1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <string.h>
4
5 #include <linux/kernel.h>
6
7 #include "util/dso.h"
8 #include "util/util.h"
9 #include "util/debug.h"
10
11 #include "symbol.h"
12
13 bool srcline_full_filename;
14
15 #ifdef HAVE_LIBBFD_SUPPORT
16
17 /*
18 * Implement addr2line using libbfd.
19 */
20 #define PACKAGE "perf"
21 #include <bfd.h>
22
23 struct a2l_data {
24 const char *input;
25 u64 addr;
26
27 bool found;
28 const char *filename;
29 const char *funcname;
30 unsigned line;
31
32 bfd *abfd;
33 asymbol **syms;
34 };
35
bfd_error(const char * string)36 static int bfd_error(const char *string)
37 {
38 const char *errmsg;
39
40 errmsg = bfd_errmsg(bfd_get_error());
41 fflush(stdout);
42
43 if (string)
44 pr_debug("%s: %s\n", string, errmsg);
45 else
46 pr_debug("%s\n", errmsg);
47
48 return -1;
49 }
50
slurp_symtab(bfd * abfd,struct a2l_data * a2l)51 static int slurp_symtab(bfd *abfd, struct a2l_data *a2l)
52 {
53 long storage;
54 long symcount;
55 asymbol **syms;
56 bfd_boolean dynamic = FALSE;
57
58 if ((bfd_get_file_flags(abfd) & HAS_SYMS) == 0)
59 return bfd_error(bfd_get_filename(abfd));
60
61 storage = bfd_get_symtab_upper_bound(abfd);
62 if (storage == 0L) {
63 storage = bfd_get_dynamic_symtab_upper_bound(abfd);
64 dynamic = TRUE;
65 }
66 if (storage < 0L)
67 return bfd_error(bfd_get_filename(abfd));
68
69 syms = malloc(storage);
70 if (dynamic)
71 symcount = bfd_canonicalize_dynamic_symtab(abfd, syms);
72 else
73 symcount = bfd_canonicalize_symtab(abfd, syms);
74
75 if (symcount < 0) {
76 free(syms);
77 return bfd_error(bfd_get_filename(abfd));
78 }
79
80 a2l->syms = syms;
81 return 0;
82 }
83
find_address_in_section(bfd * abfd,asection * section,void * data)84 static void find_address_in_section(bfd *abfd, asection *section, void *data)
85 {
86 bfd_vma pc, vma;
87 bfd_size_type size;
88 struct a2l_data *a2l = data;
89 flagword flags;
90
91 if (a2l->found)
92 return;
93
94 #ifdef bfd_get_section_flags
95 flags = bfd_get_section_flags(abfd, section);
96 #else
97 flags = bfd_section_flags(section);
98 #endif
99 if ((flags & SEC_ALLOC) == 0)
100 return;
101
102 pc = a2l->addr;
103 #ifdef bfd_get_section_vma
104 vma = bfd_get_section_vma(abfd, section);
105 #else
106 vma = bfd_section_vma(section);
107 #endif
108 #ifdef bfd_get_section_size
109 size = bfd_get_section_size(section);
110 #else
111 size = bfd_section_size(section);
112 #endif
113
114 if (pc < vma || pc >= vma + size)
115 return;
116
117 a2l->found = bfd_find_nearest_line(abfd, section, a2l->syms, pc - vma,
118 &a2l->filename, &a2l->funcname,
119 &a2l->line);
120 }
121
addr2line_init(const char * path)122 static struct a2l_data *addr2line_init(const char *path)
123 {
124 bfd *abfd;
125 struct a2l_data *a2l = NULL;
126
127 abfd = bfd_openr(path, NULL);
128 if (abfd == NULL)
129 return NULL;
130
131 if (!bfd_check_format(abfd, bfd_object))
132 goto out;
133
134 a2l = zalloc(sizeof(*a2l));
135 if (a2l == NULL)
136 goto out;
137
138 a2l->abfd = abfd;
139 a2l->input = strdup(path);
140 if (a2l->input == NULL)
141 goto out;
142
143 if (slurp_symtab(abfd, a2l))
144 goto out;
145
146 return a2l;
147
148 out:
149 if (a2l) {
150 zfree((char **)&a2l->input);
151 free(a2l);
152 }
153 bfd_close(abfd);
154 return NULL;
155 }
156
addr2line_cleanup(struct a2l_data * a2l)157 static void addr2line_cleanup(struct a2l_data *a2l)
158 {
159 if (a2l->abfd)
160 bfd_close(a2l->abfd);
161 zfree((char **)&a2l->input);
162 zfree(&a2l->syms);
163 free(a2l);
164 }
165
166 #define MAX_INLINE_NEST 1024
167
addr2line(const char * dso_name,u64 addr,char ** file,unsigned int * line,struct dso * dso,bool unwind_inlines)168 static int addr2line(const char *dso_name, u64 addr,
169 char **file, unsigned int *line, struct dso *dso,
170 bool unwind_inlines)
171 {
172 int ret = 0;
173 struct a2l_data *a2l = dso->a2l;
174
175 if (!a2l) {
176 dso->a2l = addr2line_init(dso_name);
177 a2l = dso->a2l;
178 }
179
180 if (a2l == NULL) {
181 pr_warning("addr2line_init failed for %s\n", dso_name);
182 return 0;
183 }
184
185 a2l->addr = addr;
186 a2l->found = false;
187
188 bfd_map_over_sections(a2l->abfd, find_address_in_section, a2l);
189
190 if (a2l->found && unwind_inlines) {
191 int cnt = 0;
192
193 while (bfd_find_inliner_info(a2l->abfd, &a2l->filename,
194 &a2l->funcname, &a2l->line) &&
195 cnt++ < MAX_INLINE_NEST)
196 ;
197 }
198
199 if (a2l->found && a2l->filename) {
200 *file = strdup(a2l->filename);
201 *line = a2l->line;
202
203 if (*file)
204 ret = 1;
205 }
206
207 return ret;
208 }
209
dso__free_a2l(struct dso * dso)210 void dso__free_a2l(struct dso *dso)
211 {
212 struct a2l_data *a2l = dso->a2l;
213
214 if (!a2l)
215 return;
216
217 addr2line_cleanup(a2l);
218
219 dso->a2l = NULL;
220 }
221
222 #else /* HAVE_LIBBFD_SUPPORT */
223
addr2line(const char * dso_name,u64 addr,char ** file,unsigned int * line_nr,struct dso * dso __maybe_unused,bool unwind_inlines __maybe_unused)224 static int addr2line(const char *dso_name, u64 addr,
225 char **file, unsigned int *line_nr,
226 struct dso *dso __maybe_unused,
227 bool unwind_inlines __maybe_unused)
228 {
229 FILE *fp;
230 char cmd[PATH_MAX];
231 char *filename = NULL;
232 size_t len;
233 char *sep;
234 int ret = 0;
235
236 scnprintf(cmd, sizeof(cmd), "addr2line -e %s %016"PRIx64,
237 dso_name, addr);
238
239 fp = popen(cmd, "r");
240 if (fp == NULL) {
241 pr_warning("popen failed for %s\n", dso_name);
242 return 0;
243 }
244
245 if (getline(&filename, &len, fp) < 0 || !len) {
246 pr_warning("addr2line has no output for %s\n", dso_name);
247 goto out;
248 }
249
250 sep = strchr(filename, '\n');
251 if (sep)
252 *sep = '\0';
253
254 if (!strcmp(filename, "??:0")) {
255 pr_debug("no debugging info in %s\n", dso_name);
256 free(filename);
257 goto out;
258 }
259
260 sep = strchr(filename, ':');
261 if (sep) {
262 *sep++ = '\0';
263 *file = filename;
264 *line_nr = strtoul(sep, NULL, 0);
265 ret = 1;
266 }
267 out:
268 pclose(fp);
269 return ret;
270 }
271
dso__free_a2l(struct dso * dso __maybe_unused)272 void dso__free_a2l(struct dso *dso __maybe_unused)
273 {
274 }
275
276 #endif /* HAVE_LIBBFD_SUPPORT */
277
278 /*
279 * Number of addr2line failures (without success) before disabling it for that
280 * dso.
281 */
282 #define A2L_FAIL_LIMIT 123
283
__get_srcline(struct dso * dso,u64 addr,struct symbol * sym,bool show_sym,bool unwind_inlines)284 char *__get_srcline(struct dso *dso, u64 addr, struct symbol *sym,
285 bool show_sym, bool unwind_inlines)
286 {
287 char *file = NULL;
288 unsigned line = 0;
289 char *srcline;
290 const char *dso_name;
291
292 if (!dso->has_srcline)
293 goto out;
294
295 if (dso->symsrc_filename)
296 dso_name = dso->symsrc_filename;
297 else
298 dso_name = dso->long_name;
299
300 if (dso_name[0] == '[')
301 goto out;
302
303 if (!strncmp(dso_name, "/tmp/perf-", 10))
304 goto out;
305
306 if (!addr2line(dso_name, addr, &file, &line, dso, unwind_inlines))
307 goto out;
308
309 if (asprintf(&srcline, "%s:%u",
310 srcline_full_filename ? file : basename(file),
311 line) < 0) {
312 free(file);
313 goto out;
314 }
315
316 dso->a2l_fails = 0;
317
318 free(file);
319 return srcline;
320
321 out:
322 if (dso->a2l_fails && ++dso->a2l_fails > A2L_FAIL_LIMIT) {
323 dso->has_srcline = 0;
324 dso__free_a2l(dso);
325 }
326 if (sym) {
327 if (asprintf(&srcline, "%s+%" PRIu64, show_sym ? sym->name : "",
328 addr - sym->start) < 0)
329 return SRCLINE_UNKNOWN;
330 } else if (asprintf(&srcline, "%s[%" PRIx64 "]", dso->short_name, addr) < 0)
331 return SRCLINE_UNKNOWN;
332 return srcline;
333 }
334
free_srcline(char * srcline)335 void free_srcline(char *srcline)
336 {
337 if (srcline && strcmp(srcline, SRCLINE_UNKNOWN) != 0)
338 free(srcline);
339 }
340
get_srcline(struct dso * dso,u64 addr,struct symbol * sym,bool show_sym)341 char *get_srcline(struct dso *dso, u64 addr, struct symbol *sym,
342 bool show_sym)
343 {
344 return __get_srcline(dso, addr, sym, show_sym, false);
345 }
346