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.
   */
  /*
   * trace_funcs.h: VLIB trace buffer.
   *
   * Copyright (c) 2008 Eliot Dresselhaus
   *
   * Permission is hereby granted, free of charge, to any person obtaining
   * a copy of this software and associated documentation files (the
   * "Software"), to deal in the Software without restriction, including
   * without limitation the rights to use, copy, modify, merge, publish,
   * distribute, sublicense, and/or sell copies of the Software, and to
   * permit persons to whom the Software is furnished to do so, subject to
   * the following conditions:
   *
   * The above copyright notice and this permission notice shall be
   * included in all copies or substantial portions of the Software.
   *
   *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
   *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
   *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
   *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
   *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
   *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
   */
  
  #ifndef included_vlib_trace_funcs_h
  #define included_vlib_trace_funcs_h
  
  extern u8 *vnet_trace_placeholder;
  
  always_inline void
  vlib_validate_trace (vlib_trace_main_t * tm, vlib_buffer_t * b)
  {
    ASSERT (!pool_is_free_index (tm->trace_buffer_pool,
  			       vlib_buffer_get_trace_index (b)));
  }
  
  int vlib_add_handoff_trace (vlib_main_t * vm, vlib_buffer_t * b);
  
  always_inline void *
  vlib_add_trace_inline (vlib_main_t * vm,
  		       vlib_node_runtime_t * r, vlib_buffer_t * b,
  		       u32 n_data_bytes)
  {
    vlib_trace_main_t *tm = &vm->trace_main;
    vlib_trace_header_t *h;
    u32 n_data_words;
  
    ASSERT (vnet_trace_placeholder);
  
    if (PREDICT_FALSE ((b->flags & VLIB_BUFFER_IS_TRACED) == 0))
      return vnet_trace_placeholder;
  
    if (PREDICT_FALSE (tm->add_trace_callback != 0))
      {
        return tm->add_trace_callback ((struct vlib_main_t *) vm,
  				     (struct vlib_node_runtime_t *) r,
  				     (struct vlib_buffer_t *) b,
  				     n_data_bytes);
      }
    else if (PREDICT_FALSE (tm->trace_enable == 0))
      {
        ASSERT (vec_len (vnet_trace_placeholder) >= n_data_bytes + sizeof (*h));
        return vnet_trace_placeholder;
      }
  
    /* Are we trying to trace a handoff case? */
    if (PREDICT_FALSE (vlib_buffer_get_trace_thread (b) != vm->thread_index))
      if (PREDICT_FALSE (!vlib_add_handoff_trace (vm, b)))
        return vnet_trace_placeholder;
  
    vlib_validate_trace (tm, b);
  
    n_data_bytes = round_pow2 (n_data_bytes, sizeof (h[0]));
    n_data_words = n_data_bytes / sizeof (h[0]);
    vec_add2_aligned (tm->trace_buffer_pool[vlib_buffer_get_trace_index (b)], h,
  		    1 + n_data_words, sizeof (h[0]));
  
    h->time = vm->cpu_time_last_node_dispatch;
    h->n_data = n_data_words;
    h->node_index = r->node_index;
  
    return h->data;
  }
  
  /* Non-inline (typical use-case) version of the above */
  void *vlib_add_trace (vlib_main_t * vm,
  		      vlib_node_runtime_t * r, vlib_buffer_t * b,
  		      u32 n_data_bytes);
  
  always_inline vlib_trace_header_t *
  vlib_trace_header_next (vlib_trace_header_t * h)
  {
    return h + 1 + h->n_data;
  }
  
  always_inline void
  vlib_free_trace (vlib_main_t * vm, vlib_buffer_t * b)
  {
    vlib_trace_main_t *tm = &vm->trace_main;
    u32 trace_index = vlib_buffer_get_trace_index (b);
    vlib_validate_trace (tm, b);
    _vec_len (tm->trace_buffer_pool[trace_index]) = 0;
    pool_put_index (tm->trace_buffer_pool, trace_index);
  }
  
  always_inline void
  vlib_trace_next_frame (vlib_main_t * vm,
  		       vlib_node_runtime_t * r, u32 next_index)
  {
    vlib_next_frame_t *nf;
    nf = vlib_node_runtime_get_next_frame (vm, r, next_index);
    nf->flags |= VLIB_FRAME_TRACE;
  }
  
  void trace_apply_filter (vlib_main_t * vm);
  int vnet_is_packet_traced (vlib_buffer_t * b,
  			   u32 classify_table_index, int func);
  
  
  /*
   * Mark buffer as traced and allocate trace buffer.
   * return 1 if the buffer is successfully traced, 0 if not
   * A buffer might not be traced if tracing is off or if the packet did not
   * match the filter.
   */
  always_inline __clib_warn_unused_result int
  vlib_trace_buffer (vlib_main_t * vm,
  		   vlib_node_runtime_t * r,
  		   u32 next_index, vlib_buffer_t * b, int follow_chain)
  {
    vlib_trace_main_t *tm = &vm->trace_main;
    vlib_trace_header_t **h;
  
    if (PREDICT_FALSE (tm->trace_enable == 0))
      return 0;
  
    /* Classifier filter in use? */
    if (PREDICT_FALSE (vlib_global_main.trace_filter.trace_filter_enable))
      {
        /* See if we're supposed to trace this packet... */
        if (vnet_is_packet_traced
  	  (b, vlib_global_main.trace_filter.classify_table_index,
  	   0 /* full classify */ ) != 1)
  	return 0;
      }
  
    /*
     * Apply filter to existing traces to keep number of allocated traces low.
     * Performed each time around the main loop.
     */
    if (tm->last_main_loop_count != vm->main_loop_count)
      {
        tm->last_main_loop_count = vm->main_loop_count;
        trace_apply_filter (vm);
  
        if (tm->trace_buffer_callback)
  	(tm->trace_buffer_callback) ((struct vlib_main_t *) vm,
  				     (struct vlib_trace_main_t *) tm);
      }
  
    vlib_trace_next_frame (vm, r, next_index);
  
    pool_get (tm->trace_buffer_pool, h);
  
    do
      {
        b->flags |= VLIB_BUFFER_IS_TRACED;
        b->trace_handle = vlib_buffer_make_trace_handle
  	(vm->thread_index, h - tm->trace_buffer_pool);
      }
    while (follow_chain && (b = vlib_get_next_buffer (vm, b)));
  
    return 1;
  }
  
  always_inline void
  vlib_buffer_copy_trace_flag (vlib_main_t * vm, vlib_buffer_t * b,
  			     u32 bi_target)
  {
    vlib_buffer_t *b_target = vlib_get_buffer (vm, bi_target);
    b_target->flags |= b->flags & VLIB_BUFFER_IS_TRACED;
    b_target->trace_handle = b->trace_handle;
  }
  
  always_inline u32
  vlib_get_trace_count (vlib_main_t * vm, vlib_node_runtime_t * rt)
  {
    vlib_trace_main_t *tm = &vm->trace_main;
    vlib_trace_node_t *tn;
  
    if (rt->node_index >= vec_len (tm->nodes))
      return 0;
    tn = tm->nodes + rt->node_index;
    ASSERT (tn->count <= tn->limit);
  
    return tn->limit - tn->count;
  }
  
  always_inline void
  vlib_set_trace_count (vlib_main_t * vm, vlib_node_runtime_t * rt, u32 count)
  {
    vlib_trace_main_t *tm = &vm->trace_main;
    vlib_trace_node_t *tn = vec_elt_at_index (tm->nodes, rt->node_index);
  
    ASSERT (count <= tn->limit);
    tn->count = tn->limit - count;
  }
  
  /* Helper function for nodes which only trace buffer data. */
  void
  vlib_trace_frame_buffers_only (vlib_main_t * vm,
  			       vlib_node_runtime_t * node,
  			       u32 * buffers,
  			       uword n_buffers,
  			       uword next_buffer_stride,
  			       uword n_buffer_data_bytes_in_trace);
  
  #endif /* included_vlib_trace_funcs_h */
  
  /*
   * fd.io coding-style-patch-verification: ON
   *
   * Local Variables:
   * eval: (c-set-style "gnu")
   * End:
   */
  