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;
123 /* Try to open distro debuginfo files */
124 dso = dso__new(path);
128 /* Set the build id for DSO_BINARY_TYPE__BUILDID_DEBUGINFO */
129 if (is_regular_file(path) && filename__read_build_id(path, &bid) > 0)
130 dso__set_build_id(dso, &bid);
132 for (type = distro_dwarf_types;
133 !dinfo && *type != DSO_BINARY_TYPE__NOT_FOUND;
135 if (dso__read_binary_type_filename(dso, *type, &nil,
138 dinfo = __debuginfo__new(buf);
143 /* if failed to open all distro debuginfo, open given binary */
144 return dinfo ? : __debuginfo__new(path);
147 void debuginfo__delete(struct debuginfo *dbg)
157 * Probe finder related functions
160 static struct probe_trace_arg_ref *alloc_trace_arg_ref(long offs)
162 struct probe_trace_arg_ref *ref;
163 ref = zalloc(sizeof(struct probe_trace_arg_ref));
170 * Convert a location into trace_arg.
171 * If tvar == NULL, this just checks variable can be converted.
172 * If fentry == true and vr_die is a parameter, do heuristic search
173 * for the location fuzzed by function entry mcount.
175 static int convert_variable_location(Dwarf_Die *vr_die, Dwarf_Addr addr,
176 Dwarf_Op *fb_ops, Dwarf_Die *sp_die,
177 unsigned int machine,
178 struct probe_trace_arg *tvar)
180 Dwarf_Attribute attr;
190 if (dwarf_attr(vr_die, DW_AT_external, &attr) != NULL)
194 if (dwarf_attr(vr_die, DW_AT_const_value, &attr) &&
195 immediate_value_is_supported()) {
201 dwarf_formsdata(&attr, &snum);
202 ret = asprintf(&tvar->value, "\\%ld", (long)snum);
204 return ret < 0 ? -ENOMEM : 0;
207 /* TODO: handle more than 1 exprs */
208 if (dwarf_attr(vr_die, DW_AT_location, &attr) == NULL)
209 return -EINVAL; /* Broken DIE ? */
210 if (dwarf_getlocation_addr(&attr, addr, &op, &nops, 1) <= 0) {
211 ret = dwarf_entrypc(sp_die, &tmp);
215 if (probe_conf.show_location_range &&
216 (dwarf_tag(vr_die) == DW_TAG_variable)) {
218 } else if (addr != tmp ||
219 dwarf_tag(vr_die) != DW_TAG_formal_parameter) {
223 ret = dwarf_highpc(sp_die, &tmp);
227 * This is fuzzed by fentry mcount. We try to find the
228 * parameter location at the earliest address.
230 for (addr += 1; addr <= tmp; addr++) {
231 if (dwarf_getlocation_addr(&attr, addr, &op,
239 /* TODO: Support const_value */
242 if (op->atom == DW_OP_addr) {
246 /* Static variables on memory (not stack), make @varname */
247 ret = strlen(dwarf_diename(vr_die));
248 tvar->value = zalloc(ret + 2);
249 if (tvar->value == NULL)
251 snprintf(tvar->value, ret + 2, "@%s", dwarf_diename(vr_die));
252 tvar->ref = alloc_trace_arg_ref((long)offs);
253 if (tvar->ref == NULL)
258 /* If this is based on frame buffer, set the offset */
259 if (op->atom == DW_OP_fbreg) {
267 if (op->atom >= DW_OP_breg0 && op->atom <= DW_OP_breg31) {
268 regn = op->atom - DW_OP_breg0;
271 } else if (op->atom >= DW_OP_reg0 && op->atom <= DW_OP_reg31) {
272 regn = op->atom - DW_OP_reg0;
273 } else if (op->atom == DW_OP_bregx) {
277 } else if (op->atom == DW_OP_regx) {
280 pr_debug("DW_OP %x is not supported.\n", op->atom);
287 regs = get_dwarf_regstr(regn, machine);
289 /* This should be a bug in DWARF or this tool */
290 pr_warning("Mapping for the register number %u "
291 "missing on this architecture.\n", regn);
295 tvar->value = strdup(regs);
296 if (tvar->value == NULL)
300 tvar->ref = alloc_trace_arg_ref((long)offs);
301 if (tvar->ref == NULL)
307 #define BYTES_TO_BITS(nb) ((nb) * BITS_PER_LONG / sizeof(long))
309 static int convert_variable_type(Dwarf_Die *vr_die,
310 struct probe_trace_arg *tvar,
311 const char *cast, bool user_access)
313 struct probe_trace_arg_ref **ref_ptr = &tvar->ref;
316 char sbuf[STRERR_BUFSIZE];
317 int bsize, boffs, total;
321 /* TODO: check all types */
322 if (cast && strcmp(cast, "string") != 0 && strcmp(cast, "ustring") &&
323 strcmp(cast, "x") != 0 &&
324 strcmp(cast, "s") != 0 && strcmp(cast, "u") != 0) {
325 /* Non string type is OK */
326 /* and respect signedness/hexadecimal cast */
327 tvar->type = strdup(cast);
328 return (tvar->type == NULL) ? -ENOMEM : 0;
331 bsize = dwarf_bitsize(vr_die);
333 /* This is a bitfield */
334 boffs = dwarf_bitoffset(vr_die);
335 total = dwarf_bytesize(vr_die);
336 if (boffs < 0 || total < 0)
338 ret = snprintf(buf, 16, "b%d@%d/%zd", bsize, boffs,
339 BYTES_TO_BITS(total));
343 if (die_get_real_type(vr_die, &type) == NULL) {
344 pr_warning("Failed to get a type information of %s.\n",
345 dwarf_diename(vr_die));
349 pr_debug("%s type is %s.\n",
350 dwarf_diename(vr_die), dwarf_diename(&type));
352 if (cast && (!strcmp(cast, "string") || !strcmp(cast, "ustring"))) {
354 ret = dwarf_tag(&type);
355 if (ret != DW_TAG_pointer_type &&
356 ret != DW_TAG_array_type) {
357 pr_warning("Failed to cast into string: "
358 "%s(%s) is not a pointer nor array.\n",
359 dwarf_diename(vr_die), dwarf_diename(&type));
362 if (die_get_real_type(&type, &type) == NULL) {
363 pr_warning("Failed to get a type"
367 if (ret == DW_TAG_pointer_type) {
369 ref_ptr = &(*ref_ptr)->next;
370 /* Add new reference with offset +0 */
371 *ref_ptr = zalloc(sizeof(struct probe_trace_arg_ref));
372 if (*ref_ptr == NULL) {
373 pr_warning("Out of memory error\n");
376 (*ref_ptr)->user_access = user_access;
378 if (!die_compare_name(&type, "char") &&
379 !die_compare_name(&type, "unsigned char")) {
380 pr_warning("Failed to cast into string: "
381 "%s is not (unsigned) char *.\n",
382 dwarf_diename(vr_die));
385 tvar->type = strdup(cast);
386 return (tvar->type == NULL) ? -ENOMEM : 0;
389 if (cast && (strcmp(cast, "u") == 0))
391 else if (cast && (strcmp(cast, "s") == 0))
393 else if (cast && (strcmp(cast, "x") == 0) &&
394 probe_type_is_available(PROBE_TYPE_X))
397 prefix = die_is_signed_type(&type) ? 's' :
398 probe_type_is_available(PROBE_TYPE_X) ? 'x' : 'u';
400 ret = dwarf_bytesize(&type);
402 /* No size ... try to use default type */
404 ret = BYTES_TO_BITS(ret);
406 /* Check the bitwidth */
407 if (ret > MAX_BASIC_TYPE_BITS) {
408 pr_info("%s exceeds max-bitwidth. Cut down to %d bits.\n",
409 dwarf_diename(&type), MAX_BASIC_TYPE_BITS);
410 ret = MAX_BASIC_TYPE_BITS;
412 ret = snprintf(buf, 16, "%c%d", prefix, ret);
415 if (ret < 0 || ret >= 16) {
418 pr_warning("Failed to convert variable type: %s\n",
419 str_error_r(-ret, sbuf, sizeof(sbuf)));
422 tvar->type = strdup(buf);
423 if (tvar->type == NULL)
428 static int convert_variable_fields(Dwarf_Die *vr_die, const char *varname,
429 struct perf_probe_arg_field *field,
430 struct probe_trace_arg_ref **ref_ptr,
431 Dwarf_Die *die_mem, bool user_access)
433 struct probe_trace_arg_ref *ref = *ref_ptr;
438 pr_debug("converting %s in %s\n", field->name, varname);
439 if (die_get_real_type(vr_die, &type) == NULL) {
440 pr_warning("Failed to get the type of %s.\n", varname);
443 pr_debug2("Var real type: %s (%x)\n", dwarf_diename(&type),
444 (unsigned)dwarf_dieoffset(&type));
445 tag = dwarf_tag(&type);
447 if (field->name[0] == '[' &&
448 (tag == DW_TAG_array_type || tag == DW_TAG_pointer_type)) {
449 /* Save original type for next field or type */
450 memcpy(die_mem, &type, sizeof(*die_mem));
451 /* Get the type of this array */
452 if (die_get_real_type(&type, &type) == NULL) {
453 pr_warning("Failed to get the type of %s.\n", varname);
456 pr_debug2("Array real type: %s (%x)\n", dwarf_diename(&type),
457 (unsigned)dwarf_dieoffset(&type));
458 if (tag == DW_TAG_pointer_type) {
459 ref = zalloc(sizeof(struct probe_trace_arg_ref));
463 (*ref_ptr)->next = ref;
467 ref->offset += dwarf_bytesize(&type) * field->index;
468 ref->user_access = user_access;
470 } else if (tag == DW_TAG_pointer_type) {
471 /* Check the pointer and dereference */
473 pr_err("Semantic error: %s must be referred by '->'\n",
477 /* Get the type pointed by this pointer */
478 if (die_get_real_type(&type, &type) == NULL) {
479 pr_warning("Failed to get the type of %s.\n", varname);
482 /* Verify it is a data structure */
483 tag = dwarf_tag(&type);
484 if (tag != DW_TAG_structure_type && tag != DW_TAG_union_type) {
485 pr_warning("%s is not a data structure nor a union.\n",
490 ref = zalloc(sizeof(struct probe_trace_arg_ref));
494 (*ref_ptr)->next = ref;
498 /* Verify it is a data structure */
499 if (tag != DW_TAG_structure_type && tag != DW_TAG_union_type) {
500 pr_warning("%s is not a data structure nor a union.\n",
504 if (field->name[0] == '[') {
505 pr_err("Semantic error: %s is not a pointer"
506 " nor array.\n", varname);
509 /* While processing unnamed field, we don't care about this */
510 if (field->ref && dwarf_diename(vr_die)) {
511 pr_err("Semantic error: %s must be referred by '.'\n",
516 pr_warning("Structure on a register is not "
522 if (die_find_member(&type, field->name, die_mem) == NULL) {
523 pr_warning("%s(type:%s) has no member %s.\n", varname,
524 dwarf_diename(&type), field->name);
528 /* Get the offset of the field */
529 if (tag == DW_TAG_union_type) {
532 ret = die_get_data_member_location(die_mem, &offs);
534 pr_warning("Failed to get the offset of %s.\n",
539 ref->offset += (long)offs;
540 ref->user_access = user_access;
542 /* If this member is unnamed, we need to reuse this field */
543 if (!dwarf_diename(die_mem))
544 return convert_variable_fields(die_mem, varname, field,
545 &ref, die_mem, user_access);
548 /* Converting next field */
550 return convert_variable_fields(die_mem, field->name,
551 field->next, &ref, die_mem, user_access);
556 static void print_var_not_found(const char *varname)
558 pr_err("Failed to find the location of the '%s' variable at this address.\n"
559 " Perhaps it has been optimized out.\n"
560 " Use -V with the --range option to show '%s' location range.\n",
564 /* Show a variables in kprobe event format */
565 static int convert_variable(Dwarf_Die *vr_die, struct probe_finder *pf)
570 pr_debug("Converting variable %s into trace event.\n",
571 dwarf_diename(vr_die));
573 ret = convert_variable_location(vr_die, pf->addr, pf->fb_ops,
574 &pf->sp_die, pf->machine, pf->tvar);
575 if (ret == -ENOENT && pf->skip_empty_arg)
576 /* This can be found in other place. skip it */
578 if (ret == -ENOENT || ret == -EINVAL) {
579 print_var_not_found(pf->pvar->var);
580 } else if (ret == -ENOTSUP)
581 pr_err("Sorry, we don't support this variable location yet.\n");
582 else if (ret == 0 && pf->pvar->field) {
583 ret = convert_variable_fields(vr_die, pf->pvar->var,
584 pf->pvar->field, &pf->tvar->ref,
585 &die_mem, pf->pvar->user_access);
589 ret = convert_variable_type(vr_die, pf->tvar, pf->pvar->type,
590 pf->pvar->user_access);
591 /* *expr will be cached in libdw. Don't free it. */
595 /* Find a variable in a scope DIE */
596 static int find_variable(Dwarf_Die *sc_die, struct probe_finder *pf)
602 /* Copy raw parameters */
603 if (!is_c_varname(pf->pvar->var))
604 return copy_to_probe_trace_arg(pf->tvar, pf->pvar);
607 pf->tvar->name = strdup(pf->pvar->name);
609 buf = synthesize_perf_probe_arg(pf->pvar);
612 ptr = strchr(buf, ':'); /* Change type separator to _ */
615 pf->tvar->name = buf;
617 if (pf->tvar->name == NULL)
620 pr_debug("Searching '%s' variable in context.\n", pf->pvar->var);
621 /* Search child die for local variables and parameters. */
622 if (!die_find_variable_at(sc_die, pf->pvar->var, pf->addr, &vr_die)) {
623 /* Search again in global variables */
624 if (!die_find_variable_at(&pf->cu_die, pf->pvar->var,
626 if (pf->skip_empty_arg)
628 pr_warning("Failed to find '%s' in this function.\n",
634 ret = convert_variable(&vr_die, pf);
639 /* Convert subprogram DIE to trace point */
640 static int convert_to_trace_point(Dwarf_Die *sp_die, Dwfl_Module *mod,
641 Dwarf_Addr paddr, bool retprobe,
642 const char *function,
643 struct probe_trace_point *tp)
649 /* Verify the address is correct */
650 if (!dwarf_haspc(sp_die, paddr)) {
651 pr_warning("Specified offset is out of %s\n",
652 dwarf_diename(sp_die));
656 if (dwarf_entrypc(sp_die, &eaddr) == 0) {
657 /* If the DIE has entrypc, use it. */
658 symbol = dwarf_diename(sp_die);
660 /* Try to get actual symbol name and address from symtab */
661 symbol = dwfl_module_addrsym(mod, paddr, &sym, NULL);
662 eaddr = sym.st_value;
665 pr_warning("Failed to find symbol at 0x%lx\n",
666 (unsigned long)paddr);
670 tp->offset = (unsigned long)(paddr - eaddr);
672 tp->symbol = strdup(symbol);
676 /* Return probe must be on the head of a subprogram */
678 if (eaddr != paddr) {
679 pr_warning("Failed to find \"%s%%return\",\n"
680 " because %s is an inlined function and"
681 " has no return point.\n", function,
691 /* Call probe_finder callback with scope DIE */
692 static int call_probe_finder(Dwarf_Die *sc_die, struct probe_finder *pf)
694 Dwarf_Attribute fb_attr;
695 Dwarf_Frame *frame = NULL;
700 pr_err("Caller must pass a scope DIE. Program error.\n");
704 /* If not a real subprogram, find a real one */
705 if (!die_is_func_def(sc_die)) {
706 if (!die_find_realfunc(&pf->cu_die, pf->addr, &pf->sp_die)) {
707 if (die_find_tailfunc(&pf->cu_die, pf->addr, &pf->sp_die)) {
708 pr_warning("Ignoring tail call from %s\n",
709 dwarf_diename(&pf->sp_die));
712 pr_warning("Failed to find probe point in any "
718 memcpy(&pf->sp_die, sc_die, sizeof(Dwarf_Die));
720 /* Get the frame base attribute/ops from subprogram */
721 dwarf_attr(&pf->sp_die, DW_AT_frame_base, &fb_attr);
722 ret = dwarf_getlocation_addr(&fb_attr, pf->addr, &pf->fb_ops, &nops, 1);
723 if (ret <= 0 || nops == 0) {
725 #if _ELFUTILS_PREREQ(0, 142)
726 } else if (nops == 1 && pf->fb_ops[0].atom == DW_OP_call_frame_cfa &&
727 (pf->cfi_eh != NULL || pf->cfi_dbg != NULL)) {
728 if ((dwarf_cfi_addrframe(pf->cfi_eh, pf->addr, &frame) != 0 &&
729 (dwarf_cfi_addrframe(pf->cfi_dbg, pf->addr, &frame) != 0)) ||
730 dwarf_frame_cfa(frame, &pf->fb_ops, &nops) != 0) {
731 pr_warning("Failed to get call frame on 0x%jx\n",
732 (uintmax_t)pf->addr);
739 /* Call finder's callback handler */
740 ret = pf->callback(sc_die, pf);
742 /* Since *pf->fb_ops can be a part of frame. we should free it here. */
749 struct find_scope_param {
750 const char *function;
758 static int find_best_scope_cb(Dwarf_Die *fn_die, void *data)
760 struct find_scope_param *fsp = data;
764 /* Skip if declared file name does not match */
766 file = dwarf_decl_file(fn_die);
767 if (!file || strcmp(fsp->file, file) != 0)
770 /* If the function name is given, that's what user expects */
772 if (die_match_name(fn_die, fsp->function)) {
773 memcpy(fsp->die_mem, fn_die, sizeof(Dwarf_Die));
778 /* With the line number, find the nearest declared DIE */
779 dwarf_decl_line(fn_die, &lno);
780 if (lno < fsp->line && fsp->diff > fsp->line - lno) {
781 /* Keep a candidate and continue */
782 fsp->diff = fsp->line - lno;
783 memcpy(fsp->die_mem, fn_die, sizeof(Dwarf_Die));
790 /* Return innermost DIE */
791 static int find_inner_scope_cb(Dwarf_Die *fn_die, void *data)
793 struct find_scope_param *fsp = data;
795 memcpy(fsp->die_mem, fn_die, sizeof(Dwarf_Die));
800 /* Find an appropriate scope fits to given conditions */
801 static Dwarf_Die *find_best_scope(struct probe_finder *pf, Dwarf_Die *die_mem)
803 struct find_scope_param fsp = {
804 .function = pf->pev->point.function,
813 ret = cu_walk_functions_at(&pf->cu_die, pf->addr, find_best_scope_cb,
815 if (!ret && !fsp.found)
816 cu_walk_functions_at(&pf->cu_die, pf->addr,
817 find_inner_scope_cb, &fsp);
819 return fsp.found ? die_mem : NULL;
822 static int verify_representive_line(struct probe_finder *pf, const char *fname,
823 int lineno, Dwarf_Addr addr)
825 const char *__fname, *__func = NULL;
829 /* Verify line number and address by reverse search */
830 if (cu_find_lineinfo(&pf->cu_die, addr, &__fname, &__lineno) < 0)
833 pr_debug2("Reversed line: %s:%d\n", __fname, __lineno);
834 if (strcmp(fname, __fname) || lineno == __lineno)
837 pr_warning("This line is sharing the address with other lines.\n");
839 if (pf->pev->point.function) {
840 /* Find best match function name and lines */
842 if (find_best_scope(pf, &die_mem)
843 && die_match_name(&die_mem, pf->pev->point.function)
844 && dwarf_decl_line(&die_mem, &lineno) == 0) {
845 __func = dwarf_diename(&die_mem);
849 pr_warning("Please try to probe at %s:%d instead.\n",
850 __func ? : __fname, __lineno);
855 static int probe_point_line_walker(const char *fname, int lineno,
856 Dwarf_Addr addr, void *data)
858 struct probe_finder *pf = data;
859 Dwarf_Die *sc_die, die_mem;
862 if (lineno != pf->lno || strtailcmp(fname, pf->fname) != 0)
865 if (verify_representive_line(pf, fname, lineno, addr))
869 sc_die = find_best_scope(pf, &die_mem);
871 pr_warning("Failed to find scope of probe point.\n");
875 ret = call_probe_finder(sc_die, pf);
877 /* Continue if no error, because the line will be in inline function */
878 return ret < 0 ? ret : 0;
881 /* Find probe point from its line number */
882 static int find_probe_point_by_line(struct probe_finder *pf)
884 return die_walk_lines(&pf->cu_die, probe_point_line_walker, pf);
887 /* Find lines which match lazy pattern */
888 static int find_lazy_match_lines(struct intlist *list,
889 const char *fname, const char *pat)
895 int count = 0, linenum = 1;
896 char sbuf[STRERR_BUFSIZE];
898 fp = fopen(fname, "r");
900 pr_warning("Failed to open %s: %s\n", fname,
901 str_error_r(errno, sbuf, sizeof(sbuf)));
905 while ((len = getline(&line, &line_len, fp)) > 0) {
907 if (line[len - 1] == '\n')
908 line[len - 1] = '\0';
910 if (strlazymatch(line, pat)) {
911 intlist__add(list, linenum);
923 pr_debug("No matched lines found in %s.\n", fname);
927 static int probe_point_lazy_walker(const char *fname, int lineno,
928 Dwarf_Addr addr, void *data)
930 struct probe_finder *pf = data;
931 Dwarf_Die *sc_die, die_mem;
934 if (!intlist__has_entry(pf->lcache, lineno) ||
935 strtailcmp(fname, pf->fname) != 0)
938 pr_debug("Probe line found: line:%d addr:0x%llx\n",
939 lineno, (unsigned long long)addr);
942 sc_die = find_best_scope(pf, &die_mem);
944 pr_warning("Failed to find scope of probe point.\n");
948 ret = call_probe_finder(sc_die, pf);
951 * Continue if no error, because the lazy pattern will match
954 return ret < 0 ? ret : 0;
957 /* Find probe points from lazy pattern */
958 static int find_probe_point_lazy(Dwarf_Die *sp_die, struct probe_finder *pf)
961 char sbuild_id[SBUILD_ID_SIZE] = "";
965 if (intlist__empty(pf->lcache)) {
966 const char *comp_dir;
968 comp_dir = cu_get_comp_dir(&pf->cu_die);
969 if (pf->dbg->build_id) {
970 build_id__init(&bid, pf->dbg->build_id, BUILD_ID_SIZE);
971 build_id__sprintf(&bid, sbuild_id);
973 ret = find_source_path(pf->fname, sbuild_id, comp_dir, &fpath);
975 pr_warning("Failed to find source file path.\n");
979 /* Matching lazy line pattern */
980 ret = find_lazy_match_lines(pf->lcache, fpath,
981 pf->pev->point.lazy_line);
987 return die_walk_lines(sp_die, probe_point_lazy_walker, pf);
990 static void skip_prologue(Dwarf_Die *sp_die, struct probe_finder *pf)
992 struct perf_probe_point *pp = &pf->pev->point;
995 if (!pf->pev->uprobes)
998 /* Compiled with optimization? */
999 if (die_is_optimized_target(&pf->cu_die))
1002 /* Don't know entrypc? */
1006 /* Only FUNC and FUNC@SRC are eligible. */
1007 if (!pp->function || pp->line || pp->retprobe || pp->lazy_line ||
1008 pp->offset || pp->abs_address)
1011 /* Not interested in func parameter? */
1012 if (!perf_probe_with_var(pf->pev))
1015 pr_info("Target program is compiled without optimization. Skipping prologue.\n"
1016 "Probe on address 0x%" PRIx64 " to force probing at the function entry.\n\n",
1019 die_skip_prologue(sp_die, &pf->cu_die, &pf->addr);
1022 static int probe_point_inline_cb(Dwarf_Die *in_die, void *data)
1024 struct probe_finder *pf = data;
1025 struct perf_probe_point *pp = &pf->pev->point;
1030 ret = find_probe_point_lazy(in_die, pf);
1032 /* Get probe address */
1033 if (die_entrypc(in_die, &addr) != 0) {
1034 pr_warning("Failed to get entry address of %s.\n",
1035 dwarf_diename(in_die));
1039 pr_debug("%s has no valid entry address. skipped.\n",
1040 dwarf_diename(in_die));
1044 pf->addr += pp->offset;
1045 pr_debug("found inline addr: 0x%jx\n",
1046 (uintmax_t)pf->addr);
1048 ret = call_probe_finder(in_die, pf);
1054 /* Callback parameter with return value for libdw */
1055 struct dwarf_callback_param {
1060 /* Search function from function name */
1061 static int probe_point_search_cb(Dwarf_Die *sp_die, void *data)
1063 struct dwarf_callback_param *param = data;
1064 struct probe_finder *pf = param->data;
1065 struct perf_probe_point *pp = &pf->pev->point;
1067 /* Check tag and diename */
1068 if (!die_is_func_def(sp_die) ||
1069 !die_match_name(sp_die, pp->function))
1072 /* Check declared file */
1073 if (pp->file && strtailcmp(pp->file, dwarf_decl_file(sp_die)))
1076 pr_debug("Matched function: %s [%lx]\n", dwarf_diename(sp_die),
1077 (unsigned long)dwarf_dieoffset(sp_die));
1078 pf->fname = dwarf_decl_file(sp_die);
1079 if (pp->line) { /* Function relative line */
1080 dwarf_decl_line(sp_die, &pf->lno);
1081 pf->lno += pp->line;
1082 param->retval = find_probe_point_by_line(pf);
1083 } else if (die_is_func_instance(sp_die)) {
1084 /* Instances always have the entry address */
1085 die_entrypc(sp_die, &pf->addr);
1086 /* But in some case the entry address is 0 */
1087 if (pf->addr == 0) {
1088 pr_debug("%s has no entry PC. Skipped\n",
1089 dwarf_diename(sp_die));
1092 } else if (pp->lazy_line)
1093 param->retval = find_probe_point_lazy(sp_die, pf);
1095 skip_prologue(sp_die, pf);
1096 pf->addr += pp->offset;
1097 /* TODO: Check the address in this function */
1098 param->retval = call_probe_finder(sp_die, pf);
1100 } else if (!probe_conf.no_inlines) {
1101 /* Inlined function: search instances */
1102 param->retval = die_walk_instances(sp_die,
1103 probe_point_inline_cb, (void *)pf);
1104 /* This could be a non-existed inline definition */
1105 if (param->retval == -ENOENT)
1109 /* We need to find other candidates */
1110 if (strisglob(pp->function) && param->retval >= 0) {
1111 param->retval = 0; /* We have to clear the result */
1115 return DWARF_CB_ABORT; /* Exit; no same symbol in this CU. */
1118 static int find_probe_point_by_func(struct probe_finder *pf)
1120 struct dwarf_callback_param _param = {.data = (void *)pf,
1122 dwarf_getfuncs(&pf->cu_die, probe_point_search_cb, &_param, 0);
1123 return _param.retval;
1126 struct pubname_callback_param {
1134 static int pubname_search_cb(Dwarf *dbg, Dwarf_Global *gl, void *data)
1136 struct pubname_callback_param *param = data;
1138 if (dwarf_offdie(dbg, gl->die_offset, param->sp_die)) {
1139 if (dwarf_tag(param->sp_die) != DW_TAG_subprogram)
1142 if (die_match_name(param->sp_die, param->function)) {
1143 if (!dwarf_offdie(dbg, gl->cu_offset, param->cu_die))
1147 strtailcmp(param->file, dwarf_decl_file(param->sp_die)))
1151 return DWARF_CB_ABORT;
1158 static int debuginfo__find_probe_location(struct debuginfo *dbg,
1159 struct probe_finder *pf)
1161 struct perf_probe_point *pp = &pf->pev->point;
1162 Dwarf_Off off, noff;
1168 pf->lcache = intlist__new(NULL);
1172 /* Fastpath: lookup by function name from .debug_pubnames section */
1173 if (pp->function && !strisglob(pp->function)) {
1174 struct pubname_callback_param pubname_param = {
1175 .function = pp->function,
1177 .cu_die = &pf->cu_die,
1178 .sp_die = &pf->sp_die,
1181 struct dwarf_callback_param probe_param = {
1185 dwarf_getpubnames(dbg->dbg, pubname_search_cb,
1187 if (pubname_param.found) {
1188 ret = probe_point_search_cb(&pf->sp_die, &probe_param);
1194 /* Loop on CUs (Compilation Unit) */
1195 while (!dwarf_nextcu(dbg->dbg, off, &noff, &cuhl, NULL, NULL, NULL)) {
1196 /* Get the DIE(Debugging Information Entry) of this CU */
1197 diep = dwarf_offdie(dbg->dbg, off + cuhl, &pf->cu_die);
1203 /* Check if target file is included. */
1205 pf->fname = cu_find_realpath(&pf->cu_die, pp->file);
1209 if (!pp->file || pf->fname) {
1211 ret = find_probe_point_by_func(pf);
1212 else if (pp->lazy_line)
1213 ret = find_probe_point_lazy(&pf->cu_die, pf);
1216 ret = find_probe_point_by_line(pf);
1225 intlist__delete(pf->lcache);
1231 /* Find probe points from debuginfo */
1232 static int debuginfo__find_probes(struct debuginfo *dbg,
1233 struct probe_finder *pf)
1239 if (pf->cfi_eh || pf->cfi_dbg)
1240 return debuginfo__find_probe_location(dbg, pf);
1242 /* Get the call frame information from this dwarf */
1243 elf = dwarf_getelf(dbg->dbg);
1247 if (gelf_getehdr(elf, &ehdr) == NULL)
1250 pf->machine = ehdr.e_machine;
1252 #if _ELFUTILS_PREREQ(0, 142)
1256 if (elf_section_by_name(elf, &ehdr, &shdr, ".eh_frame", NULL) &&
1257 shdr.sh_type == SHT_PROGBITS)
1258 pf->cfi_eh = dwarf_getcfi_elf(elf);
1260 pf->cfi_dbg = dwarf_getcfi(dbg->dbg);
1264 ret = debuginfo__find_probe_location(dbg, pf);
1268 struct local_vars_finder {
1269 struct probe_finder *pf;
1270 struct perf_probe_arg *args;
1277 /* Collect available variables in this scope */
1278 static int copy_variables_cb(Dwarf_Die *die_mem, void *data)
1280 struct local_vars_finder *vf = data;
1281 struct probe_finder *pf = vf->pf;
1284 tag = dwarf_tag(die_mem);
1285 if (tag == DW_TAG_formal_parameter ||
1286 (tag == DW_TAG_variable && vf->vars)) {
1287 if (convert_variable_location(die_mem, vf->pf->addr,
1288 vf->pf->fb_ops, &pf->sp_die,
1289 pf->machine, NULL) == 0) {
1290 vf->args[vf->nargs].var = (char *)dwarf_diename(die_mem);
1291 if (vf->args[vf->nargs].var == NULL) {
1293 return DIE_FIND_CB_END;
1295 pr_debug(" %s", vf->args[vf->nargs].var);
1300 if (dwarf_haspc(die_mem, vf->pf->addr))
1301 return DIE_FIND_CB_CONTINUE;
1303 return DIE_FIND_CB_SIBLING;
1306 static int expand_probe_args(Dwarf_Die *sc_die, struct probe_finder *pf,
1307 struct perf_probe_arg *args)
1312 struct local_vars_finder vf = {.pf = pf, .args = args, .vars = false,
1313 .max_args = MAX_PROBE_ARGS, .ret = 0};
1315 for (i = 0; i < pf->pev->nargs; i++) {
1316 /* var never be NULL */
1317 if (strcmp(pf->pev->args[i].var, PROBE_ARG_VARS) == 0)
1319 else if (strcmp(pf->pev->args[i].var, PROBE_ARG_PARAMS) != 0) {
1320 /* Copy normal argument */
1321 args[n] = pf->pev->args[i];
1325 pr_debug("Expanding %s into:", pf->pev->args[i].var);
1327 /* Special local variables */
1328 die_find_child(sc_die, copy_variables_cb, (void *)&vf,
1330 pr_debug(" (%d)\n", vf.nargs - n);
1338 static bool trace_event_finder_overlap(struct trace_event_finder *tf)
1342 for (i = 0; i < tf->ntevs; i++) {
1343 if (tf->pf.addr == tf->tevs[i].point.address)
1349 /* Add a found probe point into trace event list */
1350 static int add_probe_trace_event(Dwarf_Die *sc_die, struct probe_finder *pf)
1352 struct trace_event_finder *tf =
1353 container_of(pf, struct trace_event_finder, pf);
1354 struct perf_probe_point *pp = &pf->pev->point;
1355 struct probe_trace_event *tev;
1356 struct perf_probe_arg *args = NULL;
1360 * For some reason (e.g. different column assigned to same address)
1361 * This callback can be called with the address which already passed.
1364 if (trace_event_finder_overlap(tf))
1367 /* Check number of tevs */
1368 if (tf->ntevs == tf->max_tevs) {
1369 pr_warning("Too many( > %d) probe point found.\n",
1373 tev = &tf->tevs[tf->ntevs++];
1375 /* Trace point should be converted from subprogram DIE */
1376 ret = convert_to_trace_point(&pf->sp_die, tf->mod, pf->addr,
1377 pp->retprobe, pp->function, &tev->point);
1381 tev->point.realname = strdup(dwarf_diename(sc_die));
1382 if (!tev->point.realname) {
1387 pr_debug("Probe point found: %s+%lu\n", tev->point.symbol,
1390 /* Expand special probe argument if exist */
1391 args = zalloc(sizeof(struct perf_probe_arg) * MAX_PROBE_ARGS);
1397 ret = expand_probe_args(sc_die, pf, args);
1402 tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
1403 if (tev->args == NULL) {
1408 /* Find each argument */
1409 for (i = 0; i < tev->nargs; i++) {
1410 pf->pvar = &args[i];
1411 pf->tvar = &tev->args[i];
1412 /* Variable should be found from scope DIE */
1413 ret = find_variable(sc_die, pf);
1420 clear_probe_trace_event(tev);
1427 static int fill_empty_trace_arg(struct perf_probe_event *pev,
1428 struct probe_trace_event *tevs, int ntevs)
1437 for (i = 0; i < pev->nargs; i++) {
1439 for (j = 0; j < ntevs; j++) {
1440 if (tevs[j].args[i].value) {
1441 type = tevs[j].args[i].type;
1446 print_var_not_found(pev->args[i].var);
1449 for (j = 0; j < ntevs; j++) {
1450 valp = &tevs[j].args[i].value;
1454 ret = asprintf(valp, "\\%lx", probe_conf.magic_num);
1457 /* Note that type can be NULL */
1459 tevs[j].args[i].type = strdup(type);
1460 if (!tevs[j].args[i].type)
1468 /* Find probe_trace_events specified by perf_probe_event from debuginfo */
1469 int debuginfo__find_trace_events(struct debuginfo *dbg,
1470 struct perf_probe_event *pev,
1471 struct probe_trace_event **tevs)
1473 struct trace_event_finder tf = {
1474 .pf = {.pev = pev, .dbg = dbg, .callback = add_probe_trace_event},
1475 .max_tevs = probe_conf.max_probes, .mod = dbg->mod};
1478 /* Allocate result tevs array */
1479 *tevs = zalloc(sizeof(struct probe_trace_event) * tf.max_tevs);
1486 if (pev->nargs != 0 && immediate_value_is_supported())
1487 tf.pf.skip_empty_arg = true;
1489 ret = debuginfo__find_probes(dbg, &tf.pf);
1490 if (ret >= 0 && tf.pf.skip_empty_arg)
1491 ret = fill_empty_trace_arg(pev, tf.tevs, tf.ntevs);
1493 if (ret < 0 || tf.ntevs == 0) {
1494 for (i = 0; i < tf.ntevs; i++)
1495 clear_probe_trace_event(&tf.tevs[i]);
1500 return (ret < 0) ? ret : tf.ntevs;
1503 /* Collect available variables in this scope */
1504 static int collect_variables_cb(Dwarf_Die *die_mem, void *data)
1506 struct available_var_finder *af = data;
1507 struct variable_list *vl;
1508 struct strbuf buf = STRBUF_INIT;
1511 vl = &af->vls[af->nvls - 1];
1513 tag = dwarf_tag(die_mem);
1514 if (tag == DW_TAG_formal_parameter ||
1515 tag == DW_TAG_variable) {
1516 ret = convert_variable_location(die_mem, af->pf.addr,
1517 af->pf.fb_ops, &af->pf.sp_die,
1518 af->pf.machine, NULL);
1519 if (ret == 0 || ret == -ERANGE) {
1521 bool externs = !af->child;
1523 if (strbuf_init(&buf, 64) < 0)
1526 if (probe_conf.show_location_range) {
1528 ret2 = strbuf_add(&buf,
1529 ret ? "[INV]\t" : "[VAL]\t", 6);
1531 ret2 = strbuf_add(&buf, "[EXT]\t", 6);
1536 ret2 = die_get_varname(die_mem, &buf);
1538 if (!ret2 && probe_conf.show_location_range &&
1540 if (strbuf_addch(&buf, '\t') < 0)
1542 ret2 = die_get_var_range(&af->pf.sp_die,
1546 pr_debug("Add new var: %s\n", buf.buf);
1548 strlist__add(vl->vars,
1549 strbuf_detach(&buf, NULL));
1551 strbuf_release(&buf);
1555 if (af->child && dwarf_haspc(die_mem, af->pf.addr))
1556 return DIE_FIND_CB_CONTINUE;
1558 return DIE_FIND_CB_SIBLING;
1560 strbuf_release(&buf);
1561 pr_debug("Error in strbuf\n");
1562 return DIE_FIND_CB_END;
1565 static bool available_var_finder_overlap(struct available_var_finder *af)
1569 for (i = 0; i < af->nvls; i++) {
1570 if (af->pf.addr == af->vls[i].point.address)
1577 /* Add a found vars into available variables list */
1578 static int add_available_vars(Dwarf_Die *sc_die, struct probe_finder *pf)
1580 struct available_var_finder *af =
1581 container_of(pf, struct available_var_finder, pf);
1582 struct perf_probe_point *pp = &pf->pev->point;
1583 struct variable_list *vl;
1588 * For some reason (e.g. different column assigned to same address),
1589 * this callback can be called with the address which already passed.
1592 if (available_var_finder_overlap(af))
1595 /* Check number of tevs */
1596 if (af->nvls == af->max_vls) {
1597 pr_warning("Too many( > %d) probe point found.\n", af->max_vls);
1600 vl = &af->vls[af->nvls++];
1602 /* Trace point should be converted from subprogram DIE */
1603 ret = convert_to_trace_point(&pf->sp_die, af->mod, pf->addr,
1604 pp->retprobe, pp->function, &vl->point);
1608 pr_debug("Probe point found: %s+%lu\n", vl->point.symbol,
1611 /* Find local variables */
1612 vl->vars = strlist__new(NULL, NULL);
1613 if (vl->vars == NULL)
1616 die_find_child(sc_die, collect_variables_cb, (void *)af, &die_mem);
1618 /* Find external variables */
1619 if (!probe_conf.show_ext_vars)
1621 /* Don't need to search child DIE for external vars. */
1623 die_find_child(&pf->cu_die, collect_variables_cb, (void *)af, &die_mem);
1626 if (strlist__empty(vl->vars)) {
1627 strlist__delete(vl->vars);
1635 * Find available variables at given probe point
1636 * Return the number of found probe points. Return 0 if there is no
1637 * matched probe point. Return <0 if an error occurs.
1639 int debuginfo__find_available_vars_at(struct debuginfo *dbg,
1640 struct perf_probe_event *pev,
1641 struct variable_list **vls)
1643 struct available_var_finder af = {
1644 .pf = {.pev = pev, .dbg = dbg, .callback = add_available_vars},
1646 .max_vls = probe_conf.max_probes};
1649 /* Allocate result vls array */
1650 *vls = zalloc(sizeof(struct variable_list) * af.max_vls);
1657 ret = debuginfo__find_probes(dbg, &af.pf);
1659 /* Free vlist for error */
1661 zfree(&af.vls[af.nvls].point.symbol);
1662 strlist__delete(af.vls[af.nvls].vars);
1668 return (ret < 0) ? ret : af.nvls;
1671 /* For the kernel module, we need a special code to get a DIE */
1672 int debuginfo__get_text_offset(struct debuginfo *dbg, Dwarf_Addr *offs,
1679 GElf_Shdr mem, *shdr;
1682 elf = dwfl_module_getelf(dbg->mod, &dbg->bias);
1686 /* Get the number of relocations */
1687 n = dwfl_module_relocations(dbg->mod);
1690 /* Search the relocation related .text section */
1691 for (i = 0; i < n; i++) {
1692 p = dwfl_module_relocation_info(dbg->mod, i, &shndx);
1693 if (strcmp(p, ".text") == 0) {
1694 /* OK, get the section header */
1695 scn = elf_getscn(elf, shndx);
1698 shdr = gelf_getshdr(scn, &mem);
1701 *offs = shdr->sh_addr;
1703 *offs -= shdr->sh_offset;
1709 /* Reverse search */
1710 int debuginfo__find_probe_point(struct debuginfo *dbg, u64 addr,
1711 struct perf_probe_point *ppt)
1713 Dwarf_Die cudie, spdie, indie;
1714 Dwarf_Addr _addr = 0, baseaddr = 0;
1715 const char *fname = NULL, *func = NULL, *basefunc = NULL, *tmp;
1716 int baseline = 0, lineno = 0, ret = 0;
1718 /* We always need to relocate the address for aranges */
1719 if (debuginfo__get_text_offset(dbg, &baseaddr, false) == 0)
1722 if (!dwarf_addrdie(dbg->dbg, (Dwarf_Addr)addr, &cudie)) {
1723 pr_warning("Failed to find debug information for address %" PRIx64 "\n",
1729 /* Find a corresponding line (filename and lineno) */
1730 cu_find_lineinfo(&cudie, (Dwarf_Addr)addr, &fname, &lineno);
1731 /* Don't care whether it failed or not */
1733 /* Find a corresponding function (name, baseline and baseaddr) */
1734 if (die_find_realfunc(&cudie, (Dwarf_Addr)addr, &spdie)) {
1735 /* Get function entry information */
1736 func = basefunc = dwarf_diename(&spdie);
1738 die_entrypc(&spdie, &baseaddr) != 0 ||
1739 dwarf_decl_line(&spdie, &baseline) != 0) {
1744 fname = dwarf_decl_file(&spdie);
1745 if (addr == baseaddr) {
1746 /* Function entry - Relative line number is 0 */
1751 /* Track down the inline functions step by step */
1752 while (die_find_top_inlinefunc(&spdie, (Dwarf_Addr)addr,
1754 /* There is an inline function */
1755 if (die_entrypc(&indie, &_addr) == 0 &&
1758 * addr is at an inline function entry.
1759 * In this case, lineno should be the call-site
1760 * line number. (overwrite lineinfo)
1762 lineno = die_get_call_lineno(&indie);
1763 fname = die_get_call_file(&indie);
1767 * addr is in an inline function body.
1768 * Since lineno points one of the lines
1769 * of the inline function, baseline should
1770 * be the entry line of the inline function.
1772 tmp = dwarf_diename(&indie);
1774 dwarf_decl_line(&indie, &baseline) != 0)
1780 /* Verify the lineno and baseline are in a same file */
1781 tmp = dwarf_decl_file(&spdie);
1782 if (!tmp || strcmp(tmp, fname) != 0)
1787 /* Make a relative line number or an offset */
1789 ppt->line = lineno - baseline;
1790 else if (basefunc) {
1791 ppt->offset = addr - baseaddr;
1795 /* Duplicate strings */
1797 ppt->function = strdup(func);
1798 if (ppt->function == NULL) {
1804 ppt->file = strdup(fname);
1805 if (ppt->file == NULL) {
1806 zfree(&ppt->function);
1812 if (ret == 0 && (fname || func))
1813 ret = 1; /* Found a point */
1817 /* Add a line and store the src path */
1818 static int line_range_add_line(const char *src, unsigned int lineno,
1819 struct line_range *lr)
1821 /* Copy source path */
1823 lr->path = strdup(src);
1824 if (lr->path == NULL)
1827 return intlist__add(lr->line_list, lineno);
1830 static int line_range_walk_cb(const char *fname, int lineno,
1831 Dwarf_Addr addr, void *data)
1833 struct line_finder *lf = data;
1834 const char *__fname;
1838 if ((strtailcmp(fname, lf->fname) != 0) ||
1839 (lf->lno_s > lineno || lf->lno_e < lineno))
1842 /* Make sure this line can be reversible */
1843 if (cu_find_lineinfo(&lf->cu_die, addr, &__fname, &__lineno) > 0
1844 && (lineno != __lineno || strcmp(fname, __fname)))
1847 err = line_range_add_line(fname, lineno, lf->lr);
1848 if (err < 0 && err != -EEXIST)
1854 /* Find line range from its line number */
1855 static int find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf)
1859 ret = die_walk_lines(sp_die ?: &lf->cu_die, line_range_walk_cb, lf);
1863 if (!intlist__empty(lf->lr->line_list))
1864 ret = lf->found = 1;
1866 ret = 0; /* Lines are not found */
1868 zfree(&lf->lr->path);
1873 static int line_range_inline_cb(Dwarf_Die *in_die, void *data)
1875 int ret = find_line_range_by_line(in_die, data);
1878 * We have to check all instances of inlined function, because
1879 * some execution paths can be optimized out depends on the
1880 * function argument of instances. However, if an error occurs,
1881 * it should be handled by the caller.
1883 return ret < 0 ? ret : 0;
1886 /* Search function definition from function name */
1887 static int line_range_search_cb(Dwarf_Die *sp_die, void *data)
1889 struct dwarf_callback_param *param = data;
1890 struct line_finder *lf = param->data;
1891 struct line_range *lr = lf->lr;
1893 /* Check declared file */
1894 if (lr->file && strtailcmp(lr->file, dwarf_decl_file(sp_die)))
1897 if (die_match_name(sp_die, lr->function) && die_is_func_def(sp_die)) {
1898 lf->fname = dwarf_decl_file(sp_die);
1899 dwarf_decl_line(sp_die, &lr->offset);
1900 pr_debug("fname: %s, lineno:%d\n", lf->fname, lr->offset);
1901 lf->lno_s = lr->offset + lr->start;
1902 if (lf->lno_s < 0) /* Overflow */
1903 lf->lno_s = INT_MAX;
1904 lf->lno_e = lr->offset + lr->end;
1905 if (lf->lno_e < 0) /* Overflow */
1906 lf->lno_e = INT_MAX;
1907 pr_debug("New line range: %d to %d\n", lf->lno_s, lf->lno_e);
1908 lr->start = lf->lno_s;
1909 lr->end = lf->lno_e;
1910 if (!die_is_func_instance(sp_die))
1911 param->retval = die_walk_instances(sp_die,
1912 line_range_inline_cb, lf);
1914 param->retval = find_line_range_by_line(sp_die, lf);
1915 return DWARF_CB_ABORT;
1920 static int find_line_range_by_func(struct line_finder *lf)
1922 struct dwarf_callback_param param = {.data = (void *)lf, .retval = 0};
1923 dwarf_getfuncs(&lf->cu_die, line_range_search_cb, ¶m, 0);
1924 return param.retval;
1927 int debuginfo__find_line_range(struct debuginfo *dbg, struct line_range *lr)
1929 struct line_finder lf = {.lr = lr, .found = 0};
1931 Dwarf_Off off = 0, noff;
1934 const char *comp_dir;
1936 /* Fastpath: lookup by function name from .debug_pubnames section */
1938 struct pubname_callback_param pubname_param = {
1939 .function = lr->function, .file = lr->file,
1940 .cu_die = &lf.cu_die, .sp_die = &lf.sp_die, .found = 0};
1941 struct dwarf_callback_param line_range_param = {
1942 .data = (void *)&lf, .retval = 0};
1944 dwarf_getpubnames(dbg->dbg, pubname_search_cb,
1946 if (pubname_param.found) {
1947 line_range_search_cb(&lf.sp_die, &line_range_param);
1953 /* Loop on CUs (Compilation Unit) */
1954 while (!lf.found && ret >= 0) {
1955 if (dwarf_nextcu(dbg->dbg, off, &noff, &cuhl,
1956 NULL, NULL, NULL) != 0)
1959 /* Get the DIE(Debugging Information Entry) of this CU */
1960 diep = dwarf_offdie(dbg->dbg, off + cuhl, &lf.cu_die);
1966 /* Check if target file is included. */
1968 lf.fname = cu_find_realpath(&lf.cu_die, lr->file);
1972 if (!lr->file || lf.fname) {
1974 ret = find_line_range_by_func(&lf);
1976 lf.lno_s = lr->start;
1978 ret = find_line_range_by_line(NULL, &lf);
1985 /* Store comp_dir */
1987 comp_dir = cu_get_comp_dir(&lf.cu_die);
1989 lr->comp_dir = strdup(comp_dir);
1995 pr_debug("path: %s\n", lr->path);
1996 return (ret < 0) ? ret : lf.found;
1999 #ifdef HAVE_DEBUGINFOD_SUPPORT
2000 /* debuginfod doesn't require the comp_dir but buildid is required */
2001 static int get_source_from_debuginfod(const char *raw_path,
2002 const char *sbuild_id, char **new_path)
2004 debuginfod_client *c = debuginfod_begin();
2005 const char *p = raw_path;
2011 fd = debuginfod_find_source(c, (const unsigned char *)sbuild_id,
2013 pr_debug("Search %s from debuginfod -> %d\n", p, fd);
2018 pr_debug("Failed to find %s in debuginfod (%s)\n",
2019 raw_path, sbuild_id);
2022 pr_debug("Got a source %s\n", *new_path);
2027 static inline int get_source_from_debuginfod(const char *raw_path __maybe_unused,
2028 const char *sbuild_id __maybe_unused,
2029 char **new_path __maybe_unused)
2035 * Find a src file from a DWARF tag path. Prepend optional source path prefix
2036 * and chop off leading directories that do not exist. Result is passed back as
2037 * a newly allocated path on success.
2038 * Return 0 if file was found and readable, -errno otherwise.
2040 int find_source_path(const char *raw_path, const char *sbuild_id,
2041 const char *comp_dir, char **new_path)
2043 const char *prefix = symbol_conf.source_prefix;
2045 if (sbuild_id && !prefix) {
2046 if (!get_source_from_debuginfod(raw_path, sbuild_id, new_path))
2051 if (raw_path[0] != '/' && comp_dir)
2052 /* If not an absolute path, try to use comp_dir */
2055 if (access(raw_path, R_OK) == 0) {
2056 *new_path = strdup(raw_path);
2057 return *new_path ? 0 : -ENOMEM;
2063 *new_path = malloc((strlen(prefix) + strlen(raw_path) + 2));
2068 sprintf(*new_path, "%s/%s", prefix, raw_path);
2070 if (access(*new_path, R_OK) == 0)
2073 if (!symbol_conf.source_prefix) {
2074 /* In case of searching comp_dir, don't retry */
2084 raw_path = strchr(++raw_path, '/');