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4ea42b18 MH |
1 | /* |
2 | * probe-finder.c : C expression to kprobe event converter | |
3 | * | |
4 | * Written by Masami Hiramatsu <mhiramat@redhat.com> | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License as published by | |
8 | * the Free Software Foundation; either version 2 of the License, or | |
9 | * (at your option) any later version. | |
10 | * | |
11 | * This program is distributed in the hope that it will be useful, | |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | * GNU General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * along with this program; if not, write to the Free Software | |
18 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
19 | * | |
20 | */ | |
21 | ||
22 | #include <sys/utsname.h> | |
23 | #include <sys/types.h> | |
24 | #include <sys/stat.h> | |
25 | #include <fcntl.h> | |
26 | #include <errno.h> | |
27 | #include <stdio.h> | |
28 | #include <unistd.h> | |
29 | #include <getopt.h> | |
30 | #include <stdlib.h> | |
31 | #include <string.h> | |
32 | #include <stdarg.h> | |
33 | #include <ctype.h> | |
34 | #include "probe-finder.h" | |
35 | ||
36 | ||
37 | /* Dwarf_Die Linkage to parent Die */ | |
38 | struct die_link { | |
39 | struct die_link *parent; /* Parent die */ | |
40 | Dwarf_Die die; /* Current die */ | |
41 | }; | |
42 | ||
43 | static Dwarf_Debug __dw_debug; | |
44 | static Dwarf_Error __dw_error; | |
45 | ||
46 | static void msg_exit(int ret, const char *fmt, ...) | |
47 | { | |
48 | va_list ap; | |
49 | ||
50 | va_start(ap, fmt); | |
51 | fprintf(stderr, "Error: "); | |
52 | vfprintf(stderr, fmt, ap); | |
53 | va_end(ap); | |
54 | ||
55 | fprintf(stderr, "\n"); | |
56 | exit(ret); | |
57 | } | |
58 | ||
59 | ||
60 | /* | |
61 | * Generic dwarf analysis helpers | |
62 | */ | |
63 | ||
64 | #define X86_32_MAX_REGS 8 | |
65 | const char *x86_32_regs_table[X86_32_MAX_REGS] = { | |
66 | "%ax", | |
67 | "%cx", | |
68 | "%dx", | |
69 | "%bx", | |
70 | "$stack", /* Stack address instead of %sp */ | |
71 | "%bp", | |
72 | "%si", | |
73 | "%di", | |
74 | }; | |
75 | ||
76 | #define X86_64_MAX_REGS 16 | |
77 | const char *x86_64_regs_table[X86_64_MAX_REGS] = { | |
78 | "%ax", | |
79 | "%dx", | |
80 | "%cx", | |
81 | "%bx", | |
82 | "%si", | |
83 | "%di", | |
84 | "%bp", | |
85 | "%sp", | |
86 | "%r8", | |
87 | "%r9", | |
88 | "%r10", | |
89 | "%r11", | |
90 | "%r12", | |
91 | "%r13", | |
92 | "%r14", | |
93 | "%r15", | |
94 | }; | |
95 | ||
96 | /* TODO: switching by dwarf address size */ | |
97 | #ifdef __x86_64__ | |
98 | #define ARCH_MAX_REGS X86_64_MAX_REGS | |
99 | #define arch_regs_table x86_64_regs_table | |
100 | #else | |
101 | #define ARCH_MAX_REGS X86_32_MAX_REGS | |
102 | #define arch_regs_table x86_32_regs_table | |
103 | #endif | |
104 | ||
105 | /* Return architecture dependent register string (for kprobe-tracer) */ | |
106 | static const char *get_arch_regstr(unsigned int n) | |
107 | { | |
108 | return (n <= ARCH_MAX_REGS) ? arch_regs_table[n] : NULL; | |
109 | } | |
110 | ||
111 | /* | |
112 | * Compare the tail of two strings. | |
113 | * Return 0 if whole of either string is same as another's tail part. | |
114 | */ | |
115 | static int strtailcmp(const char *s1, const char *s2) | |
116 | { | |
117 | int i1 = strlen(s1); | |
118 | int i2 = strlen(s2); | |
119 | while (--i1 > 0 && --i2 > 0) { | |
120 | if (s1[i1] != s2[i2]) | |
121 | return s1[i1] - s2[i2]; | |
122 | } | |
123 | return 0; | |
124 | } | |
125 | ||
126 | /* Find the fileno of the target file. */ | |
127 | static Dwarf_Unsigned die_get_fileno(Dwarf_Die cu_die, const char *fname) | |
128 | { | |
129 | Dwarf_Signed cnt, i; | |
130 | Dwarf_Unsigned found = 0; | |
131 | char **srcs; | |
132 | int ret; | |
133 | ||
134 | if (!fname) | |
135 | return 0; | |
136 | ||
137 | ret = dwarf_srcfiles(cu_die, &srcs, &cnt, &__dw_error); | |
138 | if (ret == DW_DLV_OK) { | |
139 | for (i = 0; i < cnt && !found; i++) { | |
140 | if (strtailcmp(srcs[i], fname) == 0) | |
141 | found = i + 1; | |
142 | dwarf_dealloc(__dw_debug, srcs[i], DW_DLA_STRING); | |
143 | } | |
144 | for (; i < cnt; i++) | |
145 | dwarf_dealloc(__dw_debug, srcs[i], DW_DLA_STRING); | |
146 | dwarf_dealloc(__dw_debug, srcs, DW_DLA_LIST); | |
147 | } | |
148 | if (found) | |
149 | debug("found fno: %d\n", (int)found); | |
150 | return found; | |
151 | } | |
152 | ||
153 | /* Compare diename and tname */ | |
154 | static int die_compare_name(Dwarf_Die die, const char *tname) | |
155 | { | |
156 | char *name; | |
157 | int ret; | |
158 | ret = dwarf_diename(die, &name, &__dw_error); | |
159 | ERR_IF(ret == DW_DLV_ERROR); | |
160 | if (ret == DW_DLV_OK) { | |
161 | ret = strcmp(tname, name); | |
162 | dwarf_dealloc(__dw_debug, name, DW_DLA_STRING); | |
163 | } else | |
164 | ret = -1; | |
165 | return ret; | |
166 | } | |
167 | ||
168 | /* Check the address is in the subprogram(function). */ | |
169 | static int die_within_subprogram(Dwarf_Die sp_die, Dwarf_Addr addr, | |
170 | Dwarf_Signed *offs) | |
171 | { | |
172 | Dwarf_Addr lopc, hipc; | |
173 | int ret; | |
174 | ||
175 | /* TODO: check ranges */ | |
176 | ret = dwarf_lowpc(sp_die, &lopc, &__dw_error); | |
177 | ERR_IF(ret == DW_DLV_ERROR); | |
178 | if (ret == DW_DLV_NO_ENTRY) | |
179 | return 0; | |
180 | ret = dwarf_highpc(sp_die, &hipc, &__dw_error); | |
181 | ERR_IF(ret != DW_DLV_OK); | |
182 | if (lopc <= addr && addr < hipc) { | |
183 | *offs = addr - lopc; | |
184 | return 1; | |
185 | } else | |
186 | return 0; | |
187 | } | |
188 | ||
189 | /* Check the die is inlined function */ | |
190 | static Dwarf_Bool die_inlined_subprogram(Dwarf_Die die) | |
191 | { | |
192 | /* TODO: check strictly */ | |
193 | Dwarf_Bool inl; | |
194 | int ret; | |
195 | ||
196 | ret = dwarf_hasattr(die, DW_AT_inline, &inl, &__dw_error); | |
197 | ERR_IF(ret == DW_DLV_ERROR); | |
198 | return inl; | |
199 | } | |
200 | ||
201 | /* Get the offset of abstruct_origin */ | |
202 | static Dwarf_Off die_get_abstract_origin(Dwarf_Die die) | |
203 | { | |
204 | Dwarf_Attribute attr; | |
205 | Dwarf_Off cu_offs; | |
206 | int ret; | |
207 | ||
208 | ret = dwarf_attr(die, DW_AT_abstract_origin, &attr, &__dw_error); | |
209 | ERR_IF(ret != DW_DLV_OK); | |
210 | ret = dwarf_formref(attr, &cu_offs, &__dw_error); | |
211 | ERR_IF(ret != DW_DLV_OK); | |
212 | dwarf_dealloc(__dw_debug, attr, DW_DLA_ATTR); | |
213 | return cu_offs; | |
214 | } | |
215 | ||
216 | /* Get entry pc(or low pc, 1st entry of ranges) of the die */ | |
217 | static Dwarf_Addr die_get_entrypc(Dwarf_Die die) | |
218 | { | |
219 | Dwarf_Attribute attr; | |
220 | Dwarf_Addr addr; | |
221 | Dwarf_Off offs; | |
222 | Dwarf_Ranges *ranges; | |
223 | Dwarf_Signed cnt; | |
224 | int ret; | |
225 | ||
226 | /* Try to get entry pc */ | |
227 | ret = dwarf_attr(die, DW_AT_entry_pc, &attr, &__dw_error); | |
228 | ERR_IF(ret == DW_DLV_ERROR); | |
229 | if (ret == DW_DLV_OK) { | |
230 | ret = dwarf_formaddr(attr, &addr, &__dw_error); | |
231 | ERR_IF(ret != DW_DLV_OK); | |
232 | dwarf_dealloc(__dw_debug, attr, DW_DLA_ATTR); | |
233 | return addr; | |
234 | } | |
235 | ||
236 | /* Try to get low pc */ | |
237 | ret = dwarf_lowpc(die, &addr, &__dw_error); | |
238 | ERR_IF(ret == DW_DLV_ERROR); | |
239 | if (ret == DW_DLV_OK) | |
240 | return addr; | |
241 | ||
242 | /* Try to get ranges */ | |
243 | ret = dwarf_attr(die, DW_AT_ranges, &attr, &__dw_error); | |
244 | ERR_IF(ret != DW_DLV_OK); | |
245 | ret = dwarf_formref(attr, &offs, &__dw_error); | |
246 | ERR_IF(ret != DW_DLV_OK); | |
247 | ret = dwarf_get_ranges(__dw_debug, offs, &ranges, &cnt, NULL, | |
248 | &__dw_error); | |
249 | ERR_IF(ret != DW_DLV_OK); | |
250 | addr = ranges[0].dwr_addr1; | |
251 | dwarf_ranges_dealloc(__dw_debug, ranges, cnt); | |
252 | return addr; | |
253 | } | |
254 | ||
255 | /* | |
256 | * Search a Die from Die tree. | |
257 | * Note: cur_link->die should be deallocated in this function. | |
258 | */ | |
259 | static int __search_die_tree(struct die_link *cur_link, | |
260 | int (*die_cb)(struct die_link *, void *), | |
261 | void *data) | |
262 | { | |
263 | Dwarf_Die new_die; | |
264 | struct die_link new_link; | |
265 | int ret; | |
266 | ||
267 | if (!die_cb) | |
268 | return 0; | |
269 | ||
270 | /* Check current die */ | |
271 | while (!(ret = die_cb(cur_link, data))) { | |
272 | /* Check child die */ | |
273 | ret = dwarf_child(cur_link->die, &new_die, &__dw_error); | |
274 | ERR_IF(ret == DW_DLV_ERROR); | |
275 | if (ret == DW_DLV_OK) { | |
276 | new_link.parent = cur_link; | |
277 | new_link.die = new_die; | |
278 | ret = __search_die_tree(&new_link, die_cb, data); | |
279 | if (ret) | |
280 | break; | |
281 | } | |
282 | ||
283 | /* Move to next sibling */ | |
284 | ret = dwarf_siblingof(__dw_debug, cur_link->die, &new_die, | |
285 | &__dw_error); | |
286 | ERR_IF(ret == DW_DLV_ERROR); | |
287 | dwarf_dealloc(__dw_debug, cur_link->die, DW_DLA_DIE); | |
288 | cur_link->die = new_die; | |
289 | if (ret == DW_DLV_NO_ENTRY) | |
290 | return 0; | |
291 | } | |
292 | dwarf_dealloc(__dw_debug, cur_link->die, DW_DLA_DIE); | |
293 | return ret; | |
294 | } | |
295 | ||
296 | /* Search a die in its children's die tree */ | |
297 | static int search_die_from_children(Dwarf_Die parent_die, | |
298 | int (*die_cb)(struct die_link *, void *), | |
299 | void *data) | |
300 | { | |
301 | struct die_link new_link; | |
302 | int ret; | |
303 | ||
304 | new_link.parent = NULL; | |
305 | ret = dwarf_child(parent_die, &new_link.die, &__dw_error); | |
306 | ERR_IF(ret == DW_DLV_ERROR); | |
307 | if (ret == DW_DLV_OK) | |
308 | return __search_die_tree(&new_link, die_cb, data); | |
309 | else | |
310 | return 0; | |
311 | } | |
312 | ||
313 | /* Find a locdesc corresponding to the address */ | |
314 | static int attr_get_locdesc(Dwarf_Attribute attr, Dwarf_Locdesc *desc, | |
315 | Dwarf_Addr addr) | |
316 | { | |
317 | Dwarf_Signed lcnt; | |
318 | Dwarf_Locdesc **llbuf; | |
319 | int ret, i; | |
320 | ||
321 | ret = dwarf_loclist_n(attr, &llbuf, &lcnt, &__dw_error); | |
322 | ERR_IF(ret != DW_DLV_OK); | |
323 | ret = DW_DLV_NO_ENTRY; | |
324 | for (i = 0; i < lcnt; ++i) { | |
325 | if (llbuf[i]->ld_lopc <= addr && | |
326 | llbuf[i]->ld_hipc > addr) { | |
327 | memcpy(desc, llbuf[i], sizeof(Dwarf_Locdesc)); | |
328 | desc->ld_s = | |
329 | malloc(sizeof(Dwarf_Loc) * llbuf[i]->ld_cents); | |
330 | ERR_IF(desc->ld_s == NULL); | |
331 | memcpy(desc->ld_s, llbuf[i]->ld_s, | |
332 | sizeof(Dwarf_Loc) * llbuf[i]->ld_cents); | |
333 | ret = DW_DLV_OK; | |
334 | break; | |
335 | } | |
336 | dwarf_dealloc(__dw_debug, llbuf[i]->ld_s, DW_DLA_LOC_BLOCK); | |
337 | dwarf_dealloc(__dw_debug, llbuf[i], DW_DLA_LOCDESC); | |
338 | } | |
339 | /* Releasing loop */ | |
340 | for (; i < lcnt; ++i) { | |
341 | dwarf_dealloc(__dw_debug, llbuf[i]->ld_s, DW_DLA_LOC_BLOCK); | |
342 | dwarf_dealloc(__dw_debug, llbuf[i], DW_DLA_LOCDESC); | |
343 | } | |
344 | dwarf_dealloc(__dw_debug, llbuf, DW_DLA_LIST); | |
345 | return ret; | |
346 | } | |
347 | ||
348 | /* | |
349 | * Probe finder related functions | |
350 | */ | |
351 | ||
352 | /* Show a location */ | |
353 | static void show_location(Dwarf_Loc *loc, struct probe_finder *pf) | |
354 | { | |
355 | Dwarf_Small op; | |
356 | Dwarf_Unsigned regn; | |
357 | Dwarf_Signed offs; | |
358 | int deref = 0, ret; | |
359 | const char *regs; | |
360 | ||
361 | op = loc->lr_atom; | |
362 | ||
363 | /* If this is based on frame buffer, set the offset */ | |
364 | if (op == DW_OP_fbreg) { | |
365 | deref = 1; | |
366 | offs = (Dwarf_Signed)loc->lr_number; | |
367 | op = pf->fbloc.ld_s[0].lr_atom; | |
368 | loc = &pf->fbloc.ld_s[0]; | |
369 | } else | |
370 | offs = 0; | |
371 | ||
372 | if (op >= DW_OP_breg0 && op <= DW_OP_breg31) { | |
373 | regn = op - DW_OP_breg0; | |
374 | offs += (Dwarf_Signed)loc->lr_number; | |
375 | deref = 1; | |
376 | } else if (op >= DW_OP_reg0 && op <= DW_OP_reg31) { | |
377 | regn = op - DW_OP_reg0; | |
378 | } else if (op == DW_OP_bregx) { | |
379 | regn = loc->lr_number; | |
380 | offs += (Dwarf_Signed)loc->lr_number2; | |
381 | deref = 1; | |
382 | } else if (op == DW_OP_regx) { | |
383 | regn = loc->lr_number; | |
384 | } else | |
385 | msg_exit(-EINVAL, "Dwarf_OP %d is not supported.\n", op); | |
386 | ||
387 | regs = get_arch_regstr(regn); | |
388 | if (!regs) | |
389 | msg_exit(-EINVAL, "%lld exceeds max register number.\n", regn); | |
390 | ||
391 | if (deref) | |
392 | ret = snprintf(pf->buf, pf->len, | |
393 | " %s=%+lld(%s)", pf->var, offs, regs); | |
394 | else | |
395 | ret = snprintf(pf->buf, pf->len, " %s=%s", pf->var, regs); | |
396 | ERR_IF(ret < 0); | |
397 | ERR_IF(ret >= pf->len); | |
398 | } | |
399 | ||
400 | /* Show a variables in kprobe event format */ | |
401 | static void show_variable(Dwarf_Die vr_die, struct probe_finder *pf) | |
402 | { | |
403 | Dwarf_Attribute attr; | |
404 | Dwarf_Locdesc ld; | |
405 | int ret; | |
406 | ||
407 | ret = dwarf_attr(vr_die, DW_AT_location, &attr, &__dw_error); | |
408 | if (ret != DW_DLV_OK) | |
409 | goto error; | |
410 | ret = attr_get_locdesc(attr, &ld, (pf->addr - pf->cu_base)); | |
411 | if (ret != DW_DLV_OK) | |
412 | goto error; | |
413 | /* TODO? */ | |
414 | ERR_IF(ld.ld_cents != 1); | |
415 | show_location(&ld.ld_s[0], pf); | |
416 | free(ld.ld_s); | |
417 | dwarf_dealloc(__dw_debug, attr, DW_DLA_ATTR); | |
418 | return ; | |
419 | error: | |
420 | msg_exit(-1, "Failed to find the location of %s at this address.\n" | |
421 | " Perhaps, it was optimized out.\n", pf->var); | |
422 | } | |
423 | ||
424 | static int variable_callback(struct die_link *dlink, void *data) | |
425 | { | |
426 | struct probe_finder *pf = (struct probe_finder *)data; | |
427 | Dwarf_Half tag; | |
428 | int ret; | |
429 | ||
430 | ret = dwarf_tag(dlink->die, &tag, &__dw_error); | |
431 | ERR_IF(ret == DW_DLV_ERROR); | |
432 | if ((tag == DW_TAG_formal_parameter || | |
433 | tag == DW_TAG_variable) && | |
434 | (die_compare_name(dlink->die, pf->var) == 0)) { | |
435 | show_variable(dlink->die, pf); | |
436 | return 1; | |
437 | } | |
438 | /* TODO: Support struct members and arrays */ | |
439 | return 0; | |
440 | } | |
441 | ||
442 | /* Find a variable in a subprogram die */ | |
443 | static void find_variable(Dwarf_Die sp_die, struct probe_finder *pf) | |
444 | { | |
445 | int ret; | |
446 | ||
447 | if (!is_c_varname(pf->var)) { | |
448 | /* Output raw parameters */ | |
449 | ret = snprintf(pf->buf, pf->len, " %s", pf->var); | |
450 | ERR_IF(ret < 0); | |
451 | ERR_IF(ret >= pf->len); | |
452 | return ; | |
453 | } | |
454 | ||
455 | debug("Searching '%s' variable in context.\n", pf->var); | |
456 | /* Search child die for local variables and parameters. */ | |
457 | ret = search_die_from_children(sp_die, variable_callback, pf); | |
458 | if (!ret) | |
459 | msg_exit(-1, "Failed to find '%s' in this function.\n", | |
460 | pf->var); | |
461 | } | |
462 | ||
463 | /* Get a frame base on the address */ | |
464 | static void get_current_frame_base(Dwarf_Die sp_die, struct probe_finder *pf) | |
465 | { | |
466 | Dwarf_Attribute attr; | |
467 | int ret; | |
468 | ||
469 | ret = dwarf_attr(sp_die, DW_AT_frame_base, &attr, &__dw_error); | |
470 | ERR_IF(ret != DW_DLV_OK); | |
471 | ret = attr_get_locdesc(attr, &pf->fbloc, (pf->addr - pf->cu_base)); | |
472 | ERR_IF(ret != DW_DLV_OK); | |
473 | dwarf_dealloc(__dw_debug, attr, DW_DLA_ATTR); | |
474 | } | |
475 | ||
476 | static void free_current_frame_base(struct probe_finder *pf) | |
477 | { | |
478 | free(pf->fbloc.ld_s); | |
479 | memset(&pf->fbloc, 0, sizeof(Dwarf_Locdesc)); | |
480 | } | |
481 | ||
482 | /* Show a probe point to output buffer */ | |
483 | static void show_probepoint(Dwarf_Die sp_die, Dwarf_Signed offs, | |
484 | struct probe_finder *pf) | |
485 | { | |
486 | struct probe_point *pp = pf->pp; | |
487 | char *name; | |
488 | char tmp[MAX_PROBE_BUFFER]; | |
489 | int ret, i, len; | |
490 | ||
491 | /* Output name of probe point */ | |
492 | ret = dwarf_diename(sp_die, &name, &__dw_error); | |
493 | ERR_IF(ret == DW_DLV_ERROR); | |
494 | if (ret == DW_DLV_OK) { | |
495 | ret = snprintf(tmp, MAX_PROBE_BUFFER, "%s+%u", name, | |
496 | (unsigned int)offs); | |
497 | dwarf_dealloc(__dw_debug, name, DW_DLA_STRING); | |
498 | } else { | |
499 | /* This function has no name. */ | |
500 | ret = snprintf(tmp, MAX_PROBE_BUFFER, "0x%llx", pf->addr); | |
501 | } | |
502 | ERR_IF(ret < 0); | |
503 | ERR_IF(ret >= MAX_PROBE_BUFFER); | |
504 | len = ret; | |
505 | ||
506 | /* Find each argument */ | |
507 | get_current_frame_base(sp_die, pf); | |
508 | for (i = 0; i < pp->nr_args; i++) { | |
509 | pf->var = pp->args[i]; | |
510 | pf->buf = &tmp[len]; | |
511 | pf->len = MAX_PROBE_BUFFER - len; | |
512 | find_variable(sp_die, pf); | |
513 | len += strlen(pf->buf); | |
514 | } | |
515 | free_current_frame_base(pf); | |
516 | ||
517 | pp->probes[pp->found] = strdup(tmp); | |
518 | pp->found++; | |
519 | } | |
520 | ||
521 | static int probeaddr_callback(struct die_link *dlink, void *data) | |
522 | { | |
523 | struct probe_finder *pf = (struct probe_finder *)data; | |
524 | Dwarf_Half tag; | |
525 | Dwarf_Signed offs; | |
526 | int ret; | |
527 | ||
528 | ret = dwarf_tag(dlink->die, &tag, &__dw_error); | |
529 | ERR_IF(ret == DW_DLV_ERROR); | |
530 | /* Check the address is in this subprogram */ | |
531 | if (tag == DW_TAG_subprogram && | |
532 | die_within_subprogram(dlink->die, pf->addr, &offs)) { | |
533 | show_probepoint(dlink->die, offs, pf); | |
534 | return 1; | |
535 | } | |
536 | return 0; | |
537 | } | |
538 | ||
539 | /* Find probe point from its line number */ | |
540 | static void find_by_line(Dwarf_Die cu_die, struct probe_finder *pf) | |
541 | { | |
542 | struct probe_point *pp = pf->pp; | |
543 | Dwarf_Signed cnt, i; | |
544 | Dwarf_Line *lines; | |
545 | Dwarf_Unsigned lineno = 0; | |
546 | Dwarf_Addr addr; | |
547 | Dwarf_Unsigned fno; | |
548 | int ret; | |
549 | ||
550 | ret = dwarf_srclines(cu_die, &lines, &cnt, &__dw_error); | |
551 | ERR_IF(ret != DW_DLV_OK); | |
552 | ||
553 | for (i = 0; i < cnt; i++) { | |
554 | ret = dwarf_line_srcfileno(lines[i], &fno, &__dw_error); | |
555 | ERR_IF(ret != DW_DLV_OK); | |
556 | if (fno != pf->fno) | |
557 | continue; | |
558 | ||
559 | ret = dwarf_lineno(lines[i], &lineno, &__dw_error); | |
560 | ERR_IF(ret != DW_DLV_OK); | |
561 | if (lineno != (Dwarf_Unsigned)pp->line) | |
562 | continue; | |
563 | ||
564 | ret = dwarf_lineaddr(lines[i], &addr, &__dw_error); | |
565 | ERR_IF(ret != DW_DLV_OK); | |
566 | debug("Probe point found: 0x%llx\n", addr); | |
567 | pf->addr = addr; | |
568 | /* Search a real subprogram including this line, */ | |
569 | ret = search_die_from_children(cu_die, probeaddr_callback, pf); | |
570 | if (ret == 0) | |
571 | msg_exit(-1, | |
572 | "Probe point is not found in subprograms.\n"); | |
573 | /* Continuing, because target line might be inlined. */ | |
574 | } | |
575 | dwarf_srclines_dealloc(__dw_debug, lines, cnt); | |
576 | } | |
577 | ||
578 | /* Search function from function name */ | |
579 | static int probefunc_callback(struct die_link *dlink, void *data) | |
580 | { | |
581 | struct probe_finder *pf = (struct probe_finder *)data; | |
582 | struct probe_point *pp = pf->pp; | |
583 | struct die_link *lk; | |
584 | Dwarf_Signed offs; | |
585 | Dwarf_Half tag; | |
586 | int ret; | |
587 | ||
588 | ret = dwarf_tag(dlink->die, &tag, &__dw_error); | |
589 | ERR_IF(ret == DW_DLV_ERROR); | |
590 | if (tag == DW_TAG_subprogram) { | |
591 | if (die_compare_name(dlink->die, pp->function) == 0) { | |
592 | if (die_inlined_subprogram(dlink->die)) { | |
593 | /* Inlined function, save it. */ | |
594 | ret = dwarf_die_CU_offset(dlink->die, | |
595 | &pf->inl_offs, | |
596 | &__dw_error); | |
597 | ERR_IF(ret != DW_DLV_OK); | |
598 | debug("inline definition offset %lld\n", | |
599 | pf->inl_offs); | |
600 | return 0; | |
601 | } | |
602 | /* Get probe address */ | |
603 | pf->addr = die_get_entrypc(dlink->die); | |
604 | pf->addr += pp->offset; | |
605 | /* TODO: Check the address in this function */ | |
606 | show_probepoint(dlink->die, pp->offset, pf); | |
607 | /* Continue to search */ | |
608 | } | |
609 | } else if (tag == DW_TAG_inlined_subroutine && pf->inl_offs) { | |
610 | if (die_get_abstract_origin(dlink->die) == pf->inl_offs) { | |
611 | /* Get probe address */ | |
612 | pf->addr = die_get_entrypc(dlink->die); | |
613 | pf->addr += pp->offset; | |
614 | debug("found inline addr: 0x%llx\n", pf->addr); | |
615 | /* Inlined function. Get a real subprogram */ | |
616 | for (lk = dlink->parent; lk != NULL; lk = lk->parent) { | |
617 | tag = 0; | |
618 | dwarf_tag(lk->die, &tag, &__dw_error); | |
619 | ERR_IF(ret == DW_DLV_ERROR); | |
620 | if (tag == DW_TAG_subprogram && | |
621 | !die_inlined_subprogram(lk->die)) | |
622 | goto found; | |
623 | } | |
624 | msg_exit(-1, "Failed to find real subprogram.\n"); | |
625 | found: | |
626 | /* Get offset from subprogram */ | |
627 | ret = die_within_subprogram(lk->die, pf->addr, &offs); | |
628 | ERR_IF(!ret); | |
629 | show_probepoint(lk->die, offs, pf); | |
630 | /* Continue to search */ | |
631 | } | |
632 | } | |
633 | return 0; | |
634 | } | |
635 | ||
636 | static void find_by_func(Dwarf_Die cu_die, struct probe_finder *pf) | |
637 | { | |
638 | search_die_from_children(cu_die, probefunc_callback, pf); | |
639 | } | |
640 | ||
641 | /* Find a probe point */ | |
642 | int find_probepoint(int fd, struct probe_point *pp) | |
643 | { | |
644 | Dwarf_Half addr_size = 0; | |
645 | Dwarf_Unsigned next_cuh = 0; | |
646 | Dwarf_Die cu_die = 0; | |
647 | int cu_number = 0, ret; | |
648 | struct probe_finder pf = {.pp = pp}; | |
649 | ||
650 | ret = dwarf_init(fd, DW_DLC_READ, 0, 0, &__dw_debug, &__dw_error); | |
651 | if (ret != DW_DLV_OK) | |
652 | msg_exit(-1, "Failed to call dwarf_init(). " | |
653 | "Maybe, not a dwarf file?\n"); | |
654 | ||
655 | pp->found = 0; | |
656 | while (++cu_number) { | |
657 | /* Search CU (Compilation Unit) */ | |
658 | ret = dwarf_next_cu_header(__dw_debug, NULL, NULL, NULL, | |
659 | &addr_size, &next_cuh, &__dw_error); | |
660 | ERR_IF(ret == DW_DLV_ERROR); | |
661 | if (ret == DW_DLV_NO_ENTRY) | |
662 | break; | |
663 | ||
664 | /* Get the DIE(Debugging Information Entry) of this CU */ | |
665 | ret = dwarf_siblingof(__dw_debug, 0, &cu_die, &__dw_error); | |
666 | ERR_IF(ret != DW_DLV_OK); | |
667 | ||
668 | /* Check if target file is included. */ | |
669 | if (pp->file) | |
670 | pf.fno = die_get_fileno(cu_die, pp->file); | |
671 | ||
672 | if (!pp->file || pf.fno) { | |
673 | /* Save CU base address (for frame_base) */ | |
674 | ret = dwarf_lowpc(cu_die, &pf.cu_base, &__dw_error); | |
675 | ERR_IF(ret == DW_DLV_ERROR); | |
676 | if (ret == DW_DLV_NO_ENTRY) | |
677 | pf.cu_base = 0; | |
678 | if (pp->line) | |
679 | find_by_line(cu_die, &pf); | |
680 | if (pp->function) | |
681 | find_by_func(cu_die, &pf); | |
682 | } | |
683 | dwarf_dealloc(__dw_debug, cu_die, DW_DLA_DIE); | |
684 | } | |
685 | ret = dwarf_finish(__dw_debug, &__dw_error); | |
686 | ERR_IF(ret != DW_DLV_OK); | |
687 | ||
688 | return pp->found; | |
689 | } | |
690 |