summaryrefslogtreecommitdiffstats
path: root/tools/perf/util/srcline.c
blob: e73b6a5c9e0fa8772862fdd3535701b67325c5dc (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
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <linux/kernel.h>

#include "util/dso.h"
#include "util/util.h"
#include "util/debug.h"

#include "symbol.h"

#ifdef HAVE_LIBBFD_SUPPORT

/*
 * Implement addr2line using libbfd.
 */
#define PACKAGE "perf"
#include <bfd.h>

struct a2l_data {
	const char 	*input;
	unsigned long 	addr;

	bool 		found;
	const char 	*filename;
	const char 	*funcname;
	unsigned 	line;

	bfd 		*abfd;
	asymbol 	**syms;
};

static int bfd_error(const char *string)
{
	const char *errmsg;

	errmsg = bfd_errmsg(bfd_get_error());
	fflush(stdout);

	if (string)
		pr_debug("%s: %s\n", string, errmsg);
	else
		pr_debug("%s\n", errmsg);

	return -1;
}

static int slurp_symtab(bfd *abfd, struct a2l_data *a2l)
{
	long storage;
	long symcount;
	asymbol **syms;
	bfd_boolean dynamic = FALSE;

	if ((bfd_get_file_flags(abfd) & HAS_SYMS) == 0)
		return bfd_error(bfd_get_filename(abfd));

	storage = bfd_get_symtab_upper_bound(abfd);
	if (storage == 0L) {
		storage = bfd_get_dynamic_symtab_upper_bound(abfd);
		dynamic = TRUE;
	}
	if (storage < 0L)
		return bfd_error(bfd_get_filename(abfd));

	syms = malloc(storage);
	if (dynamic)
		symcount = bfd_canonicalize_dynamic_symtab(abfd, syms);
	else
		symcount = bfd_canonicalize_symtab(abfd, syms);

	if (symcount < 0) {
		free(syms);
		return bfd_error(bfd_get_filename(abfd));
	}

	a2l->syms = syms;
	return 0;
}

static void find_address_in_section(bfd *abfd, asection *section, void *data)
{
	bfd_vma pc, vma;
	bfd_size_type size;
	struct a2l_data *a2l = data;

	if (a2l->found)
		return;

	if ((bfd_get_section_flags(abfd, section) & SEC_ALLOC) == 0)
		return;

	pc = a2l->addr;
	vma = bfd_get_section_vma(abfd, section);
	size = bfd_get_section_size(section);

	if (pc < vma || pc >= vma + size)
		return;

	a2l->found = bfd_find_nearest_line(abfd, section, a2l->syms, pc - vma,
					   &a2l->filename, &a2l->funcname,
					   &a2l->line);
}

static struct a2l_data *addr2line_init(const char *path)
{
	bfd *abfd;
	struct a2l_data *a2l = NULL;

	abfd = bfd_openr(path, NULL);
	if (abfd == NULL)
		return NULL;

	if (!bfd_check_format(abfd, bfd_object))
		goto out;

	a2l = zalloc(sizeof(*a2l));
	if (a2l == NULL)
		goto out;

	a2l->abfd = abfd;
	a2l->input = strdup(path);
	if (a2l->input == NULL)
		goto out;

	if (slurp_symtab(abfd, a2l))
		goto out;

	return a2l;

out:
	if (a2l) {
		zfree((char **)&a2l->input);
		free(a2l);
	}
	bfd_close(abfd);
	return NULL;
}

static void addr2line_cleanup(struct a2l_data *a2l)
{
	if (a2l->abfd)
		bfd_close(a2l->abfd);
	zfree((char **)&a2l->input);
	zfree(&a2l->syms);
	free(a2l);
}

static int addr2line(const char *dso_name, unsigned long addr,
		     char **file, unsigned int *line, struct dso *dso)
{
	int ret = 0;
	struct a2l_data *a2l = dso->a2l;

	if (!a2l) {
		dso->a2l = addr2line_init(dso_name);
		a2l = dso->a2l;
	}

	if (a2l == NULL) {
		pr_warning("addr2line_init failed for %s\n", dso_name);
		return 0;
	}

	a2l->addr = addr;
	a2l->found = false;

	bfd_map_over_sections(a2l->abfd, find_address_in_section, a2l);

	if (a2l->found && a2l->filename) {
		*file = strdup(a2l->filename);
		*line = a2l->line;

		if (*file)
			ret = 1;
	}

	return ret;
}

void dso__free_a2l(struct dso *dso)
{
	struct a2l_data *a2l = dso->a2l;

	if (!a2l)
		return;

	addr2line_cleanup(a2l);

	dso->a2l = NULL;
}

#else /* HAVE_LIBBFD_SUPPORT */

static int addr2line(const char *dso_name, unsigned long addr,
		     char **file, unsigned int *line_nr,
		     struct dso *dso __maybe_unused)
{
	FILE *fp;
	char cmd[PATH_MAX];
	char *filename = NULL;
	size_t len;
	char *sep;
	int ret = 0;

	scnprintf(cmd, sizeof(cmd), "addr2line -e %s %016"PRIx64,
		  dso_name, addr);

	fp = popen(cmd, "r");
	if (fp == NULL) {
		pr_warning("popen failed for %s\n", dso_name);
		return 0;
	}

	if (getline(&filename, &len, fp) < 0 || !len) {
		pr_warning("addr2line has no output for %s\n", dso_name);
		goto out;
	}

	sep = strchr(filename, '\n');
	if (sep)
		*sep = '\0';

	if (!strcmp(filename, "??:0")) {
		pr_debug("no debugging info in %s\n", dso_name);
		free(filename);
		goto out;
	}

	sep = strchr(filename, ':');
	if (sep) {
		*sep++ = '\0';
		*file = filename;
		*line_nr = strtoul(sep, NULL, 0);
		ret = 1;
	}
out:
	pclose(fp);
	return ret;
}

void dso__free_a2l(struct dso *dso __maybe_unused)
{
}

#endif /* HAVE_LIBBFD_SUPPORT */

/*
 * Number of addr2line failures (without success) before disabling it for that
 * dso.
 */
#define A2L_FAIL_LIMIT 123

char *get_srcline(struct dso *dso, unsigned long addr, struct symbol *sym,
		  bool show_sym)
{
	char *file = NULL;
	unsigned line = 0;
	char *srcline;
	const char *dso_name;

	if (!dso->has_srcline)
		goto out;

	if (dso->symsrc_filename)
		dso_name = dso->symsrc_filename;
	else
		dso_name = dso->long_name;

	if (dso_name[0] == '[')
		goto out;

	if (!strncmp(dso_name, "/tmp/perf-", 10))
		goto out;

	if (!addr2line(dso_name, addr, &file, &line, dso))
		goto out;

	if (asprintf(&srcline, "%s:%u", basename(file), line) < 0) {
		free(file);
		goto out;
	}

	dso->a2l_fails = 0;

	free(file);
	return srcline;

out:
	if (dso->a2l_fails && ++dso->a2l_fails > A2L_FAIL_LIMIT) {
		dso->has_srcline = 0;
		dso__free_a2l(dso);
	}
	if (sym) {
		if (asprintf(&srcline, "%s+%ld", show_sym ? sym->name : "",
					addr - sym->start) < 0)
			return SRCLINE_UNKNOWN;
	} else if (asprintf(&srcline, "%s[%lx]", dso->short_name, addr) < 0)
		return SRCLINE_UNKNOWN;
	return srcline;
}

void free_srcline(char *srcline)
{
	if (srcline && strcmp(srcline, SRCLINE_UNKNOWN) != 0)
		free(srcline);
}
OpenPOWER on IntegriCloud