1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * probe-finder.c : C expression to kprobe event converter
5 * Written by Masami Hiramatsu <mhiramat@redhat.com>
9 #include <sys/utsname.h>
10 #include <sys/types.h>
19 #include <dwarf-regs.h>
21 #include <linux/bitops.h>
22 #include <linux/zalloc.h>
30 #include "probe-finder.h"
31 #include "probe-file.h"
34 #ifdef HAVE_DEBUGINFOD_SUPPORT
35 #include <elfutils/debuginfod.h>
38 /* Kprobe tracer basic type is up to u64 */
39 #define MAX_BASIC_TYPE_BITS 64
41 /* Dwarf FL wrappers */
42 static char *debuginfo_path; /* Currently dummy */
44 static const Dwfl_Callbacks offline_callbacks = {
45 .find_debuginfo = dwfl_standard_find_debuginfo,
46 .debuginfo_path = &debuginfo_path,
48 .section_address = dwfl_offline_section_address,
50 /* We use this table for core files too. */
51 .find_elf = dwfl_build_id_find_elf,
54 /* Get a Dwarf from offline image */
55 static int debuginfo__init_offline_dwarf(struct debuginfo *dbg,
61 fd = open(path, O_RDONLY);
65 dbg->dwfl = dwfl_begin(&offline_callbacks);
69 dwfl_report_begin(dbg->dwfl);
70 dbg->mod = dwfl_report_offline(dbg->dwfl, "", "", fd);
74 dbg->dbg = dwfl_module_getdwarf(dbg->mod, &dbg->bias);
78 dwfl_module_build_id(dbg->mod, &dbg->build_id, &dummy);
80 dwfl_report_end(dbg->dwfl, NULL, NULL);
88 memset(dbg, 0, sizeof(*dbg));
93 static struct debuginfo *__debuginfo__new(const char *path)
95 struct debuginfo *dbg = zalloc(sizeof(*dbg));
99 if (debuginfo__init_offline_dwarf(dbg, path) < 0)
102 pr_debug("Open Debuginfo file: %s\n", path);
106 enum dso_binary_type distro_dwarf_types[] = {
107 DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
108 DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
109 DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
110 DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
111 DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO,
112 DSO_BINARY_TYPE__NOT_FOUND,
115 struct debuginfo *debuginfo__new(const char *path)
117 enum dso_binary_type *type;
118 char buf[PATH_MAX], nil = '\0';
120 struct debuginfo *dinfo = NULL;
122 /* Try to open distro debuginfo files */
123 dso = dso__new(path);
127 for (type = distro_dwarf_types;
128 !dinfo && *type != DSO_BINARY_TYPE__NOT_FOUND;
130 if (dso__read_binary_type_filename(dso, *type, &nil,
133 dinfo = __debuginfo__new(buf);
138 /* if failed to open all distro debuginfo, open given binary */
139 return dinfo ? : __debuginfo__new(path);
142 void debuginfo__delete(struct debuginfo *dbg)
152 * Probe finder related functions
155 static struct probe_trace_arg_ref *alloc_trace_arg_ref(long offs)
157 struct probe_trace_arg_ref *ref;
158 ref = zalloc(sizeof(struct probe_trace_arg_ref));
165 * Convert a location into trace_arg.
166 * If tvar == NULL, this just checks variable can be converted.
167 * If fentry == true and vr_die is a parameter, do heuristic search
168 * for the location fuzzed by function entry mcount.
170 static int convert_variable_location(Dwarf_Die *vr_die, Dwarf_Addr addr,
171 Dwarf_Op *fb_ops, Dwarf_Die *sp_die,
172 unsigned int machine,
173 struct probe_trace_arg *tvar)
175 Dwarf_Attribute attr;
185 if (dwarf_attr(vr_die, DW_AT_external, &attr) != NULL)
189 if (dwarf_attr(vr_die, DW_AT_const_value, &attr) &&
190 immediate_value_is_supported()) {
196 dwarf_formsdata(&attr, &snum);
197 ret = asprintf(&tvar->value, "\\%ld", (long)snum);
199 return ret < 0 ? -ENOMEM : 0;
202 /* TODO: handle more than 1 exprs */
203 if (dwarf_attr(vr_die, DW_AT_location, &attr) == NULL)
204 return -EINVAL; /* Broken DIE ? */
205 if (dwarf_getlocation_addr(&attr, addr, &op, &nops, 1) <= 0) {
206 ret = dwarf_entrypc(sp_die, &tmp);
210 if (probe_conf.show_location_range &&
211 (dwarf_tag(vr_die) == DW_TAG_variable)) {
213 } else if (addr != tmp ||
214 dwarf_tag(vr_die) != DW_TAG_formal_parameter) {
218 ret = dwarf_highpc(sp_die, &tmp);
222 * This is fuzzed by fentry mcount. We try to find the
223 * parameter location at the earliest address.
225 for (addr += 1; addr <= tmp; addr++) {
226 if (dwarf_getlocation_addr(&attr, addr, &op,
234 /* TODO: Support const_value */
237 if (op->atom == DW_OP_addr) {
241 /* Static variables on memory (not stack), make @varname */
242 ret = strlen(dwarf_diename(vr_die));
243 tvar->value = zalloc(ret + 2);
244 if (tvar->value == NULL)
246 snprintf(tvar->value, ret + 2, "@%s", dwarf_diename(vr_die));
247 tvar->ref = alloc_trace_arg_ref((long)offs);
248 if (tvar->ref == NULL)
253 /* If this is based on frame buffer, set the offset */
254 if (op->atom == DW_OP_fbreg) {
262 if (op->atom >= DW_OP_breg0 && op->atom <= DW_OP_breg31) {
263 regn = op->atom - DW_OP_breg0;
266 } else if (op->atom >= DW_OP_reg0 && op->atom <= DW_OP_reg31) {
267 regn = op->atom - DW_OP_reg0;
268 } else if (op->atom == DW_OP_bregx) {
272 } else if (op->atom == DW_OP_regx) {
275 pr_debug("DW_OP %x is not supported.\n", op->atom);
282 regs = get_dwarf_regstr(regn, machine);
284 /* This should be a bug in DWARF or this tool */
285 pr_warning("Mapping for the register number %u "
286 "missing on this architecture.\n", regn);
290 tvar->value = strdup(regs);
291 if (tvar->value == NULL)
295 tvar->ref = alloc_trace_arg_ref((long)offs);
296 if (tvar->ref == NULL)
302 #define BYTES_TO_BITS(nb) ((nb) * BITS_PER_LONG / sizeof(long))
304 static int convert_variable_type(Dwarf_Die *vr_die,
305 struct probe_trace_arg *tvar,
306 const char *cast, bool user_access)
308 struct probe_trace_arg_ref **ref_ptr = &tvar->ref;
311 char sbuf[STRERR_BUFSIZE];
312 int bsize, boffs, total;
316 /* TODO: check all types */
317 if (cast && strcmp(cast, "string") != 0 && strcmp(cast, "ustring") &&
318 strcmp(cast, "x") != 0 &&
319 strcmp(cast, "s") != 0 && strcmp(cast, "u") != 0) {
320 /* Non string type is OK */
321 /* and respect signedness/hexadecimal cast */
322 tvar->type = strdup(cast);
323 return (tvar->type == NULL) ? -ENOMEM : 0;
326 bsize = dwarf_bitsize(vr_die);
328 /* This is a bitfield */
329 boffs = dwarf_bitoffset(vr_die);
330 total = dwarf_bytesize(vr_die);
331 if (boffs < 0 || total < 0)
333 ret = snprintf(buf, 16, "b%d@%d/%zd", bsize, boffs,
334 BYTES_TO_BITS(total));
338 if (die_get_real_type(vr_die, &type) == NULL) {
339 pr_warning("Failed to get a type information of %s.\n",
340 dwarf_diename(vr_die));
344 pr_debug("%s type is %s.\n",
345 dwarf_diename(vr_die), dwarf_diename(&type));
347 if (cast && (!strcmp(cast, "string") || !strcmp(cast, "ustring"))) {
349 ret = dwarf_tag(&type);
350 if (ret != DW_TAG_pointer_type &&
351 ret != DW_TAG_array_type) {
352 pr_warning("Failed to cast into string: "
353 "%s(%s) is not a pointer nor array.\n",
354 dwarf_diename(vr_die), dwarf_diename(&type));
357 if (die_get_real_type(&type, &type) == NULL) {
358 pr_warning("Failed to get a type"
362 if (ret == DW_TAG_pointer_type) {
364 ref_ptr = &(*ref_ptr)->next;
365 /* Add new reference with offset +0 */
366 *ref_ptr = zalloc(sizeof(struct probe_trace_arg_ref));
367 if (*ref_ptr == NULL) {
368 pr_warning("Out of memory error\n");
371 (*ref_ptr)->user_access = user_access;
373 if (!die_compare_name(&type, "char") &&
374 !die_compare_name(&type, "unsigned char")) {
375 pr_warning("Failed to cast into string: "
376 "%s is not (unsigned) char *.\n",
377 dwarf_diename(vr_die));
380 tvar->type = strdup(cast);
381 return (tvar->type == NULL) ? -ENOMEM : 0;
384 if (cast && (strcmp(cast, "u") == 0))
386 else if (cast && (strcmp(cast, "s") == 0))
388 else if (cast && (strcmp(cast, "x") == 0) &&
389 probe_type_is_available(PROBE_TYPE_X))
392 prefix = die_is_signed_type(&type) ? 's' :
393 probe_type_is_available(PROBE_TYPE_X) ? 'x' : 'u';
395 ret = dwarf_bytesize(&type);
397 /* No size ... try to use default type */
399 ret = BYTES_TO_BITS(ret);
401 /* Check the bitwidth */
402 if (ret > MAX_BASIC_TYPE_BITS) {
403 pr_info("%s exceeds max-bitwidth. Cut down to %d bits.\n",
404 dwarf_diename(&type), MAX_BASIC_TYPE_BITS);
405 ret = MAX_BASIC_TYPE_BITS;
407 ret = snprintf(buf, 16, "%c%d", prefix, ret);
410 if (ret < 0 || ret >= 16) {
413 pr_warning("Failed to convert variable type: %s\n",
414 str_error_r(-ret, sbuf, sizeof(sbuf)));
417 tvar->type = strdup(buf);
418 if (tvar->type == NULL)
423 static int convert_variable_fields(Dwarf_Die *vr_die, const char *varname,
424 struct perf_probe_arg_field *field,
425 struct probe_trace_arg_ref **ref_ptr,
426 Dwarf_Die *die_mem, bool user_access)
428 struct probe_trace_arg_ref *ref = *ref_ptr;
433 pr_debug("converting %s in %s\n", field->name, varname);
434 if (die_get_real_type(vr_die, &type) == NULL) {
435 pr_warning("Failed to get the type of %s.\n", varname);
438 pr_debug2("Var real type: %s (%x)\n", dwarf_diename(&type),
439 (unsigned)dwarf_dieoffset(&type));
440 tag = dwarf_tag(&type);
442 if (field->name[0] == '[' &&
443 (tag == DW_TAG_array_type || tag == DW_TAG_pointer_type)) {
444 /* Save original type for next field or type */
445 memcpy(die_mem, &type, sizeof(*die_mem));
446 /* Get the type of this array */
447 if (die_get_real_type(&type, &type) == NULL) {
448 pr_warning("Failed to get the type of %s.\n", varname);
451 pr_debug2("Array real type: %s (%x)\n", dwarf_diename(&type),
452 (unsigned)dwarf_dieoffset(&type));
453 if (tag == DW_TAG_pointer_type) {
454 ref = zalloc(sizeof(struct probe_trace_arg_ref));
458 (*ref_ptr)->next = ref;
462 ref->offset += dwarf_bytesize(&type) * field->index;
463 ref->user_access = user_access;
465 } else if (tag == DW_TAG_pointer_type) {
466 /* Check the pointer and dereference */
468 pr_err("Semantic error: %s must be referred by '->'\n",
472 /* Get the type pointed by this pointer */
473 if (die_get_real_type(&type, &type) == NULL) {
474 pr_warning("Failed to get the type of %s.\n", varname);
477 /* Verify it is a data structure */
478 tag = dwarf_tag(&type);
479 if (tag != DW_TAG_structure_type && tag != DW_TAG_union_type) {
480 pr_warning("%s is not a data structure nor a union.\n",
485 ref = zalloc(sizeof(struct probe_trace_arg_ref));
489 (*ref_ptr)->next = ref;
493 /* Verify it is a data structure */
494 if (tag != DW_TAG_structure_type && tag != DW_TAG_union_type) {
495 pr_warning("%s is not a data structure nor a union.\n",
499 if (field->name[0] == '[') {
500 pr_err("Semantic error: %s is not a pointer"
501 " nor array.\n", varname);
504 /* While processing unnamed field, we don't care about this */
505 if (field->ref && dwarf_diename(vr_die)) {
506 pr_err("Semantic error: %s must be referred by '.'\n",
511 pr_warning("Structure on a register is not "
517 if (die_find_member(&type, field->name, die_mem) == NULL) {
518 pr_warning("%s(type:%s) has no member %s.\n", varname,
519 dwarf_diename(&type), field->name);
523 /* Get the offset of the field */
524 if (tag == DW_TAG_union_type) {
527 ret = die_get_data_member_location(die_mem, &offs);
529 pr_warning("Failed to get the offset of %s.\n",
534 ref->offset += (long)offs;
535 ref->user_access = user_access;
537 /* If this member is unnamed, we need to reuse this field */
538 if (!dwarf_diename(die_mem))
539 return convert_variable_fields(die_mem, varname, field,
540 &ref, die_mem, user_access);
543 /* Converting next field */
545 return convert_variable_fields(die_mem, field->name,
546 field->next, &ref, die_mem, user_access);
551 static void print_var_not_found(const char *varname)
553 pr_err("Failed to find the location of the '%s' variable at this address.\n"
554 " Perhaps it has been optimized out.\n"
555 " Use -V with the --range option to show '%s' location range.\n",
559 /* Show a variables in kprobe event format */
560 static int convert_variable(Dwarf_Die *vr_die, struct probe_finder *pf)
565 pr_debug("Converting variable %s into trace event.\n",
566 dwarf_diename(vr_die));
568 ret = convert_variable_location(vr_die, pf->addr, pf->fb_ops,
569 &pf->sp_die, pf->machine, pf->tvar);
570 if (ret == -ENOENT && pf->skip_empty_arg)
571 /* This can be found in other place. skip it */
573 if (ret == -ENOENT || ret == -EINVAL) {
574 print_var_not_found(pf->pvar->var);
575 } else if (ret == -ENOTSUP)
576 pr_err("Sorry, we don't support this variable location yet.\n");
577 else if (ret == 0 && pf->pvar->field) {
578 ret = convert_variable_fields(vr_die, pf->pvar->var,
579 pf->pvar->field, &pf->tvar->ref,
580 &die_mem, pf->pvar->user_access);
584 ret = convert_variable_type(vr_die, pf->tvar, pf->pvar->type,
585 pf->pvar->user_access);
586 /* *expr will be cached in libdw. Don't free it. */
590 /* Find a variable in a scope DIE */
591 static int find_variable(Dwarf_Die *sc_die, struct probe_finder *pf)
597 /* Copy raw parameters */
598 if (!is_c_varname(pf->pvar->var))
599 return copy_to_probe_trace_arg(pf->tvar, pf->pvar);
602 pf->tvar->name = strdup(pf->pvar->name);
604 buf = synthesize_perf_probe_arg(pf->pvar);
607 ptr = strchr(buf, ':'); /* Change type separator to _ */
610 pf->tvar->name = buf;
612 if (pf->tvar->name == NULL)
615 pr_debug("Searching '%s' variable in context.\n", pf->pvar->var);
616 /* Search child die for local variables and parameters. */
617 if (!die_find_variable_at(sc_die, pf->pvar->var, pf->addr, &vr_die)) {
618 /* Search again in global variables */
619 if (!die_find_variable_at(&pf->cu_die, pf->pvar->var,
621 if (pf->skip_empty_arg)
623 pr_warning("Failed to find '%s' in this function.\n",
629 ret = convert_variable(&vr_die, pf);
634 /* Convert subprogram DIE to trace point */
635 static int convert_to_trace_point(Dwarf_Die *sp_die, Dwfl_Module *mod,
636 Dwarf_Addr paddr, bool retprobe,
637 const char *function,
638 struct probe_trace_point *tp)
644 /* Verify the address is correct */
645 if (!dwarf_haspc(sp_die, paddr)) {
646 pr_warning("Specified offset is out of %s\n",
647 dwarf_diename(sp_die));
651 if (dwarf_entrypc(sp_die, &eaddr) == 0) {
652 /* If the DIE has entrypc, use it. */
653 symbol = dwarf_diename(sp_die);
655 /* Try to get actual symbol name and address from symtab */
656 symbol = dwfl_module_addrsym(mod, paddr, &sym, NULL);
657 eaddr = sym.st_value;
660 pr_warning("Failed to find symbol at 0x%lx\n",
661 (unsigned long)paddr);
665 tp->offset = (unsigned long)(paddr - eaddr);
666 tp->address = (unsigned long)paddr;
667 tp->symbol = strdup(symbol);
671 /* Return probe must be on the head of a subprogram */
673 if (eaddr != paddr) {
674 pr_warning("Failed to find \"%s%%return\",\n"
675 " because %s is an inlined function and"
676 " has no return point.\n", function,
686 /* Call probe_finder callback with scope DIE */
687 static int call_probe_finder(Dwarf_Die *sc_die, struct probe_finder *pf)
689 Dwarf_Attribute fb_attr;
690 Dwarf_Frame *frame = NULL;
695 pr_err("Caller must pass a scope DIE. Program error.\n");
699 /* If not a real subprogram, find a real one */
700 if (!die_is_func_def(sc_die)) {
701 if (!die_find_realfunc(&pf->cu_die, pf->addr, &pf->sp_die)) {
702 if (die_find_tailfunc(&pf->cu_die, pf->addr, &pf->sp_die)) {
703 pr_warning("Ignoring tail call from %s\n",
704 dwarf_diename(&pf->sp_die));
707 pr_warning("Failed to find probe point in any "
713 memcpy(&pf->sp_die, sc_die, sizeof(Dwarf_Die));
715 /* Get the frame base attribute/ops from subprogram */
716 dwarf_attr(&pf->sp_die, DW_AT_frame_base, &fb_attr);
717 ret = dwarf_getlocation_addr(&fb_attr, pf->addr, &pf->fb_ops, &nops, 1);
718 if (ret <= 0 || nops == 0) {
720 #if _ELFUTILS_PREREQ(0, 142)
721 } else if (nops == 1 && pf->fb_ops[0].atom == DW_OP_call_frame_cfa &&
722 (pf->cfi_eh != NULL || pf->cfi_dbg != NULL)) {
723 if ((dwarf_cfi_addrframe(pf->cfi_eh, pf->addr, &frame) != 0 &&
724 (dwarf_cfi_addrframe(pf->cfi_dbg, pf->addr, &frame) != 0)) ||
725 dwarf_frame_cfa(frame, &pf->fb_ops, &nops) != 0) {
726 pr_warning("Failed to get call frame on 0x%jx\n",
727 (uintmax_t)pf->addr);
734 /* Call finder's callback handler */
735 ret = pf->callback(sc_die, pf);
737 /* Since *pf->fb_ops can be a part of frame. we should free it here. */
744 struct find_scope_param {
745 const char *function;
753 static int find_best_scope_cb(Dwarf_Die *fn_die, void *data)
755 struct find_scope_param *fsp = data;
759 /* Skip if declared file name does not match */
761 file = dwarf_decl_file(fn_die);
762 if (!file || strcmp(fsp->file, file) != 0)
765 /* If the function name is given, that's what user expects */
767 if (die_match_name(fn_die, fsp->function)) {
768 memcpy(fsp->die_mem, fn_die, sizeof(Dwarf_Die));
773 /* With the line number, find the nearest declared DIE */
774 dwarf_decl_line(fn_die, &lno);
775 if (lno < fsp->line && fsp->diff > fsp->line - lno) {
776 /* Keep a candidate and continue */
777 fsp->diff = fsp->line - lno;
778 memcpy(fsp->die_mem, fn_die, sizeof(Dwarf_Die));
785 /* Return innermost DIE */
786 static int find_inner_scope_cb(Dwarf_Die *fn_die, void *data)
788 struct find_scope_param *fsp = data;
790 memcpy(fsp->die_mem, fn_die, sizeof(Dwarf_Die));
795 /* Find an appropriate scope fits to given conditions */
796 static Dwarf_Die *find_best_scope(struct probe_finder *pf, Dwarf_Die *die_mem)
798 struct find_scope_param fsp = {
799 .function = pf->pev->point.function,
808 ret = cu_walk_functions_at(&pf->cu_die, pf->addr, find_best_scope_cb,
810 if (!ret && !fsp.found)
811 cu_walk_functions_at(&pf->cu_die, pf->addr,
812 find_inner_scope_cb, &fsp);
814 return fsp.found ? die_mem : NULL;
817 static int verify_representive_line(struct probe_finder *pf, const char *fname,
818 int lineno, Dwarf_Addr addr)
820 const char *__fname, *__func = NULL;
824 /* Verify line number and address by reverse search */
825 if (cu_find_lineinfo(&pf->cu_die, addr, &__fname, &__lineno) < 0)
828 pr_debug2("Reversed line: %s:%d\n", __fname, __lineno);
829 if (strcmp(fname, __fname) || lineno == __lineno)
832 pr_warning("This line is sharing the address with other lines.\n");
834 if (pf->pev->point.function) {
835 /* Find best match function name and lines */
837 if (find_best_scope(pf, &die_mem)
838 && die_match_name(&die_mem, pf->pev->point.function)
839 && dwarf_decl_line(&die_mem, &lineno) == 0) {
840 __func = dwarf_diename(&die_mem);
844 pr_warning("Please try to probe at %s:%d instead.\n",
845 __func ? : __fname, __lineno);
850 static int probe_point_line_walker(const char *fname, int lineno,
851 Dwarf_Addr addr, void *data)
853 struct probe_finder *pf = data;
854 Dwarf_Die *sc_die, die_mem;
857 if (lineno != pf->lno || strtailcmp(fname, pf->fname) != 0)
860 if (verify_representive_line(pf, fname, lineno, addr))
864 sc_die = find_best_scope(pf, &die_mem);
866 pr_warning("Failed to find scope of probe point.\n");
870 ret = call_probe_finder(sc_die, pf);
872 /* Continue if no error, because the line will be in inline function */
873 return ret < 0 ? ret : 0;
876 /* Find probe point from its line number */
877 static int find_probe_point_by_line(struct probe_finder *pf)
879 return die_walk_lines(&pf->cu_die, probe_point_line_walker, pf);
882 /* Find lines which match lazy pattern */
883 static int find_lazy_match_lines(struct intlist *list,
884 const char *fname, const char *pat)
890 int count = 0, linenum = 1;
891 char sbuf[STRERR_BUFSIZE];
893 fp = fopen(fname, "r");
895 pr_warning("Failed to open %s: %s\n", fname,
896 str_error_r(errno, sbuf, sizeof(sbuf)));
900 while ((len = getline(&line, &line_len, fp)) > 0) {
902 if (line[len - 1] == '\n')
903 line[len - 1] = '\0';
905 if (strlazymatch(line, pat)) {
906 intlist__add(list, linenum);
918 pr_debug("No matched lines found in %s.\n", fname);
922 static int probe_point_lazy_walker(const char *fname, int lineno,
923 Dwarf_Addr addr, void *data)
925 struct probe_finder *pf = data;
926 Dwarf_Die *sc_die, die_mem;
929 if (!intlist__has_entry(pf->lcache, lineno) ||
930 strtailcmp(fname, pf->fname) != 0)
933 pr_debug("Probe line found: line:%d addr:0x%llx\n",
934 lineno, (unsigned long long)addr);
937 sc_die = find_best_scope(pf, &die_mem);
939 pr_warning("Failed to find scope of probe point.\n");
943 ret = call_probe_finder(sc_die, pf);
946 * Continue if no error, because the lazy pattern will match
949 return ret < 0 ? ret : 0;
952 /* Find probe points from lazy pattern */
953 static int find_probe_point_lazy(Dwarf_Die *sp_die, struct probe_finder *pf)
956 char sbuild_id[SBUILD_ID_SIZE] = "";
960 if (intlist__empty(pf->lcache)) {
961 const char *comp_dir;
963 comp_dir = cu_get_comp_dir(&pf->cu_die);
964 if (pf->dbg->build_id) {
965 build_id__init(&bid, pf->dbg->build_id, BUILD_ID_SIZE);
966 build_id__sprintf(&bid, sbuild_id);
968 ret = find_source_path(pf->fname, sbuild_id, comp_dir, &fpath);
970 pr_warning("Failed to find source file path.\n");
974 /* Matching lazy line pattern */
975 ret = find_lazy_match_lines(pf->lcache, fpath,
976 pf->pev->point.lazy_line);
982 return die_walk_lines(sp_die, probe_point_lazy_walker, pf);
985 static void skip_prologue(Dwarf_Die *sp_die, struct probe_finder *pf)
987 struct perf_probe_point *pp = &pf->pev->point;
990 if (!pf->pev->uprobes)
993 /* Compiled with optimization? */
994 if (die_is_optimized_target(&pf->cu_die))
997 /* Don't know entrypc? */
1001 /* Only FUNC and FUNC@SRC are eligible. */
1002 if (!pp->function || pp->line || pp->retprobe || pp->lazy_line ||
1003 pp->offset || pp->abs_address)
1006 /* Not interested in func parameter? */
1007 if (!perf_probe_with_var(pf->pev))
1010 pr_info("Target program is compiled without optimization. Skipping prologue.\n"
1011 "Probe on address 0x%" PRIx64 " to force probing at the function entry.\n\n",
1014 die_skip_prologue(sp_die, &pf->cu_die, &pf->addr);
1017 static int probe_point_inline_cb(Dwarf_Die *in_die, void *data)
1019 struct probe_finder *pf = data;
1020 struct perf_probe_point *pp = &pf->pev->point;
1025 ret = find_probe_point_lazy(in_die, pf);
1027 /* Get probe address */
1028 if (die_entrypc(in_die, &addr) != 0) {
1029 pr_warning("Failed to get entry address of %s.\n",
1030 dwarf_diename(in_die));
1034 pr_debug("%s has no valid entry address. skipped.\n",
1035 dwarf_diename(in_die));
1039 pf->addr += pp->offset;
1040 pr_debug("found inline addr: 0x%jx\n",
1041 (uintmax_t)pf->addr);
1043 ret = call_probe_finder(in_die, pf);
1049 /* Callback parameter with return value for libdw */
1050 struct dwarf_callback_param {
1055 /* Search function from function name */
1056 static int probe_point_search_cb(Dwarf_Die *sp_die, void *data)
1058 struct dwarf_callback_param *param = data;
1059 struct probe_finder *pf = param->data;
1060 struct perf_probe_point *pp = &pf->pev->point;
1062 /* Check tag and diename */
1063 if (!die_is_func_def(sp_die) ||
1064 !die_match_name(sp_die, pp->function))
1067 /* Check declared file */
1068 if (pp->file && strtailcmp(pp->file, dwarf_decl_file(sp_die)))
1071 pr_debug("Matched function: %s [%lx]\n", dwarf_diename(sp_die),
1072 (unsigned long)dwarf_dieoffset(sp_die));
1073 pf->fname = dwarf_decl_file(sp_die);
1074 if (pp->line) { /* Function relative line */
1075 dwarf_decl_line(sp_die, &pf->lno);
1076 pf->lno += pp->line;
1077 param->retval = find_probe_point_by_line(pf);
1078 } else if (die_is_func_instance(sp_die)) {
1079 /* Instances always have the entry address */
1080 die_entrypc(sp_die, &pf->addr);
1081 /* But in some case the entry address is 0 */
1082 if (pf->addr == 0) {
1083 pr_debug("%s has no entry PC. Skipped\n",
1084 dwarf_diename(sp_die));
1087 } else if (pp->lazy_line)
1088 param->retval = find_probe_point_lazy(sp_die, pf);
1090 skip_prologue(sp_die, pf);
1091 pf->addr += pp->offset;
1092 /* TODO: Check the address in this function */
1093 param->retval = call_probe_finder(sp_die, pf);
1095 } else if (!probe_conf.no_inlines) {
1096 /* Inlined function: search instances */
1097 param->retval = die_walk_instances(sp_die,
1098 probe_point_inline_cb, (void *)pf);
1099 /* This could be a non-existed inline definition */
1100 if (param->retval == -ENOENT)
1104 /* We need to find other candidates */
1105 if (strisglob(pp->function) && param->retval >= 0) {
1106 param->retval = 0; /* We have to clear the result */
1110 return DWARF_CB_ABORT; /* Exit; no same symbol in this CU. */
1113 static int find_probe_point_by_func(struct probe_finder *pf)
1115 struct dwarf_callback_param _param = {.data = (void *)pf,
1117 dwarf_getfuncs(&pf->cu_die, probe_point_search_cb, &_param, 0);
1118 return _param.retval;
1121 struct pubname_callback_param {
1129 static int pubname_search_cb(Dwarf *dbg, Dwarf_Global *gl, void *data)
1131 struct pubname_callback_param *param = data;
1133 if (dwarf_offdie(dbg, gl->die_offset, param->sp_die)) {
1134 if (dwarf_tag(param->sp_die) != DW_TAG_subprogram)
1137 if (die_match_name(param->sp_die, param->function)) {
1138 if (!dwarf_offdie(dbg, gl->cu_offset, param->cu_die))
1142 strtailcmp(param->file, dwarf_decl_file(param->sp_die)))
1146 return DWARF_CB_ABORT;
1153 static int debuginfo__find_probe_location(struct debuginfo *dbg,
1154 struct probe_finder *pf)
1156 struct perf_probe_point *pp = &pf->pev->point;
1157 Dwarf_Off off, noff;
1163 pf->lcache = intlist__new(NULL);
1167 /* Fastpath: lookup by function name from .debug_pubnames section */
1168 if (pp->function && !strisglob(pp->function)) {
1169 struct pubname_callback_param pubname_param = {
1170 .function = pp->function,
1172 .cu_die = &pf->cu_die,
1173 .sp_die = &pf->sp_die,
1176 struct dwarf_callback_param probe_param = {
1180 dwarf_getpubnames(dbg->dbg, pubname_search_cb,
1182 if (pubname_param.found) {
1183 ret = probe_point_search_cb(&pf->sp_die, &probe_param);
1189 /* Loop on CUs (Compilation Unit) */
1190 while (!dwarf_nextcu(dbg->dbg, off, &noff, &cuhl, NULL, NULL, NULL)) {
1191 /* Get the DIE(Debugging Information Entry) of this CU */
1192 diep = dwarf_offdie(dbg->dbg, off + cuhl, &pf->cu_die);
1198 /* Check if target file is included. */
1200 pf->fname = cu_find_realpath(&pf->cu_die, pp->file);
1204 if (!pp->file || pf->fname) {
1206 ret = find_probe_point_by_func(pf);
1207 else if (pp->lazy_line)
1208 ret = find_probe_point_lazy(&pf->cu_die, pf);
1211 ret = find_probe_point_by_line(pf);
1220 intlist__delete(pf->lcache);
1226 /* Find probe points from debuginfo */
1227 static int debuginfo__find_probes(struct debuginfo *dbg,
1228 struct probe_finder *pf)
1234 if (pf->cfi_eh || pf->cfi_dbg)
1235 return debuginfo__find_probe_location(dbg, pf);
1237 /* Get the call frame information from this dwarf */
1238 elf = dwarf_getelf(dbg->dbg);
1242 if (gelf_getehdr(elf, &ehdr) == NULL)
1245 pf->machine = ehdr.e_machine;
1247 #if _ELFUTILS_PREREQ(0, 142)
1251 if (elf_section_by_name(elf, &ehdr, &shdr, ".eh_frame", NULL) &&
1252 shdr.sh_type == SHT_PROGBITS)
1253 pf->cfi_eh = dwarf_getcfi_elf(elf);
1255 pf->cfi_dbg = dwarf_getcfi(dbg->dbg);
1259 ret = debuginfo__find_probe_location(dbg, pf);
1263 struct local_vars_finder {
1264 struct probe_finder *pf;
1265 struct perf_probe_arg *args;
1272 /* Collect available variables in this scope */
1273 static int copy_variables_cb(Dwarf_Die *die_mem, void *data)
1275 struct local_vars_finder *vf = data;
1276 struct probe_finder *pf = vf->pf;
1279 tag = dwarf_tag(die_mem);
1280 if (tag == DW_TAG_formal_parameter ||
1281 (tag == DW_TAG_variable && vf->vars)) {
1282 if (convert_variable_location(die_mem, vf->pf->addr,
1283 vf->pf->fb_ops, &pf->sp_die,
1284 pf->machine, NULL) == 0) {
1285 vf->args[vf->nargs].var = (char *)dwarf_diename(die_mem);
1286 if (vf->args[vf->nargs].var == NULL) {
1288 return DIE_FIND_CB_END;
1290 pr_debug(" %s", vf->args[vf->nargs].var);
1295 if (dwarf_haspc(die_mem, vf->pf->addr))
1296 return DIE_FIND_CB_CONTINUE;
1298 return DIE_FIND_CB_SIBLING;
1301 static int expand_probe_args(Dwarf_Die *sc_die, struct probe_finder *pf,
1302 struct perf_probe_arg *args)
1307 struct local_vars_finder vf = {.pf = pf, .args = args, .vars = false,
1308 .max_args = MAX_PROBE_ARGS, .ret = 0};
1310 for (i = 0; i < pf->pev->nargs; i++) {
1311 /* var never be NULL */
1312 if (strcmp(pf->pev->args[i].var, PROBE_ARG_VARS) == 0)
1314 else if (strcmp(pf->pev->args[i].var, PROBE_ARG_PARAMS) != 0) {
1315 /* Copy normal argument */
1316 args[n] = pf->pev->args[i];
1320 pr_debug("Expanding %s into:", pf->pev->args[i].var);
1322 /* Special local variables */
1323 die_find_child(sc_die, copy_variables_cb, (void *)&vf,
1325 pr_debug(" (%d)\n", vf.nargs - n);
1333 static bool trace_event_finder_overlap(struct trace_event_finder *tf)
1337 for (i = 0; i < tf->ntevs; i++) {
1338 if (tf->pf.addr == tf->tevs[i].point.address)
1344 /* Add a found probe point into trace event list */
1345 static int add_probe_trace_event(Dwarf_Die *sc_die, struct probe_finder *pf)
1347 struct trace_event_finder *tf =
1348 container_of(pf, struct trace_event_finder, pf);
1349 struct perf_probe_point *pp = &pf->pev->point;
1350 struct probe_trace_event *tev;
1351 struct perf_probe_arg *args = NULL;
1355 * For some reason (e.g. different column assigned to same address)
1356 * This callback can be called with the address which already passed.
1359 if (trace_event_finder_overlap(tf))
1362 /* Check number of tevs */
1363 if (tf->ntevs == tf->max_tevs) {
1364 pr_warning("Too many( > %d) probe point found.\n",
1368 tev = &tf->tevs[tf->ntevs++];
1370 /* Trace point should be converted from subprogram DIE */
1371 ret = convert_to_trace_point(&pf->sp_die, tf->mod, pf->addr,
1372 pp->retprobe, pp->function, &tev->point);
1376 tev->point.realname = strdup(dwarf_diename(sc_die));
1377 if (!tev->point.realname) {
1382 pr_debug("Probe point found: %s+%lu\n", tev->point.symbol,
1385 /* Expand special probe argument if exist */
1386 args = zalloc(sizeof(struct perf_probe_arg) * MAX_PROBE_ARGS);
1392 ret = expand_probe_args(sc_die, pf, args);
1397 tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
1398 if (tev->args == NULL) {
1403 /* Find each argument */
1404 for (i = 0; i < tev->nargs; i++) {
1405 pf->pvar = &args[i];
1406 pf->tvar = &tev->args[i];
1407 /* Variable should be found from scope DIE */
1408 ret = find_variable(sc_die, pf);
1415 clear_probe_trace_event(tev);
1422 static int fill_empty_trace_arg(struct perf_probe_event *pev,
1423 struct probe_trace_event *tevs, int ntevs)
1432 for (i = 0; i < pev->nargs; i++) {
1434 for (j = 0; j < ntevs; j++) {
1435 if (tevs[j].args[i].value) {
1436 type = tevs[j].args[i].type;
1441 print_var_not_found(pev->args[i].var);
1444 for (j = 0; j < ntevs; j++) {
1445 valp = &tevs[j].args[i].value;
1449 ret = asprintf(valp, "\\%lx", probe_conf.magic_num);
1452 /* Note that type can be NULL */
1454 tevs[j].args[i].type = strdup(type);
1455 if (!tevs[j].args[i].type)
1463 /* Find probe_trace_events specified by perf_probe_event from debuginfo */
1464 int debuginfo__find_trace_events(struct debuginfo *dbg,
1465 struct perf_probe_event *pev,
1466 struct probe_trace_event **tevs)
1468 struct trace_event_finder tf = {
1469 .pf = {.pev = pev, .dbg = dbg, .callback = add_probe_trace_event},
1470 .max_tevs = probe_conf.max_probes, .mod = dbg->mod};
1473 /* Allocate result tevs array */
1474 *tevs = zalloc(sizeof(struct probe_trace_event) * tf.max_tevs);
1481 if (pev->nargs != 0 && immediate_value_is_supported())
1482 tf.pf.skip_empty_arg = true;
1484 ret = debuginfo__find_probes(dbg, &tf.pf);
1485 if (ret >= 0 && tf.pf.skip_empty_arg)
1486 ret = fill_empty_trace_arg(pev, tf.tevs, tf.ntevs);
1488 if (ret < 0 || tf.ntevs == 0) {
1489 for (i = 0; i < tf.ntevs; i++)
1490 clear_probe_trace_event(&tf.tevs[i]);
1495 return (ret < 0) ? ret : tf.ntevs;
1498 /* Collect available variables in this scope */
1499 static int collect_variables_cb(Dwarf_Die *die_mem, void *data)
1501 struct available_var_finder *af = data;
1502 struct variable_list *vl;
1503 struct strbuf buf = STRBUF_INIT;
1506 vl = &af->vls[af->nvls - 1];
1508 tag = dwarf_tag(die_mem);
1509 if (tag == DW_TAG_formal_parameter ||
1510 tag == DW_TAG_variable) {
1511 ret = convert_variable_location(die_mem, af->pf.addr,
1512 af->pf.fb_ops, &af->pf.sp_die,
1513 af->pf.machine, NULL);
1514 if (ret == 0 || ret == -ERANGE) {
1516 bool externs = !af->child;
1518 if (strbuf_init(&buf, 64) < 0)
1521 if (probe_conf.show_location_range) {
1523 ret2 = strbuf_add(&buf,
1524 ret ? "[INV]\t" : "[VAL]\t", 6);
1526 ret2 = strbuf_add(&buf, "[EXT]\t", 6);
1531 ret2 = die_get_varname(die_mem, &buf);
1533 if (!ret2 && probe_conf.show_location_range &&
1535 if (strbuf_addch(&buf, '\t') < 0)
1537 ret2 = die_get_var_range(&af->pf.sp_die,
1541 pr_debug("Add new var: %s\n", buf.buf);
1543 strlist__add(vl->vars,
1544 strbuf_detach(&buf, NULL));
1546 strbuf_release(&buf);
1550 if (af->child && dwarf_haspc(die_mem, af->pf.addr))
1551 return DIE_FIND_CB_CONTINUE;
1553 return DIE_FIND_CB_SIBLING;
1555 strbuf_release(&buf);
1556 pr_debug("Error in strbuf\n");
1557 return DIE_FIND_CB_END;
1560 static bool available_var_finder_overlap(struct available_var_finder *af)
1564 for (i = 0; i < af->nvls; i++) {
1565 if (af->pf.addr == af->vls[i].point.address)
1572 /* Add a found vars into available variables list */
1573 static int add_available_vars(Dwarf_Die *sc_die, struct probe_finder *pf)
1575 struct available_var_finder *af =
1576 container_of(pf, struct available_var_finder, pf);
1577 struct perf_probe_point *pp = &pf->pev->point;
1578 struct variable_list *vl;
1583 * For some reason (e.g. different column assigned to same address),
1584 * this callback can be called with the address which already passed.
1587 if (available_var_finder_overlap(af))
1590 /* Check number of tevs */
1591 if (af->nvls == af->max_vls) {
1592 pr_warning("Too many( > %d) probe point found.\n", af->max_vls);
1595 vl = &af->vls[af->nvls++];
1597 /* Trace point should be converted from subprogram DIE */
1598 ret = convert_to_trace_point(&pf->sp_die, af->mod, pf->addr,
1599 pp->retprobe, pp->function, &vl->point);
1603 pr_debug("Probe point found: %s+%lu\n", vl->point.symbol,
1606 /* Find local variables */
1607 vl->vars = strlist__new(NULL, NULL);
1608 if (vl->vars == NULL)
1611 die_find_child(sc_die, collect_variables_cb, (void *)af, &die_mem);
1613 /* Find external variables */
1614 if (!probe_conf.show_ext_vars)
1616 /* Don't need to search child DIE for external vars. */
1618 die_find_child(&pf->cu_die, collect_variables_cb, (void *)af, &die_mem);
1621 if (strlist__empty(vl->vars)) {
1622 strlist__delete(vl->vars);
1630 * Find available variables at given probe point
1631 * Return the number of found probe points. Return 0 if there is no
1632 * matched probe point. Return <0 if an error occurs.
1634 int debuginfo__find_available_vars_at(struct debuginfo *dbg,
1635 struct perf_probe_event *pev,
1636 struct variable_list **vls)
1638 struct available_var_finder af = {
1639 .pf = {.pev = pev, .dbg = dbg, .callback = add_available_vars},
1641 .max_vls = probe_conf.max_probes};
1644 /* Allocate result vls array */
1645 *vls = zalloc(sizeof(struct variable_list) * af.max_vls);
1652 ret = debuginfo__find_probes(dbg, &af.pf);
1654 /* Free vlist for error */
1656 zfree(&af.vls[af.nvls].point.symbol);
1657 strlist__delete(af.vls[af.nvls].vars);
1663 return (ret < 0) ? ret : af.nvls;
1666 /* For the kernel module, we need a special code to get a DIE */
1667 int debuginfo__get_text_offset(struct debuginfo *dbg, Dwarf_Addr *offs,
1674 GElf_Shdr mem, *shdr;
1677 elf = dwfl_module_getelf(dbg->mod, &dbg->bias);
1681 /* Get the number of relocations */
1682 n = dwfl_module_relocations(dbg->mod);
1685 /* Search the relocation related .text section */
1686 for (i = 0; i < n; i++) {
1687 p = dwfl_module_relocation_info(dbg->mod, i, &shndx);
1688 if (strcmp(p, ".text") == 0) {
1689 /* OK, get the section header */
1690 scn = elf_getscn(elf, shndx);
1693 shdr = gelf_getshdr(scn, &mem);
1696 *offs = shdr->sh_addr;
1698 *offs -= shdr->sh_offset;
1704 /* Reverse search */
1705 int debuginfo__find_probe_point(struct debuginfo *dbg, unsigned long addr,
1706 struct perf_probe_point *ppt)
1708 Dwarf_Die cudie, spdie, indie;
1709 Dwarf_Addr _addr = 0, baseaddr = 0;
1710 const char *fname = NULL, *func = NULL, *basefunc = NULL, *tmp;
1711 int baseline = 0, lineno = 0, ret = 0;
1713 /* We always need to relocate the address for aranges */
1714 if (debuginfo__get_text_offset(dbg, &baseaddr, false) == 0)
1717 if (!dwarf_addrdie(dbg->dbg, (Dwarf_Addr)addr, &cudie)) {
1718 pr_warning("Failed to find debug information for address %lx\n",
1724 /* Find a corresponding line (filename and lineno) */
1725 cu_find_lineinfo(&cudie, addr, &fname, &lineno);
1726 /* Don't care whether it failed or not */
1728 /* Find a corresponding function (name, baseline and baseaddr) */
1729 if (die_find_realfunc(&cudie, (Dwarf_Addr)addr, &spdie)) {
1730 /* Get function entry information */
1731 func = basefunc = dwarf_diename(&spdie);
1733 die_entrypc(&spdie, &baseaddr) != 0 ||
1734 dwarf_decl_line(&spdie, &baseline) != 0) {
1739 fname = dwarf_decl_file(&spdie);
1740 if (addr == (unsigned long)baseaddr) {
1741 /* Function entry - Relative line number is 0 */
1746 /* Track down the inline functions step by step */
1747 while (die_find_top_inlinefunc(&spdie, (Dwarf_Addr)addr,
1749 /* There is an inline function */
1750 if (die_entrypc(&indie, &_addr) == 0 &&
1753 * addr is at an inline function entry.
1754 * In this case, lineno should be the call-site
1755 * line number. (overwrite lineinfo)
1757 lineno = die_get_call_lineno(&indie);
1758 fname = die_get_call_file(&indie);
1762 * addr is in an inline function body.
1763 * Since lineno points one of the lines
1764 * of the inline function, baseline should
1765 * be the entry line of the inline function.
1767 tmp = dwarf_diename(&indie);
1769 dwarf_decl_line(&indie, &baseline) != 0)
1775 /* Verify the lineno and baseline are in a same file */
1776 tmp = dwarf_decl_file(&spdie);
1777 if (!tmp || strcmp(tmp, fname) != 0)
1782 /* Make a relative line number or an offset */
1784 ppt->line = lineno - baseline;
1785 else if (basefunc) {
1786 ppt->offset = addr - (unsigned long)baseaddr;
1790 /* Duplicate strings */
1792 ppt->function = strdup(func);
1793 if (ppt->function == NULL) {
1799 ppt->file = strdup(fname);
1800 if (ppt->file == NULL) {
1801 zfree(&ppt->function);
1807 if (ret == 0 && (fname || func))
1808 ret = 1; /* Found a point */
1812 /* Add a line and store the src path */
1813 static int line_range_add_line(const char *src, unsigned int lineno,
1814 struct line_range *lr)
1816 /* Copy source path */
1818 lr->path = strdup(src);
1819 if (lr->path == NULL)
1822 return intlist__add(lr->line_list, lineno);
1825 static int line_range_walk_cb(const char *fname, int lineno,
1826 Dwarf_Addr addr __maybe_unused,
1829 struct line_finder *lf = data;
1830 const char *__fname;
1834 if ((strtailcmp(fname, lf->fname) != 0) ||
1835 (lf->lno_s > lineno || lf->lno_e < lineno))
1838 /* Make sure this line can be reversible */
1839 if (cu_find_lineinfo(&lf->cu_die, addr, &__fname, &__lineno) > 0
1840 && (lineno != __lineno || strcmp(fname, __fname)))
1843 err = line_range_add_line(fname, lineno, lf->lr);
1844 if (err < 0 && err != -EEXIST)
1850 /* Find line range from its line number */
1851 static int find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf)
1855 ret = die_walk_lines(sp_die ?: &lf->cu_die, line_range_walk_cb, lf);
1859 if (!intlist__empty(lf->lr->line_list))
1860 ret = lf->found = 1;
1862 ret = 0; /* Lines are not found */
1864 zfree(&lf->lr->path);
1869 static int line_range_inline_cb(Dwarf_Die *in_die, void *data)
1871 int ret = find_line_range_by_line(in_die, data);
1874 * We have to check all instances of inlined function, because
1875 * some execution paths can be optimized out depends on the
1876 * function argument of instances. However, if an error occurs,
1877 * it should be handled by the caller.
1879 return ret < 0 ? ret : 0;
1882 /* Search function definition from function name */
1883 static int line_range_search_cb(Dwarf_Die *sp_die, void *data)
1885 struct dwarf_callback_param *param = data;
1886 struct line_finder *lf = param->data;
1887 struct line_range *lr = lf->lr;
1889 /* Check declared file */
1890 if (lr->file && strtailcmp(lr->file, dwarf_decl_file(sp_die)))
1893 if (die_match_name(sp_die, lr->function) && die_is_func_def(sp_die)) {
1894 lf->fname = dwarf_decl_file(sp_die);
1895 dwarf_decl_line(sp_die, &lr->offset);
1896 pr_debug("fname: %s, lineno:%d\n", lf->fname, lr->offset);
1897 lf->lno_s = lr->offset + lr->start;
1898 if (lf->lno_s < 0) /* Overflow */
1899 lf->lno_s = INT_MAX;
1900 lf->lno_e = lr->offset + lr->end;
1901 if (lf->lno_e < 0) /* Overflow */
1902 lf->lno_e = INT_MAX;
1903 pr_debug("New line range: %d to %d\n", lf->lno_s, lf->lno_e);
1904 lr->start = lf->lno_s;
1905 lr->end = lf->lno_e;
1906 if (!die_is_func_instance(sp_die))
1907 param->retval = die_walk_instances(sp_die,
1908 line_range_inline_cb, lf);
1910 param->retval = find_line_range_by_line(sp_die, lf);
1911 return DWARF_CB_ABORT;
1916 static int find_line_range_by_func(struct line_finder *lf)
1918 struct dwarf_callback_param param = {.data = (void *)lf, .retval = 0};
1919 dwarf_getfuncs(&lf->cu_die, line_range_search_cb, ¶m, 0);
1920 return param.retval;
1923 int debuginfo__find_line_range(struct debuginfo *dbg, struct line_range *lr)
1925 struct line_finder lf = {.lr = lr, .found = 0};
1927 Dwarf_Off off = 0, noff;
1930 const char *comp_dir;
1932 /* Fastpath: lookup by function name from .debug_pubnames section */
1934 struct pubname_callback_param pubname_param = {
1935 .function = lr->function, .file = lr->file,
1936 .cu_die = &lf.cu_die, .sp_die = &lf.sp_die, .found = 0};
1937 struct dwarf_callback_param line_range_param = {
1938 .data = (void *)&lf, .retval = 0};
1940 dwarf_getpubnames(dbg->dbg, pubname_search_cb,
1942 if (pubname_param.found) {
1943 line_range_search_cb(&lf.sp_die, &line_range_param);
1949 /* Loop on CUs (Compilation Unit) */
1950 while (!lf.found && ret >= 0) {
1951 if (dwarf_nextcu(dbg->dbg, off, &noff, &cuhl,
1952 NULL, NULL, NULL) != 0)
1955 /* Get the DIE(Debugging Information Entry) of this CU */
1956 diep = dwarf_offdie(dbg->dbg, off + cuhl, &lf.cu_die);
1962 /* Check if target file is included. */
1964 lf.fname = cu_find_realpath(&lf.cu_die, lr->file);
1968 if (!lr->file || lf.fname) {
1970 ret = find_line_range_by_func(&lf);
1972 lf.lno_s = lr->start;
1974 ret = find_line_range_by_line(NULL, &lf);
1981 /* Store comp_dir */
1983 comp_dir = cu_get_comp_dir(&lf.cu_die);
1985 lr->comp_dir = strdup(comp_dir);
1991 pr_debug("path: %s\n", lr->path);
1992 return (ret < 0) ? ret : lf.found;
1995 #ifdef HAVE_DEBUGINFOD_SUPPORT
1996 /* debuginfod doesn't require the comp_dir but buildid is required */
1997 static int get_source_from_debuginfod(const char *raw_path,
1998 const char *sbuild_id, char **new_path)
2000 debuginfod_client *c = debuginfod_begin();
2001 const char *p = raw_path;
2007 fd = debuginfod_find_source(c, (const unsigned char *)sbuild_id,
2009 pr_debug("Search %s from debuginfod -> %d\n", p, fd);
2014 pr_debug("Failed to find %s in debuginfod (%s)\n",
2015 raw_path, sbuild_id);
2018 pr_debug("Got a source %s\n", *new_path);
2023 static inline int get_source_from_debuginfod(const char *raw_path __maybe_unused,
2024 const char *sbuild_id __maybe_unused,
2025 char **new_path __maybe_unused)
2031 * Find a src file from a DWARF tag path. Prepend optional source path prefix
2032 * and chop off leading directories that do not exist. Result is passed back as
2033 * a newly allocated path on success.
2034 * Return 0 if file was found and readable, -errno otherwise.
2036 int find_source_path(const char *raw_path, const char *sbuild_id,
2037 const char *comp_dir, char **new_path)
2039 const char *prefix = symbol_conf.source_prefix;
2041 if (sbuild_id && !prefix) {
2042 if (!get_source_from_debuginfod(raw_path, sbuild_id, new_path))
2047 if (raw_path[0] != '/' && comp_dir)
2048 /* If not an absolute path, try to use comp_dir */
2051 if (access(raw_path, R_OK) == 0) {
2052 *new_path = strdup(raw_path);
2053 return *new_path ? 0 : -ENOMEM;
2059 *new_path = malloc((strlen(prefix) + strlen(raw_path) + 2));
2064 sprintf(*new_path, "%s/%s", prefix, raw_path);
2066 if (access(*new_path, R_OK) == 0)
2069 if (!symbol_conf.source_prefix) {
2070 /* In case of searching comp_dir, don't retry */
2080 raw_path = strchr(++raw_path, '/');