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Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty...
[linux/fpc-iii.git] / tools / perf / util / probe-finder.c
blobb5247d777f0e9348d1b77e3f33813c5b7713bce4
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 <stdlib.h>
30 #include <string.h>
31 #include <stdarg.h>
32 #include <dwarf-regs.h>
33
34 #include <linux/bitops.h>
35 #include "event.h"
36 #include "dso.h"
37 #include "debug.h"
38 #include "intlist.h"
39 #include "util.h"
40 #include "symbol.h"
41 #include "probe-finder.h"
42
43 /* Kprobe tracer basic type is up to u64 */
44 #define MAX_BASIC_TYPE_BITS 64
45
46 /* Dwarf FL wrappers */
47 static char *debuginfo_path; /* Currently dummy */
48
49 static const Dwfl_Callbacks offline_callbacks = {
50 .find_debuginfo = dwfl_standard_find_debuginfo,
51 .debuginfo_path = &debuginfo_path,
52
53 .section_address = dwfl_offline_section_address,
54
55 /* We use this table for core files too. */
56 .find_elf = dwfl_build_id_find_elf,
57 };
58
59 /* Get a Dwarf from offline image */
60 static int debuginfo__init_offline_dwarf(struct debuginfo *dbg,
61 const char *path)
62 {
63 int fd;
64
65 fd = open(path, O_RDONLY);
66 if (fd < 0)
67 return fd;
68
69 dbg->dwfl = dwfl_begin(&offline_callbacks);
70 if (!dbg->dwfl)
71 goto error;
72
73 dbg->mod = dwfl_report_offline(dbg->dwfl, "", "", fd);
74 if (!dbg->mod)
75 goto error;
76
77 dbg->dbg = dwfl_module_getdwarf(dbg->mod, &dbg->bias);
78 if (!dbg->dbg)
79 goto error;
80
81 return 0;
82 error:
83 if (dbg->dwfl)
84 dwfl_end(dbg->dwfl);
85 else
86 close(fd);
87 memset(dbg, 0, sizeof(*dbg));
88
89 return -ENOENT;
90 }
91
92 static struct debuginfo *__debuginfo__new(const char *path)
93 {
94 struct debuginfo *dbg = zalloc(sizeof(*dbg));
95 if (!dbg)
96 return NULL;
97
98 if (debuginfo__init_offline_dwarf(dbg, path) < 0)
99 zfree(&dbg);
100 if (dbg)
101 pr_debug("Open Debuginfo file: %s\n", path);
102 return dbg;
103 }
104
105 enum dso_binary_type distro_dwarf_types[] = {
106 DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
107 DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
108 DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
109 DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
110 DSO_BINARY_TYPE__NOT_FOUND,
111 };
112
113 struct debuginfo *debuginfo__new(const char *path)
114 {
115 enum dso_binary_type *type;
116 char buf[PATH_MAX], nil = '\0';
117 struct dso *dso;
118 struct debuginfo *dinfo = NULL;
119
120 /* Try to open distro debuginfo files */
121 dso = dso__new(path);
122 if (!dso)
123 goto out;
124
125 for (type = distro_dwarf_types;
126 !dinfo && *type != DSO_BINARY_TYPE__NOT_FOUND;
127 type++) {
128 if (dso__read_binary_type_filename(dso, *type, &nil,
129 buf, PATH_MAX) < 0)
130 continue;
131 dinfo = __debuginfo__new(buf);
132 }
133 dso__delete(dso);
134
135 out:
136 /* if failed to open all distro debuginfo, open given binary */
137 return dinfo ? : __debuginfo__new(path);
138 }
139
140 void debuginfo__delete(struct debuginfo *dbg)
141 {
142 if (dbg) {
143 if (dbg->dwfl)
144 dwfl_end(dbg->dwfl);
145 free(dbg);
146 }
147 }
148
149 /*
150 * Probe finder related functions
151 */
152
153 static struct probe_trace_arg_ref *alloc_trace_arg_ref(long offs)
154 {
155 struct probe_trace_arg_ref *ref;
156 ref = zalloc(sizeof(struct probe_trace_arg_ref));
157 if (ref != NULL)
158 ref->offset = offs;
159 return ref;
160 }
161
162 /*
163 * Convert a location into trace_arg.
164 * If tvar == NULL, this just checks variable can be converted.
165 * If fentry == true and vr_die is a parameter, do huristic search
166 * for the location fuzzed by function entry mcount.
167 */
168 static int convert_variable_location(Dwarf_Die *vr_die, Dwarf_Addr addr,
169 Dwarf_Op *fb_ops, Dwarf_Die *sp_die,
170 struct probe_trace_arg *tvar)
171 {
172 Dwarf_Attribute attr;
173 Dwarf_Addr tmp = 0;
174 Dwarf_Op *op;
175 size_t nops;
176 unsigned int regn;
177 Dwarf_Word offs = 0;
178 bool ref = false;
179 const char *regs;
180 int ret;
181
182 if (dwarf_attr(vr_die, DW_AT_external, &attr) != NULL)
183 goto static_var;
184
185 /* TODO: handle more than 1 exprs */
186 if (dwarf_attr(vr_die, DW_AT_location, &attr) == NULL)
187 return -EINVAL; /* Broken DIE ? */
188 if (dwarf_getlocation_addr(&attr, addr, &op, &nops, 1) <= 0) {
189 ret = dwarf_entrypc(sp_die, &tmp);
190 if (ret || addr != tmp ||
191 dwarf_tag(vr_die) != DW_TAG_formal_parameter ||
192 dwarf_highpc(sp_die, &tmp))
193 return -ENOENT;
194 /*
195 * This is fuzzed by fentry mcount. We try to find the
196 * parameter location at the earliest address.
197 */
198 for (addr += 1; addr <= tmp; addr++) {
199 if (dwarf_getlocation_addr(&attr, addr, &op,
200 &nops, 1) > 0)
201 goto found;
202 }
203 return -ENOENT;
204 }
205 found:
206 if (nops == 0)
207 /* TODO: Support const_value */
208 return -ENOENT;
209
210 if (op->atom == DW_OP_addr) {
211 static_var:
212 if (!tvar)
213 return 0;
214 /* Static variables on memory (not stack), make @varname */
215 ret = strlen(dwarf_diename(vr_die));
216 tvar->value = zalloc(ret + 2);
217 if (tvar->value == NULL)
218 return -ENOMEM;
219 snprintf(tvar->value, ret + 2, "@%s", dwarf_diename(vr_die));
220 tvar->ref = alloc_trace_arg_ref((long)offs);
221 if (tvar->ref == NULL)
222 return -ENOMEM;
223 return 0;
224 }
225
226 /* If this is based on frame buffer, set the offset */
227 if (op->atom == DW_OP_fbreg) {
228 if (fb_ops == NULL)
229 return -ENOTSUP;
230 ref = true;
231 offs = op->number;
232 op = &fb_ops[0];
233 }
234
235 if (op->atom >= DW_OP_breg0 && op->atom <= DW_OP_breg31) {
236 regn = op->atom - DW_OP_breg0;
237 offs += op->number;
238 ref = true;
239 } else if (op->atom >= DW_OP_reg0 && op->atom <= DW_OP_reg31) {
240 regn = op->atom - DW_OP_reg0;
241 } else if (op->atom == DW_OP_bregx) {
242 regn = op->number;
243 offs += op->number2;
244 ref = true;
245 } else if (op->atom == DW_OP_regx) {
246 regn = op->number;
247 } else {
248 pr_debug("DW_OP %x is not supported.\n", op->atom);
249 return -ENOTSUP;
250 }
251
252 if (!tvar)
253 return 0;
254
255 regs = get_arch_regstr(regn);
256 if (!regs) {
257 /* This should be a bug in DWARF or this tool */
258 pr_warning("Mapping for the register number %u "
259 "missing on this architecture.\n", regn);
260 return -ERANGE;
261 }
262
263 tvar->value = strdup(regs);
264 if (tvar->value == NULL)
265 return -ENOMEM;
266
267 if (ref) {
268 tvar->ref = alloc_trace_arg_ref((long)offs);
269 if (tvar->ref == NULL)
270 return -ENOMEM;
271 }
272 return 0;
273 }
274
275 #define BYTES_TO_BITS(nb) ((nb) * BITS_PER_LONG / sizeof(long))
276
277 static int convert_variable_type(Dwarf_Die *vr_die,
278 struct probe_trace_arg *tvar,
279 const char *cast)
280 {
281 struct probe_trace_arg_ref **ref_ptr = &tvar->ref;
282 Dwarf_Die type;
283 char buf[16];
284 char sbuf[STRERR_BUFSIZE];
285 int bsize, boffs, total;
286 int ret;
287
288 /* TODO: check all types */
289 if (cast && strcmp(cast, "string") != 0) {
290 /* Non string type is OK */
291 tvar->type = strdup(cast);
292 return (tvar->type == NULL) ? -ENOMEM : 0;
293 }
294
295 bsize = dwarf_bitsize(vr_die);
296 if (bsize > 0) {
297 /* This is a bitfield */
298 boffs = dwarf_bitoffset(vr_die);
299 total = dwarf_bytesize(vr_die);
300 if (boffs < 0 || total < 0)
301 return -ENOENT;
302 ret = snprintf(buf, 16, "b%d@%d/%zd", bsize, boffs,
303 BYTES_TO_BITS(total));
304 goto formatted;
305 }
306
307 if (die_get_real_type(vr_die, &type) == NULL) {
308 pr_warning("Failed to get a type information of %s.\n",
309 dwarf_diename(vr_die));
310 return -ENOENT;
311 }
312
313 pr_debug("%s type is %s.\n",
314 dwarf_diename(vr_die), dwarf_diename(&type));
315
316 if (cast && strcmp(cast, "string") == 0) { /* String type */
317 ret = dwarf_tag(&type);
318 if (ret != DW_TAG_pointer_type &&
319 ret != DW_TAG_array_type) {
320 pr_warning("Failed to cast into string: "
321 "%s(%s) is not a pointer nor array.\n",
322 dwarf_diename(vr_die), dwarf_diename(&type));
323 return -EINVAL;
324 }
325 if (die_get_real_type(&type, &type) == NULL) {
326 pr_warning("Failed to get a type"
327 " information.\n");
328 return -ENOENT;
329 }
330 if (ret == DW_TAG_pointer_type) {
331 while (*ref_ptr)
332 ref_ptr = &(*ref_ptr)->next;
333 /* Add new reference with offset +0 */
334 *ref_ptr = zalloc(sizeof(struct probe_trace_arg_ref));
335 if (*ref_ptr == NULL) {
336 pr_warning("Out of memory error\n");
337 return -ENOMEM;
338 }
339 }
340 if (!die_compare_name(&type, "char") &&
341 !die_compare_name(&type, "unsigned char")) {
342 pr_warning("Failed to cast into string: "
343 "%s is not (unsigned) char *.\n",
344 dwarf_diename(vr_die));
345 return -EINVAL;
346 }
347 tvar->type = strdup(cast);
348 return (tvar->type == NULL) ? -ENOMEM : 0;
349 }
350
351 ret = dwarf_bytesize(&type);
352 if (ret <= 0)
353 /* No size ... try to use default type */
354 return 0;
355 ret = BYTES_TO_BITS(ret);
356
357 /* Check the bitwidth */
358 if (ret > MAX_BASIC_TYPE_BITS) {
359 pr_info("%s exceeds max-bitwidth. Cut down to %d bits.\n",
360 dwarf_diename(&type), MAX_BASIC_TYPE_BITS);
361 ret = MAX_BASIC_TYPE_BITS;
362 }
363 ret = snprintf(buf, 16, "%c%d",
364 die_is_signed_type(&type) ? 's' : 'u', ret);
365
366 formatted:
367 if (ret < 0 || ret >= 16) {
368 if (ret >= 16)
369 ret = -E2BIG;
370 pr_warning("Failed to convert variable type: %s\n",
371 strerror_r(-ret, sbuf, sizeof(sbuf)));
372 return ret;
373 }
374 tvar->type = strdup(buf);
375 if (tvar->type == NULL)
376 return -ENOMEM;
377 return 0;
378 }
379
380 static int convert_variable_fields(Dwarf_Die *vr_die, const char *varname,
381 struct perf_probe_arg_field *field,
382 struct probe_trace_arg_ref **ref_ptr,
383 Dwarf_Die *die_mem)
384 {
385 struct probe_trace_arg_ref *ref = *ref_ptr;
386 Dwarf_Die type;
387 Dwarf_Word offs;
388 int ret, tag;
389
390 pr_debug("converting %s in %s\n", field->name, varname);
391 if (die_get_real_type(vr_die, &type) == NULL) {
392 pr_warning("Failed to get the type of %s.\n", varname);
393 return -ENOENT;
394 }
395 pr_debug2("Var real type: (%x)\n", (unsigned)dwarf_dieoffset(&type));
396 tag = dwarf_tag(&type);
397
398 if (field->name[0] == '[' &&
399 (tag == DW_TAG_array_type || tag == DW_TAG_pointer_type)) {
400 if (field->next)
401 /* Save original type for next field */
402 memcpy(die_mem, &type, sizeof(*die_mem));
403 /* Get the type of this array */
404 if (die_get_real_type(&type, &type) == NULL) {
405 pr_warning("Failed to get the type of %s.\n", varname);
406 return -ENOENT;
407 }
408 pr_debug2("Array real type: (%x)\n",
409 (unsigned)dwarf_dieoffset(&type));
410 if (tag == DW_TAG_pointer_type) {
411 ref = zalloc(sizeof(struct probe_trace_arg_ref));
412 if (ref == NULL)
413 return -ENOMEM;
414 if (*ref_ptr)
415 (*ref_ptr)->next = ref;
416 else
417 *ref_ptr = ref;
418 }
419 ref->offset += dwarf_bytesize(&type) * field->index;
420 if (!field->next)
421 /* Save vr_die for converting types */
422 memcpy(die_mem, vr_die, sizeof(*die_mem));
423 goto next;
424 } else if (tag == DW_TAG_pointer_type) {
425 /* Check the pointer and dereference */
426 if (!field->ref) {
427 pr_err("Semantic error: %s must be referred by '->'\n",
428 field->name);
429 return -EINVAL;
430 }
431 /* Get the type pointed by this pointer */
432 if (die_get_real_type(&type, &type) == NULL) {
433 pr_warning("Failed to get the type of %s.\n", varname);
434 return -ENOENT;
435 }
436 /* Verify it is a data structure */
437 tag = dwarf_tag(&type);
438 if (tag != DW_TAG_structure_type && tag != DW_TAG_union_type) {
439 pr_warning("%s is not a data structure nor an union.\n",
440 varname);
441 return -EINVAL;
442 }
443
444 ref = zalloc(sizeof(struct probe_trace_arg_ref));
445 if (ref == NULL)
446 return -ENOMEM;
447 if (*ref_ptr)
448 (*ref_ptr)->next = ref;
449 else
450 *ref_ptr = ref;
451 } else {
452 /* Verify it is a data structure */
453 if (tag != DW_TAG_structure_type && tag != DW_TAG_union_type) {
454 pr_warning("%s is not a data structure nor an union.\n",
455 varname);
456 return -EINVAL;
457 }
458 if (field->name[0] == '[') {
459 pr_err("Semantic error: %s is not a pointor"
460 " nor array.\n", varname);
461 return -EINVAL;
462 }
463 if (field->ref) {
464 pr_err("Semantic error: %s must be referred by '.'\n",
465 field->name);
466 return -EINVAL;
467 }
468 if (!ref) {
469 pr_warning("Structure on a register is not "
470 "supported yet.\n");
471 return -ENOTSUP;
472 }
473 }
474
475 if (die_find_member(&type, field->name, die_mem) == NULL) {
476 pr_warning("%s(type:%s) has no member %s.\n", varname,
477 dwarf_diename(&type), field->name);
478 return -EINVAL;
479 }
480
481 /* Get the offset of the field */
482 if (tag == DW_TAG_union_type) {
483 offs = 0;
484 } else {
485 ret = die_get_data_member_location(die_mem, &offs);
486 if (ret < 0) {
487 pr_warning("Failed to get the offset of %s.\n",
488 field->name);
489 return ret;
490 }
491 }
492 ref->offset += (long)offs;
493
494 next:
495 /* Converting next field */
496 if (field->next)
497 return convert_variable_fields(die_mem, field->name,
498 field->next, &ref, die_mem);
499 else
500 return 0;
501 }
502
503 /* Show a variables in kprobe event format */
504 static int convert_variable(Dwarf_Die *vr_die, struct probe_finder *pf)
505 {
506 Dwarf_Die die_mem;
507 int ret;
508
509 pr_debug("Converting variable %s into trace event.\n",
510 dwarf_diename(vr_die));
511
512 ret = convert_variable_location(vr_die, pf->addr, pf->fb_ops,
513 &pf->sp_die, pf->tvar);
514 if (ret == -ENOENT || ret == -EINVAL)
515 pr_err("Failed to find the location of %s at this address.\n"
516 " Perhaps, it has been optimized out.\n", pf->pvar->var);
517 else if (ret == -ENOTSUP)
518 pr_err("Sorry, we don't support this variable location yet.\n");
519 else if (ret == 0 && pf->pvar->field) {
520 ret = convert_variable_fields(vr_die, pf->pvar->var,
521 pf->pvar->field, &pf->tvar->ref,
522 &die_mem);
523 vr_die = &die_mem;
524 }
525 if (ret == 0)
526 ret = convert_variable_type(vr_die, pf->tvar, pf->pvar->type);
527 /* *expr will be cached in libdw. Don't free it. */
528 return ret;
529 }
530
531 /* Find a variable in a scope DIE */
532 static int find_variable(Dwarf_Die *sc_die, struct probe_finder *pf)
533 {
534 Dwarf_Die vr_die;
535 char buf[32], *ptr;
536 int ret = 0;
537
538 if (!is_c_varname(pf->pvar->var)) {
539 /* Copy raw parameters */
540 pf->tvar->value = strdup(pf->pvar->var);
541 if (pf->tvar->value == NULL)
542 return -ENOMEM;
543 if (pf->pvar->type) {
544 pf->tvar->type = strdup(pf->pvar->type);
545 if (pf->tvar->type == NULL)
546 return -ENOMEM;
547 }
548 if (pf->pvar->name) {
549 pf->tvar->name = strdup(pf->pvar->name);
550 if (pf->tvar->name == NULL)
551 return -ENOMEM;
552 } else
553 pf->tvar->name = NULL;
554 return 0;
555 }
556
557 if (pf->pvar->name)
558 pf->tvar->name = strdup(pf->pvar->name);
559 else {
560 ret = synthesize_perf_probe_arg(pf->pvar, buf, 32);
561 if (ret < 0)
562 return ret;
563 ptr = strchr(buf, ':'); /* Change type separator to _ */
564 if (ptr)
565 *ptr = '_';
566 pf->tvar->name = strdup(buf);
567 }
568 if (pf->tvar->name == NULL)
569 return -ENOMEM;
570
571 pr_debug("Searching '%s' variable in context.\n", pf->pvar->var);
572 /* Search child die for local variables and parameters. */
573 if (!die_find_variable_at(sc_die, pf->pvar->var, pf->addr, &vr_die)) {
574 /* Search again in global variables */
575 if (!die_find_variable_at(&pf->cu_die, pf->pvar->var, 0, &vr_die))
576 pr_warning("Failed to find '%s' in this function.\n",
577 pf->pvar->var);
578 ret = -ENOENT;
579 }
580 if (ret >= 0)
581 ret = convert_variable(&vr_die, pf);
582
583 return ret;
584 }
585
586 /* Convert subprogram DIE to trace point */
587 static int convert_to_trace_point(Dwarf_Die *sp_die, Dwfl_Module *mod,
588 Dwarf_Addr paddr, bool retprobe,
589 struct probe_trace_point *tp)
590 {
591 Dwarf_Addr eaddr, highaddr;
592 GElf_Sym sym;
593 const char *symbol;
594
595 /* Verify the address is correct */
596 if (dwarf_entrypc(sp_die, &eaddr) != 0) {
597 pr_warning("Failed to get entry address of %s\n",
598 dwarf_diename(sp_die));
599 return -ENOENT;
600 }
601 if (dwarf_highpc(sp_die, &highaddr) != 0) {
602 pr_warning("Failed to get end address of %s\n",
603 dwarf_diename(sp_die));
604 return -ENOENT;
605 }
606 if (paddr > highaddr) {
607 pr_warning("Offset specified is greater than size of %s\n",
608 dwarf_diename(sp_die));
609 return -EINVAL;
610 }
611
612 symbol = dwarf_diename(sp_die);
613 if (!symbol) {
614 /* Try to get the symbol name from symtab */
615 symbol = dwfl_module_addrsym(mod, paddr, &sym, NULL);
616 if (!symbol) {
617 pr_warning("Failed to find symbol at 0x%lx\n",
618 (unsigned long)paddr);
619 return -ENOENT;
620 }
621 eaddr = sym.st_value;
622 }
623 tp->offset = (unsigned long)(paddr - eaddr);
624 tp->address = (unsigned long)paddr;
625 tp->symbol = strdup(symbol);
626 if (!tp->symbol)
627 return -ENOMEM;
628
629 /* Return probe must be on the head of a subprogram */
630 if (retprobe) {
631 if (eaddr != paddr) {
632 pr_warning("Return probe must be on the head of"
633 " a real function.\n");
634 return -EINVAL;
635 }
636 tp->retprobe = true;
637 }
638
639 return 0;
640 }
641
642 /* Call probe_finder callback with scope DIE */
643 static int call_probe_finder(Dwarf_Die *sc_die, struct probe_finder *pf)
644 {
645 Dwarf_Attribute fb_attr;
646 size_t nops;
647 int ret;
648
649 if (!sc_die) {
650 pr_err("Caller must pass a scope DIE. Program error.\n");
651 return -EINVAL;
652 }
653
654 /* If not a real subprogram, find a real one */
655 if (!die_is_func_def(sc_die)) {
656 if (!die_find_realfunc(&pf->cu_die, pf->addr, &pf->sp_die)) {
657 pr_warning("Failed to find probe point in any "
658 "functions.\n");
659 return -ENOENT;
660 }
661 } else
662 memcpy(&pf->sp_die, sc_die, sizeof(Dwarf_Die));
663
664 /* Get the frame base attribute/ops from subprogram */
665 dwarf_attr(&pf->sp_die, DW_AT_frame_base, &fb_attr);
666 ret = dwarf_getlocation_addr(&fb_attr, pf->addr, &pf->fb_ops, &nops, 1);
667 if (ret <= 0 || nops == 0) {
668 pf->fb_ops = NULL;
669 #if _ELFUTILS_PREREQ(0, 142)
670 } else if (nops == 1 && pf->fb_ops[0].atom == DW_OP_call_frame_cfa &&
671 pf->cfi != NULL) {
672 Dwarf_Frame *frame;
673 if (dwarf_cfi_addrframe(pf->cfi, pf->addr, &frame) != 0 ||
674 dwarf_frame_cfa(frame, &pf->fb_ops, &nops) != 0) {
675 pr_warning("Failed to get call frame on 0x%jx\n",
676 (uintmax_t)pf->addr);
677 return -ENOENT;
678 }
679 #endif
680 }
681
682 /* Call finder's callback handler */
683 ret = pf->callback(sc_die, pf);
684
685 /* *pf->fb_ops will be cached in libdw. Don't free it. */
686 pf->fb_ops = NULL;
687
688 return ret;
689 }
690
691 struct find_scope_param {
692 const char *function;
693 const char *file;
694 int line;
695 int diff;
696 Dwarf_Die *die_mem;
697 bool found;
698 };
699
700 static int find_best_scope_cb(Dwarf_Die *fn_die, void *data)
701 {
702 struct find_scope_param *fsp = data;
703 const char *file;
704 int lno;
705
706 /* Skip if declared file name does not match */
707 if (fsp->file) {
708 file = dwarf_decl_file(fn_die);
709 if (!file || strcmp(fsp->file, file) != 0)
710 return 0;
711 }
712 /* If the function name is given, that's what user expects */
713 if (fsp->function) {
714 if (die_compare_name(fn_die, fsp->function)) {
715 memcpy(fsp->die_mem, fn_die, sizeof(Dwarf_Die));
716 fsp->found = true;
717 return 1;
718 }
719 } else {
720 /* With the line number, find the nearest declared DIE */
721 dwarf_decl_line(fn_die, &lno);
722 if (lno < fsp->line && fsp->diff > fsp->line - lno) {
723 /* Keep a candidate and continue */
724 fsp->diff = fsp->line - lno;
725 memcpy(fsp->die_mem, fn_die, sizeof(Dwarf_Die));
726 fsp->found = true;
727 }
728 }
729 return 0;
730 }
731
732 /* Find an appropriate scope fits to given conditions */
733 static Dwarf_Die *find_best_scope(struct probe_finder *pf, Dwarf_Die *die_mem)
734 {
735 struct find_scope_param fsp = {
736 .function = pf->pev->point.function,
737 .file = pf->fname,
738 .line = pf->lno,
739 .diff = INT_MAX,
740 .die_mem = die_mem,
741 .found = false,
742 };
743
744 cu_walk_functions_at(&pf->cu_die, pf->addr, find_best_scope_cb, &fsp);
745
746 return fsp.found ? die_mem : NULL;
747 }
748
749 static int probe_point_line_walker(const char *fname, int lineno,
750 Dwarf_Addr addr, void *data)
751 {
752 struct probe_finder *pf = data;
753 Dwarf_Die *sc_die, die_mem;
754 int ret;
755
756 if (lineno != pf->lno || strtailcmp(fname, pf->fname) != 0)
757 return 0;
758
759 pf->addr = addr;
760 sc_die = find_best_scope(pf, &die_mem);
761 if (!sc_die) {
762 pr_warning("Failed to find scope of probe point.\n");
763 return -ENOENT;
764 }
765
766 ret = call_probe_finder(sc_die, pf);
767
768 /* Continue if no error, because the line will be in inline function */
769 return ret < 0 ? ret : 0;
770 }
771
772 /* Find probe point from its line number */
773 static int find_probe_point_by_line(struct probe_finder *pf)
774 {
775 return die_walk_lines(&pf->cu_die, probe_point_line_walker, pf);
776 }
777
778 /* Find lines which match lazy pattern */
779 static int find_lazy_match_lines(struct intlist *list,
780 const char *fname, const char *pat)
781 {
782 FILE *fp;
783 char *line = NULL;
784 size_t line_len;
785 ssize_t len;
786 int count = 0, linenum = 1;
787 char sbuf[STRERR_BUFSIZE];
788
789 fp = fopen(fname, "r");
790 if (!fp) {
791 pr_warning("Failed to open %s: %s\n", fname,
792 strerror_r(errno, sbuf, sizeof(sbuf)));
793 return -errno;
794 }
795
796 while ((len = getline(&line, &line_len, fp)) > 0) {
797
798 if (line[len - 1] == '\n')
799 line[len - 1] = '\0';
800
801 if (strlazymatch(line, pat)) {
802 intlist__add(list, linenum);
803 count++;
804 }
805 linenum++;
806 }
807
808 if (ferror(fp))
809 count = -errno;
810 free(line);
811 fclose(fp);
812
813 if (count == 0)
814 pr_debug("No matched lines found in %s.\n", fname);
815 return count;
816 }
817
818 static int probe_point_lazy_walker(const char *fname, int lineno,
819 Dwarf_Addr addr, void *data)
820 {
821 struct probe_finder *pf = data;
822 Dwarf_Die *sc_die, die_mem;
823 int ret;
824
825 if (!intlist__has_entry(pf->lcache, lineno) ||
826 strtailcmp(fname, pf->fname) != 0)
827 return 0;
828
829 pr_debug("Probe line found: line:%d addr:0x%llx\n",
830 lineno, (unsigned long long)addr);
831 pf->addr = addr;
832 pf->lno = lineno;
833 sc_die = find_best_scope(pf, &die_mem);
834 if (!sc_die) {
835 pr_warning("Failed to find scope of probe point.\n");
836 return -ENOENT;
837 }
838
839 ret = call_probe_finder(sc_die, pf);
840
841 /*
842 * Continue if no error, because the lazy pattern will match
843 * to other lines
844 */
845 return ret < 0 ? ret : 0;
846 }
847
848 /* Find probe points from lazy pattern */
849 static int find_probe_point_lazy(Dwarf_Die *sp_die, struct probe_finder *pf)
850 {
851 int ret = 0;
852
853 if (intlist__empty(pf->lcache)) {
854 /* Matching lazy line pattern */
855 ret = find_lazy_match_lines(pf->lcache, pf->fname,
856 pf->pev->point.lazy_line);
857 if (ret <= 0)
858 return ret;
859 }
860
861 return die_walk_lines(sp_die, probe_point_lazy_walker, pf);
862 }
863
864 static int probe_point_inline_cb(Dwarf_Die *in_die, void *data)
865 {
866 struct probe_finder *pf = data;
867 struct perf_probe_point *pp = &pf->pev->point;
868 Dwarf_Addr addr;
869 int ret;
870
871 if (pp->lazy_line)
872 ret = find_probe_point_lazy(in_die, pf);
873 else {
874 /* Get probe address */
875 if (dwarf_entrypc(in_die, &addr) != 0) {
876 pr_warning("Failed to get entry address of %s.\n",
877 dwarf_diename(in_die));
878 return -ENOENT;
879 }
880 pf->addr = addr;
881 pf->addr += pp->offset;
882 pr_debug("found inline addr: 0x%jx\n",
883 (uintmax_t)pf->addr);
884
885 ret = call_probe_finder(in_die, pf);
886 }
887
888 return ret;
889 }
890
891 /* Callback parameter with return value for libdw */
892 struct dwarf_callback_param {
893 void *data;
894 int retval;
895 };
896
897 /* Search function from function name */
898 static int probe_point_search_cb(Dwarf_Die *sp_die, void *data)
899 {
900 struct dwarf_callback_param *param = data;
901 struct probe_finder *pf = param->data;
902 struct perf_probe_point *pp = &pf->pev->point;
903
904 /* Check tag and diename */
905 if (!die_is_func_def(sp_die) ||
906 !die_compare_name(sp_die, pp->function))
907 return DWARF_CB_OK;
908
909 /* Check declared file */
910 if (pp->file && strtailcmp(pp->file, dwarf_decl_file(sp_die)))
911 return DWARF_CB_OK;
912
913 pf->fname = dwarf_decl_file(sp_die);
914 if (pp->line) { /* Function relative line */
915 dwarf_decl_line(sp_die, &pf->lno);
916 pf->lno += pp->line;
917 param->retval = find_probe_point_by_line(pf);
918 } else if (!dwarf_func_inline(sp_die)) {
919 /* Real function */
920 if (pp->lazy_line)
921 param->retval = find_probe_point_lazy(sp_die, pf);
922 else {
923 if (dwarf_entrypc(sp_die, &pf->addr) != 0) {
924 pr_warning("Failed to get entry address of "
925 "%s.\n", dwarf_diename(sp_die));
926 param->retval = -ENOENT;
927 return DWARF_CB_ABORT;
928 }
929 pf->addr += pp->offset;
930 /* TODO: Check the address in this function */
931 param->retval = call_probe_finder(sp_die, pf);
932 }
933 } else
934 /* Inlined function: search instances */
935 param->retval = die_walk_instances(sp_die,
936 probe_point_inline_cb, (void *)pf);
937
938 return DWARF_CB_ABORT; /* Exit; no same symbol in this CU. */
939 }
940
941 static int find_probe_point_by_func(struct probe_finder *pf)
942 {
943 struct dwarf_callback_param _param = {.data = (void *)pf,
944 .retval = 0};
945 dwarf_getfuncs(&pf->cu_die, probe_point_search_cb, &_param, 0);
946 return _param.retval;
947 }
948
949 struct pubname_callback_param {
950 char *function;
951 char *file;
952 Dwarf_Die *cu_die;
953 Dwarf_Die *sp_die;
954 int found;
955 };
956
957 static int pubname_search_cb(Dwarf *dbg, Dwarf_Global *gl, void *data)
958 {
959 struct pubname_callback_param *param = data;
960
961 if (dwarf_offdie(dbg, gl->die_offset, param->sp_die)) {
962 if (dwarf_tag(param->sp_die) != DW_TAG_subprogram)
963 return DWARF_CB_OK;
964
965 if (die_compare_name(param->sp_die, param->function)) {
966 if (!dwarf_offdie(dbg, gl->cu_offset, param->cu_die))
967 return DWARF_CB_OK;
968
969 if (param->file &&
970 strtailcmp(param->file, dwarf_decl_file(param->sp_die)))
971 return DWARF_CB_OK;
972
973 param->found = 1;
974 return DWARF_CB_ABORT;
975 }
976 }
977
978 return DWARF_CB_OK;
979 }
980
981 /* Find probe points from debuginfo */
982 static int debuginfo__find_probes(struct debuginfo *dbg,
983 struct probe_finder *pf)
984 {
985 struct perf_probe_point *pp = &pf->pev->point;
986 Dwarf_Off off, noff;
987 size_t cuhl;
988 Dwarf_Die *diep;
989 int ret = 0;
990
991 #if _ELFUTILS_PREREQ(0, 142)
992 Elf *elf;
993 GElf_Ehdr ehdr;
994 GElf_Shdr shdr;
995
996 /* Get the call frame information from this dwarf */
997 elf = dwarf_getelf(dbg->dbg);
998 if (elf == NULL)
999 return -EINVAL;
1000
1001 if (gelf_getehdr(elf, &ehdr) == NULL)
1002 return -EINVAL;
1003
1004 if (elf_section_by_name(elf, &ehdr, &shdr, ".eh_frame", NULL) &&
1005 shdr.sh_type == SHT_PROGBITS) {
1006 pf->cfi = dwarf_getcfi_elf(elf);
1007 } else {
1008 pf->cfi = dwarf_getcfi(dbg->dbg);
1009 }
1010 #endif
1011
1012 off = 0;
1013 pf->lcache = intlist__new(NULL);
1014 if (!pf->lcache)
1015 return -ENOMEM;
1016
1017 /* Fastpath: lookup by function name from .debug_pubnames section */
1018 if (pp->function) {
1019 struct pubname_callback_param pubname_param = {
1020 .function = pp->function,
1021 .file = pp->file,
1022 .cu_die = &pf->cu_die,
1023 .sp_die = &pf->sp_die,
1024 .found = 0,
1025 };
1026 struct dwarf_callback_param probe_param = {
1027 .data = pf,
1028 };
1029
1030 dwarf_getpubnames(dbg->dbg, pubname_search_cb,
1031 &pubname_param, 0);
1032 if (pubname_param.found) {
1033 ret = probe_point_search_cb(&pf->sp_die, &probe_param);
1034 if (ret)
1035 goto found;
1036 }
1037 }
1038
1039 /* Loop on CUs (Compilation Unit) */
1040 while (!dwarf_nextcu(dbg->dbg, off, &noff, &cuhl, NULL, NULL, NULL)) {
1041 /* Get the DIE(Debugging Information Entry) of this CU */
1042 diep = dwarf_offdie(dbg->dbg, off + cuhl, &pf->cu_die);
1043 if (!diep)
1044 continue;
1045
1046 /* Check if target file is included. */
1047 if (pp->file)
1048 pf->fname = cu_find_realpath(&pf->cu_die, pp->file);
1049 else
1050 pf->fname = NULL;
1051
1052 if (!pp->file || pf->fname) {
1053 if (pp->function)
1054 ret = find_probe_point_by_func(pf);
1055 else if (pp->lazy_line)
1056 ret = find_probe_point_lazy(NULL, pf);
1057 else {
1058 pf->lno = pp->line;
1059 ret = find_probe_point_by_line(pf);
1060 }
1061 if (ret < 0)
1062 break;
1063 }
1064 off = noff;
1065 }
1066
1067 found:
1068 intlist__delete(pf->lcache);
1069 pf->lcache = NULL;
1070
1071 return ret;
1072 }
1073
1074 struct local_vars_finder {
1075 struct probe_finder *pf;
1076 struct perf_probe_arg *args;
1077 int max_args;
1078 int nargs;
1079 int ret;
1080 };
1081
1082 /* Collect available variables in this scope */
1083 static int copy_variables_cb(Dwarf_Die *die_mem, void *data)
1084 {
1085 struct local_vars_finder *vf = data;
1086 struct probe_finder *pf = vf->pf;
1087 int tag;
1088
1089 tag = dwarf_tag(die_mem);
1090 if (tag == DW_TAG_formal_parameter ||
1091 tag == DW_TAG_variable) {
1092 if (convert_variable_location(die_mem, vf->pf->addr,
1093 vf->pf->fb_ops, &pf->sp_die,
1094 NULL) == 0) {
1095 vf->args[vf->nargs].var = (char *)dwarf_diename(die_mem);
1096 if (vf->args[vf->nargs].var == NULL) {
1097 vf->ret = -ENOMEM;
1098 return DIE_FIND_CB_END;
1099 }
1100 pr_debug(" %s", vf->args[vf->nargs].var);
1101 vf->nargs++;
1102 }
1103 }
1104
1105 if (dwarf_haspc(die_mem, vf->pf->addr))
1106 return DIE_FIND_CB_CONTINUE;
1107 else
1108 return DIE_FIND_CB_SIBLING;
1109 }
1110
1111 static int expand_probe_args(Dwarf_Die *sc_die, struct probe_finder *pf,
1112 struct perf_probe_arg *args)
1113 {
1114 Dwarf_Die die_mem;
1115 int i;
1116 int n = 0;
1117 struct local_vars_finder vf = {.pf = pf, .args = args,
1118 .max_args = MAX_PROBE_ARGS, .ret = 0};
1119
1120 for (i = 0; i < pf->pev->nargs; i++) {
1121 /* var never be NULL */
1122 if (strcmp(pf->pev->args[i].var, "$vars") == 0) {
1123 pr_debug("Expanding $vars into:");
1124 vf.nargs = n;
1125 /* Special local variables */
1126 die_find_child(sc_die, copy_variables_cb, (void *)&vf,
1127 &die_mem);
1128 pr_debug(" (%d)\n", vf.nargs - n);
1129 if (vf.ret < 0)
1130 return vf.ret;
1131 n = vf.nargs;
1132 } else {
1133 /* Copy normal argument */
1134 args[n] = pf->pev->args[i];
1135 n++;
1136 }
1137 }
1138 return n;
1139 }
1140
1141 /* Add a found probe point into trace event list */
1142 static int add_probe_trace_event(Dwarf_Die *sc_die, struct probe_finder *pf)
1143 {
1144 struct trace_event_finder *tf =
1145 container_of(pf, struct trace_event_finder, pf);
1146 struct probe_trace_event *tev;
1147 struct perf_probe_arg *args;
1148 int ret, i;
1149
1150 /* Check number of tevs */
1151 if (tf->ntevs == tf->max_tevs) {
1152 pr_warning("Too many( > %d) probe point found.\n",
1153 tf->max_tevs);
1154 return -ERANGE;
1155 }
1156 tev = &tf->tevs[tf->ntevs++];
1157
1158 /* Trace point should be converted from subprogram DIE */
1159 ret = convert_to_trace_point(&pf->sp_die, tf->mod, pf->addr,
1160 pf->pev->point.retprobe, &tev->point);
1161 if (ret < 0)
1162 return ret;
1163
1164 pr_debug("Probe point found: %s+%lu\n", tev->point.symbol,
1165 tev->point.offset);
1166
1167 /* Expand special probe argument if exist */
1168 args = zalloc(sizeof(struct perf_probe_arg) * MAX_PROBE_ARGS);
1169 if (args == NULL)
1170 return -ENOMEM;
1171
1172 ret = expand_probe_args(sc_die, pf, args);
1173 if (ret < 0)
1174 goto end;
1175
1176 tev->nargs = ret;
1177 tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
1178 if (tev->args == NULL) {
1179 ret = -ENOMEM;
1180 goto end;
1181 }
1182
1183 /* Find each argument */
1184 for (i = 0; i < tev->nargs; i++) {
1185 pf->pvar = &args[i];
1186 pf->tvar = &tev->args[i];
1187 /* Variable should be found from scope DIE */
1188 ret = find_variable(sc_die, pf);
1189 if (ret != 0)
1190 break;
1191 }
1192
1193 end:
1194 free(args);
1195 return ret;
1196 }
1197
1198 /* Find probe_trace_events specified by perf_probe_event from debuginfo */
1199 int debuginfo__find_trace_events(struct debuginfo *dbg,
1200 struct perf_probe_event *pev,
1201 struct probe_trace_event **tevs, int max_tevs)
1202 {
1203 struct trace_event_finder tf = {
1204 .pf = {.pev = pev, .callback = add_probe_trace_event},
1205 .mod = dbg->mod, .max_tevs = max_tevs};
1206 int ret;
1207
1208 /* Allocate result tevs array */
1209 *tevs = zalloc(sizeof(struct probe_trace_event) * max_tevs);
1210 if (*tevs == NULL)
1211 return -ENOMEM;
1212
1213 tf.tevs = *tevs;
1214 tf.ntevs = 0;
1215
1216 ret = debuginfo__find_probes(dbg, &tf.pf);
1217 if (ret < 0) {
1218 zfree(tevs);
1219 return ret;
1220 }
1221
1222 return (ret < 0) ? ret : tf.ntevs;
1223 }
1224
1225 #define MAX_VAR_LEN 64
1226
1227 /* Collect available variables in this scope */
1228 static int collect_variables_cb(Dwarf_Die *die_mem, void *data)
1229 {
1230 struct available_var_finder *af = data;
1231 struct variable_list *vl;
1232 char buf[MAX_VAR_LEN];
1233 int tag, ret;
1234
1235 vl = &af->vls[af->nvls - 1];
1236
1237 tag = dwarf_tag(die_mem);
1238 if (tag == DW_TAG_formal_parameter ||
1239 tag == DW_TAG_variable) {
1240 ret = convert_variable_location(die_mem, af->pf.addr,
1241 af->pf.fb_ops, &af->pf.sp_die,
1242 NULL);
1243 if (ret == 0) {
1244 ret = die_get_varname(die_mem, buf, MAX_VAR_LEN);
1245 pr_debug2("Add new var: %s\n", buf);
1246 if (ret > 0)
1247 strlist__add(vl->vars, buf);
1248 }
1249 }
1250
1251 if (af->child && dwarf_haspc(die_mem, af->pf.addr))
1252 return DIE_FIND_CB_CONTINUE;
1253 else
1254 return DIE_FIND_CB_SIBLING;
1255 }
1256
1257 /* Add a found vars into available variables list */
1258 static int add_available_vars(Dwarf_Die *sc_die, struct probe_finder *pf)
1259 {
1260 struct available_var_finder *af =
1261 container_of(pf, struct available_var_finder, pf);
1262 struct variable_list *vl;
1263 Dwarf_Die die_mem;
1264 int ret;
1265
1266 /* Check number of tevs */
1267 if (af->nvls == af->max_vls) {
1268 pr_warning("Too many( > %d) probe point found.\n", af->max_vls);
1269 return -ERANGE;
1270 }
1271 vl = &af->vls[af->nvls++];
1272
1273 /* Trace point should be converted from subprogram DIE */
1274 ret = convert_to_trace_point(&pf->sp_die, af->mod, pf->addr,
1275 pf->pev->point.retprobe, &vl->point);
1276 if (ret < 0)
1277 return ret;
1278
1279 pr_debug("Probe point found: %s+%lu\n", vl->point.symbol,
1280 vl->point.offset);
1281
1282 /* Find local variables */
1283 vl->vars = strlist__new(true, NULL);
1284 if (vl->vars == NULL)
1285 return -ENOMEM;
1286 af->child = true;
1287 die_find_child(sc_die, collect_variables_cb, (void *)af, &die_mem);
1288
1289 /* Find external variables */
1290 if (!af->externs)
1291 goto out;
1292 /* Don't need to search child DIE for externs. */
1293 af->child = false;
1294 die_find_child(&pf->cu_die, collect_variables_cb, (void *)af, &die_mem);
1295
1296 out:
1297 if (strlist__empty(vl->vars)) {
1298 strlist__delete(vl->vars);
1299 vl->vars = NULL;
1300 }
1301
1302 return ret;
1303 }
1304
1305 /*
1306 * Find available variables at given probe point
1307 * Return the number of found probe points. Return 0 if there is no
1308 * matched probe point. Return <0 if an error occurs.
1309 */
1310 int debuginfo__find_available_vars_at(struct debuginfo *dbg,
1311 struct perf_probe_event *pev,
1312 struct variable_list **vls,
1313 int max_vls, bool externs)
1314 {
1315 struct available_var_finder af = {
1316 .pf = {.pev = pev, .callback = add_available_vars},
1317 .mod = dbg->mod,
1318 .max_vls = max_vls, .externs = externs};
1319 int ret;
1320
1321 /* Allocate result vls array */
1322 *vls = zalloc(sizeof(struct variable_list) * max_vls);
1323 if (*vls == NULL)
1324 return -ENOMEM;
1325
1326 af.vls = *vls;
1327 af.nvls = 0;
1328
1329 ret = debuginfo__find_probes(dbg, &af.pf);
1330 if (ret < 0) {
1331 /* Free vlist for error */
1332 while (af.nvls--) {
1333 zfree(&af.vls[af.nvls].point.symbol);
1334 strlist__delete(af.vls[af.nvls].vars);
1335 }
1336 zfree(vls);
1337 return ret;
1338 }
1339
1340 return (ret < 0) ? ret : af.nvls;
1341 }
1342
1343 /* Reverse search */
1344 int debuginfo__find_probe_point(struct debuginfo *dbg, unsigned long addr,
1345 struct perf_probe_point *ppt)
1346 {
1347 Dwarf_Die cudie, spdie, indie;
1348 Dwarf_Addr _addr = 0, baseaddr = 0;
1349 const char *fname = NULL, *func = NULL, *basefunc = NULL, *tmp;
1350 int baseline = 0, lineno = 0, ret = 0;
1351
1352 /* Adjust address with bias */
1353 addr += dbg->bias;
1354
1355 /* Find cu die */
1356 if (!dwarf_addrdie(dbg->dbg, (Dwarf_Addr)addr - dbg->bias, &cudie)) {
1357 pr_warning("Failed to find debug information for address %lx\n",
1358 addr);
1359 ret = -EINVAL;
1360 goto end;
1361 }
1362
1363 /* Find a corresponding line (filename and lineno) */
1364 cu_find_lineinfo(&cudie, addr, &fname, &lineno);
1365 /* Don't care whether it failed or not */
1366
1367 /* Find a corresponding function (name, baseline and baseaddr) */
1368 if (die_find_realfunc(&cudie, (Dwarf_Addr)addr, &spdie)) {
1369 /* Get function entry information */
1370 func = basefunc = dwarf_diename(&spdie);
1371 if (!func ||
1372 dwarf_entrypc(&spdie, &baseaddr) != 0 ||
1373 dwarf_decl_line(&spdie, &baseline) != 0) {
1374 lineno = 0;
1375 goto post;
1376 }
1377
1378 fname = dwarf_decl_file(&spdie);
1379 if (addr == (unsigned long)baseaddr) {
1380 /* Function entry - Relative line number is 0 */
1381 lineno = baseline;
1382 goto post;
1383 }
1384
1385 /* Track down the inline functions step by step */
1386 while (die_find_top_inlinefunc(&spdie, (Dwarf_Addr)addr,
1387 &indie)) {
1388 /* There is an inline function */
1389 if (dwarf_entrypc(&indie, &_addr) == 0 &&
1390 _addr == addr) {
1391 /*
1392 * addr is at an inline function entry.
1393 * In this case, lineno should be the call-site
1394 * line number. (overwrite lineinfo)
1395 */
1396 lineno = die_get_call_lineno(&indie);
1397 fname = die_get_call_file(&indie);
1398 break;
1399 } else {
1400 /*
1401 * addr is in an inline function body.
1402 * Since lineno points one of the lines
1403 * of the inline function, baseline should
1404 * be the entry line of the inline function.
1405 */
1406 tmp = dwarf_diename(&indie);
1407 if (!tmp ||
1408 dwarf_decl_line(&indie, &baseline) != 0)
1409 break;
1410 func = tmp;
1411 spdie = indie;
1412 }
1413 }
1414 /* Verify the lineno and baseline are in a same file */
1415 tmp = dwarf_decl_file(&spdie);
1416 if (!tmp || strcmp(tmp, fname) != 0)
1417 lineno = 0;
1418 }
1419
1420 post:
1421 /* Make a relative line number or an offset */
1422 if (lineno)
1423 ppt->line = lineno - baseline;
1424 else if (basefunc) {
1425 ppt->offset = addr - (unsigned long)baseaddr;
1426 func = basefunc;
1427 }
1428
1429 /* Duplicate strings */
1430 if (func) {
1431 ppt->function = strdup(func);
1432 if (ppt->function == NULL) {
1433 ret = -ENOMEM;
1434 goto end;
1435 }
1436 }
1437 if (fname) {
1438 ppt->file = strdup(fname);
1439 if (ppt->file == NULL) {
1440 zfree(&ppt->function);
1441 ret = -ENOMEM;
1442 goto end;
1443 }
1444 }
1445 end:
1446 if (ret == 0 && (fname || func))
1447 ret = 1; /* Found a point */
1448 return ret;
1449 }
1450
1451 /* Add a line and store the src path */
1452 static int line_range_add_line(const char *src, unsigned int lineno,
1453 struct line_range *lr)
1454 {
1455 /* Copy source path */
1456 if (!lr->path) {
1457 lr->path = strdup(src);
1458 if (lr->path == NULL)
1459 return -ENOMEM;
1460 }
1461 return intlist__add(lr->line_list, lineno);
1462 }
1463
1464 static int line_range_walk_cb(const char *fname, int lineno,
1465 Dwarf_Addr addr __maybe_unused,
1466 void *data)
1467 {
1468 struct line_finder *lf = data;
1469 int err;
1470
1471 if ((strtailcmp(fname, lf->fname) != 0) ||
1472 (lf->lno_s > lineno || lf->lno_e < lineno))
1473 return 0;
1474
1475 err = line_range_add_line(fname, lineno, lf->lr);
1476 if (err < 0 && err != -EEXIST)
1477 return err;
1478
1479 return 0;
1480 }
1481
1482 /* Find line range from its line number */
1483 static int find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf)
1484 {
1485 int ret;
1486
1487 ret = die_walk_lines(sp_die ?: &lf->cu_die, line_range_walk_cb, lf);
1488
1489 /* Update status */
1490 if (ret >= 0)
1491 if (!intlist__empty(lf->lr->line_list))
1492 ret = lf->found = 1;
1493 else
1494 ret = 0; /* Lines are not found */
1495 else {
1496 zfree(&lf->lr->path);
1497 }
1498 return ret;
1499 }
1500
1501 static int line_range_inline_cb(Dwarf_Die *in_die, void *data)
1502 {
1503 int ret = find_line_range_by_line(in_die, data);
1504
1505 /*
1506 * We have to check all instances of inlined function, because
1507 * some execution paths can be optimized out depends on the
1508 * function argument of instances. However, if an error occurs,
1509 * it should be handled by the caller.
1510 */
1511 return ret < 0 ? ret : 0;
1512 }
1513
1514 /* Search function definition from function name */
1515 static int line_range_search_cb(Dwarf_Die *sp_die, void *data)
1516 {
1517 struct dwarf_callback_param *param = data;
1518 struct line_finder *lf = param->data;
1519 struct line_range *lr = lf->lr;
1520
1521 /* Check declared file */
1522 if (lr->file && strtailcmp(lr->file, dwarf_decl_file(sp_die)))
1523 return DWARF_CB_OK;
1524
1525 if (die_is_func_def(sp_die) &&
1526 die_compare_name(sp_die, lr->function)) {
1527 lf->fname = dwarf_decl_file(sp_die);
1528 dwarf_decl_line(sp_die, &lr->offset);
1529 pr_debug("fname: %s, lineno:%d\n", lf->fname, lr->offset);
1530 lf->lno_s = lr->offset + lr->start;
1531 if (lf->lno_s < 0) /* Overflow */
1532 lf->lno_s = INT_MAX;
1533 lf->lno_e = lr->offset + lr->end;
1534 if (lf->lno_e < 0) /* Overflow */
1535 lf->lno_e = INT_MAX;
1536 pr_debug("New line range: %d to %d\n", lf->lno_s, lf->lno_e);
1537 lr->start = lf->lno_s;
1538 lr->end = lf->lno_e;
1539 if (dwarf_func_inline(sp_die))
1540 param->retval = die_walk_instances(sp_die,
1541 line_range_inline_cb, lf);
1542 else
1543 param->retval = find_line_range_by_line(sp_die, lf);
1544 return DWARF_CB_ABORT;
1545 }
1546 return DWARF_CB_OK;
1547 }
1548
1549 static int find_line_range_by_func(struct line_finder *lf)
1550 {
1551 struct dwarf_callback_param param = {.data = (void *)lf, .retval = 0};
1552 dwarf_getfuncs(&lf->cu_die, line_range_search_cb, &param, 0);
1553 return param.retval;
1554 }
1555
1556 int debuginfo__find_line_range(struct debuginfo *dbg, struct line_range *lr)
1557 {
1558 struct line_finder lf = {.lr = lr, .found = 0};
1559 int ret = 0;
1560 Dwarf_Off off = 0, noff;
1561 size_t cuhl;
1562 Dwarf_Die *diep;
1563 const char *comp_dir;
1564
1565 /* Fastpath: lookup by function name from .debug_pubnames section */
1566 if (lr->function) {
1567 struct pubname_callback_param pubname_param = {
1568 .function = lr->function, .file = lr->file,
1569 .cu_die = &lf.cu_die, .sp_die = &lf.sp_die, .found = 0};
1570 struct dwarf_callback_param line_range_param = {
1571 .data = (void *)&lf, .retval = 0};
1572
1573 dwarf_getpubnames(dbg->dbg, pubname_search_cb,
1574 &pubname_param, 0);
1575 if (pubname_param.found) {
1576 line_range_search_cb(&lf.sp_die, &line_range_param);
1577 if (lf.found)
1578 goto found;
1579 }
1580 }
1581
1582 /* Loop on CUs (Compilation Unit) */
1583 while (!lf.found && ret >= 0) {
1584 if (dwarf_nextcu(dbg->dbg, off, &noff, &cuhl,
1585 NULL, NULL, NULL) != 0)
1586 break;
1587
1588 /* Get the DIE(Debugging Information Entry) of this CU */
1589 diep = dwarf_offdie(dbg->dbg, off + cuhl, &lf.cu_die);
1590 if (!diep)
1591 continue;
1592
1593 /* Check if target file is included. */
1594 if (lr->file)
1595 lf.fname = cu_find_realpath(&lf.cu_die, lr->file);
1596 else
1597 lf.fname = 0;
1598
1599 if (!lr->file || lf.fname) {
1600 if (lr->function)
1601 ret = find_line_range_by_func(&lf);
1602 else {
1603 lf.lno_s = lr->start;
1604 lf.lno_e = lr->end;
1605 ret = find_line_range_by_line(NULL, &lf);
1606 }
1607 }
1608 off = noff;
1609 }
1610
1611 found:
1612 /* Store comp_dir */
1613 if (lf.found) {
1614 comp_dir = cu_get_comp_dir(&lf.cu_die);
1615 if (comp_dir) {
1616 lr->comp_dir = strdup(comp_dir);
1617 if (!lr->comp_dir)
1618 ret = -ENOMEM;
1619 }
1620 }
1621
1622 pr_debug("path: %s\n", lr->path);
1623 return (ret < 0) ? ret : lf.found;
1624 }
1625
Linux with added FPC-III support