aboutsummaryrefslogtreecommitdiff
path: root/tools/perf/util/session.c
blob: 736d4fda9272a552bcc29a798b82f3933228845a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
#include <linux/kernel.h>

#include <unistd.h>
#include <sys/types.h>

#include "session.h"
#include "sort.h"
#include "util.h"

static int perf_session__open(struct perf_session *self, bool force)
{
	struct stat input_stat;

	self->fd = open(self->filename, O_RDONLY);
	if (self->fd < 0) {
		pr_err("failed to open file: %s", self->filename);
		if (!strcmp(self->filename, "perf.data"))
			pr_err("  (try 'perf record' first)");
		pr_err("\n");
		return -errno;
	}

	if (fstat(self->fd, &input_stat) < 0)
		goto out_close;

	if (!force && input_stat.st_uid && (input_stat.st_uid != geteuid())) {
		pr_err("file %s not owned by current user or root\n",
		       self->filename);
		goto out_close;
	}

	if (!input_stat.st_size) {
		pr_info("zero-sized file (%s), nothing to do!\n",
			self->filename);
		goto out_close;
	}

	if (perf_header__read(&self->header, self->fd) < 0) {
		pr_err("incompatible file format");
		goto out_close;
	}

	self->size = input_stat.st_size;
	return 0;

out_close:
	close(self->fd);
	self->fd = -1;
	return -1;
}

struct perf_session *perf_session__new(const char *filename, int mode, bool force)
{
	size_t len = filename ? strlen(filename) + 1 : 0;
	struct perf_session *self = zalloc(sizeof(*self) + len);

	if (self == NULL)
		goto out;

	if (perf_header__init(&self->header) < 0)
		goto out_free;

	memcpy(self->filename, filename, len);
	self->threads = RB_ROOT;
	self->last_match = NULL;
	self->mmap_window = 32;
	self->cwd = NULL;
	self->cwdlen = 0;
	map_groups__init(&self->kmaps);

	if (perf_session__create_kernel_maps(self) < 0)
		goto out_delete;

	if (mode == O_RDONLY && perf_session__open(self, force) < 0)
		goto out_delete;
out:
	return self;
out_free:
	free(self);
	return NULL;
out_delete:
	perf_session__delete(self);
	return NULL;
}

void perf_session__delete(struct perf_session *self)
{
	perf_header__exit(&self->header);
	close(self->fd);
	free(self->cwd);
	free(self);
}

static bool symbol__match_parent_regex(struct symbol *sym)
{
	if (sym->name && !regexec(&parent_regex, sym->name, 0, NULL, 0))
		return 1;

	return 0;
}

struct symbol **perf_session__resolve_callchain(struct perf_session *self,
						struct thread *thread,
						struct ip_callchain *chain,
						struct symbol **parent)
{
	u8 cpumode = PERF_RECORD_MISC_USER;
	struct symbol **syms = NULL;
	unsigned int i;

	if (symbol_conf.use_callchain) {
		syms = calloc(chain->nr, sizeof(*syms));
		if (!syms) {
			fprintf(stderr, "Can't allocate memory for symbols\n");
			exit(-1);
		}
	}

	for (i = 0; i < chain->nr; i++) {
		u64 ip = chain->ips[i];
		struct addr_location al;

		if (ip >= PERF_CONTEXT_MAX) {
			switch (ip) {
			case PERF_CONTEXT_HV:
				cpumode = PERF_RECORD_MISC_HYPERVISOR;	break;
			case PERF_CONTEXT_KERNEL:
				cpumode = PERF_RECORD_MISC_KERNEL;	break;
			case PERF_CONTEXT_USER:
				cpumode = PERF_RECORD_MISC_USER;	break;
			default:
				break;
			}
			continue;
		}

		thread__find_addr_location(thread, self, cpumode,
					   MAP__FUNCTION, ip, &al, NULL);
		if (al.sym != NULL) {
			if (sort__has_parent && !*parent &&
			    symbol__match_parent_regex(al.sym))
				*parent = al.sym;
			if (!symbol_conf.use_callchain)
				break;
			syms[i] = al.sym;
		}
	}

	return syms;
}

static int process_event_stub(event_t *event __used,
			      struct perf_session *session __used)
{
	dump_printf(": unhandled!\n");
	return 0;
}

static void perf_event_ops__fill_defaults(struct perf_event_ops *handler)
{
	if (handler->process_sample_event == NULL)
		handler->process_sample_event = process_event_stub;
	if (handler->process_mmap_event == NULL)
		handler->process_mmap_event = process_event_stub;
	if (handler->process_comm_event == NULL)
		handler->process_comm_event = process_event_stub;
	if (handler->process_fork_event == NULL)
		handler->process_fork_event = process_event_stub;
	if (handler->process_exit_event == NULL)
		handler->process_exit_event = process_event_stub;
	if (handler->process_lost_event == NULL)
		handler->process_lost_event = process_event_stub;
	if (handler->process_read_event == NULL)
		handler->process_read_event = process_event_stub;
	if (handler->process_throttle_event == NULL)
		handler->process_throttle_event = process_event_stub;
	if (handler->process_unthrottle_event == NULL)
		handler->process_unthrottle_event = process_event_stub;
}

static const char *event__name[] = {
	[0]			 = "TOTAL",
	[PERF_RECORD_MMAP]	 = "MMAP",
	[PERF_RECORD_LOST]	 = "LOST",
	[PERF_RECORD_COMM]	 = "COMM",
	[PERF_RECORD_EXIT]	 = "EXIT",
	[PERF_RECORD_THROTTLE]	 = "THROTTLE",
	[PERF_RECORD_UNTHROTTLE] = "UNTHROTTLE",
	[PERF_RECORD_FORK]	 = "FORK",
	[PERF_RECORD_READ]	 = "READ",
	[PERF_RECORD_SAMPLE]	 = "SAMPLE",
};

unsigned long event__total[PERF_RECORD_MAX];

void event__print_totals(void)
{
	int i;
	for (i = 0; i < PERF_RECORD_MAX; ++i)
		pr_info("%10s events: %10ld\n",
			event__name[i], event__total[i]);
}

static int perf_session__process_event(struct perf_session *self,
				       event_t *event,
				       struct perf_event_ops *ops,
				       unsigned long offset, unsigned long head)
{
	trace_event(event);

	if (event->header.type < PERF_RECORD_MAX) {
		dump_printf("%p [%p]: PERF_RECORD_%s",
			    (void *)(offset + head),
			    (void *)(long)(event->header.size),
			    event__name[event->header.type]);
		++event__total[0];
		++event__total[event->header.type];
	}

	switch (event->header.type) {
	case PERF_RECORD_SAMPLE:
		return ops->process_sample_event(event, self);
	case PERF_RECORD_MMAP:
		return ops->process_mmap_event(event, self);
	case PERF_RECORD_COMM:
		return ops->process_comm_event(event, self);
	case PERF_RECORD_FORK:
		return ops->process_fork_event(event, self);
	case PERF_RECORD_EXIT:
		return ops->process_exit_event(event, self);
	case PERF_RECORD_LOST:
		return ops->process_lost_event(event, self);
	case PERF_RECORD_READ:
		return ops->process_read_event(event, self);
	case PERF_RECORD_THROTTLE:
		return ops->process_throttle_event(event, self);
	case PERF_RECORD_UNTHROTTLE:
		return ops->process_unthrottle_event(event, self);
	default:
		ops->total_unknown++;
		return -1;
	}
}

int perf_header__read_build_ids(int input, u64 offset, u64 size)
{
	struct build_id_event bev;
	char filename[PATH_MAX];
	u64 limit = offset + size;
	int err = -1;

	while (offset < limit) {
		struct dso *dso;
		ssize_t len;

		if (read(input, &bev, sizeof(bev)) != sizeof(bev))
			goto out;

		len = bev.header.size - sizeof(bev);
		if (read(input, filename, len) != len)
			goto out;

		dso = dsos__findnew(filename);
		if (dso != NULL)
			dso__set_build_id(dso, &bev.build_id);

		offset += bev.header.size;
	}
	err = 0;
out:
	return err;
}

static struct thread *perf_session__register_idle_thread(struct perf_session *self)
{
	struct thread *thread = perf_session__findnew(self, 0);

	if (thread == NULL || thread__set_comm(thread, "swapper")) {
		pr_err("problem inserting idle task.\n");
		thread = NULL;
	}

	return thread;
}

int perf_session__process_events(struct perf_session *self,
				 struct perf_event_ops *ops)
{
	int err;
	unsigned long head, shift;
	unsigned long offset = 0;
	size_t	page_size;
	event_t *event;
	uint32_t size;
	char *buf;

	if (perf_session__register_idle_thread(self) == NULL)
		return -ENOMEM;

	perf_event_ops__fill_defaults(ops);

	page_size = getpagesize();

	head = self->header.data_offset;
	self->sample_type = perf_header__sample_type(&self->header);

	err = -EINVAL;
	if (ops->sample_type_check && ops->sample_type_check(self) < 0)
		goto out_err;

	if (!ops->full_paths) {
		char bf[PATH_MAX];

		if (getcwd(bf, sizeof(bf)) == NULL) {
			err = -errno;
out_getcwd_err:
			pr_err("failed to get the current directory\n");
			goto out_err;
		}
		self->cwd = strdup(bf);
		if (self->cwd == NULL) {
			err = -ENOMEM;
			goto out_getcwd_err;
		}
		self->cwdlen = strlen(self->cwd);
	}

	shift = page_size * (head / page_size);
	offset += shift;
	head -= shift;

remap:
	buf = mmap(NULL, page_size * self->mmap_window, PROT_READ,
		   MAP_SHARED, self->fd, offset);
	if (buf == MAP_FAILED) {
		pr_err("failed to mmap file\n");
		err = -errno;
		goto out_err;
	}

more:
	event = (event_t *)(buf + head);

	size = event->header.size;
	if (size == 0)
		size = 8;

	if (head + event->header.size >= page_size * self->mmap_window) {
		int munmap_ret;

		shift = page_size * (head / page_size);

		munmap_ret = munmap(buf, page_size * self->mmap_window);
		assert(munmap_ret == 0);

		offset += shift;
		head -= shift;
		goto remap;
	}

	size = event->header.size;

	dump_printf("\n%p [%p]: event: %d\n",
			(void *)(offset + head),
			(void *)(long)event->header.size,
			event->header.type);

	if (size == 0 ||
	    perf_session__process_event(self, event, ops, offset, head) < 0) {
		dump_printf("%p [%p]: skipping unknown header type: %d\n",
			    (void *)(offset + head),
			    (void *)(long)(event->header.size),
			    event->header.type);
		/*
		 * assume we lost track of the stream, check alignment, and
		 * increment a single u64 in the hope to catch on again 'soon'.
		 */
		if (unlikely(head & 7))
			head &= ~7ULL;

		size = 8;
	}

	head += size;

	if (offset + head >= self->header.data_offset + self->header.data_size)
		goto done;

	if (offset + head < self->size)
		goto more;
done:
	err = 0;
out_err:
	return err;
}