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Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / tools / perf / util / probe-finder.c
blob5d732621a462f31a57d9aa966fe80e23edacf4b8
1 /*
2 * probe-finder.c : C expression to kprobe event converter
3 *
4 * Written by Masami Hiramatsu <mhiramat@redhat.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19 *
20 */
21
22 #include <sys/utsname.h>
23 #include <sys/types.h>
24 #include <sys/stat.h>
25 #include <fcntl.h>
26 #include <errno.h>
27 #include <stdio.h>
28 #include <unistd.h>
29 #include <getopt.h>
30 #include <stdlib.h>
31 #include <string.h>
32 #include <stdarg.h>
33 #include <ctype.h>
34 #include <dwarf-regs.h>
35
36 #include <linux/bitops.h>
37 #include "event.h"
38 #include "debug.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 /* Line number list operations */
47
48 /* Add a line to line number list */
49 static int line_list__add_line(struct list_head *head, int line)
50 {
51 struct line_node *ln;
52 struct list_head *p;
53
54 /* Reverse search, because new line will be the last one */
55 list_for_each_entry_reverse(ln, head, list) {
56 if (ln->line < line) {
57 p = &ln->list;
58 goto found;
59 } else if (ln->line == line) /* Already exist */
60 return 1;
61 }
62 /* List is empty, or the smallest entry */
63 p = head;
64 found:
65 pr_debug("line list: add a line %u\n", line);
66 ln = zalloc(sizeof(struct line_node));
67 if (ln == NULL)
68 return -ENOMEM;
69 ln->line = line;
70 INIT_LIST_HEAD(&ln->list);
71 list_add(&ln->list, p);
72 return 0;
73 }
74
75 /* Check if the line in line number list */
76 static int line_list__has_line(struct list_head *head, int line)
77 {
78 struct line_node *ln;
79
80 /* Reverse search, because new line will be the last one */
81 list_for_each_entry(ln, head, list)
82 if (ln->line == line)
83 return 1;
84
85 return 0;
86 }
87
88 /* Init line number list */
89 static void line_list__init(struct list_head *head)
90 {
91 INIT_LIST_HEAD(head);
92 }
93
94 /* Free line number list */
95 static void line_list__free(struct list_head *head)
96 {
97 struct line_node *ln;
98 while (!list_empty(head)) {
99 ln = list_first_entry(head, struct line_node, list);
100 list_del(&ln->list);
101 free(ln);
102 }
103 }
104
105 /* Dwarf FL wrappers */
106 static char *debuginfo_path; /* Currently dummy */
107
108 static const Dwfl_Callbacks offline_callbacks = {
109 .find_debuginfo = dwfl_standard_find_debuginfo,
110 .debuginfo_path = &debuginfo_path,
111
112 .section_address = dwfl_offline_section_address,
113
114 /* We use this table for core files too. */
115 .find_elf = dwfl_build_id_find_elf,
116 };
117
118 /* Get a Dwarf from offline image */
119 static int debuginfo__init_offline_dwarf(struct debuginfo *self,
120 const char *path)
121 {
122 Dwfl_Module *mod;
123 int fd;
124
125 fd = open(path, O_RDONLY);
126 if (fd < 0)
127 return fd;
128
129 self->dwfl = dwfl_begin(&offline_callbacks);
130 if (!self->dwfl)
131 goto error;
132
133 mod = dwfl_report_offline(self->dwfl, "", "", fd);
134 if (!mod)
135 goto error;
136
137 self->dbg = dwfl_module_getdwarf(mod, &self->bias);
138 if (!self->dbg)
139 goto error;
140
141 return 0;
142 error:
143 if (self->dwfl)
144 dwfl_end(self->dwfl);
145 else
146 close(fd);
147 memset(self, 0, sizeof(*self));
148
149 return -ENOENT;
150 }
151
152 #if _ELFUTILS_PREREQ(0, 148)
153 /* This method is buggy if elfutils is older than 0.148 */
154 static int __linux_kernel_find_elf(Dwfl_Module *mod,
155 void **userdata,
156 const char *module_name,
157 Dwarf_Addr base,
158 char **file_name, Elf **elfp)
159 {
160 int fd;
161 const char *path = kernel_get_module_path(module_name);
162
163 pr_debug2("Use file %s for %s\n", path, module_name);
164 if (path) {
165 fd = open(path, O_RDONLY);
166 if (fd >= 0) {
167 *file_name = strdup(path);
168 return fd;
169 }
170 }
171 /* If failed, try to call standard method */
172 return dwfl_linux_kernel_find_elf(mod, userdata, module_name, base,
173 file_name, elfp);
174 }
175
176 static const Dwfl_Callbacks kernel_callbacks = {
177 .find_debuginfo = dwfl_standard_find_debuginfo,
178 .debuginfo_path = &debuginfo_path,
179
180 .find_elf = __linux_kernel_find_elf,
181 .section_address = dwfl_linux_kernel_module_section_address,
182 };
183
184 /* Get a Dwarf from live kernel image */
185 static int debuginfo__init_online_kernel_dwarf(struct debuginfo *self,
186 Dwarf_Addr addr)
187 {
188 self->dwfl = dwfl_begin(&kernel_callbacks);
189 if (!self->dwfl)
190 return -EINVAL;
191
192 /* Load the kernel dwarves: Don't care the result here */
193 dwfl_linux_kernel_report_kernel(self->dwfl);
194 dwfl_linux_kernel_report_modules(self->dwfl);
195
196 self->dbg = dwfl_addrdwarf(self->dwfl, addr, &self->bias);
197 /* Here, check whether we could get a real dwarf */
198 if (!self->dbg) {
199 pr_debug("Failed to find kernel dwarf at %lx\n",
200 (unsigned long)addr);
201 dwfl_end(self->dwfl);
202 memset(self, 0, sizeof(*self));
203 return -ENOENT;
204 }
205
206 return 0;
207 }
208 #else
209 /* With older elfutils, this just support kernel module... */
210 static int debuginfo__init_online_kernel_dwarf(struct debuginfo *self,
211 Dwarf_Addr addr __used)
212 {
213 const char *path = kernel_get_module_path("kernel");
214
215 if (!path) {
216 pr_err("Failed to find vmlinux path\n");
217 return -ENOENT;
218 }
219
220 pr_debug2("Use file %s for debuginfo\n", path);
221 return debuginfo__init_offline_dwarf(self, path);
222 }
223 #endif
224
225 struct debuginfo *debuginfo__new(const char *path)
226 {
227 struct debuginfo *self = zalloc(sizeof(struct debuginfo));
228 if (!self)
229 return NULL;
230
231 if (debuginfo__init_offline_dwarf(self, path) < 0) {
232 free(self);
233 self = NULL;
234 }
235
236 return self;
237 }
238
239 struct debuginfo *debuginfo__new_online_kernel(unsigned long addr)
240 {
241 struct debuginfo *self = zalloc(sizeof(struct debuginfo));
242 if (!self)
243 return NULL;
244
245 if (debuginfo__init_online_kernel_dwarf(self, (Dwarf_Addr)addr) < 0) {
246 free(self);
247 self = NULL;
248 }
249
250 return self;
251 }
252
253 void debuginfo__delete(struct debuginfo *self)
254 {
255 if (self) {
256 if (self->dwfl)
257 dwfl_end(self->dwfl);
258 free(self);
259 }
260 }
261
262 /*
263 * Probe finder related functions
264 */
265
266 static struct probe_trace_arg_ref *alloc_trace_arg_ref(long offs)
267 {
268 struct probe_trace_arg_ref *ref;
269 ref = zalloc(sizeof(struct probe_trace_arg_ref));
270 if (ref != NULL)
271 ref->offset = offs;
272 return ref;
273 }
274
275 /*
276 * Convert a location into trace_arg.
277 * If tvar == NULL, this just checks variable can be converted.
278 */
279 static int convert_variable_location(Dwarf_Die *vr_die, Dwarf_Addr addr,
280 Dwarf_Op *fb_ops,
281 struct probe_trace_arg *tvar)
282 {
283 Dwarf_Attribute attr;
284 Dwarf_Op *op;
285 size_t nops;
286 unsigned int regn;
287 Dwarf_Word offs = 0;
288 bool ref = false;
289 const char *regs;
290 int ret;
291
292 if (dwarf_attr(vr_die, DW_AT_external, &attr) != NULL)
293 goto static_var;
294
295 /* TODO: handle more than 1 exprs */
296 if (dwarf_attr(vr_die, DW_AT_location, &attr) == NULL ||
297 dwarf_getlocation_addr(&attr, addr, &op, &nops, 1) <= 0 ||
298 nops == 0) {
299 /* TODO: Support const_value */
300 return -ENOENT;
301 }
302
303 if (op->atom == DW_OP_addr) {
304 static_var:
305 if (!tvar)
306 return 0;
307 /* Static variables on memory (not stack), make @varname */
308 ret = strlen(dwarf_diename(vr_die));
309 tvar->value = zalloc(ret + 2);
310 if (tvar->value == NULL)
311 return -ENOMEM;
312 snprintf(tvar->value, ret + 2, "@%s", dwarf_diename(vr_die));
313 tvar->ref = alloc_trace_arg_ref((long)offs);
314 if (tvar->ref == NULL)
315 return -ENOMEM;
316 return 0;
317 }
318
319 /* If this is based on frame buffer, set the offset */
320 if (op->atom == DW_OP_fbreg) {
321 if (fb_ops == NULL)
322 return -ENOTSUP;
323 ref = true;
324 offs = op->number;
325 op = &fb_ops[0];
326 }
327
328 if (op->atom >= DW_OP_breg0 && op->atom <= DW_OP_breg31) {
329 regn = op->atom - DW_OP_breg0;
330 offs += op->number;
331 ref = true;
332 } else if (op->atom >= DW_OP_reg0 && op->atom <= DW_OP_reg31) {
333 regn = op->atom - DW_OP_reg0;
334 } else if (op->atom == DW_OP_bregx) {
335 regn = op->number;
336 offs += op->number2;
337 ref = true;
338 } else if (op->atom == DW_OP_regx) {
339 regn = op->number;
340 } else {
341 pr_debug("DW_OP %x is not supported.\n", op->atom);
342 return -ENOTSUP;
343 }
344
345 if (!tvar)
346 return 0;
347
348 regs = get_arch_regstr(regn);
349 if (!regs) {
350 /* This should be a bug in DWARF or this tool */
351 pr_warning("Mapping for the register number %u "
352 "missing on this architecture.\n", regn);
353 return -ERANGE;
354 }
355
356 tvar->value = strdup(regs);
357 if (tvar->value == NULL)
358 return -ENOMEM;
359
360 if (ref) {
361 tvar->ref = alloc_trace_arg_ref((long)offs);
362 if (tvar->ref == NULL)
363 return -ENOMEM;
364 }
365 return 0;
366 }
367
368 #define BYTES_TO_BITS(nb) ((nb) * BITS_PER_LONG / sizeof(long))
369
370 static int convert_variable_type(Dwarf_Die *vr_die,
371 struct probe_trace_arg *tvar,
372 const char *cast)
373 {
374 struct probe_trace_arg_ref **ref_ptr = &tvar->ref;
375 Dwarf_Die type;
376 char buf[16];
377 int bsize, boffs, total;
378 int ret;
379
380 /* TODO: check all types */
381 if (cast && strcmp(cast, "string") != 0) {
382 /* Non string type is OK */
383 tvar->type = strdup(cast);
384 return (tvar->type == NULL) ? -ENOMEM : 0;
385 }
386
387 bsize = dwarf_bitsize(vr_die);
388 if (bsize > 0) {
389 /* This is a bitfield */
390 boffs = dwarf_bitoffset(vr_die);
391 total = dwarf_bytesize(vr_die);
392 if (boffs < 0 || total < 0)
393 return -ENOENT;
394 ret = snprintf(buf, 16, "b%d@%d/%zd", bsize, boffs,
395 BYTES_TO_BITS(total));
396 goto formatted;
397 }
398
399 if (die_get_real_type(vr_die, &type) == NULL) {
400 pr_warning("Failed to get a type information of %s.\n",
401 dwarf_diename(vr_die));
402 return -ENOENT;
403 }
404
405 pr_debug("%s type is %s.\n",
406 dwarf_diename(vr_die), dwarf_diename(&type));
407
408 if (cast && strcmp(cast, "string") == 0) { /* String type */
409 ret = dwarf_tag(&type);
410 if (ret != DW_TAG_pointer_type &&
411 ret != DW_TAG_array_type) {
412 pr_warning("Failed to cast into string: "
413 "%s(%s) is not a pointer nor array.\n",
414 dwarf_diename(vr_die), dwarf_diename(&type));
415 return -EINVAL;
416 }
417 if (ret == DW_TAG_pointer_type) {
418 if (die_get_real_type(&type, &type) == NULL) {
419 pr_warning("Failed to get a type"
420 " information.\n");
421 return -ENOENT;
422 }
423 while (*ref_ptr)
424 ref_ptr = &(*ref_ptr)->next;
425 /* Add new reference with offset +0 */
426 *ref_ptr = zalloc(sizeof(struct probe_trace_arg_ref));
427 if (*ref_ptr == NULL) {
428 pr_warning("Out of memory error\n");
429 return -ENOMEM;
430 }
431 }
432 if (!die_compare_name(&type, "char") &&
433 !die_compare_name(&type, "unsigned char")) {
434 pr_warning("Failed to cast into string: "
435 "%s is not (unsigned) char *.\n",
436 dwarf_diename(vr_die));
437 return -EINVAL;
438 }
439 tvar->type = strdup(cast);
440 return (tvar->type == NULL) ? -ENOMEM : 0;
441 }
442
443 ret = dwarf_bytesize(&type);
444 if (ret <= 0)
445 /* No size ... try to use default type */
446 return 0;
447 ret = BYTES_TO_BITS(ret);
448
449 /* Check the bitwidth */
450 if (ret > MAX_BASIC_TYPE_BITS) {
451 pr_info("%s exceeds max-bitwidth. Cut down to %d bits.\n",
452 dwarf_diename(&type), MAX_BASIC_TYPE_BITS);
453 ret = MAX_BASIC_TYPE_BITS;
454 }
455 ret = snprintf(buf, 16, "%c%d",
456 die_is_signed_type(&type) ? 's' : 'u', ret);
457
458 formatted:
459 if (ret < 0 || ret >= 16) {
460 if (ret >= 16)
461 ret = -E2BIG;
462 pr_warning("Failed to convert variable type: %s\n",
463 strerror(-ret));
464 return ret;
465 }
466 tvar->type = strdup(buf);
467 if (tvar->type == NULL)
468 return -ENOMEM;
469 return 0;
470 }
471
472 static int convert_variable_fields(Dwarf_Die *vr_die, const char *varname,
473 struct perf_probe_arg_field *field,
474 struct probe_trace_arg_ref **ref_ptr,
475 Dwarf_Die *die_mem)
476 {
477 struct probe_trace_arg_ref *ref = *ref_ptr;
478 Dwarf_Die type;
479 Dwarf_Word offs;
480 int ret, tag;
481
482 pr_debug("converting %s in %s\n", field->name, varname);
483 if (die_get_real_type(vr_die, &type) == NULL) {
484 pr_warning("Failed to get the type of %s.\n", varname);
485 return -ENOENT;
486 }
487 pr_debug2("Var real type: (%x)\n", (unsigned)dwarf_dieoffset(&type));
488 tag = dwarf_tag(&type);
489
490 if (field->name[0] == '[' &&
491 (tag == DW_TAG_array_type || tag == DW_TAG_pointer_type)) {
492 if (field->next)
493 /* Save original type for next field */
494 memcpy(die_mem, &type, sizeof(*die_mem));
495 /* Get the type of this array */
496 if (die_get_real_type(&type, &type) == NULL) {
497 pr_warning("Failed to get the type of %s.\n", varname);
498 return -ENOENT;
499 }
500 pr_debug2("Array real type: (%x)\n",
501 (unsigned)dwarf_dieoffset(&type));
502 if (tag == DW_TAG_pointer_type) {
503 ref = zalloc(sizeof(struct probe_trace_arg_ref));
504 if (ref == NULL)
505 return -ENOMEM;
506 if (*ref_ptr)
507 (*ref_ptr)->next = ref;
508 else
509 *ref_ptr = ref;
510 }
511 ref->offset += dwarf_bytesize(&type) * field->index;
512 if (!field->next)
513 /* Save vr_die for converting types */
514 memcpy(die_mem, vr_die, sizeof(*die_mem));
515 goto next;
516 } else if (tag == DW_TAG_pointer_type) {
517 /* Check the pointer and dereference */
518 if (!field->ref) {
519 pr_err("Semantic error: %s must be referred by '->'\n",
520 field->name);
521 return -EINVAL;
522 }
523 /* Get the type pointed by this pointer */
524 if (die_get_real_type(&type, &type) == NULL) {
525 pr_warning("Failed to get the type of %s.\n", varname);
526 return -ENOENT;
527 }
528 /* Verify it is a data structure */
529 if (dwarf_tag(&type) != DW_TAG_structure_type) {
530 pr_warning("%s is not a data structure.\n", varname);
531 return -EINVAL;
532 }
533
534 ref = zalloc(sizeof(struct probe_trace_arg_ref));
535 if (ref == NULL)
536 return -ENOMEM;
537 if (*ref_ptr)
538 (*ref_ptr)->next = ref;
539 else
540 *ref_ptr = ref;
541 } else {
542 /* Verify it is a data structure */
543 if (tag != DW_TAG_structure_type) {
544 pr_warning("%s is not a data structure.\n", varname);
545 return -EINVAL;
546 }
547 if (field->name[0] == '[') {
548 pr_err("Semantic error: %s is not a pointor"
549 " nor array.\n", varname);
550 return -EINVAL;
551 }
552 if (field->ref) {
553 pr_err("Semantic error: %s must be referred by '.'\n",
554 field->name);
555 return -EINVAL;
556 }
557 if (!ref) {
558 pr_warning("Structure on a register is not "
559 "supported yet.\n");
560 return -ENOTSUP;
561 }
562 }
563
564 if (die_find_member(&type, field->name, die_mem) == NULL) {
565 pr_warning("%s(tyep:%s) has no member %s.\n", varname,
566 dwarf_diename(&type), field->name);
567 return -EINVAL;
568 }
569
570 /* Get the offset of the field */
571 ret = die_get_data_member_location(die_mem, &offs);
572 if (ret < 0) {
573 pr_warning("Failed to get the offset of %s.\n", field->name);
574 return ret;
575 }
576 ref->offset += (long)offs;
577
578 next:
579 /* Converting next field */
580 if (field->next)
581 return convert_variable_fields(die_mem, field->name,
582 field->next, &ref, die_mem);
583 else
584 return 0;
585 }
586
587 /* Show a variables in kprobe event format */
588 static int convert_variable(Dwarf_Die *vr_die, struct probe_finder *pf)
589 {
590 Dwarf_Die die_mem;
591 int ret;
592
593 pr_debug("Converting variable %s into trace event.\n",
594 dwarf_diename(vr_die));
595
596 ret = convert_variable_location(vr_die, pf->addr, pf->fb_ops,
597 pf->tvar);
598 if (ret == -ENOENT)
599 pr_err("Failed to find the location of %s at this address.\n"
600 " Perhaps, it has been optimized out.\n", pf->pvar->var);
601 else if (ret == -ENOTSUP)
602 pr_err("Sorry, we don't support this variable location yet.\n");
603 else if (pf->pvar->field) {
604 ret = convert_variable_fields(vr_die, pf->pvar->var,
605 pf->pvar->field, &pf->tvar->ref,
606 &die_mem);
607 vr_die = &die_mem;
608 }
609 if (ret == 0)
610 ret = convert_variable_type(vr_die, pf->tvar, pf->pvar->type);
611 /* *expr will be cached in libdw. Don't free it. */
612 return ret;
613 }
614
615 /* Find a variable in a scope DIE */
616 static int find_variable(Dwarf_Die *sc_die, struct probe_finder *pf)
617 {
618 Dwarf_Die vr_die;
619 char buf[32], *ptr;
620 int ret = 0;
621
622 if (!is_c_varname(pf->pvar->var)) {
623 /* Copy raw parameters */
624 pf->tvar->value = strdup(pf->pvar->var);
625 if (pf->tvar->value == NULL)
626 return -ENOMEM;
627 if (pf->pvar->type) {
628 pf->tvar->type = strdup(pf->pvar->type);
629 if (pf->tvar->type == NULL)
630 return -ENOMEM;
631 }
632 if (pf->pvar->name) {
633 pf->tvar->name = strdup(pf->pvar->name);
634 if (pf->tvar->name == NULL)
635 return -ENOMEM;
636 } else
637 pf->tvar->name = NULL;
638 return 0;
639 }
640
641 if (pf->pvar->name)
642 pf->tvar->name = strdup(pf->pvar->name);
643 else {
644 ret = synthesize_perf_probe_arg(pf->pvar, buf, 32);
645 if (ret < 0)
646 return ret;
647 ptr = strchr(buf, ':'); /* Change type separator to _ */
648 if (ptr)
649 *ptr = '_';
650 pf->tvar->name = strdup(buf);
651 }
652 if (pf->tvar->name == NULL)
653 return -ENOMEM;
654
655 pr_debug("Searching '%s' variable in context.\n", pf->pvar->var);
656 /* Search child die for local variables and parameters. */
657 if (!die_find_variable_at(sc_die, pf->pvar->var, pf->addr, &vr_die)) {
658 /* Search again in global variables */
659 if (!die_find_variable_at(&pf->cu_die, pf->pvar->var, 0, &vr_die))
660 ret = -ENOENT;
661 }
662 if (ret >= 0)
663 ret = convert_variable(&vr_die, pf);
664
665 if (ret < 0)
666 pr_warning("Failed to find '%s' in this function.\n",
667 pf->pvar->var);
668 return ret;
669 }
670
671 /* Convert subprogram DIE to trace point */
672 static int convert_to_trace_point(Dwarf_Die *sp_die, Dwarf_Addr paddr,
673 bool retprobe, struct probe_trace_point *tp)
674 {
675 Dwarf_Addr eaddr;
676 const char *name;
677
678 /* Copy the name of probe point */
679 name = dwarf_diename(sp_die);
680 if (name) {
681 if (dwarf_entrypc(sp_die, &eaddr) != 0) {
682 pr_warning("Failed to get entry address of %s\n",
683 dwarf_diename(sp_die));
684 return -ENOENT;
685 }
686 tp->symbol = strdup(name);
687 if (tp->symbol == NULL)
688 return -ENOMEM;
689 tp->offset = (unsigned long)(paddr - eaddr);
690 } else
691 /* This function has no name. */
692 tp->offset = (unsigned long)paddr;
693
694 /* Return probe must be on the head of a subprogram */
695 if (retprobe) {
696 if (eaddr != paddr) {
697 pr_warning("Return probe must be on the head of"
698 " a real function.\n");
699 return -EINVAL;
700 }
701 tp->retprobe = true;
702 }
703
704 return 0;
705 }
706
707 /* Call probe_finder callback with scope DIE */
708 static int call_probe_finder(Dwarf_Die *sc_die, struct probe_finder *pf)
709 {
710 Dwarf_Attribute fb_attr;
711 size_t nops;
712 int ret;
713
714 if (!sc_die) {
715 pr_err("Caller must pass a scope DIE. Program error.\n");
716 return -EINVAL;
717 }
718
719 /* If not a real subprogram, find a real one */
720 if (dwarf_tag(sc_die) != DW_TAG_subprogram) {
721 if (!die_find_realfunc(&pf->cu_die, pf->addr, &pf->sp_die)) {
722 pr_warning("Failed to find probe point in any "
723 "functions.\n");
724 return -ENOENT;
725 }
726 } else
727 memcpy(&pf->sp_die, sc_die, sizeof(Dwarf_Die));
728
729 /* Get the frame base attribute/ops from subprogram */
730 dwarf_attr(&pf->sp_die, DW_AT_frame_base, &fb_attr);
731 ret = dwarf_getlocation_addr(&fb_attr, pf->addr, &pf->fb_ops, &nops, 1);
732 if (ret <= 0 || nops == 0) {
733 pf->fb_ops = NULL;
734 #if _ELFUTILS_PREREQ(0, 142)
735 } else if (nops == 1 && pf->fb_ops[0].atom == DW_OP_call_frame_cfa &&
736 pf->cfi != NULL) {
737 Dwarf_Frame *frame;
738 if (dwarf_cfi_addrframe(pf->cfi, pf->addr, &frame) != 0 ||
739 dwarf_frame_cfa(frame, &pf->fb_ops, &nops) != 0) {
740 pr_warning("Failed to get call frame on 0x%jx\n",
741 (uintmax_t)pf->addr);
742 return -ENOENT;
743 }
744 #endif
745 }
746
747 /* Call finder's callback handler */
748 ret = pf->callback(sc_die, pf);
749
750 /* *pf->fb_ops will be cached in libdw. Don't free it. */
751 pf->fb_ops = NULL;
752
753 return ret;
754 }
755
756 struct find_scope_param {
757 const char *function;
758 const char *file;
759 int line;
760 int diff;
761 Dwarf_Die *die_mem;
762 bool found;
763 };
764
765 static int find_best_scope_cb(Dwarf_Die *fn_die, void *data)
766 {
767 struct find_scope_param *fsp = data;
768 const char *file;
769 int lno;
770
771 /* Skip if declared file name does not match */
772 if (fsp->file) {
773 file = dwarf_decl_file(fn_die);
774 if (!file || strcmp(fsp->file, file) != 0)
775 return 0;
776 }
777 /* If the function name is given, that's what user expects */
778 if (fsp->function) {
779 if (die_compare_name(fn_die, fsp->function)) {
780 memcpy(fsp->die_mem, fn_die, sizeof(Dwarf_Die));
781 fsp->found = true;
782 return 1;
783 }
784 } else {
785 /* With the line number, find the nearest declared DIE */
786 dwarf_decl_line(fn_die, &lno);
787 if (lno < fsp->line && fsp->diff > fsp->line - lno) {
788 /* Keep a candidate and continue */
789 fsp->diff = fsp->line - lno;
790 memcpy(fsp->die_mem, fn_die, sizeof(Dwarf_Die));
791 fsp->found = true;
792 }
793 }
794 return 0;
795 }
796
797 /* Find an appropriate scope fits to given conditions */
798 static Dwarf_Die *find_best_scope(struct probe_finder *pf, Dwarf_Die *die_mem)
799 {
800 struct find_scope_param fsp = {
801 .function = pf->pev->point.function,
802 .file = pf->fname,
803 .line = pf->lno,
804 .diff = INT_MAX,
805 .die_mem = die_mem,
806 .found = false,
807 };
808
809 cu_walk_functions_at(&pf->cu_die, pf->addr, find_best_scope_cb, &fsp);
810
811 return fsp.found ? die_mem : NULL;
812 }
813
814 static int probe_point_line_walker(const char *fname, int lineno,
815 Dwarf_Addr addr, void *data)
816 {
817 struct probe_finder *pf = data;
818 Dwarf_Die *sc_die, die_mem;
819 int ret;
820
821 if (lineno != pf->lno || strtailcmp(fname, pf->fname) != 0)
822 return 0;
823
824 pf->addr = addr;
825 sc_die = find_best_scope(pf, &die_mem);
826 if (!sc_die) {
827 pr_warning("Failed to find scope of probe point.\n");
828 return -ENOENT;
829 }
830
831 ret = call_probe_finder(sc_die, pf);
832
833 /* Continue if no error, because the line will be in inline function */
834 return ret < 0 ? ret : 0;
835 }
836
837 /* Find probe point from its line number */
838 static int find_probe_point_by_line(struct probe_finder *pf)
839 {
840 return die_walk_lines(&pf->cu_die, probe_point_line_walker, pf);
841 }
842
843 /* Find lines which match lazy pattern */
844 static int find_lazy_match_lines(struct list_head *head,
845 const char *fname, const char *pat)
846 {
847 FILE *fp;
848 char *line = NULL;
849 size_t line_len;
850 ssize_t len;
851 int count = 0, linenum = 1;
852
853 fp = fopen(fname, "r");
854 if (!fp) {
855 pr_warning("Failed to open %s: %s\n", fname, strerror(errno));
856 return -errno;
857 }
858
859 while ((len = getline(&line, &line_len, fp)) > 0) {
860
861 if (line[len - 1] == '\n')
862 line[len - 1] = '\0';
863
864 if (strlazymatch(line, pat)) {
865 line_list__add_line(head, linenum);
866 count++;
867 }
868 linenum++;
869 }
870
871 if (ferror(fp))
872 count = -errno;
873 free(line);
874 fclose(fp);
875
876 if (count == 0)
877 pr_debug("No matched lines found in %s.\n", fname);
878 return count;
879 }
880
881 static int probe_point_lazy_walker(const char *fname, int lineno,
882 Dwarf_Addr addr, void *data)
883 {
884 struct probe_finder *pf = data;
885 Dwarf_Die *sc_die, die_mem;
886 int ret;
887
888 if (!line_list__has_line(&pf->lcache, lineno) ||
889 strtailcmp(fname, pf->fname) != 0)
890 return 0;
891
892 pr_debug("Probe line found: line:%d addr:0x%llx\n",
893 lineno, (unsigned long long)addr);
894 pf->addr = addr;
895 pf->lno = lineno;
896 sc_die = find_best_scope(pf, &die_mem);
897 if (!sc_die) {
898 pr_warning("Failed to find scope of probe point.\n");
899 return -ENOENT;
900 }
901
902 ret = call_probe_finder(sc_die, pf);
903
904 /*
905 * Continue if no error, because the lazy pattern will match
906 * to other lines
907 */
908 return ret < 0 ? ret : 0;
909 }
910
911 /* Find probe points from lazy pattern */
912 static int find_probe_point_lazy(Dwarf_Die *sp_die, struct probe_finder *pf)
913 {
914 int ret = 0;
915
916 if (list_empty(&pf->lcache)) {
917 /* Matching lazy line pattern */
918 ret = find_lazy_match_lines(&pf->lcache, pf->fname,
919 pf->pev->point.lazy_line);
920 if (ret <= 0)
921 return ret;
922 }
923
924 return die_walk_lines(sp_die, probe_point_lazy_walker, pf);
925 }
926
927 static int probe_point_inline_cb(Dwarf_Die *in_die, void *data)
928 {
929 struct probe_finder *pf = data;
930 struct perf_probe_point *pp = &pf->pev->point;
931 Dwarf_Addr addr;
932 int ret;
933
934 if (pp->lazy_line)
935 ret = find_probe_point_lazy(in_die, pf);
936 else {
937 /* Get probe address */
938 if (dwarf_entrypc(in_die, &addr) != 0) {
939 pr_warning("Failed to get entry address of %s.\n",
940 dwarf_diename(in_die));
941 return -ENOENT;
942 }
943 pf->addr = addr;
944 pf->addr += pp->offset;
945 pr_debug("found inline addr: 0x%jx\n",
946 (uintmax_t)pf->addr);
947
948 ret = call_probe_finder(in_die, pf);
949 }
950
951 return ret;
952 }
953
954 /* Callback parameter with return value for libdw */
955 struct dwarf_callback_param {
956 void *data;
957 int retval;
958 };
959
960 /* Search function from function name */
961 static int probe_point_search_cb(Dwarf_Die *sp_die, void *data)
962 {
963 struct dwarf_callback_param *param = data;
964 struct probe_finder *pf = param->data;
965 struct perf_probe_point *pp = &pf->pev->point;
966
967 /* Check tag and diename */
968 if (dwarf_tag(sp_die) != DW_TAG_subprogram ||
969 !die_compare_name(sp_die, pp->function))
970 return DWARF_CB_OK;
971
972 /* Check declared file */
973 if (pp->file && strtailcmp(pp->file, dwarf_decl_file(sp_die)))
974 return DWARF_CB_OK;
975
976 pf->fname = dwarf_decl_file(sp_die);
977 if (pp->line) { /* Function relative line */
978 dwarf_decl_line(sp_die, &pf->lno);
979 pf->lno += pp->line;
980 param->retval = find_probe_point_by_line(pf);
981 } else if (!dwarf_func_inline(sp_die)) {
982 /* Real function */
983 if (pp->lazy_line)
984 param->retval = find_probe_point_lazy(sp_die, pf);
985 else {
986 if (dwarf_entrypc(sp_die, &pf->addr) != 0) {
987 pr_warning("Failed to get entry address of "
988 "%s.\n", dwarf_diename(sp_die));
989 param->retval = -ENOENT;
990 return DWARF_CB_ABORT;
991 }
992 pf->addr += pp->offset;
993 /* TODO: Check the address in this function */
994 param->retval = call_probe_finder(sp_die, pf);
995 }
996 } else
997 /* Inlined function: search instances */
998 param->retval = die_walk_instances(sp_die,
999 probe_point_inline_cb, (void *)pf);
1000
1001 return DWARF_CB_ABORT; /* Exit; no same symbol in this CU. */
1002 }
1003
1004 static int find_probe_point_by_func(struct probe_finder *pf)
1005 {
1006 struct dwarf_callback_param _param = {.data = (void *)pf,
1007 .retval = 0};
1008 dwarf_getfuncs(&pf->cu_die, probe_point_search_cb, &_param, 0);
1009 return _param.retval;
1010 }
1011
1012 struct pubname_callback_param {
1013 char *function;
1014 char *file;
1015 Dwarf_Die *cu_die;
1016 Dwarf_Die *sp_die;
1017 int found;
1018 };
1019
1020 static int pubname_search_cb(Dwarf *dbg, Dwarf_Global *gl, void *data)
1021 {
1022 struct pubname_callback_param *param = data;
1023
1024 if (dwarf_offdie(dbg, gl->die_offset, param->sp_die)) {
1025 if (dwarf_tag(param->sp_die) != DW_TAG_subprogram)
1026 return DWARF_CB_OK;
1027
1028 if (die_compare_name(param->sp_die, param->function)) {
1029 if (!dwarf_offdie(dbg, gl->cu_offset, param->cu_die))
1030 return DWARF_CB_OK;
1031
1032 if (param->file &&
1033 strtailcmp(param->file, dwarf_decl_file(param->sp_die)))
1034 return DWARF_CB_OK;
1035
1036 param->found = 1;
1037 return DWARF_CB_ABORT;
1038 }
1039 }
1040
1041 return DWARF_CB_OK;
1042 }
1043
1044 /* Find probe points from debuginfo */
1045 static int debuginfo__find_probes(struct debuginfo *self,
1046 struct probe_finder *pf)
1047 {
1048 struct perf_probe_point *pp = &pf->pev->point;
1049 Dwarf_Off off, noff;
1050 size_t cuhl;
1051 Dwarf_Die *diep;
1052 int ret = 0;
1053
1054 #if _ELFUTILS_PREREQ(0, 142)
1055 /* Get the call frame information from this dwarf */
1056 pf->cfi = dwarf_getcfi(self->dbg);
1057 #endif
1058
1059 off = 0;
1060 line_list__init(&pf->lcache);
1061
1062 /* Fastpath: lookup by function name from .debug_pubnames section */
1063 if (pp->function) {
1064 struct pubname_callback_param pubname_param = {
1065 .function = pp->function,
1066 .file = pp->file,
1067 .cu_die = &pf->cu_die,
1068 .sp_die = &pf->sp_die,
1069 .found = 0,
1070 };
1071 struct dwarf_callback_param probe_param = {
1072 .data = pf,
1073 };
1074
1075 dwarf_getpubnames(self->dbg, pubname_search_cb,
1076 &pubname_param, 0);
1077 if (pubname_param.found) {
1078 ret = probe_point_search_cb(&pf->sp_die, &probe_param);
1079 if (ret)
1080 goto found;
1081 }
1082 }
1083
1084 /* Loop on CUs (Compilation Unit) */
1085 while (!dwarf_nextcu(self->dbg, off, &noff, &cuhl, NULL, NULL, NULL)) {
1086 /* Get the DIE(Debugging Information Entry) of this CU */
1087 diep = dwarf_offdie(self->dbg, off + cuhl, &pf->cu_die);
1088 if (!diep)
1089 continue;
1090
1091 /* Check if target file is included. */
1092 if (pp->file)
1093 pf->fname = cu_find_realpath(&pf->cu_die, pp->file);
1094 else
1095 pf->fname = NULL;
1096
1097 if (!pp->file || pf->fname) {
1098 if (pp->function)
1099 ret = find_probe_point_by_func(pf);
1100 else if (pp->lazy_line)
1101 ret = find_probe_point_lazy(NULL, pf);
1102 else {
1103 pf->lno = pp->line;
1104 ret = find_probe_point_by_line(pf);
1105 }
1106 if (ret < 0)
1107 break;
1108 }
1109 off = noff;
1110 }
1111
1112 found:
1113 line_list__free(&pf->lcache);
1114
1115 return ret;
1116 }
1117
1118 /* Add a found probe point into trace event list */
1119 static int add_probe_trace_event(Dwarf_Die *sc_die, struct probe_finder *pf)
1120 {
1121 struct trace_event_finder *tf =
1122 container_of(pf, struct trace_event_finder, pf);
1123 struct probe_trace_event *tev;
1124 int ret, i;
1125
1126 /* Check number of tevs */
1127 if (tf->ntevs == tf->max_tevs) {
1128 pr_warning("Too many( > %d) probe point found.\n",
1129 tf->max_tevs);
1130 return -ERANGE;
1131 }
1132 tev = &tf->tevs[tf->ntevs++];
1133
1134 /* Trace point should be converted from subprogram DIE */
1135 ret = convert_to_trace_point(&pf->sp_die, pf->addr,
1136 pf->pev->point.retprobe, &tev->point);
1137 if (ret < 0)
1138 return ret;
1139
1140 pr_debug("Probe point found: %s+%lu\n", tev->point.symbol,
1141 tev->point.offset);
1142
1143 /* Find each argument */
1144 tev->nargs = pf->pev->nargs;
1145 tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
1146 if (tev->args == NULL)
1147 return -ENOMEM;
1148 for (i = 0; i < pf->pev->nargs; i++) {
1149 pf->pvar = &pf->pev->args[i];
1150 pf->tvar = &tev->args[i];
1151 /* Variable should be found from scope DIE */
1152 ret = find_variable(sc_die, pf);
1153 if (ret != 0)
1154 return ret;
1155 }
1156
1157 return 0;
1158 }
1159
1160 /* Find probe_trace_events specified by perf_probe_event from debuginfo */
1161 int debuginfo__find_trace_events(struct debuginfo *self,
1162 struct perf_probe_event *pev,
1163 struct probe_trace_event **tevs, int max_tevs)
1164 {
1165 struct trace_event_finder tf = {
1166 .pf = {.pev = pev, .callback = add_probe_trace_event},
1167 .max_tevs = max_tevs};
1168 int ret;
1169
1170 /* Allocate result tevs array */
1171 *tevs = zalloc(sizeof(struct probe_trace_event) * max_tevs);
1172 if (*tevs == NULL)
1173 return -ENOMEM;
1174
1175 tf.tevs = *tevs;
1176 tf.ntevs = 0;
1177
1178 ret = debuginfo__find_probes(self, &tf.pf);
1179 if (ret < 0) {
1180 free(*tevs);
1181 *tevs = NULL;
1182 return ret;
1183 }
1184
1185 return (ret < 0) ? ret : tf.ntevs;
1186 }
1187
1188 #define MAX_VAR_LEN 64
1189
1190 /* Collect available variables in this scope */
1191 static int collect_variables_cb(Dwarf_Die *die_mem, void *data)
1192 {
1193 struct available_var_finder *af = data;
1194 struct variable_list *vl;
1195 char buf[MAX_VAR_LEN];
1196 int tag, ret;
1197
1198 vl = &af->vls[af->nvls - 1];
1199
1200 tag = dwarf_tag(die_mem);
1201 if (tag == DW_TAG_formal_parameter ||
1202 tag == DW_TAG_variable) {
1203 ret = convert_variable_location(die_mem, af->pf.addr,
1204 af->pf.fb_ops, NULL);
1205 if (ret == 0) {
1206 ret = die_get_varname(die_mem, buf, MAX_VAR_LEN);
1207 pr_debug2("Add new var: %s\n", buf);
1208 if (ret > 0)
1209 strlist__add(vl->vars, buf);
1210 }
1211 }
1212
1213 if (af->child && dwarf_haspc(die_mem, af->pf.addr))
1214 return DIE_FIND_CB_CONTINUE;
1215 else
1216 return DIE_FIND_CB_SIBLING;
1217 }
1218
1219 /* Add a found vars into available variables list */
1220 static int add_available_vars(Dwarf_Die *sc_die, struct probe_finder *pf)
1221 {
1222 struct available_var_finder *af =
1223 container_of(pf, struct available_var_finder, pf);
1224 struct variable_list *vl;
1225 Dwarf_Die die_mem;
1226 int ret;
1227
1228 /* Check number of tevs */
1229 if (af->nvls == af->max_vls) {
1230 pr_warning("Too many( > %d) probe point found.\n", af->max_vls);
1231 return -ERANGE;
1232 }
1233 vl = &af->vls[af->nvls++];
1234
1235 /* Trace point should be converted from subprogram DIE */
1236 ret = convert_to_trace_point(&pf->sp_die, pf->addr,
1237 pf->pev->point.retprobe, &vl->point);
1238 if (ret < 0)
1239 return ret;
1240
1241 pr_debug("Probe point found: %s+%lu\n", vl->point.symbol,
1242 vl->point.offset);
1243
1244 /* Find local variables */
1245 vl->vars = strlist__new(true, NULL);
1246 if (vl->vars == NULL)
1247 return -ENOMEM;
1248 af->child = true;
1249 die_find_child(sc_die, collect_variables_cb, (void *)af, &die_mem);
1250
1251 /* Find external variables */
1252 if (!af->externs)
1253 goto out;
1254 /* Don't need to search child DIE for externs. */
1255 af->child = false;
1256 die_find_child(&pf->cu_die, collect_variables_cb, (void *)af, &die_mem);
1257
1258 out:
1259 if (strlist__empty(vl->vars)) {
1260 strlist__delete(vl->vars);
1261 vl->vars = NULL;
1262 }
1263
1264 return ret;
1265 }
1266
1267 /* Find available variables at given probe point */
1268 int debuginfo__find_available_vars_at(struct debuginfo *self,
1269 struct perf_probe_event *pev,
1270 struct variable_list **vls,
1271 int max_vls, bool externs)
1272 {
1273 struct available_var_finder af = {
1274 .pf = {.pev = pev, .callback = add_available_vars},
1275 .max_vls = max_vls, .externs = externs};
1276 int ret;
1277
1278 /* Allocate result vls array */
1279 *vls = zalloc(sizeof(struct variable_list) * max_vls);
1280 if (*vls == NULL)
1281 return -ENOMEM;
1282
1283 af.vls = *vls;
1284 af.nvls = 0;
1285
1286 ret = debuginfo__find_probes(self, &af.pf);
1287 if (ret < 0) {
1288 /* Free vlist for error */
1289 while (af.nvls--) {
1290 if (af.vls[af.nvls].point.symbol)
1291 free(af.vls[af.nvls].point.symbol);
1292 if (af.vls[af.nvls].vars)
1293 strlist__delete(af.vls[af.nvls].vars);
1294 }
1295 free(af.vls);
1296 *vls = NULL;
1297 return ret;
1298 }
1299
1300 return (ret < 0) ? ret : af.nvls;
1301 }
1302
1303 /* Reverse search */
1304 int debuginfo__find_probe_point(struct debuginfo *self, unsigned long addr,
1305 struct perf_probe_point *ppt)
1306 {
1307 Dwarf_Die cudie, spdie, indie;
1308 Dwarf_Addr _addr, baseaddr;
1309 const char *fname = NULL, *func = NULL, *tmp;
1310 int baseline = 0, lineno = 0, ret = 0;
1311
1312 /* Adjust address with bias */
1313 addr += self->bias;
1314
1315 /* Find cu die */
1316 if (!dwarf_addrdie(self->dbg, (Dwarf_Addr)addr - self->bias, &cudie)) {
1317 pr_warning("Failed to find debug information for address %lx\n",
1318 addr);
1319 ret = -EINVAL;
1320 goto end;
1321 }
1322
1323 /* Find a corresponding line (filename and lineno) */
1324 cu_find_lineinfo(&cudie, addr, &fname, &lineno);
1325 /* Don't care whether it failed or not */
1326
1327 /* Find a corresponding function (name, baseline and baseaddr) */
1328 if (die_find_realfunc(&cudie, (Dwarf_Addr)addr, &spdie)) {
1329 /* Get function entry information */
1330 tmp = dwarf_diename(&spdie);
1331 if (!tmp ||
1332 dwarf_entrypc(&spdie, &baseaddr) != 0 ||
1333 dwarf_decl_line(&spdie, &baseline) != 0)
1334 goto post;
1335 func = tmp;
1336
1337 if (addr == (unsigned long)baseaddr)
1338 /* Function entry - Relative line number is 0 */
1339 lineno = baseline;
1340 else if (die_find_inlinefunc(&spdie, (Dwarf_Addr)addr,
1341 &indie)) {
1342 if (dwarf_entrypc(&indie, &_addr) == 0 &&
1343 _addr == addr)
1344 /*
1345 * addr is at an inline function entry.
1346 * In this case, lineno should be the call-site
1347 * line number.
1348 */
1349 lineno = die_get_call_lineno(&indie);
1350 else {
1351 /*
1352 * addr is in an inline function body.
1353 * Since lineno points one of the lines
1354 * of the inline function, baseline should
1355 * be the entry line of the inline function.
1356 */
1357 tmp = dwarf_diename(&indie);
1358 if (tmp &&
1359 dwarf_decl_line(&spdie, &baseline) == 0)
1360 func = tmp;
1361 }
1362 }
1363 }
1364
1365 post:
1366 /* Make a relative line number or an offset */
1367 if (lineno)
1368 ppt->line = lineno - baseline;
1369 else if (func)
1370 ppt->offset = addr - (unsigned long)baseaddr;
1371
1372 /* Duplicate strings */
1373 if (func) {
1374 ppt->function = strdup(func);
1375 if (ppt->function == NULL) {
1376 ret = -ENOMEM;
1377 goto end;
1378 }
1379 }
1380 if (fname) {
1381 ppt->file = strdup(fname);
1382 if (ppt->file == NULL) {
1383 if (ppt->function) {
1384 free(ppt->function);
1385 ppt->function = NULL;
1386 }
1387 ret = -ENOMEM;
1388 goto end;
1389 }
1390 }
1391 end:
1392 if (ret == 0 && (fname || func))
1393 ret = 1; /* Found a point */
1394 return ret;
1395 }
1396
1397 /* Add a line and store the src path */
1398 static int line_range_add_line(const char *src, unsigned int lineno,
1399 struct line_range *lr)
1400 {
1401 /* Copy source path */
1402 if (!lr->path) {
1403 lr->path = strdup(src);
1404 if (lr->path == NULL)
1405 return -ENOMEM;
1406 }
1407 return line_list__add_line(&lr->line_list, lineno);
1408 }
1409
1410 static int line_range_walk_cb(const char *fname, int lineno,
1411 Dwarf_Addr addr __used,
1412 void *data)
1413 {
1414 struct line_finder *lf = data;
1415
1416 if ((strtailcmp(fname, lf->fname) != 0) ||
1417 (lf->lno_s > lineno || lf->lno_e < lineno))
1418 return 0;
1419
1420 if (line_range_add_line(fname, lineno, lf->lr) < 0)
1421 return -EINVAL;
1422
1423 return 0;
1424 }
1425
1426 /* Find line range from its line number */
1427 static int find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf)
1428 {
1429 int ret;
1430
1431 ret = die_walk_lines(sp_die ?: &lf->cu_die, line_range_walk_cb, lf);
1432
1433 /* Update status */
1434 if (ret >= 0)
1435 if (!list_empty(&lf->lr->line_list))
1436 ret = lf->found = 1;
1437 else
1438 ret = 0; /* Lines are not found */
1439 else {
1440 free(lf->lr->path);
1441 lf->lr->path = NULL;
1442 }
1443 return ret;
1444 }
1445
1446 static int line_range_inline_cb(Dwarf_Die *in_die, void *data)
1447 {
1448 find_line_range_by_line(in_die, data);
1449
1450 /*
1451 * We have to check all instances of inlined function, because
1452 * some execution paths can be optimized out depends on the
1453 * function argument of instances
1454 */
1455 return 0;
1456 }
1457
1458 /* Search function from function name */
1459 static int line_range_search_cb(Dwarf_Die *sp_die, void *data)
1460 {
1461 struct dwarf_callback_param *param = data;
1462 struct line_finder *lf = param->data;
1463 struct line_range *lr = lf->lr;
1464
1465 /* Check declared file */
1466 if (lr->file && strtailcmp(lr->file, dwarf_decl_file(sp_die)))
1467 return DWARF_CB_OK;
1468
1469 if (dwarf_tag(sp_die) == DW_TAG_subprogram &&
1470 die_compare_name(sp_die, lr->function)) {
1471 lf->fname = dwarf_decl_file(sp_die);
1472 dwarf_decl_line(sp_die, &lr->offset);
1473 pr_debug("fname: %s, lineno:%d\n", lf->fname, lr->offset);
1474 lf->lno_s = lr->offset + lr->start;
1475 if (lf->lno_s < 0) /* Overflow */
1476 lf->lno_s = INT_MAX;
1477 lf->lno_e = lr->offset + lr->end;
1478 if (lf->lno_e < 0) /* Overflow */
1479 lf->lno_e = INT_MAX;
1480 pr_debug("New line range: %d to %d\n", lf->lno_s, lf->lno_e);
1481 lr->start = lf->lno_s;
1482 lr->end = lf->lno_e;
1483 if (dwarf_func_inline(sp_die))
1484 param->retval = die_walk_instances(sp_die,
1485 line_range_inline_cb, lf);
1486 else
1487 param->retval = find_line_range_by_line(sp_die, lf);
1488 return DWARF_CB_ABORT;
1489 }
1490 return DWARF_CB_OK;
1491 }
1492
1493 static int find_line_range_by_func(struct line_finder *lf)
1494 {
1495 struct dwarf_callback_param param = {.data = (void *)lf, .retval = 0};
1496 dwarf_getfuncs(&lf->cu_die, line_range_search_cb, &param, 0);
1497 return param.retval;
1498 }
1499
1500 int debuginfo__find_line_range(struct debuginfo *self, struct line_range *lr)
1501 {
1502 struct line_finder lf = {.lr = lr, .found = 0};
1503 int ret = 0;
1504 Dwarf_Off off = 0, noff;
1505 size_t cuhl;
1506 Dwarf_Die *diep;
1507 const char *comp_dir;
1508
1509 /* Fastpath: lookup by function name from .debug_pubnames section */
1510 if (lr->function) {
1511 struct pubname_callback_param pubname_param = {
1512 .function = lr->function, .file = lr->file,
1513 .cu_die = &lf.cu_die, .sp_die = &lf.sp_die, .found = 0};
1514 struct dwarf_callback_param line_range_param = {
1515 .data = (void *)&lf, .retval = 0};
1516
1517 dwarf_getpubnames(self->dbg, pubname_search_cb,
1518 &pubname_param, 0);
1519 if (pubname_param.found) {
1520 line_range_search_cb(&lf.sp_die, &line_range_param);
1521 if (lf.found)
1522 goto found;
1523 }
1524 }
1525
1526 /* Loop on CUs (Compilation Unit) */
1527 while (!lf.found && ret >= 0) {
1528 if (dwarf_nextcu(self->dbg, off, &noff, &cuhl,
1529 NULL, NULL, NULL) != 0)
1530 break;
1531
1532 /* Get the DIE(Debugging Information Entry) of this CU */
1533 diep = dwarf_offdie(self->dbg, off + cuhl, &lf.cu_die);
1534 if (!diep)
1535 continue;
1536
1537 /* Check if target file is included. */
1538 if (lr->file)
1539 lf.fname = cu_find_realpath(&lf.cu_die, lr->file);
1540 else
1541 lf.fname = 0;
1542
1543 if (!lr->file || lf.fname) {
1544 if (lr->function)
1545 ret = find_line_range_by_func(&lf);
1546 else {
1547 lf.lno_s = lr->start;
1548 lf.lno_e = lr->end;
1549 ret = find_line_range_by_line(NULL, &lf);
1550 }
1551 }
1552 off = noff;
1553 }
1554
1555 found:
1556 /* Store comp_dir */
1557 if (lf.found) {
1558 comp_dir = cu_get_comp_dir(&lf.cu_die);
1559 if (comp_dir) {
1560 lr->comp_dir = strdup(comp_dir);
1561 if (!lr->comp_dir)
1562 ret = -ENOMEM;
1563 }
1564 }
1565
1566 pr_debug("path: %s\n", lr->path);
1567 return (ret < 0) ? ret : lf.found;
1568 }
1569
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree