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