1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * probe-event.c : perf-probe definition to probe_events format converter
4 *
5 * Written by Masami Hiramatsu <mhiramat@redhat.com>
6 */
7
8 #include <inttypes.h>
9 #include <sys/utsname.h>
10 #include <sys/types.h>
11 #include <sys/stat.h>
12 #include <fcntl.h>
13 #include <errno.h>
14 #include <stdio.h>
15 #include <unistd.h>
16 #include <stdlib.h>
17 #include <string.h>
18 #include <stdarg.h>
19 #include <limits.h>
20 #include <elf.h>
21
22 #include "build-id.h"
23 #include "event.h"
24 #include "namespaces.h"
25 #include "strlist.h"
26 #include "strfilter.h"
27 #include "debug.h"
28 #include "dso.h"
29 #include "color.h"
30 #include "map.h"
31 #include "maps.h"
32 #include "symbol.h"
33 #include <api/fs/fs.h>
34 #include "trace-event.h" /* For __maybe_unused */
35 #include "probe-event.h"
36 #include "probe-finder.h"
37 #include "probe-file.h"
38 #include "session.h"
39 #include "string2.h"
40 #include "strbuf.h"
41
42 #include <subcmd/pager.h>
43 #include <linux/ctype.h>
44 #include <linux/zalloc.h>
45
46 #ifdef HAVE_DEBUGINFOD_SUPPORT
47 #include <elfutils/debuginfod.h>
48 #endif
49
50 #define PERFPROBE_GROUP "probe"
51
52 bool probe_event_dry_run; /* Dry run flag */
53 struct probe_conf probe_conf = { .magic_num = DEFAULT_PROBE_MAGIC_NUM };
54
55 #define semantic_error(msg ...) pr_err("Semantic error :" msg)
56
e_snprintf(char * str,size_t size,const char * format,...)57 int e_snprintf(char *str, size_t size, const char *format, ...)
58 {
59 int ret;
60 va_list ap;
61 va_start(ap, format);
62 ret = vsnprintf(str, size, format, ap);
63 va_end(ap);
64 if (ret >= (int)size)
65 ret = -E2BIG;
66 return ret;
67 }
68
69 static struct machine *host_machine;
70
71 /* Initialize symbol maps and path of vmlinux/modules */
init_probe_symbol_maps(bool user_only)72 int init_probe_symbol_maps(bool user_only)
73 {
74 int ret;
75
76 symbol_conf.sort_by_name = true;
77 symbol_conf.allow_aliases = true;
78 ret = symbol__init(NULL);
79 if (ret < 0) {
80 pr_debug("Failed to init symbol map.\n");
81 goto out;
82 }
83
84 if (host_machine || user_only) /* already initialized */
85 return 0;
86
87 if (symbol_conf.vmlinux_name)
88 pr_debug("Use vmlinux: %s\n", symbol_conf.vmlinux_name);
89
90 host_machine = machine__new_host();
91 if (!host_machine) {
92 pr_debug("machine__new_host() failed.\n");
93 symbol__exit();
94 ret = -1;
95 }
96 out:
97 if (ret < 0)
98 pr_warning("Failed to init vmlinux path.\n");
99 return ret;
100 }
101
exit_probe_symbol_maps(void)102 void exit_probe_symbol_maps(void)
103 {
104 machine__delete(host_machine);
105 host_machine = NULL;
106 symbol__exit();
107 }
108
kernel_get_ref_reloc_sym(struct map ** pmap)109 static struct ref_reloc_sym *kernel_get_ref_reloc_sym(struct map **pmap)
110 {
111 struct kmap *kmap;
112 struct map *map = machine__kernel_map(host_machine);
113
114 if (map__load(map) < 0)
115 return NULL;
116
117 kmap = map__kmap(map);
118 if (!kmap)
119 return NULL;
120
121 if (pmap)
122 *pmap = map;
123
124 return kmap->ref_reloc_sym;
125 }
126
kernel_get_symbol_address_by_name(const char * name,u64 * addr,bool reloc,bool reladdr)127 static int kernel_get_symbol_address_by_name(const char *name, u64 *addr,
128 bool reloc, bool reladdr)
129 {
130 struct ref_reloc_sym *reloc_sym;
131 struct symbol *sym;
132 struct map *map;
133
134 /* ref_reloc_sym is just a label. Need a special fix*/
135 reloc_sym = kernel_get_ref_reloc_sym(&map);
136 if (reloc_sym && strcmp(name, reloc_sym->name) == 0)
137 *addr = (!map->reloc || reloc) ? reloc_sym->addr :
138 reloc_sym->unrelocated_addr;
139 else {
140 sym = machine__find_kernel_symbol_by_name(host_machine, name, &map);
141 if (!sym)
142 return -ENOENT;
143 *addr = map->unmap_ip(map, sym->start) -
144 ((reloc) ? 0 : map->reloc) -
145 ((reladdr) ? map->start : 0);
146 }
147 return 0;
148 }
149
kernel_get_module_map(const char * module)150 static struct map *kernel_get_module_map(const char *module)
151 {
152 struct maps *maps = machine__kernel_maps(host_machine);
153 struct map *pos;
154
155 /* A file path -- this is an offline module */
156 if (module && strchr(module, '/'))
157 return dso__new_map(module);
158
159 if (!module) {
160 pos = machine__kernel_map(host_machine);
161 return map__get(pos);
162 }
163
164 maps__for_each_entry(maps, pos) {
165 /* short_name is "[module]" */
166 if (strncmp(pos->dso->short_name + 1, module,
167 pos->dso->short_name_len - 2) == 0 &&
168 module[pos->dso->short_name_len - 2] == '\0') {
169 return map__get(pos);
170 }
171 }
172 return NULL;
173 }
174
get_target_map(const char * target,struct nsinfo * nsi,bool user)175 struct map *get_target_map(const char *target, struct nsinfo *nsi, bool user)
176 {
177 /* Init maps of given executable or kernel */
178 if (user) {
179 struct map *map;
180
181 map = dso__new_map(target);
182 if (map && map->dso) {
183 nsinfo__put(map->dso->nsinfo);
184 map->dso->nsinfo = nsinfo__get(nsi);
185 }
186 return map;
187 } else {
188 return kernel_get_module_map(target);
189 }
190 }
191
convert_exec_to_group(const char * exec,char ** result)192 static int convert_exec_to_group(const char *exec, char **result)
193 {
194 char *ptr1, *ptr2, *exec_copy;
195 char buf[64];
196 int ret;
197
198 exec_copy = strdup(exec);
199 if (!exec_copy)
200 return -ENOMEM;
201
202 ptr1 = basename(exec_copy);
203 if (!ptr1) {
204 ret = -EINVAL;
205 goto out;
206 }
207
208 for (ptr2 = ptr1; *ptr2 != '\0'; ptr2++) {
209 if (!isalnum(*ptr2) && *ptr2 != '_') {
210 *ptr2 = '\0';
211 break;
212 }
213 }
214
215 ret = e_snprintf(buf, 64, "%s_%s", PERFPROBE_GROUP, ptr1);
216 if (ret < 0)
217 goto out;
218
219 *result = strdup(buf);
220 ret = *result ? 0 : -ENOMEM;
221
222 out:
223 free(exec_copy);
224 return ret;
225 }
226
clear_perf_probe_point(struct perf_probe_point * pp)227 static void clear_perf_probe_point(struct perf_probe_point *pp)
228 {
229 zfree(&pp->file);
230 zfree(&pp->function);
231 zfree(&pp->lazy_line);
232 }
233
clear_probe_trace_events(struct probe_trace_event * tevs,int ntevs)234 static void clear_probe_trace_events(struct probe_trace_event *tevs, int ntevs)
235 {
236 int i;
237
238 for (i = 0; i < ntevs; i++)
239 clear_probe_trace_event(tevs + i);
240 }
241
242 static bool kprobe_blacklist__listed(u64 address);
kprobe_warn_out_range(const char * symbol,u64 address)243 static bool kprobe_warn_out_range(const char *symbol, u64 address)
244 {
245 struct map *map;
246 bool ret = false;
247
248 map = kernel_get_module_map(NULL);
249 if (map) {
250 ret = address <= map->start || map->end < address;
251 if (ret)
252 pr_warning("%s is out of .text, skip it.\n", symbol);
253 map__put(map);
254 }
255 if (!ret && kprobe_blacklist__listed(address)) {
256 pr_warning("%s is blacklisted function, skip it.\n", symbol);
257 ret = true;
258 }
259
260 return ret;
261 }
262
263 /*
264 * @module can be module name of module file path. In case of path,
265 * inspect elf and find out what is actual module name.
266 * Caller has to free mod_name after using it.
267 */
find_module_name(const char * module)268 static char *find_module_name(const char *module)
269 {
270 int fd;
271 Elf *elf;
272 GElf_Ehdr ehdr;
273 GElf_Shdr shdr;
274 Elf_Data *data;
275 Elf_Scn *sec;
276 char *mod_name = NULL;
277 int name_offset;
278
279 fd = open(module, O_RDONLY);
280 if (fd < 0)
281 return NULL;
282
283 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
284 if (elf == NULL)
285 goto elf_err;
286
287 if (gelf_getehdr(elf, &ehdr) == NULL)
288 goto ret_err;
289
290 sec = elf_section_by_name(elf, &ehdr, &shdr,
291 ".gnu.linkonce.this_module", NULL);
292 if (!sec)
293 goto ret_err;
294
295 data = elf_getdata(sec, NULL);
296 if (!data || !data->d_buf)
297 goto ret_err;
298
299 /*
300 * NOTE:
301 * '.gnu.linkonce.this_module' section of kernel module elf directly
302 * maps to 'struct module' from linux/module.h. This section contains
303 * actual module name which will be used by kernel after loading it.
304 * But, we cannot use 'struct module' here since linux/module.h is not
305 * exposed to user-space. Offset of 'name' has remained same from long
306 * time, so hardcoding it here.
307 */
308 if (ehdr.e_ident[EI_CLASS] == ELFCLASS32)
309 name_offset = 12;
310 else /* expect ELFCLASS64 by default */
311 name_offset = 24;
312
313 mod_name = strdup((char *)data->d_buf + name_offset);
314
315 ret_err:
316 elf_end(elf);
317 elf_err:
318 close(fd);
319 return mod_name;
320 }
321
322 #ifdef HAVE_DWARF_SUPPORT
323
kernel_get_module_dso(const char * module,struct dso ** pdso)324 static int kernel_get_module_dso(const char *module, struct dso **pdso)
325 {
326 struct dso *dso;
327 struct map *map;
328 const char *vmlinux_name;
329 int ret = 0;
330
331 if (module) {
332 char module_name[128];
333
334 snprintf(module_name, sizeof(module_name), "[%s]", module);
335 map = maps__find_by_name(&host_machine->kmaps, module_name);
336 if (map) {
337 dso = map->dso;
338 goto found;
339 }
340 pr_debug("Failed to find module %s.\n", module);
341 return -ENOENT;
342 }
343
344 map = machine__kernel_map(host_machine);
345 dso = map->dso;
346 if (!dso->has_build_id)
347 dso__read_running_kernel_build_id(dso, host_machine);
348
349 vmlinux_name = symbol_conf.vmlinux_name;
350 dso->load_errno = 0;
351 if (vmlinux_name)
352 ret = dso__load_vmlinux(dso, map, vmlinux_name, false);
353 else
354 ret = dso__load_vmlinux_path(dso, map);
355 found:
356 *pdso = dso;
357 return ret;
358 }
359
360 /*
361 * Some binaries like glibc have special symbols which are on the symbol
362 * table, but not in the debuginfo. If we can find the address of the
363 * symbol from map, we can translate the address back to the probe point.
364 */
find_alternative_probe_point(struct debuginfo * dinfo,struct perf_probe_point * pp,struct perf_probe_point * result,const char * target,struct nsinfo * nsi,bool uprobes)365 static int find_alternative_probe_point(struct debuginfo *dinfo,
366 struct perf_probe_point *pp,
367 struct perf_probe_point *result,
368 const char *target, struct nsinfo *nsi,
369 bool uprobes)
370 {
371 struct map *map = NULL;
372 struct symbol *sym;
373 u64 address = 0;
374 int ret = -ENOENT;
375
376 /* This can work only for function-name based one */
377 if (!pp->function || pp->file)
378 return -ENOTSUP;
379
380 map = get_target_map(target, nsi, uprobes);
381 if (!map)
382 return -EINVAL;
383
384 /* Find the address of given function */
385 map__for_each_symbol_by_name(map, pp->function, sym) {
386 if (uprobes) {
387 address = sym->start;
388 if (sym->type == STT_GNU_IFUNC)
389 pr_warning("Warning: The probe function (%s) is a GNU indirect function.\n"
390 "Consider identifying the final function used at run time and set the probe directly on that.\n",
391 pp->function);
392 } else
393 address = map->unmap_ip(map, sym->start) - map->reloc;
394 break;
395 }
396 if (!address) {
397 ret = -ENOENT;
398 goto out;
399 }
400 pr_debug("Symbol %s address found : %" PRIx64 "\n",
401 pp->function, address);
402
403 ret = debuginfo__find_probe_point(dinfo, address, result);
404 if (ret <= 0)
405 ret = (!ret) ? -ENOENT : ret;
406 else {
407 result->offset += pp->offset;
408 result->line += pp->line;
409 result->retprobe = pp->retprobe;
410 ret = 0;
411 }
412
413 out:
414 map__put(map);
415 return ret;
416
417 }
418
get_alternative_probe_event(struct debuginfo * dinfo,struct perf_probe_event * pev,struct perf_probe_point * tmp)419 static int get_alternative_probe_event(struct debuginfo *dinfo,
420 struct perf_probe_event *pev,
421 struct perf_probe_point *tmp)
422 {
423 int ret;
424
425 memcpy(tmp, &pev->point, sizeof(*tmp));
426 memset(&pev->point, 0, sizeof(pev->point));
427 ret = find_alternative_probe_point(dinfo, tmp, &pev->point, pev->target,
428 pev->nsi, pev->uprobes);
429 if (ret < 0)
430 memcpy(&pev->point, tmp, sizeof(*tmp));
431
432 return ret;
433 }
434
get_alternative_line_range(struct debuginfo * dinfo,struct line_range * lr,const char * target,bool user)435 static int get_alternative_line_range(struct debuginfo *dinfo,
436 struct line_range *lr,
437 const char *target, bool user)
438 {
439 struct perf_probe_point pp = { .function = lr->function,
440 .file = lr->file,
441 .line = lr->start };
442 struct perf_probe_point result;
443 int ret, len = 0;
444
445 memset(&result, 0, sizeof(result));
446
447 if (lr->end != INT_MAX)
448 len = lr->end - lr->start;
449 ret = find_alternative_probe_point(dinfo, &pp, &result,
450 target, NULL, user);
451 if (!ret) {
452 lr->function = result.function;
453 lr->file = result.file;
454 lr->start = result.line;
455 if (lr->end != INT_MAX)
456 lr->end = lr->start + len;
457 clear_perf_probe_point(&pp);
458 }
459 return ret;
460 }
461
462 #ifdef HAVE_DEBUGINFOD_SUPPORT
open_from_debuginfod(struct dso * dso,struct nsinfo * nsi,bool silent)463 static struct debuginfo *open_from_debuginfod(struct dso *dso, struct nsinfo *nsi,
464 bool silent)
465 {
466 debuginfod_client *c = debuginfod_begin();
467 char sbuild_id[SBUILD_ID_SIZE + 1];
468 struct debuginfo *ret = NULL;
469 struct nscookie nsc;
470 char *path;
471 int fd;
472
473 if (!c)
474 return NULL;
475
476 build_id__sprintf(&dso->bid, sbuild_id);
477 fd = debuginfod_find_debuginfo(c, (const unsigned char *)sbuild_id,
478 0, &path);
479 if (fd >= 0)
480 close(fd);
481 debuginfod_end(c);
482 if (fd < 0) {
483 if (!silent)
484 pr_debug("Failed to find debuginfo in debuginfod.\n");
485 return NULL;
486 }
487 if (!silent)
488 pr_debug("Load debuginfo from debuginfod (%s)\n", path);
489
490 nsinfo__mountns_enter(nsi, &nsc);
491 ret = debuginfo__new((const char *)path);
492 nsinfo__mountns_exit(&nsc);
493 return ret;
494 }
495 #else
496 static inline
open_from_debuginfod(struct dso * dso __maybe_unused,struct nsinfo * nsi __maybe_unused,bool silent __maybe_unused)497 struct debuginfo *open_from_debuginfod(struct dso *dso __maybe_unused,
498 struct nsinfo *nsi __maybe_unused,
499 bool silent __maybe_unused)
500 {
501 return NULL;
502 }
503 #endif
504
505 /* Open new debuginfo of given module */
open_debuginfo(const char * module,struct nsinfo * nsi,bool silent)506 static struct debuginfo *open_debuginfo(const char *module, struct nsinfo *nsi,
507 bool silent)
508 {
509 const char *path = module;
510 char reason[STRERR_BUFSIZE];
511 struct debuginfo *ret = NULL;
512 struct dso *dso = NULL;
513 struct nscookie nsc;
514 int err;
515
516 if (!module || !strchr(module, '/')) {
517 err = kernel_get_module_dso(module, &dso);
518 if (err < 0) {
519 if (!dso || dso->load_errno == 0) {
520 if (!str_error_r(-err, reason, STRERR_BUFSIZE))
521 strcpy(reason, "(unknown)");
522 } else
523 dso__strerror_load(dso, reason, STRERR_BUFSIZE);
524 if (dso)
525 ret = open_from_debuginfod(dso, nsi, silent);
526 if (ret)
527 return ret;
528 if (!silent) {
529 if (module)
530 pr_err("Module %s is not loaded, please specify its full path name.\n", module);
531 else
532 pr_err("Failed to find the path for the kernel: %s\n", reason);
533 }
534 return NULL;
535 }
536 path = dso->long_name;
537 }
538 nsinfo__mountns_enter(nsi, &nsc);
539 ret = debuginfo__new(path);
540 if (!ret && !silent) {
541 pr_warning("The %s file has no debug information.\n", path);
542 if (!module || !strtailcmp(path, ".ko"))
543 pr_warning("Rebuild with CONFIG_DEBUG_INFO=y, ");
544 else
545 pr_warning("Rebuild with -g, ");
546 pr_warning("or install an appropriate debuginfo package.\n");
547 }
548 nsinfo__mountns_exit(&nsc);
549 return ret;
550 }
551
552 /* For caching the last debuginfo */
553 static struct debuginfo *debuginfo_cache;
554 static char *debuginfo_cache_path;
555
debuginfo_cache__open(const char * module,bool silent)556 static struct debuginfo *debuginfo_cache__open(const char *module, bool silent)
557 {
558 const char *path = module;
559
560 /* If the module is NULL, it should be the kernel. */
561 if (!module)
562 path = "kernel";
563
564 if (debuginfo_cache_path && !strcmp(debuginfo_cache_path, path))
565 goto out;
566
567 /* Copy module path */
568 free(debuginfo_cache_path);
569 debuginfo_cache_path = strdup(path);
570 if (!debuginfo_cache_path) {
571 debuginfo__delete(debuginfo_cache);
572 debuginfo_cache = NULL;
573 goto out;
574 }
575
576 debuginfo_cache = open_debuginfo(module, NULL, silent);
577 if (!debuginfo_cache)
578 zfree(&debuginfo_cache_path);
579 out:
580 return debuginfo_cache;
581 }
582
debuginfo_cache__exit(void)583 static void debuginfo_cache__exit(void)
584 {
585 debuginfo__delete(debuginfo_cache);
586 debuginfo_cache = NULL;
587 zfree(&debuginfo_cache_path);
588 }
589
590
get_text_start_address(const char * exec,u64 * address,struct nsinfo * nsi)591 static int get_text_start_address(const char *exec, u64 *address,
592 struct nsinfo *nsi)
593 {
594 Elf *elf;
595 GElf_Ehdr ehdr;
596 GElf_Shdr shdr;
597 int fd, ret = -ENOENT;
598 struct nscookie nsc;
599
600 nsinfo__mountns_enter(nsi, &nsc);
601 fd = open(exec, O_RDONLY);
602 nsinfo__mountns_exit(&nsc);
603 if (fd < 0)
604 return -errno;
605
606 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
607 if (elf == NULL) {
608 ret = -EINVAL;
609 goto out_close;
610 }
611
612 if (gelf_getehdr(elf, &ehdr) == NULL)
613 goto out;
614
615 if (!elf_section_by_name(elf, &ehdr, &shdr, ".text", NULL))
616 goto out;
617
618 *address = shdr.sh_addr - shdr.sh_offset;
619 ret = 0;
620 out:
621 elf_end(elf);
622 out_close:
623 close(fd);
624
625 return ret;
626 }
627
628 /*
629 * Convert trace point to probe point with debuginfo
630 */
find_perf_probe_point_from_dwarf(struct probe_trace_point * tp,struct perf_probe_point * pp,bool is_kprobe)631 static int find_perf_probe_point_from_dwarf(struct probe_trace_point *tp,
632 struct perf_probe_point *pp,
633 bool is_kprobe)
634 {
635 struct debuginfo *dinfo = NULL;
636 u64 stext = 0;
637 u64 addr = tp->address;
638 int ret = -ENOENT;
639
640 /* convert the address to dwarf address */
641 if (!is_kprobe) {
642 if (!addr) {
643 ret = -EINVAL;
644 goto error;
645 }
646 ret = get_text_start_address(tp->module, &stext, NULL);
647 if (ret < 0)
648 goto error;
649 addr += stext;
650 } else if (tp->symbol) {
651 /* If the module is given, this returns relative address */
652 ret = kernel_get_symbol_address_by_name(tp->symbol, &addr,
653 false, !!tp->module);
654 if (ret != 0)
655 goto error;
656 addr += tp->offset;
657 }
658
659 pr_debug("try to find information at %" PRIx64 " in %s\n", addr,
660 tp->module ? : "kernel");
661
662 dinfo = debuginfo_cache__open(tp->module, verbose <= 0);
663 if (dinfo)
664 ret = debuginfo__find_probe_point(dinfo, addr, pp);
665 else
666 ret = -ENOENT;
667
668 if (ret > 0) {
669 pp->retprobe = tp->retprobe;
670 return 0;
671 }
672 error:
673 pr_debug("Failed to find corresponding probes from debuginfo.\n");
674 return ret ? : -ENOENT;
675 }
676
677 /* Adjust symbol name and address */
post_process_probe_trace_point(struct probe_trace_point * tp,struct map * map,u64 offs)678 static int post_process_probe_trace_point(struct probe_trace_point *tp,
679 struct map *map, u64 offs)
680 {
681 struct symbol *sym;
682 u64 addr = tp->address - offs;
683
684 sym = map__find_symbol(map, addr);
685 if (!sym) {
686 /*
687 * If the address is in the inittext section, map can not
688 * find it. Ignore it if we are probing offline kernel.
689 */
690 return (symbol_conf.ignore_vmlinux_buildid) ? 0 : -ENOENT;
691 }
692
693 if (strcmp(sym->name, tp->symbol)) {
694 /* If we have no realname, use symbol for it */
695 if (!tp->realname)
696 tp->realname = tp->symbol;
697 else
698 free(tp->symbol);
699 tp->symbol = strdup(sym->name);
700 if (!tp->symbol)
701 return -ENOMEM;
702 }
703 tp->offset = addr - sym->start;
704 tp->address -= offs;
705
706 return 0;
707 }
708
709 /*
710 * Rename DWARF symbols to ELF symbols -- gcc sometimes optimizes functions
711 * and generate new symbols with suffixes such as .constprop.N or .isra.N
712 * etc. Since those symbols are not recorded in DWARF, we have to find
713 * correct generated symbols from offline ELF binary.
714 * For online kernel or uprobes we don't need this because those are
715 * rebased on _text, or already a section relative address.
716 */
717 static int
post_process_offline_probe_trace_events(struct probe_trace_event * tevs,int ntevs,const char * pathname)718 post_process_offline_probe_trace_events(struct probe_trace_event *tevs,
719 int ntevs, const char *pathname)
720 {
721 struct map *map;
722 u64 stext = 0;
723 int i, ret = 0;
724
725 /* Prepare a map for offline binary */
726 map = dso__new_map(pathname);
727 if (!map || get_text_start_address(pathname, &stext, NULL) < 0) {
728 pr_warning("Failed to get ELF symbols for %s\n", pathname);
729 return -EINVAL;
730 }
731
732 for (i = 0; i < ntevs; i++) {
733 ret = post_process_probe_trace_point(&tevs[i].point,
734 map, stext);
735 if (ret < 0)
736 break;
737 }
738 map__put(map);
739
740 return ret;
741 }
742
add_exec_to_probe_trace_events(struct probe_trace_event * tevs,int ntevs,const char * exec,struct nsinfo * nsi)743 static int add_exec_to_probe_trace_events(struct probe_trace_event *tevs,
744 int ntevs, const char *exec,
745 struct nsinfo *nsi)
746 {
747 int i, ret = 0;
748 u64 stext = 0;
749
750 if (!exec)
751 return 0;
752
753 ret = get_text_start_address(exec, &stext, nsi);
754 if (ret < 0)
755 return ret;
756
757 for (i = 0; i < ntevs && ret >= 0; i++) {
758 /* point.address is the address of point.symbol + point.offset */
759 tevs[i].point.address -= stext;
760 tevs[i].point.module = strdup(exec);
761 if (!tevs[i].point.module) {
762 ret = -ENOMEM;
763 break;
764 }
765 tevs[i].uprobes = true;
766 }
767
768 return ret;
769 }
770
771 static int
post_process_module_probe_trace_events(struct probe_trace_event * tevs,int ntevs,const char * module,struct debuginfo * dinfo)772 post_process_module_probe_trace_events(struct probe_trace_event *tevs,
773 int ntevs, const char *module,
774 struct debuginfo *dinfo)
775 {
776 Dwarf_Addr text_offs = 0;
777 int i, ret = 0;
778 char *mod_name = NULL;
779 struct map *map;
780
781 if (!module)
782 return 0;
783
784 map = get_target_map(module, NULL, false);
785 if (!map || debuginfo__get_text_offset(dinfo, &text_offs, true) < 0) {
786 pr_warning("Failed to get ELF symbols for %s\n", module);
787 return -EINVAL;
788 }
789
790 mod_name = find_module_name(module);
791 for (i = 0; i < ntevs; i++) {
792 ret = post_process_probe_trace_point(&tevs[i].point,
793 map, text_offs);
794 if (ret < 0)
795 break;
796 tevs[i].point.module =
797 strdup(mod_name ? mod_name : module);
798 if (!tevs[i].point.module) {
799 ret = -ENOMEM;
800 break;
801 }
802 }
803
804 free(mod_name);
805 map__put(map);
806
807 return ret;
808 }
809
810 static int
post_process_kernel_probe_trace_events(struct probe_trace_event * tevs,int ntevs)811 post_process_kernel_probe_trace_events(struct probe_trace_event *tevs,
812 int ntevs)
813 {
814 struct ref_reloc_sym *reloc_sym;
815 struct map *map;
816 char *tmp;
817 int i, skipped = 0;
818
819 /* Skip post process if the target is an offline kernel */
820 if (symbol_conf.ignore_vmlinux_buildid)
821 return post_process_offline_probe_trace_events(tevs, ntevs,
822 symbol_conf.vmlinux_name);
823
824 reloc_sym = kernel_get_ref_reloc_sym(&map);
825 if (!reloc_sym) {
826 pr_warning("Relocated base symbol is not found! "
827 "Check /proc/sys/kernel/kptr_restrict\n"
828 "and /proc/sys/kernel/perf_event_paranoid. "
829 "Or run as privileged perf user.\n\n");
830 return -EINVAL;
831 }
832
833 for (i = 0; i < ntevs; i++) {
834 if (!tevs[i].point.address)
835 continue;
836 if (tevs[i].point.retprobe && !kretprobe_offset_is_supported())
837 continue;
838 /*
839 * If we found a wrong one, mark it by NULL symbol.
840 * Since addresses in debuginfo is same as objdump, we need
841 * to convert it to addresses on memory.
842 */
843 if (kprobe_warn_out_range(tevs[i].point.symbol,
844 map__objdump_2mem(map, tevs[i].point.address))) {
845 tmp = NULL;
846 skipped++;
847 } else {
848 tmp = strdup(reloc_sym->name);
849 if (!tmp)
850 return -ENOMEM;
851 }
852 /* If we have no realname, use symbol for it */
853 if (!tevs[i].point.realname)
854 tevs[i].point.realname = tevs[i].point.symbol;
855 else
856 free(tevs[i].point.symbol);
857 tevs[i].point.symbol = tmp;
858 tevs[i].point.offset = tevs[i].point.address -
859 (map->reloc ? reloc_sym->unrelocated_addr :
860 reloc_sym->addr);
861 }
862 return skipped;
863 }
864
865 void __weak
arch__post_process_probe_trace_events(struct perf_probe_event * pev __maybe_unused,int ntevs __maybe_unused)866 arch__post_process_probe_trace_events(struct perf_probe_event *pev __maybe_unused,
867 int ntevs __maybe_unused)
868 {
869 }
870
871 /* Post processing the probe events */
post_process_probe_trace_events(struct perf_probe_event * pev,struct probe_trace_event * tevs,int ntevs,const char * module,bool uprobe,struct debuginfo * dinfo)872 static int post_process_probe_trace_events(struct perf_probe_event *pev,
873 struct probe_trace_event *tevs,
874 int ntevs, const char *module,
875 bool uprobe, struct debuginfo *dinfo)
876 {
877 int ret;
878
879 if (uprobe)
880 ret = add_exec_to_probe_trace_events(tevs, ntevs, module,
881 pev->nsi);
882 else if (module)
883 /* Currently ref_reloc_sym based probe is not for drivers */
884 ret = post_process_module_probe_trace_events(tevs, ntevs,
885 module, dinfo);
886 else
887 ret = post_process_kernel_probe_trace_events(tevs, ntevs);
888
889 if (ret >= 0)
890 arch__post_process_probe_trace_events(pev, ntevs);
891
892 return ret;
893 }
894
895 /* Try to find perf_probe_event with debuginfo */
try_to_find_probe_trace_events(struct perf_probe_event * pev,struct probe_trace_event ** tevs)896 static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
897 struct probe_trace_event **tevs)
898 {
899 bool need_dwarf = perf_probe_event_need_dwarf(pev);
900 struct perf_probe_point tmp;
901 struct debuginfo *dinfo;
902 int ntevs, ret = 0;
903
904 /* Workaround for gcc #98776 issue.
905 * Perf failed to add kretprobe event with debuginfo of vmlinux which is
906 * compiled by gcc with -fpatchable-function-entry option enabled. The
907 * same issue with kernel module. The retprobe doesn`t need debuginfo.
908 * This workaround solution use map to query the probe function address
909 * for retprobe event.
910 */
911 if (pev->point.retprobe)
912 return 0;
913
914 dinfo = open_debuginfo(pev->target, pev->nsi, !need_dwarf);
915 if (!dinfo) {
916 if (need_dwarf)
917 return -ENOENT;
918 pr_debug("Could not open debuginfo. Try to use symbols.\n");
919 return 0;
920 }
921
922 pr_debug("Try to find probe point from debuginfo.\n");
923 /* Searching trace events corresponding to a probe event */
924 ntevs = debuginfo__find_trace_events(dinfo, pev, tevs);
925
926 if (ntevs == 0) { /* Not found, retry with an alternative */
927 ret = get_alternative_probe_event(dinfo, pev, &tmp);
928 if (!ret) {
929 ntevs = debuginfo__find_trace_events(dinfo, pev, tevs);
930 /*
931 * Write back to the original probe_event for
932 * setting appropriate (user given) event name
933 */
934 clear_perf_probe_point(&pev->point);
935 memcpy(&pev->point, &tmp, sizeof(tmp));
936 }
937 }
938
939 if (ntevs > 0) { /* Succeeded to find trace events */
940 pr_debug("Found %d probe_trace_events.\n", ntevs);
941 ret = post_process_probe_trace_events(pev, *tevs, ntevs,
942 pev->target, pev->uprobes, dinfo);
943 if (ret < 0 || ret == ntevs) {
944 pr_debug("Post processing failed or all events are skipped. (%d)\n", ret);
945 clear_probe_trace_events(*tevs, ntevs);
946 zfree(tevs);
947 ntevs = 0;
948 }
949 }
950
951 debuginfo__delete(dinfo);
952
953 if (ntevs == 0) { /* No error but failed to find probe point. */
954 pr_warning("Probe point '%s' not found.\n",
955 synthesize_perf_probe_point(&pev->point));
956 return -ENOENT;
957 } else if (ntevs < 0) {
958 /* Error path : ntevs < 0 */
959 pr_debug("An error occurred in debuginfo analysis (%d).\n", ntevs);
960 if (ntevs == -EBADF)
961 pr_warning("Warning: No dwarf info found in the vmlinux - "
962 "please rebuild kernel with CONFIG_DEBUG_INFO=y.\n");
963 if (!need_dwarf) {
964 pr_debug("Trying to use symbols.\n");
965 return 0;
966 }
967 }
968 return ntevs;
969 }
970
971 #define LINEBUF_SIZE 256
972 #define NR_ADDITIONAL_LINES 2
973
__show_one_line(FILE * fp,int l,bool skip,bool show_num)974 static int __show_one_line(FILE *fp, int l, bool skip, bool show_num)
975 {
976 char buf[LINEBUF_SIZE], sbuf[STRERR_BUFSIZE];
977 const char *color = show_num ? "" : PERF_COLOR_BLUE;
978 const char *prefix = NULL;
979
980 do {
981 if (fgets(buf, LINEBUF_SIZE, fp) == NULL)
982 goto error;
983 if (skip)
984 continue;
985 if (!prefix) {
986 prefix = show_num ? "%7d " : " ";
987 color_fprintf(stdout, color, prefix, l);
988 }
989 color_fprintf(stdout, color, "%s", buf);
990
991 } while (strchr(buf, '\n') == NULL);
992
993 return 1;
994 error:
995 if (ferror(fp)) {
996 pr_warning("File read error: %s\n",
997 str_error_r(errno, sbuf, sizeof(sbuf)));
998 return -1;
999 }
1000 return 0;
1001 }
1002
_show_one_line(FILE * fp,int l,bool skip,bool show_num)1003 static int _show_one_line(FILE *fp, int l, bool skip, bool show_num)
1004 {
1005 int rv = __show_one_line(fp, l, skip, show_num);
1006 if (rv == 0) {
1007 pr_warning("Source file is shorter than expected.\n");
1008 rv = -1;
1009 }
1010 return rv;
1011 }
1012
1013 #define show_one_line_with_num(f,l) _show_one_line(f,l,false,true)
1014 #define show_one_line(f,l) _show_one_line(f,l,false,false)
1015 #define skip_one_line(f,l) _show_one_line(f,l,true,false)
1016 #define show_one_line_or_eof(f,l) __show_one_line(f,l,false,false)
1017
1018 /*
1019 * Show line-range always requires debuginfo to find source file and
1020 * line number.
1021 */
__show_line_range(struct line_range * lr,const char * module,bool user)1022 static int __show_line_range(struct line_range *lr, const char *module,
1023 bool user)
1024 {
1025 struct build_id bid;
1026 int l = 1;
1027 struct int_node *ln;
1028 struct debuginfo *dinfo;
1029 FILE *fp;
1030 int ret;
1031 char *tmp;
1032 char sbuf[STRERR_BUFSIZE];
1033 char sbuild_id[SBUILD_ID_SIZE] = "";
1034
1035 /* Search a line range */
1036 dinfo = open_debuginfo(module, NULL, false);
1037 if (!dinfo)
1038 return -ENOENT;
1039
1040 ret = debuginfo__find_line_range(dinfo, lr);
1041 if (!ret) { /* Not found, retry with an alternative */
1042 ret = get_alternative_line_range(dinfo, lr, module, user);
1043 if (!ret)
1044 ret = debuginfo__find_line_range(dinfo, lr);
1045 }
1046 if (dinfo->build_id) {
1047 build_id__init(&bid, dinfo->build_id, BUILD_ID_SIZE);
1048 build_id__sprintf(&bid, sbuild_id);
1049 }
1050 debuginfo__delete(dinfo);
1051 if (ret == 0 || ret == -ENOENT) {
1052 pr_warning("Specified source line is not found.\n");
1053 return -ENOENT;
1054 } else if (ret < 0) {
1055 pr_warning("Debuginfo analysis failed.\n");
1056 return ret;
1057 }
1058
1059 /* Convert source file path */
1060 tmp = lr->path;
1061 ret = find_source_path(tmp, sbuild_id, lr->comp_dir, &lr->path);
1062
1063 /* Free old path when new path is assigned */
1064 if (tmp != lr->path)
1065 free(tmp);
1066
1067 if (ret < 0) {
1068 pr_warning("Failed to find source file path.\n");
1069 return ret;
1070 }
1071
1072 setup_pager();
1073
1074 if (lr->function)
1075 fprintf(stdout, "<%s@%s:%d>\n", lr->function, lr->path,
1076 lr->start - lr->offset);
1077 else
1078 fprintf(stdout, "<%s:%d>\n", lr->path, lr->start);
1079
1080 fp = fopen(lr->path, "r");
1081 if (fp == NULL) {
1082 pr_warning("Failed to open %s: %s\n", lr->path,
1083 str_error_r(errno, sbuf, sizeof(sbuf)));
1084 return -errno;
1085 }
1086 /* Skip to starting line number */
1087 while (l < lr->start) {
1088 ret = skip_one_line(fp, l++);
1089 if (ret < 0)
1090 goto end;
1091 }
1092
1093 intlist__for_each_entry(ln, lr->line_list) {
1094 for (; ln->i > (unsigned long)l; l++) {
1095 ret = show_one_line(fp, l - lr->offset);
1096 if (ret < 0)
1097 goto end;
1098 }
1099 ret = show_one_line_with_num(fp, l++ - lr->offset);
1100 if (ret < 0)
1101 goto end;
1102 }
1103
1104 if (lr->end == INT_MAX)
1105 lr->end = l + NR_ADDITIONAL_LINES;
1106 while (l <= lr->end) {
1107 ret = show_one_line_or_eof(fp, l++ - lr->offset);
1108 if (ret <= 0)
1109 break;
1110 }
1111 end:
1112 fclose(fp);
1113 return ret;
1114 }
1115
show_line_range(struct line_range * lr,const char * module,struct nsinfo * nsi,bool user)1116 int show_line_range(struct line_range *lr, const char *module,
1117 struct nsinfo *nsi, bool user)
1118 {
1119 int ret;
1120 struct nscookie nsc;
1121
1122 ret = init_probe_symbol_maps(user);
1123 if (ret < 0)
1124 return ret;
1125 nsinfo__mountns_enter(nsi, &nsc);
1126 ret = __show_line_range(lr, module, user);
1127 nsinfo__mountns_exit(&nsc);
1128 exit_probe_symbol_maps();
1129
1130 return ret;
1131 }
1132
show_available_vars_at(struct debuginfo * dinfo,struct perf_probe_event * pev,struct strfilter * _filter)1133 static int show_available_vars_at(struct debuginfo *dinfo,
1134 struct perf_probe_event *pev,
1135 struct strfilter *_filter)
1136 {
1137 char *buf;
1138 int ret, i, nvars;
1139 struct str_node *node;
1140 struct variable_list *vls = NULL, *vl;
1141 struct perf_probe_point tmp;
1142 const char *var;
1143
1144 buf = synthesize_perf_probe_point(&pev->point);
1145 if (!buf)
1146 return -EINVAL;
1147 pr_debug("Searching variables at %s\n", buf);
1148
1149 ret = debuginfo__find_available_vars_at(dinfo, pev, &vls);
1150 if (!ret) { /* Not found, retry with an alternative */
1151 ret = get_alternative_probe_event(dinfo, pev, &tmp);
1152 if (!ret) {
1153 ret = debuginfo__find_available_vars_at(dinfo, pev,
1154 &vls);
1155 /* Release the old probe_point */
1156 clear_perf_probe_point(&tmp);
1157 }
1158 }
1159 if (ret <= 0) {
1160 if (ret == 0 || ret == -ENOENT) {
1161 pr_err("Failed to find the address of %s\n", buf);
1162 ret = -ENOENT;
1163 } else
1164 pr_warning("Debuginfo analysis failed.\n");
1165 goto end;
1166 }
1167
1168 /* Some variables are found */
1169 fprintf(stdout, "Available variables at %s\n", buf);
1170 for (i = 0; i < ret; i++) {
1171 vl = &vls[i];
1172 /*
1173 * A probe point might be converted to
1174 * several trace points.
1175 */
1176 fprintf(stdout, "\t@<%s+%lu>\n", vl->point.symbol,
1177 vl->point.offset);
1178 zfree(&vl->point.symbol);
1179 nvars = 0;
1180 if (vl->vars) {
1181 strlist__for_each_entry(node, vl->vars) {
1182 var = strchr(node->s, '\t') + 1;
1183 if (strfilter__compare(_filter, var)) {
1184 fprintf(stdout, "\t\t%s\n", node->s);
1185 nvars++;
1186 }
1187 }
1188 strlist__delete(vl->vars);
1189 }
1190 if (nvars == 0)
1191 fprintf(stdout, "\t\t(No matched variables)\n");
1192 }
1193 free(vls);
1194 end:
1195 free(buf);
1196 return ret;
1197 }
1198
1199 /* Show available variables on given probe point */
show_available_vars(struct perf_probe_event * pevs,int npevs,struct strfilter * _filter)1200 int show_available_vars(struct perf_probe_event *pevs, int npevs,
1201 struct strfilter *_filter)
1202 {
1203 int i, ret = 0;
1204 struct debuginfo *dinfo;
1205
1206 ret = init_probe_symbol_maps(pevs->uprobes);
1207 if (ret < 0)
1208 return ret;
1209
1210 dinfo = open_debuginfo(pevs->target, pevs->nsi, false);
1211 if (!dinfo) {
1212 ret = -ENOENT;
1213 goto out;
1214 }
1215
1216 setup_pager();
1217
1218 for (i = 0; i < npevs && ret >= 0; i++)
1219 ret = show_available_vars_at(dinfo, &pevs[i], _filter);
1220
1221 debuginfo__delete(dinfo);
1222 out:
1223 exit_probe_symbol_maps();
1224 return ret;
1225 }
1226
1227 #else /* !HAVE_DWARF_SUPPORT */
1228
debuginfo_cache__exit(void)1229 static void debuginfo_cache__exit(void)
1230 {
1231 }
1232
1233 static int
find_perf_probe_point_from_dwarf(struct probe_trace_point * tp __maybe_unused,struct perf_probe_point * pp __maybe_unused,bool is_kprobe __maybe_unused)1234 find_perf_probe_point_from_dwarf(struct probe_trace_point *tp __maybe_unused,
1235 struct perf_probe_point *pp __maybe_unused,
1236 bool is_kprobe __maybe_unused)
1237 {
1238 return -ENOSYS;
1239 }
1240
try_to_find_probe_trace_events(struct perf_probe_event * pev,struct probe_trace_event ** tevs __maybe_unused)1241 static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
1242 struct probe_trace_event **tevs __maybe_unused)
1243 {
1244 if (perf_probe_event_need_dwarf(pev)) {
1245 pr_warning("Debuginfo-analysis is not supported.\n");
1246 return -ENOSYS;
1247 }
1248
1249 return 0;
1250 }
1251
show_line_range(struct line_range * lr __maybe_unused,const char * module __maybe_unused,struct nsinfo * nsi __maybe_unused,bool user __maybe_unused)1252 int show_line_range(struct line_range *lr __maybe_unused,
1253 const char *module __maybe_unused,
1254 struct nsinfo *nsi __maybe_unused,
1255 bool user __maybe_unused)
1256 {
1257 pr_warning("Debuginfo-analysis is not supported.\n");
1258 return -ENOSYS;
1259 }
1260
show_available_vars(struct perf_probe_event * pevs __maybe_unused,int npevs __maybe_unused,struct strfilter * filter __maybe_unused)1261 int show_available_vars(struct perf_probe_event *pevs __maybe_unused,
1262 int npevs __maybe_unused,
1263 struct strfilter *filter __maybe_unused)
1264 {
1265 pr_warning("Debuginfo-analysis is not supported.\n");
1266 return -ENOSYS;
1267 }
1268 #endif
1269
line_range__clear(struct line_range * lr)1270 void line_range__clear(struct line_range *lr)
1271 {
1272 zfree(&lr->function);
1273 zfree(&lr->file);
1274 zfree(&lr->path);
1275 zfree(&lr->comp_dir);
1276 intlist__delete(lr->line_list);
1277 }
1278
line_range__init(struct line_range * lr)1279 int line_range__init(struct line_range *lr)
1280 {
1281 memset(lr, 0, sizeof(*lr));
1282 lr->line_list = intlist__new(NULL);
1283 if (!lr->line_list)
1284 return -ENOMEM;
1285 else
1286 return 0;
1287 }
1288
parse_line_num(char ** ptr,int * val,const char * what)1289 static int parse_line_num(char **ptr, int *val, const char *what)
1290 {
1291 const char *start = *ptr;
1292
1293 errno = 0;
1294 *val = strtol(*ptr, ptr, 0);
1295 if (errno || *ptr == start) {
1296 semantic_error("'%s' is not a valid number.\n", what);
1297 return -EINVAL;
1298 }
1299 return 0;
1300 }
1301
1302 /* Check the name is good for event, group or function */
is_c_func_name(const char * name)1303 static bool is_c_func_name(const char *name)
1304 {
1305 if (!isalpha(*name) && *name != '_')
1306 return false;
1307 while (*++name != '\0') {
1308 if (!isalpha(*name) && !isdigit(*name) && *name != '_')
1309 return false;
1310 }
1311 return true;
1312 }
1313
1314 /*
1315 * Stuff 'lr' according to the line range described by 'arg'.
1316 * The line range syntax is described by:
1317 *
1318 * SRC[:SLN[+NUM|-ELN]]
1319 * FNC[@SRC][:SLN[+NUM|-ELN]]
1320 */
parse_line_range_desc(const char * arg,struct line_range * lr)1321 int parse_line_range_desc(const char *arg, struct line_range *lr)
1322 {
1323 char *range, *file, *name = strdup(arg);
1324 int err;
1325
1326 if (!name)
1327 return -ENOMEM;
1328
1329 lr->start = 0;
1330 lr->end = INT_MAX;
1331
1332 range = strchr(name, ':');
1333 if (range) {
1334 *range++ = '\0';
1335
1336 err = parse_line_num(&range, &lr->start, "start line");
1337 if (err)
1338 goto err;
1339
1340 if (*range == '+' || *range == '-') {
1341 const char c = *range++;
1342
1343 err = parse_line_num(&range, &lr->end, "end line");
1344 if (err)
1345 goto err;
1346
1347 if (c == '+') {
1348 lr->end += lr->start;
1349 /*
1350 * Adjust the number of lines here.
1351 * If the number of lines == 1, the
1352 * the end of line should be equal to
1353 * the start of line.
1354 */
1355 lr->end--;
1356 }
1357 }
1358
1359 pr_debug("Line range is %d to %d\n", lr->start, lr->end);
1360
1361 err = -EINVAL;
1362 if (lr->start > lr->end) {
1363 semantic_error("Start line must be smaller"
1364 " than end line.\n");
1365 goto err;
1366 }
1367 if (*range != '\0') {
1368 semantic_error("Tailing with invalid str '%s'.\n", range);
1369 goto err;
1370 }
1371 }
1372
1373 file = strchr(name, '@');
1374 if (file) {
1375 *file = '\0';
1376 lr->file = strdup(++file);
1377 if (lr->file == NULL) {
1378 err = -ENOMEM;
1379 goto err;
1380 }
1381 lr->function = name;
1382 } else if (strchr(name, '/') || strchr(name, '.'))
1383 lr->file = name;
1384 else if (is_c_func_name(name))/* We reuse it for checking funcname */
1385 lr->function = name;
1386 else { /* Invalid name */
1387 semantic_error("'%s' is not a valid function name.\n", name);
1388 err = -EINVAL;
1389 goto err;
1390 }
1391
1392 return 0;
1393 err:
1394 free(name);
1395 return err;
1396 }
1397
parse_perf_probe_event_name(char ** arg,struct perf_probe_event * pev)1398 static int parse_perf_probe_event_name(char **arg, struct perf_probe_event *pev)
1399 {
1400 char *ptr;
1401
1402 ptr = strpbrk_esc(*arg, ":");
1403 if (ptr) {
1404 *ptr = '\0';
1405 if (!pev->sdt && !is_c_func_name(*arg))
1406 goto ng_name;
1407 pev->group = strdup_esc(*arg);
1408 if (!pev->group)
1409 return -ENOMEM;
1410 *arg = ptr + 1;
1411 } else
1412 pev->group = NULL;
1413
1414 pev->event = strdup_esc(*arg);
1415 if (pev->event == NULL)
1416 return -ENOMEM;
1417
1418 if (!pev->sdt && !is_c_func_name(pev->event)) {
1419 zfree(&pev->event);
1420 ng_name:
1421 zfree(&pev->group);
1422 semantic_error("%s is bad for event name -it must "
1423 "follow C symbol-naming rule.\n", *arg);
1424 return -EINVAL;
1425 }
1426 return 0;
1427 }
1428
1429 /* Parse probepoint definition. */
parse_perf_probe_point(char * arg,struct perf_probe_event * pev)1430 static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev)
1431 {
1432 struct perf_probe_point *pp = &pev->point;
1433 char *ptr, *tmp;
1434 char c, nc = 0;
1435 bool file_spec = false;
1436 int ret;
1437
1438 /*
1439 * <Syntax>
1440 * perf probe [GRP:][EVENT=]SRC[:LN|;PTN]
1441 * perf probe [GRP:][EVENT=]FUNC[@SRC][+OFFS|%return|:LN|;PAT]
1442 * perf probe %[GRP:]SDT_EVENT
1443 */
1444 if (!arg)
1445 return -EINVAL;
1446
1447 if (is_sdt_event(arg)) {
1448 pev->sdt = true;
1449 if (arg[0] == '%')
1450 arg++;
1451 }
1452
1453 ptr = strpbrk_esc(arg, ";=@+%");
1454 if (pev->sdt) {
1455 if (ptr) {
1456 if (*ptr != '@') {
1457 semantic_error("%s must be an SDT name.\n",
1458 arg);
1459 return -EINVAL;
1460 }
1461 /* This must be a target file name or build id */
1462 tmp = build_id_cache__complement(ptr + 1);
1463 if (tmp) {
1464 pev->target = build_id_cache__origname(tmp);
1465 free(tmp);
1466 } else
1467 pev->target = strdup_esc(ptr + 1);
1468 if (!pev->target)
1469 return -ENOMEM;
1470 *ptr = '\0';
1471 }
1472 ret = parse_perf_probe_event_name(&arg, pev);
1473 if (ret == 0) {
1474 if (asprintf(&pev->point.function, "%%%s", pev->event) < 0)
1475 ret = -errno;
1476 }
1477 return ret;
1478 }
1479
1480 if (ptr && *ptr == '=') { /* Event name */
1481 *ptr = '\0';
1482 tmp = ptr + 1;
1483 ret = parse_perf_probe_event_name(&arg, pev);
1484 if (ret < 0)
1485 return ret;
1486
1487 arg = tmp;
1488 }
1489
1490 /*
1491 * Check arg is function or file name and copy it.
1492 *
1493 * We consider arg to be a file spec if and only if it satisfies
1494 * all of the below criteria::
1495 * - it does not include any of "+@%",
1496 * - it includes one of ":;", and
1497 * - it has a period '.' in the name.
1498 *
1499 * Otherwise, we consider arg to be a function specification.
1500 */
1501 if (!strpbrk_esc(arg, "+@%")) {
1502 ptr = strpbrk_esc(arg, ";:");
1503 /* This is a file spec if it includes a '.' before ; or : */
1504 if (ptr && memchr(arg, '.', ptr - arg))
1505 file_spec = true;
1506 }
1507
1508 ptr = strpbrk_esc(arg, ";:+@%");
1509 if (ptr) {
1510 nc = *ptr;
1511 *ptr++ = '\0';
1512 }
1513
1514 if (arg[0] == '\0')
1515 tmp = NULL;
1516 else {
1517 tmp = strdup_esc(arg);
1518 if (tmp == NULL)
1519 return -ENOMEM;
1520 }
1521
1522 if (file_spec)
1523 pp->file = tmp;
1524 else {
1525 pp->function = tmp;
1526
1527 /*
1528 * Keep pp->function even if this is absolute address,
1529 * so it can mark whether abs_address is valid.
1530 * Which make 'perf probe lib.bin 0x0' possible.
1531 *
1532 * Note that checking length of tmp is not needed
1533 * because when we access tmp[1] we know tmp[0] is '0',
1534 * so tmp[1] should always valid (but could be '\0').
1535 */
1536 if (tmp && !strncmp(tmp, "0x", 2)) {
1537 pp->abs_address = strtoull(pp->function, &tmp, 0);
1538 if (*tmp != '\0') {
1539 semantic_error("Invalid absolute address.\n");
1540 return -EINVAL;
1541 }
1542 }
1543 }
1544
1545 /* Parse other options */
1546 while (ptr) {
1547 arg = ptr;
1548 c = nc;
1549 if (c == ';') { /* Lazy pattern must be the last part */
1550 pp->lazy_line = strdup(arg); /* let leave escapes */
1551 if (pp->lazy_line == NULL)
1552 return -ENOMEM;
1553 break;
1554 }
1555 ptr = strpbrk_esc(arg, ";:+@%");
1556 if (ptr) {
1557 nc = *ptr;
1558 *ptr++ = '\0';
1559 }
1560 switch (c) {
1561 case ':': /* Line number */
1562 pp->line = strtoul(arg, &tmp, 0);
1563 if (*tmp != '\0') {
1564 semantic_error("There is non-digit char"
1565 " in line number.\n");
1566 return -EINVAL;
1567 }
1568 break;
1569 case '+': /* Byte offset from a symbol */
1570 pp->offset = strtoul(arg, &tmp, 0);
1571 if (*tmp != '\0') {
1572 semantic_error("There is non-digit character"
1573 " in offset.\n");
1574 return -EINVAL;
1575 }
1576 break;
1577 case '@': /* File name */
1578 if (pp->file) {
1579 semantic_error("SRC@SRC is not allowed.\n");
1580 return -EINVAL;
1581 }
1582 pp->file = strdup_esc(arg);
1583 if (pp->file == NULL)
1584 return -ENOMEM;
1585 break;
1586 case '%': /* Probe places */
1587 if (strcmp(arg, "return") == 0) {
1588 pp->retprobe = 1;
1589 } else { /* Others not supported yet */
1590 semantic_error("%%%s is not supported.\n", arg);
1591 return -ENOTSUP;
1592 }
1593 break;
1594 default: /* Buggy case */
1595 pr_err("This program has a bug at %s:%d.\n",
1596 __FILE__, __LINE__);
1597 return -ENOTSUP;
1598 break;
1599 }
1600 }
1601
1602 /* Exclusion check */
1603 if (pp->lazy_line && pp->line) {
1604 semantic_error("Lazy pattern can't be used with"
1605 " line number.\n");
1606 return -EINVAL;
1607 }
1608
1609 if (pp->lazy_line && pp->offset) {
1610 semantic_error("Lazy pattern can't be used with offset.\n");
1611 return -EINVAL;
1612 }
1613
1614 if (pp->line && pp->offset) {
1615 semantic_error("Offset can't be used with line number.\n");
1616 return -EINVAL;
1617 }
1618
1619 if (!pp->line && !pp->lazy_line && pp->file && !pp->function) {
1620 semantic_error("File always requires line number or "
1621 "lazy pattern.\n");
1622 return -EINVAL;
1623 }
1624
1625 if (pp->offset && !pp->function) {
1626 semantic_error("Offset requires an entry function.\n");
1627 return -EINVAL;
1628 }
1629
1630 if ((pp->offset || pp->line || pp->lazy_line) && pp->retprobe) {
1631 semantic_error("Offset/Line/Lazy pattern can't be used with "
1632 "return probe.\n");
1633 return -EINVAL;
1634 }
1635
1636 pr_debug("symbol:%s file:%s line:%d offset:%lu return:%d lazy:%s\n",
1637 pp->function, pp->file, pp->line, pp->offset, pp->retprobe,
1638 pp->lazy_line);
1639 return 0;
1640 }
1641
1642 /* Parse perf-probe event argument */
parse_perf_probe_arg(char * str,struct perf_probe_arg * arg)1643 static int parse_perf_probe_arg(char *str, struct perf_probe_arg *arg)
1644 {
1645 char *tmp, *goodname;
1646 struct perf_probe_arg_field **fieldp;
1647
1648 pr_debug("parsing arg: %s into ", str);
1649
1650 tmp = strchr(str, '=');
1651 if (tmp) {
1652 arg->name = strndup(str, tmp - str);
1653 if (arg->name == NULL)
1654 return -ENOMEM;
1655 pr_debug("name:%s ", arg->name);
1656 str = tmp + 1;
1657 }
1658
1659 tmp = strchr(str, '@');
1660 if (tmp && tmp != str && !strcmp(tmp + 1, "user")) { /* user attr */
1661 if (!user_access_is_supported()) {
1662 semantic_error("ftrace does not support user access\n");
1663 return -EINVAL;
1664 }
1665 *tmp = '\0';
1666 arg->user_access = true;
1667 pr_debug("user_access ");
1668 }
1669
1670 tmp = strchr(str, ':');
1671 if (tmp) { /* Type setting */
1672 *tmp = '\0';
1673 arg->type = strdup(tmp + 1);
1674 if (arg->type == NULL)
1675 return -ENOMEM;
1676 pr_debug("type:%s ", arg->type);
1677 }
1678
1679 tmp = strpbrk(str, "-.[");
1680 if (!is_c_varname(str) || !tmp) {
1681 /* A variable, register, symbol or special value */
1682 arg->var = strdup(str);
1683 if (arg->var == NULL)
1684 return -ENOMEM;
1685 pr_debug("%s\n", arg->var);
1686 return 0;
1687 }
1688
1689 /* Structure fields or array element */
1690 arg->var = strndup(str, tmp - str);
1691 if (arg->var == NULL)
1692 return -ENOMEM;
1693 goodname = arg->var;
1694 pr_debug("%s, ", arg->var);
1695 fieldp = &arg->field;
1696
1697 do {
1698 *fieldp = zalloc(sizeof(struct perf_probe_arg_field));
1699 if (*fieldp == NULL)
1700 return -ENOMEM;
1701 if (*tmp == '[') { /* Array */
1702 str = tmp;
1703 (*fieldp)->index = strtol(str + 1, &tmp, 0);
1704 (*fieldp)->ref = true;
1705 if (*tmp != ']' || tmp == str + 1) {
1706 semantic_error("Array index must be a"
1707 " number.\n");
1708 return -EINVAL;
1709 }
1710 tmp++;
1711 if (*tmp == '\0')
1712 tmp = NULL;
1713 } else { /* Structure */
1714 if (*tmp == '.') {
1715 str = tmp + 1;
1716 (*fieldp)->ref = false;
1717 } else if (tmp[1] == '>') {
1718 str = tmp + 2;
1719 (*fieldp)->ref = true;
1720 } else {
1721 semantic_error("Argument parse error: %s\n",
1722 str);
1723 return -EINVAL;
1724 }
1725 tmp = strpbrk(str, "-.[");
1726 }
1727 if (tmp) {
1728 (*fieldp)->name = strndup(str, tmp - str);
1729 if ((*fieldp)->name == NULL)
1730 return -ENOMEM;
1731 if (*str != '[')
1732 goodname = (*fieldp)->name;
1733 pr_debug("%s(%d), ", (*fieldp)->name, (*fieldp)->ref);
1734 fieldp = &(*fieldp)->next;
1735 }
1736 } while (tmp);
1737 (*fieldp)->name = strdup(str);
1738 if ((*fieldp)->name == NULL)
1739 return -ENOMEM;
1740 if (*str != '[')
1741 goodname = (*fieldp)->name;
1742 pr_debug("%s(%d)\n", (*fieldp)->name, (*fieldp)->ref);
1743
1744 /* If no name is specified, set the last field name (not array index)*/
1745 if (!arg->name) {
1746 arg->name = strdup(goodname);
1747 if (arg->name == NULL)
1748 return -ENOMEM;
1749 }
1750 return 0;
1751 }
1752
1753 /* Parse perf-probe event command */
parse_perf_probe_command(const char * cmd,struct perf_probe_event * pev)1754 int parse_perf_probe_command(const char *cmd, struct perf_probe_event *pev)
1755 {
1756 char **argv;
1757 int argc, i, ret = 0;
1758
1759 argv = argv_split(cmd, &argc);
1760 if (!argv) {
1761 pr_debug("Failed to split arguments.\n");
1762 return -ENOMEM;
1763 }
1764 if (argc - 1 > MAX_PROBE_ARGS) {
1765 semantic_error("Too many probe arguments (%d).\n", argc - 1);
1766 ret = -ERANGE;
1767 goto out;
1768 }
1769 /* Parse probe point */
1770 ret = parse_perf_probe_point(argv[0], pev);
1771 if (ret < 0)
1772 goto out;
1773
1774 /* Generate event name if needed */
1775 if (!pev->event && pev->point.function && pev->point.line
1776 && !pev->point.lazy_line && !pev->point.offset) {
1777 if (asprintf(&pev->event, "%s_L%d", pev->point.function,
1778 pev->point.line) < 0) {
1779 ret = -ENOMEM;
1780 goto out;
1781 }
1782 }
1783
1784 /* Copy arguments and ensure return probe has no C argument */
1785 pev->nargs = argc - 1;
1786 pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs);
1787 if (pev->args == NULL) {
1788 ret = -ENOMEM;
1789 goto out;
1790 }
1791 for (i = 0; i < pev->nargs && ret >= 0; i++) {
1792 ret = parse_perf_probe_arg(argv[i + 1], &pev->args[i]);
1793 if (ret >= 0 &&
1794 is_c_varname(pev->args[i].var) && pev->point.retprobe) {
1795 semantic_error("You can't specify local variable for"
1796 " kretprobe.\n");
1797 ret = -EINVAL;
1798 }
1799 }
1800 out:
1801 argv_free(argv);
1802
1803 return ret;
1804 }
1805
1806 /* Returns true if *any* ARG is either C variable, $params or $vars. */
perf_probe_with_var(struct perf_probe_event * pev)1807 bool perf_probe_with_var(struct perf_probe_event *pev)
1808 {
1809 int i = 0;
1810
1811 for (i = 0; i < pev->nargs; i++)
1812 if (is_c_varname(pev->args[i].var) ||
1813 !strcmp(pev->args[i].var, PROBE_ARG_PARAMS) ||
1814 !strcmp(pev->args[i].var, PROBE_ARG_VARS))
1815 return true;
1816 return false;
1817 }
1818
1819 /* Return true if this perf_probe_event requires debuginfo */
perf_probe_event_need_dwarf(struct perf_probe_event * pev)1820 bool perf_probe_event_need_dwarf(struct perf_probe_event *pev)
1821 {
1822 if (pev->point.file || pev->point.line || pev->point.lazy_line)
1823 return true;
1824
1825 if (perf_probe_with_var(pev))
1826 return true;
1827
1828 return false;
1829 }
1830
1831 /* Parse probe_events event into struct probe_point */
parse_probe_trace_command(const char * cmd,struct probe_trace_event * tev)1832 int parse_probe_trace_command(const char *cmd, struct probe_trace_event *tev)
1833 {
1834 struct probe_trace_point *tp = &tev->point;
1835 char pr;
1836 char *p;
1837 char *argv0_str = NULL, *fmt, *fmt1_str, *fmt2_str, *fmt3_str;
1838 int ret, i, argc;
1839 char **argv;
1840
1841 pr_debug("Parsing probe_events: %s\n", cmd);
1842 argv = argv_split(cmd, &argc);
1843 if (!argv) {
1844 pr_debug("Failed to split arguments.\n");
1845 return -ENOMEM;
1846 }
1847 if (argc < 2) {
1848 semantic_error("Too few probe arguments.\n");
1849 ret = -ERANGE;
1850 goto out;
1851 }
1852
1853 /* Scan event and group name. */
1854 argv0_str = strdup(argv[0]);
1855 if (argv0_str == NULL) {
1856 ret = -ENOMEM;
1857 goto out;
1858 }
1859 fmt1_str = strtok_r(argv0_str, ":", &fmt);
1860 fmt2_str = strtok_r(NULL, "/", &fmt);
1861 fmt3_str = strtok_r(NULL, " \t", &fmt);
1862 if (fmt1_str == NULL || fmt2_str == NULL || fmt3_str == NULL) {
1863 semantic_error("Failed to parse event name: %s\n", argv[0]);
1864 ret = -EINVAL;
1865 goto out;
1866 }
1867 pr = fmt1_str[0];
1868 tev->group = strdup(fmt2_str);
1869 tev->event = strdup(fmt3_str);
1870 if (tev->group == NULL || tev->event == NULL) {
1871 ret = -ENOMEM;
1872 goto out;
1873 }
1874 pr_debug("Group:%s Event:%s probe:%c\n", tev->group, tev->event, pr);
1875
1876 tp->retprobe = (pr == 'r');
1877
1878 /* Scan module name(if there), function name and offset */
1879 p = strchr(argv[1], ':');
1880 if (p) {
1881 tp->module = strndup(argv[1], p - argv[1]);
1882 if (!tp->module) {
1883 ret = -ENOMEM;
1884 goto out;
1885 }
1886 tev->uprobes = (tp->module[0] == '/');
1887 p++;
1888 } else
1889 p = argv[1];
1890 fmt1_str = strtok_r(p, "+", &fmt);
1891 /* only the address started with 0x */
1892 if (fmt1_str[0] == '0') {
1893 /*
1894 * Fix a special case:
1895 * if address == 0, kernel reports something like:
1896 * p:probe_libc/abs_0 /lib/libc-2.18.so:0x (null) arg1=%ax
1897 * Newer kernel may fix that, but we want to
1898 * support old kernel also.
1899 */
1900 if (strcmp(fmt1_str, "0x") == 0) {
1901 if (!argv[2] || strcmp(argv[2], "(null)")) {
1902 ret = -EINVAL;
1903 goto out;
1904 }
1905 tp->address = 0;
1906
1907 free(argv[2]);
1908 for (i = 2; argv[i + 1] != NULL; i++)
1909 argv[i] = argv[i + 1];
1910
1911 argv[i] = NULL;
1912 argc -= 1;
1913 } else
1914 tp->address = strtoull(fmt1_str, NULL, 0);
1915 } else {
1916 /* Only the symbol-based probe has offset */
1917 tp->symbol = strdup(fmt1_str);
1918 if (tp->symbol == NULL) {
1919 ret = -ENOMEM;
1920 goto out;
1921 }
1922 fmt2_str = strtok_r(NULL, "", &fmt);
1923 if (fmt2_str == NULL)
1924 tp->offset = 0;
1925 else
1926 tp->offset = strtoul(fmt2_str, NULL, 10);
1927 }
1928
1929 if (tev->uprobes) {
1930 fmt2_str = strchr(p, '(');
1931 if (fmt2_str)
1932 tp->ref_ctr_offset = strtoul(fmt2_str + 1, NULL, 0);
1933 }
1934
1935 tev->nargs = argc - 2;
1936 tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
1937 if (tev->args == NULL) {
1938 ret = -ENOMEM;
1939 goto out;
1940 }
1941 for (i = 0; i < tev->nargs; i++) {
1942 p = strchr(argv[i + 2], '=');
1943 if (p) /* We don't need which register is assigned. */
1944 *p++ = '\0';
1945 else
1946 p = argv[i + 2];
1947 tev->args[i].name = strdup(argv[i + 2]);
1948 /* TODO: parse regs and offset */
1949 tev->args[i].value = strdup(p);
1950 if (tev->args[i].name == NULL || tev->args[i].value == NULL) {
1951 ret = -ENOMEM;
1952 goto out;
1953 }
1954 }
1955 ret = 0;
1956 out:
1957 free(argv0_str);
1958 argv_free(argv);
1959 return ret;
1960 }
1961
1962 /* Compose only probe arg */
synthesize_perf_probe_arg(struct perf_probe_arg * pa)1963 char *synthesize_perf_probe_arg(struct perf_probe_arg *pa)
1964 {
1965 struct perf_probe_arg_field *field = pa->field;
1966 struct strbuf buf;
1967 char *ret = NULL;
1968 int err;
1969
1970 if (strbuf_init(&buf, 64) < 0)
1971 return NULL;
1972
1973 if (pa->name && pa->var)
1974 err = strbuf_addf(&buf, "%s=%s", pa->name, pa->var);
1975 else
1976 err = strbuf_addstr(&buf, pa->name ?: pa->var);
1977 if (err)
1978 goto out;
1979
1980 while (field) {
1981 if (field->name[0] == '[')
1982 err = strbuf_addstr(&buf, field->name);
1983 else
1984 err = strbuf_addf(&buf, "%s%s", field->ref ? "->" : ".",
1985 field->name);
1986 field = field->next;
1987 if (err)
1988 goto out;
1989 }
1990
1991 if (pa->type)
1992 if (strbuf_addf(&buf, ":%s", pa->type) < 0)
1993 goto out;
1994
1995 ret = strbuf_detach(&buf, NULL);
1996 out:
1997 strbuf_release(&buf);
1998 return ret;
1999 }
2000
2001 /* Compose only probe point (not argument) */
synthesize_perf_probe_point(struct perf_probe_point * pp)2002 char *synthesize_perf_probe_point(struct perf_probe_point *pp)
2003 {
2004 struct strbuf buf;
2005 char *tmp, *ret = NULL;
2006 int len, err = 0;
2007
2008 if (strbuf_init(&buf, 64) < 0)
2009 return NULL;
2010
2011 if (pp->function) {
2012 if (strbuf_addstr(&buf, pp->function) < 0)
2013 goto out;
2014 if (pp->offset)
2015 err = strbuf_addf(&buf, "+%lu", pp->offset);
2016 else if (pp->line)
2017 err = strbuf_addf(&buf, ":%d", pp->line);
2018 else if (pp->retprobe)
2019 err = strbuf_addstr(&buf, "%return");
2020 if (err)
2021 goto out;
2022 }
2023 if (pp->file) {
2024 tmp = pp->file;
2025 len = strlen(tmp);
2026 if (len > 30) {
2027 tmp = strchr(pp->file + len - 30, '/');
2028 tmp = tmp ? tmp + 1 : pp->file + len - 30;
2029 }
2030 err = strbuf_addf(&buf, "@%s", tmp);
2031 if (!err && !pp->function && pp->line)
2032 err = strbuf_addf(&buf, ":%d", pp->line);
2033 }
2034 if (!err)
2035 ret = strbuf_detach(&buf, NULL);
2036 out:
2037 strbuf_release(&buf);
2038 return ret;
2039 }
2040
synthesize_perf_probe_command(struct perf_probe_event * pev)2041 char *synthesize_perf_probe_command(struct perf_probe_event *pev)
2042 {
2043 struct strbuf buf;
2044 char *tmp, *ret = NULL;
2045 int i;
2046
2047 if (strbuf_init(&buf, 64))
2048 return NULL;
2049 if (pev->event)
2050 if (strbuf_addf(&buf, "%s:%s=", pev->group ?: PERFPROBE_GROUP,
2051 pev->event) < 0)
2052 goto out;
2053
2054 tmp = synthesize_perf_probe_point(&pev->point);
2055 if (!tmp || strbuf_addstr(&buf, tmp) < 0)
2056 goto out;
2057 free(tmp);
2058
2059 for (i = 0; i < pev->nargs; i++) {
2060 tmp = synthesize_perf_probe_arg(pev->args + i);
2061 if (!tmp || strbuf_addf(&buf, " %s", tmp) < 0)
2062 goto out;
2063 free(tmp);
2064 }
2065
2066 ret = strbuf_detach(&buf, NULL);
2067 out:
2068 strbuf_release(&buf);
2069 return ret;
2070 }
2071
__synthesize_probe_trace_arg_ref(struct probe_trace_arg_ref * ref,struct strbuf * buf,int depth)2072 static int __synthesize_probe_trace_arg_ref(struct probe_trace_arg_ref *ref,
2073 struct strbuf *buf, int depth)
2074 {
2075 int err;
2076 if (ref->next) {
2077 depth = __synthesize_probe_trace_arg_ref(ref->next, buf,
2078 depth + 1);
2079 if (depth < 0)
2080 return depth;
2081 }
2082 if (ref->user_access)
2083 err = strbuf_addf(buf, "%s%ld(", "+u", ref->offset);
2084 else
2085 err = strbuf_addf(buf, "%+ld(", ref->offset);
2086 return (err < 0) ? err : depth;
2087 }
2088
synthesize_probe_trace_arg(struct probe_trace_arg * arg,struct strbuf * buf)2089 static int synthesize_probe_trace_arg(struct probe_trace_arg *arg,
2090 struct strbuf *buf)
2091 {
2092 struct probe_trace_arg_ref *ref = arg->ref;
2093 int depth = 0, err;
2094
2095 /* Argument name or separator */
2096 if (arg->name)
2097 err = strbuf_addf(buf, " %s=", arg->name);
2098 else
2099 err = strbuf_addch(buf, ' ');
2100 if (err)
2101 return err;
2102
2103 /* Special case: @XXX */
2104 if (arg->value[0] == '@' && arg->ref)
2105 ref = ref->next;
2106
2107 /* Dereferencing arguments */
2108 if (ref) {
2109 depth = __synthesize_probe_trace_arg_ref(ref, buf, 1);
2110 if (depth < 0)
2111 return depth;
2112 }
2113
2114 /* Print argument value */
2115 if (arg->value[0] == '@' && arg->ref)
2116 err = strbuf_addf(buf, "%s%+ld", arg->value, arg->ref->offset);
2117 else
2118 err = strbuf_addstr(buf, arg->value);
2119
2120 /* Closing */
2121 while (!err && depth--)
2122 err = strbuf_addch(buf, ')');
2123
2124 /* Print argument type */
2125 if (!err && arg->type)
2126 err = strbuf_addf(buf, ":%s", arg->type);
2127
2128 return err;
2129 }
2130
2131 static int
synthesize_probe_trace_args(struct probe_trace_event * tev,struct strbuf * buf)2132 synthesize_probe_trace_args(struct probe_trace_event *tev, struct strbuf *buf)
2133 {
2134 int i, ret = 0;
2135
2136 for (i = 0; i < tev->nargs && ret >= 0; i++)
2137 ret = synthesize_probe_trace_arg(&tev->args[i], buf);
2138
2139 return ret;
2140 }
2141
2142 static int
synthesize_uprobe_trace_def(struct probe_trace_point * tp,struct strbuf * buf)2143 synthesize_uprobe_trace_def(struct probe_trace_point *tp, struct strbuf *buf)
2144 {
2145 int err;
2146
2147 /* Uprobes must have tp->module */
2148 if (!tp->module)
2149 return -EINVAL;
2150 /*
2151 * If tp->address == 0, then this point must be a
2152 * absolute address uprobe.
2153 * try_to_find_absolute_address() should have made
2154 * tp->symbol to "0x0".
2155 */
2156 if (!tp->address && (!tp->symbol || strcmp(tp->symbol, "0x0")))
2157 return -EINVAL;
2158
2159 /* Use the tp->address for uprobes */
2160 err = strbuf_addf(buf, "%s:0x%" PRIx64, tp->module, tp->address);
2161
2162 if (err >= 0 && tp->ref_ctr_offset) {
2163 if (!uprobe_ref_ctr_is_supported())
2164 return -EINVAL;
2165 err = strbuf_addf(buf, "(0x%lx)", tp->ref_ctr_offset);
2166 }
2167 return err >= 0 ? 0 : err;
2168 }
2169
2170 static int
synthesize_kprobe_trace_def(struct probe_trace_point * tp,struct strbuf * buf)2171 synthesize_kprobe_trace_def(struct probe_trace_point *tp, struct strbuf *buf)
2172 {
2173 if (!strncmp(tp->symbol, "0x", 2)) {
2174 /* Absolute address. See try_to_find_absolute_address() */
2175 return strbuf_addf(buf, "%s%s0x%" PRIx64, tp->module ?: "",
2176 tp->module ? ":" : "", tp->address);
2177 } else {
2178 return strbuf_addf(buf, "%s%s%s+%lu", tp->module ?: "",
2179 tp->module ? ":" : "", tp->symbol, tp->offset);
2180 }
2181 }
2182
synthesize_probe_trace_command(struct probe_trace_event * tev)2183 char *synthesize_probe_trace_command(struct probe_trace_event *tev)
2184 {
2185 struct probe_trace_point *tp = &tev->point;
2186 struct strbuf buf;
2187 char *ret = NULL;
2188 int err;
2189
2190 if (strbuf_init(&buf, 32) < 0)
2191 return NULL;
2192
2193 if (strbuf_addf(&buf, "%c:%s/%s ", tp->retprobe ? 'r' : 'p',
2194 tev->group, tev->event) < 0)
2195 goto error;
2196
2197 if (tev->uprobes)
2198 err = synthesize_uprobe_trace_def(tp, &buf);
2199 else
2200 err = synthesize_kprobe_trace_def(tp, &buf);
2201
2202 if (err >= 0)
2203 err = synthesize_probe_trace_args(tev, &buf);
2204
2205 if (err >= 0)
2206 ret = strbuf_detach(&buf, NULL);
2207 error:
2208 strbuf_release(&buf);
2209 return ret;
2210 }
2211
find_perf_probe_point_from_map(struct probe_trace_point * tp,struct perf_probe_point * pp,bool is_kprobe)2212 static int find_perf_probe_point_from_map(struct probe_trace_point *tp,
2213 struct perf_probe_point *pp,
2214 bool is_kprobe)
2215 {
2216 struct symbol *sym = NULL;
2217 struct map *map = NULL;
2218 u64 addr = tp->address;
2219 int ret = -ENOENT;
2220
2221 if (!is_kprobe) {
2222 map = dso__new_map(tp->module);
2223 if (!map)
2224 goto out;
2225 sym = map__find_symbol(map, addr);
2226 } else {
2227 if (tp->symbol && !addr) {
2228 if (kernel_get_symbol_address_by_name(tp->symbol,
2229 &addr, true, false) < 0)
2230 goto out;
2231 }
2232 if (addr) {
2233 addr += tp->offset;
2234 sym = machine__find_kernel_symbol(host_machine, addr, &map);
2235 }
2236 }
2237
2238 if (!sym)
2239 goto out;
2240
2241 pp->retprobe = tp->retprobe;
2242 pp->offset = addr - map->unmap_ip(map, sym->start);
2243 pp->function = strdup(sym->name);
2244 ret = pp->function ? 0 : -ENOMEM;
2245
2246 out:
2247 if (map && !is_kprobe) {
2248 map__put(map);
2249 }
2250
2251 return ret;
2252 }
2253
convert_to_perf_probe_point(struct probe_trace_point * tp,struct perf_probe_point * pp,bool is_kprobe)2254 static int convert_to_perf_probe_point(struct probe_trace_point *tp,
2255 struct perf_probe_point *pp,
2256 bool is_kprobe)
2257 {
2258 char buf[128];
2259 int ret;
2260
2261 ret = find_perf_probe_point_from_dwarf(tp, pp, is_kprobe);
2262 if (!ret)
2263 return 0;
2264 ret = find_perf_probe_point_from_map(tp, pp, is_kprobe);
2265 if (!ret)
2266 return 0;
2267
2268 pr_debug("Failed to find probe point from both of dwarf and map.\n");
2269
2270 if (tp->symbol) {
2271 pp->function = strdup(tp->symbol);
2272 pp->offset = tp->offset;
2273 } else {
2274 ret = e_snprintf(buf, 128, "0x%" PRIx64, tp->address);
2275 if (ret < 0)
2276 return ret;
2277 pp->function = strdup(buf);
2278 pp->offset = 0;
2279 }
2280 if (pp->function == NULL)
2281 return -ENOMEM;
2282
2283 pp->retprobe = tp->retprobe;
2284
2285 return 0;
2286 }
2287
convert_to_perf_probe_event(struct probe_trace_event * tev,struct perf_probe_event * pev,bool is_kprobe)2288 static int convert_to_perf_probe_event(struct probe_trace_event *tev,
2289 struct perf_probe_event *pev, bool is_kprobe)
2290 {
2291 struct strbuf buf = STRBUF_INIT;
2292 int i, ret;
2293
2294 /* Convert event/group name */
2295 pev->event = strdup(tev->event);
2296 pev->group = strdup(tev->group);
2297 if (pev->event == NULL || pev->group == NULL)
2298 return -ENOMEM;
2299
2300 /* Convert trace_point to probe_point */
2301 ret = convert_to_perf_probe_point(&tev->point, &pev->point, is_kprobe);
2302 if (ret < 0)
2303 return ret;
2304
2305 /* Convert trace_arg to probe_arg */
2306 pev->nargs = tev->nargs;
2307 pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs);
2308 if (pev->args == NULL)
2309 return -ENOMEM;
2310 for (i = 0; i < tev->nargs && ret >= 0; i++) {
2311 if (tev->args[i].name)
2312 pev->args[i].name = strdup(tev->args[i].name);
2313 else {
2314 if ((ret = strbuf_init(&buf, 32)) < 0)
2315 goto error;
2316 ret = synthesize_probe_trace_arg(&tev->args[i], &buf);
2317 pev->args[i].name = strbuf_detach(&buf, NULL);
2318 }
2319 if (pev->args[i].name == NULL && ret >= 0)
2320 ret = -ENOMEM;
2321 }
2322 error:
2323 if (ret < 0)
2324 clear_perf_probe_event(pev);
2325
2326 return ret;
2327 }
2328
clear_perf_probe_event(struct perf_probe_event * pev)2329 void clear_perf_probe_event(struct perf_probe_event *pev)
2330 {
2331 struct perf_probe_arg_field *field, *next;
2332 int i;
2333
2334 zfree(&pev->event);
2335 zfree(&pev->group);
2336 zfree(&pev->target);
2337 clear_perf_probe_point(&pev->point);
2338
2339 for (i = 0; i < pev->nargs; i++) {
2340 zfree(&pev->args[i].name);
2341 zfree(&pev->args[i].var);
2342 zfree(&pev->args[i].type);
2343 field = pev->args[i].field;
2344 while (field) {
2345 next = field->next;
2346 zfree(&field->name);
2347 free(field);
2348 field = next;
2349 }
2350 }
2351 pev->nargs = 0;
2352 zfree(&pev->args);
2353 }
2354
2355 #define strdup_or_goto(str, label) \
2356 ({ char *__p = NULL; if (str && !(__p = strdup(str))) goto label; __p; })
2357
perf_probe_point__copy(struct perf_probe_point * dst,struct perf_probe_point * src)2358 static int perf_probe_point__copy(struct perf_probe_point *dst,
2359 struct perf_probe_point *src)
2360 {
2361 dst->file = strdup_or_goto(src->file, out_err);
2362 dst->function = strdup_or_goto(src->function, out_err);
2363 dst->lazy_line = strdup_or_goto(src->lazy_line, out_err);
2364 dst->line = src->line;
2365 dst->retprobe = src->retprobe;
2366 dst->offset = src->offset;
2367 return 0;
2368
2369 out_err:
2370 clear_perf_probe_point(dst);
2371 return -ENOMEM;
2372 }
2373
perf_probe_arg__copy(struct perf_probe_arg * dst,struct perf_probe_arg * src)2374 static int perf_probe_arg__copy(struct perf_probe_arg *dst,
2375 struct perf_probe_arg *src)
2376 {
2377 struct perf_probe_arg_field *field, **ppfield;
2378
2379 dst->name = strdup_or_goto(src->name, out_err);
2380 dst->var = strdup_or_goto(src->var, out_err);
2381 dst->type = strdup_or_goto(src->type, out_err);
2382
2383 field = src->field;
2384 ppfield = &(dst->field);
2385 while (field) {
2386 *ppfield = zalloc(sizeof(*field));
2387 if (!*ppfield)
2388 goto out_err;
2389 (*ppfield)->name = strdup_or_goto(field->name, out_err);
2390 (*ppfield)->index = field->index;
2391 (*ppfield)->ref = field->ref;
2392 field = field->next;
2393 ppfield = &((*ppfield)->next);
2394 }
2395 return 0;
2396 out_err:
2397 return -ENOMEM;
2398 }
2399
perf_probe_event__copy(struct perf_probe_event * dst,struct perf_probe_event * src)2400 int perf_probe_event__copy(struct perf_probe_event *dst,
2401 struct perf_probe_event *src)
2402 {
2403 int i;
2404
2405 dst->event = strdup_or_goto(src->event, out_err);
2406 dst->group = strdup_or_goto(src->group, out_err);
2407 dst->target = strdup_or_goto(src->target, out_err);
2408 dst->uprobes = src->uprobes;
2409
2410 if (perf_probe_point__copy(&dst->point, &src->point) < 0)
2411 goto out_err;
2412
2413 dst->args = zalloc(sizeof(struct perf_probe_arg) * src->nargs);
2414 if (!dst->args)
2415 goto out_err;
2416 dst->nargs = src->nargs;
2417
2418 for (i = 0; i < src->nargs; i++)
2419 if (perf_probe_arg__copy(&dst->args[i], &src->args[i]) < 0)
2420 goto out_err;
2421 return 0;
2422
2423 out_err:
2424 clear_perf_probe_event(dst);
2425 return -ENOMEM;
2426 }
2427
clear_probe_trace_event(struct probe_trace_event * tev)2428 void clear_probe_trace_event(struct probe_trace_event *tev)
2429 {
2430 struct probe_trace_arg_ref *ref, *next;
2431 int i;
2432
2433 zfree(&tev->event);
2434 zfree(&tev->group);
2435 zfree(&tev->point.symbol);
2436 zfree(&tev->point.realname);
2437 zfree(&tev->point.module);
2438 for (i = 0; i < tev->nargs; i++) {
2439 zfree(&tev->args[i].name);
2440 zfree(&tev->args[i].value);
2441 zfree(&tev->args[i].type);
2442 ref = tev->args[i].ref;
2443 while (ref) {
2444 next = ref->next;
2445 free(ref);
2446 ref = next;
2447 }
2448 }
2449 zfree(&tev->args);
2450 tev->nargs = 0;
2451 }
2452
2453 struct kprobe_blacklist_node {
2454 struct list_head list;
2455 u64 start;
2456 u64 end;
2457 char *symbol;
2458 };
2459
kprobe_blacklist__delete(struct list_head * blacklist)2460 static void kprobe_blacklist__delete(struct list_head *blacklist)
2461 {
2462 struct kprobe_blacklist_node *node;
2463
2464 while (!list_empty(blacklist)) {
2465 node = list_first_entry(blacklist,
2466 struct kprobe_blacklist_node, list);
2467 list_del_init(&node->list);
2468 zfree(&node->symbol);
2469 free(node);
2470 }
2471 }
2472
kprobe_blacklist__load(struct list_head * blacklist)2473 static int kprobe_blacklist__load(struct list_head *blacklist)
2474 {
2475 struct kprobe_blacklist_node *node;
2476 const char *__debugfs = debugfs__mountpoint();
2477 char buf[PATH_MAX], *p;
2478 FILE *fp;
2479 int ret;
2480
2481 if (__debugfs == NULL)
2482 return -ENOTSUP;
2483
2484 ret = e_snprintf(buf, PATH_MAX, "%s/kprobes/blacklist", __debugfs);
2485 if (ret < 0)
2486 return ret;
2487
2488 fp = fopen(buf, "r");
2489 if (!fp)
2490 return -errno;
2491
2492 ret = 0;
2493 while (fgets(buf, PATH_MAX, fp)) {
2494 node = zalloc(sizeof(*node));
2495 if (!node) {
2496 ret = -ENOMEM;
2497 break;
2498 }
2499 INIT_LIST_HEAD(&node->list);
2500 list_add_tail(&node->list, blacklist);
2501 if (sscanf(buf, "0x%" PRIx64 "-0x%" PRIx64, &node->start, &node->end) != 2) {
2502 ret = -EINVAL;
2503 break;
2504 }
2505 p = strchr(buf, '\t');
2506 if (p) {
2507 p++;
2508 if (p[strlen(p) - 1] == '\n')
2509 p[strlen(p) - 1] = '\0';
2510 } else
2511 p = (char *)"unknown";
2512 node->symbol = strdup(p);
2513 if (!node->symbol) {
2514 ret = -ENOMEM;
2515 break;
2516 }
2517 pr_debug2("Blacklist: 0x%" PRIx64 "-0x%" PRIx64 ", %s\n",
2518 node->start, node->end, node->symbol);
2519 ret++;
2520 }
2521 if (ret < 0)
2522 kprobe_blacklist__delete(blacklist);
2523 fclose(fp);
2524
2525 return ret;
2526 }
2527
2528 static struct kprobe_blacklist_node *
kprobe_blacklist__find_by_address(struct list_head * blacklist,u64 address)2529 kprobe_blacklist__find_by_address(struct list_head *blacklist, u64 address)
2530 {
2531 struct kprobe_blacklist_node *node;
2532
2533 list_for_each_entry(node, blacklist, list) {
2534 if (node->start <= address && address < node->end)
2535 return node;
2536 }
2537
2538 return NULL;
2539 }
2540
2541 static LIST_HEAD(kprobe_blacklist);
2542
kprobe_blacklist__init(void)2543 static void kprobe_blacklist__init(void)
2544 {
2545 if (!list_empty(&kprobe_blacklist))
2546 return;
2547
2548 if (kprobe_blacklist__load(&kprobe_blacklist) < 0)
2549 pr_debug("No kprobe blacklist support, ignored\n");
2550 }
2551
kprobe_blacklist__release(void)2552 static void kprobe_blacklist__release(void)
2553 {
2554 kprobe_blacklist__delete(&kprobe_blacklist);
2555 }
2556
kprobe_blacklist__listed(u64 address)2557 static bool kprobe_blacklist__listed(u64 address)
2558 {
2559 return !!kprobe_blacklist__find_by_address(&kprobe_blacklist, address);
2560 }
2561
perf_probe_event__sprintf(const char * group,const char * event,struct perf_probe_event * pev,const char * module,struct strbuf * result)2562 static int perf_probe_event__sprintf(const char *group, const char *event,
2563 struct perf_probe_event *pev,
2564 const char *module,
2565 struct strbuf *result)
2566 {
2567 int i, ret;
2568 char *buf;
2569
2570 if (asprintf(&buf, "%s:%s", group, event) < 0)
2571 return -errno;
2572 ret = strbuf_addf(result, " %-20s (on ", buf);
2573 free(buf);
2574 if (ret)
2575 return ret;
2576
2577 /* Synthesize only event probe point */
2578 buf = synthesize_perf_probe_point(&pev->point);
2579 if (!buf)
2580 return -ENOMEM;
2581 ret = strbuf_addstr(result, buf);
2582 free(buf);
2583
2584 if (!ret && module)
2585 ret = strbuf_addf(result, " in %s", module);
2586
2587 if (!ret && pev->nargs > 0) {
2588 ret = strbuf_add(result, " with", 5);
2589 for (i = 0; !ret && i < pev->nargs; i++) {
2590 buf = synthesize_perf_probe_arg(&pev->args[i]);
2591 if (!buf)
2592 return -ENOMEM;
2593 ret = strbuf_addf(result, " %s", buf);
2594 free(buf);
2595 }
2596 }
2597 if (!ret)
2598 ret = strbuf_addch(result, ')');
2599
2600 return ret;
2601 }
2602
2603 /* Show an event */
show_perf_probe_event(const char * group,const char * event,struct perf_probe_event * pev,const char * module,bool use_stdout)2604 int show_perf_probe_event(const char *group, const char *event,
2605 struct perf_probe_event *pev,
2606 const char *module, bool use_stdout)
2607 {
2608 struct strbuf buf = STRBUF_INIT;
2609 int ret;
2610
2611 ret = perf_probe_event__sprintf(group, event, pev, module, &buf);
2612 if (ret >= 0) {
2613 if (use_stdout)
2614 printf("%s\n", buf.buf);
2615 else
2616 pr_info("%s\n", buf.buf);
2617 }
2618 strbuf_release(&buf);
2619
2620 return ret;
2621 }
2622
filter_probe_trace_event(struct probe_trace_event * tev,struct strfilter * filter)2623 static bool filter_probe_trace_event(struct probe_trace_event *tev,
2624 struct strfilter *filter)
2625 {
2626 char tmp[128];
2627
2628 /* At first, check the event name itself */
2629 if (strfilter__compare(filter, tev->event))
2630 return true;
2631
2632 /* Next, check the combination of name and group */
2633 if (e_snprintf(tmp, 128, "%s:%s", tev->group, tev->event) < 0)
2634 return false;
2635 return strfilter__compare(filter, tmp);
2636 }
2637
__show_perf_probe_events(int fd,bool is_kprobe,struct strfilter * filter)2638 static int __show_perf_probe_events(int fd, bool is_kprobe,
2639 struct strfilter *filter)
2640 {
2641 int ret = 0;
2642 struct probe_trace_event tev;
2643 struct perf_probe_event pev;
2644 struct strlist *rawlist;
2645 struct str_node *ent;
2646
2647 memset(&tev, 0, sizeof(tev));
2648 memset(&pev, 0, sizeof(pev));
2649
2650 rawlist = probe_file__get_rawlist(fd);
2651 if (!rawlist)
2652 return -ENOMEM;
2653
2654 strlist__for_each_entry(ent, rawlist) {
2655 ret = parse_probe_trace_command(ent->s, &tev);
2656 if (ret >= 0) {
2657 if (!filter_probe_trace_event(&tev, filter))
2658 goto next;
2659 ret = convert_to_perf_probe_event(&tev, &pev,
2660 is_kprobe);
2661 if (ret < 0)
2662 goto next;
2663 ret = show_perf_probe_event(pev.group, pev.event,
2664 &pev, tev.point.module,
2665 true);
2666 }
2667 next:
2668 clear_perf_probe_event(&pev);
2669 clear_probe_trace_event(&tev);
2670 if (ret < 0)
2671 break;
2672 }
2673 strlist__delete(rawlist);
2674 /* Cleanup cached debuginfo if needed */
2675 debuginfo_cache__exit();
2676
2677 return ret;
2678 }
2679
2680 /* List up current perf-probe events */
show_perf_probe_events(struct strfilter * filter)2681 int show_perf_probe_events(struct strfilter *filter)
2682 {
2683 int kp_fd, up_fd, ret;
2684
2685 setup_pager();
2686
2687 if (probe_conf.cache)
2688 return probe_cache__show_all_caches(filter);
2689
2690 ret = init_probe_symbol_maps(false);
2691 if (ret < 0)
2692 return ret;
2693
2694 ret = probe_file__open_both(&kp_fd, &up_fd, 0);
2695 if (ret < 0)
2696 return ret;
2697
2698 if (kp_fd >= 0)
2699 ret = __show_perf_probe_events(kp_fd, true, filter);
2700 if (up_fd >= 0 && ret >= 0)
2701 ret = __show_perf_probe_events(up_fd, false, filter);
2702 if (kp_fd > 0)
2703 close(kp_fd);
2704 if (up_fd > 0)
2705 close(up_fd);
2706 exit_probe_symbol_maps();
2707
2708 return ret;
2709 }
2710
get_new_event_name(char * buf,size_t len,const char * base,struct strlist * namelist,bool ret_event,bool allow_suffix)2711 static int get_new_event_name(char *buf, size_t len, const char *base,
2712 struct strlist *namelist, bool ret_event,
2713 bool allow_suffix)
2714 {
2715 int i, ret;
2716 char *p, *nbase;
2717
2718 if (*base == '.')
2719 base++;
2720 nbase = strdup(base);
2721 if (!nbase)
2722 return -ENOMEM;
2723
2724 /* Cut off the dot suffixes (e.g. .const, .isra) and version suffixes */
2725 p = strpbrk(nbase, ".@");
2726 if (p && p != nbase)
2727 *p = '\0';
2728
2729 /* Try no suffix number */
2730 ret = e_snprintf(buf, len, "%s%s", nbase, ret_event ? "__return" : "");
2731 if (ret < 0) {
2732 pr_debug("snprintf() failed: %d\n", ret);
2733 goto out;
2734 }
2735 if (!strlist__has_entry(namelist, buf))
2736 goto out;
2737
2738 if (!allow_suffix) {
2739 pr_warning("Error: event \"%s\" already exists.\n"
2740 " Hint: Remove existing event by 'perf probe -d'\n"
2741 " or force duplicates by 'perf probe -f'\n"
2742 " or set 'force=yes' in BPF source.\n",
2743 buf);
2744 ret = -EEXIST;
2745 goto out;
2746 }
2747
2748 /* Try to add suffix */
2749 for (i = 1; i < MAX_EVENT_INDEX; i++) {
2750 ret = e_snprintf(buf, len, "%s_%d", nbase, i);
2751 if (ret < 0) {
2752 pr_debug("snprintf() failed: %d\n", ret);
2753 goto out;
2754 }
2755 if (!strlist__has_entry(namelist, buf))
2756 break;
2757 }
2758 if (i == MAX_EVENT_INDEX) {
2759 pr_warning("Too many events are on the same function.\n");
2760 ret = -ERANGE;
2761 }
2762
2763 out:
2764 free(nbase);
2765
2766 /* Final validation */
2767 if (ret >= 0 && !is_c_func_name(buf)) {
2768 pr_warning("Internal error: \"%s\" is an invalid event name.\n",
2769 buf);
2770 ret = -EINVAL;
2771 }
2772
2773 return ret;
2774 }
2775
2776 /* Warn if the current kernel's uprobe implementation is old */
warn_uprobe_event_compat(struct probe_trace_event * tev)2777 static void warn_uprobe_event_compat(struct probe_trace_event *tev)
2778 {
2779 int i;
2780 char *buf = synthesize_probe_trace_command(tev);
2781 struct probe_trace_point *tp = &tev->point;
2782
2783 if (tp->ref_ctr_offset && !uprobe_ref_ctr_is_supported()) {
2784 pr_warning("A semaphore is associated with %s:%s and "
2785 "seems your kernel doesn't support it.\n",
2786 tev->group, tev->event);
2787 }
2788
2789 /* Old uprobe event doesn't support memory dereference */
2790 if (!tev->uprobes || tev->nargs == 0 || !buf)
2791 goto out;
2792
2793 for (i = 0; i < tev->nargs; i++)
2794 if (strglobmatch(tev->args[i].value, "[$@+-]*")) {
2795 pr_warning("Please upgrade your kernel to at least "
2796 "3.14 to have access to feature %s\n",
2797 tev->args[i].value);
2798 break;
2799 }
2800 out:
2801 free(buf);
2802 }
2803
2804 /* Set new name from original perf_probe_event and namelist */
probe_trace_event__set_name(struct probe_trace_event * tev,struct perf_probe_event * pev,struct strlist * namelist,bool allow_suffix)2805 static int probe_trace_event__set_name(struct probe_trace_event *tev,
2806 struct perf_probe_event *pev,
2807 struct strlist *namelist,
2808 bool allow_suffix)
2809 {
2810 const char *event, *group;
2811 char buf[64];
2812 int ret;
2813
2814 /* If probe_event or trace_event already have the name, reuse it */
2815 if (pev->event && !pev->sdt)
2816 event = pev->event;
2817 else if (tev->event)
2818 event = tev->event;
2819 else {
2820 /* Or generate new one from probe point */
2821 if (pev->point.function &&
2822 (strncmp(pev->point.function, "0x", 2) != 0) &&
2823 !strisglob(pev->point.function))
2824 event = pev->point.function;
2825 else
2826 event = tev->point.realname;
2827 }
2828 if (pev->group && !pev->sdt)
2829 group = pev->group;
2830 else if (tev->group)
2831 group = tev->group;
2832 else
2833 group = PERFPROBE_GROUP;
2834
2835 /* Get an unused new event name */
2836 ret = get_new_event_name(buf, 64, event, namelist,
2837 tev->point.retprobe, allow_suffix);
2838 if (ret < 0)
2839 return ret;
2840
2841 event = buf;
2842
2843 tev->event = strdup(event);
2844 tev->group = strdup(group);
2845 if (tev->event == NULL || tev->group == NULL)
2846 return -ENOMEM;
2847
2848 /*
2849 * Add new event name to namelist if multiprobe event is NOT
2850 * supported, since we have to use new event name for following
2851 * probes in that case.
2852 */
2853 if (!multiprobe_event_is_supported())
2854 strlist__add(namelist, event);
2855 return 0;
2856 }
2857
__open_probe_file_and_namelist(bool uprobe,struct strlist ** namelist)2858 static int __open_probe_file_and_namelist(bool uprobe,
2859 struct strlist **namelist)
2860 {
2861 int fd;
2862
2863 fd = probe_file__open(PF_FL_RW | (uprobe ? PF_FL_UPROBE : 0));
2864 if (fd < 0)
2865 return fd;
2866
2867 /* Get current event names */
2868 *namelist = probe_file__get_namelist(fd);
2869 if (!(*namelist)) {
2870 pr_debug("Failed to get current event list.\n");
2871 close(fd);
2872 return -ENOMEM;
2873 }
2874 return fd;
2875 }
2876
__add_probe_trace_events(struct perf_probe_event * pev,struct probe_trace_event * tevs,int ntevs,bool allow_suffix)2877 static int __add_probe_trace_events(struct perf_probe_event *pev,
2878 struct probe_trace_event *tevs,
2879 int ntevs, bool allow_suffix)
2880 {
2881 int i, fd[2] = {-1, -1}, up, ret;
2882 struct probe_trace_event *tev = NULL;
2883 struct probe_cache *cache = NULL;
2884 struct strlist *namelist[2] = {NULL, NULL};
2885 struct nscookie nsc;
2886
2887 up = pev->uprobes ? 1 : 0;
2888 fd[up] = __open_probe_file_and_namelist(up, &namelist[up]);
2889 if (fd[up] < 0)
2890 return fd[up];
2891
2892 ret = 0;
2893 for (i = 0; i < ntevs; i++) {
2894 tev = &tevs[i];
2895 up = tev->uprobes ? 1 : 0;
2896 if (fd[up] == -1) { /* Open the kprobe/uprobe_events */
2897 fd[up] = __open_probe_file_and_namelist(up,
2898 &namelist[up]);
2899 if (fd[up] < 0)
2900 goto close_out;
2901 }
2902 /* Skip if the symbol is out of .text or blacklisted */
2903 if (!tev->point.symbol && !pev->uprobes)
2904 continue;
2905
2906 /* Set new name for tev (and update namelist) */
2907 ret = probe_trace_event__set_name(tev, pev, namelist[up],
2908 allow_suffix);
2909 if (ret < 0)
2910 break;
2911
2912 nsinfo__mountns_enter(pev->nsi, &nsc);
2913 ret = probe_file__add_event(fd[up], tev);
2914 nsinfo__mountns_exit(&nsc);
2915 if (ret < 0)
2916 break;
2917
2918 /*
2919 * Probes after the first probe which comes from same
2920 * user input are always allowed to add suffix, because
2921 * there might be several addresses corresponding to
2922 * one code line.
2923 */
2924 allow_suffix = true;
2925 }
2926 if (ret == -EINVAL && pev->uprobes)
2927 warn_uprobe_event_compat(tev);
2928 if (ret == 0 && probe_conf.cache) {
2929 cache = probe_cache__new(pev->target, pev->nsi);
2930 if (!cache ||
2931 probe_cache__add_entry(cache, pev, tevs, ntevs) < 0 ||
2932 probe_cache__commit(cache) < 0)
2933 pr_warning("Failed to add event to probe cache\n");
2934 probe_cache__delete(cache);
2935 }
2936
2937 close_out:
2938 for (up = 0; up < 2; up++) {
2939 strlist__delete(namelist[up]);
2940 if (fd[up] >= 0)
2941 close(fd[up]);
2942 }
2943 return ret;
2944 }
2945
find_probe_functions(struct map * map,char * name,struct symbol ** syms)2946 static int find_probe_functions(struct map *map, char *name,
2947 struct symbol **syms)
2948 {
2949 int found = 0;
2950 struct symbol *sym;
2951 struct rb_node *tmp;
2952 const char *norm, *ver;
2953 char *buf = NULL;
2954 bool cut_version = true;
2955
2956 if (map__load(map) < 0)
2957 return -EACCES; /* Possible permission error to load symbols */
2958
2959 /* If user gives a version, don't cut off the version from symbols */
2960 if (strchr(name, '@'))
2961 cut_version = false;
2962
2963 map__for_each_symbol(map, sym, tmp) {
2964 norm = arch__normalize_symbol_name(sym->name);
2965 if (!norm)
2966 continue;
2967
2968 if (cut_version) {
2969 /* We don't care about default symbol or not */
2970 ver = strchr(norm, '@');
2971 if (ver) {
2972 buf = strndup(norm, ver - norm);
2973 if (!buf)
2974 return -ENOMEM;
2975 norm = buf;
2976 }
2977 }
2978
2979 if (strglobmatch(norm, name)) {
2980 found++;
2981 if (syms && found < probe_conf.max_probes)
2982 syms[found - 1] = sym;
2983 }
2984 if (buf)
2985 zfree(&buf);
2986 }
2987
2988 return found;
2989 }
2990
arch__fix_tev_from_maps(struct perf_probe_event * pev __maybe_unused,struct probe_trace_event * tev __maybe_unused,struct map * map __maybe_unused,struct symbol * sym __maybe_unused)2991 void __weak arch__fix_tev_from_maps(struct perf_probe_event *pev __maybe_unused,
2992 struct probe_trace_event *tev __maybe_unused,
2993 struct map *map __maybe_unused,
2994 struct symbol *sym __maybe_unused) { }
2995
2996
pr_kallsyms_access_error(void)2997 static void pr_kallsyms_access_error(void)
2998 {
2999 pr_err("Please ensure you can read the /proc/kallsyms symbol addresses.\n"
3000 "If /proc/sys/kernel/kptr_restrict is '2', you can not read\n"
3001 "kernel symbol addresses even if you are a superuser. Please change\n"
3002 "it to '1'. If kptr_restrict is '1', the superuser can read the\n"
3003 "symbol addresses.\n"
3004 "In that case, please run this command again with sudo.\n");
3005 }
3006
3007 /*
3008 * Find probe function addresses from map.
3009 * Return an error or the number of found probe_trace_event
3010 */
find_probe_trace_events_from_map(struct perf_probe_event * pev,struct probe_trace_event ** tevs)3011 static int find_probe_trace_events_from_map(struct perf_probe_event *pev,
3012 struct probe_trace_event **tevs)
3013 {
3014 struct map *map = NULL;
3015 struct ref_reloc_sym *reloc_sym = NULL;
3016 struct symbol *sym;
3017 struct symbol **syms = NULL;
3018 struct probe_trace_event *tev;
3019 struct perf_probe_point *pp = &pev->point;
3020 struct probe_trace_point *tp;
3021 int num_matched_functions;
3022 int ret, i, j, skipped = 0;
3023 char *mod_name;
3024
3025 map = get_target_map(pev->target, pev->nsi, pev->uprobes);
3026 if (!map) {
3027 ret = -EINVAL;
3028 goto out;
3029 }
3030
3031 syms = malloc(sizeof(struct symbol *) * probe_conf.max_probes);
3032 if (!syms) {
3033 ret = -ENOMEM;
3034 goto out;
3035 }
3036
3037 /*
3038 * Load matched symbols: Since the different local symbols may have
3039 * same name but different addresses, this lists all the symbols.
3040 */
3041 num_matched_functions = find_probe_functions(map, pp->function, syms);
3042 if (num_matched_functions <= 0) {
3043 if (num_matched_functions == -EACCES) {
3044 pr_err("Failed to load symbols from %s\n",
3045 pev->target ?: "/proc/kallsyms");
3046 if (pev->target)
3047 pr_err("Please ensure the file is not stripped.\n");
3048 else
3049 pr_kallsyms_access_error();
3050 } else
3051 pr_err("Failed to find symbol %s in %s\n", pp->function,
3052 pev->target ? : "kernel");
3053 ret = -ENOENT;
3054 goto out;
3055 } else if (num_matched_functions > probe_conf.max_probes) {
3056 pr_err("Too many functions matched in %s\n",
3057 pev->target ? : "kernel");
3058 ret = -E2BIG;
3059 goto out;
3060 }
3061
3062 /* Note that the symbols in the kmodule are not relocated */
3063 if (!pev->uprobes && !pev->target &&
3064 (!pp->retprobe || kretprobe_offset_is_supported())) {
3065 reloc_sym = kernel_get_ref_reloc_sym(NULL);
3066 if (!reloc_sym) {
3067 pr_warning("Relocated base symbol is not found! "
3068 "Check /proc/sys/kernel/kptr_restrict\n"
3069 "and /proc/sys/kernel/perf_event_paranoid. "
3070 "Or run as privileged perf user.\n\n");
3071 ret = -EINVAL;
3072 goto out;
3073 }
3074 }
3075
3076 /* Setup result trace-probe-events */
3077 *tevs = zalloc(sizeof(*tev) * num_matched_functions);
3078 if (!*tevs) {
3079 ret = -ENOMEM;
3080 goto out;
3081 }
3082
3083 ret = 0;
3084
3085 for (j = 0; j < num_matched_functions; j++) {
3086 sym = syms[j];
3087
3088 if (sym->type != STT_FUNC)
3089 continue;
3090
3091 /* There can be duplicated symbols in the map */
3092 for (i = 0; i < j; i++)
3093 if (sym->start == syms[i]->start) {
3094 pr_debug("Found duplicated symbol %s @ %" PRIx64 "\n",
3095 sym->name, sym->start);
3096 break;
3097 }
3098 if (i != j)
3099 continue;
3100
3101 tev = (*tevs) + ret;
3102 tp = &tev->point;
3103 if (ret == num_matched_functions) {
3104 pr_warning("Too many symbols are listed. Skip it.\n");
3105 break;
3106 }
3107 ret++;
3108
3109 if (pp->offset > sym->end - sym->start) {
3110 pr_warning("Offset %ld is bigger than the size of %s\n",
3111 pp->offset, sym->name);
3112 ret = -ENOENT;
3113 goto err_out;
3114 }
3115 /* Add one probe point */
3116 tp->address = map->unmap_ip(map, sym->start) + pp->offset;
3117
3118 /* Check the kprobe (not in module) is within .text */
3119 if (!pev->uprobes && !pev->target &&
3120 kprobe_warn_out_range(sym->name, tp->address)) {
3121 tp->symbol = NULL; /* Skip it */
3122 skipped++;
3123 } else if (reloc_sym) {
3124 tp->symbol = strdup_or_goto(reloc_sym->name, nomem_out);
3125 tp->offset = tp->address - reloc_sym->addr;
3126 } else {
3127 tp->symbol = strdup_or_goto(sym->name, nomem_out);
3128 tp->offset = pp->offset;
3129 }
3130 tp->realname = strdup_or_goto(sym->name, nomem_out);
3131
3132 tp->retprobe = pp->retprobe;
3133 if (pev->target) {
3134 if (pev->uprobes) {
3135 tev->point.module = strdup_or_goto(pev->target,
3136 nomem_out);
3137 } else {
3138 mod_name = find_module_name(pev->target);
3139 tev->point.module =
3140 strdup(mod_name ? mod_name : pev->target);
3141 free(mod_name);
3142 if (!tev->point.module)
3143 goto nomem_out;
3144 }
3145 }
3146 tev->uprobes = pev->uprobes;
3147 tev->nargs = pev->nargs;
3148 if (tev->nargs) {
3149 tev->args = zalloc(sizeof(struct probe_trace_arg) *
3150 tev->nargs);
3151 if (tev->args == NULL)
3152 goto nomem_out;
3153 }
3154 for (i = 0; i < tev->nargs; i++) {
3155 if (pev->args[i].name)
3156 tev->args[i].name =
3157 strdup_or_goto(pev->args[i].name,
3158 nomem_out);
3159
3160 tev->args[i].value = strdup_or_goto(pev->args[i].var,
3161 nomem_out);
3162 if (pev->args[i].type)
3163 tev->args[i].type =
3164 strdup_or_goto(pev->args[i].type,
3165 nomem_out);
3166 }
3167 arch__fix_tev_from_maps(pev, tev, map, sym);
3168 }
3169 if (ret == skipped) {
3170 ret = -ENOENT;
3171 goto err_out;
3172 }
3173
3174 out:
3175 map__put(map);
3176 free(syms);
3177 return ret;
3178
3179 nomem_out:
3180 ret = -ENOMEM;
3181 err_out:
3182 clear_probe_trace_events(*tevs, num_matched_functions);
3183 zfree(tevs);
3184 goto out;
3185 }
3186
try_to_find_absolute_address(struct perf_probe_event * pev,struct probe_trace_event ** tevs)3187 static int try_to_find_absolute_address(struct perf_probe_event *pev,
3188 struct probe_trace_event **tevs)
3189 {
3190 struct perf_probe_point *pp = &pev->point;
3191 struct probe_trace_event *tev;
3192 struct probe_trace_point *tp;
3193 int i, err;
3194
3195 if (!(pev->point.function && !strncmp(pev->point.function, "0x", 2)))
3196 return -EINVAL;
3197 if (perf_probe_event_need_dwarf(pev))
3198 return -EINVAL;
3199
3200 /*
3201 * This is 'perf probe /lib/libc.so 0xabcd'. Try to probe at
3202 * absolute address.
3203 *
3204 * Only one tev can be generated by this.
3205 */
3206 *tevs = zalloc(sizeof(*tev));
3207 if (!*tevs)
3208 return -ENOMEM;
3209
3210 tev = *tevs;
3211 tp = &tev->point;
3212
3213 /*
3214 * Don't use tp->offset, use address directly, because
3215 * in synthesize_probe_trace_command() address cannot be
3216 * zero.
3217 */
3218 tp->address = pev->point.abs_address;
3219 tp->retprobe = pp->retprobe;
3220 tev->uprobes = pev->uprobes;
3221
3222 err = -ENOMEM;
3223 /*
3224 * Give it a '0x' leading symbol name.
3225 * In __add_probe_trace_events, a NULL symbol is interpreted as
3226 * invalid.
3227 */
3228 if (asprintf(&tp->symbol, "0x%" PRIx64, tp->address) < 0)
3229 goto errout;
3230
3231 /* For kprobe, check range */
3232 if ((!tev->uprobes) &&
3233 (kprobe_warn_out_range(tev->point.symbol,
3234 tev->point.address))) {
3235 err = -EACCES;
3236 goto errout;
3237 }
3238
3239 if (asprintf(&tp->realname, "abs_%" PRIx64, tp->address) < 0)
3240 goto errout;
3241
3242 if (pev->target) {
3243 tp->module = strdup(pev->target);
3244 if (!tp->module)
3245 goto errout;
3246 }
3247
3248 if (tev->group) {
3249 tev->group = strdup(pev->group);
3250 if (!tev->group)
3251 goto errout;
3252 }
3253
3254 if (pev->event) {
3255 tev->event = strdup(pev->event);
3256 if (!tev->event)
3257 goto errout;
3258 }
3259
3260 tev->nargs = pev->nargs;
3261 tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
3262 if (!tev->args)
3263 goto errout;
3264
3265 for (i = 0; i < tev->nargs; i++)
3266 copy_to_probe_trace_arg(&tev->args[i], &pev->args[i]);
3267
3268 return 1;
3269
3270 errout:
3271 clear_probe_trace_events(*tevs, 1);
3272 *tevs = NULL;
3273 return err;
3274 }
3275
3276 /* Concatenate two arrays */
memcat(void * a,size_t sz_a,void * b,size_t sz_b)3277 static void *memcat(void *a, size_t sz_a, void *b, size_t sz_b)
3278 {
3279 void *ret;
3280
3281 ret = malloc(sz_a + sz_b);
3282 if (ret) {
3283 memcpy(ret, a, sz_a);
3284 memcpy(ret + sz_a, b, sz_b);
3285 }
3286 return ret;
3287 }
3288
3289 static int
concat_probe_trace_events(struct probe_trace_event ** tevs,int * ntevs,struct probe_trace_event ** tevs2,int ntevs2)3290 concat_probe_trace_events(struct probe_trace_event **tevs, int *ntevs,
3291 struct probe_trace_event **tevs2, int ntevs2)
3292 {
3293 struct probe_trace_event *new_tevs;
3294 int ret = 0;
3295
3296 if (*ntevs == 0) {
3297 *tevs = *tevs2;
3298 *ntevs = ntevs2;
3299 *tevs2 = NULL;
3300 return 0;
3301 }
3302
3303 if (*ntevs + ntevs2 > probe_conf.max_probes)
3304 ret = -E2BIG;
3305 else {
3306 /* Concatenate the array of probe_trace_event */
3307 new_tevs = memcat(*tevs, (*ntevs) * sizeof(**tevs),
3308 *tevs2, ntevs2 * sizeof(**tevs2));
3309 if (!new_tevs)
3310 ret = -ENOMEM;
3311 else {
3312 free(*tevs);
3313 *tevs = new_tevs;
3314 *ntevs += ntevs2;
3315 }
3316 }
3317 if (ret < 0)
3318 clear_probe_trace_events(*tevs2, ntevs2);
3319 zfree(tevs2);
3320
3321 return ret;
3322 }
3323
3324 /*
3325 * Try to find probe_trace_event from given probe caches. Return the number
3326 * of cached events found, if an error occurs return the error.
3327 */
find_cached_events(struct perf_probe_event * pev,struct probe_trace_event ** tevs,const char * target)3328 static int find_cached_events(struct perf_probe_event *pev,
3329 struct probe_trace_event **tevs,
3330 const char *target)
3331 {
3332 struct probe_cache *cache;
3333 struct probe_cache_entry *entry;
3334 struct probe_trace_event *tmp_tevs = NULL;
3335 int ntevs = 0;
3336 int ret = 0;
3337
3338 cache = probe_cache__new(target, pev->nsi);
3339 /* Return 0 ("not found") if the target has no probe cache. */
3340 if (!cache)
3341 return 0;
3342
3343 for_each_probe_cache_entry(entry, cache) {
3344 /* Skip the cache entry which has no name */
3345 if (!entry->pev.event || !entry->pev.group)
3346 continue;
3347 if ((!pev->group || strglobmatch(entry->pev.group, pev->group)) &&
3348 strglobmatch(entry->pev.event, pev->event)) {
3349 ret = probe_cache_entry__get_event(entry, &tmp_tevs);
3350 if (ret > 0)
3351 ret = concat_probe_trace_events(tevs, &ntevs,
3352 &tmp_tevs, ret);
3353 if (ret < 0)
3354 break;
3355 }
3356 }
3357 probe_cache__delete(cache);
3358 if (ret < 0) {
3359 clear_probe_trace_events(*tevs, ntevs);
3360 zfree(tevs);
3361 } else {
3362 ret = ntevs;
3363 if (ntevs > 0 && target && target[0] == '/')
3364 pev->uprobes = true;
3365 }
3366
3367 return ret;
3368 }
3369
3370 /* Try to find probe_trace_event from all probe caches */
find_cached_events_all(struct perf_probe_event * pev,struct probe_trace_event ** tevs)3371 static int find_cached_events_all(struct perf_probe_event *pev,
3372 struct probe_trace_event **tevs)
3373 {
3374 struct probe_trace_event *tmp_tevs = NULL;
3375 struct strlist *bidlist;
3376 struct str_node *nd;
3377 char *pathname;
3378 int ntevs = 0;
3379 int ret;
3380
3381 /* Get the buildid list of all valid caches */
3382 bidlist = build_id_cache__list_all(true);
3383 if (!bidlist) {
3384 ret = -errno;
3385 pr_debug("Failed to get buildids: %d\n", ret);
3386 return ret;
3387 }
3388
3389 ret = 0;
3390 strlist__for_each_entry(nd, bidlist) {
3391 pathname = build_id_cache__origname(nd->s);
3392 ret = find_cached_events(pev, &tmp_tevs, pathname);
3393 /* In the case of cnt == 0, we just skip it */
3394 if (ret > 0)
3395 ret = concat_probe_trace_events(tevs, &ntevs,
3396 &tmp_tevs, ret);
3397 free(pathname);
3398 if (ret < 0)
3399 break;
3400 }
3401 strlist__delete(bidlist);
3402
3403 if (ret < 0) {
3404 clear_probe_trace_events(*tevs, ntevs);
3405 zfree(tevs);
3406 } else
3407 ret = ntevs;
3408
3409 return ret;
3410 }
3411
find_probe_trace_events_from_cache(struct perf_probe_event * pev,struct probe_trace_event ** tevs)3412 static int find_probe_trace_events_from_cache(struct perf_probe_event *pev,
3413 struct probe_trace_event **tevs)
3414 {
3415 struct probe_cache *cache;
3416 struct probe_cache_entry *entry;
3417 struct probe_trace_event *tev;
3418 struct str_node *node;
3419 int ret, i;
3420
3421 if (pev->sdt) {
3422 /* For SDT/cached events, we use special search functions */
3423 if (!pev->target)
3424 return find_cached_events_all(pev, tevs);
3425 else
3426 return find_cached_events(pev, tevs, pev->target);
3427 }
3428 cache = probe_cache__new(pev->target, pev->nsi);
3429 if (!cache)
3430 return 0;
3431
3432 entry = probe_cache__find(cache, pev);
3433 if (!entry) {
3434 /* SDT must be in the cache */
3435 ret = pev->sdt ? -ENOENT : 0;
3436 goto out;
3437 }
3438
3439 ret = strlist__nr_entries(entry->tevlist);
3440 if (ret > probe_conf.max_probes) {
3441 pr_debug("Too many entries matched in the cache of %s\n",
3442 pev->target ? : "kernel");
3443 ret = -E2BIG;
3444 goto out;
3445 }
3446
3447 *tevs = zalloc(ret * sizeof(*tev));
3448 if (!*tevs) {
3449 ret = -ENOMEM;
3450 goto out;
3451 }
3452
3453 i = 0;
3454 strlist__for_each_entry(node, entry->tevlist) {
3455 tev = &(*tevs)[i++];
3456 ret = parse_probe_trace_command(node->s, tev);
3457 if (ret < 0)
3458 goto out;
3459 /* Set the uprobes attribute as same as original */
3460 tev->uprobes = pev->uprobes;
3461 }
3462 ret = i;
3463
3464 out:
3465 probe_cache__delete(cache);
3466 return ret;
3467 }
3468
convert_to_probe_trace_events(struct perf_probe_event * pev,struct probe_trace_event ** tevs)3469 static int convert_to_probe_trace_events(struct perf_probe_event *pev,
3470 struct probe_trace_event **tevs)
3471 {
3472 int ret;
3473
3474 if (!pev->group && !pev->sdt) {
3475 /* Set group name if not given */
3476 if (!pev->uprobes) {
3477 pev->group = strdup(PERFPROBE_GROUP);
3478 ret = pev->group ? 0 : -ENOMEM;
3479 } else
3480 ret = convert_exec_to_group(pev->target, &pev->group);
3481 if (ret != 0) {
3482 pr_warning("Failed to make a group name.\n");
3483 return ret;
3484 }
3485 }
3486
3487 ret = try_to_find_absolute_address(pev, tevs);
3488 if (ret > 0)
3489 return ret;
3490
3491 /* At first, we need to lookup cache entry */
3492 ret = find_probe_trace_events_from_cache(pev, tevs);
3493 if (ret > 0 || pev->sdt) /* SDT can be found only in the cache */
3494 return ret == 0 ? -ENOENT : ret; /* Found in probe cache */
3495
3496 /* Convert perf_probe_event with debuginfo */
3497 ret = try_to_find_probe_trace_events(pev, tevs);
3498 if (ret != 0)
3499 return ret; /* Found in debuginfo or got an error */
3500
3501 return find_probe_trace_events_from_map(pev, tevs);
3502 }
3503
convert_perf_probe_events(struct perf_probe_event * pevs,int npevs)3504 int convert_perf_probe_events(struct perf_probe_event *pevs, int npevs)
3505 {
3506 int i, ret;
3507
3508 /* Loop 1: convert all events */
3509 for (i = 0; i < npevs; i++) {
3510 /* Init kprobe blacklist if needed */
3511 if (!pevs[i].uprobes)
3512 kprobe_blacklist__init();
3513 /* Convert with or without debuginfo */
3514 ret = convert_to_probe_trace_events(&pevs[i], &pevs[i].tevs);
3515 if (ret < 0)
3516 return ret;
3517 pevs[i].ntevs = ret;
3518 }
3519 /* This just release blacklist only if allocated */
3520 kprobe_blacklist__release();
3521
3522 return 0;
3523 }
3524
show_probe_trace_event(struct probe_trace_event * tev)3525 static int show_probe_trace_event(struct probe_trace_event *tev)
3526 {
3527 char *buf = synthesize_probe_trace_command(tev);
3528
3529 if (!buf) {
3530 pr_debug("Failed to synthesize probe trace event.\n");
3531 return -EINVAL;
3532 }
3533
3534 /* Showing definition always go stdout */
3535 printf("%s\n", buf);
3536 free(buf);
3537
3538 return 0;
3539 }
3540
show_probe_trace_events(struct perf_probe_event * pevs,int npevs)3541 int show_probe_trace_events(struct perf_probe_event *pevs, int npevs)
3542 {
3543 struct strlist *namelist = strlist__new(NULL, NULL);
3544 struct probe_trace_event *tev;
3545 struct perf_probe_event *pev;
3546 int i, j, ret = 0;
3547
3548 if (!namelist)
3549 return -ENOMEM;
3550
3551 for (j = 0; j < npevs && !ret; j++) {
3552 pev = &pevs[j];
3553 for (i = 0; i < pev->ntevs && !ret; i++) {
3554 tev = &pev->tevs[i];
3555 /* Skip if the symbol is out of .text or blacklisted */
3556 if (!tev->point.symbol && !pev->uprobes)
3557 continue;
3558
3559 /* Set new name for tev (and update namelist) */
3560 ret = probe_trace_event__set_name(tev, pev,
3561 namelist, true);
3562 if (!ret)
3563 ret = show_probe_trace_event(tev);
3564 }
3565 }
3566 strlist__delete(namelist);
3567
3568 return ret;
3569 }
3570
show_bootconfig_event(struct probe_trace_event * tev)3571 static int show_bootconfig_event(struct probe_trace_event *tev)
3572 {
3573 struct probe_trace_point *tp = &tev->point;
3574 struct strbuf buf;
3575 char *ret = NULL;
3576 int err;
3577
3578 if (strbuf_init(&buf, 32) < 0)
3579 return -ENOMEM;
3580
3581 err = synthesize_kprobe_trace_def(tp, &buf);
3582 if (err >= 0)
3583 err = synthesize_probe_trace_args(tev, &buf);
3584 if (err >= 0)
3585 ret = strbuf_detach(&buf, NULL);
3586 strbuf_release(&buf);
3587
3588 if (ret) {
3589 printf("'%s'", ret);
3590 free(ret);
3591 }
3592
3593 return err;
3594 }
3595
show_bootconfig_events(struct perf_probe_event * pevs,int npevs)3596 int show_bootconfig_events(struct perf_probe_event *pevs, int npevs)
3597 {
3598 struct strlist *namelist = strlist__new(NULL, NULL);
3599 struct probe_trace_event *tev;
3600 struct perf_probe_event *pev;
3601 char *cur_name = NULL;
3602 int i, j, ret = 0;
3603
3604 if (!namelist)
3605 return -ENOMEM;
3606
3607 for (j = 0; j < npevs && !ret; j++) {
3608 pev = &pevs[j];
3609 if (pev->group && strcmp(pev->group, "probe"))
3610 pr_warning("WARN: Group name %s is ignored\n", pev->group);
3611 if (pev->uprobes) {
3612 pr_warning("ERROR: Bootconfig doesn't support uprobes\n");
3613 ret = -EINVAL;
3614 break;
3615 }
3616 for (i = 0; i < pev->ntevs && !ret; i++) {
3617 tev = &pev->tevs[i];
3618 /* Skip if the symbol is out of .text or blacklisted */
3619 if (!tev->point.symbol && !pev->uprobes)
3620 continue;
3621
3622 /* Set new name for tev (and update namelist) */
3623 ret = probe_trace_event__set_name(tev, pev,
3624 namelist, true);
3625 if (ret)
3626 break;
3627
3628 if (!cur_name || strcmp(cur_name, tev->event)) {
3629 printf("%sftrace.event.kprobes.%s.probe = ",
3630 cur_name ? "\n" : "", tev->event);
3631 cur_name = tev->event;
3632 } else
3633 printf(", ");
3634 ret = show_bootconfig_event(tev);
3635 }
3636 }
3637 printf("\n");
3638 strlist__delete(namelist);
3639
3640 return ret;
3641 }
3642
apply_perf_probe_events(struct perf_probe_event * pevs,int npevs)3643 int apply_perf_probe_events(struct perf_probe_event *pevs, int npevs)
3644 {
3645 int i, ret = 0;
3646
3647 /* Loop 2: add all events */
3648 for (i = 0; i < npevs; i++) {
3649 ret = __add_probe_trace_events(&pevs[i], pevs[i].tevs,
3650 pevs[i].ntevs,
3651 probe_conf.force_add);
3652 if (ret < 0)
3653 break;
3654 }
3655 return ret;
3656 }
3657
cleanup_perf_probe_events(struct perf_probe_event * pevs,int npevs)3658 void cleanup_perf_probe_events(struct perf_probe_event *pevs, int npevs)
3659 {
3660 int i, j;
3661 struct perf_probe_event *pev;
3662
3663 /* Loop 3: cleanup and free trace events */
3664 for (i = 0; i < npevs; i++) {
3665 pev = &pevs[i];
3666 for (j = 0; j < pevs[i].ntevs; j++)
3667 clear_probe_trace_event(&pevs[i].tevs[j]);
3668 zfree(&pevs[i].tevs);
3669 pevs[i].ntevs = 0;
3670 nsinfo__zput(pev->nsi);
3671 clear_perf_probe_event(&pevs[i]);
3672 }
3673 }
3674
add_perf_probe_events(struct perf_probe_event * pevs,int npevs)3675 int add_perf_probe_events(struct perf_probe_event *pevs, int npevs)
3676 {
3677 int ret;
3678
3679 ret = init_probe_symbol_maps(pevs->uprobes);
3680 if (ret < 0)
3681 return ret;
3682
3683 ret = convert_perf_probe_events(pevs, npevs);
3684 if (ret == 0)
3685 ret = apply_perf_probe_events(pevs, npevs);
3686
3687 cleanup_perf_probe_events(pevs, npevs);
3688
3689 exit_probe_symbol_maps();
3690 return ret;
3691 }
3692
del_perf_probe_events(struct strfilter * filter)3693 int del_perf_probe_events(struct strfilter *filter)
3694 {
3695 int ret, ret2, ufd = -1, kfd = -1;
3696 char *str = strfilter__string(filter);
3697
3698 if (!str)
3699 return -EINVAL;
3700
3701 /* Get current event names */
3702 ret = probe_file__open_both(&kfd, &ufd, PF_FL_RW);
3703 if (ret < 0)
3704 goto out;
3705
3706 ret = probe_file__del_events(kfd, filter);
3707 if (ret < 0 && ret != -ENOENT)
3708 goto error;
3709
3710 ret2 = probe_file__del_events(ufd, filter);
3711 if (ret2 < 0 && ret2 != -ENOENT) {
3712 ret = ret2;
3713 goto error;
3714 }
3715 ret = 0;
3716
3717 error:
3718 if (kfd >= 0)
3719 close(kfd);
3720 if (ufd >= 0)
3721 close(ufd);
3722 out:
3723 free(str);
3724
3725 return ret;
3726 }
3727
show_available_funcs(const char * target,struct nsinfo * nsi,struct strfilter * _filter,bool user)3728 int show_available_funcs(const char *target, struct nsinfo *nsi,
3729 struct strfilter *_filter, bool user)
3730 {
3731 struct rb_node *nd;
3732 struct map *map;
3733 int ret;
3734
3735 ret = init_probe_symbol_maps(user);
3736 if (ret < 0)
3737 return ret;
3738
3739 /* Get a symbol map */
3740 map = get_target_map(target, nsi, user);
3741 if (!map) {
3742 pr_err("Failed to get a map for %s\n", (target) ? : "kernel");
3743 return -EINVAL;
3744 }
3745
3746 ret = map__load(map);
3747 if (ret) {
3748 if (ret == -2) {
3749 char *str = strfilter__string(_filter);
3750 pr_err("Failed to find symbols matched to \"%s\"\n",
3751 str);
3752 free(str);
3753 } else
3754 pr_err("Failed to load symbols in %s\n",
3755 (target) ? : "kernel");
3756 goto end;
3757 }
3758 if (!dso__sorted_by_name(map->dso))
3759 dso__sort_by_name(map->dso);
3760
3761 /* Show all (filtered) symbols */
3762 setup_pager();
3763
3764 for (nd = rb_first_cached(&map->dso->symbol_names); nd;
3765 nd = rb_next(nd)) {
3766 struct symbol_name_rb_node *pos = rb_entry(nd, struct symbol_name_rb_node, rb_node);
3767
3768 if (strfilter__compare(_filter, pos->sym.name))
3769 printf("%s\n", pos->sym.name);
3770 }
3771 end:
3772 map__put(map);
3773 exit_probe_symbol_maps();
3774
3775 return ret;
3776 }
3777
copy_to_probe_trace_arg(struct probe_trace_arg * tvar,struct perf_probe_arg * pvar)3778 int copy_to_probe_trace_arg(struct probe_trace_arg *tvar,
3779 struct perf_probe_arg *pvar)
3780 {
3781 tvar->value = strdup(pvar->var);
3782 if (tvar->value == NULL)
3783 return -ENOMEM;
3784 if (pvar->type) {
3785 tvar->type = strdup(pvar->type);
3786 if (tvar->type == NULL)
3787 return -ENOMEM;
3788 }
3789 if (pvar->name) {
3790 tvar->name = strdup(pvar->name);
3791 if (tvar->name == NULL)
3792 return -ENOMEM;
3793 } else
3794 tvar->name = NULL;
3795 return 0;
3796 }
3797