2 * Copyright (c) 2015 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
16 * trace.c: VLIB trace buffer.
18 * Copyright (c) 2008 Eliot Dresselhaus
20 * Permission is hereby granted, free of charge, to any person obtaining
21 * a copy of this software and associated documentation files (the
22 * "Software"), to deal in the Software without restriction, including
23 * without limitation the rights to use, copy, modify, merge, publish,
24 * distribute, sublicense, and/or sell copies of the Software, and to
25 * permit persons to whom the Software is furnished to do so, subject to
26 * the following conditions:
28 * The above copyright notice and this permission notice shall be
29 * included in all copies or substantial portions of the Software.
31 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
32 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
33 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
34 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
35 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
36 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
37 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
40 #include <vlib/vlib.h>
41 #include <vlib/threads.h>
43 u8 *vnet_trace_placeholder;
45 /* Helper function for nodes which only trace buffer data. */
47 vlib_trace_frame_buffers_only (vlib_main_t * vm,
48 vlib_node_runtime_t * node,
51 uword next_buffer_stride,
52 uword n_buffer_data_bytes_in_trace)
62 vlib_buffer_t *b0, *b1;
65 /* Prefetch next iteration. */
66 vlib_prefetch_buffer_with_index (vm, from[2], LOAD);
67 vlib_prefetch_buffer_with_index (vm, from[3], LOAD);
72 b0 = vlib_get_buffer (vm, bi0);
73 b1 = vlib_get_buffer (vm, bi1);
75 if (b0->flags & VLIB_BUFFER_IS_TRACED)
77 t0 = vlib_add_trace (vm, node, b0, n_buffer_data_bytes_in_trace);
78 clib_memcpy_fast (t0, b0->data + b0->current_data,
79 n_buffer_data_bytes_in_trace);
81 if (b1->flags & VLIB_BUFFER_IS_TRACED)
83 t1 = vlib_add_trace (vm, node, b1, n_buffer_data_bytes_in_trace);
84 clib_memcpy_fast (t1, b1->data + b1->current_data,
85 n_buffer_data_bytes_in_trace);
99 b0 = vlib_get_buffer (vm, bi0);
101 if (b0->flags & VLIB_BUFFER_IS_TRACED)
103 t0 = vlib_add_trace (vm, node, b0, n_buffer_data_bytes_in_trace);
104 clib_memcpy_fast (t0, b0->data + b0->current_data,
105 n_buffer_data_bytes_in_trace);
112 /* Free up all trace buffer memory. */
114 clear_trace_buffer (void)
117 vlib_trace_main_t *tm;
122 tm = &this_vlib_main->trace_main;
124 tm->trace_enable = 0;
125 vec_free (tm->nodes);
130 tm = &this_vlib_main->trace_main;
132 for (i = 0; i < vec_len (tm->trace_buffer_pool); i++)
133 if (! pool_is_free_index (tm->trace_buffer_pool, i))
134 vec_free (tm->trace_buffer_pool[i]);
135 pool_free (tm->trace_buffer_pool);
141 format_vlib_trace (u8 * s, va_list * va)
143 vlib_main_t *vm = va_arg (*va, vlib_main_t *);
144 vlib_trace_header_t *h = va_arg (*va, vlib_trace_header_t *);
145 vlib_trace_header_t *e = vec_end (h);
146 vlib_node_t *node, *prev_node;
147 clib_time_t *ct = &vm->clib_time;
153 node = vlib_get_node (vm, h->node_index);
155 if (node != prev_node)
158 (h->time - vm->cpu_time_main_loop_start) * ct->seconds_per_clock;
160 format (s, "\n%U: %v", format_time_interval, "h:m:s:u", t,
165 if (node->format_trace)
166 s = format (s, "\n %U", node->format_trace, vm, node, h->data);
168 s = format (s, "\n %U", node->format_buffer, h->data);
170 h = vlib_trace_header_next (h);
176 /* Root of all trace cli commands. */
178 VLIB_CLI_COMMAND (trace_cli_command,static) = {
180 .short_help = "Packet tracer commands",
185 trace_time_cmp (void *a1, void *a2)
187 vlib_trace_header_t **t1 = a1;
188 vlib_trace_header_t **t2 = a2;
189 i64 dt = t1[0]->time - t2[0]->time;
190 return dt < 0 ? -1 : (dt > 0 ? +1 : 0);
194 * Return 1 if this packet passes the trace filter, or 0 otherwise
197 filter_accept (vlib_trace_main_t * tm, vlib_trace_header_t * h)
199 vlib_trace_header_t *e = vec_end (h);
201 if (tm->filter_flag == 0)
204 if (tm->filter_flag == FILTER_FLAG_INCLUDE)
208 if (h->node_index == tm->filter_node_index)
210 h = vlib_trace_header_next (h);
214 else /* FILTER_FLAG_EXCLUDE */
218 if (h->node_index == tm->filter_node_index)
220 h = vlib_trace_header_next (h);
229 * Remove traces from the trace buffer pool that don't pass the filter
232 trace_apply_filter (vlib_main_t * vm)
234 vlib_trace_main_t *tm = &vm->trace_main;
235 vlib_trace_header_t **h;
236 vlib_trace_header_t ***traces_to_remove = 0;
243 if (tm->filter_flag == FILTER_FLAG_NONE)
247 * Ideally we would retain the first N traces that pass the filter instead
252 pool_foreach (h, tm->trace_buffer_pool,
254 accept = filter_accept(tm, h[0]);
256 if ((n_accepted == tm->filter_count) || !accept)
257 vec_add1 (traces_to_remove, h);
263 /* remove all traces that we don't want to keep */
264 for (index = 0; index < vec_len (traces_to_remove); index++)
266 trace_index = traces_to_remove[index] - tm->trace_buffer_pool;
267 _vec_len (tm->trace_buffer_pool[trace_index]) = 0;
268 pool_put_index (tm->trace_buffer_pool, trace_index);
271 vec_free (traces_to_remove);
274 static clib_error_t *
275 cli_show_trace_buffer (vlib_main_t * vm,
276 unformat_input_t * input, vlib_cli_command_t * cmd)
278 vlib_trace_main_t *tm;
279 vlib_trace_header_t **h, **traces;
286 * By default display only this many traces. To display more, explicitly
287 * specify a max. This prevents unexpectedly huge outputs.
290 while (unformat_check_input (input) != (uword) UNFORMAT_END_OF_INPUT)
292 if (unformat (input, "max %d", &max))
295 return clib_error_create ("expected 'max COUNT', got `%U'",
296 format_unformat_error, input);
300 /* Get active traces from pool. */
305 fmt = "------------------- Start of thread %d %s -------------------\n";
306 s = format (s, fmt, index, vlib_worker_threads[index].name);
308 tm = &this_vlib_main->trace_main;
310 trace_apply_filter(this_vlib_main);
313 pool_foreach (h, tm->trace_buffer_pool,
315 vec_add1 (traces, h[0]);
318 if (vec_len (traces) == 0)
320 s = format (s, "No packets in trace buffer\n");
324 /* Sort them by increasing time. */
325 vec_sort_with_function (traces, trace_time_cmp);
327 for (i = 0; i < vec_len (traces); i++)
331 vlib_cli_output (vm, "Limiting display to %d packets."
332 " To display more specify max.", max);
336 s = format (s, "Packet %d\n%U\n\n", i + 1,
337 format_vlib_trace, vm, traces[i]);
347 vlib_cli_output (vm, "%v", s);
353 VLIB_CLI_COMMAND (show_trace_cli,static) = {
354 .path = "show trace",
355 .short_help = "Show trace buffer [max COUNT]",
356 .function = cli_show_trace_buffer,
360 int vlib_enable_disable_pkt_trace_filter (int enable) __attribute__ ((weak));
363 vlib_enable_disable_pkt_trace_filter (int enable)
369 vlib_trace_stop_and_clear (void)
371 vlib_enable_disable_pkt_trace_filter (0); /* disble tracing */
372 clear_trace_buffer ();
377 trace_update_capture_options (u32 add, u32 node_index, u32 filter, u8 verbose)
379 vlib_trace_main_t *tm;
380 vlib_trace_node_t *tn;
388 tm = &this_vlib_main->trace_main;
389 tm->verbose = verbose;
390 vec_validate (tm->nodes, node_index);
391 tn = tm->nodes + node_index;
394 * Adding 0 makes no real sense, and there wa no other way
395 * to explicilty zero-out the limits and count, so make
396 * an "add 0" request really be "set to 0".
399 tn->limit = tn->count = 0;
406 tm = &this_vlib_main->trace_main;
407 tm->trace_enable = 1;
412 static clib_error_t *
413 cli_add_trace_buffer (vlib_main_t * vm,
414 unformat_input_t * input, vlib_cli_command_t * cmd)
416 unformat_input_t _line_input, *line_input = &_line_input;
421 clib_error_t *error = 0;
423 if (!unformat_user (input, unformat_line_input, line_input))
426 if (vnet_trace_placeholder == 0)
427 vec_validate_aligned (vnet_trace_placeholder, 2048,
428 CLIB_CACHE_LINE_BYTES);
430 while (unformat_check_input (line_input) != (uword) UNFORMAT_END_OF_INPUT)
432 if (unformat (line_input, "%U %d",
433 unformat_vlib_node, vm, &node_index, &add))
435 else if (unformat (line_input, "verbose"))
437 else if (unformat (line_input, "filter"))
441 error = clib_error_create ("expected NODE COUNT, got `%U'",
442 format_unformat_error, line_input);
447 node = vlib_get_node (vm, node_index);
449 if ((node->flags & VLIB_NODE_FLAG_TRACE_SUPPORTED) == 0)
451 error = clib_error_create ("node '%U' doesn't support per-node "
452 "tracing. There may be another way to "
453 "initiate trace on this node.",
454 format_vlib_node_name, vm, node_index);
460 if (vlib_enable_disable_pkt_trace_filter (1 /* enable */ ))
462 error = clib_error_create ("No packet trace filter configured...");
467 trace_update_capture_options (add, node_index, filter, verbose);
470 unformat_free (line_input);
476 VLIB_CLI_COMMAND (add_trace_cli,static) = {
478 .short_help = "trace add <input-graph-node> <add'l-pkts-for-node-> [filter] [verbose]",
479 .function = cli_add_trace_buffer,
484 * Configure a filter for packet traces.
486 * This supplements the packet trace feature so that only packets matching
487 * the filter are included in the trace. Currently the only filter is to
488 * keep packets that include a certain node in the trace or exclude a certain
491 * The count of traced packets in the "trace add" command is still used to
492 * create a certain number of traces. The "trace filter" command specifies
493 * how many of those packets should be retained in the trace.
495 * For example, 1Mpps of traffic is arriving and one of those packets is being
496 * dropped. To capture the trace for only that dropped packet, you can do:
497 * trace filter include error-drop 1
498 * trace add dpdk-input 1000000
502 * Note that the filter could be implemented by capturing all traces and just
503 * reducing traces displayed by the "show trace" function. But that would
504 * require a lot of memory for storing the traces, making that infeasible.
506 * To remove traces from the trace pool that do not include a certain node
507 * requires that the trace be "complete" before applying the filter. To
508 * accomplish this, the trace pool is filtered upon each iteraction of the
509 * main vlib loop. Doing so keeps the number of allocated traces down to a
510 * reasonably low number. This requires that tracing for a buffer is not
511 * performed after the vlib main loop interation completes. i.e. you can't
512 * save away a buffer temporarily then inject it back into the graph and
513 * expect that the trace_index is still valid (such as a traffic manager might
514 * do). A new trace buffer should be allocated for those types of packets.
516 * The filter can be extended to support multiple nodes and other match
517 * criteria (e.g. input sw_if_index, mac address) but for now just checks if
518 * a specified node is in the trace or not in the trace.
522 trace_filter_set (u32 node_index, u32 flag, u32 count)
527 vlib_trace_main_t *tm;
529 tm = &this_vlib_main->trace_main;
530 tm->filter_node_index = node_index;
531 tm->filter_flag = flag;
532 tm->filter_count = count;
535 * Clear the trace limits to stop any in-progress tracing
536 * Prevents runaway trace allocations when the filter changes
539 vec_free (tm->nodes);
545 static clib_error_t *
546 cli_filter_trace (vlib_main_t * vm,
547 unformat_input_t * input, vlib_cli_command_t * cmd)
549 u32 filter_node_index;
553 if (unformat (input, "include %U %d",
554 unformat_vlib_node, vm, &filter_node_index, &filter_count))
556 filter_flag = FILTER_FLAG_INCLUDE;
558 else if (unformat (input, "exclude %U %d",
559 unformat_vlib_node, vm, &filter_node_index,
562 filter_flag = FILTER_FLAG_EXCLUDE;
564 else if (unformat (input, "none"))
566 filter_flag = FILTER_FLAG_NONE;
567 filter_node_index = 0;
573 ("expected 'include NODE COUNT' or 'exclude NODE COUNT' or 'none', got `%U'",
574 format_unformat_error, input);
576 trace_filter_set (filter_node_index, filter_flag, filter_count);
582 VLIB_CLI_COMMAND (filter_trace_cli,static) = {
583 .path = "trace filter",
584 .short_help = "trace filter none | [include|exclude] NODE COUNT",
585 .function = cli_filter_trace,
589 static clib_error_t *
590 cli_clear_trace_buffer (vlib_main_t * vm,
591 unformat_input_t * input, vlib_cli_command_t * cmd)
593 vlib_trace_stop_and_clear ();
598 VLIB_CLI_COMMAND (clear_trace_cli,static) = {
599 .path = "clear trace",
600 .short_help = "Clear trace buffer and free memory",
601 .function = cli_clear_trace_buffer,
605 /* Placeholder function to get us linked in. */
607 vlib_trace_cli_reference (void)
612 vnet_is_packet_traced (vlib_buffer_t * b,
613 u32 classify_table_index, int func)
614 __attribute__ ((weak));
617 vnet_is_packet_traced (vlib_buffer_t * b, u32 classify_table_index, int func)
619 clib_warning ("BUG: STUB called");
624 vlib_add_trace (vlib_main_t * vm,
625 vlib_node_runtime_t * r, vlib_buffer_t * b, u32 n_data_bytes)
627 return vlib_add_trace_inline (vm, r, b, n_data_bytes);
633 * fd.io coding-style-patch-verification: ON
636 * eval: (c-set-style "gnu")