xref: /spdk/lib/trace_parser/trace.cpp (revision 588dfe314bb83d86effdf67ec42837b11c2620bf)
1 /*   SPDX-License-Identifier: BSD-3-Clause
2  *   Copyright (C) 2021 Intel Corporation.
3  *   All rights reserved.
4  */
5 
6 #include "spdk/stdinc.h"
7 #include "spdk/likely.h"
8 #include "spdk/log.h"
9 #include "spdk/trace_parser.h"
10 #include "spdk/util.h"
11 
12 #include <exception>
13 #include <map>
14 #include <new>
15 
16 struct entry_key {
17 	entry_key(uint16_t _lcore, uint64_t _tsc) : lcore(_lcore), tsc(_tsc) {}
18 	uint16_t lcore;
19 	uint64_t tsc;
20 };
21 
22 class compare_entry_key
23 {
24 public:
25 	bool operator()(const entry_key &first, const entry_key &second) const
26 	{
27 		if (first.tsc == second.tsc) {
28 			return first.lcore < second.lcore;
29 		} else {
30 			return first.tsc < second.tsc;
31 		}
32 	}
33 };
34 
35 typedef std::map<entry_key, spdk_trace_entry *, compare_entry_key> entry_map;
36 
37 struct argument_context {
38 	spdk_trace_entry	*entry;
39 	spdk_trace_entry_buffer	*buffer;
40 	uint16_t		lcore;
41 	size_t			offset;
42 
43 	argument_context(spdk_trace_entry *entry, uint16_t lcore) :
44 		entry(entry), lcore(lcore)
45 	{
46 		buffer = reinterpret_cast<spdk_trace_entry_buffer *>(entry);
47 
48 		/* The first argument resides within the spdk_trace_entry structure, so the initial
49 		 * offset needs to be adjusted to the start of the spdk_trace_entry.args array
50 		 */
51 		offset = offsetof(spdk_trace_entry, args) -
52 			 offsetof(spdk_trace_entry_buffer, data);
53 	}
54 };
55 
56 struct object_stats {
57 	std::map<uint64_t, uint64_t>	index;
58 	std::map<uint64_t, uint64_t>	start;
59 	uint64_t			counter;
60 
61 	object_stats() : counter(0) {}
62 };
63 
64 struct spdk_trace_parser {
65 	spdk_trace_parser(const spdk_trace_parser_opts *opts);
66 	~spdk_trace_parser();
67 	spdk_trace_parser(const spdk_trace_parser &) = delete;
68 	spdk_trace_parser &operator=(const spdk_trace_parser &) = delete;
69 	const spdk_trace_flags *flags() const { return &_histories->flags; }
70 	uint64_t tsc_offset() const { return _tsc_offset; }
71 	bool next_entry(spdk_trace_parser_entry *entry);
72 	uint64_t entry_count(uint16_t lcore) const;
73 private:
74 	spdk_trace_entry_buffer *get_next_buffer(spdk_trace_entry_buffer *buf, uint16_t lcore);
75 	bool build_arg(argument_context *argctx, const spdk_trace_argument *arg, int argid,
76 		       spdk_trace_parser_entry *pe);
77 	void populate_events(spdk_trace_history *history, int num_entries);
78 	bool init(const spdk_trace_parser_opts *opts);
79 	void cleanup();
80 
81 	spdk_trace_histories	*_histories;
82 	size_t			_map_size;
83 	int			_fd;
84 	uint64_t		_tsc_offset;
85 	entry_map		_entries;
86 	entry_map::iterator	_iter;
87 	object_stats		_stats[SPDK_TRACE_MAX_OBJECT];
88 };
89 
90 uint64_t
91 spdk_trace_parser::entry_count(uint16_t lcore) const
92 {
93 	spdk_trace_history *history;
94 
95 	if (lcore >= SPDK_TRACE_MAX_LCORE) {
96 		return 0;
97 	}
98 
99 	history = spdk_get_per_lcore_history(_histories, lcore);
100 
101 	return history == NULL ? 0 : history->num_entries;
102 }
103 
104 spdk_trace_entry_buffer *
105 spdk_trace_parser::get_next_buffer(spdk_trace_entry_buffer *buf, uint16_t lcore)
106 {
107 	spdk_trace_history *history;
108 
109 	history = spdk_get_per_lcore_history(_histories, lcore);
110 	assert(history);
111 
112 	if (spdk_unlikely(static_cast<void *>(buf) ==
113 			  static_cast<void *>(&history->entries[history->num_entries - 1]))) {
114 		return reinterpret_cast<spdk_trace_entry_buffer *>(&history->entries[0]);
115 	} else {
116 		return buf + 1;
117 	}
118 }
119 
120 bool
121 spdk_trace_parser::build_arg(argument_context *argctx, const spdk_trace_argument *arg, int argid,
122 			     spdk_trace_parser_entry *pe)
123 {
124 	spdk_trace_entry *entry = argctx->entry;
125 	spdk_trace_entry_buffer *buffer = argctx->buffer;
126 	size_t curlen, argoff;
127 
128 	argoff = 0;
129 	/* Make sure that if we only copy a 4-byte integer, that the upper bytes have already been
130 	 * zeroed.
131 	 */
132 	pe->args[argid].integer = 0;
133 	while (argoff < arg->size) {
134 		if (argctx->offset == sizeof(buffer->data)) {
135 			buffer = get_next_buffer(buffer, argctx->lcore);
136 			if (spdk_unlikely(buffer->tpoint_id != SPDK_TRACE_MAX_TPOINT_ID ||
137 					  buffer->tsc != entry->tsc)) {
138 				return false;
139 			}
140 
141 			argctx->offset = 0;
142 			argctx->buffer = buffer;
143 		}
144 
145 		curlen = spdk_min(sizeof(buffer->data) - argctx->offset, arg->size - argoff);
146 		if (argoff < sizeof(pe->args[0])) {
147 			memcpy(&pe->args[argid].string[argoff], &buffer->data[argctx->offset],
148 			       spdk_min(curlen, sizeof(pe->args[0]) - argoff));
149 		}
150 
151 		argctx->offset += curlen;
152 		argoff += curlen;
153 	}
154 
155 	return true;
156 }
157 
158 bool
159 spdk_trace_parser::next_entry(spdk_trace_parser_entry *pe)
160 {
161 	spdk_trace_tpoint *tpoint;
162 	spdk_trace_entry *entry;
163 	object_stats *stats;
164 	std::map<uint64_t, uint64_t>::iterator related_kv;
165 
166 	if (_iter == _entries.end()) {
167 		return false;
168 	}
169 
170 	pe->entry = entry = _iter->second;
171 	pe->lcore = _iter->first.lcore;
172 	/* Set related index to the max value to indicate "empty" state */
173 	pe->related_index = UINT64_MAX;
174 	pe->related_type = OBJECT_NONE;
175 	tpoint = &_histories->flags.tpoint[entry->tpoint_id];
176 	stats = &_stats[tpoint->object_type];
177 
178 	if (tpoint->new_object) {
179 		stats->index[entry->object_id] = stats->counter++;
180 		stats->start[entry->object_id] = entry->tsc;
181 	}
182 
183 	if (tpoint->object_type != OBJECT_NONE) {
184 		if (spdk_likely(stats->start.find(entry->object_id) != stats->start.end())) {
185 			pe->object_index = stats->index[entry->object_id];
186 			pe->object_start = stats->start[entry->object_id];
187 		} else {
188 			pe->object_index = UINT64_MAX;
189 			pe->object_start = UINT64_MAX;
190 		}
191 	}
192 
193 	argument_context argctx(entry, pe->lcore);
194 	for (uint8_t i = 0; i < tpoint->num_args; ++i) {
195 		if (!build_arg(&argctx, &tpoint->args[i], i, pe)) {
196 			SPDK_ERRLOG("Failed to parse tracepoint argument\n");
197 			return false;
198 		}
199 	}
200 
201 	for (uint8_t i = 0; i < SPDK_TRACE_MAX_RELATIONS; ++i) {
202 		/* The relations are stored inside a tpoint, which means there might be
203 		 * multiple objects bound to a single tpoint. */
204 		if (tpoint->related_objects[i].object_type == OBJECT_NONE) {
205 			break;
206 		}
207 		stats = &_stats[tpoint->related_objects[i].object_type];
208 		related_kv = stats->index.find(reinterpret_cast<uint64_t>
209 					       (pe->args[tpoint->related_objects[i].arg_index].pointer));
210 		/* To avoid parsing the whole array, object index and type are stored
211 		 * directly inside spdk_trace_parser_entry. */
212 		if (related_kv != stats->index.end()) {
213 			pe->related_index = related_kv->second;
214 			pe->related_type = tpoint->related_objects[i].object_type;
215 			break;
216 		}
217 	}
218 
219 	_iter++;
220 	return true;
221 }
222 
223 void
224 spdk_trace_parser::populate_events(spdk_trace_history *history, int num_entries)
225 {
226 	int i, num_entries_filled;
227 	spdk_trace_entry *e;
228 	int first, last, lcore;
229 
230 	lcore = history->lcore;
231 	e = history->entries;
232 
233 	num_entries_filled = num_entries;
234 	while (e[num_entries_filled - 1].tsc == 0) {
235 		num_entries_filled--;
236 	}
237 
238 	if (num_entries == num_entries_filled) {
239 		first = last = 0;
240 		for (i = 1; i < num_entries; i++) {
241 			if (e[i].tsc < e[first].tsc) {
242 				first = i;
243 			}
244 			if (e[i].tsc > e[last].tsc) {
245 				last = i;
246 			}
247 		}
248 	} else {
249 		first = 0;
250 		last = num_entries_filled - 1;
251 	}
252 
253 	/*
254 	 * We keep track of the highest first TSC out of all reactors.
255 	 *  We will ignore any events that occurred before this TSC on any
256 	 *  other reactors.  This will ensure we only print data for the
257 	 *  subset of time where we have data across all reactors.
258 	 */
259 	if (e[first].tsc > _tsc_offset) {
260 		_tsc_offset = e[first].tsc;
261 	}
262 
263 	i = first;
264 	while (1) {
265 		if (e[i].tpoint_id != SPDK_TRACE_MAX_TPOINT_ID) {
266 			_entries[entry_key(lcore, e[i].tsc)] = &e[i];
267 		}
268 		if (i == last) {
269 			break;
270 		}
271 		i++;
272 		if (i == num_entries_filled) {
273 			i = 0;
274 		}
275 	}
276 }
277 
278 bool
279 spdk_trace_parser::init(const spdk_trace_parser_opts *opts)
280 {
281 	spdk_trace_history *history;
282 	struct stat st;
283 	int rc, i;
284 
285 	switch (opts->mode) {
286 	case SPDK_TRACE_PARSER_MODE_FILE:
287 		_fd = open(opts->filename, O_RDONLY);
288 		break;
289 	case SPDK_TRACE_PARSER_MODE_SHM:
290 		_fd = shm_open(opts->filename, O_RDONLY, 0600);
291 		break;
292 	default:
293 		SPDK_ERRLOG("Invalid mode: %d\n", opts->mode);
294 		return false;
295 	}
296 
297 	if (_fd < 0) {
298 		SPDK_ERRLOG("Could not open trace file: %s (%d)\n", opts->filename, errno);
299 		return false;
300 	}
301 
302 	rc = fstat(_fd, &st);
303 	if (rc < 0) {
304 		SPDK_ERRLOG("Could not get size of trace file: %s\n", opts->filename);
305 		return false;
306 	}
307 
308 	if ((size_t)st.st_size < sizeof(*_histories)) {
309 		SPDK_ERRLOG("Invalid trace file: %s\n", opts->filename);
310 		return false;
311 	}
312 
313 	/* Map the header of trace file */
314 	_map_size = sizeof(*_histories);
315 	_histories = static_cast<spdk_trace_histories *>(mmap(NULL, _map_size, PROT_READ,
316 			MAP_SHARED, _fd, 0));
317 	if (_histories == MAP_FAILED) {
318 		SPDK_ERRLOG("Could not mmap trace file: %s\n", opts->filename);
319 		_histories = NULL;
320 		return false;
321 	}
322 
323 	/* Remap the entire trace file */
324 	_map_size = spdk_get_trace_histories_size(_histories);
325 	munmap(_histories, sizeof(*_histories));
326 	if ((size_t)st.st_size < _map_size) {
327 		SPDK_ERRLOG("Trace file %s is not valid\n", opts->filename);
328 		_histories = NULL;
329 		return false;
330 	}
331 	_histories = static_cast<spdk_trace_histories *>(mmap(NULL, _map_size, PROT_READ,
332 			MAP_SHARED, _fd, 0));
333 	if (_histories == MAP_FAILED) {
334 		SPDK_ERRLOG("Could not mmap trace file: %s\n", opts->filename);
335 		_histories = NULL;
336 		return false;
337 	}
338 
339 	if (opts->lcore == SPDK_TRACE_MAX_LCORE) {
340 		for (i = 0; i < SPDK_TRACE_MAX_LCORE; i++) {
341 			history = spdk_get_per_lcore_history(_histories, i);
342 			if (history == NULL || history->num_entries == 0 || history->entries[0].tsc == 0) {
343 				continue;
344 			}
345 
346 			populate_events(history, history->num_entries);
347 		}
348 	} else {
349 		history = spdk_get_per_lcore_history(_histories, opts->lcore);
350 		if (history == NULL) {
351 			SPDK_ERRLOG("Trace file %s has no trace history for lcore %d\n",
352 				    opts->filename, opts->lcore);
353 			return false;
354 		}
355 		if (history->num_entries > 0 && history->entries[0].tsc != 0) {
356 			populate_events(history, history->num_entries);
357 		}
358 	}
359 
360 	_iter = _entries.begin();
361 	return true;
362 }
363 
364 void
365 spdk_trace_parser::cleanup()
366 {
367 	if (_histories != NULL) {
368 		munmap(_histories, _map_size);
369 	}
370 
371 	if (_fd > 0) {
372 		close(_fd);
373 	}
374 }
375 
376 spdk_trace_parser::spdk_trace_parser(const spdk_trace_parser_opts *opts) :
377 	_histories(NULL),
378 	_map_size(0),
379 	_fd(-1),
380 	_tsc_offset(0)
381 {
382 	if (!init(opts)) {
383 		cleanup();
384 		throw std::exception();
385 	}
386 }
387 
388 spdk_trace_parser::~spdk_trace_parser()
389 {
390 	cleanup();
391 }
392 
393 struct spdk_trace_parser *
394 spdk_trace_parser_init(const struct spdk_trace_parser_opts *opts)
395 {
396 	try {
397 		return new spdk_trace_parser(opts);
398 	} catch (...) {
399 		return NULL;
400 	}
401 }
402 
403 void
404 spdk_trace_parser_cleanup(struct spdk_trace_parser *parser)
405 {
406 	delete parser;
407 }
408 
409 const struct spdk_trace_flags *
410 spdk_trace_parser_get_flags(const struct spdk_trace_parser *parser)
411 {
412 	return parser->flags();
413 }
414 
415 uint64_t
416 spdk_trace_parser_get_tsc_offset(const struct spdk_trace_parser *parser)
417 {
418 	return parser->tsc_offset();
419 }
420 
421 bool
422 spdk_trace_parser_next_entry(struct spdk_trace_parser *parser,
423 			     struct spdk_trace_parser_entry *entry)
424 {
425 	return parser->next_entry(entry);
426 }
427 
428 uint64_t
429 spdk_trace_parser_get_entry_count(const struct spdk_trace_parser *parser, uint16_t lcore)
430 {
431 	return parser->entry_count(lcore);
432 }
433