summaryrefslogtreecommitdiffstats
path: root/tools/perf/util/header.c
blob: 7d26659b806c5cbb7eb00f0847ee83069df4db74 (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 <sys/types.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>

#include "util.h"
#include "header.h"
#include "../perf.h"
#include "trace-event.h"

/*
 * Create new perf.data header attribute:
 */
struct perf_header_attr *perf_header_attr__new(struct perf_event_attr *attr)
{
	struct perf_header_attr *self = malloc(sizeof(*self));

	if (!self)
		die("nomem");

	self->attr = *attr;
	self->ids = 0;
	self->size = 1;
	self->id = malloc(sizeof(u64));

	if (!self->id)
		die("nomem");

	return self;
}

void perf_header_attr__add_id(struct perf_header_attr *self, u64 id)
{
	int pos = self->ids;

	self->ids++;
	if (self->ids > self->size) {
		self->size *= 2;
		self->id = realloc(self->id, self->size * sizeof(u64));
		if (!self->id)
			die("nomem");
	}
	self->id[pos] = id;
}

/*
 * Create new perf.data header:
 */
struct perf_header *perf_header__new(void)
{
	struct perf_header *self = calloc(sizeof(*self), 1);

	if (!self)
		die("nomem");

	self->size = 1;
	self->attr = malloc(sizeof(void *));

	if (!self->attr)
		die("nomem");

	return self;
}

void perf_header__add_attr(struct perf_header *self,
			   struct perf_header_attr *attr)
{
	int pos = self->attrs;

	if (self->frozen)
		die("frozen");

	self->attrs++;
	if (self->attrs > self->size) {
		self->size *= 2;
		self->attr = realloc(self->attr, self->size * sizeof(void *));
		if (!self->attr)
			die("nomem");
	}
	self->attr[pos] = attr;
}

#define MAX_EVENT_NAME 64

struct perf_trace_event_type {
	u64	event_id;
	char	name[MAX_EVENT_NAME];
};

static int event_count;
static struct perf_trace_event_type *events;

void perf_header__push_event(u64 id, const char *name)
{
	if (strlen(name) > MAX_EVENT_NAME)
		pr_warning("Event %s will be truncated\n", name);

	if (!events) {
		events = malloc(sizeof(struct perf_trace_event_type));
		if (!events)
			die("nomem");
	} else {
		events = realloc(events, (event_count + 1) * sizeof(struct perf_trace_event_type));
		if (!events)
			die("nomem");
	}
	memset(&events[event_count], 0, sizeof(struct perf_trace_event_type));
	events[event_count].event_id = id;
	strncpy(events[event_count].name, name, MAX_EVENT_NAME - 1);
	event_count++;
}

char *perf_header__find_event(u64 id)
{
	int i;
	for (i = 0 ; i < event_count; i++) {
		if (events[i].event_id == id)
			return events[i].name;
	}
	return NULL;
}

static const char *__perf_magic = "PERFFILE";

#define PERF_MAGIC	(*(u64 *)__perf_magic)

struct perf_file_section {
	u64 offset;
	u64 size;
};

struct perf_file_attr {
	struct perf_event_attr	attr;
	struct perf_file_section	ids;
};

struct perf_file_header {
	u64				magic;
	u64				size;
	u64				attr_size;
	struct perf_file_section	attrs;
	struct perf_file_section	data;
	struct perf_file_section	event_types;
	DECLARE_BITMAP(adds_features, HEADER_FEAT_BITS);
};

void perf_header__feat_trace_info(struct perf_header *header)
{
	set_bit(HEADER_TRACE_INFO, header->adds_features);
}

static void do_write(int fd, void *buf, size_t size)
{
	while (size) {
		int ret = write(fd, buf, size);

		if (ret < 0)
			die("failed to write");

		size -= ret;
		buf += ret;
	}
}

static void perf_header__adds_write(struct perf_header *self, int fd)
{
	struct perf_file_section trace_sec;
	u64 cur_offset = lseek(fd, 0, SEEK_CUR);
	unsigned long *feat_mask = self->adds_features;

	if (test_bit(HEADER_TRACE_INFO, feat_mask)) {
		/* Write trace info */
		trace_sec.offset = lseek(fd, sizeof(trace_sec), SEEK_CUR);
		read_tracing_data(fd, attrs, nr_counters);
		trace_sec.size = lseek(fd, 0, SEEK_CUR) - trace_sec.offset;

		/* Write trace info headers */
		lseek(fd, cur_offset, SEEK_SET);
		do_write(fd, &trace_sec, sizeof(trace_sec));

		/*
		 * Update cur_offset. So that other (future)
		 * features can set their own infos in this place. But if we are
		 * the only feature, at least that seeks to the place the data
		 * should begin.
		 */
		cur_offset = lseek(fd, trace_sec.offset + trace_sec.size, SEEK_SET);
	}
};

void perf_header__write(struct perf_header *self, int fd)
{
	struct perf_file_header f_header;
	struct perf_file_attr   f_attr;
	struct perf_header_attr	*attr;
	int i;

	lseek(fd, sizeof(f_header), SEEK_SET);


	for (i = 0; i < self->attrs; i++) {
		attr = self->attr[i];

		attr->id_offset = lseek(fd, 0, SEEK_CUR);
		do_write(fd, attr->id, attr->ids * sizeof(u64));
	}


	self->attr_offset = lseek(fd, 0, SEEK_CUR);

	for (i = 0; i < self->attrs; i++) {
		attr = self->attr[i];

		f_attr = (struct perf_file_attr){
			.attr = attr->attr,
			.ids  = {
				.offset = attr->id_offset,
				.size   = attr->ids * sizeof(u64),
			}
		};
		do_write(fd, &f_attr, sizeof(f_attr));
	}

	self->event_offset = lseek(fd, 0, SEEK_CUR);
	self->event_size = event_count * sizeof(struct perf_trace_event_type);
	if (events)
		do_write(fd, events, self->event_size);

	perf_header__adds_write(self, fd);

	self->data_offset = lseek(fd, 0, SEEK_CUR);

	f_header = (struct perf_file_header){
		.magic	   = PERF_MAGIC,
		.size	   = sizeof(f_header),
		.attr_size = sizeof(f_attr),
		.attrs = {
			.offset = self->attr_offset,
			.size   = self->attrs * sizeof(f_attr),
		},
		.data = {
			.offset = self->data_offset,
			.size	= self->data_size,
		},
		.event_types = {
			.offset = self->event_offset,
			.size	= self->event_size,
		},
	};

	memcpy(&f_header.adds_features, &self->adds_features, sizeof(self->adds_features));

	lseek(fd, 0, SEEK_SET);
	do_write(fd, &f_header, sizeof(f_header));
	lseek(fd, self->data_offset + self->data_size, SEEK_SET);

	self->frozen = 1;
}

static void do_read(int fd, void *buf, size_t size)
{
	while (size) {
		int ret = read(fd, buf, size);

		if (ret < 0)
			die("failed to read");
		if (ret == 0)
			die("failed to read: missing data");

		size -= ret;
		buf += ret;
	}
}

static void perf_header__adds_read(struct perf_header *self, int fd)
{
	const unsigned long *feat_mask = self->adds_features;

	if (test_bit(HEADER_TRACE_INFO, feat_mask)) {
		struct perf_file_section trace_sec;

		do_read(fd, &trace_sec, sizeof(trace_sec));
		lseek(fd, trace_sec.offset, SEEK_SET);
		trace_report(fd);
		lseek(fd, trace_sec.offset + trace_sec.size, SEEK_SET);
	}
};

struct perf_header *perf_header__read(int fd)
{
	struct perf_header	*self = perf_header__new();
	struct perf_file_header f_header;
	struct perf_file_attr	f_attr;
	u64			f_id;

	int nr_attrs, nr_ids, i, j;

	lseek(fd, 0, SEEK_SET);
	do_read(fd, &f_header, sizeof(f_header));

	if (f_header.magic	!= PERF_MAGIC		||
	    f_header.attr_size	!= sizeof(f_attr))
		die("incompatible file format");

	if (f_header.size != sizeof(f_header)) {
		/* Support the previous format */
		if (f_header.size == offsetof(typeof(f_header), adds_features))
			bitmap_zero(f_header.adds_features, HEADER_FEAT_BITS);
		else
			die("incompatible file format");
	}
	nr_attrs = f_header.attrs.size / sizeof(f_attr);
	lseek(fd, f_header.attrs.offset, SEEK_SET);

	for (i = 0; i < nr_attrs; i++) {
		struct perf_header_attr *attr;
		off_t tmp;

		do_read(fd, &f_attr, sizeof(f_attr));
		tmp = lseek(fd, 0, SEEK_CUR);

		attr = perf_header_attr__new(&f_attr.attr);

		nr_ids = f_attr.ids.size / sizeof(u64);
		lseek(fd, f_attr.ids.offset, SEEK_SET);

		for (j = 0; j < nr_ids; j++) {
			do_read(fd, &f_id, sizeof(f_id));

			perf_header_attr__add_id(attr, f_id);
		}
		perf_header__add_attr(self, attr);
		lseek(fd, tmp, SEEK_SET);
	}

	if (f_header.event_types.size) {
		lseek(fd, f_header.event_types.offset, SEEK_SET);
		events = malloc(f_header.event_types.size);
		if (!events)
			die("nomem");
		do_read(fd, events, f_header.event_types.size);
		event_count =  f_header.event_types.size / sizeof(struct perf_trace_event_type);
	}

	memcpy(&self->adds_features, &f_header.adds_features, sizeof(f_header.adds_features));

	perf_header__adds_read(self, fd);

	self->event_offset = f_header.event_types.offset;
	self->event_size   = f_header.event_types.size;

	self->data_offset = f_header.data.offset;
	self->data_size   = f_header.data.size;

	lseek(fd, self->data_offset, SEEK_SET);

	self->frozen = 1;

	return self;
}

u64 perf_header__sample_type(struct perf_header *header)
{
	u64 type = 0;
	int i;

	for (i = 0; i < header->attrs; i++) {
		struct perf_header_attr *attr = header->attr[i];

		if (!type)
			type = attr->attr.sample_type;
		else if (type != attr->attr.sample_type)
			die("non matching sample_type");
	}

	return type;
}

struct perf_event_attr *
perf_header__find_attr(u64 id, struct perf_header *header)
{
	int i;

	for (i = 0; i < header->attrs; i++) {
		struct perf_header_attr *attr = header->attr[i];
		int j;

		for (j = 0; j < attr->ids; j++) {
			if (attr->id[j] == id)
				return &attr->attr;
		}
	}

	return NULL;
}
OpenPOWER on IntegriCloud