summaryrefslogtreecommitdiff
path: root/kernel/gcov/gcc_3_4.c
blob: d753d1152b7bfca84da9a84a98fbe78c5455d9fc (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
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
/*
 *  This code provides functions to handle gcc's profiling data format
 *  introduced with gcc 3.4. Future versions of gcc may change the gcov
 *  format (as happened before), so all format-specific information needs
 *  to be kept modular and easily exchangeable.
 *
 *  This file is based on gcc-internal definitions. Functions and data
 *  structures are defined to be compatible with gcc counterparts.
 *  For a better understanding, refer to gcc source: gcc/gcov-io.h.
 *
 *    Copyright IBM Corp. 2009
 *    Author(s): Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
 *
 *    Uses gcc-internal data definitions.
 */

#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/seq_file.h>
#include <linux/vmalloc.h>
#include "gcov.h"

/* Symbolic links to be created for each profiling data file. */
const struct gcov_link gcov_link[] = {
	{ OBJ_TREE, "gcno" },	/* Link to .gcno file in $(objtree). */
	{ 0, NULL},
};

/*
 * Determine whether a counter is active. Based on gcc magic. Doesn't change
 * at run-time.
 */
static int counter_active(struct gcov_info *info, unsigned int type)
{
	return (1 << type) & info->ctr_mask;
}

/* Determine number of active counters. Based on gcc magic. */
static unsigned int num_counter_active(struct gcov_info *info)
{
	unsigned int i;
	unsigned int result = 0;

	for (i = 0; i < GCOV_COUNTERS; i++) {
		if (counter_active(info, i))
			result++;
	}
	return result;
}

/**
 * gcov_info_reset - reset profiling data to zero
 * @info: profiling data set
 */
void gcov_info_reset(struct gcov_info *info)
{
	unsigned int active = num_counter_active(info);
	unsigned int i;

	for (i = 0; i < active; i++) {
		memset(info->counts[i].values, 0,
		       info->counts[i].num * sizeof(gcov_type));
	}
}

/**
 * gcov_info_is_compatible - check if profiling data can be added
 * @info1: first profiling data set
 * @info2: second profiling data set
 *
 * Returns non-zero if profiling data can be added, zero otherwise.
 */
int gcov_info_is_compatible(struct gcov_info *info1, struct gcov_info *info2)
{
	return (info1->stamp == info2->stamp);
}

/**
 * gcov_info_add - add up profiling data
 * @dest: profiling data set to which data is added
 * @source: profiling data set which is added
 *
 * Adds profiling counts of @source to @dest.
 */
void gcov_info_add(struct gcov_info *dest, struct gcov_info *source)
{
	unsigned int i;
	unsigned int j;

	for (i = 0; i < num_counter_active(dest); i++) {
		for (j = 0; j < dest->counts[i].num; j++) {
			dest->counts[i].values[j] +=
				source->counts[i].values[j];
		}
	}
}

/* Get size of function info entry. Based on gcc magic. */
static size_t get_fn_size(struct gcov_info *info)
{
	size_t size;

	size = sizeof(struct gcov_fn_info) + num_counter_active(info) *
	       sizeof(unsigned int);
	if (__alignof__(struct gcov_fn_info) > sizeof(unsigned int))
		size = ALIGN(size, __alignof__(struct gcov_fn_info));
	return size;
}

/* Get address of function info entry. Based on gcc magic. */
static struct gcov_fn_info *get_fn_info(struct gcov_info *info, unsigned int fn)
{
	return (struct gcov_fn_info *)
		((char *) info->functions + fn * get_fn_size(info));
}

/**
 * gcov_info_dup - duplicate profiling data set
 * @info: profiling data set to duplicate
 *
 * Return newly allocated duplicate on success, %NULL on error.
 */
struct gcov_info *gcov_info_dup(struct gcov_info *info)
{
	struct gcov_info *dup;
	unsigned int i;
	unsigned int active;

	/* Duplicate gcov_info. */
	active = num_counter_active(info);
	dup = kzalloc(sizeof(struct gcov_info) +
		      sizeof(struct gcov_ctr_info) * active, GFP_KERNEL);
	if (!dup)
		return NULL;
	dup->version		= info->version;
	dup->stamp		= info->stamp;
	dup->n_functions	= info->n_functions;
	dup->ctr_mask		= info->ctr_mask;
	/* Duplicate filename. */
	dup->filename		= kstrdup(info->filename, GFP_KERNEL);
	if (!dup->filename)
		goto err_free;
	/* Duplicate table of functions. */
	dup->functions = kmemdup(info->functions, info->n_functions *
				 get_fn_size(info), GFP_KERNEL);
	if (!dup->functions)
		goto err_free;
	/* Duplicate counter arrays. */
	for (i = 0; i < active ; i++) {
		struct gcov_ctr_info *ctr = &info->counts[i];
		size_t size = ctr->num * sizeof(gcov_type);

		dup->counts[i].num = ctr->num;
		dup->counts[i].merge = ctr->merge;
		dup->counts[i].values = vmalloc(size);
		if (!dup->counts[i].values)
			goto err_free;
		memcpy(dup->counts[i].values, ctr->values, size);
	}
	return dup;

err_free:
	gcov_info_free(dup);
	return NULL;
}

/**
 * gcov_info_free - release memory for profiling data set duplicate
 * @info: profiling data set duplicate to free
 */
void gcov_info_free(struct gcov_info *info)
{
	unsigned int active = num_counter_active(info);
	unsigned int i;

	for (i = 0; i < active ; i++)
		vfree(info->counts[i].values);
	kfree(info->functions);
	kfree(info->filename);
	kfree(info);
}

/**
 * struct type_info - iterator helper array
 * @ctr_type: counter type
 * @offset: index of the first value of the current function for this type
 *
 * This array is needed to convert the in-memory data format into the in-file
 * data format:
 *
 * In-memory:
 *   for each counter type
 *     for each function
 *       values
 *
 * In-file:
 *   for each function
 *     for each counter type
 *       values
 *
 * See gcc source gcc/gcov-io.h for more information on data organization.
 */
struct type_info {
	int ctr_type;
	unsigned int offset;
};

/**
 * struct gcov_iterator - specifies current file position in logical records
 * @info: associated profiling data
 * @record: record type
 * @function: function number
 * @type: counter type
 * @count: index into values array
 * @num_types: number of counter types
 * @type_info: helper array to get values-array offset for current function
 */
struct gcov_iterator {
	struct gcov_info *info;

	int record;
	unsigned int function;
	unsigned int type;
	unsigned int count;

	int num_types;
	struct type_info type_info[0];
};

static struct gcov_fn_info *get_func(struct gcov_iterator *iter)
{
	return get_fn_info(iter->info, iter->function);
}

static struct type_info *get_type(struct gcov_iterator *iter)
{
	return &iter->type_info[iter->type];
}

/**
 * gcov_iter_new - allocate and initialize profiling data iterator
 * @info: profiling data set to be iterated
 *
 * Return file iterator on success, %NULL otherwise.
 */
struct gcov_iterator *gcov_iter_new(struct gcov_info *info)
{
	struct gcov_iterator *iter;

	iter = kzalloc(sizeof(struct gcov_iterator) +
		       num_counter_active(info) * sizeof(struct type_info),
		       GFP_KERNEL);
	if (iter)
		iter->info = info;

	return iter;
}

/**
 * gcov_iter_free - release memory for iterator
 * @iter: file iterator to free
 */
void gcov_iter_free(struct gcov_iterator *iter)
{
	kfree(iter);
}

/**
 * gcov_iter_get_info - return profiling data set for given file iterator
 * @iter: file iterator
 */
struct gcov_info *gcov_iter_get_info(struct gcov_iterator *iter)
{
	return iter->info;
}

/**
 * gcov_iter_start - reset file iterator to starting position
 * @iter: file iterator
 */
void gcov_iter_start(struct gcov_iterator *iter)
{
	int i;

	iter->record = 0;
	iter->function = 0;
	iter->type = 0;
	iter->count = 0;
	iter->num_types = 0;
	for (i = 0; i < GCOV_COUNTERS; i++) {
		if (counter_active(iter->info, i)) {
			iter->type_info[iter->num_types].ctr_type = i;
			iter->type_info[iter->num_types++].offset = 0;
		}
	}
}

/* Mapping of logical record number to actual file content. */
#define RECORD_FILE_MAGIC		0
#define RECORD_GCOV_VERSION		1
#define RECORD_TIME_STAMP		2
#define RECORD_FUNCTION_TAG		3
#define RECORD_FUNCTON_TAG_LEN		4
#define RECORD_FUNCTION_IDENT		5
#define RECORD_FUNCTION_CHECK_LINE	6
#define RECORD_FUNCTION_CHECK_CFG	7
#define RECORD_FUNCTION_NAME_LEN	8
#define RECORD_FUNCTION_NAME		9
#define RECORD_COUNT_TAG		10
#define RECORD_COUNT_LEN		11
#define RECORD_COUNT			12

/* Return length of string encoded in GCOV format. */
static size_t
sizeof_str(const char *str)
{
	size_t len;
	len = (str) ? strlen(str) : 0;
	if (len == 0)
		return 1;
	return 1 + ((len + 4) >> 2);
}

/**
 * gcov_iter_next - advance file iterator to next logical record
 * @iter: file iterator
 *
 * Return zero if new position is valid, non-zero if iterator has reached end.
 */
int gcov_iter_next(struct gcov_iterator *iter)
{
	switch (iter->record) {
	case RECORD_FILE_MAGIC:
	case RECORD_GCOV_VERSION:
	case RECORD_FUNCTION_TAG:
	case RECORD_FUNCTON_TAG_LEN:
	case RECORD_FUNCTION_IDENT:
	case RECORD_COUNT_TAG:
	case RECORD_FUNCTION_CHECK_LINE:
	case RECORD_FUNCTION_CHECK_CFG:
	case RECORD_FUNCTION_NAME_LEN:
		/* Advance to next record */
		iter->record++;
		break;
	case RECORD_COUNT:
		/* Advance to next count */
		iter->count++;
		/* fall through */
	case RECORD_COUNT_LEN:
		if (iter->count < get_func(iter)->n_ctrs[iter->type]) {
			iter->record = 12;
			break;
		}
		/* Advance to next counter type */
		get_type(iter)->offset += iter->count;
		iter->count = 0;
		iter->type++;
		/* fall through */
	case RECORD_FUNCTION_NAME:
		if (iter->type < iter->num_types) {
			iter->record = 10;
			break;
		}
		/* Advance to next function */
		iter->type = 0;
		iter->function++;
		/* fall through */
	case RECORD_TIME_STAMP:
		if (iter->function < iter->info->n_functions)
			iter->record = 3;
		else
			iter->record = -1;
		break;
	}
	/* Check for EOF. */
	if (iter->record == -1)
		return -EINVAL;
	else
		return 0;
}

/**
 * seq_write_gcov_u32 - write 32 bit number in gcov format to seq_file
 * @seq: seq_file handle
 * @v: value to be stored
 *
 * Number format defined by gcc: numbers are recorded in the 32 bit
 * unsigned binary form of the endianness of the machine generating the
 * file.
 */
static int seq_write_gcov_u32(struct seq_file *seq, u32 v)
{
	return seq_write(seq, &v, sizeof(v));
}

/**
 * seq_write_gcov_u64 - write 64 bit number in gcov format to seq_file
 * @seq: seq_file handle
 * @v: value to be stored
 *
 * Number format defined by gcc: numbers are recorded in the 32 bit
 * unsigned binary form of the endianness of the machine generating the
 * file. 64 bit numbers are stored as two 32 bit numbers, the low part
 * first.
 */
static int seq_write_gcov_u64(struct seq_file *seq, u64 v)
{
	u32 data[2];

	data[0] = (v & 0xffffffffUL);
	data[1] = (v >> 32);
	return seq_write(seq, data, sizeof(data));
}
/**
 * seq_write_gcov_str - write string in gcov format to seq_file
 * @seq: seq_file handle
 * @str: string to be stored
 *
 * Number format defined by gcc: numbers are recorded in the 32 bit
 * unsigned binary form of the endianness of the machine generating the
 * file. 64 bit numbers are stored as two 32 bit numbers, the low part
 * first.
 */
static int seq_write_gcov_str(struct seq_file *seq, const char *str)
{
	if (str) {
		size_t len;
		int str_off;
		u32 data;
		len = strlen(str);
		for (str_off = 0; str_off < (sizeof_str(str) - 2) ; str_off++) {
			memcpy(&data, (str + str_off * 4), 4);
			seq_write(seq, &data, sizeof(data));
		}
		data = 0;
		memcpy(&data, (str + str_off * 4), (len - str_off * 4));
		return seq_write(seq, &data, sizeof(data));
	} else {
		return 0;
	}
}

/**
 * gcov_iter_write - write data for current pos to seq_file
 * @iter: file iterator
 * @seq: seq_file handle
 *
 * Return zero on success, non-zero otherwise.
 */
int gcov_iter_write(struct gcov_iterator *iter, struct seq_file *seq)
{
	int rc = -EINVAL;

	switch (iter->record) {
	case RECORD_FILE_MAGIC:
		rc = seq_write_gcov_u32(seq, GCOV_DATA_MAGIC);
		break;
	case RECORD_GCOV_VERSION:
		rc = seq_write_gcov_u32(seq, iter->info->version);
		break;
	case RECORD_TIME_STAMP:
		rc = seq_write_gcov_u32(seq, iter->info->stamp);
		break;
	case RECORD_FUNCTION_TAG:
		rc = seq_write_gcov_u32(seq, GCOV_TAG_FUNCTION);
		break;
	case RECORD_FUNCTON_TAG_LEN:
		rc = seq_write_gcov_u32(seq, GCOV_TAG_FUNCTION_LENGTH +
			(sizeof_str(get_func(iter)->name)));
		break;
	case RECORD_FUNCTION_IDENT:
		rc = seq_write_gcov_u32(seq, get_func(iter)->ident);
		break;
	case RECORD_FUNCTION_CHECK_LINE:
		rc = seq_write_gcov_u32(seq, get_func(iter)->lineno_checksum);
		break;
	case RECORD_FUNCTION_CHECK_CFG:
		rc = seq_write_gcov_u32(seq, get_func(iter)->cfg_checksum);
		break;
	case RECORD_FUNCTION_NAME_LEN:
		rc = seq_write_gcov_u32(seq,
			(sizeof_str(get_func(iter)->name) - 1));
		break;
	case RECORD_FUNCTION_NAME:
		rc = seq_write_gcov_str(seq, get_func(iter)->name);
		break;
	case RECORD_COUNT_TAG:
		rc = seq_write_gcov_u32(seq,
			GCOV_TAG_FOR_COUNTER(get_type(iter)->ctr_type));
		break;
	case RECORD_COUNT_LEN:
		rc = seq_write_gcov_u32(seq,
				get_func(iter)->n_ctrs[iter->type] * 2);
		break;
	case RECORD_COUNT:
		rc = seq_write_gcov_u64(seq,
			iter->info->counts[iter->type].
				values[iter->count + get_type(iter)->offset]);
		break;
	}
	return rc;
}