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 "mutex.h"
33 #include "symbol.h"
34 #include <api/fs/fs.h>
35 #include "trace-event.h" /* For __maybe_unused */
36 #include "probe-event.h"
37 #include "probe-finder.h"
38 #include "probe-file.h"
39 #include "session.h"
40 #include "string2.h"
41 #include "strbuf.h"
42
43 #include <subcmd/pager.h>
44 #include <linux/ctype.h>
45 #include <linux/zalloc.h>
46
47 #ifdef HAVE_DEBUGINFOD_SUPPORT
48 #include <elfutils/debuginfod.h>
49 #endif
50
51 #define PERFPROBE_GROUP "probe"
52
53 bool probe_event_dry_run; /* Dry run flag */
54 struct probe_conf probe_conf = { .magic_num = DEFAULT_PROBE_MAGIC_NUM };
55
56 static char *synthesize_perf_probe_point(struct perf_probe_point *pp);
57
58 #define semantic_error(msg ...) pr_err("Semantic error :" msg)
59
e_snprintf(char * str,size_t size,const char * format,...)60 int e_snprintf(char *str, size_t size, const char *format, ...)
61 {
62 int ret;
63 va_list ap;
64 va_start(ap, format);
65 ret = vsnprintf(str, size, format, ap);
66 va_end(ap);
67 if (ret >= (int)size)
68 ret = -E2BIG;
69 return ret;
70 }
71
72 static struct machine *host_machine;
73
74 /* Initialize symbol maps and path of vmlinux/modules */
init_probe_symbol_maps(bool user_only)75 int init_probe_symbol_maps(bool user_only)
76 {
77 int ret;
78
79 symbol_conf.allow_aliases = true;
80 ret = symbol__init(NULL);
81 if (ret < 0) {
82 pr_debug("Failed to init symbol map.\n");
83 goto out;
84 }
85
86 if (host_machine || user_only) /* already initialized */
87 return 0;
88
89 if (symbol_conf.vmlinux_name)
90 pr_debug("Use vmlinux: %s\n", symbol_conf.vmlinux_name);
91
92 host_machine = machine__new_host();
93 if (!host_machine) {
94 pr_debug("machine__new_host() failed.\n");
95 symbol__exit();
96 ret = -1;
97 }
98 out:
99 if (ret < 0)
100 pr_warning("Failed to init vmlinux path.\n");
101 return ret;
102 }
103
exit_probe_symbol_maps(void)104 void exit_probe_symbol_maps(void)
105 {
106 machine__delete(host_machine);
107 host_machine = NULL;
108 symbol__exit();
109 }
110
kernel_get_ref_reloc_sym(struct map ** pmap)111 static struct ref_reloc_sym *kernel_get_ref_reloc_sym(struct map **pmap)
112 {
113 struct kmap *kmap;
114 struct map *map = machine__kernel_map(host_machine);
115
116 if (map__load(map) < 0)
117 return NULL;
118
119 kmap = map__kmap(map);
120 if (!kmap)
121 return NULL;
122
123 if (pmap)
124 *pmap = map;
125
126 return kmap->ref_reloc_sym;
127 }
128
kernel_get_symbol_address_by_name(const char * name,u64 * addr,bool reloc,bool reladdr)129 static int kernel_get_symbol_address_by_name(const char *name, u64 *addr,
130 bool reloc, bool reladdr)
131 {
132 struct ref_reloc_sym *reloc_sym;
133 struct symbol *sym;
134 struct map *map;
135
136 /* ref_reloc_sym is just a label. Need a special fix*/
137 reloc_sym = kernel_get_ref_reloc_sym(&map);
138 if (reloc_sym && strcmp(name, reloc_sym->name) == 0)
139 *addr = (!map__reloc(map) || reloc) ? reloc_sym->addr :
140 reloc_sym->unrelocated_addr;
141 else {
142 sym = machine__find_kernel_symbol_by_name(host_machine, name, &map);
143 if (!sym)
144 return -ENOENT;
145 *addr = map__unmap_ip(map, sym->start) -
146 ((reloc) ? 0 : map__reloc(map)) -
147 ((reladdr) ? map__start(map) : 0);
148 }
149 return 0;
150 }
151
152 struct kernel_get_module_map_cb_args {
153 const char *module;
154 struct map *result;
155 };
156
kernel_get_module_map_cb(struct map * map,void * data)157 static int kernel_get_module_map_cb(struct map *map, void *data)
158 {
159 struct kernel_get_module_map_cb_args *args = data;
160 struct dso *dso = map__dso(map);
161 const char *short_name = dso->short_name; /* short_name is "[module]" */
162 u16 short_name_len = dso->short_name_len;
163
164 if (strncmp(short_name + 1, args->module, short_name_len - 2) == 0 &&
165 args->module[short_name_len - 2] == '\0') {
166 args->result = map__get(map);
167 return 1;
168 }
169 return 0;
170 }
171
kernel_get_module_map(const char * module)172 static struct map *kernel_get_module_map(const char *module)
173 {
174 struct kernel_get_module_map_cb_args args = {
175 .module = module,
176 .result = NULL,
177 };
178
179 /* A file path -- this is an offline module */
180 if (module && strchr(module, '/'))
181 return dso__new_map(module);
182
183 if (!module) {
184 struct map *map = machine__kernel_map(host_machine);
185
186 return map__get(map);
187 }
188
189 maps__for_each_map(machine__kernel_maps(host_machine), kernel_get_module_map_cb, &args);
190
191 return args.result;
192 }
193
get_target_map(const char * target,struct nsinfo * nsi,bool user)194 struct map *get_target_map(const char *target, struct nsinfo *nsi, bool user)
195 {
196 /* Init maps of given executable or kernel */
197 if (user) {
198 struct map *map;
199 struct dso *dso;
200
201 map = dso__new_map(target);
202 dso = map ? map__dso(map) : NULL;
203 if (dso) {
204 mutex_lock(&dso->lock);
205 nsinfo__put(dso->nsinfo);
206 dso->nsinfo = nsinfo__get(nsi);
207 mutex_unlock(&dso->lock);
208 }
209 return map;
210 } else {
211 return kernel_get_module_map(target);
212 }
213 }
214
convert_exec_to_group(const char * exec,char ** result)215 static int convert_exec_to_group(const char *exec, char **result)
216 {
217 char *ptr1, *ptr2, *exec_copy;
218 char buf[64];
219 int ret;
220
221 exec_copy = strdup(exec);
222 if (!exec_copy)
223 return -ENOMEM;
224
225 ptr1 = basename(exec_copy);
226 if (!ptr1) {
227 ret = -EINVAL;
228 goto out;
229 }
230
231 for (ptr2 = ptr1; *ptr2 != '\0'; ptr2++) {
232 if (!isalnum(*ptr2) && *ptr2 != '_') {
233 *ptr2 = '\0';
234 break;
235 }
236 }
237
238 ret = e_snprintf(buf, 64, "%s_%s", PERFPROBE_GROUP, ptr1);
239 if (ret < 0)
240 goto out;
241
242 *result = strdup(buf);
243 ret = *result ? 0 : -ENOMEM;
244
245 out:
246 free(exec_copy);
247 return ret;
248 }
249
clear_perf_probe_point(struct perf_probe_point * pp)250 static void clear_perf_probe_point(struct perf_probe_point *pp)
251 {
252 zfree(&pp->file);
253 zfree(&pp->function);
254 zfree(&pp->lazy_line);
255 }
256
clear_probe_trace_events(struct probe_trace_event * tevs,int ntevs)257 static void clear_probe_trace_events(struct probe_trace_event *tevs, int ntevs)
258 {
259 int i;
260
261 for (i = 0; i < ntevs; i++)
262 clear_probe_trace_event(tevs + i);
263 }
264
265 static bool kprobe_blacklist__listed(u64 address);
kprobe_warn_out_range(const char * symbol,u64 address)266 static bool kprobe_warn_out_range(const char *symbol, u64 address)
267 {
268 struct map *map;
269 bool ret = false;
270
271 map = kernel_get_module_map(NULL);
272 if (map) {
273 ret = address <= map__start(map) || map__end(map) < address;
274 if (ret)
275 pr_warning("%s is out of .text, skip it.\n", symbol);
276 map__put(map);
277 }
278 if (!ret && kprobe_blacklist__listed(address)) {
279 pr_warning("%s is blacklisted function, skip it.\n", symbol);
280 ret = true;
281 }
282
283 return ret;
284 }
285
286 /*
287 * @module can be module name of module file path. In case of path,
288 * inspect elf and find out what is actual module name.
289 * Caller has to free mod_name after using it.
290 */
find_module_name(const char * module)291 static char *find_module_name(const char *module)
292 {
293 int fd;
294 Elf *elf;
295 GElf_Ehdr ehdr;
296 GElf_Shdr shdr;
297 Elf_Data *data;
298 Elf_Scn *sec;
299 char *mod_name = NULL;
300 int name_offset;
301
302 fd = open(module, O_RDONLY);
303 if (fd < 0)
304 return NULL;
305
306 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
307 if (elf == NULL)
308 goto elf_err;
309
310 if (gelf_getehdr(elf, &ehdr) == NULL)
311 goto ret_err;
312
313 sec = elf_section_by_name(elf, &ehdr, &shdr,
314 ".gnu.linkonce.this_module", NULL);
315 if (!sec)
316 goto ret_err;
317
318 data = elf_getdata(sec, NULL);
319 if (!data || !data->d_buf)
320 goto ret_err;
321
322 /*
323 * NOTE:
324 * '.gnu.linkonce.this_module' section of kernel module elf directly
325 * maps to 'struct module' from linux/module.h. This section contains
326 * actual module name which will be used by kernel after loading it.
327 * But, we cannot use 'struct module' here since linux/module.h is not
328 * exposed to user-space. Offset of 'name' has remained same from long
329 * time, so hardcoding it here.
330 */
331 if (ehdr.e_ident[EI_CLASS] == ELFCLASS32)
332 name_offset = 12;
333 else /* expect ELFCLASS64 by default */
334 name_offset = 24;
335
336 mod_name = strdup((char *)data->d_buf + name_offset);
337
338 ret_err:
339 elf_end(elf);
340 elf_err:
341 close(fd);
342 return mod_name;
343 }
344
345 #ifdef HAVE_DWARF_SUPPORT
346
kernel_get_module_dso(const char * module,struct dso ** pdso)347 static int kernel_get_module_dso(const char *module, struct dso **pdso)
348 {
349 struct dso *dso;
350 struct map *map;
351 const char *vmlinux_name;
352 int ret = 0;
353
354 if (module) {
355 char module_name[128];
356
357 snprintf(module_name, sizeof(module_name), "[%s]", module);
358 map = maps__find_by_name(machine__kernel_maps(host_machine), module_name);
359 if (map) {
360 dso = map__dso(map);
361 goto found;
362 }
363 pr_debug("Failed to find module %s.\n", module);
364 return -ENOENT;
365 }
366
367 map = machine__kernel_map(host_machine);
368 dso = map__dso(map);
369 if (!dso->has_build_id)
370 dso__read_running_kernel_build_id(dso, host_machine);
371
372 vmlinux_name = symbol_conf.vmlinux_name;
373 dso->load_errno = 0;
374 if (vmlinux_name)
375 ret = dso__load_vmlinux(dso, map, vmlinux_name, false);
376 else
377 ret = dso__load_vmlinux_path(dso, map);
378 found:
379 *pdso = dso;
380 return ret;
381 }
382
383 /*
384 * Some binaries like glibc have special symbols which are on the symbol
385 * table, but not in the debuginfo. If we can find the address of the
386 * symbol from map, we can translate the address back to the probe point.
387 */
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)388 static int find_alternative_probe_point(struct debuginfo *dinfo,
389 struct perf_probe_point *pp,
390 struct perf_probe_point *result,
391 const char *target, struct nsinfo *nsi,
392 bool uprobes)
393 {
394 struct map *map = NULL;
395 struct symbol *sym;
396 u64 address = 0;
397 int ret = -ENOENT;
398 size_t idx;
399
400 /* This can work only for function-name based one */
401 if (!pp->function || pp->file)
402 return -ENOTSUP;
403
404 map = get_target_map(target, nsi, uprobes);
405 if (!map)
406 return -EINVAL;
407
408 /* Find the address of given function */
409 map__for_each_symbol_by_name(map, pp->function, sym, idx) {
410 if (uprobes) {
411 address = sym->start;
412 if (sym->type == STT_GNU_IFUNC)
413 pr_warning("Warning: The probe function (%s) is a GNU indirect function.\n"
414 "Consider identifying the final function used at run time and set the probe directly on that.\n",
415 pp->function);
416 } else
417 address = map__unmap_ip(map, sym->start) - map__reloc(map);
418 break;
419 }
420 if (!address) {
421 ret = -ENOENT;
422 goto out;
423 }
424 pr_debug("Symbol %s address found : %" PRIx64 "\n",
425 pp->function, address);
426
427 ret = debuginfo__find_probe_point(dinfo, address, result);
428 if (ret <= 0)
429 ret = (!ret) ? -ENOENT : ret;
430 else {
431 result->offset += pp->offset;
432 result->line += pp->line;
433 result->retprobe = pp->retprobe;
434 ret = 0;
435 }
436
437 out:
438 map__put(map);
439 return ret;
440
441 }
442
get_alternative_probe_event(struct debuginfo * dinfo,struct perf_probe_event * pev,struct perf_probe_point * tmp)443 static int get_alternative_probe_event(struct debuginfo *dinfo,
444 struct perf_probe_event *pev,
445 struct perf_probe_point *tmp)
446 {
447 int ret;
448
449 memcpy(tmp, &pev->point, sizeof(*tmp));
450 memset(&pev->point, 0, sizeof(pev->point));
451 ret = find_alternative_probe_point(dinfo, tmp, &pev->point, pev->target,
452 pev->nsi, pev->uprobes);
453 if (ret < 0)
454 memcpy(&pev->point, tmp, sizeof(*tmp));
455
456 return ret;
457 }
458
get_alternative_line_range(struct debuginfo * dinfo,struct line_range * lr,const char * target,bool user)459 static int get_alternative_line_range(struct debuginfo *dinfo,
460 struct line_range *lr,
461 const char *target, bool user)
462 {
463 struct perf_probe_point pp = { .function = lr->function,
464 .file = lr->file,
465 .line = lr->start };
466 struct perf_probe_point result;
467 int ret, len = 0;
468
469 memset(&result, 0, sizeof(result));
470
471 if (lr->end != INT_MAX)
472 len = lr->end - lr->start;
473 ret = find_alternative_probe_point(dinfo, &pp, &result,
474 target, NULL, user);
475 if (!ret) {
476 lr->function = result.function;
477 lr->file = result.file;
478 lr->start = result.line;
479 if (lr->end != INT_MAX)
480 lr->end = lr->start + len;
481 clear_perf_probe_point(&pp);
482 }
483 return ret;
484 }
485
486 #ifdef HAVE_DEBUGINFOD_SUPPORT
open_from_debuginfod(struct dso * dso,struct nsinfo * nsi,bool silent)487 static struct debuginfo *open_from_debuginfod(struct dso *dso, struct nsinfo *nsi,
488 bool silent)
489 {
490 debuginfod_client *c = debuginfod_begin();
491 char sbuild_id[SBUILD_ID_SIZE + 1];
492 struct debuginfo *ret = NULL;
493 struct nscookie nsc;
494 char *path;
495 int fd;
496
497 if (!c)
498 return NULL;
499
500 build_id__sprintf(&dso->bid, sbuild_id);
501 fd = debuginfod_find_debuginfo(c, (const unsigned char *)sbuild_id,
502 0, &path);
503 if (fd >= 0)
504 close(fd);
505 debuginfod_end(c);
506 if (fd < 0) {
507 if (!silent)
508 pr_debug("Failed to find debuginfo in debuginfod.\n");
509 return NULL;
510 }
511 if (!silent)
512 pr_debug("Load debuginfo from debuginfod (%s)\n", path);
513
514 nsinfo__mountns_enter(nsi, &nsc);
515 ret = debuginfo__new((const char *)path);
516 nsinfo__mountns_exit(&nsc);
517 return ret;
518 }
519 #else
520 static inline
open_from_debuginfod(struct dso * dso __maybe_unused,struct nsinfo * nsi __maybe_unused,bool silent __maybe_unused)521 struct debuginfo *open_from_debuginfod(struct dso *dso __maybe_unused,
522 struct nsinfo *nsi __maybe_unused,
523 bool silent __maybe_unused)
524 {
525 return NULL;
526 }
527 #endif
528
529 /* Open new debuginfo of given module */
open_debuginfo(const char * module,struct nsinfo * nsi,bool silent)530 static struct debuginfo *open_debuginfo(const char *module, struct nsinfo *nsi,
531 bool silent)
532 {
533 const char *path = module;
534 char reason[STRERR_BUFSIZE];
535 struct debuginfo *ret = NULL;
536 struct dso *dso = NULL;
537 struct nscookie nsc;
538 int err;
539
540 if (!module || !strchr(module, '/')) {
541 err = kernel_get_module_dso(module, &dso);
542 if (err < 0) {
543 if (!dso || dso->load_errno == 0) {
544 if (!str_error_r(-err, reason, STRERR_BUFSIZE))
545 strcpy(reason, "(unknown)");
546 } else
547 dso__strerror_load(dso, reason, STRERR_BUFSIZE);
548 if (dso)
549 ret = open_from_debuginfod(dso, nsi, silent);
550 if (ret)
551 return ret;
552 if (!silent) {
553 if (module)
554 pr_err("Module %s is not loaded, please specify its full path name.\n", module);
555 else
556 pr_err("Failed to find the path for the kernel: %s\n", reason);
557 }
558 return NULL;
559 }
560 path = dso->long_name;
561 }
562 nsinfo__mountns_enter(nsi, &nsc);
563 ret = debuginfo__new(path);
564 if (!ret && !silent) {
565 pr_warning("The %s file has no debug information.\n", path);
566 if (!module || !strtailcmp(path, ".ko"))
567 pr_warning("Rebuild with CONFIG_DEBUG_INFO=y, ");
568 else
569 pr_warning("Rebuild with -g, ");
570 pr_warning("or install an appropriate debuginfo package.\n");
571 }
572 nsinfo__mountns_exit(&nsc);
573 return ret;
574 }
575
576 /* For caching the last debuginfo */
577 static struct debuginfo *debuginfo_cache;
578 static char *debuginfo_cache_path;
579
debuginfo_cache__open(const char * module,bool silent)580 static struct debuginfo *debuginfo_cache__open(const char *module, bool silent)
581 {
582 const char *path = module;
583
584 /* If the module is NULL, it should be the kernel. */
585 if (!module)
586 path = "kernel";
587
588 if (debuginfo_cache_path && !strcmp(debuginfo_cache_path, path))
589 goto out;
590
591 /* Copy module path */
592 free(debuginfo_cache_path);
593 debuginfo_cache_path = strdup(path);
594 if (!debuginfo_cache_path) {
595 debuginfo__delete(debuginfo_cache);
596 debuginfo_cache = NULL;
597 goto out;
598 }
599
600 debuginfo_cache = open_debuginfo(module, NULL, silent);
601 if (!debuginfo_cache)
602 zfree(&debuginfo_cache_path);
603 out:
604 return debuginfo_cache;
605 }
606
debuginfo_cache__exit(void)607 static void debuginfo_cache__exit(void)
608 {
609 debuginfo__delete(debuginfo_cache);
610 debuginfo_cache = NULL;
611 zfree(&debuginfo_cache_path);
612 }
613
614
get_text_start_address(const char * exec,u64 * address,struct nsinfo * nsi)615 static int get_text_start_address(const char *exec, u64 *address,
616 struct nsinfo *nsi)
617 {
618 Elf *elf;
619 GElf_Ehdr ehdr;
620 GElf_Shdr shdr;
621 int fd, ret = -ENOENT;
622 struct nscookie nsc;
623
624 nsinfo__mountns_enter(nsi, &nsc);
625 fd = open(exec, O_RDONLY);
626 nsinfo__mountns_exit(&nsc);
627 if (fd < 0)
628 return -errno;
629
630 elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
631 if (elf == NULL) {
632 ret = -EINVAL;
633 goto out_close;
634 }
635
636 if (gelf_getehdr(elf, &ehdr) == NULL)
637 goto out;
638
639 if (!elf_section_by_name(elf, &ehdr, &shdr, ".text", NULL))
640 goto out;
641
642 *address = shdr.sh_addr - shdr.sh_offset;
643 ret = 0;
644 out:
645 elf_end(elf);
646 out_close:
647 close(fd);
648
649 return ret;
650 }
651
652 /*
653 * Convert trace point to probe point with debuginfo
654 */
find_perf_probe_point_from_dwarf(struct probe_trace_point * tp,struct perf_probe_point * pp,bool is_kprobe)655 static int find_perf_probe_point_from_dwarf(struct probe_trace_point *tp,
656 struct perf_probe_point *pp,
657 bool is_kprobe)
658 {
659 struct debuginfo *dinfo = NULL;
660 u64 stext = 0;
661 u64 addr = tp->address;
662 int ret = -ENOENT;
663
664 /* convert the address to dwarf address */
665 if (!is_kprobe) {
666 if (!addr) {
667 ret = -EINVAL;
668 goto error;
669 }
670 ret = get_text_start_address(tp->module, &stext, NULL);
671 if (ret < 0)
672 goto error;
673 addr += stext;
674 } else if (tp->symbol) {
675 /* If the module is given, this returns relative address */
676 ret = kernel_get_symbol_address_by_name(tp->symbol, &addr,
677 false, !!tp->module);
678 if (ret != 0)
679 goto error;
680 addr += tp->offset;
681 }
682
683 pr_debug("try to find information at %" PRIx64 " in %s\n", addr,
684 tp->module ? : "kernel");
685
686 dinfo = debuginfo_cache__open(tp->module, verbose <= 0);
687 if (dinfo)
688 ret = debuginfo__find_probe_point(dinfo, addr, pp);
689 else
690 ret = -ENOENT;
691
692 if (ret > 0) {
693 pp->retprobe = tp->retprobe;
694 return 0;
695 }
696 error:
697 pr_debug("Failed to find corresponding probes from debuginfo.\n");
698 return ret ? : -ENOENT;
699 }
700
701 /* Adjust symbol name and address */
post_process_probe_trace_point(struct probe_trace_point * tp,struct map * map,u64 offs)702 static int post_process_probe_trace_point(struct probe_trace_point *tp,
703 struct map *map, u64 offs)
704 {
705 struct symbol *sym;
706 u64 addr = tp->address - offs;
707
708 sym = map__find_symbol(map, addr);
709 if (!sym) {
710 /*
711 * If the address is in the inittext section, map can not
712 * find it. Ignore it if we are probing offline kernel.
713 */
714 return (symbol_conf.ignore_vmlinux_buildid) ? 0 : -ENOENT;
715 }
716
717 if (strcmp(sym->name, tp->symbol)) {
718 /* If we have no realname, use symbol for it */
719 if (!tp->realname)
720 tp->realname = tp->symbol;
721 else
722 free(tp->symbol);
723 tp->symbol = strdup(sym->name);
724 if (!tp->symbol)
725 return -ENOMEM;
726 }
727 tp->offset = addr - sym->start;
728 tp->address -= offs;
729
730 return 0;
731 }
732
733 /*
734 * Rename DWARF symbols to ELF symbols -- gcc sometimes optimizes functions
735 * and generate new symbols with suffixes such as .constprop.N or .isra.N
736 * etc. Since those symbols are not recorded in DWARF, we have to find
737 * correct generated symbols from offline ELF binary.
738 * For online kernel or uprobes we don't need this because those are
739 * rebased on _text, or already a section relative address.
740 */
741 static int
post_process_offline_probe_trace_events(struct probe_trace_event * tevs,int ntevs,const char * pathname)742 post_process_offline_probe_trace_events(struct probe_trace_event *tevs,
743 int ntevs, const char *pathname)
744 {
745 struct map *map;
746 u64 stext = 0;
747 int i, ret = 0;
748
749 /* Prepare a map for offline binary */
750 map = dso__new_map(pathname);
751 if (!map || get_text_start_address(pathname, &stext, NULL) < 0) {
752 pr_warning("Failed to get ELF symbols for %s\n", pathname);
753 return -EINVAL;
754 }
755
756 for (i = 0; i < ntevs; i++) {
757 ret = post_process_probe_trace_point(&tevs[i].point,
758 map, stext);
759 if (ret < 0)
760 break;
761 }
762 map__put(map);
763
764 return ret;
765 }
766
add_exec_to_probe_trace_events(struct probe_trace_event * tevs,int ntevs,const char * exec,struct nsinfo * nsi)767 static int add_exec_to_probe_trace_events(struct probe_trace_event *tevs,
768 int ntevs, const char *exec,
769 struct nsinfo *nsi)
770 {
771 int i, ret = 0;
772 u64 stext = 0;
773
774 if (!exec)
775 return 0;
776
777 ret = get_text_start_address(exec, &stext, nsi);
778 if (ret < 0)
779 return ret;
780
781 for (i = 0; i < ntevs && ret >= 0; i++) {
782 /* point.address is the address of point.symbol + point.offset */
783 tevs[i].point.address -= stext;
784 tevs[i].point.module = strdup(exec);
785 if (!tevs[i].point.module) {
786 ret = -ENOMEM;
787 break;
788 }
789 tevs[i].uprobes = true;
790 }
791
792 return ret;
793 }
794
795 static int
post_process_module_probe_trace_events(struct probe_trace_event * tevs,int ntevs,const char * module,struct debuginfo * dinfo)796 post_process_module_probe_trace_events(struct probe_trace_event *tevs,
797 int ntevs, const char *module,
798 struct debuginfo *dinfo)
799 {
800 Dwarf_Addr text_offs = 0;
801 int i, ret = 0;
802 char *mod_name = NULL;
803 struct map *map;
804
805 if (!module)
806 return 0;
807
808 map = get_target_map(module, NULL, false);
809 if (!map || debuginfo__get_text_offset(dinfo, &text_offs, true) < 0) {
810 pr_warning("Failed to get ELF symbols for %s\n", module);
811 return -EINVAL;
812 }
813
814 mod_name = find_module_name(module);
815 for (i = 0; i < ntevs; i++) {
816 ret = post_process_probe_trace_point(&tevs[i].point,
817 map, text_offs);
818 if (ret < 0)
819 break;
820 tevs[i].point.module =
821 strdup(mod_name ? mod_name : module);
822 if (!tevs[i].point.module) {
823 ret = -ENOMEM;
824 break;
825 }
826 }
827
828 free(mod_name);
829 map__put(map);
830
831 return ret;
832 }
833
834 static int
post_process_kernel_probe_trace_events(struct probe_trace_event * tevs,int ntevs)835 post_process_kernel_probe_trace_events(struct probe_trace_event *tevs,
836 int ntevs)
837 {
838 struct ref_reloc_sym *reloc_sym;
839 struct map *map;
840 char *tmp;
841 int i, skipped = 0;
842
843 /* Skip post process if the target is an offline kernel */
844 if (symbol_conf.ignore_vmlinux_buildid)
845 return post_process_offline_probe_trace_events(tevs, ntevs,
846 symbol_conf.vmlinux_name);
847
848 reloc_sym = kernel_get_ref_reloc_sym(&map);
849 if (!reloc_sym) {
850 pr_warning("Relocated base symbol is not found! "
851 "Check /proc/sys/kernel/kptr_restrict\n"
852 "and /proc/sys/kernel/perf_event_paranoid. "
853 "Or run as privileged perf user.\n\n");
854 return -EINVAL;
855 }
856
857 for (i = 0; i < ntevs; i++) {
858 if (!tevs[i].point.address)
859 continue;
860 if (tevs[i].point.retprobe && !kretprobe_offset_is_supported())
861 continue;
862 /*
863 * If we found a wrong one, mark it by NULL symbol.
864 * Since addresses in debuginfo is same as objdump, we need
865 * to convert it to addresses on memory.
866 */
867 if (kprobe_warn_out_range(tevs[i].point.symbol,
868 map__objdump_2mem(map, tevs[i].point.address))) {
869 tmp = NULL;
870 skipped++;
871 } else {
872 tmp = strdup(reloc_sym->name);
873 if (!tmp)
874 return -ENOMEM;
875 }
876 /* If we have no realname, use symbol for it */
877 if (!tevs[i].point.realname)
878 tevs[i].point.realname = tevs[i].point.symbol;
879 else
880 free(tevs[i].point.symbol);
881 tevs[i].point.symbol = tmp;
882 tevs[i].point.offset = tevs[i].point.address -
883 (map__reloc(map) ? reloc_sym->unrelocated_addr :
884 reloc_sym->addr);
885 }
886 return skipped;
887 }
888
889 void __weak
arch__post_process_probe_trace_events(struct perf_probe_event * pev __maybe_unused,int ntevs __maybe_unused)890 arch__post_process_probe_trace_events(struct perf_probe_event *pev __maybe_unused,
891 int ntevs __maybe_unused)
892 {
893 }
894
895 /* 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)896 static int post_process_probe_trace_events(struct perf_probe_event *pev,
897 struct probe_trace_event *tevs,
898 int ntevs, const char *module,
899 bool uprobe, struct debuginfo *dinfo)
900 {
901 int ret;
902
903 if (uprobe)
904 ret = add_exec_to_probe_trace_events(tevs, ntevs, module,
905 pev->nsi);
906 else if (module)
907 /* Currently ref_reloc_sym based probe is not for drivers */
908 ret = post_process_module_probe_trace_events(tevs, ntevs,
909 module, dinfo);
910 else
911 ret = post_process_kernel_probe_trace_events(tevs, ntevs);
912
913 if (ret >= 0)
914 arch__post_process_probe_trace_events(pev, ntevs);
915
916 return ret;
917 }
918
919 /* Try to find perf_probe_event with debuginfo */
try_to_find_probe_trace_events(struct perf_probe_event * pev,struct probe_trace_event ** tevs)920 static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
921 struct probe_trace_event **tevs)
922 {
923 bool need_dwarf = perf_probe_event_need_dwarf(pev);
924 struct perf_probe_point tmp;
925 struct debuginfo *dinfo;
926 int ntevs, ret = 0;
927
928 /* Workaround for gcc #98776 issue.
929 * Perf failed to add kretprobe event with debuginfo of vmlinux which is
930 * compiled by gcc with -fpatchable-function-entry option enabled. The
931 * same issue with kernel module. The retprobe doesn`t need debuginfo.
932 * This workaround solution use map to query the probe function address
933 * for retprobe event.
934 */
935 if (pev->point.retprobe)
936 return 0;
937
938 dinfo = open_debuginfo(pev->target, pev->nsi, !need_dwarf);
939 if (!dinfo) {
940 if (need_dwarf)
941 return -ENODATA;
942 pr_debug("Could not open debuginfo. Try to use symbols.\n");
943 return 0;
944 }
945
946 pr_debug("Try to find probe point from debuginfo.\n");
947 /* Searching trace events corresponding to a probe event */
948 ntevs = debuginfo__find_trace_events(dinfo, pev, tevs);
949
950 if (ntevs == 0) { /* Not found, retry with an alternative */
951 ret = get_alternative_probe_event(dinfo, pev, &tmp);
952 if (!ret) {
953 ntevs = debuginfo__find_trace_events(dinfo, pev, tevs);
954 /*
955 * Write back to the original probe_event for
956 * setting appropriate (user given) event name
957 */
958 clear_perf_probe_point(&pev->point);
959 memcpy(&pev->point, &tmp, sizeof(tmp));
960 }
961 }
962
963 if (ntevs > 0) { /* Succeeded to find trace events */
964 pr_debug("Found %d probe_trace_events.\n", ntevs);
965 ret = post_process_probe_trace_events(pev, *tevs, ntevs,
966 pev->target, pev->uprobes, dinfo);
967 if (ret < 0 || ret == ntevs) {
968 pr_debug("Post processing failed or all events are skipped. (%d)\n", ret);
969 clear_probe_trace_events(*tevs, ntevs);
970 zfree(tevs);
971 ntevs = 0;
972 }
973 }
974
975 debuginfo__delete(dinfo);
976
977 if (ntevs == 0) { /* No error but failed to find probe point. */
978 char *probe_point = synthesize_perf_probe_point(&pev->point);
979 pr_warning("Probe point '%s' not found.\n", probe_point);
980 free(probe_point);
981 return -ENODEV;
982 } else if (ntevs < 0) {
983 /* Error path : ntevs < 0 */
984 pr_debug("An error occurred in debuginfo analysis (%d).\n", ntevs);
985 if (ntevs == -EBADF)
986 pr_warning("Warning: No dwarf info found in the vmlinux - "
987 "please rebuild kernel with CONFIG_DEBUG_INFO=y.\n");
988 if (!need_dwarf) {
989 pr_debug("Trying to use symbols.\n");
990 return 0;
991 }
992 }
993 return ntevs;
994 }
995
996 #define LINEBUF_SIZE 256
997 #define NR_ADDITIONAL_LINES 2
998
__show_one_line(FILE * fp,int l,bool skip,bool show_num)999 static int __show_one_line(FILE *fp, int l, bool skip, bool show_num)
1000 {
1001 char buf[LINEBUF_SIZE], sbuf[STRERR_BUFSIZE];
1002 const char *color = show_num ? "" : PERF_COLOR_BLUE;
1003 const char *prefix = NULL;
1004
1005 do {
1006 if (fgets(buf, LINEBUF_SIZE, fp) == NULL)
1007 goto error;
1008 if (skip)
1009 continue;
1010 if (!prefix) {
1011 prefix = show_num ? "%7d " : " ";
1012 color_fprintf(stdout, color, prefix, l);
1013 }
1014 color_fprintf(stdout, color, "%s", buf);
1015
1016 } while (strchr(buf, '\n') == NULL);
1017
1018 return 1;
1019 error:
1020 if (ferror(fp)) {
1021 pr_warning("File read error: %s\n",
1022 str_error_r(errno, sbuf, sizeof(sbuf)));
1023 return -1;
1024 }
1025 return 0;
1026 }
1027
_show_one_line(FILE * fp,int l,bool skip,bool show_num)1028 static int _show_one_line(FILE *fp, int l, bool skip, bool show_num)
1029 {
1030 int rv = __show_one_line(fp, l, skip, show_num);
1031 if (rv == 0) {
1032 pr_warning("Source file is shorter than expected.\n");
1033 rv = -1;
1034 }
1035 return rv;
1036 }
1037
1038 #define show_one_line_with_num(f,l) _show_one_line(f,l,false,true)
1039 #define show_one_line(f,l) _show_one_line(f,l,false,false)
1040 #define skip_one_line(f,l) _show_one_line(f,l,true,false)
1041 #define show_one_line_or_eof(f,l) __show_one_line(f,l,false,false)
1042
1043 /*
1044 * Show line-range always requires debuginfo to find source file and
1045 * line number.
1046 */
__show_line_range(struct line_range * lr,const char * module,bool user)1047 static int __show_line_range(struct line_range *lr, const char *module,
1048 bool user)
1049 {
1050 struct build_id bid;
1051 int l = 1;
1052 struct int_node *ln;
1053 struct debuginfo *dinfo;
1054 FILE *fp;
1055 int ret;
1056 char *tmp;
1057 char sbuf[STRERR_BUFSIZE];
1058 char sbuild_id[SBUILD_ID_SIZE] = "";
1059
1060 /* Search a line range */
1061 dinfo = open_debuginfo(module, NULL, false);
1062 if (!dinfo)
1063 return -ENOENT;
1064
1065 ret = debuginfo__find_line_range(dinfo, lr);
1066 if (!ret) { /* Not found, retry with an alternative */
1067 ret = get_alternative_line_range(dinfo, lr, module, user);
1068 if (!ret)
1069 ret = debuginfo__find_line_range(dinfo, lr);
1070 }
1071 if (dinfo->build_id) {
1072 build_id__init(&bid, dinfo->build_id, BUILD_ID_SIZE);
1073 build_id__sprintf(&bid, sbuild_id);
1074 }
1075 debuginfo__delete(dinfo);
1076 if (ret == 0 || ret == -ENOENT) {
1077 pr_warning("Specified source line is not found.\n");
1078 return -ENOENT;
1079 } else if (ret < 0) {
1080 pr_warning("Debuginfo analysis failed.\n");
1081 return ret;
1082 }
1083
1084 /* Convert source file path */
1085 tmp = lr->path;
1086 ret = find_source_path(tmp, sbuild_id, lr->comp_dir, &lr->path);
1087
1088 /* Free old path when new path is assigned */
1089 if (tmp != lr->path)
1090 free(tmp);
1091
1092 if (ret < 0) {
1093 pr_warning("Failed to find source file path.\n");
1094 return ret;
1095 }
1096
1097 setup_pager();
1098
1099 if (lr->function)
1100 fprintf(stdout, "<%s@%s:%d>\n", lr->function, lr->path,
1101 lr->start - lr->offset);
1102 else
1103 fprintf(stdout, "<%s:%d>\n", lr->path, lr->start);
1104
1105 fp = fopen(lr->path, "r");
1106 if (fp == NULL) {
1107 pr_warning("Failed to open %s: %s\n", lr->path,
1108 str_error_r(errno, sbuf, sizeof(sbuf)));
1109 return -errno;
1110 }
1111 /* Skip to starting line number */
1112 while (l < lr->start) {
1113 ret = skip_one_line(fp, l++);
1114 if (ret < 0)
1115 goto end;
1116 }
1117
1118 intlist__for_each_entry(ln, lr->line_list) {
1119 for (; ln->i > (unsigned long)l; l++) {
1120 ret = show_one_line(fp, l - lr->offset);
1121 if (ret < 0)
1122 goto end;
1123 }
1124 ret = show_one_line_with_num(fp, l++ - lr->offset);
1125 if (ret < 0)
1126 goto end;
1127 }
1128
1129 if (lr->end == INT_MAX)
1130 lr->end = l + NR_ADDITIONAL_LINES;
1131 while (l <= lr->end) {
1132 ret = show_one_line_or_eof(fp, l++ - lr->offset);
1133 if (ret <= 0)
1134 break;
1135 }
1136 end:
1137 fclose(fp);
1138 return ret;
1139 }
1140
show_line_range(struct line_range * lr,const char * module,struct nsinfo * nsi,bool user)1141 int show_line_range(struct line_range *lr, const char *module,
1142 struct nsinfo *nsi, bool user)
1143 {
1144 int ret;
1145 struct nscookie nsc;
1146
1147 ret = init_probe_symbol_maps(user);
1148 if (ret < 0)
1149 return ret;
1150 nsinfo__mountns_enter(nsi, &nsc);
1151 ret = __show_line_range(lr, module, user);
1152 nsinfo__mountns_exit(&nsc);
1153 exit_probe_symbol_maps();
1154
1155 return ret;
1156 }
1157
show_available_vars_at(struct debuginfo * dinfo,struct perf_probe_event * pev,struct strfilter * _filter)1158 static int show_available_vars_at(struct debuginfo *dinfo,
1159 struct perf_probe_event *pev,
1160 struct strfilter *_filter)
1161 {
1162 char *buf;
1163 int ret, i, nvars;
1164 struct str_node *node;
1165 struct variable_list *vls = NULL, *vl;
1166 struct perf_probe_point tmp;
1167 const char *var;
1168
1169 buf = synthesize_perf_probe_point(&pev->point);
1170 if (!buf)
1171 return -EINVAL;
1172 pr_debug("Searching variables at %s\n", buf);
1173
1174 ret = debuginfo__find_available_vars_at(dinfo, pev, &vls);
1175 if (!ret) { /* Not found, retry with an alternative */
1176 ret = get_alternative_probe_event(dinfo, pev, &tmp);
1177 if (!ret) {
1178 ret = debuginfo__find_available_vars_at(dinfo, pev,
1179 &vls);
1180 /* Release the old probe_point */
1181 clear_perf_probe_point(&tmp);
1182 }
1183 }
1184 if (ret <= 0) {
1185 if (ret == 0 || ret == -ENOENT) {
1186 pr_err("Failed to find the address of %s\n", buf);
1187 ret = -ENOENT;
1188 } else
1189 pr_warning("Debuginfo analysis failed.\n");
1190 goto end;
1191 }
1192
1193 /* Some variables are found */
1194 fprintf(stdout, "Available variables at %s\n", buf);
1195 for (i = 0; i < ret; i++) {
1196 vl = &vls[i];
1197 /*
1198 * A probe point might be converted to
1199 * several trace points.
1200 */
1201 fprintf(stdout, "\t@<%s+%lu>\n", vl->point.symbol,
1202 vl->point.offset);
1203 zfree(&vl->point.symbol);
1204 nvars = 0;
1205 if (vl->vars) {
1206 strlist__for_each_entry(node, vl->vars) {
1207 var = strchr(node->s, '\t') + 1;
1208 if (strfilter__compare(_filter, var)) {
1209 fprintf(stdout, "\t\t%s\n", node->s);
1210 nvars++;
1211 }
1212 }
1213 strlist__delete(vl->vars);
1214 }
1215 if (nvars == 0)
1216 fprintf(stdout, "\t\t(No matched variables)\n");
1217 }
1218 free(vls);
1219 end:
1220 free(buf);
1221 return ret;
1222 }
1223
1224 /* Show available variables on given probe point */
show_available_vars(struct perf_probe_event * pevs,int npevs,struct strfilter * _filter)1225 int show_available_vars(struct perf_probe_event *pevs, int npevs,
1226 struct strfilter *_filter)
1227 {
1228 int i, ret = 0;
1229 struct debuginfo *dinfo;
1230
1231 ret = init_probe_symbol_maps(pevs->uprobes);
1232 if (ret < 0)
1233 return ret;
1234
1235 dinfo = open_debuginfo(pevs->target, pevs->nsi, false);
1236 if (!dinfo) {
1237 ret = -ENOENT;
1238 goto out;
1239 }
1240
1241 setup_pager();
1242
1243 for (i = 0; i < npevs && ret >= 0; i++)
1244 ret = show_available_vars_at(dinfo, &pevs[i], _filter);
1245
1246 debuginfo__delete(dinfo);
1247 out:
1248 exit_probe_symbol_maps();
1249 return ret;
1250 }
1251
1252 #else /* !HAVE_DWARF_SUPPORT */
1253
debuginfo_cache__exit(void)1254 static void debuginfo_cache__exit(void)
1255 {
1256 }
1257
1258 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)1259 find_perf_probe_point_from_dwarf(struct probe_trace_point *tp __maybe_unused,
1260 struct perf_probe_point *pp __maybe_unused,
1261 bool is_kprobe __maybe_unused)
1262 {
1263 return -ENOSYS;
1264 }
1265
try_to_find_probe_trace_events(struct perf_probe_event * pev,struct probe_trace_event ** tevs __maybe_unused)1266 static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
1267 struct probe_trace_event **tevs __maybe_unused)
1268 {
1269 if (perf_probe_event_need_dwarf(pev)) {
1270 pr_warning("Debuginfo-analysis is not supported.\n");
1271 return -ENOSYS;
1272 }
1273
1274 return 0;
1275 }
1276
show_line_range(struct line_range * lr __maybe_unused,const char * module __maybe_unused,struct nsinfo * nsi __maybe_unused,bool user __maybe_unused)1277 int show_line_range(struct line_range *lr __maybe_unused,
1278 const char *module __maybe_unused,
1279 struct nsinfo *nsi __maybe_unused,
1280 bool user __maybe_unused)
1281 {
1282 pr_warning("Debuginfo-analysis is not supported.\n");
1283 return -ENOSYS;
1284 }
1285
show_available_vars(struct perf_probe_event * pevs __maybe_unused,int npevs __maybe_unused,struct strfilter * filter __maybe_unused)1286 int show_available_vars(struct perf_probe_event *pevs __maybe_unused,
1287 int npevs __maybe_unused,
1288 struct strfilter *filter __maybe_unused)
1289 {
1290 pr_warning("Debuginfo-analysis is not supported.\n");
1291 return -ENOSYS;
1292 }
1293 #endif
1294
line_range__clear(struct line_range * lr)1295 void line_range__clear(struct line_range *lr)
1296 {
1297 zfree(&lr->function);
1298 zfree(&lr->file);
1299 zfree(&lr->path);
1300 zfree(&lr->comp_dir);
1301 intlist__delete(lr->line_list);
1302 }
1303
line_range__init(struct line_range * lr)1304 int line_range__init(struct line_range *lr)
1305 {
1306 memset(lr, 0, sizeof(*lr));
1307 lr->line_list = intlist__new(NULL);
1308 if (!lr->line_list)
1309 return -ENOMEM;
1310 else
1311 return 0;
1312 }
1313
parse_line_num(char ** ptr,int * val,const char * what)1314 static int parse_line_num(char **ptr, int *val, const char *what)
1315 {
1316 const char *start = *ptr;
1317
1318 errno = 0;
1319 *val = strtol(*ptr, ptr, 0);
1320 if (errno || *ptr == start) {
1321 semantic_error("'%s' is not a valid number.\n", what);
1322 return -EINVAL;
1323 }
1324 return 0;
1325 }
1326
1327 /* Check the name is good for event, group or function */
is_c_func_name(const char * name)1328 static bool is_c_func_name(const char *name)
1329 {
1330 if (!isalpha(*name) && *name != '_')
1331 return false;
1332 while (*++name != '\0') {
1333 if (!isalpha(*name) && !isdigit(*name) && *name != '_')
1334 return false;
1335 }
1336 return true;
1337 }
1338
1339 /*
1340 * Stuff 'lr' according to the line range described by 'arg'.
1341 * The line range syntax is described by:
1342 *
1343 * SRC[:SLN[+NUM|-ELN]]
1344 * FNC[@SRC][:SLN[+NUM|-ELN]]
1345 */
parse_line_range_desc(const char * arg,struct line_range * lr)1346 int parse_line_range_desc(const char *arg, struct line_range *lr)
1347 {
1348 char *range, *file, *name = strdup(arg);
1349 int err;
1350
1351 if (!name)
1352 return -ENOMEM;
1353
1354 lr->start = 0;
1355 lr->end = INT_MAX;
1356
1357 range = strchr(name, ':');
1358 if (range) {
1359 *range++ = '\0';
1360
1361 err = parse_line_num(&range, &lr->start, "start line");
1362 if (err)
1363 goto err;
1364
1365 if (*range == '+' || *range == '-') {
1366 const char c = *range++;
1367
1368 err = parse_line_num(&range, &lr->end, "end line");
1369 if (err)
1370 goto err;
1371
1372 if (c == '+') {
1373 lr->end += lr->start;
1374 /*
1375 * Adjust the number of lines here.
1376 * If the number of lines == 1, the
1377 * end of line should be equal to
1378 * the start of line.
1379 */
1380 lr->end--;
1381 }
1382 }
1383
1384 pr_debug("Line range is %d to %d\n", lr->start, lr->end);
1385
1386 err = -EINVAL;
1387 if (lr->start > lr->end) {
1388 semantic_error("Start line must be smaller"
1389 " than end line.\n");
1390 goto err;
1391 }
1392 if (*range != '\0') {
1393 semantic_error("Tailing with invalid str '%s'.\n", range);
1394 goto err;
1395 }
1396 }
1397
1398 file = strchr(name, '@');
1399 if (file) {
1400 *file = '\0';
1401 lr->file = strdup(++file);
1402 if (lr->file == NULL) {
1403 err = -ENOMEM;
1404 goto err;
1405 }
1406 lr->function = name;
1407 } else if (strchr(name, '/') || strchr(name, '.'))
1408 lr->file = name;
1409 else if (is_c_func_name(name))/* We reuse it for checking funcname */
1410 lr->function = name;
1411 else { /* Invalid name */
1412 semantic_error("'%s' is not a valid function name.\n", name);
1413 err = -EINVAL;
1414 goto err;
1415 }
1416
1417 return 0;
1418 err:
1419 free(name);
1420 return err;
1421 }
1422
parse_perf_probe_event_name(char ** arg,struct perf_probe_event * pev)1423 static int parse_perf_probe_event_name(char **arg, struct perf_probe_event *pev)
1424 {
1425 char *ptr;
1426
1427 ptr = strpbrk_esc(*arg, ":");
1428 if (ptr) {
1429 *ptr = '\0';
1430 if (!pev->sdt && !is_c_func_name(*arg))
1431 goto ng_name;
1432 pev->group = strdup_esc(*arg);
1433 if (!pev->group)
1434 return -ENOMEM;
1435 *arg = ptr + 1;
1436 } else
1437 pev->group = NULL;
1438
1439 pev->event = strdup_esc(*arg);
1440 if (pev->event == NULL)
1441 return -ENOMEM;
1442
1443 if (!pev->sdt && !is_c_func_name(pev->event)) {
1444 zfree(&pev->event);
1445 ng_name:
1446 zfree(&pev->group);
1447 semantic_error("%s is bad for event name -it must "
1448 "follow C symbol-naming rule.\n", *arg);
1449 return -EINVAL;
1450 }
1451 return 0;
1452 }
1453
1454 /* Parse probepoint definition. */
parse_perf_probe_point(char * arg,struct perf_probe_event * pev)1455 static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev)
1456 {
1457 struct perf_probe_point *pp = &pev->point;
1458 char *ptr, *tmp;
1459 char c, nc = 0;
1460 bool file_spec = false;
1461 int ret;
1462
1463 /*
1464 * <Syntax>
1465 * perf probe [GRP:][EVENT=]SRC[:LN|;PTN]
1466 * perf probe [GRP:][EVENT=]FUNC[@SRC][+OFFS|%return|:LN|;PAT]
1467 * perf probe %[GRP:]SDT_EVENT
1468 */
1469 if (!arg)
1470 return -EINVAL;
1471
1472 if (is_sdt_event(arg)) {
1473 pev->sdt = true;
1474 if (arg[0] == '%')
1475 arg++;
1476 }
1477
1478 ptr = strpbrk_esc(arg, ";=@+%");
1479 if (pev->sdt) {
1480 if (ptr) {
1481 if (*ptr != '@') {
1482 semantic_error("%s must be an SDT name.\n",
1483 arg);
1484 return -EINVAL;
1485 }
1486 /* This must be a target file name or build id */
1487 tmp = build_id_cache__complement(ptr + 1);
1488 if (tmp) {
1489 pev->target = build_id_cache__origname(tmp);
1490 free(tmp);
1491 } else
1492 pev->target = strdup_esc(ptr + 1);
1493 if (!pev->target)
1494 return -ENOMEM;
1495 *ptr = '\0';
1496 }
1497 ret = parse_perf_probe_event_name(&arg, pev);
1498 if (ret == 0) {
1499 if (asprintf(&pev->point.function, "%%%s", pev->event) < 0)
1500 ret = -errno;
1501 }
1502 return ret;
1503 }
1504
1505 if (ptr && *ptr == '=') { /* Event name */
1506 *ptr = '\0';
1507 tmp = ptr + 1;
1508 ret = parse_perf_probe_event_name(&arg, pev);
1509 if (ret < 0)
1510 return ret;
1511
1512 arg = tmp;
1513 }
1514
1515 /*
1516 * Check arg is function or file name and copy it.
1517 *
1518 * We consider arg to be a file spec if and only if it satisfies
1519 * all of the below criteria::
1520 * - it does not include any of "+@%",
1521 * - it includes one of ":;", and
1522 * - it has a period '.' in the name.
1523 *
1524 * Otherwise, we consider arg to be a function specification.
1525 */
1526 if (!strpbrk_esc(arg, "+@%")) {
1527 ptr = strpbrk_esc(arg, ";:");
1528 /* This is a file spec if it includes a '.' before ; or : */
1529 if (ptr && memchr(arg, '.', ptr - arg))
1530 file_spec = true;
1531 }
1532
1533 ptr = strpbrk_esc(arg, ";:+@%");
1534 if (ptr) {
1535 nc = *ptr;
1536 *ptr++ = '\0';
1537 }
1538
1539 if (arg[0] == '\0')
1540 tmp = NULL;
1541 else {
1542 tmp = strdup_esc(arg);
1543 if (tmp == NULL)
1544 return -ENOMEM;
1545 }
1546
1547 if (file_spec)
1548 pp->file = tmp;
1549 else {
1550 pp->function = tmp;
1551
1552 /*
1553 * Keep pp->function even if this is absolute address,
1554 * so it can mark whether abs_address is valid.
1555 * Which make 'perf probe lib.bin 0x0' possible.
1556 *
1557 * Note that checking length of tmp is not needed
1558 * because when we access tmp[1] we know tmp[0] is '0',
1559 * so tmp[1] should always valid (but could be '\0').
1560 */
1561 if (tmp && !strncmp(tmp, "0x", 2)) {
1562 pp->abs_address = strtoull(pp->function, &tmp, 0);
1563 if (*tmp != '\0') {
1564 semantic_error("Invalid absolute address.\n");
1565 return -EINVAL;
1566 }
1567 }
1568 }
1569
1570 /* Parse other options */
1571 while (ptr) {
1572 arg = ptr;
1573 c = nc;
1574 if (c == ';') { /* Lazy pattern must be the last part */
1575 pp->lazy_line = strdup(arg); /* let leave escapes */
1576 if (pp->lazy_line == NULL)
1577 return -ENOMEM;
1578 break;
1579 }
1580 ptr = strpbrk_esc(arg, ";:+@%");
1581 if (ptr) {
1582 nc = *ptr;
1583 *ptr++ = '\0';
1584 }
1585 switch (c) {
1586 case ':': /* Line number */
1587 pp->line = strtoul(arg, &tmp, 0);
1588 if (*tmp != '\0') {
1589 semantic_error("There is non-digit char"
1590 " in line number.\n");
1591 return -EINVAL;
1592 }
1593 break;
1594 case '+': /* Byte offset from a symbol */
1595 pp->offset = strtoul(arg, &tmp, 0);
1596 if (*tmp != '\0') {
1597 semantic_error("There is non-digit character"
1598 " in offset.\n");
1599 return -EINVAL;
1600 }
1601 break;
1602 case '@': /* File name */
1603 if (pp->file) {
1604 semantic_error("SRC@SRC is not allowed.\n");
1605 return -EINVAL;
1606 }
1607 pp->file = strdup_esc(arg);
1608 if (pp->file == NULL)
1609 return -ENOMEM;
1610 break;
1611 case '%': /* Probe places */
1612 if (strcmp(arg, "return") == 0) {
1613 pp->retprobe = 1;
1614 } else { /* Others not supported yet */
1615 semantic_error("%%%s is not supported.\n", arg);
1616 return -ENOTSUP;
1617 }
1618 break;
1619 default: /* Buggy case */
1620 pr_err("This program has a bug at %s:%d.\n",
1621 __FILE__, __LINE__);
1622 return -ENOTSUP;
1623 break;
1624 }
1625 }
1626
1627 /* Exclusion check */
1628 if (pp->lazy_line && pp->line) {
1629 semantic_error("Lazy pattern can't be used with"
1630 " line number.\n");
1631 return -EINVAL;
1632 }
1633
1634 if (pp->lazy_line && pp->offset) {
1635 semantic_error("Lazy pattern can't be used with offset.\n");
1636 return -EINVAL;
1637 }
1638
1639 if (pp->line && pp->offset) {
1640 semantic_error("Offset can't be used with line number.\n");
1641 return -EINVAL;
1642 }
1643
1644 if (!pp->line && !pp->lazy_line && pp->file && !pp->function) {
1645 semantic_error("File always requires line number or "
1646 "lazy pattern.\n");
1647 return -EINVAL;
1648 }
1649
1650 if (pp->offset && !pp->function) {
1651 semantic_error("Offset requires an entry function.\n");
1652 return -EINVAL;
1653 }
1654
1655 if ((pp->offset || pp->line || pp->lazy_line) && pp->retprobe) {
1656 semantic_error("Offset/Line/Lazy pattern can't be used with "
1657 "return probe.\n");
1658 return -EINVAL;
1659 }
1660
1661 pr_debug("symbol:%s file:%s line:%d offset:%lu return:%d lazy:%s\n",
1662 pp->function, pp->file, pp->line, pp->offset, pp->retprobe,
1663 pp->lazy_line);
1664 return 0;
1665 }
1666
1667 /* Parse perf-probe event argument */
parse_perf_probe_arg(char * str,struct perf_probe_arg * arg)1668 static int parse_perf_probe_arg(char *str, struct perf_probe_arg *arg)
1669 {
1670 char *tmp, *goodname;
1671 struct perf_probe_arg_field **fieldp;
1672
1673 pr_debug("parsing arg: %s into ", str);
1674
1675 tmp = strchr(str, '=');
1676 if (tmp) {
1677 arg->name = strndup(str, tmp - str);
1678 if (arg->name == NULL)
1679 return -ENOMEM;
1680 pr_debug("name:%s ", arg->name);
1681 str = tmp + 1;
1682 }
1683
1684 tmp = strchr(str, '@');
1685 if (tmp && tmp != str && !strcmp(tmp + 1, "user")) { /* user attr */
1686 if (!user_access_is_supported()) {
1687 semantic_error("ftrace does not support user access\n");
1688 return -EINVAL;
1689 }
1690 *tmp = '\0';
1691 arg->user_access = true;
1692 pr_debug("user_access ");
1693 }
1694
1695 tmp = strchr(str, ':');
1696 if (tmp) { /* Type setting */
1697 *tmp = '\0';
1698 arg->type = strdup(tmp + 1);
1699 if (arg->type == NULL)
1700 return -ENOMEM;
1701 pr_debug("type:%s ", arg->type);
1702 }
1703
1704 tmp = strpbrk(str, "-.[");
1705 if (!is_c_varname(str) || !tmp) {
1706 /* A variable, register, symbol or special value */
1707 arg->var = strdup(str);
1708 if (arg->var == NULL)
1709 return -ENOMEM;
1710 pr_debug("%s\n", arg->var);
1711 return 0;
1712 }
1713
1714 /* Structure fields or array element */
1715 arg->var = strndup(str, tmp - str);
1716 if (arg->var == NULL)
1717 return -ENOMEM;
1718 goodname = arg->var;
1719 pr_debug("%s, ", arg->var);
1720 fieldp = &arg->field;
1721
1722 do {
1723 *fieldp = zalloc(sizeof(struct perf_probe_arg_field));
1724 if (*fieldp == NULL)
1725 return -ENOMEM;
1726 if (*tmp == '[') { /* Array */
1727 str = tmp;
1728 (*fieldp)->index = strtol(str + 1, &tmp, 0);
1729 (*fieldp)->ref = true;
1730 if (*tmp != ']' || tmp == str + 1) {
1731 semantic_error("Array index must be a"
1732 " number.\n");
1733 return -EINVAL;
1734 }
1735 tmp++;
1736 if (*tmp == '\0')
1737 tmp = NULL;
1738 } else { /* Structure */
1739 if (*tmp == '.') {
1740 str = tmp + 1;
1741 (*fieldp)->ref = false;
1742 } else if (tmp[1] == '>') {
1743 str = tmp + 2;
1744 (*fieldp)->ref = true;
1745 } else {
1746 semantic_error("Argument parse error: %s\n",
1747 str);
1748 return -EINVAL;
1749 }
1750 tmp = strpbrk(str, "-.[");
1751 }
1752 if (tmp) {
1753 (*fieldp)->name = strndup(str, tmp - str);
1754 if ((*fieldp)->name == NULL)
1755 return -ENOMEM;
1756 if (*str != '[')
1757 goodname = (*fieldp)->name;
1758 pr_debug("%s(%d), ", (*fieldp)->name, (*fieldp)->ref);
1759 fieldp = &(*fieldp)->next;
1760 }
1761 } while (tmp);
1762 (*fieldp)->name = strdup(str);
1763 if ((*fieldp)->name == NULL)
1764 return -ENOMEM;
1765 if (*str != '[')
1766 goodname = (*fieldp)->name;
1767 pr_debug("%s(%d)\n", (*fieldp)->name, (*fieldp)->ref);
1768
1769 /* If no name is specified, set the last field name (not array index)*/
1770 if (!arg->name) {
1771 arg->name = strdup(goodname);
1772 if (arg->name == NULL)
1773 return -ENOMEM;
1774 }
1775 return 0;
1776 }
1777
1778 /* Parse perf-probe event command */
parse_perf_probe_command(const char * cmd,struct perf_probe_event * pev)1779 int parse_perf_probe_command(const char *cmd, struct perf_probe_event *pev)
1780 {
1781 char **argv;
1782 int argc, i, ret = 0;
1783
1784 argv = argv_split(cmd, &argc);
1785 if (!argv) {
1786 pr_debug("Failed to split arguments.\n");
1787 return -ENOMEM;
1788 }
1789 if (argc - 1 > MAX_PROBE_ARGS) {
1790 semantic_error("Too many probe arguments (%d).\n", argc - 1);
1791 ret = -ERANGE;
1792 goto out;
1793 }
1794 /* Parse probe point */
1795 ret = parse_perf_probe_point(argv[0], pev);
1796 if (ret < 0)
1797 goto out;
1798
1799 /* Generate event name if needed */
1800 if (!pev->event && pev->point.function && pev->point.line
1801 && !pev->point.lazy_line && !pev->point.offset) {
1802 if (asprintf(&pev->event, "%s_L%d", pev->point.function,
1803 pev->point.line) < 0) {
1804 ret = -ENOMEM;
1805 goto out;
1806 }
1807 }
1808
1809 /* Copy arguments and ensure return probe has no C argument */
1810 pev->nargs = argc - 1;
1811 pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs);
1812 if (pev->args == NULL) {
1813 ret = -ENOMEM;
1814 goto out;
1815 }
1816 for (i = 0; i < pev->nargs && ret >= 0; i++) {
1817 ret = parse_perf_probe_arg(argv[i + 1], &pev->args[i]);
1818 if (ret >= 0 &&
1819 is_c_varname(pev->args[i].var) && pev->point.retprobe) {
1820 semantic_error("You can't specify local variable for"
1821 " kretprobe.\n");
1822 ret = -EINVAL;
1823 }
1824 }
1825 out:
1826 argv_free(argv);
1827
1828 return ret;
1829 }
1830
1831 /* Returns true if *any* ARG is either C variable, $params or $vars. */
perf_probe_with_var(struct perf_probe_event * pev)1832 bool perf_probe_with_var(struct perf_probe_event *pev)
1833 {
1834 int i = 0;
1835
1836 for (i = 0; i < pev->nargs; i++)
1837 if (is_c_varname(pev->args[i].var) ||
1838 !strcmp(pev->args[i].var, PROBE_ARG_PARAMS) ||
1839 !strcmp(pev->args[i].var, PROBE_ARG_VARS))
1840 return true;
1841 return false;
1842 }
1843
1844 /* Return true if this perf_probe_event requires debuginfo */
perf_probe_event_need_dwarf(struct perf_probe_event * pev)1845 bool perf_probe_event_need_dwarf(struct perf_probe_event *pev)
1846 {
1847 if (pev->point.file || pev->point.line || pev->point.lazy_line)
1848 return true;
1849
1850 if (perf_probe_with_var(pev))
1851 return true;
1852
1853 return false;
1854 }
1855
1856 /* Parse probe_events event into struct probe_point */
parse_probe_trace_command(const char * cmd,struct probe_trace_event * tev)1857 int parse_probe_trace_command(const char *cmd, struct probe_trace_event *tev)
1858 {
1859 struct probe_trace_point *tp = &tev->point;
1860 char pr;
1861 char *p;
1862 char *argv0_str = NULL, *fmt, *fmt1_str, *fmt2_str, *fmt3_str;
1863 int ret, i, argc;
1864 char **argv;
1865
1866 pr_debug("Parsing probe_events: %s\n", cmd);
1867 argv = argv_split(cmd, &argc);
1868 if (!argv) {
1869 pr_debug("Failed to split arguments.\n");
1870 return -ENOMEM;
1871 }
1872 if (argc < 2) {
1873 semantic_error("Too few probe arguments.\n");
1874 ret = -ERANGE;
1875 goto out;
1876 }
1877
1878 /* Scan event and group name. */
1879 argv0_str = strdup(argv[0]);
1880 if (argv0_str == NULL) {
1881 ret = -ENOMEM;
1882 goto out;
1883 }
1884 fmt1_str = strtok_r(argv0_str, ":", &fmt);
1885 fmt2_str = strtok_r(NULL, "/", &fmt);
1886 fmt3_str = strtok_r(NULL, " \t", &fmt);
1887 if (fmt1_str == NULL || fmt2_str == NULL || fmt3_str == NULL) {
1888 semantic_error("Failed to parse event name: %s\n", argv[0]);
1889 ret = -EINVAL;
1890 goto out;
1891 }
1892 pr = fmt1_str[0];
1893 tev->group = strdup(fmt2_str);
1894 tev->event = strdup(fmt3_str);
1895 if (tev->group == NULL || tev->event == NULL) {
1896 ret = -ENOMEM;
1897 goto out;
1898 }
1899 pr_debug("Group:%s Event:%s probe:%c\n", tev->group, tev->event, pr);
1900
1901 tp->retprobe = (pr == 'r');
1902
1903 /* Scan module name(if there), function name and offset */
1904 p = strchr(argv[1], ':');
1905 if (p) {
1906 tp->module = strndup(argv[1], p - argv[1]);
1907 if (!tp->module) {
1908 ret = -ENOMEM;
1909 goto out;
1910 }
1911 tev->uprobes = (tp->module[0] == '/');
1912 p++;
1913 } else
1914 p = argv[1];
1915 fmt1_str = strtok_r(p, "+", &fmt);
1916 /* only the address started with 0x */
1917 if (fmt1_str[0] == '0') {
1918 /*
1919 * Fix a special case:
1920 * if address == 0, kernel reports something like:
1921 * p:probe_libc/abs_0 /lib/libc-2.18.so:0x (null) arg1=%ax
1922 * Newer kernel may fix that, but we want to
1923 * support old kernel also.
1924 */
1925 if (strcmp(fmt1_str, "0x") == 0) {
1926 if (!argv[2] || strcmp(argv[2], "(null)")) {
1927 ret = -EINVAL;
1928 goto out;
1929 }
1930 tp->address = 0;
1931
1932 free(argv[2]);
1933 for (i = 2; argv[i + 1] != NULL; i++)
1934 argv[i] = argv[i + 1];
1935
1936 argv[i] = NULL;
1937 argc -= 1;
1938 } else
1939 tp->address = strtoull(fmt1_str, NULL, 0);
1940 } else {
1941 /* Only the symbol-based probe has offset */
1942 tp->symbol = strdup(fmt1_str);
1943 if (tp->symbol == NULL) {
1944 ret = -ENOMEM;
1945 goto out;
1946 }
1947 fmt2_str = strtok_r(NULL, "", &fmt);
1948 if (fmt2_str == NULL)
1949 tp->offset = 0;
1950 else
1951 tp->offset = strtoul(fmt2_str, NULL, 10);
1952 }
1953
1954 if (tev->uprobes) {
1955 fmt2_str = strchr(p, '(');
1956 if (fmt2_str)
1957 tp->ref_ctr_offset = strtoul(fmt2_str + 1, NULL, 0);
1958 }
1959
1960 tev->nargs = argc - 2;
1961 tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
1962 if (tev->args == NULL) {
1963 ret = -ENOMEM;
1964 goto out;
1965 }
1966 for (i = 0; i < tev->nargs; i++) {
1967 p = strchr(argv[i + 2], '=');
1968 if (p) /* We don't need which register is assigned. */
1969 *p++ = '\0';
1970 else
1971 p = argv[i + 2];
1972 tev->args[i].name = strdup(argv[i + 2]);
1973 /* TODO: parse regs and offset */
1974 tev->args[i].value = strdup(p);
1975 if (tev->args[i].name == NULL || tev->args[i].value == NULL) {
1976 ret = -ENOMEM;
1977 goto out;
1978 }
1979 }
1980 ret = 0;
1981 out:
1982 free(argv0_str);
1983 argv_free(argv);
1984 return ret;
1985 }
1986
1987 /* Compose only probe arg */
synthesize_perf_probe_arg(struct perf_probe_arg * pa)1988 char *synthesize_perf_probe_arg(struct perf_probe_arg *pa)
1989 {
1990 struct perf_probe_arg_field *field = pa->field;
1991 struct strbuf buf;
1992 char *ret = NULL;
1993 int err;
1994
1995 if (strbuf_init(&buf, 64) < 0)
1996 return NULL;
1997
1998 if (pa->name && pa->var)
1999 err = strbuf_addf(&buf, "%s=%s", pa->name, pa->var);
2000 else
2001 err = strbuf_addstr(&buf, pa->name ?: pa->var);
2002 if (err)
2003 goto out;
2004
2005 while (field) {
2006 if (field->name[0] == '[')
2007 err = strbuf_addstr(&buf, field->name);
2008 else
2009 err = strbuf_addf(&buf, "%s%s", field->ref ? "->" : ".",
2010 field->name);
2011 field = field->next;
2012 if (err)
2013 goto out;
2014 }
2015
2016 if (pa->type)
2017 if (strbuf_addf(&buf, ":%s", pa->type) < 0)
2018 goto out;
2019
2020 ret = strbuf_detach(&buf, NULL);
2021 out:
2022 strbuf_release(&buf);
2023 return ret;
2024 }
2025
2026 /* Compose only probe point (not argument) */
synthesize_perf_probe_point(struct perf_probe_point * pp)2027 static char *synthesize_perf_probe_point(struct perf_probe_point *pp)
2028 {
2029 struct strbuf buf;
2030 char *tmp, *ret = NULL;
2031 int len, err = 0;
2032
2033 if (strbuf_init(&buf, 64) < 0)
2034 return NULL;
2035
2036 if (pp->function) {
2037 if (strbuf_addstr(&buf, pp->function) < 0)
2038 goto out;
2039 if (pp->offset)
2040 err = strbuf_addf(&buf, "+%lu", pp->offset);
2041 else if (pp->line)
2042 err = strbuf_addf(&buf, ":%d", pp->line);
2043 else if (pp->retprobe)
2044 err = strbuf_addstr(&buf, "%return");
2045 if (err)
2046 goto out;
2047 }
2048 if (pp->file) {
2049 tmp = pp->file;
2050 len = strlen(tmp);
2051 if (len > 30) {
2052 tmp = strchr(pp->file + len - 30, '/');
2053 tmp = tmp ? tmp + 1 : pp->file + len - 30;
2054 }
2055 err = strbuf_addf(&buf, "@%s", tmp);
2056 if (!err && !pp->function && pp->line)
2057 err = strbuf_addf(&buf, ":%d", pp->line);
2058 }
2059 if (!err)
2060 ret = strbuf_detach(&buf, NULL);
2061 out:
2062 strbuf_release(&buf);
2063 return ret;
2064 }
2065
synthesize_perf_probe_command(struct perf_probe_event * pev)2066 char *synthesize_perf_probe_command(struct perf_probe_event *pev)
2067 {
2068 struct strbuf buf;
2069 char *tmp, *ret = NULL;
2070 int i;
2071
2072 if (strbuf_init(&buf, 64))
2073 return NULL;
2074 if (pev->event)
2075 if (strbuf_addf(&buf, "%s:%s=", pev->group ?: PERFPROBE_GROUP,
2076 pev->event) < 0)
2077 goto out;
2078
2079 tmp = synthesize_perf_probe_point(&pev->point);
2080 if (!tmp || strbuf_addstr(&buf, tmp) < 0) {
2081 free(tmp);
2082 goto out;
2083 }
2084 free(tmp);
2085
2086 for (i = 0; i < pev->nargs; i++) {
2087 tmp = synthesize_perf_probe_arg(pev->args + i);
2088 if (!tmp || strbuf_addf(&buf, " %s", tmp) < 0) {
2089 free(tmp);
2090 goto out;
2091 }
2092 free(tmp);
2093 }
2094
2095 ret = strbuf_detach(&buf, NULL);
2096 out:
2097 strbuf_release(&buf);
2098 return ret;
2099 }
2100
__synthesize_probe_trace_arg_ref(struct probe_trace_arg_ref * ref,struct strbuf * buf,int depth)2101 static int __synthesize_probe_trace_arg_ref(struct probe_trace_arg_ref *ref,
2102 struct strbuf *buf, int depth)
2103 {
2104 int err;
2105 if (ref->next) {
2106 depth = __synthesize_probe_trace_arg_ref(ref->next, buf,
2107 depth + 1);
2108 if (depth < 0)
2109 return depth;
2110 }
2111 if (ref->user_access)
2112 err = strbuf_addf(buf, "%s%ld(", "+u", ref->offset);
2113 else
2114 err = strbuf_addf(buf, "%+ld(", ref->offset);
2115 return (err < 0) ? err : depth;
2116 }
2117
synthesize_probe_trace_arg(struct probe_trace_arg * arg,struct strbuf * buf)2118 static int synthesize_probe_trace_arg(struct probe_trace_arg *arg,
2119 struct strbuf *buf)
2120 {
2121 struct probe_trace_arg_ref *ref = arg->ref;
2122 int depth = 0, err;
2123
2124 /* Argument name or separator */
2125 if (arg->name)
2126 err = strbuf_addf(buf, " %s=", arg->name);
2127 else
2128 err = strbuf_addch(buf, ' ');
2129 if (err)
2130 return err;
2131
2132 /* Special case: @XXX */
2133 if (arg->value[0] == '@' && arg->ref)
2134 ref = ref->next;
2135
2136 /* Dereferencing arguments */
2137 if (ref) {
2138 depth = __synthesize_probe_trace_arg_ref(ref, buf, 1);
2139 if (depth < 0)
2140 return depth;
2141 }
2142
2143 /* Print argument value */
2144 if (arg->value[0] == '@' && arg->ref)
2145 err = strbuf_addf(buf, "%s%+ld", arg->value, arg->ref->offset);
2146 else
2147 err = strbuf_addstr(buf, arg->value);
2148
2149 /* Closing */
2150 while (!err && depth--)
2151 err = strbuf_addch(buf, ')');
2152
2153 /* Print argument type */
2154 if (!err && arg->type)
2155 err = strbuf_addf(buf, ":%s", arg->type);
2156
2157 return err;
2158 }
2159
2160 static int
synthesize_probe_trace_args(struct probe_trace_event * tev,struct strbuf * buf)2161 synthesize_probe_trace_args(struct probe_trace_event *tev, struct strbuf *buf)
2162 {
2163 int i, ret = 0;
2164
2165 for (i = 0; i < tev->nargs && ret >= 0; i++)
2166 ret = synthesize_probe_trace_arg(&tev->args[i], buf);
2167
2168 return ret;
2169 }
2170
2171 static int
synthesize_uprobe_trace_def(struct probe_trace_point * tp,struct strbuf * buf)2172 synthesize_uprobe_trace_def(struct probe_trace_point *tp, struct strbuf *buf)
2173 {
2174 int err;
2175
2176 /* Uprobes must have tp->module */
2177 if (!tp->module)
2178 return -EINVAL;
2179 /*
2180 * If tp->address == 0, then this point must be a
2181 * absolute address uprobe.
2182 * try_to_find_absolute_address() should have made
2183 * tp->symbol to "0x0".
2184 */
2185 if (!tp->address && (!tp->symbol || strcmp(tp->symbol, "0x0")))
2186 return -EINVAL;
2187
2188 /* Use the tp->address for uprobes */
2189 err = strbuf_addf(buf, "%s:0x%" PRIx64, tp->module, tp->address);
2190
2191 if (err >= 0 && tp->ref_ctr_offset) {
2192 if (!uprobe_ref_ctr_is_supported())
2193 return -EINVAL;
2194 err = strbuf_addf(buf, "(0x%lx)", tp->ref_ctr_offset);
2195 }
2196 return err >= 0 ? 0 : err;
2197 }
2198
2199 static int
synthesize_kprobe_trace_def(struct probe_trace_point * tp,struct strbuf * buf)2200 synthesize_kprobe_trace_def(struct probe_trace_point *tp, struct strbuf *buf)
2201 {
2202 if (!strncmp(tp->symbol, "0x", 2)) {
2203 /* Absolute address. See try_to_find_absolute_address() */
2204 return strbuf_addf(buf, "%s%s0x%" PRIx64, tp->module ?: "",
2205 tp->module ? ":" : "", tp->address);
2206 } else {
2207 return strbuf_addf(buf, "%s%s%s+%lu", tp->module ?: "",
2208 tp->module ? ":" : "", tp->symbol, tp->offset);
2209 }
2210 }
2211
synthesize_probe_trace_command(struct probe_trace_event * tev)2212 char *synthesize_probe_trace_command(struct probe_trace_event *tev)
2213 {
2214 struct probe_trace_point *tp = &tev->point;
2215 struct strbuf buf;
2216 char *ret = NULL;
2217 int err;
2218
2219 if (strbuf_init(&buf, 32) < 0)
2220 return NULL;
2221
2222 if (strbuf_addf(&buf, "%c:%s/%s ", tp->retprobe ? 'r' : 'p',
2223 tev->group, tev->event) < 0)
2224 goto error;
2225
2226 if (tev->uprobes)
2227 err = synthesize_uprobe_trace_def(tp, &buf);
2228 else
2229 err = synthesize_kprobe_trace_def(tp, &buf);
2230
2231 if (err >= 0)
2232 err = synthesize_probe_trace_args(tev, &buf);
2233
2234 if (err >= 0)
2235 ret = strbuf_detach(&buf, NULL);
2236 error:
2237 strbuf_release(&buf);
2238 return ret;
2239 }
2240
find_perf_probe_point_from_map(struct probe_trace_point * tp,struct perf_probe_point * pp,bool is_kprobe)2241 static int find_perf_probe_point_from_map(struct probe_trace_point *tp,
2242 struct perf_probe_point *pp,
2243 bool is_kprobe)
2244 {
2245 struct symbol *sym = NULL;
2246 struct map *map = NULL;
2247 u64 addr = tp->address;
2248 int ret = -ENOENT;
2249
2250 if (!is_kprobe) {
2251 map = dso__new_map(tp->module);
2252 if (!map)
2253 goto out;
2254 sym = map__find_symbol(map, addr);
2255 } else {
2256 if (tp->symbol && !addr) {
2257 if (kernel_get_symbol_address_by_name(tp->symbol,
2258 &addr, true, false) < 0)
2259 goto out;
2260 }
2261 if (addr) {
2262 addr += tp->offset;
2263 sym = machine__find_kernel_symbol(host_machine, addr, &map);
2264 }
2265 }
2266
2267 if (!sym)
2268 goto out;
2269
2270 pp->retprobe = tp->retprobe;
2271 pp->offset = addr - map__unmap_ip(map, sym->start);
2272 pp->function = strdup(sym->name);
2273 ret = pp->function ? 0 : -ENOMEM;
2274
2275 out:
2276 if (map && !is_kprobe) {
2277 map__put(map);
2278 }
2279
2280 return ret;
2281 }
2282
convert_to_perf_probe_point(struct probe_trace_point * tp,struct perf_probe_point * pp,bool is_kprobe)2283 static int convert_to_perf_probe_point(struct probe_trace_point *tp,
2284 struct perf_probe_point *pp,
2285 bool is_kprobe)
2286 {
2287 char buf[128];
2288 int ret;
2289
2290 ret = find_perf_probe_point_from_dwarf(tp, pp, is_kprobe);
2291 if (!ret)
2292 return 0;
2293 ret = find_perf_probe_point_from_map(tp, pp, is_kprobe);
2294 if (!ret)
2295 return 0;
2296
2297 pr_debug("Failed to find probe point from both of dwarf and map.\n");
2298
2299 if (tp->symbol) {
2300 pp->function = strdup(tp->symbol);
2301 pp->offset = tp->offset;
2302 } else {
2303 ret = e_snprintf(buf, 128, "0x%" PRIx64, tp->address);
2304 if (ret < 0)
2305 return ret;
2306 pp->function = strdup(buf);
2307 pp->offset = 0;
2308 }
2309 if (pp->function == NULL)
2310 return -ENOMEM;
2311
2312 pp->retprobe = tp->retprobe;
2313
2314 return 0;
2315 }
2316
convert_to_perf_probe_event(struct probe_trace_event * tev,struct perf_probe_event * pev,bool is_kprobe)2317 static int convert_to_perf_probe_event(struct probe_trace_event *tev,
2318 struct perf_probe_event *pev, bool is_kprobe)
2319 {
2320 struct strbuf buf = STRBUF_INIT;
2321 int i, ret;
2322
2323 /* Convert event/group name */
2324 pev->event = strdup(tev->event);
2325 pev->group = strdup(tev->group);
2326 if (pev->event == NULL || pev->group == NULL)
2327 return -ENOMEM;
2328
2329 /* Convert trace_point to probe_point */
2330 ret = convert_to_perf_probe_point(&tev->point, &pev->point, is_kprobe);
2331 if (ret < 0)
2332 return ret;
2333
2334 /* Convert trace_arg to probe_arg */
2335 pev->nargs = tev->nargs;
2336 pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs);
2337 if (pev->args == NULL)
2338 return -ENOMEM;
2339 for (i = 0; i < tev->nargs && ret >= 0; i++) {
2340 if (tev->args[i].name)
2341 pev->args[i].name = strdup(tev->args[i].name);
2342 else {
2343 if ((ret = strbuf_init(&buf, 32)) < 0)
2344 goto error;
2345 ret = synthesize_probe_trace_arg(&tev->args[i], &buf);
2346 pev->args[i].name = strbuf_detach(&buf, NULL);
2347 }
2348 if (pev->args[i].name == NULL && ret >= 0)
2349 ret = -ENOMEM;
2350 }
2351 error:
2352 if (ret < 0)
2353 clear_perf_probe_event(pev);
2354
2355 return ret;
2356 }
2357
clear_perf_probe_event(struct perf_probe_event * pev)2358 void clear_perf_probe_event(struct perf_probe_event *pev)
2359 {
2360 struct perf_probe_arg_field *field, *next;
2361 int i;
2362
2363 zfree(&pev->event);
2364 zfree(&pev->group);
2365 zfree(&pev->target);
2366 clear_perf_probe_point(&pev->point);
2367
2368 for (i = 0; i < pev->nargs; i++) {
2369 zfree(&pev->args[i].name);
2370 zfree(&pev->args[i].var);
2371 zfree(&pev->args[i].type);
2372 field = pev->args[i].field;
2373 while (field) {
2374 next = field->next;
2375 zfree(&field->name);
2376 free(field);
2377 field = next;
2378 }
2379 }
2380 pev->nargs = 0;
2381 zfree(&pev->args);
2382 }
2383
2384 #define strdup_or_goto(str, label) \
2385 ({ char *__p = NULL; if (str && !(__p = strdup(str))) goto label; __p; })
2386
perf_probe_point__copy(struct perf_probe_point * dst,struct perf_probe_point * src)2387 static int perf_probe_point__copy(struct perf_probe_point *dst,
2388 struct perf_probe_point *src)
2389 {
2390 dst->file = strdup_or_goto(src->file, out_err);
2391 dst->function = strdup_or_goto(src->function, out_err);
2392 dst->lazy_line = strdup_or_goto(src->lazy_line, out_err);
2393 dst->line = src->line;
2394 dst->retprobe = src->retprobe;
2395 dst->offset = src->offset;
2396 return 0;
2397
2398 out_err:
2399 clear_perf_probe_point(dst);
2400 return -ENOMEM;
2401 }
2402
perf_probe_arg__copy(struct perf_probe_arg * dst,struct perf_probe_arg * src)2403 static int perf_probe_arg__copy(struct perf_probe_arg *dst,
2404 struct perf_probe_arg *src)
2405 {
2406 struct perf_probe_arg_field *field, **ppfield;
2407
2408 dst->name = strdup_or_goto(src->name, out_err);
2409 dst->var = strdup_or_goto(src->var, out_err);
2410 dst->type = strdup_or_goto(src->type, out_err);
2411
2412 field = src->field;
2413 ppfield = &(dst->field);
2414 while (field) {
2415 *ppfield = zalloc(sizeof(*field));
2416 if (!*ppfield)
2417 goto out_err;
2418 (*ppfield)->name = strdup_or_goto(field->name, out_err);
2419 (*ppfield)->index = field->index;
2420 (*ppfield)->ref = field->ref;
2421 field = field->next;
2422 ppfield = &((*ppfield)->next);
2423 }
2424 return 0;
2425 out_err:
2426 return -ENOMEM;
2427 }
2428
perf_probe_event__copy(struct perf_probe_event * dst,struct perf_probe_event * src)2429 int perf_probe_event__copy(struct perf_probe_event *dst,
2430 struct perf_probe_event *src)
2431 {
2432 int i;
2433
2434 dst->event = strdup_or_goto(src->event, out_err);
2435 dst->group = strdup_or_goto(src->group, out_err);
2436 dst->target = strdup_or_goto(src->target, out_err);
2437 dst->uprobes = src->uprobes;
2438
2439 if (perf_probe_point__copy(&dst->point, &src->point) < 0)
2440 goto out_err;
2441
2442 dst->args = zalloc(sizeof(struct perf_probe_arg) * src->nargs);
2443 if (!dst->args)
2444 goto out_err;
2445 dst->nargs = src->nargs;
2446
2447 for (i = 0; i < src->nargs; i++)
2448 if (perf_probe_arg__copy(&dst->args[i], &src->args[i]) < 0)
2449 goto out_err;
2450 return 0;
2451
2452 out_err:
2453 clear_perf_probe_event(dst);
2454 return -ENOMEM;
2455 }
2456
clear_probe_trace_event(struct probe_trace_event * tev)2457 void clear_probe_trace_event(struct probe_trace_event *tev)
2458 {
2459 struct probe_trace_arg_ref *ref, *next;
2460 int i;
2461
2462 zfree(&tev->event);
2463 zfree(&tev->group);
2464 zfree(&tev->point.symbol);
2465 zfree(&tev->point.realname);
2466 zfree(&tev->point.module);
2467 for (i = 0; i < tev->nargs; i++) {
2468 zfree(&tev->args[i].name);
2469 zfree(&tev->args[i].value);
2470 zfree(&tev->args[i].type);
2471 ref = tev->args[i].ref;
2472 while (ref) {
2473 next = ref->next;
2474 free(ref);
2475 ref = next;
2476 }
2477 }
2478 zfree(&tev->args);
2479 tev->nargs = 0;
2480 }
2481
2482 struct kprobe_blacklist_node {
2483 struct list_head list;
2484 u64 start;
2485 u64 end;
2486 char *symbol;
2487 };
2488
kprobe_blacklist__delete(struct list_head * blacklist)2489 static void kprobe_blacklist__delete(struct list_head *blacklist)
2490 {
2491 struct kprobe_blacklist_node *node;
2492
2493 while (!list_empty(blacklist)) {
2494 node = list_first_entry(blacklist,
2495 struct kprobe_blacklist_node, list);
2496 list_del_init(&node->list);
2497 zfree(&node->symbol);
2498 free(node);
2499 }
2500 }
2501
kprobe_blacklist__load(struct list_head * blacklist)2502 static int kprobe_blacklist__load(struct list_head *blacklist)
2503 {
2504 struct kprobe_blacklist_node *node;
2505 const char *__debugfs = debugfs__mountpoint();
2506 char buf[PATH_MAX], *p;
2507 FILE *fp;
2508 int ret;
2509
2510 if (__debugfs == NULL)
2511 return -ENOTSUP;
2512
2513 ret = e_snprintf(buf, PATH_MAX, "%s/kprobes/blacklist", __debugfs);
2514 if (ret < 0)
2515 return ret;
2516
2517 fp = fopen(buf, "r");
2518 if (!fp)
2519 return -errno;
2520
2521 ret = 0;
2522 while (fgets(buf, PATH_MAX, fp)) {
2523 node = zalloc(sizeof(*node));
2524 if (!node) {
2525 ret = -ENOMEM;
2526 break;
2527 }
2528 INIT_LIST_HEAD(&node->list);
2529 list_add_tail(&node->list, blacklist);
2530 if (sscanf(buf, "0x%" PRIx64 "-0x%" PRIx64, &node->start, &node->end) != 2) {
2531 ret = -EINVAL;
2532 break;
2533 }
2534 p = strchr(buf, '\t');
2535 if (p) {
2536 p++;
2537 if (p[strlen(p) - 1] == '\n')
2538 p[strlen(p) - 1] = '\0';
2539 } else
2540 p = (char *)"unknown";
2541 node->symbol = strdup(p);
2542 if (!node->symbol) {
2543 ret = -ENOMEM;
2544 break;
2545 }
2546 pr_debug2("Blacklist: 0x%" PRIx64 "-0x%" PRIx64 ", %s\n",
2547 node->start, node->end, node->symbol);
2548 ret++;
2549 }
2550 if (ret < 0)
2551 kprobe_blacklist__delete(blacklist);
2552 fclose(fp);
2553
2554 return ret;
2555 }
2556
2557 static struct kprobe_blacklist_node *
kprobe_blacklist__find_by_address(struct list_head * blacklist,u64 address)2558 kprobe_blacklist__find_by_address(struct list_head *blacklist, u64 address)
2559 {
2560 struct kprobe_blacklist_node *node;
2561
2562 list_for_each_entry(node, blacklist, list) {
2563 if (node->start <= address && address < node->end)
2564 return node;
2565 }
2566
2567 return NULL;
2568 }
2569
2570 static LIST_HEAD(kprobe_blacklist);
2571
kprobe_blacklist__init(void)2572 static void kprobe_blacklist__init(void)
2573 {
2574 if (!list_empty(&kprobe_blacklist))
2575 return;
2576
2577 if (kprobe_blacklist__load(&kprobe_blacklist) < 0)
2578 pr_debug("No kprobe blacklist support, ignored\n");
2579 }
2580
kprobe_blacklist__release(void)2581 static void kprobe_blacklist__release(void)
2582 {
2583 kprobe_blacklist__delete(&kprobe_blacklist);
2584 }
2585
kprobe_blacklist__listed(u64 address)2586 static bool kprobe_blacklist__listed(u64 address)
2587 {
2588 return !!kprobe_blacklist__find_by_address(&kprobe_blacklist, address);
2589 }
2590
perf_probe_event__sprintf(const char * group,const char * event,struct perf_probe_event * pev,const char * module,struct strbuf * result)2591 static int perf_probe_event__sprintf(const char *group, const char *event,
2592 struct perf_probe_event *pev,
2593 const char *module,
2594 struct strbuf *result)
2595 {
2596 int i, ret;
2597 char *buf;
2598
2599 if (asprintf(&buf, "%s:%s", group, event) < 0)
2600 return -errno;
2601 ret = strbuf_addf(result, " %-20s (on ", buf);
2602 free(buf);
2603 if (ret)
2604 return ret;
2605
2606 /* Synthesize only event probe point */
2607 buf = synthesize_perf_probe_point(&pev->point);
2608 if (!buf)
2609 return -ENOMEM;
2610 ret = strbuf_addstr(result, buf);
2611 free(buf);
2612
2613 if (!ret && module)
2614 ret = strbuf_addf(result, " in %s", module);
2615
2616 if (!ret && pev->nargs > 0) {
2617 ret = strbuf_add(result, " with", 5);
2618 for (i = 0; !ret && i < pev->nargs; i++) {
2619 buf = synthesize_perf_probe_arg(&pev->args[i]);
2620 if (!buf)
2621 return -ENOMEM;
2622 ret = strbuf_addf(result, " %s", buf);
2623 free(buf);
2624 }
2625 }
2626 if (!ret)
2627 ret = strbuf_addch(result, ')');
2628
2629 return ret;
2630 }
2631
2632 /* Show an event */
show_perf_probe_event(const char * group,const char * event,struct perf_probe_event * pev,const char * module,bool use_stdout)2633 int show_perf_probe_event(const char *group, const char *event,
2634 struct perf_probe_event *pev,
2635 const char *module, bool use_stdout)
2636 {
2637 struct strbuf buf = STRBUF_INIT;
2638 int ret;
2639
2640 ret = perf_probe_event__sprintf(group, event, pev, module, &buf);
2641 if (ret >= 0) {
2642 if (use_stdout)
2643 printf("%s\n", buf.buf);
2644 else
2645 pr_info("%s\n", buf.buf);
2646 }
2647 strbuf_release(&buf);
2648
2649 return ret;
2650 }
2651
filter_probe_trace_event(struct probe_trace_event * tev,struct strfilter * filter)2652 static bool filter_probe_trace_event(struct probe_trace_event *tev,
2653 struct strfilter *filter)
2654 {
2655 char tmp[128];
2656
2657 /* At first, check the event name itself */
2658 if (strfilter__compare(filter, tev->event))
2659 return true;
2660
2661 /* Next, check the combination of name and group */
2662 if (e_snprintf(tmp, 128, "%s:%s", tev->group, tev->event) < 0)
2663 return false;
2664 return strfilter__compare(filter, tmp);
2665 }
2666
__show_perf_probe_events(int fd,bool is_kprobe,struct strfilter * filter)2667 static int __show_perf_probe_events(int fd, bool is_kprobe,
2668 struct strfilter *filter)
2669 {
2670 int ret = 0;
2671 struct probe_trace_event tev;
2672 struct perf_probe_event pev;
2673 struct strlist *rawlist;
2674 struct str_node *ent;
2675
2676 memset(&tev, 0, sizeof(tev));
2677 memset(&pev, 0, sizeof(pev));
2678
2679 rawlist = probe_file__get_rawlist(fd);
2680 if (!rawlist)
2681 return -ENOMEM;
2682
2683 strlist__for_each_entry(ent, rawlist) {
2684 ret = parse_probe_trace_command(ent->s, &tev);
2685 if (ret >= 0) {
2686 if (!filter_probe_trace_event(&tev, filter))
2687 goto next;
2688 ret = convert_to_perf_probe_event(&tev, &pev,
2689 is_kprobe);
2690 if (ret < 0)
2691 goto next;
2692 ret = show_perf_probe_event(pev.group, pev.event,
2693 &pev, tev.point.module,
2694 true);
2695 }
2696 next:
2697 clear_perf_probe_event(&pev);
2698 clear_probe_trace_event(&tev);
2699 if (ret < 0)
2700 break;
2701 }
2702 strlist__delete(rawlist);
2703 /* Cleanup cached debuginfo if needed */
2704 debuginfo_cache__exit();
2705
2706 return ret;
2707 }
2708
2709 /* List up current perf-probe events */
show_perf_probe_events(struct strfilter * filter)2710 int show_perf_probe_events(struct strfilter *filter)
2711 {
2712 int kp_fd, up_fd, ret;
2713
2714 setup_pager();
2715
2716 if (probe_conf.cache)
2717 return probe_cache__show_all_caches(filter);
2718
2719 ret = init_probe_symbol_maps(false);
2720 if (ret < 0)
2721 return ret;
2722
2723 ret = probe_file__open_both(&kp_fd, &up_fd, 0);
2724 if (ret < 0)
2725 return ret;
2726
2727 if (kp_fd >= 0)
2728 ret = __show_perf_probe_events(kp_fd, true, filter);
2729 if (up_fd >= 0 && ret >= 0)
2730 ret = __show_perf_probe_events(up_fd, false, filter);
2731 if (kp_fd > 0)
2732 close(kp_fd);
2733 if (up_fd > 0)
2734 close(up_fd);
2735 exit_probe_symbol_maps();
2736
2737 return ret;
2738 }
2739
get_new_event_name(char * buf,size_t len,const char * base,struct strlist * namelist,bool ret_event,bool allow_suffix)2740 static int get_new_event_name(char *buf, size_t len, const char *base,
2741 struct strlist *namelist, bool ret_event,
2742 bool allow_suffix)
2743 {
2744 int i, ret;
2745 char *p, *nbase;
2746
2747 if (*base == '.')
2748 base++;
2749 nbase = strdup(base);
2750 if (!nbase)
2751 return -ENOMEM;
2752
2753 /* Cut off the dot suffixes (e.g. .const, .isra) and version suffixes */
2754 p = strpbrk(nbase, ".@");
2755 if (p && p != nbase)
2756 *p = '\0';
2757
2758 /* Try no suffix number */
2759 ret = e_snprintf(buf, len, "%s%s", nbase, ret_event ? "__return" : "");
2760 if (ret < 0) {
2761 pr_debug("snprintf() failed: %d\n", ret);
2762 goto out;
2763 }
2764 if (!strlist__has_entry(namelist, buf))
2765 goto out;
2766
2767 if (!allow_suffix) {
2768 pr_warning("Error: event \"%s\" already exists.\n"
2769 " Hint: Remove existing event by 'perf probe -d'\n"
2770 " or force duplicates by 'perf probe -f'\n"
2771 " or set 'force=yes' in BPF source.\n",
2772 buf);
2773 ret = -EEXIST;
2774 goto out;
2775 }
2776
2777 /* Try to add suffix */
2778 for (i = 1; i < MAX_EVENT_INDEX; i++) {
2779 ret = e_snprintf(buf, len, "%s_%d", nbase, i);
2780 if (ret < 0) {
2781 pr_debug("snprintf() failed: %d\n", ret);
2782 goto out;
2783 }
2784 if (!strlist__has_entry(namelist, buf))
2785 break;
2786 }
2787 if (i == MAX_EVENT_INDEX) {
2788 pr_warning("Too many events are on the same function.\n");
2789 ret = -ERANGE;
2790 }
2791
2792 out:
2793 free(nbase);
2794
2795 /* Final validation */
2796 if (ret >= 0 && !is_c_func_name(buf)) {
2797 pr_warning("Internal error: \"%s\" is an invalid event name.\n",
2798 buf);
2799 ret = -EINVAL;
2800 }
2801
2802 return ret;
2803 }
2804
2805 /* Warn if the current kernel's uprobe implementation is old */
warn_uprobe_event_compat(struct probe_trace_event * tev)2806 static void warn_uprobe_event_compat(struct probe_trace_event *tev)
2807 {
2808 int i;
2809 char *buf = synthesize_probe_trace_command(tev);
2810 struct probe_trace_point *tp = &tev->point;
2811
2812 if (tp->ref_ctr_offset && !uprobe_ref_ctr_is_supported()) {
2813 pr_warning("A semaphore is associated with %s:%s and "
2814 "seems your kernel doesn't support it.\n",
2815 tev->group, tev->event);
2816 }
2817
2818 /* Old uprobe event doesn't support memory dereference */
2819 if (!tev->uprobes || tev->nargs == 0 || !buf)
2820 goto out;
2821
2822 for (i = 0; i < tev->nargs; i++) {
2823 if (strchr(tev->args[i].value, '@')) {
2824 pr_warning("%s accesses a variable by symbol name, but that is not supported for user application probe.\n",
2825 tev->args[i].value);
2826 break;
2827 }
2828 if (strglobmatch(tev->args[i].value, "[$+-]*")) {
2829 pr_warning("Please upgrade your kernel to at least 3.14 to have access to feature %s\n",
2830 tev->args[i].value);
2831 break;
2832 }
2833 }
2834 out:
2835 free(buf);
2836 }
2837
2838 /* 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)2839 static int probe_trace_event__set_name(struct probe_trace_event *tev,
2840 struct perf_probe_event *pev,
2841 struct strlist *namelist,
2842 bool allow_suffix)
2843 {
2844 const char *event, *group;
2845 char buf[64];
2846 int ret;
2847
2848 /* If probe_event or trace_event already have the name, reuse it */
2849 if (pev->event && !pev->sdt)
2850 event = pev->event;
2851 else if (tev->event)
2852 event = tev->event;
2853 else {
2854 /* Or generate new one from probe point */
2855 if (pev->point.function &&
2856 (strncmp(pev->point.function, "0x", 2) != 0) &&
2857 !strisglob(pev->point.function))
2858 event = pev->point.function;
2859 else
2860 event = tev->point.realname;
2861 }
2862 if (pev->group && !pev->sdt)
2863 group = pev->group;
2864 else if (tev->group)
2865 group = tev->group;
2866 else
2867 group = PERFPROBE_GROUP;
2868
2869 /* Get an unused new event name */
2870 ret = get_new_event_name(buf, 64, event, namelist,
2871 tev->point.retprobe, allow_suffix);
2872 if (ret < 0)
2873 return ret;
2874
2875 event = buf;
2876
2877 tev->event = strdup(event);
2878 tev->group = strdup(group);
2879 if (tev->event == NULL || tev->group == NULL)
2880 return -ENOMEM;
2881
2882 /*
2883 * Add new event name to namelist if multiprobe event is NOT
2884 * supported, since we have to use new event name for following
2885 * probes in that case.
2886 */
2887 if (!multiprobe_event_is_supported())
2888 strlist__add(namelist, event);
2889 return 0;
2890 }
2891
__open_probe_file_and_namelist(bool uprobe,struct strlist ** namelist)2892 static int __open_probe_file_and_namelist(bool uprobe,
2893 struct strlist **namelist)
2894 {
2895 int fd;
2896
2897 fd = probe_file__open(PF_FL_RW | (uprobe ? PF_FL_UPROBE : 0));
2898 if (fd < 0)
2899 return fd;
2900
2901 /* Get current event names */
2902 *namelist = probe_file__get_namelist(fd);
2903 if (!(*namelist)) {
2904 pr_debug("Failed to get current event list.\n");
2905 close(fd);
2906 return -ENOMEM;
2907 }
2908 return fd;
2909 }
2910
__add_probe_trace_events(struct perf_probe_event * pev,struct probe_trace_event * tevs,int ntevs,bool allow_suffix)2911 static int __add_probe_trace_events(struct perf_probe_event *pev,
2912 struct probe_trace_event *tevs,
2913 int ntevs, bool allow_suffix)
2914 {
2915 int i, fd[2] = {-1, -1}, up, ret;
2916 struct probe_trace_event *tev = NULL;
2917 struct probe_cache *cache = NULL;
2918 struct strlist *namelist[2] = {NULL, NULL};
2919 struct nscookie nsc;
2920
2921 up = pev->uprobes ? 1 : 0;
2922 fd[up] = __open_probe_file_and_namelist(up, &namelist[up]);
2923 if (fd[up] < 0)
2924 return fd[up];
2925
2926 ret = 0;
2927 for (i = 0; i < ntevs; i++) {
2928 tev = &tevs[i];
2929 up = tev->uprobes ? 1 : 0;
2930 if (fd[up] == -1) { /* Open the kprobe/uprobe_events */
2931 fd[up] = __open_probe_file_and_namelist(up,
2932 &namelist[up]);
2933 if (fd[up] < 0)
2934 goto close_out;
2935 }
2936 /* Skip if the symbol is out of .text or blacklisted */
2937 if (!tev->point.symbol && !pev->uprobes)
2938 continue;
2939
2940 /* Set new name for tev (and update namelist) */
2941 ret = probe_trace_event__set_name(tev, pev, namelist[up],
2942 allow_suffix);
2943 if (ret < 0)
2944 break;
2945
2946 nsinfo__mountns_enter(pev->nsi, &nsc);
2947 ret = probe_file__add_event(fd[up], tev);
2948 nsinfo__mountns_exit(&nsc);
2949 if (ret < 0)
2950 break;
2951
2952 /*
2953 * Probes after the first probe which comes from same
2954 * user input are always allowed to add suffix, because
2955 * there might be several addresses corresponding to
2956 * one code line.
2957 */
2958 allow_suffix = true;
2959 }
2960 if (ret == -EINVAL && pev->uprobes)
2961 warn_uprobe_event_compat(tev);
2962 if (ret == 0 && probe_conf.cache) {
2963 cache = probe_cache__new(pev->target, pev->nsi);
2964 if (!cache ||
2965 probe_cache__add_entry(cache, pev, tevs, ntevs) < 0 ||
2966 probe_cache__commit(cache) < 0)
2967 pr_warning("Failed to add event to probe cache\n");
2968 probe_cache__delete(cache);
2969 }
2970
2971 close_out:
2972 for (up = 0; up < 2; up++) {
2973 strlist__delete(namelist[up]);
2974 if (fd[up] >= 0)
2975 close(fd[up]);
2976 }
2977 return ret;
2978 }
2979
find_probe_functions(struct map * map,char * name,struct symbol ** syms)2980 static int find_probe_functions(struct map *map, char *name,
2981 struct symbol **syms)
2982 {
2983 int found = 0;
2984 struct symbol *sym;
2985 struct rb_node *tmp;
2986 const char *norm, *ver;
2987 char *buf = NULL;
2988 bool cut_version = true;
2989
2990 if (map__load(map) < 0)
2991 return -EACCES; /* Possible permission error to load symbols */
2992
2993 /* If user gives a version, don't cut off the version from symbols */
2994 if (strchr(name, '@'))
2995 cut_version = false;
2996
2997 map__for_each_symbol(map, sym, tmp) {
2998 norm = arch__normalize_symbol_name(sym->name);
2999 if (!norm)
3000 continue;
3001
3002 if (cut_version) {
3003 /* We don't care about default symbol or not */
3004 ver = strchr(norm, '@');
3005 if (ver) {
3006 buf = strndup(norm, ver - norm);
3007 if (!buf)
3008 return -ENOMEM;
3009 norm = buf;
3010 }
3011 }
3012
3013 if (strglobmatch(norm, name)) {
3014 found++;
3015 if (syms && found < probe_conf.max_probes)
3016 syms[found - 1] = sym;
3017 }
3018 if (buf)
3019 zfree(&buf);
3020 }
3021
3022 return found;
3023 }
3024
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)3025 void __weak arch__fix_tev_from_maps(struct perf_probe_event *pev __maybe_unused,
3026 struct probe_trace_event *tev __maybe_unused,
3027 struct map *map __maybe_unused,
3028 struct symbol *sym __maybe_unused) { }
3029
3030
pr_kallsyms_access_error(void)3031 static void pr_kallsyms_access_error(void)
3032 {
3033 pr_err("Please ensure you can read the /proc/kallsyms symbol addresses.\n"
3034 "If /proc/sys/kernel/kptr_restrict is '2', you can not read\n"
3035 "kernel symbol addresses even if you are a superuser. Please change\n"
3036 "it to '1'. If kptr_restrict is '1', the superuser can read the\n"
3037 "symbol addresses.\n"
3038 "In that case, please run this command again with sudo.\n");
3039 }
3040
3041 /*
3042 * Find probe function addresses from map.
3043 * Return an error or the number of found probe_trace_event
3044 */
find_probe_trace_events_from_map(struct perf_probe_event * pev,struct probe_trace_event ** tevs)3045 static int find_probe_trace_events_from_map(struct perf_probe_event *pev,
3046 struct probe_trace_event **tevs)
3047 {
3048 struct map *map = NULL;
3049 struct ref_reloc_sym *reloc_sym = NULL;
3050 struct symbol *sym;
3051 struct symbol **syms = NULL;
3052 struct probe_trace_event *tev;
3053 struct perf_probe_point *pp = &pev->point;
3054 struct probe_trace_point *tp;
3055 int num_matched_functions;
3056 int ret, i, j, skipped = 0;
3057 char *mod_name;
3058
3059 map = get_target_map(pev->target, pev->nsi, pev->uprobes);
3060 if (!map) {
3061 ret = -EINVAL;
3062 goto out;
3063 }
3064
3065 syms = malloc(sizeof(struct symbol *) * probe_conf.max_probes);
3066 if (!syms) {
3067 ret = -ENOMEM;
3068 goto out;
3069 }
3070
3071 /*
3072 * Load matched symbols: Since the different local symbols may have
3073 * same name but different addresses, this lists all the symbols.
3074 */
3075 num_matched_functions = find_probe_functions(map, pp->function, syms);
3076 if (num_matched_functions <= 0) {
3077 if (num_matched_functions == -EACCES) {
3078 pr_err("Failed to load symbols from %s\n",
3079 pev->target ?: "/proc/kallsyms");
3080 if (pev->target)
3081 pr_err("Please ensure the file is not stripped.\n");
3082 else
3083 pr_kallsyms_access_error();
3084 } else
3085 pr_err("Failed to find symbol %s in %s\n", pp->function,
3086 pev->target ? : "kernel");
3087 ret = -ENOENT;
3088 goto out;
3089 } else if (num_matched_functions > probe_conf.max_probes) {
3090 pr_err("Too many functions matched in %s\n",
3091 pev->target ? : "kernel");
3092 ret = -E2BIG;
3093 goto out;
3094 }
3095
3096 /* Note that the symbols in the kmodule are not relocated */
3097 if (!pev->uprobes && !pev->target &&
3098 (!pp->retprobe || kretprobe_offset_is_supported())) {
3099 reloc_sym = kernel_get_ref_reloc_sym(NULL);
3100 if (!reloc_sym) {
3101 pr_warning("Relocated base symbol is not found! "
3102 "Check /proc/sys/kernel/kptr_restrict\n"
3103 "and /proc/sys/kernel/perf_event_paranoid. "
3104 "Or run as privileged perf user.\n\n");
3105 ret = -EINVAL;
3106 goto out;
3107 }
3108 }
3109
3110 /* Setup result trace-probe-events */
3111 *tevs = zalloc(sizeof(*tev) * num_matched_functions);
3112 if (!*tevs) {
3113 ret = -ENOMEM;
3114 goto out;
3115 }
3116
3117 ret = 0;
3118
3119 for (j = 0; j < num_matched_functions; j++) {
3120 sym = syms[j];
3121
3122 if (sym->type != STT_FUNC)
3123 continue;
3124
3125 /* There can be duplicated symbols in the map */
3126 for (i = 0; i < j; i++)
3127 if (sym->start == syms[i]->start) {
3128 pr_debug("Found duplicated symbol %s @ %" PRIx64 "\n",
3129 sym->name, sym->start);
3130 break;
3131 }
3132 if (i != j)
3133 continue;
3134
3135 tev = (*tevs) + ret;
3136 tp = &tev->point;
3137 if (ret == num_matched_functions) {
3138 pr_warning("Too many symbols are listed. Skip it.\n");
3139 break;
3140 }
3141 ret++;
3142
3143 if (pp->offset > sym->end - sym->start) {
3144 pr_warning("Offset %ld is bigger than the size of %s\n",
3145 pp->offset, sym->name);
3146 ret = -ENOENT;
3147 goto err_out;
3148 }
3149 /* Add one probe point */
3150 tp->address = map__unmap_ip(map, sym->start) + pp->offset;
3151
3152 /* Check the kprobe (not in module) is within .text */
3153 if (!pev->uprobes && !pev->target &&
3154 kprobe_warn_out_range(sym->name, tp->address)) {
3155 tp->symbol = NULL; /* Skip it */
3156 skipped++;
3157 } else if (reloc_sym) {
3158 tp->symbol = strdup_or_goto(reloc_sym->name, nomem_out);
3159 tp->offset = tp->address - reloc_sym->addr;
3160 } else {
3161 tp->symbol = strdup_or_goto(sym->name, nomem_out);
3162 tp->offset = pp->offset;
3163 }
3164 tp->realname = strdup_or_goto(sym->name, nomem_out);
3165
3166 tp->retprobe = pp->retprobe;
3167 if (pev->target) {
3168 if (pev->uprobes) {
3169 tev->point.module = strdup_or_goto(pev->target,
3170 nomem_out);
3171 } else {
3172 mod_name = find_module_name(pev->target);
3173 tev->point.module =
3174 strdup(mod_name ? mod_name : pev->target);
3175 free(mod_name);
3176 if (!tev->point.module)
3177 goto nomem_out;
3178 }
3179 }
3180 tev->uprobes = pev->uprobes;
3181 tev->nargs = pev->nargs;
3182 if (tev->nargs) {
3183 tev->args = zalloc(sizeof(struct probe_trace_arg) *
3184 tev->nargs);
3185 if (tev->args == NULL)
3186 goto nomem_out;
3187 }
3188 for (i = 0; i < tev->nargs; i++) {
3189 if (pev->args[i].name)
3190 tev->args[i].name =
3191 strdup_or_goto(pev->args[i].name,
3192 nomem_out);
3193
3194 tev->args[i].value = strdup_or_goto(pev->args[i].var,
3195 nomem_out);
3196 if (pev->args[i].type)
3197 tev->args[i].type =
3198 strdup_or_goto(pev->args[i].type,
3199 nomem_out);
3200 }
3201 arch__fix_tev_from_maps(pev, tev, map, sym);
3202 }
3203 if (ret == skipped) {
3204 ret = -ENOENT;
3205 goto err_out;
3206 }
3207
3208 out:
3209 map__put(map);
3210 free(syms);
3211 return ret;
3212
3213 nomem_out:
3214 ret = -ENOMEM;
3215 err_out:
3216 clear_probe_trace_events(*tevs, num_matched_functions);
3217 zfree(tevs);
3218 goto out;
3219 }
3220
try_to_find_absolute_address(struct perf_probe_event * pev,struct probe_trace_event ** tevs)3221 static int try_to_find_absolute_address(struct perf_probe_event *pev,
3222 struct probe_trace_event **tevs)
3223 {
3224 struct perf_probe_point *pp = &pev->point;
3225 struct probe_trace_event *tev;
3226 struct probe_trace_point *tp;
3227 int i, err;
3228
3229 if (!(pev->point.function && !strncmp(pev->point.function, "0x", 2)))
3230 return -EINVAL;
3231 if (perf_probe_event_need_dwarf(pev))
3232 return -EINVAL;
3233
3234 /*
3235 * This is 'perf probe /lib/libc.so 0xabcd'. Try to probe at
3236 * absolute address.
3237 *
3238 * Only one tev can be generated by this.
3239 */
3240 *tevs = zalloc(sizeof(*tev));
3241 if (!*tevs)
3242 return -ENOMEM;
3243
3244 tev = *tevs;
3245 tp = &tev->point;
3246
3247 /*
3248 * Don't use tp->offset, use address directly, because
3249 * in synthesize_probe_trace_command() address cannot be
3250 * zero.
3251 */
3252 tp->address = pev->point.abs_address;
3253 tp->retprobe = pp->retprobe;
3254 tev->uprobes = pev->uprobes;
3255
3256 err = -ENOMEM;
3257 /*
3258 * Give it a '0x' leading symbol name.
3259 * In __add_probe_trace_events, a NULL symbol is interpreted as
3260 * invalid.
3261 */
3262 if (asprintf(&tp->symbol, "0x%" PRIx64, tp->address) < 0)
3263 goto errout;
3264
3265 /* For kprobe, check range */
3266 if ((!tev->uprobes) &&
3267 (kprobe_warn_out_range(tev->point.symbol,
3268 tev->point.address))) {
3269 err = -EACCES;
3270 goto errout;
3271 }
3272
3273 if (asprintf(&tp->realname, "abs_%" PRIx64, tp->address) < 0)
3274 goto errout;
3275
3276 if (pev->target) {
3277 tp->module = strdup(pev->target);
3278 if (!tp->module)
3279 goto errout;
3280 }
3281
3282 if (tev->group) {
3283 tev->group = strdup(pev->group);
3284 if (!tev->group)
3285 goto errout;
3286 }
3287
3288 if (pev->event) {
3289 tev->event = strdup(pev->event);
3290 if (!tev->event)
3291 goto errout;
3292 }
3293
3294 tev->nargs = pev->nargs;
3295 tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
3296 if (!tev->args)
3297 goto errout;
3298
3299 for (i = 0; i < tev->nargs; i++)
3300 copy_to_probe_trace_arg(&tev->args[i], &pev->args[i]);
3301
3302 return 1;
3303
3304 errout:
3305 clear_probe_trace_events(*tevs, 1);
3306 *tevs = NULL;
3307 return err;
3308 }
3309
3310 /* Concatenate two arrays */
memcat(void * a,size_t sz_a,void * b,size_t sz_b)3311 static void *memcat(void *a, size_t sz_a, void *b, size_t sz_b)
3312 {
3313 void *ret;
3314
3315 ret = malloc(sz_a + sz_b);
3316 if (ret) {
3317 memcpy(ret, a, sz_a);
3318 memcpy(ret + sz_a, b, sz_b);
3319 }
3320 return ret;
3321 }
3322
3323 static int
concat_probe_trace_events(struct probe_trace_event ** tevs,int * ntevs,struct probe_trace_event ** tevs2,int ntevs2)3324 concat_probe_trace_events(struct probe_trace_event **tevs, int *ntevs,
3325 struct probe_trace_event **tevs2, int ntevs2)
3326 {
3327 struct probe_trace_event *new_tevs;
3328 int ret = 0;
3329
3330 if (*ntevs == 0) {
3331 *tevs = *tevs2;
3332 *ntevs = ntevs2;
3333 *tevs2 = NULL;
3334 return 0;
3335 }
3336
3337 if (*ntevs + ntevs2 > probe_conf.max_probes)
3338 ret = -E2BIG;
3339 else {
3340 /* Concatenate the array of probe_trace_event */
3341 new_tevs = memcat(*tevs, (*ntevs) * sizeof(**tevs),
3342 *tevs2, ntevs2 * sizeof(**tevs2));
3343 if (!new_tevs)
3344 ret = -ENOMEM;
3345 else {
3346 free(*tevs);
3347 *tevs = new_tevs;
3348 *ntevs += ntevs2;
3349 }
3350 }
3351 if (ret < 0)
3352 clear_probe_trace_events(*tevs2, ntevs2);
3353 zfree(tevs2);
3354
3355 return ret;
3356 }
3357
3358 /*
3359 * Try to find probe_trace_event from given probe caches. Return the number
3360 * of cached events found, if an error occurs return the error.
3361 */
find_cached_events(struct perf_probe_event * pev,struct probe_trace_event ** tevs,const char * target)3362 static int find_cached_events(struct perf_probe_event *pev,
3363 struct probe_trace_event **tevs,
3364 const char *target)
3365 {
3366 struct probe_cache *cache;
3367 struct probe_cache_entry *entry;
3368 struct probe_trace_event *tmp_tevs = NULL;
3369 int ntevs = 0;
3370 int ret = 0;
3371
3372 cache = probe_cache__new(target, pev->nsi);
3373 /* Return 0 ("not found") if the target has no probe cache. */
3374 if (!cache)
3375 return 0;
3376
3377 for_each_probe_cache_entry(entry, cache) {
3378 /* Skip the cache entry which has no name */
3379 if (!entry->pev.event || !entry->pev.group)
3380 continue;
3381 if ((!pev->group || strglobmatch(entry->pev.group, pev->group)) &&
3382 strglobmatch(entry->pev.event, pev->event)) {
3383 ret = probe_cache_entry__get_event(entry, &tmp_tevs);
3384 if (ret > 0)
3385 ret = concat_probe_trace_events(tevs, &ntevs,
3386 &tmp_tevs, ret);
3387 if (ret < 0)
3388 break;
3389 }
3390 }
3391 probe_cache__delete(cache);
3392 if (ret < 0) {
3393 clear_probe_trace_events(*tevs, ntevs);
3394 zfree(tevs);
3395 } else {
3396 ret = ntevs;
3397 if (ntevs > 0 && target && target[0] == '/')
3398 pev->uprobes = true;
3399 }
3400
3401 return ret;
3402 }
3403
3404 /* Try to find probe_trace_event from all probe caches */
find_cached_events_all(struct perf_probe_event * pev,struct probe_trace_event ** tevs)3405 static int find_cached_events_all(struct perf_probe_event *pev,
3406 struct probe_trace_event **tevs)
3407 {
3408 struct probe_trace_event *tmp_tevs = NULL;
3409 struct strlist *bidlist;
3410 struct str_node *nd;
3411 char *pathname;
3412 int ntevs = 0;
3413 int ret;
3414
3415 /* Get the buildid list of all valid caches */
3416 bidlist = build_id_cache__list_all(true);
3417 if (!bidlist) {
3418 ret = -errno;
3419 pr_debug("Failed to get buildids: %d\n", ret);
3420 return ret;
3421 }
3422
3423 ret = 0;
3424 strlist__for_each_entry(nd, bidlist) {
3425 pathname = build_id_cache__origname(nd->s);
3426 ret = find_cached_events(pev, &tmp_tevs, pathname);
3427 /* In the case of cnt == 0, we just skip it */
3428 if (ret > 0)
3429 ret = concat_probe_trace_events(tevs, &ntevs,
3430 &tmp_tevs, ret);
3431 free(pathname);
3432 if (ret < 0)
3433 break;
3434 }
3435 strlist__delete(bidlist);
3436
3437 if (ret < 0) {
3438 clear_probe_trace_events(*tevs, ntevs);
3439 zfree(tevs);
3440 } else
3441 ret = ntevs;
3442
3443 return ret;
3444 }
3445
find_probe_trace_events_from_cache(struct perf_probe_event * pev,struct probe_trace_event ** tevs)3446 static int find_probe_trace_events_from_cache(struct perf_probe_event *pev,
3447 struct probe_trace_event **tevs)
3448 {
3449 struct probe_cache *cache;
3450 struct probe_cache_entry *entry;
3451 struct probe_trace_event *tev;
3452 struct str_node *node;
3453 int ret, i;
3454
3455 if (pev->sdt) {
3456 /* For SDT/cached events, we use special search functions */
3457 if (!pev->target)
3458 return find_cached_events_all(pev, tevs);
3459 else
3460 return find_cached_events(pev, tevs, pev->target);
3461 }
3462 cache = probe_cache__new(pev->target, pev->nsi);
3463 if (!cache)
3464 return 0;
3465
3466 entry = probe_cache__find(cache, pev);
3467 if (!entry) {
3468 /* SDT must be in the cache */
3469 ret = pev->sdt ? -ENOENT : 0;
3470 goto out;
3471 }
3472
3473 ret = strlist__nr_entries(entry->tevlist);
3474 if (ret > probe_conf.max_probes) {
3475 pr_debug("Too many entries matched in the cache of %s\n",
3476 pev->target ? : "kernel");
3477 ret = -E2BIG;
3478 goto out;
3479 }
3480
3481 *tevs = zalloc(ret * sizeof(*tev));
3482 if (!*tevs) {
3483 ret = -ENOMEM;
3484 goto out;
3485 }
3486
3487 i = 0;
3488 strlist__for_each_entry(node, entry->tevlist) {
3489 tev = &(*tevs)[i++];
3490 ret = parse_probe_trace_command(node->s, tev);
3491 if (ret < 0)
3492 goto out;
3493 /* Set the uprobes attribute as same as original */
3494 tev->uprobes = pev->uprobes;
3495 }
3496 ret = i;
3497
3498 out:
3499 probe_cache__delete(cache);
3500 return ret;
3501 }
3502
convert_to_probe_trace_events(struct perf_probe_event * pev,struct probe_trace_event ** tevs)3503 static int convert_to_probe_trace_events(struct perf_probe_event *pev,
3504 struct probe_trace_event **tevs)
3505 {
3506 int ret;
3507
3508 if (!pev->group && !pev->sdt) {
3509 /* Set group name if not given */
3510 if (!pev->uprobes) {
3511 pev->group = strdup(PERFPROBE_GROUP);
3512 ret = pev->group ? 0 : -ENOMEM;
3513 } else
3514 ret = convert_exec_to_group(pev->target, &pev->group);
3515 if (ret != 0) {
3516 pr_warning("Failed to make a group name.\n");
3517 return ret;
3518 }
3519 }
3520
3521 ret = try_to_find_absolute_address(pev, tevs);
3522 if (ret > 0)
3523 return ret;
3524
3525 /* At first, we need to lookup cache entry */
3526 ret = find_probe_trace_events_from_cache(pev, tevs);
3527 if (ret > 0 || pev->sdt) /* SDT can be found only in the cache */
3528 return ret == 0 ? -ENOENT : ret; /* Found in probe cache */
3529
3530 /* Convert perf_probe_event with debuginfo */
3531 ret = try_to_find_probe_trace_events(pev, tevs);
3532 if (ret != 0)
3533 return ret; /* Found in debuginfo or got an error */
3534
3535 return find_probe_trace_events_from_map(pev, tevs);
3536 }
3537
convert_perf_probe_events(struct perf_probe_event * pevs,int npevs)3538 int convert_perf_probe_events(struct perf_probe_event *pevs, int npevs)
3539 {
3540 int i, ret;
3541
3542 /* Loop 1: convert all events */
3543 for (i = 0; i < npevs; i++) {
3544 /* Init kprobe blacklist if needed */
3545 if (!pevs[i].uprobes)
3546 kprobe_blacklist__init();
3547 /* Convert with or without debuginfo */
3548 ret = convert_to_probe_trace_events(&pevs[i], &pevs[i].tevs);
3549 if (ret < 0)
3550 return ret;
3551 pevs[i].ntevs = ret;
3552 }
3553 /* This just release blacklist only if allocated */
3554 kprobe_blacklist__release();
3555
3556 return 0;
3557 }
3558
show_probe_trace_event(struct probe_trace_event * tev)3559 static int show_probe_trace_event(struct probe_trace_event *tev)
3560 {
3561 char *buf = synthesize_probe_trace_command(tev);
3562
3563 if (!buf) {
3564 pr_debug("Failed to synthesize probe trace event.\n");
3565 return -EINVAL;
3566 }
3567
3568 /* Showing definition always go stdout */
3569 printf("%s\n", buf);
3570 free(buf);
3571
3572 return 0;
3573 }
3574
show_probe_trace_events(struct perf_probe_event * pevs,int npevs)3575 int show_probe_trace_events(struct perf_probe_event *pevs, int npevs)
3576 {
3577 struct strlist *namelist = strlist__new(NULL, NULL);
3578 struct probe_trace_event *tev;
3579 struct perf_probe_event *pev;
3580 int i, j, ret = 0;
3581
3582 if (!namelist)
3583 return -ENOMEM;
3584
3585 for (j = 0; j < npevs && !ret; j++) {
3586 pev = &pevs[j];
3587 for (i = 0; i < pev->ntevs && !ret; i++) {
3588 tev = &pev->tevs[i];
3589 /* Skip if the symbol is out of .text or blacklisted */
3590 if (!tev->point.symbol && !pev->uprobes)
3591 continue;
3592
3593 /* Set new name for tev (and update namelist) */
3594 ret = probe_trace_event__set_name(tev, pev,
3595 namelist, true);
3596 if (!ret)
3597 ret = show_probe_trace_event(tev);
3598 }
3599 }
3600 strlist__delete(namelist);
3601
3602 return ret;
3603 }
3604
show_bootconfig_event(struct probe_trace_event * tev)3605 static int show_bootconfig_event(struct probe_trace_event *tev)
3606 {
3607 struct probe_trace_point *tp = &tev->point;
3608 struct strbuf buf;
3609 char *ret = NULL;
3610 int err;
3611
3612 if (strbuf_init(&buf, 32) < 0)
3613 return -ENOMEM;
3614
3615 err = synthesize_kprobe_trace_def(tp, &buf);
3616 if (err >= 0)
3617 err = synthesize_probe_trace_args(tev, &buf);
3618 if (err >= 0)
3619 ret = strbuf_detach(&buf, NULL);
3620 strbuf_release(&buf);
3621
3622 if (ret) {
3623 printf("'%s'", ret);
3624 free(ret);
3625 }
3626
3627 return err;
3628 }
3629
show_bootconfig_events(struct perf_probe_event * pevs,int npevs)3630 int show_bootconfig_events(struct perf_probe_event *pevs, int npevs)
3631 {
3632 struct strlist *namelist = strlist__new(NULL, NULL);
3633 struct probe_trace_event *tev;
3634 struct perf_probe_event *pev;
3635 char *cur_name = NULL;
3636 int i, j, ret = 0;
3637
3638 if (!namelist)
3639 return -ENOMEM;
3640
3641 for (j = 0; j < npevs && !ret; j++) {
3642 pev = &pevs[j];
3643 if (pev->group && strcmp(pev->group, "probe"))
3644 pr_warning("WARN: Group name %s is ignored\n", pev->group);
3645 if (pev->uprobes) {
3646 pr_warning("ERROR: Bootconfig doesn't support uprobes\n");
3647 ret = -EINVAL;
3648 break;
3649 }
3650 for (i = 0; i < pev->ntevs && !ret; i++) {
3651 tev = &pev->tevs[i];
3652 /* Skip if the symbol is out of .text or blacklisted */
3653 if (!tev->point.symbol && !pev->uprobes)
3654 continue;
3655
3656 /* Set new name for tev (and update namelist) */
3657 ret = probe_trace_event__set_name(tev, pev,
3658 namelist, true);
3659 if (ret)
3660 break;
3661
3662 if (!cur_name || strcmp(cur_name, tev->event)) {
3663 printf("%sftrace.event.kprobes.%s.probe = ",
3664 cur_name ? "\n" : "", tev->event);
3665 cur_name = tev->event;
3666 } else
3667 printf(", ");
3668 ret = show_bootconfig_event(tev);
3669 }
3670 }
3671 printf("\n");
3672 strlist__delete(namelist);
3673
3674 return ret;
3675 }
3676
apply_perf_probe_events(struct perf_probe_event * pevs,int npevs)3677 int apply_perf_probe_events(struct perf_probe_event *pevs, int npevs)
3678 {
3679 int i, ret = 0;
3680
3681 /* Loop 2: add all events */
3682 for (i = 0; i < npevs; i++) {
3683 ret = __add_probe_trace_events(&pevs[i], pevs[i].tevs,
3684 pevs[i].ntevs,
3685 probe_conf.force_add);
3686 if (ret < 0)
3687 break;
3688 }
3689 return ret;
3690 }
3691
cleanup_perf_probe_events(struct perf_probe_event * pevs,int npevs)3692 void cleanup_perf_probe_events(struct perf_probe_event *pevs, int npevs)
3693 {
3694 int i, j;
3695 struct perf_probe_event *pev;
3696
3697 /* Loop 3: cleanup and free trace events */
3698 for (i = 0; i < npevs; i++) {
3699 pev = &pevs[i];
3700 for (j = 0; j < pevs[i].ntevs; j++)
3701 clear_probe_trace_event(&pevs[i].tevs[j]);
3702 zfree(&pevs[i].tevs);
3703 pevs[i].ntevs = 0;
3704 nsinfo__zput(pev->nsi);
3705 clear_perf_probe_event(&pevs[i]);
3706 }
3707 }
3708
add_perf_probe_events(struct perf_probe_event * pevs,int npevs)3709 int add_perf_probe_events(struct perf_probe_event *pevs, int npevs)
3710 {
3711 int ret;
3712
3713 ret = init_probe_symbol_maps(pevs->uprobes);
3714 if (ret < 0)
3715 return ret;
3716
3717 ret = convert_perf_probe_events(pevs, npevs);
3718 if (ret == 0)
3719 ret = apply_perf_probe_events(pevs, npevs);
3720
3721 cleanup_perf_probe_events(pevs, npevs);
3722
3723 exit_probe_symbol_maps();
3724 return ret;
3725 }
3726
del_perf_probe_events(struct strfilter * filter)3727 int del_perf_probe_events(struct strfilter *filter)
3728 {
3729 int ret, ret2, ufd = -1, kfd = -1;
3730 char *str = strfilter__string(filter);
3731
3732 if (!str)
3733 return -EINVAL;
3734
3735 /* Get current event names */
3736 ret = probe_file__open_both(&kfd, &ufd, PF_FL_RW);
3737 if (ret < 0)
3738 goto out;
3739
3740 ret = probe_file__del_events(kfd, filter);
3741 if (ret < 0 && ret != -ENOENT)
3742 goto error;
3743
3744 ret2 = probe_file__del_events(ufd, filter);
3745 if (ret2 < 0 && ret2 != -ENOENT) {
3746 ret = ret2;
3747 goto error;
3748 }
3749 ret = 0;
3750
3751 error:
3752 if (kfd >= 0)
3753 close(kfd);
3754 if (ufd >= 0)
3755 close(ufd);
3756 out:
3757 free(str);
3758
3759 return ret;
3760 }
3761
show_available_funcs(const char * target,struct nsinfo * nsi,struct strfilter * _filter,bool user)3762 int show_available_funcs(const char *target, struct nsinfo *nsi,
3763 struct strfilter *_filter, bool user)
3764 {
3765 struct map *map;
3766 struct dso *dso;
3767 int ret;
3768
3769 ret = init_probe_symbol_maps(user);
3770 if (ret < 0)
3771 return ret;
3772
3773 /* Get a symbol map */
3774 map = get_target_map(target, nsi, user);
3775 if (!map) {
3776 pr_err("Failed to get a map for %s\n", (target) ? : "kernel");
3777 return -EINVAL;
3778 }
3779
3780 ret = map__load(map);
3781 if (ret) {
3782 if (ret == -2) {
3783 char *str = strfilter__string(_filter);
3784 pr_err("Failed to find symbols matched to \"%s\"\n",
3785 str);
3786 free(str);
3787 } else
3788 pr_err("Failed to load symbols in %s\n",
3789 (target) ? : "kernel");
3790 goto end;
3791 }
3792 dso = map__dso(map);
3793 dso__sort_by_name(dso);
3794
3795 /* Show all (filtered) symbols */
3796 setup_pager();
3797
3798 for (size_t i = 0; i < dso->symbol_names_len; i++) {
3799 struct symbol *pos = dso->symbol_names[i];
3800
3801 if (strfilter__compare(_filter, pos->name))
3802 printf("%s\n", pos->name);
3803 }
3804 end:
3805 map__put(map);
3806 exit_probe_symbol_maps();
3807
3808 return ret;
3809 }
3810
copy_to_probe_trace_arg(struct probe_trace_arg * tvar,struct perf_probe_arg * pvar)3811 int copy_to_probe_trace_arg(struct probe_trace_arg *tvar,
3812 struct perf_probe_arg *pvar)
3813 {
3814 tvar->value = strdup(pvar->var);
3815 if (tvar->value == NULL)
3816 return -ENOMEM;
3817 if (pvar->type) {
3818 tvar->type = strdup(pvar->type);
3819 if (tvar->type == NULL)
3820 return -ENOMEM;
3821 }
3822 if (pvar->name) {
3823 tvar->name = strdup(pvar->name);
3824 if (tvar->name == NULL)
3825 return -ENOMEM;
3826 } else
3827 tvar->name = NULL;
3828 return 0;
3829 }
3830