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Diffstat (limited to 'src/vlib/trace.c')
-rw-r--r-- | src/vlib/trace.c | 545 |
1 files changed, 545 insertions, 0 deletions
diff --git a/src/vlib/trace.c b/src/vlib/trace.c new file mode 100644 index 00000000000..dcdb837f16c --- /dev/null +++ b/src/vlib/trace.c @@ -0,0 +1,545 @@ +/* + * 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.c: 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. + */ + +#include <vlib/vlib.h> +#include <vlib/threads.h> + +/* 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) +{ + u32 n_left, *from; + + n_left = n_buffers; + from = buffers; + + while (n_left >= 4) + { + u32 bi0, bi1; + vlib_buffer_t *b0, *b1; + u8 *t0, *t1; + + /* Prefetch next iteration. */ + vlib_prefetch_buffer_with_index (vm, from[2], LOAD); + vlib_prefetch_buffer_with_index (vm, from[3], LOAD); + + bi0 = from[0]; + bi1 = from[1]; + + b0 = vlib_get_buffer (vm, bi0); + b1 = vlib_get_buffer (vm, bi1); + + if (b0->flags & VLIB_BUFFER_IS_TRACED) + { + t0 = vlib_add_trace (vm, node, b0, n_buffer_data_bytes_in_trace); + clib_memcpy (t0, b0->data + b0->current_data, + n_buffer_data_bytes_in_trace); + } + if (b1->flags & VLIB_BUFFER_IS_TRACED) + { + t1 = vlib_add_trace (vm, node, b1, n_buffer_data_bytes_in_trace); + clib_memcpy (t1, b1->data + b1->current_data, + n_buffer_data_bytes_in_trace); + } + from += 2; + n_left -= 2; + } + + while (n_left >= 1) + { + u32 bi0; + vlib_buffer_t *b0; + u8 *t0; + + bi0 = from[0]; + + b0 = vlib_get_buffer (vm, bi0); + + if (b0->flags & VLIB_BUFFER_IS_TRACED) + { + t0 = vlib_add_trace (vm, node, b0, n_buffer_data_bytes_in_trace); + clib_memcpy (t0, b0->data + b0->current_data, + n_buffer_data_bytes_in_trace); + } + from += 1; + n_left -= 1; + } +} + +/* Free up all trace buffer memory. */ +always_inline void +clear_trace_buffer (void) +{ + int i; + vlib_trace_main_t *tm; + + /* *INDENT-OFF* */ + foreach_vlib_main ( + ({ + void *mainheap; + + tm = &this_vlib_main->trace_main; + mainheap = clib_mem_set_heap (this_vlib_main->heap_base); + + tm->trace_active_hint = 0; + + for (i = 0; i < vec_len (tm->trace_buffer_pool); i++) + if (! pool_is_free_index (tm->trace_buffer_pool, i)) + vec_free (tm->trace_buffer_pool[i]); + pool_free (tm->trace_buffer_pool); + clib_mem_set_heap (mainheap); + })); + /* *INDENT-ON* */ +} + +static u8 * +format_vlib_trace (u8 * s, va_list * va) +{ + vlib_main_t *vm = va_arg (*va, vlib_main_t *); + vlib_trace_header_t *h = va_arg (*va, vlib_trace_header_t *); + vlib_trace_header_t *e = vec_end (h); + vlib_node_t *node, *prev_node; + clib_time_t *ct = &vm->clib_time; + f64 t; + + prev_node = 0; + while (h < e) + { + node = vlib_get_node (vm, h->node_index); + + if (node != prev_node) + { + t = + (h->time - vm->cpu_time_main_loop_start) * ct->seconds_per_clock; + s = + format (s, "\n%U: %v", format_time_interval, "h:m:s:u", t, + node->name); + } + prev_node = node; + + if (node->format_trace) + s = format (s, "\n %U", node->format_trace, vm, node, h->data); + else + s = format (s, "\n %U", node->format_buffer, h->data); + + h = vlib_trace_header_next (h); + } + + return s; +} + +/* Root of all trace cli commands. */ +/* *INDENT-OFF* */ +VLIB_CLI_COMMAND (trace_cli_command,static) = { + .path = "trace", + .short_help = "Packet tracer commands", +}; +/* *INDENT-ON* */ + +static int +trace_cmp (void *a1, void *a2) +{ + vlib_trace_header_t **t1 = a1; + vlib_trace_header_t **t2 = a2; + i64 dt = t1[0]->time - t2[0]->time; + return dt < 0 ? -1 : (dt > 0 ? +1 : 0); +} + +/* + * Return 1 if this packet passes the trace filter, or 0 otherwise + */ +u32 +filter_accept (vlib_trace_main_t * tm, vlib_trace_header_t * h) +{ + vlib_trace_header_t *e = vec_end (h); + + if (tm->filter_flag == 0) + return 1; + + if (tm->filter_flag == FILTER_FLAG_INCLUDE) + { + while (h < e) + { + if (h->node_index == tm->filter_node_index) + return 1; + h = vlib_trace_header_next (h); + } + return 0; + } + else /* FILTER_FLAG_EXCLUDE */ + { + while (h < e) + { + if (h->node_index == tm->filter_node_index) + return 0; + h = vlib_trace_header_next (h); + } + return 1; + } + + return 0; +} + +/* + * Remove traces from the trace buffer pool that don't pass the filter + */ +void +trace_apply_filter (vlib_main_t * vm) +{ + vlib_trace_main_t *tm = &vm->trace_main; + vlib_trace_header_t **h; + vlib_trace_header_t ***traces_to_remove = 0; + u32 index; + u32 trace_index; + u32 n_accepted; + + u32 accept; + + if (tm->filter_flag == FILTER_FLAG_NONE) + return; + + /* + * Ideally we would retain the first N traces that pass the filter instead + * of any N traces. + */ + n_accepted = 0; + /* *INDENT-OFF* */ + pool_foreach (h, tm->trace_buffer_pool, + ({ + accept = filter_accept(tm, h[0]); + + if ((n_accepted == tm->filter_count) || !accept) + vec_add1 (traces_to_remove, h); + else + n_accepted++; + })); + /* *INDENT-ON* */ + + /* remove all traces that we don't want to keep */ + for (index = 0; index < vec_len (traces_to_remove); index++) + { + trace_index = traces_to_remove[index] - tm->trace_buffer_pool; + _vec_len (tm->trace_buffer_pool[trace_index]) = 0; + pool_put_index (tm->trace_buffer_pool, trace_index); + } + + vec_free (traces_to_remove); +} + +static clib_error_t * +cli_show_trace_buffer (vlib_main_t * vm, + unformat_input_t * input, vlib_cli_command_t * cmd) +{ + vlib_trace_main_t *tm; + vlib_trace_header_t **h, **traces; + u32 i, index = 0; + char *fmt; + u8 *s = 0; + u32 max; + + /* + * By default display only this many traces. To display more, explicitly + * specify a max. This prevents unexpectedly huge outputs. + */ + max = 50; + while (unformat_check_input (input) != (uword) UNFORMAT_END_OF_INPUT) + { + if (unformat (input, "max %d", &max)) + ; + else + return clib_error_create ("expected 'max COUNT', got `%U'", + format_unformat_error, input); + } + + + /* Get active traces from pool. */ + + /* *INDENT-OFF* */ + foreach_vlib_main ( + ({ + void *mainheap; + + fmt = "------------------- Start of thread %d %s -------------------\n"; + s = format (s, fmt, index, vlib_worker_threads[index].name); + + tm = &this_vlib_main->trace_main; + + mainheap = clib_mem_set_heap (this_vlib_main->heap_base); + + trace_apply_filter(this_vlib_main); + + traces = 0; + pool_foreach (h, tm->trace_buffer_pool, + ({ + vec_add1 (traces, h[0]); + })); + + if (vec_len (traces) == 0) + { + clib_mem_set_heap (mainheap); + s = format (s, "No packets in trace buffer\n"); + goto done; + } + + /* Sort them by increasing time. */ + vec_sort_with_function (traces, trace_cmp); + + for (i = 0; i < vec_len (traces); i++) + { + if (i == max) + { + vlib_cli_output (vm, "Limiting display to %d packets." + " To display more specify max.", max); + goto done; + } + + clib_mem_set_heap (mainheap); + + s = format (s, "Packet %d\n%U\n\n", i + 1, + format_vlib_trace, vm, traces[i]); + + mainheap = clib_mem_set_heap (this_vlib_main->heap_base); + } + + done: + vec_free (traces); + clib_mem_set_heap (mainheap); + + index++; + })); + /* *INDENT-ON* */ + + vlib_cli_output (vm, "%v", s); + vec_free (s); + return 0; +} + +/* *INDENT-OFF* */ +VLIB_CLI_COMMAND (show_trace_cli,static) = { + .path = "show trace", + .short_help = "Show trace buffer [max COUNT]", + .function = cli_show_trace_buffer, +}; +/* *INDENT-ON* */ + +static clib_error_t * +cli_add_trace_buffer (vlib_main_t * vm, + unformat_input_t * input, vlib_cli_command_t * cmd) +{ + unformat_input_t _line_input, *line_input = &_line_input; + vlib_trace_main_t *tm; + vlib_trace_node_t *tn; + u32 node_index, add; + u8 verbose = 0; + + if (!unformat_user (input, unformat_line_input, line_input)) + return 0; + + while (unformat_check_input (line_input) != (uword) UNFORMAT_END_OF_INPUT) + { + if (unformat (line_input, "%U %d", + unformat_vlib_node, vm, &node_index, &add)) + ; + else if (unformat (line_input, "verbose")) + verbose = 1; + else + return clib_error_create ("expected NODE COUNT, got `%U'", + format_unformat_error, line_input); + } + + /* *INDENT-OFF* */ + foreach_vlib_main (( + { + void *oldheap; + tm = &this_vlib_main->trace_main; + tm->trace_active_hint = 1; + tm->verbose = verbose; + oldheap = + clib_mem_set_heap (this_vlib_main->heap_base); + vec_validate (tm->nodes, node_index); + tn = tm->nodes + node_index; + tn->limit += add; clib_mem_set_heap (oldheap); + })); + /* *INDENT-ON* */ + + return 0; +} + +/* *INDENT-OFF* */ +VLIB_CLI_COMMAND (add_trace_cli,static) = { + .path = "trace add", + .short_help = "Trace given number of packets", + .function = cli_add_trace_buffer, +}; +/* *INDENT-ON* */ + + +/* + * Configure a filter for packet traces. + * + * This supplements the packet trace feature so that only packets matching + * the filter are included in the trace. Currently the only filter is to + * keep packets that include a certain node in the trace or exclude a certain + * node in the trace. + * + * The count of traced packets in the "trace add" command is still used to + * create a certain number of traces. The "trace filter" command specifies + * how many of those packets should be retained in the trace. + * + * For example, 1Mpps of traffic is arriving and one of those packets is being + * dropped. To capture the trace for only that dropped packet, you can do: + * trace filter include error-drop 1 + * trace add dpdk-input 1000000 + * <wait one second> + * show trace + * + * Note that the filter could be implemented by capturing all traces and just + * reducing traces displayed by the "show trace" function. But that would + * require a lot of memory for storing the traces, making that infeasible. + * + * To remove traces from the trace pool that do not include a certain node + * requires that the trace be "complete" before applying the filter. To + * accomplish this, the trace pool is filtered upon each iteraction of the + * main vlib loop. Doing so keeps the number of allocated traces down to a + * reasonably low number. This requires that tracing for a buffer is not + * performed after the vlib main loop interation completes. i.e. you can't + * save away a buffer temporarily then inject it back into the graph and + * expect that the trace_index is still valid (such as a traffic manager might + * do). A new trace buffer should be allocated for those types of packets. + * + * The filter can be extended to support multiple nodes and other match + * criteria (e.g. input sw_if_index, mac address) but for now just checks if + * a specified node is in the trace or not in the trace. + */ +static clib_error_t * +cli_filter_trace (vlib_main_t * vm, + unformat_input_t * input, vlib_cli_command_t * cmd) +{ + vlib_trace_main_t *tm = &vm->trace_main; + u32 filter_node_index; + u32 filter_flag; + u32 filter_count; + void *mainheap; + + if (unformat (input, "include %U %d", + unformat_vlib_node, vm, &filter_node_index, &filter_count)) + { + filter_flag = FILTER_FLAG_INCLUDE; + } + else if (unformat (input, "exclude %U %d", + unformat_vlib_node, vm, &filter_node_index, + &filter_count)) + { + filter_flag = FILTER_FLAG_EXCLUDE; + } + else if (unformat (input, "none")) + { + filter_flag = FILTER_FLAG_NONE; + filter_node_index = 0; + filter_count = 0; + } + else + return + clib_error_create + ("expected 'include NODE COUNT' or 'exclude NODE COUNT' or 'none', got `%U'", + format_unformat_error, input); + + /* *INDENT-OFF* */ + foreach_vlib_main ( + ({ + tm = &this_vlib_main->trace_main; + tm->filter_node_index = filter_node_index; + tm->filter_flag = filter_flag; + tm->filter_count = filter_count; + + /* + * Clear the trace limits to stop any in-progress tracing + * Prevents runaway trace allocations when the filter changes (or is removed) + */ + mainheap = clib_mem_set_heap (this_vlib_main->heap_base); + vec_free (tm->nodes); + clib_mem_set_heap (mainheap); + })); + /* *INDENT-ON* */ + + return 0; +} + +/* *INDENT-OFF* */ +VLIB_CLI_COMMAND (filter_trace_cli,static) = { + .path = "trace filter", + .short_help = "filter trace output - include NODE COUNT | exclude NODE COUNT | none", + .function = cli_filter_trace, +}; +/* *INDENT-ON* */ + +static clib_error_t * +cli_clear_trace_buffer (vlib_main_t * vm, + unformat_input_t * input, vlib_cli_command_t * cmd) +{ + clear_trace_buffer (); + return 0; +} + +/* *INDENT-OFF* */ +VLIB_CLI_COMMAND (clear_trace_cli,static) = { + .path = "clear trace", + .short_help = "Clear trace buffer and free memory", + .function = cli_clear_trace_buffer, +}; +/* *INDENT-ON* */ + +/* Dummy function to get us linked in. */ +void +vlib_trace_cli_reference (void) +{ +} + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |