreach_ip_classify_error               \
  _(MISS, "Classify misses")                      \
  _(HIT, "Classify hits")                         \
  _(CHAIN_HIT, "Classify hits after chain walk")
  
  typedef enum {
  #define _(sym,str) IP_CLASSIFY_ERROR_##sym,
    foreach_ip_classify_error
  #undef _
    IP_CLASSIFY_N_ERROR,
  } ip_classify_error_t;
  
  static char * ip_classify_error_strings[] = {
  #define _(sym,string) string,
    foreach_ip_classify_error
  #undef _
  };
  
  static inline uword
  ip_classify_inline (vlib_main_t * vm,
                      vlib_node_runtime_t * node,
                      vlib_frame_t * frame, int is_ip4)
  {
    u32 n_left_from, * from, * to_next;
    ip_lookup_next_t next_index;
    vnet_classify_main_t * vcm = &vnet_classify_main;
    f64 now = vlib_time_now (vm);
    u32 hits = 0;
    u32 misses = 0;
    u32 chain_hits = 0;
    u32 n_next;
  
    if (is_ip4) {
      n_next = IP4_LOOKUP_N_NEXT;
    } else {
      n_next = IP6_LOOKUP_N_NEXT;
    }
  
    from = vlib_frame_vector_args (frame);
    n_left_from = frame->n_vectors;
  
    /* First pass: compute hashes */
  
    while (n_left_from > 2)
      {
        vlib_buffer_t * b0, * b1;
        u32 bi0, bi1;
        u8 * h0, * h1;
        u32 cd_index0, cd_index1;
        classify_dpo_t *cd0, * cd1;
        u32 table_index0, table_index1;
        vnet_classify_table_t * t0, * t1;
  
        /* prefetch next iteration */
          {
            vlib_buffer_t * p1, * p2;
            
            p1 = vlib_get_buffer (vm, from[1]);
            p2 = vlib_get_buffer (vm, from[2]);
            
            vlib_prefetch_buffer_header (p1, STORE);
            CLIB_PREFETCH (p1->data, CLIB_CACHE_LINE_BYTES, STORE);
            vlib_prefetch_buffer_header (p2, STORE);
            CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, STORE);
          }
          
        bi0 = from[0];
        b0 = vlib_get_buffer (vm, bi0);
        h0 = (void *)vlib_buffer_get_current(b0) -
                  ethernet_buffer_header_size(b0);
  
        bi1 = from[1];
        b1 = vlib_get_buffer (vm, bi1);
        h1 = (void *)vlib_buffer_get_current(b1) -
                  ethernet_buffer_header_size(b1);
          
        cd_index0 = vnet_buffer (b0)->ip.adj_index[VLIB_TX];
        cd0 = classify_dpo_get(cd_index0);
        table_index0 = cd0->cd_table_index;
  
        cd_index1 = vnet_buffer (b1)->ip.adj_index[VLIB_TX];
        cd1 = classify_dpo_get(cd_index1);
        table_index1 = cd1->cd_table_index;
  
        t0 = pool_elt_at_index (vcm->tables, table_index0);
  
        t1 = pool_elt_at_index (vcm->tables, table_index1);
              
        vnet_buffer(b0)->l2_classify.hash = 
          vnet_classify_hash_packet (t0, (u8 *) h0);
  
        vnet_classify_prefetch_bucket (t0, vnet_buffer(b0)->l2_classify.hash);
  
        vnet_buffer(b1)->l2_classify.hash = 
          vnet_classify_hash_packet (t1, (u8 *) h1);
  
        vnet_classify_prefetch_bucket (t1, vnet_buffer(b1)->l2_classify.hash);
  
        vnet_buffer(b0)->l2_classify.table_index = table_index0;
  
        vnet_buffer(b1)->l2_classify.table_index = table_index1;
  
        from += 2;
        n_left_from -= 2;
      }
  
    while (n_left_from > 0)
      {
        vlib_buffer_t * b0;
        u32 bi0;
        u8 * h0;
        u32 cd_index0;
        classify_dpo_t *cd0;
        u32 table_index0;
        vnet_classify_table_t * t0;
  
        bi0 = from[0];
        b0 = vlib_get_buffer (vm, bi0);
        h0 = (void *)vlib_buffer_get_current(b0) -
                  ethernet_buffer_header_size(b0);
          
        cd_index0 = vnet_buffer (b0)->ip.adj_index[VLIB_TX];
        cd0 = classify_dpo_get(cd_index0);
        table_index0 = cd0->cd_table_index;
  
        t0 = pool_elt_at_index (vcm->tables, table_index0);
        vnet_buffer(b0)->l2_classify.hash = 
          vnet_classify_hash_packet (t0, (u8 *) h0);
  
        vnet_buffer(b0)->l2_classify.table_index = table_index0;
        vnet_classify_prefetch_bucket (t0, vnet_buffer(b0)->l2_classify.hash);
  
        from++;
        n_left_from--;
      }
          
    next_index = node->cached_next_index;
    from = vlib_frame_vector_args (frame);
    n_left_from = frame->n_vectors;
  
    while (n_left_from > 0)
      {
        u32 n_left_to_next;
  
        vlib_get_next_frame (vm, node, next_index,
  			   to_next, n_left_to_next);
  
        /* Not enough load/store slots to dual loop... */
        while (n_left_from > 0 && n_left_to_next > 0)
  	{
            u32 bi0;
  	  vlib_buffer_t * b0;
            u32 next0 = IP_LOOKUP_NEXT_DROP;
            u32 table_index0;
            vnet_classify_table_t * t0;
            vnet_classify_entry_t * e0;
            u64 hash0;
            u8 * h0;
  
            /* Stride 3 seems to work best */
            if (PREDICT_TRUE (n_left_from > 3))
              {
                vlib_buffer_t * p1 = vlib_get_buffer(vm, from[3]);
                vnet_classify_table_t * tp1;
                u32 table_index1;
                u64 phash1;
  
                table_index1 = vnet_buffer(p1)->l2_classify.table_index;
                
                if (PREDICT_TRUE (table_index1 != ~0))
                  {
                    tp1 = pool_elt_at_index (vcm->tables, table_index1);
                    phash1 = vnet_buffer(p1)->l2_classify.hash;
                    vnet_classify_prefetch_entry (tp1, phash1); 
                  }
              }
  
            /* 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);
            h0 = b0->data;
            table_index0 = vnet_buffer(b0)->l2_classify.table_index;
            e0 = 0;
            t0 = 0;
            vnet_buffer(b0)->l2_classify.opaque_index = ~0;
  
            if (PREDICT_TRUE(table_index0 != ~0))
              {
                hash0 = vnet_buffer(b0)->l2_classify.hash;
                t0 = pool_elt_at_index (vcm->tables, table_index0);
  
                e0 = vnet_classify_find_entry (t0, (u8 *) h0, hash0,
                                               now);
                if (e0)
                  {
                    vnet_buffer(b0)->l2_classify.opaque_index
                      = e0->opaque_index;
                    vlib_buffer_advance (b0, e0->advance);
                    next0 = (e0->next_index < node->n_next_nodes)?
                             e0->next_index:next0;
                    hits++;
                  }
                else
                  {
                    while (1)
                      {
                        if (t0->next_table_index != ~0)
                          t0 = pool_elt_at_index (vcm->tables,
                                                  t0->next_table_index);
                        else
                          {
                            next0 = (t0->miss_next_index < n_next) ?
                                     t0->miss_next_index : next0;
                            misses++;
                            break;
                          }
  
                        hash0 = vnet_classify_hash_packet (t0, (u8 *) h0);
                        e0 = vnet_classify_find_entry
                          (t0, (u8 *) h0, hash0, now);
                        if (e0)
                          {
                            vnet_buffer(b0)->l2_classify.opaque_index
                              = e0->opaque_index;
                            vlib_buffer_advance (b0, e0->advance);
                            next0 = (e0->next_index < node->n_next_nodes)?
                                     e0->next_index:next0;
                            hits++;
                            chain_hits++;
                            break;
                          }
                      }
                  }
              }
  
            if (PREDICT_FALSE((node->flags & VLIB_NODE_FLAG_TRACE) 
                              && (b0->flags & VLIB_BUFFER_IS_TRACED))) 
              {
                ip_classify_trace_t *t = 
                  vlib_add_trace (vm, node, b0, sizeof (*t));
                t->next_index = next0;
                t->table_index = t0 ? t0 - vcm->tables : ~0;
                t->entry_index = e0 ? e0 - t0->entries : ~0;
              }
  
            /* 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, node->node_index, 
                                 IP_CLASSIFY_ERROR_MISS, 
                                 misses);
    vlib_node_increment_counter (vm, node->node_index, 
                                 IP_CLASSIFY_ERROR_HIT, 
                                 hits);
    vlib_node_increment_counter (vm, node->node_index, 
                                 IP_CLASSIFY_ERROR_CHAIN_HIT, 
                                 chain_hits);
    return frame->n_vectors;
  }
  
  static uword
  ip4_classify (vlib_main_t * vm,
                vlib_node_runtime_t * node,
                vlib_frame_t * frame)
  {
    return ip_classify_inline (vm, node, frame, 1 /* is_ip4 */);
  }
  
  
  VLIB_REGISTER_NODE (ip4_classify_node) = {
    .function = ip4_classify,
    .name = "ip4-classify",
    .vector_size = sizeof (u32),
    .sibling_of = "ip4-lookup",
    .format_trace = format_ip_classify_trace,
    .n_errors = ARRAY_LEN(ip_classify_error_strings),
    .error_strings = ip_classify_error_strings,
  
    .n_next_nodes = 0,
  };
  
  VLIB_NODE_FUNCTION_MULTIARCH (ip4_classify_node, ip4_classify)
  
  static uword
  ip6_classify (vlib_main_t * vm,
                vlib_node_runtime_t * node,
                vlib_frame_t * frame)
  {
    return ip_classify_inline (vm, node, frame, 0 /* is_ip4 */);
  }
  
  
  VLIB_REGISTER_NODE (ip6_classify_node) = {
    .function = ip6_classify,
    .name = "ip6-classify",
    .vector_size = sizeof (u32),
    .sibling_of = "ip6-lookup",
    .format_trace = format_ip_classify_trace,
    .n_errors = ARRAY_LEN(ip_classify_error_strings),
    .error_strings = ip_classify_error_strings,
  
    .n_next_nodes = 0,
  };
  
  VLIB_NODE_FUNCTION_MULTIARCH (ip6_classify_node, ip6_classify)
  
  static clib_error_t *
  ip_classify_init (vlib_main_t * vm)
  {
    return 0;
  }
  
  VLIB_INIT_FUNCTION (ip_classify_init);
  