blob: e3c40a520a253c73cbad3f4e04558f006508cdb7 [file] [log] [blame]
Jiri Olsa71ad0f52012-08-07 15:20:46 +02001/*
2 * Post mortem Dwarf CFI based unwinding on top of regs and stack dumps.
3 *
4 * Lots of this code have been borrowed or heavily inspired from parts of
5 * the libunwind 0.99 code which are (amongst other contributors I may have
6 * forgotten):
7 *
8 * Copyright (C) 2002-2007 Hewlett-Packard Co
9 * Contributed by David Mosberger-Tang <davidm@hpl.hp.com>
10 *
11 * And the bugs have been added by:
12 *
13 * Copyright (C) 2010, Frederic Weisbecker <fweisbec@gmail.com>
14 * Copyright (C) 2012, Jiri Olsa <jolsa@redhat.com>
15 *
16 */
17
18#include <elf.h>
19#include <gelf.h>
20#include <fcntl.h>
21#include <string.h>
22#include <unistd.h>
23#include <sys/mman.h>
24#include <linux/list.h>
25#include <libunwind.h>
26#include <libunwind-ptrace.h>
Namhyung Kim66f066d82014-10-06 09:46:00 +090027#include "callchain.h"
Jiri Olsa71ad0f52012-08-07 15:20:46 +020028#include "thread.h"
29#include "session.h"
30#include "perf_regs.h"
31#include "unwind.h"
Masami Hiramatsu99ca4232014-01-16 09:39:49 +000032#include "symbol.h"
Jiri Olsa71ad0f52012-08-07 15:20:46 +020033#include "util.h"
Jiri Olsa84f5d362014-07-14 23:46:48 +020034#include "debug.h"
Jiri Olsa71ad0f52012-08-07 15:20:46 +020035
36extern int
37UNW_OBJ(dwarf_search_unwind_table) (unw_addr_space_t as,
38 unw_word_t ip,
39 unw_dyn_info_t *di,
40 unw_proc_info_t *pi,
41 int need_unwind_info, void *arg);
42
43#define dwarf_search_unwind_table UNW_OBJ(dwarf_search_unwind_table)
44
Jean Pihetab255e72013-09-26 12:36:38 +010045extern int
46UNW_OBJ(dwarf_find_debug_frame) (int found, unw_dyn_info_t *di_debug,
47 unw_word_t ip,
48 unw_word_t segbase,
49 const char *obj_name, unw_word_t start,
50 unw_word_t end);
51
52#define dwarf_find_debug_frame UNW_OBJ(dwarf_find_debug_frame)
53
Jiri Olsa71ad0f52012-08-07 15:20:46 +020054#define DW_EH_PE_FORMAT_MASK 0x0f /* format of the encoded value */
55#define DW_EH_PE_APPL_MASK 0x70 /* how the value is to be applied */
56
57/* Pointer-encoding formats: */
58#define DW_EH_PE_omit 0xff
59#define DW_EH_PE_ptr 0x00 /* pointer-sized unsigned value */
60#define DW_EH_PE_udata4 0x03 /* unsigned 32-bit value */
61#define DW_EH_PE_udata8 0x04 /* unsigned 64-bit value */
62#define DW_EH_PE_sdata4 0x0b /* signed 32-bit value */
63#define DW_EH_PE_sdata8 0x0c /* signed 64-bit value */
64
65/* Pointer-encoding application: */
66#define DW_EH_PE_absptr 0x00 /* absolute value */
67#define DW_EH_PE_pcrel 0x10 /* rel. to addr. of encoded value */
68
69/*
70 * The following are not documented by LSB v1.3, yet they are used by
71 * GCC, presumably they aren't documented by LSB since they aren't
72 * used on Linux:
73 */
74#define DW_EH_PE_funcrel 0x40 /* start-of-procedure-relative */
75#define DW_EH_PE_aligned 0x50 /* aligned pointer */
76
77/* Flags intentionaly not handled, since they're not needed:
78 * #define DW_EH_PE_indirect 0x80
79 * #define DW_EH_PE_uleb128 0x01
80 * #define DW_EH_PE_udata2 0x02
81 * #define DW_EH_PE_sleb128 0x09
82 * #define DW_EH_PE_sdata2 0x0a
83 * #define DW_EH_PE_textrel 0x20
84 * #define DW_EH_PE_datarel 0x30
85 */
86
87struct unwind_info {
88 struct perf_sample *sample;
89 struct machine *machine;
90 struct thread *thread;
Jiri Olsa71ad0f52012-08-07 15:20:46 +020091};
92
93#define dw_read(ptr, type, end) ({ \
94 type *__p = (type *) ptr; \
95 type __v; \
96 if ((__p + 1) > (type *) end) \
97 return -EINVAL; \
98 __v = *__p++; \
99 ptr = (typeof(ptr)) __p; \
100 __v; \
101 })
102
103static int __dw_read_encoded_value(u8 **p, u8 *end, u64 *val,
104 u8 encoding)
105{
106 u8 *cur = *p;
107 *val = 0;
108
109 switch (encoding) {
110 case DW_EH_PE_omit:
111 *val = 0;
112 goto out;
113 case DW_EH_PE_ptr:
114 *val = dw_read(cur, unsigned long, end);
115 goto out;
116 default:
117 break;
118 }
119
120 switch (encoding & DW_EH_PE_APPL_MASK) {
121 case DW_EH_PE_absptr:
122 break;
123 case DW_EH_PE_pcrel:
124 *val = (unsigned long) cur;
125 break;
126 default:
127 return -EINVAL;
128 }
129
130 if ((encoding & 0x07) == 0x00)
131 encoding |= DW_EH_PE_udata4;
132
133 switch (encoding & DW_EH_PE_FORMAT_MASK) {
134 case DW_EH_PE_sdata4:
135 *val += dw_read(cur, s32, end);
136 break;
137 case DW_EH_PE_udata4:
138 *val += dw_read(cur, u32, end);
139 break;
140 case DW_EH_PE_sdata8:
141 *val += dw_read(cur, s64, end);
142 break;
143 case DW_EH_PE_udata8:
144 *val += dw_read(cur, u64, end);
145 break;
146 default:
147 return -EINVAL;
148 }
149
150 out:
151 *p = cur;
152 return 0;
153}
154
155#define dw_read_encoded_value(ptr, end, enc) ({ \
156 u64 __v; \
157 if (__dw_read_encoded_value(&ptr, end, &__v, enc)) { \
158 return -EINVAL; \
159 } \
160 __v; \
161 })
162
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200163static u64 elf_section_offset(int fd, const char *name)
164{
165 Elf *elf;
166 GElf_Ehdr ehdr;
167 GElf_Shdr shdr;
168 u64 offset = 0;
169
170 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
171 if (elf == NULL)
172 return 0;
173
174 do {
175 if (gelf_getehdr(elf, &ehdr) == NULL)
176 break;
177
Masami Hiramatsu99ca4232014-01-16 09:39:49 +0000178 if (!elf_section_by_name(elf, &ehdr, &shdr, name, NULL))
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200179 break;
180
181 offset = shdr.sh_offset;
182 } while (0);
183
184 elf_end(elf);
185 return offset;
186}
187
Wang Nanb93b0962015-01-14 10:36:47 +0800188#ifndef NO_LIBUNWIND_DEBUG_FRAME
189static int elf_is_exec(int fd, const char *name)
190{
191 Elf *elf;
192 GElf_Ehdr ehdr;
193 int retval = 0;
194
195 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
196 if (elf == NULL)
197 return 0;
198 if (gelf_getehdr(elf, &ehdr) == NULL)
199 goto out;
200
201 retval = (ehdr.e_type == ET_EXEC);
202
203out:
204 elf_end(elf);
205 pr_debug("unwind: elf_is_exec(%s): %d\n", name, retval);
206 return retval;
207}
208#endif
209
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200210struct table_entry {
211 u32 start_ip_offset;
212 u32 fde_offset;
213};
214
215struct eh_frame_hdr {
216 unsigned char version;
217 unsigned char eh_frame_ptr_enc;
218 unsigned char fde_count_enc;
219 unsigned char table_enc;
220
221 /*
222 * The rest of the header is variable-length and consists of the
223 * following members:
224 *
225 * encoded_t eh_frame_ptr;
226 * encoded_t fde_count;
227 */
228
229 /* A single encoded pointer should not be more than 8 bytes. */
230 u64 enc[2];
231
232 /*
233 * struct {
234 * encoded_t start_ip;
235 * encoded_t fde_addr;
236 * } binary_search_table[fde_count];
237 */
238 char data[0];
239} __packed;
240
241static int unwind_spec_ehframe(struct dso *dso, struct machine *machine,
242 u64 offset, u64 *table_data, u64 *segbase,
243 u64 *fde_count)
244{
245 struct eh_frame_hdr hdr;
246 u8 *enc = (u8 *) &hdr.enc;
247 u8 *end = (u8 *) &hdr.data;
248 ssize_t r;
249
250 r = dso__data_read_offset(dso, machine, offset,
251 (u8 *) &hdr, sizeof(hdr));
252 if (r != sizeof(hdr))
253 return -EINVAL;
254
255 /* We dont need eh_frame_ptr, just skip it. */
256 dw_read_encoded_value(enc, end, hdr.eh_frame_ptr_enc);
257
258 *fde_count = dw_read_encoded_value(enc, end, hdr.fde_count_enc);
259 *segbase = offset;
260 *table_data = (enc - (u8 *) &hdr) + offset;
261 return 0;
262}
263
Jean Pihetab255e72013-09-26 12:36:38 +0100264static int read_unwind_spec_eh_frame(struct dso *dso, struct machine *machine,
265 u64 *table_data, u64 *segbase,
266 u64 *fde_count)
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200267{
268 int ret = -EINVAL, fd;
Namhyung Kimf1f13af2015-01-29 17:07:21 +0900269 u64 offset = dso->data.frame_offset;
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200270
Namhyung Kimf1f13af2015-01-29 17:07:21 +0900271 if (offset == 0) {
272 fd = dso__data_fd(dso, machine);
273 if (fd < 0)
274 return -EINVAL;
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200275
Namhyung Kimf1f13af2015-01-29 17:07:21 +0900276 /* Check the .eh_frame section for unwinding info */
277 offset = elf_section_offset(fd, ".eh_frame_hdr");
278 dso->data.frame_offset = offset;
279 }
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200280
281 if (offset)
282 ret = unwind_spec_ehframe(dso, machine, offset,
283 table_data, segbase,
284 fde_count);
285
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200286 return ret;
287}
288
Jean Pihetab255e72013-09-26 12:36:38 +0100289#ifndef NO_LIBUNWIND_DEBUG_FRAME
290static int read_unwind_spec_debug_frame(struct dso *dso,
291 struct machine *machine, u64 *offset)
292{
Namhyung Kimf1f13af2015-01-29 17:07:21 +0900293 int fd;
294 u64 ofs = dso->data.frame_offset;
Jean Pihetab255e72013-09-26 12:36:38 +0100295
Namhyung Kimf1f13af2015-01-29 17:07:21 +0900296 if (ofs == 0) {
297 fd = dso__data_fd(dso, machine);
298 if (fd < 0)
299 return -EINVAL;
Jean Pihetab255e72013-09-26 12:36:38 +0100300
Namhyung Kimf1f13af2015-01-29 17:07:21 +0900301 /* Check the .debug_frame section for unwinding info */
302 ofs = elf_section_offset(fd, ".debug_frame");
303 dso->data.frame_offset = ofs;
304 }
Jean Pihetab255e72013-09-26 12:36:38 +0100305
Namhyung Kimf1f13af2015-01-29 17:07:21 +0900306 *offset = ofs;
Jean Pihetab255e72013-09-26 12:36:38 +0100307 if (*offset)
308 return 0;
309
310 return -EINVAL;
311}
312#endif
313
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200314static struct map *find_map(unw_word_t ip, struct unwind_info *ui)
315{
316 struct addr_location al;
317
Arnaldo Carvalho de Melobb871a92014-10-23 12:50:25 -0300318 thread__find_addr_map(ui->thread, PERF_RECORD_MISC_USER,
Adrian Hunter326f59b2013-08-08 14:32:27 +0300319 MAP__FUNCTION, ip, &al);
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200320 return al.map;
321}
322
323static int
324find_proc_info(unw_addr_space_t as, unw_word_t ip, unw_proc_info_t *pi,
325 int need_unwind_info, void *arg)
326{
327 struct unwind_info *ui = arg;
328 struct map *map;
329 unw_dyn_info_t di;
330 u64 table_data, segbase, fde_count;
331
332 map = find_map(ip, ui);
333 if (!map || !map->dso)
334 return -EINVAL;
335
336 pr_debug("unwind: find_proc_info dso %s\n", map->dso->name);
337
Jean Pihetab255e72013-09-26 12:36:38 +0100338 /* Check the .eh_frame section for unwinding info */
339 if (!read_unwind_spec_eh_frame(map->dso, ui->machine,
340 &table_data, &segbase, &fde_count)) {
341 memset(&di, 0, sizeof(di));
342 di.format = UNW_INFO_FORMAT_REMOTE_TABLE;
343 di.start_ip = map->start;
344 di.end_ip = map->end;
345 di.u.rti.segbase = map->start + segbase;
346 di.u.rti.table_data = map->start + table_data;
347 di.u.rti.table_len = fde_count * sizeof(struct table_entry)
348 / sizeof(unw_word_t);
349 return dwarf_search_unwind_table(as, ip, &di, pi,
350 need_unwind_info, arg);
351 }
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200352
Jean Pihetab255e72013-09-26 12:36:38 +0100353#ifndef NO_LIBUNWIND_DEBUG_FRAME
354 /* Check the .debug_frame section for unwinding info */
355 if (!read_unwind_spec_debug_frame(map->dso, ui->machine, &segbase)) {
Wang Nanb93b0962015-01-14 10:36:47 +0800356 int fd = dso__data_fd(map->dso, ui->machine);
357 int is_exec = elf_is_exec(fd, map->dso->name);
358 unw_word_t base = is_exec ? 0 : map->start;
359
Jean Pihetab255e72013-09-26 12:36:38 +0100360 memset(&di, 0, sizeof(di));
Wang Nanb93b0962015-01-14 10:36:47 +0800361 if (dwarf_find_debug_frame(0, &di, ip, base, map->dso->name,
Jean Pihetd11416e2013-12-16 17:43:14 +0100362 map->start, map->end))
363 return dwarf_search_unwind_table(as, ip, &di, pi,
364 need_unwind_info, arg);
Jean Pihetab255e72013-09-26 12:36:38 +0100365 }
366#endif
367
368 return -EINVAL;
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200369}
370
Irina Tirdea1d037ca2012-09-11 01:15:03 +0300371static int access_fpreg(unw_addr_space_t __maybe_unused as,
372 unw_regnum_t __maybe_unused num,
373 unw_fpreg_t __maybe_unused *val,
374 int __maybe_unused __write,
375 void __maybe_unused *arg)
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200376{
377 pr_err("unwind: access_fpreg unsupported\n");
378 return -UNW_EINVAL;
379}
380
Irina Tirdea1d037ca2012-09-11 01:15:03 +0300381static int get_dyn_info_list_addr(unw_addr_space_t __maybe_unused as,
382 unw_word_t __maybe_unused *dil_addr,
383 void __maybe_unused *arg)
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200384{
385 return -UNW_ENOINFO;
386}
387
Irina Tirdea1d037ca2012-09-11 01:15:03 +0300388static int resume(unw_addr_space_t __maybe_unused as,
389 unw_cursor_t __maybe_unused *cu,
390 void __maybe_unused *arg)
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200391{
392 pr_err("unwind: resume unsupported\n");
393 return -UNW_EINVAL;
394}
395
396static int
Irina Tirdea1d037ca2012-09-11 01:15:03 +0300397get_proc_name(unw_addr_space_t __maybe_unused as,
398 unw_word_t __maybe_unused addr,
399 char __maybe_unused *bufp, size_t __maybe_unused buf_len,
400 unw_word_t __maybe_unused *offp, void __maybe_unused *arg)
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200401{
402 pr_err("unwind: get_proc_name unsupported\n");
403 return -UNW_EINVAL;
404}
405
406static int access_dso_mem(struct unwind_info *ui, unw_word_t addr,
407 unw_word_t *data)
408{
409 struct addr_location al;
410 ssize_t size;
411
Arnaldo Carvalho de Melobb871a92014-10-23 12:50:25 -0300412 thread__find_addr_map(ui->thread, PERF_RECORD_MISC_USER,
Adrian Hunter326f59b2013-08-08 14:32:27 +0300413 MAP__FUNCTION, addr, &al);
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200414 if (!al.map) {
415 pr_debug("unwind: no map for %lx\n", (unsigned long)addr);
416 return -1;
417 }
418
419 if (!al.map->dso)
420 return -1;
421
422 size = dso__data_read_addr(al.map->dso, al.map, ui->machine,
423 addr, (u8 *) data, sizeof(*data));
424
425 return !(size == sizeof(*data));
426}
427
Irina Tirdea1d037ca2012-09-11 01:15:03 +0300428static int access_mem(unw_addr_space_t __maybe_unused as,
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200429 unw_word_t addr, unw_word_t *valp,
430 int __write, void *arg)
431{
432 struct unwind_info *ui = arg;
433 struct stack_dump *stack = &ui->sample->user_stack;
Jiri Olsac9b951c2014-01-07 13:47:29 +0100434 u64 start, end;
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200435 int offset;
436 int ret;
437
438 /* Don't support write, probably not needed. */
439 if (__write || !stack || !ui->sample->user_regs.regs) {
440 *valp = 0;
441 return 0;
442 }
443
Jiri Olsac9b951c2014-01-07 13:47:29 +0100444 ret = perf_reg_value(&start, &ui->sample->user_regs, PERF_REG_SP);
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200445 if (ret)
446 return ret;
447
448 end = start + stack->size;
449
450 /* Check overflow. */
451 if (addr + sizeof(unw_word_t) < addr)
452 return -EINVAL;
453
454 if (addr < start || addr + sizeof(unw_word_t) >= end) {
455 ret = access_dso_mem(ui, addr, valp);
456 if (ret) {
Jiri Olsac9b951c2014-01-07 13:47:29 +0100457 pr_debug("unwind: access_mem %p not inside range"
458 " 0x%" PRIx64 "-0x%" PRIx64 "\n",
459 (void *) addr, start, end);
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200460 *valp = 0;
461 return ret;
462 }
463 return 0;
464 }
465
466 offset = addr - start;
467 *valp = *(unw_word_t *)&stack->data[offset];
Jiri Olsac9b951c2014-01-07 13:47:29 +0100468 pr_debug("unwind: access_mem addr %p val %lx, offset %d\n",
469 (void *) addr, (unsigned long)*valp, offset);
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200470 return 0;
471}
472
Irina Tirdea1d037ca2012-09-11 01:15:03 +0300473static int access_reg(unw_addr_space_t __maybe_unused as,
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200474 unw_regnum_t regnum, unw_word_t *valp,
475 int __write, void *arg)
476{
477 struct unwind_info *ui = arg;
478 int id, ret;
Jiri Olsac9b951c2014-01-07 13:47:29 +0100479 u64 val;
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200480
481 /* Don't support write, I suspect we don't need it. */
482 if (__write) {
483 pr_err("unwind: access_reg w %d\n", regnum);
484 return 0;
485 }
486
487 if (!ui->sample->user_regs.regs) {
488 *valp = 0;
489 return 0;
490 }
491
Jiri Olsaea3da692014-01-07 13:47:27 +0100492 id = libunwind__arch_reg_id(regnum);
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200493 if (id < 0)
494 return -EINVAL;
495
Jiri Olsac9b951c2014-01-07 13:47:29 +0100496 ret = perf_reg_value(&val, &ui->sample->user_regs, id);
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200497 if (ret) {
498 pr_err("unwind: can't read reg %d\n", regnum);
499 return ret;
500 }
501
Jiri Olsac9b951c2014-01-07 13:47:29 +0100502 *valp = (unw_word_t) val;
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200503 pr_debug("unwind: reg %d, val %lx\n", regnum, (unsigned long)*valp);
504 return 0;
505}
506
Irina Tirdea1d037ca2012-09-11 01:15:03 +0300507static void put_unwind_info(unw_addr_space_t __maybe_unused as,
508 unw_proc_info_t *pi __maybe_unused,
509 void *arg __maybe_unused)
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200510{
511 pr_debug("unwind: put_unwind_info called\n");
512}
513
Arnaldo Carvalho de Melobb871a92014-10-23 12:50:25 -0300514static int entry(u64 ip, struct thread *thread,
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200515 unwind_entry_cb_t cb, void *arg)
516{
517 struct unwind_entry e;
518 struct addr_location al;
519
Arnaldo Carvalho de Melobb871a92014-10-23 12:50:25 -0300520 thread__find_addr_location(thread, PERF_RECORD_MISC_USER,
Adrian Hunter61710bd2013-08-08 14:32:26 +0300521 MAP__FUNCTION, ip, &al);
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200522
523 e.ip = ip;
524 e.map = al.map;
525 e.sym = al.sym;
526
527 pr_debug("unwind: %s:ip = 0x%" PRIx64 " (0x%" PRIx64 ")\n",
528 al.sym ? al.sym->name : "''",
529 ip,
530 al.map ? al.map->map_ip(al.map, ip) : (u64) 0);
531
532 return cb(&e, arg);
533}
534
535static void display_error(int err)
536{
537 switch (err) {
538 case UNW_EINVAL:
539 pr_err("unwind: Only supports local.\n");
540 break;
541 case UNW_EUNSPEC:
542 pr_err("unwind: Unspecified error.\n");
543 break;
544 case UNW_EBADREG:
545 pr_err("unwind: Register unavailable.\n");
546 break;
547 default:
548 break;
549 }
550}
551
552static unw_accessors_t accessors = {
553 .find_proc_info = find_proc_info,
554 .put_unwind_info = put_unwind_info,
555 .get_dyn_info_list_addr = get_dyn_info_list_addr,
556 .access_mem = access_mem,
557 .access_reg = access_reg,
558 .access_fpreg = access_fpreg,
559 .resume = resume,
560 .get_proc_name = get_proc_name,
561};
562
Namhyung Kim66f066d82014-10-06 09:46:00 +0900563int unwind__prepare_access(struct thread *thread)
564{
565 unw_addr_space_t addr_space;
566
567 if (callchain_param.record_mode != CALLCHAIN_DWARF)
568 return 0;
569
570 addr_space = unw_create_addr_space(&accessors, 0);
571 if (!addr_space) {
572 pr_err("unwind: Can't create unwind address space.\n");
573 return -ENOMEM;
574 }
575
Namhyung Kim380b5142014-10-06 09:46:01 +0900576 unw_set_caching_policy(addr_space, UNW_CACHE_GLOBAL);
Namhyung Kim66f066d82014-10-06 09:46:00 +0900577 thread__set_priv(thread, addr_space);
578
579 return 0;
580}
581
Namhyung Kim380b5142014-10-06 09:46:01 +0900582void unwind__flush_access(struct thread *thread)
583{
584 unw_addr_space_t addr_space;
585
586 if (callchain_param.record_mode != CALLCHAIN_DWARF)
587 return;
588
589 addr_space = thread__priv(thread);
590 unw_flush_cache(addr_space, 0, 0);
591}
592
Namhyung Kim66f066d82014-10-06 09:46:00 +0900593void unwind__finish_access(struct thread *thread)
594{
595 unw_addr_space_t addr_space;
596
597 if (callchain_param.record_mode != CALLCHAIN_DWARF)
598 return;
599
600 addr_space = thread__priv(thread);
601 unw_destroy_addr_space(addr_space);
602}
603
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200604static int get_entries(struct unwind_info *ui, unwind_entry_cb_t cb,
Arnaldo Carvalho de Melo37676af2013-11-13 17:40:36 -0300605 void *arg, int max_stack)
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200606{
607 unw_addr_space_t addr_space;
608 unw_cursor_t c;
609 int ret;
610
Namhyung Kim66f066d82014-10-06 09:46:00 +0900611 addr_space = thread__priv(ui->thread);
612 if (addr_space == NULL)
613 return -1;
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200614
615 ret = unw_init_remote(&c, addr_space, ui);
616 if (ret)
617 display_error(ret);
618
Arnaldo Carvalho de Melo37676af2013-11-13 17:40:36 -0300619 while (!ret && (unw_step(&c) > 0) && max_stack--) {
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200620 unw_word_t ip;
621
622 unw_get_reg(&c, UNW_REG_IP, &ip);
Arnaldo Carvalho de Melobb871a92014-10-23 12:50:25 -0300623 ret = ip ? entry(ip, ui->thread, cb, arg) : 0;
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200624 }
625
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200626 return ret;
627}
628
629int unwind__get_entries(unwind_entry_cb_t cb, void *arg,
Arnaldo Carvalho de Melodd8c17a2014-10-23 16:42:19 -0300630 struct thread *thread,
Jiri Olsa352ea452014-01-07 13:47:25 +0100631 struct perf_sample *data, int max_stack)
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200632{
Jiri Olsac9b951c2014-01-07 13:47:29 +0100633 u64 ip;
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200634 struct unwind_info ui = {
635 .sample = data,
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200636 .thread = thread,
Arnaldo Carvalho de Melodd8c17a2014-10-23 16:42:19 -0300637 .machine = thread->mg->machine,
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200638 };
639 int ret;
640
641 if (!data->user_regs.regs)
642 return -EINVAL;
643
Jiri Olsac9b951c2014-01-07 13:47:29 +0100644 ret = perf_reg_value(&ip, &data->user_regs, PERF_REG_IP);
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200645 if (ret)
646 return ret;
647
Arnaldo Carvalho de Melobb871a92014-10-23 12:50:25 -0300648 ret = entry(ip, thread, cb, arg);
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200649 if (ret)
650 return -ENOMEM;
651
Jiri Olsab42dc32d2014-01-07 13:47:23 +0100652 return --max_stack > 0 ? get_entries(&ui, cb, arg, max_stack) : 0;
Jiri Olsa71ad0f52012-08-07 15:20:46 +0200653}