xref: /linux/tools/perf/util/probe-event.c (revision e3b2949e3fa2fd8c19cd5fbb0424d38f70a70e9c)
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 <libgen.h>
15 #include <stdio.h>
16 #include <unistd.h>
17 #include <stdlib.h>
18 #include <string.h>
19 #include <stdarg.h>
20 #include <limits.h>
21 #include <elf.h>
22 
23 #include "build-id.h"
24 #include "event.h"
25 #include "namespaces.h"
26 #include "strlist.h"
27 #include "strfilter.h"
28 #include "debug.h"
29 #include "dso.h"
30 #include "color.h"
31 #include "map.h"
32 #include "maps.h"
33 #include "mutex.h"
34 #include "symbol.h"
35 #include <api/fs/fs.h>
36 #include "trace-event.h"	/* For __maybe_unused */
37 #include "probe-event.h"
38 #include "probe-finder.h"
39 #include "probe-file.h"
40 #include "session.h"
41 #include "string2.h"
42 #include "strbuf.h"
43 
44 #include <subcmd/pager.h>
45 #include <linux/ctype.h>
46 #include <linux/zalloc.h>
47 
48 #ifdef HAVE_DEBUGINFOD_SUPPORT
49 #include <elfutils/debuginfod.h>
50 #endif
51 
52 #define PERFPROBE_GROUP "probe"
53 
54 /* Defined in kernel/trace/trace.h */
55 #define MAX_EVENT_NAME_LEN	64
56 
57 bool probe_event_dry_run;	/* Dry run flag */
58 struct probe_conf probe_conf = { .magic_num = DEFAULT_PROBE_MAGIC_NUM };
59 
60 static char *synthesize_perf_probe_point(struct perf_probe_point *pp);
61 
62 #define semantic_error(msg ...) pr_err("Semantic error :" msg)
63 
64 int e_snprintf(char *str, size_t size, const char *format, ...)
65 {
66 	int ret;
67 	va_list ap;
68 	va_start(ap, format);
69 	ret = vsnprintf(str, size, format, ap);
70 	va_end(ap);
71 	if (ret >= (int)size)
72 		ret = -E2BIG;
73 	return ret;
74 }
75 
76 static struct machine *host_machine;
77 
78 /* Initialize symbol maps and path of vmlinux/modules */
79 int init_probe_symbol_maps(bool user_only)
80 {
81 	int ret;
82 
83 	symbol_conf.allow_aliases = true;
84 	ret = symbol__init(NULL);
85 	if (ret < 0) {
86 		pr_debug("Failed to init symbol map.\n");
87 		goto out;
88 	}
89 
90 	if (host_machine || user_only)	/* already initialized */
91 		return 0;
92 
93 	if (symbol_conf.vmlinux_name)
94 		pr_debug("Use vmlinux: %s\n", symbol_conf.vmlinux_name);
95 
96 	host_machine = machine__new_host();
97 	if (!host_machine) {
98 		pr_debug("machine__new_host() failed.\n");
99 		symbol__exit();
100 		ret = -1;
101 	}
102 out:
103 	if (ret < 0)
104 		pr_warning("Failed to init vmlinux path.\n");
105 	return ret;
106 }
107 
108 void exit_probe_symbol_maps(void)
109 {
110 	machine__delete(host_machine);
111 	host_machine = NULL;
112 	symbol__exit();
113 }
114 
115 static struct ref_reloc_sym *kernel_get_ref_reloc_sym(struct map **pmap)
116 {
117 	struct kmap *kmap;
118 	struct map *map = machine__kernel_map(host_machine);
119 
120 	if (map__load(map) < 0)
121 		return NULL;
122 
123 	kmap = map__kmap(map);
124 	if (!kmap)
125 		return NULL;
126 
127 	if (pmap)
128 		*pmap = map;
129 
130 	return kmap->ref_reloc_sym;
131 }
132 
133 static int kernel_get_symbol_address_by_name(const char *name, u64 *addr,
134 					     bool reloc, bool reladdr)
135 {
136 	struct ref_reloc_sym *reloc_sym;
137 	struct symbol *sym;
138 	struct map *map;
139 
140 	/* ref_reloc_sym is just a label. Need a special fix*/
141 	reloc_sym = kernel_get_ref_reloc_sym(&map);
142 	if (reloc_sym && strcmp(name, reloc_sym->name) == 0)
143 		*addr = (!map__reloc(map) || reloc) ? reloc_sym->addr :
144 			reloc_sym->unrelocated_addr;
145 	else {
146 		sym = machine__find_kernel_symbol_by_name(host_machine, name, &map);
147 		if (!sym)
148 			return -ENOENT;
149 		*addr = map__unmap_ip(map, sym->start) -
150 			((reloc) ? 0 : map__reloc(map)) -
151 			((reladdr) ? map__start(map) : 0);
152 	}
153 	return 0;
154 }
155 
156 struct kernel_get_module_map_cb_args {
157 	const char *module;
158 	struct map *result;
159 };
160 
161 static int kernel_get_module_map_cb(struct map *map, void *data)
162 {
163 	struct kernel_get_module_map_cb_args *args = data;
164 	struct dso *dso = map__dso(map);
165 	const char *short_name = dso__short_name(dso);
166 	u16 short_name_len =  dso__short_name_len(dso);
167 
168 	if (strncmp(short_name + 1, args->module, short_name_len - 2) == 0 &&
169 	    args->module[short_name_len - 2] == '\0') {
170 		args->result = map__get(map);
171 		return 1;
172 	}
173 	return 0;
174 }
175 
176 static struct map *kernel_get_module_map(const char *module)
177 {
178 	struct kernel_get_module_map_cb_args args = {
179 		.module = module,
180 		.result = NULL,
181 	};
182 
183 	/* A file path -- this is an offline module */
184 	if (module && strchr(module, '/'))
185 		return dso__new_map(module);
186 
187 	if (!module) {
188 		struct map *map = machine__kernel_map(host_machine);
189 
190 		return map__get(map);
191 	}
192 
193 	maps__for_each_map(machine__kernel_maps(host_machine), kernel_get_module_map_cb, &args);
194 
195 	return args.result;
196 }
197 
198 struct map *get_target_map(const char *target, struct nsinfo *nsi, bool user)
199 {
200 	/* Init maps of given executable or kernel */
201 	if (user) {
202 		struct map *map;
203 		struct dso *dso;
204 
205 		map = dso__new_map(target);
206 		dso = map ? map__dso(map) : NULL;
207 		if (dso) {
208 			mutex_lock(dso__lock(dso));
209 			dso__set_nsinfo(dso, nsinfo__get(nsi));
210 			mutex_unlock(dso__lock(dso));
211 		}
212 		return map;
213 	} else {
214 		return kernel_get_module_map(target);
215 	}
216 }
217 
218 static int convert_exec_to_group(const char *exec, char **result)
219 {
220 	char *ptr1, *ptr2, *exec_copy;
221 	char buf[64];
222 	int ret;
223 
224 	exec_copy = strdup(exec);
225 	if (!exec_copy)
226 		return -ENOMEM;
227 
228 	ptr1 = basename(exec_copy);
229 	if (!ptr1) {
230 		ret = -EINVAL;
231 		goto out;
232 	}
233 
234 	for (ptr2 = ptr1; *ptr2 != '\0'; ptr2++) {
235 		if (!isalnum(*ptr2) && *ptr2 != '_') {
236 			*ptr2 = '\0';
237 			break;
238 		}
239 	}
240 
241 	ret = e_snprintf(buf, sizeof(buf), "%s_%s", PERFPROBE_GROUP, ptr1);
242 	if (ret < 0)
243 		goto out;
244 
245 	*result = strdup(buf);
246 	ret = *result ? 0 : -ENOMEM;
247 
248 out:
249 	free(exec_copy);
250 	return ret;
251 }
252 
253 static void clear_perf_probe_point(struct perf_probe_point *pp)
254 {
255 	zfree(&pp->file);
256 	zfree(&pp->function);
257 	zfree(&pp->lazy_line);
258 }
259 
260 static void clear_probe_trace_events(struct probe_trace_event *tevs, int ntevs)
261 {
262 	int i;
263 
264 	for (i = 0; i < ntevs; i++)
265 		clear_probe_trace_event(tevs + i);
266 }
267 
268 static bool kprobe_blacklist__listed(u64 address);
269 static bool kprobe_warn_out_range(const char *symbol, u64 address)
270 {
271 	struct map *map;
272 	bool ret = false;
273 
274 	map = kernel_get_module_map(NULL);
275 	if (map) {
276 		ret = address <= map__start(map) || map__end(map) < address;
277 		if (ret)
278 			pr_warning("%s is out of .text, skip it.\n", symbol);
279 		map__put(map);
280 	}
281 	if (!ret && kprobe_blacklist__listed(address)) {
282 		pr_warning("%s is blacklisted function, skip it.\n", symbol);
283 		ret = true;
284 	}
285 
286 	return ret;
287 }
288 
289 /*
290  * @module can be module name of module file path. In case of path,
291  * inspect elf and find out what is actual module name.
292  * Caller has to free mod_name after using it.
293  */
294 static char *find_module_name(const char *module)
295 {
296 	int fd;
297 	Elf *elf;
298 	GElf_Ehdr ehdr;
299 	GElf_Shdr shdr;
300 	Elf_Data *data;
301 	Elf_Scn *sec;
302 	char *mod_name = NULL;
303 	int name_offset;
304 
305 	fd = open(module, O_RDONLY);
306 	if (fd < 0)
307 		return NULL;
308 
309 	elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
310 	if (elf == NULL)
311 		goto elf_err;
312 
313 	if (gelf_getehdr(elf, &ehdr) == NULL)
314 		goto ret_err;
315 
316 	sec = elf_section_by_name(elf, &ehdr, &shdr,
317 			".gnu.linkonce.this_module", NULL);
318 	if (!sec)
319 		goto ret_err;
320 
321 	data = elf_getdata(sec, NULL);
322 	if (!data || !data->d_buf)
323 		goto ret_err;
324 
325 	/*
326 	 * NOTE:
327 	 * '.gnu.linkonce.this_module' section of kernel module elf directly
328 	 * maps to 'struct module' from linux/module.h. This section contains
329 	 * actual module name which will be used by kernel after loading it.
330 	 * But, we cannot use 'struct module' here since linux/module.h is not
331 	 * exposed to user-space. Offset of 'name' has remained same from long
332 	 * time, so hardcoding it here.
333 	 */
334 	if (ehdr.e_ident[EI_CLASS] == ELFCLASS32)
335 		name_offset = 12;
336 	else	/* expect ELFCLASS64 by default */
337 		name_offset = 24;
338 
339 	mod_name = strdup((char *)data->d_buf + name_offset);
340 
341 ret_err:
342 	elf_end(elf);
343 elf_err:
344 	close(fd);
345 	return mod_name;
346 }
347 
348 #ifdef HAVE_LIBDW_SUPPORT
349 
350 static int kernel_get_module_dso(const char *module, struct dso **pdso)
351 {
352 	struct dso *dso;
353 	struct map *map;
354 	const char *vmlinux_name;
355 	int ret = 0;
356 
357 	if (module) {
358 		char module_name[128];
359 
360 		snprintf(module_name, sizeof(module_name), "[%s]", module);
361 		map = maps__find_by_name(machine__kernel_maps(host_machine), module_name);
362 		if (map) {
363 			dso = map__dso(map);
364 			map__put(map);
365 			goto found;
366 		}
367 		pr_debug("Failed to find module %s.\n", module);
368 		return -ENOENT;
369 	}
370 
371 	map = machine__kernel_map(host_machine);
372 	dso = map__dso(map);
373 	if (!dso__has_build_id(dso))
374 		dso__read_running_kernel_build_id(dso, host_machine);
375 
376 	vmlinux_name = symbol_conf.vmlinux_name;
377 	*dso__load_errno(dso) = 0;
378 	if (vmlinux_name)
379 		ret = dso__load_vmlinux(dso, map, vmlinux_name, false);
380 	else
381 		ret = dso__load_vmlinux_path(dso, map);
382 found:
383 	*pdso = dso;
384 	return ret;
385 }
386 
387 /*
388  * Some binaries like glibc have special symbols which are on the symbol
389  * table, but not in the debuginfo. If we can find the address of the
390  * symbol from map, we can translate the address back to the probe point.
391  */
392 static int find_alternative_probe_point(struct debuginfo *dinfo,
393 					struct perf_probe_point *pp,
394 					struct perf_probe_point *result,
395 					const char *target, struct nsinfo *nsi,
396 					bool uprobes)
397 {
398 	struct map *map = NULL;
399 	struct symbol *sym;
400 	u64 address = 0;
401 	int ret = -ENOENT;
402 	size_t idx;
403 
404 	/* This can work only for function-name based one */
405 	if (!pp->function || pp->file)
406 		return -ENOTSUP;
407 
408 	map = get_target_map(target, nsi, uprobes);
409 	if (!map)
410 		return -EINVAL;
411 
412 	/* Find the address of given function */
413 	map__for_each_symbol_by_name(map, pp->function, sym, idx) {
414 		if (uprobes) {
415 			address = sym->start;
416 			if (sym->type == STT_GNU_IFUNC)
417 				pr_warning("Warning: The probe function (%s) is a GNU indirect function.\n"
418 					   "Consider identifying the final function used at run time and set the probe directly on that.\n",
419 					   pp->function);
420 		} else
421 			address = map__unmap_ip(map, sym->start) - map__reloc(map);
422 		break;
423 	}
424 	if (!address) {
425 		ret = -ENOENT;
426 		goto out;
427 	}
428 	pr_debug("Symbol %s address found : %" PRIx64 "\n",
429 			pp->function, address);
430 
431 	ret = debuginfo__find_probe_point(dinfo, address, result);
432 	if (ret <= 0)
433 		ret = (!ret) ? -ENOENT : ret;
434 	else {
435 		result->offset += pp->offset;
436 		result->line += pp->line;
437 		result->retprobe = pp->retprobe;
438 		ret = 0;
439 	}
440 
441 out:
442 	map__put(map);
443 	return ret;
444 
445 }
446 
447 static int get_alternative_probe_event(struct debuginfo *dinfo,
448 				       struct perf_probe_event *pev,
449 				       struct perf_probe_point *tmp)
450 {
451 	int ret;
452 
453 	memcpy(tmp, &pev->point, sizeof(*tmp));
454 	memset(&pev->point, 0, sizeof(pev->point));
455 	ret = find_alternative_probe_point(dinfo, tmp, &pev->point, pev->target,
456 					   pev->nsi, pev->uprobes);
457 	if (ret < 0)
458 		memcpy(&pev->point, tmp, sizeof(*tmp));
459 
460 	return ret;
461 }
462 
463 static int get_alternative_line_range(struct debuginfo *dinfo,
464 				      struct line_range *lr,
465 				      const char *target, bool user)
466 {
467 	struct perf_probe_point pp = { .function = lr->function,
468 				       .file = lr->file,
469 				       .line = lr->start };
470 	struct perf_probe_point result;
471 	int ret, len = 0;
472 
473 	memset(&result, 0, sizeof(result));
474 
475 	if (lr->end != INT_MAX)
476 		len = lr->end - lr->start;
477 	ret = find_alternative_probe_point(dinfo, &pp, &result,
478 					   target, NULL, user);
479 	if (!ret) {
480 		lr->function = result.function;
481 		lr->file = result.file;
482 		lr->start = result.line;
483 		if (lr->end != INT_MAX)
484 			lr->end = lr->start + len;
485 		clear_perf_probe_point(&pp);
486 	}
487 	return ret;
488 }
489 
490 #ifdef HAVE_DEBUGINFOD_SUPPORT
491 static struct debuginfo *open_from_debuginfod(struct dso *dso, struct nsinfo *nsi,
492 					      bool silent)
493 {
494 	debuginfod_client *c = debuginfod_begin();
495 	char sbuild_id[SBUILD_ID_SIZE + 1];
496 	struct debuginfo *ret = NULL;
497 	struct nscookie nsc;
498 	char *path;
499 	int fd;
500 
501 	if (!c)
502 		return NULL;
503 
504 	build_id__sprintf(dso__bid(dso), sbuild_id);
505 	fd = debuginfod_find_debuginfo(c, (const unsigned char *)sbuild_id,
506 					0, &path);
507 	if (fd >= 0)
508 		close(fd);
509 	debuginfod_end(c);
510 	if (fd < 0) {
511 		if (!silent)
512 			pr_debug("Failed to find debuginfo in debuginfod.\n");
513 		return NULL;
514 	}
515 	if (!silent)
516 		pr_debug("Load debuginfo from debuginfod (%s)\n", path);
517 
518 	nsinfo__mountns_enter(nsi, &nsc);
519 	ret = debuginfo__new((const char *)path);
520 	nsinfo__mountns_exit(&nsc);
521 	return ret;
522 }
523 #else
524 static inline
525 struct debuginfo *open_from_debuginfod(struct dso *dso __maybe_unused,
526 				       struct nsinfo *nsi __maybe_unused,
527 				       bool silent __maybe_unused)
528 {
529 	return NULL;
530 }
531 #endif
532 
533 /* Open new debuginfo of given module */
534 static struct debuginfo *open_debuginfo(const char *module, struct nsinfo *nsi,
535 					bool silent)
536 {
537 	const char *path = module;
538 	char reason[STRERR_BUFSIZE];
539 	struct debuginfo *ret = NULL;
540 	struct dso *dso = NULL;
541 	struct nscookie nsc;
542 	int err;
543 
544 	if (!module || !strchr(module, '/')) {
545 		err = kernel_get_module_dso(module, &dso);
546 		if (err < 0) {
547 			if (!dso || *dso__load_errno(dso) == 0) {
548 				if (!str_error_r(-err, reason, STRERR_BUFSIZE))
549 					strcpy(reason, "(unknown)");
550 			} else
551 				dso__strerror_load(dso, reason, STRERR_BUFSIZE);
552 			if (dso)
553 				ret = open_from_debuginfod(dso, nsi, silent);
554 			if (ret)
555 				return ret;
556 			if (!silent) {
557 				if (module)
558 					pr_err("Module %s is not loaded, please specify its full path name.\n", module);
559 				else
560 					pr_err("Failed to find the path for the kernel: %s\n", reason);
561 			}
562 			return NULL;
563 		}
564 		path = dso__long_name(dso);
565 	}
566 	nsinfo__mountns_enter(nsi, &nsc);
567 	ret = debuginfo__new(path);
568 	if (!ret && !silent) {
569 		pr_warning("The %s file has no debug information.\n", path);
570 		if (!module || !strtailcmp(path, ".ko"))
571 			pr_warning("Rebuild with CONFIG_DEBUG_INFO=y, ");
572 		else
573 			pr_warning("Rebuild with -g, ");
574 		pr_warning("or install an appropriate debuginfo package.\n");
575 	}
576 	nsinfo__mountns_exit(&nsc);
577 	return ret;
578 }
579 
580 /* For caching the last debuginfo */
581 static struct debuginfo *debuginfo_cache;
582 static char *debuginfo_cache_path;
583 
584 static struct debuginfo *debuginfo_cache__open(const char *module, bool silent)
585 {
586 	const char *path = module;
587 
588 	/* If the module is NULL, it should be the kernel. */
589 	if (!module)
590 		path = "kernel";
591 
592 	if (debuginfo_cache_path && !strcmp(debuginfo_cache_path, path))
593 		goto out;
594 
595 	/* Copy module path */
596 	free(debuginfo_cache_path);
597 	debuginfo_cache_path = strdup(path);
598 	if (!debuginfo_cache_path) {
599 		debuginfo__delete(debuginfo_cache);
600 		debuginfo_cache = NULL;
601 		goto out;
602 	}
603 
604 	debuginfo_cache = open_debuginfo(module, NULL, silent);
605 	if (!debuginfo_cache)
606 		zfree(&debuginfo_cache_path);
607 out:
608 	return debuginfo_cache;
609 }
610 
611 static void debuginfo_cache__exit(void)
612 {
613 	debuginfo__delete(debuginfo_cache);
614 	debuginfo_cache = NULL;
615 	zfree(&debuginfo_cache_path);
616 }
617 
618 
619 static int get_text_start_address(const char *exec, u64 *address,
620 				  struct nsinfo *nsi)
621 {
622 	Elf *elf;
623 	GElf_Ehdr ehdr;
624 	GElf_Shdr shdr;
625 	int fd, ret = -ENOENT;
626 	struct nscookie nsc;
627 
628 	nsinfo__mountns_enter(nsi, &nsc);
629 	fd = open(exec, O_RDONLY);
630 	nsinfo__mountns_exit(&nsc);
631 	if (fd < 0)
632 		return -errno;
633 
634 	elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
635 	if (elf == NULL) {
636 		ret = -EINVAL;
637 		goto out_close;
638 	}
639 
640 	if (gelf_getehdr(elf, &ehdr) == NULL)
641 		goto out;
642 
643 	if (!elf_section_by_name(elf, &ehdr, &shdr, ".text", NULL))
644 		goto out;
645 
646 	*address = shdr.sh_addr - shdr.sh_offset;
647 	ret = 0;
648 out:
649 	elf_end(elf);
650 out_close:
651 	close(fd);
652 
653 	return ret;
654 }
655 
656 /*
657  * Convert trace point to probe point with debuginfo
658  */
659 static int find_perf_probe_point_from_dwarf(struct probe_trace_point *tp,
660 					    struct perf_probe_point *pp,
661 					    bool is_kprobe)
662 {
663 	struct debuginfo *dinfo = NULL;
664 	u64 stext = 0;
665 	u64 addr = tp->address;
666 	int ret = -ENOENT;
667 
668 	/* convert the address to dwarf address */
669 	if (!is_kprobe) {
670 		if (!addr) {
671 			ret = -EINVAL;
672 			goto error;
673 		}
674 		ret = get_text_start_address(tp->module, &stext, NULL);
675 		if (ret < 0)
676 			goto error;
677 		addr += stext;
678 	} else if (tp->symbol) {
679 		/* If the module is given, this returns relative address */
680 		ret = kernel_get_symbol_address_by_name(tp->symbol, &addr,
681 							false, !!tp->module);
682 		if (ret != 0)
683 			goto error;
684 		addr += tp->offset;
685 	}
686 
687 	pr_debug("try to find information at %" PRIx64 " in %s\n", addr,
688 		 tp->module ? : "kernel");
689 
690 	dinfo = debuginfo_cache__open(tp->module, verbose <= 0);
691 	if (dinfo)
692 		ret = debuginfo__find_probe_point(dinfo, addr, pp);
693 	else
694 		ret = -ENOENT;
695 
696 	if (ret > 0) {
697 		pp->retprobe = tp->retprobe;
698 		return 0;
699 	}
700 error:
701 	pr_debug("Failed to find corresponding probes from debuginfo.\n");
702 	return ret ? : -ENOENT;
703 }
704 
705 /* Adjust symbol name and address */
706 static int post_process_probe_trace_point(struct probe_trace_point *tp,
707 					   struct map *map, u64 offs)
708 {
709 	struct symbol *sym;
710 	u64 addr = tp->address - offs;
711 
712 	sym = map__find_symbol(map, addr);
713 	if (!sym) {
714 		/*
715 		 * If the address is in the inittext section, map can not
716 		 * find it. Ignore it if we are probing offline kernel.
717 		 */
718 		return (symbol_conf.ignore_vmlinux_buildid) ? 0 : -ENOENT;
719 	}
720 
721 	if (strcmp(sym->name, tp->symbol)) {
722 		/* If we have no realname, use symbol for it */
723 		if (!tp->realname)
724 			tp->realname = tp->symbol;
725 		else
726 			free(tp->symbol);
727 		tp->symbol = strdup(sym->name);
728 		if (!tp->symbol)
729 			return -ENOMEM;
730 	}
731 	tp->offset = addr - sym->start;
732 	tp->address -= offs;
733 
734 	return 0;
735 }
736 
737 /*
738  * Rename DWARF symbols to ELF symbols -- gcc sometimes optimizes functions
739  * and generate new symbols with suffixes such as .constprop.N or .isra.N
740  * etc. Since those symbols are not recorded in DWARF, we have to find
741  * correct generated symbols from offline ELF binary.
742  * For online kernel or uprobes we don't need this because those are
743  * rebased on _text, or already a section relative address.
744  */
745 static int
746 post_process_offline_probe_trace_events(struct probe_trace_event *tevs,
747 					int ntevs, const char *pathname)
748 {
749 	struct map *map;
750 	u64 stext = 0;
751 	int i, ret = 0;
752 
753 	/* Prepare a map for offline binary */
754 	map = dso__new_map(pathname);
755 	if (!map || get_text_start_address(pathname, &stext, NULL) < 0) {
756 		pr_warning("Failed to get ELF symbols for %s\n", pathname);
757 		return -EINVAL;
758 	}
759 
760 	for (i = 0; i < ntevs; i++) {
761 		ret = post_process_probe_trace_point(&tevs[i].point,
762 						     map, stext);
763 		if (ret < 0)
764 			break;
765 	}
766 	map__put(map);
767 
768 	return ret;
769 }
770 
771 static int add_exec_to_probe_trace_events(struct probe_trace_event *tevs,
772 					  int ntevs, const char *exec,
773 					  struct nsinfo *nsi)
774 {
775 	int i, ret = 0;
776 	u64 stext = 0;
777 
778 	if (!exec)
779 		return 0;
780 
781 	ret = get_text_start_address(exec, &stext, nsi);
782 	if (ret < 0)
783 		return ret;
784 
785 	for (i = 0; i < ntevs && ret >= 0; i++) {
786 		/* point.address is the address of point.symbol + point.offset */
787 		tevs[i].point.address -= stext;
788 		tevs[i].point.module = strdup(exec);
789 		if (!tevs[i].point.module) {
790 			ret = -ENOMEM;
791 			break;
792 		}
793 		tevs[i].uprobes = true;
794 	}
795 
796 	return ret;
797 }
798 
799 static int
800 post_process_module_probe_trace_events(struct probe_trace_event *tevs,
801 				       int ntevs, const char *module,
802 				       struct debuginfo *dinfo)
803 {
804 	Dwarf_Addr text_offs = 0;
805 	int i, ret = 0;
806 	char *mod_name = NULL;
807 	struct map *map;
808 
809 	if (!module)
810 		return 0;
811 
812 	map = get_target_map(module, NULL, false);
813 	if (!map || debuginfo__get_text_offset(dinfo, &text_offs, true) < 0) {
814 		pr_warning("Failed to get ELF symbols for %s\n", module);
815 		return -EINVAL;
816 	}
817 
818 	mod_name = find_module_name(module);
819 	for (i = 0; i < ntevs; i++) {
820 		ret = post_process_probe_trace_point(&tevs[i].point,
821 						map, text_offs);
822 		if (ret < 0)
823 			break;
824 		tevs[i].point.module =
825 			strdup(mod_name ? mod_name : module);
826 		if (!tevs[i].point.module) {
827 			ret = -ENOMEM;
828 			break;
829 		}
830 	}
831 
832 	free(mod_name);
833 	map__put(map);
834 
835 	return ret;
836 }
837 
838 static int
839 post_process_kernel_probe_trace_events(struct probe_trace_event *tevs,
840 				       int ntevs)
841 {
842 	struct ref_reloc_sym *reloc_sym;
843 	struct map *map;
844 	char *tmp;
845 	int i, skipped = 0;
846 
847 	/* Skip post process if the target is an offline kernel */
848 	if (symbol_conf.ignore_vmlinux_buildid)
849 		return post_process_offline_probe_trace_events(tevs, ntevs,
850 						symbol_conf.vmlinux_name);
851 
852 	reloc_sym = kernel_get_ref_reloc_sym(&map);
853 	if (!reloc_sym) {
854 		pr_warning("Relocated base symbol is not found! "
855 			   "Check /proc/sys/kernel/kptr_restrict\n"
856 			   "and /proc/sys/kernel/perf_event_paranoid. "
857 			   "Or run as privileged perf user.\n\n");
858 		return -EINVAL;
859 	}
860 
861 	for (i = 0; i < ntevs; i++) {
862 		if (!tevs[i].point.address)
863 			continue;
864 		if (tevs[i].point.retprobe && !kretprobe_offset_is_supported())
865 			continue;
866 		/*
867 		 * If we found a wrong one, mark it by NULL symbol.
868 		 * Since addresses in debuginfo is same as objdump, we need
869 		 * to convert it to addresses on memory.
870 		 */
871 		if (kprobe_warn_out_range(tevs[i].point.symbol,
872 			map__objdump_2mem(map, tevs[i].point.address))) {
873 			tmp = NULL;
874 			skipped++;
875 		} else {
876 			tmp = strdup(reloc_sym->name);
877 			if (!tmp)
878 				return -ENOMEM;
879 		}
880 		/* If we have no realname, use symbol for it */
881 		if (!tevs[i].point.realname)
882 			tevs[i].point.realname = tevs[i].point.symbol;
883 		else
884 			free(tevs[i].point.symbol);
885 		tevs[i].point.symbol = tmp;
886 		tevs[i].point.offset = tevs[i].point.address -
887 			(map__reloc(map) ? reloc_sym->unrelocated_addr :
888 				      reloc_sym->addr);
889 	}
890 	return skipped;
891 }
892 
893 void __weak
894 arch__post_process_probe_trace_events(struct perf_probe_event *pev __maybe_unused,
895 				      int ntevs __maybe_unused)
896 {
897 }
898 
899 /* Post processing the probe events */
900 static int post_process_probe_trace_events(struct perf_probe_event *pev,
901 					   struct probe_trace_event *tevs,
902 					   int ntevs, const char *module,
903 					   bool uprobe, struct debuginfo *dinfo)
904 {
905 	int ret;
906 
907 	if (uprobe)
908 		ret = add_exec_to_probe_trace_events(tevs, ntevs, module,
909 						     pev->nsi);
910 	else if (module)
911 		/* Currently ref_reloc_sym based probe is not for drivers */
912 		ret = post_process_module_probe_trace_events(tevs, ntevs,
913 							     module, dinfo);
914 	else
915 		ret = post_process_kernel_probe_trace_events(tevs, ntevs);
916 
917 	if (ret >= 0)
918 		arch__post_process_probe_trace_events(pev, ntevs);
919 
920 	return ret;
921 }
922 
923 /* Try to find perf_probe_event with debuginfo */
924 static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
925 					  struct probe_trace_event **tevs)
926 {
927 	bool need_dwarf = perf_probe_event_need_dwarf(pev);
928 	struct perf_probe_point tmp;
929 	struct debuginfo *dinfo;
930 	int ntevs, ret = 0;
931 
932 	/* Workaround for gcc #98776 issue.
933 	 * Perf failed to add kretprobe event with debuginfo of vmlinux which is
934 	 * compiled by gcc with -fpatchable-function-entry option enabled. The
935 	 * same issue with kernel module. The retprobe doesn`t need debuginfo.
936 	 * This workaround solution use map to query the probe function address
937 	 * for retprobe event.
938 	 */
939 	if (pev->point.retprobe)
940 		return 0;
941 
942 	dinfo = open_debuginfo(pev->target, pev->nsi, !need_dwarf);
943 	if (!dinfo) {
944 		if (need_dwarf)
945 			return -ENODATA;
946 		pr_debug("Could not open debuginfo. Try to use symbols.\n");
947 		return 0;
948 	}
949 
950 	pr_debug("Try to find probe point from debuginfo.\n");
951 	/* Searching trace events corresponding to a probe event */
952 	ntevs = debuginfo__find_trace_events(dinfo, pev, tevs);
953 
954 	if (ntevs == 0)	{  /* Not found, retry with an alternative */
955 		ret = get_alternative_probe_event(dinfo, pev, &tmp);
956 		if (!ret) {
957 			ntevs = debuginfo__find_trace_events(dinfo, pev, tevs);
958 			/*
959 			 * Write back to the original probe_event for
960 			 * setting appropriate (user given) event name
961 			 */
962 			clear_perf_probe_point(&pev->point);
963 			memcpy(&pev->point, &tmp, sizeof(tmp));
964 		}
965 	}
966 
967 	if (ntevs > 0) {	/* Succeeded to find trace events */
968 		pr_debug("Found %d probe_trace_events.\n", ntevs);
969 		ret = post_process_probe_trace_events(pev, *tevs, ntevs,
970 					pev->target, pev->uprobes, dinfo);
971 		if (ret < 0 || ret == ntevs) {
972 			pr_debug("Post processing failed or all events are skipped. (%d)\n", ret);
973 			clear_probe_trace_events(*tevs, ntevs);
974 			zfree(tevs);
975 			ntevs = 0;
976 		}
977 	}
978 
979 	debuginfo__delete(dinfo);
980 
981 	if (ntevs == 0)	{	/* No error but failed to find probe point. */
982 		char *probe_point = synthesize_perf_probe_point(&pev->point);
983 		pr_warning("Probe point '%s' not found.\n", probe_point);
984 		free(probe_point);
985 		return -ENODEV;
986 	} else if (ntevs < 0) {
987 		/* Error path : ntevs < 0 */
988 		pr_debug("An error occurred in debuginfo analysis (%d).\n", ntevs);
989 		if (ntevs == -EBADF)
990 			pr_warning("Warning: No dwarf info found in the vmlinux - "
991 				"please rebuild kernel with CONFIG_DEBUG_INFO=y.\n");
992 		if (!need_dwarf) {
993 			pr_debug("Trying to use symbols.\n");
994 			return 0;
995 		}
996 	}
997 	return ntevs;
998 }
999 
1000 #define LINEBUF_SIZE 256
1001 #define NR_ADDITIONAL_LINES 2
1002 
1003 static int __show_one_line(FILE *fp, int l, bool skip, bool show_num)
1004 {
1005 	char buf[LINEBUF_SIZE], sbuf[STRERR_BUFSIZE];
1006 	const char *color = show_num ? "" : PERF_COLOR_BLUE;
1007 	const char *prefix = NULL;
1008 
1009 	do {
1010 		if (fgets(buf, LINEBUF_SIZE, fp) == NULL)
1011 			goto error;
1012 		if (skip)
1013 			continue;
1014 		if (!prefix) {
1015 			prefix = show_num ? "%7d  " : "         ";
1016 			color_fprintf(stdout, color, prefix, l);
1017 		}
1018 		color_fprintf(stdout, color, "%s", buf);
1019 
1020 	} while (strchr(buf, '\n') == NULL);
1021 
1022 	return 1;
1023 error:
1024 	if (ferror(fp)) {
1025 		pr_warning("File read error: %s\n",
1026 			   str_error_r(errno, sbuf, sizeof(sbuf)));
1027 		return -1;
1028 	}
1029 	return 0;
1030 }
1031 
1032 static int _show_one_line(FILE *fp, int l, bool skip, bool show_num)
1033 {
1034 	int rv = __show_one_line(fp, l, skip, show_num);
1035 	if (rv == 0) {
1036 		pr_warning("Source file is shorter than expected.\n");
1037 		rv = -1;
1038 	}
1039 	return rv;
1040 }
1041 
1042 #define show_one_line_with_num(f,l)	_show_one_line(f,l,false,true)
1043 #define show_one_line(f,l)		_show_one_line(f,l,false,false)
1044 #define skip_one_line(f,l)		_show_one_line(f,l,true,false)
1045 #define show_one_line_or_eof(f,l)	__show_one_line(f,l,false,false)
1046 
1047 /*
1048  * Show line-range always requires debuginfo to find source file and
1049  * line number.
1050  */
1051 static int __show_line_range(struct line_range *lr, const char *module,
1052 			     bool user)
1053 {
1054 	struct build_id bid;
1055 	int l = 1;
1056 	struct int_node *ln;
1057 	struct debuginfo *dinfo;
1058 	FILE *fp;
1059 	int ret;
1060 	char *tmp;
1061 	char sbuf[STRERR_BUFSIZE];
1062 	char sbuild_id[SBUILD_ID_SIZE] = "";
1063 
1064 	/* Search a line range */
1065 	dinfo = open_debuginfo(module, NULL, false);
1066 	if (!dinfo)
1067 		return -ENOENT;
1068 
1069 	ret = debuginfo__find_line_range(dinfo, lr);
1070 	if (!ret) {	/* Not found, retry with an alternative */
1071 		ret = get_alternative_line_range(dinfo, lr, module, user);
1072 		if (!ret)
1073 			ret = debuginfo__find_line_range(dinfo, lr);
1074 	}
1075 	if (dinfo->build_id) {
1076 		build_id__init(&bid, dinfo->build_id, BUILD_ID_SIZE);
1077 		build_id__sprintf(&bid, sbuild_id);
1078 	}
1079 	debuginfo__delete(dinfo);
1080 	if (ret == 0 || ret == -ENOENT) {
1081 		pr_warning("Specified source line is not found.\n");
1082 		return -ENOENT;
1083 	} else if (ret < 0) {
1084 		pr_warning("Debuginfo analysis failed.\n");
1085 		return ret;
1086 	}
1087 
1088 	/* Convert source file path */
1089 	tmp = lr->path;
1090 	ret = find_source_path(tmp, sbuild_id, lr->comp_dir, &lr->path);
1091 
1092 	/* Free old path when new path is assigned */
1093 	if (tmp != lr->path)
1094 		free(tmp);
1095 
1096 	if (ret < 0) {
1097 		pr_warning("Failed to find source file path.\n");
1098 		return ret;
1099 	}
1100 
1101 	setup_pager();
1102 
1103 	if (lr->function)
1104 		fprintf(stdout, "<%s@%s:%d>\n", lr->function, lr->path,
1105 			lr->start - lr->offset);
1106 	else
1107 		fprintf(stdout, "<%s:%d>\n", lr->path, lr->start);
1108 
1109 	fp = fopen(lr->path, "r");
1110 	if (fp == NULL) {
1111 		pr_warning("Failed to open %s: %s\n", lr->path,
1112 			   str_error_r(errno, sbuf, sizeof(sbuf)));
1113 		return -errno;
1114 	}
1115 	/* Skip to starting line number */
1116 	while (l < lr->start) {
1117 		ret = skip_one_line(fp, l++);
1118 		if (ret < 0)
1119 			goto end;
1120 	}
1121 
1122 	intlist__for_each_entry(ln, lr->line_list) {
1123 		for (; ln->i > (unsigned long)l; l++) {
1124 			ret = show_one_line(fp, l - lr->offset);
1125 			if (ret < 0)
1126 				goto end;
1127 		}
1128 		ret = show_one_line_with_num(fp, l++ - lr->offset);
1129 		if (ret < 0)
1130 			goto end;
1131 	}
1132 
1133 	if (lr->end == INT_MAX)
1134 		lr->end = l + NR_ADDITIONAL_LINES;
1135 	while (l <= lr->end) {
1136 		ret = show_one_line_or_eof(fp, l++ - lr->offset);
1137 		if (ret <= 0)
1138 			break;
1139 	}
1140 end:
1141 	fclose(fp);
1142 	return ret;
1143 }
1144 
1145 int show_line_range(struct line_range *lr, const char *module,
1146 		    struct nsinfo *nsi, bool user)
1147 {
1148 	int ret;
1149 	struct nscookie nsc;
1150 
1151 	ret = init_probe_symbol_maps(user);
1152 	if (ret < 0)
1153 		return ret;
1154 	nsinfo__mountns_enter(nsi, &nsc);
1155 	ret = __show_line_range(lr, module, user);
1156 	nsinfo__mountns_exit(&nsc);
1157 	exit_probe_symbol_maps();
1158 
1159 	return ret;
1160 }
1161 
1162 static int show_available_vars_at(struct debuginfo *dinfo,
1163 				  struct perf_probe_event *pev,
1164 				  struct strfilter *_filter)
1165 {
1166 	char *buf;
1167 	int ret, i, nvars;
1168 	struct str_node *node;
1169 	struct variable_list *vls = NULL, *vl;
1170 	struct perf_probe_point tmp;
1171 	const char *var;
1172 
1173 	buf = synthesize_perf_probe_point(&pev->point);
1174 	if (!buf)
1175 		return -EINVAL;
1176 	pr_debug("Searching variables at %s\n", buf);
1177 
1178 	ret = debuginfo__find_available_vars_at(dinfo, pev, &vls);
1179 	if (!ret) {  /* Not found, retry with an alternative */
1180 		ret = get_alternative_probe_event(dinfo, pev, &tmp);
1181 		if (!ret) {
1182 			ret = debuginfo__find_available_vars_at(dinfo, pev,
1183 								&vls);
1184 			/* Release the old probe_point */
1185 			clear_perf_probe_point(&tmp);
1186 		}
1187 	}
1188 	if (ret <= 0) {
1189 		if (ret == 0 || ret == -ENOENT) {
1190 			pr_err("Failed to find the address of %s\n", buf);
1191 			ret = -ENOENT;
1192 		} else
1193 			pr_warning("Debuginfo analysis failed.\n");
1194 		goto end;
1195 	}
1196 
1197 	/* Some variables are found */
1198 	fprintf(stdout, "Available variables at %s\n", buf);
1199 	for (i = 0; i < ret; i++) {
1200 		vl = &vls[i];
1201 		/*
1202 		 * A probe point might be converted to
1203 		 * several trace points.
1204 		 */
1205 		fprintf(stdout, "\t@<%s+%lu>\n", vl->point.symbol,
1206 			vl->point.offset);
1207 		zfree(&vl->point.symbol);
1208 		nvars = 0;
1209 		if (vl->vars) {
1210 			strlist__for_each_entry(node, vl->vars) {
1211 				var = strchr(node->s, '\t') + 1;
1212 				if (strfilter__compare(_filter, var)) {
1213 					fprintf(stdout, "\t\t%s\n", node->s);
1214 					nvars++;
1215 				}
1216 			}
1217 			strlist__delete(vl->vars);
1218 		}
1219 		if (nvars == 0)
1220 			fprintf(stdout, "\t\t(No matched variables)\n");
1221 	}
1222 	free(vls);
1223 end:
1224 	free(buf);
1225 	return ret;
1226 }
1227 
1228 /* Show available variables on given probe point */
1229 int show_available_vars(struct perf_probe_event *pevs, int npevs,
1230 			struct strfilter *_filter)
1231 {
1232 	int i, ret = 0;
1233 	struct debuginfo *dinfo;
1234 
1235 	ret = init_probe_symbol_maps(pevs->uprobes);
1236 	if (ret < 0)
1237 		return ret;
1238 
1239 	dinfo = open_debuginfo(pevs->target, pevs->nsi, false);
1240 	if (!dinfo) {
1241 		ret = -ENOENT;
1242 		goto out;
1243 	}
1244 
1245 	setup_pager();
1246 
1247 	for (i = 0; i < npevs && ret >= 0; i++)
1248 		ret = show_available_vars_at(dinfo, &pevs[i], _filter);
1249 
1250 	debuginfo__delete(dinfo);
1251 out:
1252 	exit_probe_symbol_maps();
1253 	return ret;
1254 }
1255 
1256 #else	/* !HAVE_LIBDW_SUPPORT */
1257 
1258 static void debuginfo_cache__exit(void)
1259 {
1260 }
1261 
1262 static int
1263 find_perf_probe_point_from_dwarf(struct probe_trace_point *tp __maybe_unused,
1264 				 struct perf_probe_point *pp __maybe_unused,
1265 				 bool is_kprobe __maybe_unused)
1266 {
1267 	return -ENOSYS;
1268 }
1269 
1270 static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
1271 				struct probe_trace_event **tevs __maybe_unused)
1272 {
1273 	if (perf_probe_event_need_dwarf(pev)) {
1274 		pr_warning("Debuginfo-analysis is not supported.\n");
1275 		return -ENOSYS;
1276 	}
1277 
1278 	return 0;
1279 }
1280 
1281 int show_line_range(struct line_range *lr __maybe_unused,
1282 		    const char *module __maybe_unused,
1283 		    struct nsinfo *nsi __maybe_unused,
1284 		    bool user __maybe_unused)
1285 {
1286 	pr_warning("Debuginfo-analysis is not supported.\n");
1287 	return -ENOSYS;
1288 }
1289 
1290 int show_available_vars(struct perf_probe_event *pevs __maybe_unused,
1291 			int npevs __maybe_unused,
1292 			struct strfilter *filter __maybe_unused)
1293 {
1294 	pr_warning("Debuginfo-analysis is not supported.\n");
1295 	return -ENOSYS;
1296 }
1297 #endif
1298 
1299 void line_range__clear(struct line_range *lr)
1300 {
1301 	zfree(&lr->function);
1302 	zfree(&lr->file);
1303 	zfree(&lr->path);
1304 	zfree(&lr->comp_dir);
1305 	intlist__delete(lr->line_list);
1306 }
1307 
1308 int line_range__init(struct line_range *lr)
1309 {
1310 	memset(lr, 0, sizeof(*lr));
1311 	lr->line_list = intlist__new(NULL);
1312 	if (!lr->line_list)
1313 		return -ENOMEM;
1314 	else
1315 		return 0;
1316 }
1317 
1318 static int parse_line_num(char **ptr, int *val, const char *what)
1319 {
1320 	const char *start = *ptr;
1321 
1322 	errno = 0;
1323 	*val = strtol(*ptr, ptr, 0);
1324 	if (errno || *ptr == start) {
1325 		semantic_error("'%s' is not a valid number.\n", what);
1326 		return -EINVAL;
1327 	}
1328 	return 0;
1329 }
1330 
1331 /* Check the name is good for event, group or function */
1332 static bool is_c_func_name(const char *name)
1333 {
1334 	if (!isalpha(*name) && *name != '_')
1335 		return false;
1336 	while (*++name != '\0') {
1337 		if (!isalpha(*name) && !isdigit(*name) && *name != '_')
1338 			return false;
1339 	}
1340 	return true;
1341 }
1342 
1343 /*
1344  * Stuff 'lr' according to the line range described by 'arg'.
1345  * The line range syntax is described by:
1346  *
1347  *         SRC[:SLN[+NUM|-ELN]]
1348  *         FNC[@SRC][:SLN[+NUM|-ELN]]
1349  */
1350 int parse_line_range_desc(const char *arg, struct line_range *lr)
1351 {
1352 	char *range, *file, *name = strdup(arg);
1353 	int err;
1354 
1355 	if (!name)
1356 		return -ENOMEM;
1357 
1358 	lr->start = 0;
1359 	lr->end = INT_MAX;
1360 
1361 	range = strchr(name, ':');
1362 	if (range) {
1363 		*range++ = '\0';
1364 
1365 		err = parse_line_num(&range, &lr->start, "start line");
1366 		if (err)
1367 			goto err;
1368 
1369 		if (*range == '+' || *range == '-') {
1370 			const char c = *range++;
1371 
1372 			err = parse_line_num(&range, &lr->end, "end line");
1373 			if (err)
1374 				goto err;
1375 
1376 			if (c == '+') {
1377 				lr->end += lr->start;
1378 				/*
1379 				 * Adjust the number of lines here.
1380 				 * If the number of lines == 1, the
1381 				 * end of line should be equal to
1382 				 * the start of line.
1383 				 */
1384 				lr->end--;
1385 			}
1386 		}
1387 
1388 		pr_debug("Line range is %d to %d\n", lr->start, lr->end);
1389 
1390 		err = -EINVAL;
1391 		if (lr->start > lr->end) {
1392 			semantic_error("Start line must be smaller"
1393 				       " than end line.\n");
1394 			goto err;
1395 		}
1396 		if (*range != '\0') {
1397 			semantic_error("Tailing with invalid str '%s'.\n", range);
1398 			goto err;
1399 		}
1400 	}
1401 
1402 	file = strchr(name, '@');
1403 	if (file) {
1404 		*file = '\0';
1405 		lr->file = strdup(++file);
1406 		if (lr->file == NULL) {
1407 			err = -ENOMEM;
1408 			goto err;
1409 		}
1410 		lr->function = name;
1411 	} else if (strchr(name, '/') || strchr(name, '.'))
1412 		lr->file = name;
1413 	else if (is_c_func_name(name))/* We reuse it for checking funcname */
1414 		lr->function = name;
1415 	else {	/* Invalid name */
1416 		semantic_error("'%s' is not a valid function name.\n", name);
1417 		err = -EINVAL;
1418 		goto err;
1419 	}
1420 
1421 	return 0;
1422 err:
1423 	free(name);
1424 	return err;
1425 }
1426 
1427 static int parse_perf_probe_event_name(char **arg, struct perf_probe_event *pev)
1428 {
1429 	char *ptr;
1430 
1431 	ptr = strpbrk_esc(*arg, ":");
1432 	if (ptr) {
1433 		*ptr = '\0';
1434 		if (!pev->sdt && !is_c_func_name(*arg))
1435 			goto ng_name;
1436 		pev->group = strdup_esc(*arg);
1437 		if (!pev->group)
1438 			return -ENOMEM;
1439 		*arg = ptr + 1;
1440 	} else
1441 		pev->group = NULL;
1442 
1443 	pev->event = strdup_esc(*arg);
1444 	if (pev->event == NULL)
1445 		return -ENOMEM;
1446 
1447 	if (!pev->sdt && !is_c_func_name(pev->event)) {
1448 		zfree(&pev->event);
1449 ng_name:
1450 		zfree(&pev->group);
1451 		semantic_error("%s is bad for event name -it must "
1452 			       "follow C symbol-naming rule.\n", *arg);
1453 		return -EINVAL;
1454 	}
1455 	return 0;
1456 }
1457 
1458 /* Parse probepoint definition. */
1459 static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev)
1460 {
1461 	struct perf_probe_point *pp = &pev->point;
1462 	char *ptr, *tmp;
1463 	char c, nc = 0;
1464 	bool file_spec = false;
1465 	int ret;
1466 
1467 	/*
1468 	 * <Syntax>
1469 	 * perf probe [GRP:][EVENT=]SRC[:LN|;PTN]
1470 	 * perf probe [GRP:][EVENT=]FUNC[@SRC][+OFFS|%return|:LN|;PAT]
1471 	 * perf probe %[GRP:]SDT_EVENT
1472 	 */
1473 	if (!arg)
1474 		return -EINVAL;
1475 
1476 	if (is_sdt_event(arg)) {
1477 		pev->sdt = true;
1478 		if (arg[0] == '%')
1479 			arg++;
1480 	}
1481 
1482 	ptr = strpbrk_esc(arg, ";=@+%");
1483 	if (pev->sdt) {
1484 		if (ptr) {
1485 			if (*ptr != '@') {
1486 				semantic_error("%s must be an SDT name.\n",
1487 					       arg);
1488 				return -EINVAL;
1489 			}
1490 			/* This must be a target file name or build id */
1491 			tmp = build_id_cache__complement(ptr + 1);
1492 			if (tmp) {
1493 				pev->target = build_id_cache__origname(tmp);
1494 				free(tmp);
1495 			} else
1496 				pev->target = strdup_esc(ptr + 1);
1497 			if (!pev->target)
1498 				return -ENOMEM;
1499 			*ptr = '\0';
1500 		}
1501 		ret = parse_perf_probe_event_name(&arg, pev);
1502 		if (ret == 0) {
1503 			if (asprintf(&pev->point.function, "%%%s", pev->event) < 0)
1504 				ret = -errno;
1505 		}
1506 		return ret;
1507 	}
1508 
1509 	if (ptr && *ptr == '=') {	/* Event name */
1510 		*ptr = '\0';
1511 		tmp = ptr + 1;
1512 		ret = parse_perf_probe_event_name(&arg, pev);
1513 		if (ret < 0)
1514 			return ret;
1515 
1516 		arg = tmp;
1517 	}
1518 
1519 	/*
1520 	 * Check arg is function or file name and copy it.
1521 	 *
1522 	 * We consider arg to be a file spec if and only if it satisfies
1523 	 * all of the below criteria::
1524 	 * - it does not include any of "+@%",
1525 	 * - it includes one of ":;", and
1526 	 * - it has a period '.' in the name.
1527 	 *
1528 	 * Otherwise, we consider arg to be a function specification.
1529 	 */
1530 	if (!strpbrk_esc(arg, "+@%")) {
1531 		ptr = strpbrk_esc(arg, ";:");
1532 		/* This is a file spec if it includes a '.' before ; or : */
1533 		if (ptr && memchr(arg, '.', ptr - arg))
1534 			file_spec = true;
1535 	}
1536 
1537 	ptr = strpbrk_esc(arg, ";:+@%");
1538 	if (ptr) {
1539 		nc = *ptr;
1540 		*ptr++ = '\0';
1541 	}
1542 
1543 	if (arg[0] == '\0')
1544 		tmp = NULL;
1545 	else {
1546 		tmp = strdup_esc(arg);
1547 		if (tmp == NULL)
1548 			return -ENOMEM;
1549 	}
1550 
1551 	if (file_spec)
1552 		pp->file = tmp;
1553 	else {
1554 		pp->function = tmp;
1555 
1556 		/*
1557 		 * Keep pp->function even if this is absolute address,
1558 		 * so it can mark whether abs_address is valid.
1559 		 * Which make 'perf probe lib.bin 0x0' possible.
1560 		 *
1561 		 * Note that checking length of tmp is not needed
1562 		 * because when we access tmp[1] we know tmp[0] is '0',
1563 		 * so tmp[1] should always valid (but could be '\0').
1564 		 */
1565 		if (tmp && !strncmp(tmp, "0x", 2)) {
1566 			pp->abs_address = strtoull(pp->function, &tmp, 0);
1567 			if (*tmp != '\0') {
1568 				semantic_error("Invalid absolute address.\n");
1569 				return -EINVAL;
1570 			}
1571 		}
1572 	}
1573 
1574 	/* Parse other options */
1575 	while (ptr) {
1576 		arg = ptr;
1577 		c = nc;
1578 		if (c == ';') {	/* Lazy pattern must be the last part */
1579 			pp->lazy_line = strdup(arg); /* let leave escapes */
1580 			if (pp->lazy_line == NULL)
1581 				return -ENOMEM;
1582 			break;
1583 		}
1584 		ptr = strpbrk_esc(arg, ";:+@%");
1585 		if (ptr) {
1586 			nc = *ptr;
1587 			*ptr++ = '\0';
1588 		}
1589 		switch (c) {
1590 		case ':':	/* Line number */
1591 			pp->line = strtoul(arg, &tmp, 0);
1592 			if (*tmp != '\0') {
1593 				semantic_error("There is non-digit char"
1594 					       " in line number.\n");
1595 				return -EINVAL;
1596 			}
1597 			break;
1598 		case '+':	/* Byte offset from a symbol */
1599 			pp->offset = strtoul(arg, &tmp, 0);
1600 			if (*tmp != '\0') {
1601 				semantic_error("There is non-digit character"
1602 						" in offset.\n");
1603 				return -EINVAL;
1604 			}
1605 			break;
1606 		case '@':	/* File name */
1607 			if (pp->file) {
1608 				semantic_error("SRC@SRC is not allowed.\n");
1609 				return -EINVAL;
1610 			}
1611 			pp->file = strdup_esc(arg);
1612 			if (pp->file == NULL)
1613 				return -ENOMEM;
1614 			break;
1615 		case '%':	/* Probe places */
1616 			if (strcmp(arg, "return") == 0) {
1617 				pp->retprobe = 1;
1618 			} else {	/* Others not supported yet */
1619 				semantic_error("%%%s is not supported.\n", arg);
1620 				return -ENOTSUP;
1621 			}
1622 			break;
1623 		default:	/* Buggy case */
1624 			pr_err("This program has a bug at %s:%d.\n",
1625 				__FILE__, __LINE__);
1626 			return -ENOTSUP;
1627 			break;
1628 		}
1629 	}
1630 
1631 	/* Exclusion check */
1632 	if (pp->lazy_line && pp->line) {
1633 		semantic_error("Lazy pattern can't be used with"
1634 			       " line number.\n");
1635 		return -EINVAL;
1636 	}
1637 
1638 	if (pp->lazy_line && pp->offset) {
1639 		semantic_error("Lazy pattern can't be used with offset.\n");
1640 		return -EINVAL;
1641 	}
1642 
1643 	if (pp->line && pp->offset) {
1644 		semantic_error("Offset can't be used with line number.\n");
1645 		return -EINVAL;
1646 	}
1647 
1648 	if (!pp->line && !pp->lazy_line && pp->file && !pp->function) {
1649 		semantic_error("File always requires line number or "
1650 			       "lazy pattern.\n");
1651 		return -EINVAL;
1652 	}
1653 
1654 	if (pp->offset && !pp->function) {
1655 		semantic_error("Offset requires an entry function.\n");
1656 		return -EINVAL;
1657 	}
1658 
1659 	if ((pp->offset || pp->line || pp->lazy_line) && pp->retprobe) {
1660 		semantic_error("Offset/Line/Lazy pattern can't be used with "
1661 			       "return probe.\n");
1662 		return -EINVAL;
1663 	}
1664 
1665 	pr_debug("symbol:%s file:%s line:%d offset:%lu return:%d lazy:%s\n",
1666 		 pp->function, pp->file, pp->line, pp->offset, pp->retprobe,
1667 		 pp->lazy_line);
1668 	return 0;
1669 }
1670 
1671 /* Parse perf-probe event argument */
1672 static int parse_perf_probe_arg(char *str, struct perf_probe_arg *arg)
1673 {
1674 	char *tmp, *goodname;
1675 	struct perf_probe_arg_field **fieldp;
1676 
1677 	pr_debug("parsing arg: %s into ", str);
1678 
1679 	tmp = strchr(str, '=');
1680 	if (tmp) {
1681 		arg->name = strndup(str, tmp - str);
1682 		if (arg->name == NULL)
1683 			return -ENOMEM;
1684 		pr_debug("name:%s ", arg->name);
1685 		str = tmp + 1;
1686 	}
1687 
1688 	tmp = strchr(str, '@');
1689 	if (tmp && tmp != str && !strcmp(tmp + 1, "user")) { /* user attr */
1690 		if (!user_access_is_supported()) {
1691 			semantic_error("ftrace does not support user access\n");
1692 			return -EINVAL;
1693 		}
1694 		*tmp = '\0';
1695 		arg->user_access = true;
1696 		pr_debug("user_access ");
1697 	}
1698 
1699 	tmp = strchr(str, ':');
1700 	if (tmp) {	/* Type setting */
1701 		*tmp = '\0';
1702 		arg->type = strdup(tmp + 1);
1703 		if (arg->type == NULL)
1704 			return -ENOMEM;
1705 		pr_debug("type:%s ", arg->type);
1706 	}
1707 
1708 	tmp = strpbrk(str, "-.[");
1709 	if (!is_c_varname(str) || !tmp) {
1710 		/* A variable, register, symbol or special value */
1711 		arg->var = strdup(str);
1712 		if (arg->var == NULL)
1713 			return -ENOMEM;
1714 		pr_debug("%s\n", arg->var);
1715 		return 0;
1716 	}
1717 
1718 	/* Structure fields or array element */
1719 	arg->var = strndup(str, tmp - str);
1720 	if (arg->var == NULL)
1721 		return -ENOMEM;
1722 	goodname = arg->var;
1723 	pr_debug("%s, ", arg->var);
1724 	fieldp = &arg->field;
1725 
1726 	do {
1727 		*fieldp = zalloc(sizeof(struct perf_probe_arg_field));
1728 		if (*fieldp == NULL)
1729 			return -ENOMEM;
1730 		if (*tmp == '[') {	/* Array */
1731 			str = tmp;
1732 			(*fieldp)->index = strtol(str + 1, &tmp, 0);
1733 			(*fieldp)->ref = true;
1734 			if (*tmp != ']' || tmp == str + 1) {
1735 				semantic_error("Array index must be a"
1736 						" number.\n");
1737 				return -EINVAL;
1738 			}
1739 			tmp++;
1740 			if (*tmp == '\0')
1741 				tmp = NULL;
1742 		} else {		/* Structure */
1743 			if (*tmp == '.') {
1744 				str = tmp + 1;
1745 				(*fieldp)->ref = false;
1746 			} else if (tmp[1] == '>') {
1747 				str = tmp + 2;
1748 				(*fieldp)->ref = true;
1749 			} else {
1750 				semantic_error("Argument parse error: %s\n",
1751 					       str);
1752 				return -EINVAL;
1753 			}
1754 			tmp = strpbrk(str, "-.[");
1755 		}
1756 		if (tmp) {
1757 			(*fieldp)->name = strndup(str, tmp - str);
1758 			if ((*fieldp)->name == NULL)
1759 				return -ENOMEM;
1760 			if (*str != '[')
1761 				goodname = (*fieldp)->name;
1762 			pr_debug("%s(%d), ", (*fieldp)->name, (*fieldp)->ref);
1763 			fieldp = &(*fieldp)->next;
1764 		}
1765 	} while (tmp);
1766 	(*fieldp)->name = strdup(str);
1767 	if ((*fieldp)->name == NULL)
1768 		return -ENOMEM;
1769 	if (*str != '[')
1770 		goodname = (*fieldp)->name;
1771 	pr_debug("%s(%d)\n", (*fieldp)->name, (*fieldp)->ref);
1772 
1773 	/* If no name is specified, set the last field name (not array index)*/
1774 	if (!arg->name) {
1775 		arg->name = strdup(goodname);
1776 		if (arg->name == NULL)
1777 			return -ENOMEM;
1778 	}
1779 	return 0;
1780 }
1781 
1782 /* Parse perf-probe event command */
1783 int parse_perf_probe_command(const char *cmd, struct perf_probe_event *pev)
1784 {
1785 	char **argv;
1786 	int argc, i, ret = 0;
1787 
1788 	argv = argv_split(cmd, &argc);
1789 	if (!argv) {
1790 		pr_debug("Failed to split arguments.\n");
1791 		return -ENOMEM;
1792 	}
1793 	if (argc - 1 > MAX_PROBE_ARGS) {
1794 		semantic_error("Too many probe arguments (%d).\n", argc - 1);
1795 		ret = -ERANGE;
1796 		goto out;
1797 	}
1798 	/* Parse probe point */
1799 	ret = parse_perf_probe_point(argv[0], pev);
1800 	if (ret < 0)
1801 		goto out;
1802 
1803 	/* Generate event name if needed */
1804 	if (!pev->event && pev->point.function && pev->point.line
1805 			&& !pev->point.lazy_line && !pev->point.offset) {
1806 		if (asprintf(&pev->event, "%s_L%d", pev->point.function,
1807 			pev->point.line) < 0) {
1808 			ret = -ENOMEM;
1809 			goto out;
1810 		}
1811 	}
1812 
1813 	/* Copy arguments and ensure return probe has no C argument */
1814 	pev->nargs = argc - 1;
1815 	pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs);
1816 	if (pev->args == NULL) {
1817 		ret = -ENOMEM;
1818 		goto out;
1819 	}
1820 	for (i = 0; i < pev->nargs && ret >= 0; i++) {
1821 		ret = parse_perf_probe_arg(argv[i + 1], &pev->args[i]);
1822 		if (ret >= 0 &&
1823 		    is_c_varname(pev->args[i].var) && pev->point.retprobe) {
1824 			semantic_error("You can't specify local variable for"
1825 				       " kretprobe.\n");
1826 			ret = -EINVAL;
1827 		}
1828 	}
1829 out:
1830 	argv_free(argv);
1831 
1832 	return ret;
1833 }
1834 
1835 /* Returns true if *any* ARG is either C variable, $params or $vars. */
1836 bool perf_probe_with_var(struct perf_probe_event *pev)
1837 {
1838 	int i = 0;
1839 
1840 	for (i = 0; i < pev->nargs; i++)
1841 		if (is_c_varname(pev->args[i].var)              ||
1842 		    !strcmp(pev->args[i].var, PROBE_ARG_PARAMS) ||
1843 		    !strcmp(pev->args[i].var, PROBE_ARG_VARS))
1844 			return true;
1845 	return false;
1846 }
1847 
1848 /* Return true if this perf_probe_event requires debuginfo */
1849 bool perf_probe_event_need_dwarf(struct perf_probe_event *pev)
1850 {
1851 	if (pev->point.file || pev->point.line || pev->point.lazy_line)
1852 		return true;
1853 
1854 	if (perf_probe_with_var(pev))
1855 		return true;
1856 
1857 	return false;
1858 }
1859 
1860 /* Parse probe_events event into struct probe_point */
1861 int parse_probe_trace_command(const char *cmd, struct probe_trace_event *tev)
1862 {
1863 	struct probe_trace_point *tp = &tev->point;
1864 	char pr;
1865 	char *p;
1866 	char *argv0_str = NULL, *fmt, *fmt1_str, *fmt2_str, *fmt3_str;
1867 	int ret, i, argc;
1868 	char **argv;
1869 
1870 	pr_debug("Parsing probe_events: %s\n", cmd);
1871 	argv = argv_split(cmd, &argc);
1872 	if (!argv) {
1873 		pr_debug("Failed to split arguments.\n");
1874 		return -ENOMEM;
1875 	}
1876 	if (argc < 2) {
1877 		semantic_error("Too few probe arguments.\n");
1878 		ret = -ERANGE;
1879 		goto out;
1880 	}
1881 
1882 	/* Scan event and group name. */
1883 	argv0_str = strdup(argv[0]);
1884 	if (argv0_str == NULL) {
1885 		ret = -ENOMEM;
1886 		goto out;
1887 	}
1888 	fmt1_str = strtok_r(argv0_str, ":", &fmt);
1889 	fmt2_str = strtok_r(NULL, "/", &fmt);
1890 	fmt3_str = strtok_r(NULL, " \t", &fmt);
1891 	if (fmt1_str == NULL || fmt2_str == NULL || fmt3_str == NULL) {
1892 		semantic_error("Failed to parse event name: %s\n", argv[0]);
1893 		ret = -EINVAL;
1894 		goto out;
1895 	}
1896 	pr = fmt1_str[0];
1897 	tev->group = strdup(fmt2_str);
1898 	tev->event = strdup(fmt3_str);
1899 	if (tev->group == NULL || tev->event == NULL) {
1900 		ret = -ENOMEM;
1901 		goto out;
1902 	}
1903 	pr_debug("Group:%s Event:%s probe:%c\n", tev->group, tev->event, pr);
1904 
1905 	tp->retprobe = (pr == 'r');
1906 
1907 	/* Scan module name(if there), function name and offset */
1908 	p = strchr(argv[1], ':');
1909 	if (p) {
1910 		tp->module = strndup(argv[1], p - argv[1]);
1911 		if (!tp->module) {
1912 			ret = -ENOMEM;
1913 			goto out;
1914 		}
1915 		tev->uprobes = (tp->module[0] == '/');
1916 		p++;
1917 	} else
1918 		p = argv[1];
1919 	fmt1_str = strtok_r(p, "+", &fmt);
1920 	/* only the address started with 0x */
1921 	if (fmt1_str[0] == '0')	{
1922 		/*
1923 		 * Fix a special case:
1924 		 * if address == 0, kernel reports something like:
1925 		 * p:probe_libc/abs_0 /lib/libc-2.18.so:0x          (null) arg1=%ax
1926 		 * Newer kernel may fix that, but we want to
1927 		 * support old kernel also.
1928 		 */
1929 		if (strcmp(fmt1_str, "0x") == 0) {
1930 			if (!argv[2] || strcmp(argv[2], "(null)")) {
1931 				ret = -EINVAL;
1932 				goto out;
1933 			}
1934 			tp->address = 0;
1935 
1936 			free(argv[2]);
1937 			for (i = 2; argv[i + 1] != NULL; i++)
1938 				argv[i] = argv[i + 1];
1939 
1940 			argv[i] = NULL;
1941 			argc -= 1;
1942 		} else
1943 			tp->address = strtoull(fmt1_str, NULL, 0);
1944 	} else {
1945 		/* Only the symbol-based probe has offset */
1946 		tp->symbol = strdup(fmt1_str);
1947 		if (tp->symbol == NULL) {
1948 			ret = -ENOMEM;
1949 			goto out;
1950 		}
1951 		fmt2_str = strtok_r(NULL, "", &fmt);
1952 		if (fmt2_str == NULL)
1953 			tp->offset = 0;
1954 		else
1955 			tp->offset = strtoul(fmt2_str, NULL, 10);
1956 	}
1957 
1958 	if (tev->uprobes) {
1959 		fmt2_str = strchr(p, '(');
1960 		if (fmt2_str)
1961 			tp->ref_ctr_offset = strtoul(fmt2_str + 1, NULL, 0);
1962 	}
1963 
1964 	tev->nargs = argc - 2;
1965 	tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
1966 	if (tev->args == NULL) {
1967 		ret = -ENOMEM;
1968 		goto out;
1969 	}
1970 	for (i = 0; i < tev->nargs; i++) {
1971 		p = strchr(argv[i + 2], '=');
1972 		if (p)	/* We don't need which register is assigned. */
1973 			*p++ = '\0';
1974 		else
1975 			p = argv[i + 2];
1976 		tev->args[i].name = strdup(argv[i + 2]);
1977 		/* TODO: parse regs and offset */
1978 		tev->args[i].value = strdup(p);
1979 		if (tev->args[i].name == NULL || tev->args[i].value == NULL) {
1980 			ret = -ENOMEM;
1981 			goto out;
1982 		}
1983 	}
1984 	ret = 0;
1985 out:
1986 	free(argv0_str);
1987 	argv_free(argv);
1988 	return ret;
1989 }
1990 
1991 /* Compose only probe arg */
1992 char *synthesize_perf_probe_arg(struct perf_probe_arg *pa)
1993 {
1994 	struct perf_probe_arg_field *field = pa->field;
1995 	struct strbuf buf;
1996 	char *ret = NULL;
1997 	int err;
1998 
1999 	if (strbuf_init(&buf, 64) < 0)
2000 		return NULL;
2001 
2002 	if (pa->name && pa->var)
2003 		err = strbuf_addf(&buf, "%s=%s", pa->name, pa->var);
2004 	else
2005 		err = strbuf_addstr(&buf, pa->name ?: pa->var);
2006 	if (err)
2007 		goto out;
2008 
2009 	while (field) {
2010 		if (field->name[0] == '[')
2011 			err = strbuf_addstr(&buf, field->name);
2012 		else
2013 			err = strbuf_addf(&buf, "%s%s", field->ref ? "->" : ".",
2014 					  field->name);
2015 		field = field->next;
2016 		if (err)
2017 			goto out;
2018 	}
2019 
2020 	if (pa->type)
2021 		if (strbuf_addf(&buf, ":%s", pa->type) < 0)
2022 			goto out;
2023 
2024 	ret = strbuf_detach(&buf, NULL);
2025 out:
2026 	strbuf_release(&buf);
2027 	return ret;
2028 }
2029 
2030 /* Compose only probe point (not argument) */
2031 static char *synthesize_perf_probe_point(struct perf_probe_point *pp)
2032 {
2033 	struct strbuf buf;
2034 	char *tmp, *ret = NULL;
2035 	int len, err = 0;
2036 
2037 	if (strbuf_init(&buf, 64) < 0)
2038 		return NULL;
2039 
2040 	if (pp->function) {
2041 		if (strbuf_addstr(&buf, pp->function) < 0)
2042 			goto out;
2043 		if (pp->offset)
2044 			err = strbuf_addf(&buf, "+%lu", pp->offset);
2045 		else if (pp->line)
2046 			err = strbuf_addf(&buf, ":%d", pp->line);
2047 		else if (pp->retprobe)
2048 			err = strbuf_addstr(&buf, "%return");
2049 		if (err)
2050 			goto out;
2051 	}
2052 	if (pp->file) {
2053 		tmp = pp->file;
2054 		len = strlen(tmp);
2055 		if (len > 30) {
2056 			tmp = strchr(pp->file + len - 30, '/');
2057 			tmp = tmp ? tmp + 1 : pp->file + len - 30;
2058 		}
2059 		err = strbuf_addf(&buf, "@%s", tmp);
2060 		if (!err && !pp->function && pp->line)
2061 			err = strbuf_addf(&buf, ":%d", pp->line);
2062 	}
2063 	if (!err)
2064 		ret = strbuf_detach(&buf, NULL);
2065 out:
2066 	strbuf_release(&buf);
2067 	return ret;
2068 }
2069 
2070 char *synthesize_perf_probe_command(struct perf_probe_event *pev)
2071 {
2072 	struct strbuf buf;
2073 	char *tmp, *ret = NULL;
2074 	int i;
2075 
2076 	if (strbuf_init(&buf, 64))
2077 		return NULL;
2078 	if (pev->event)
2079 		if (strbuf_addf(&buf, "%s:%s=", pev->group ?: PERFPROBE_GROUP,
2080 				pev->event) < 0)
2081 			goto out;
2082 
2083 	tmp = synthesize_perf_probe_point(&pev->point);
2084 	if (!tmp || strbuf_addstr(&buf, tmp) < 0) {
2085 		free(tmp);
2086 		goto out;
2087 	}
2088 	free(tmp);
2089 
2090 	for (i = 0; i < pev->nargs; i++) {
2091 		tmp = synthesize_perf_probe_arg(pev->args + i);
2092 		if (!tmp || strbuf_addf(&buf, " %s", tmp) < 0) {
2093 			free(tmp);
2094 			goto out;
2095 		}
2096 		free(tmp);
2097 	}
2098 
2099 	ret = strbuf_detach(&buf, NULL);
2100 out:
2101 	strbuf_release(&buf);
2102 	return ret;
2103 }
2104 
2105 static int __synthesize_probe_trace_arg_ref(struct probe_trace_arg_ref *ref,
2106 					    struct strbuf *buf, int depth)
2107 {
2108 	int err;
2109 	if (ref->next) {
2110 		depth = __synthesize_probe_trace_arg_ref(ref->next, buf,
2111 							 depth + 1);
2112 		if (depth < 0)
2113 			return depth;
2114 	}
2115 	if (ref->user_access)
2116 		err = strbuf_addf(buf, "%s%ld(", "+u", ref->offset);
2117 	else
2118 		err = strbuf_addf(buf, "%+ld(", ref->offset);
2119 	return (err < 0) ? err : depth;
2120 }
2121 
2122 static int synthesize_probe_trace_arg(struct probe_trace_arg *arg,
2123 				      struct strbuf *buf)
2124 {
2125 	struct probe_trace_arg_ref *ref = arg->ref;
2126 	int depth = 0, err;
2127 
2128 	/* Argument name or separator */
2129 	if (arg->name)
2130 		err = strbuf_addf(buf, " %s=", arg->name);
2131 	else
2132 		err = strbuf_addch(buf, ' ');
2133 	if (err)
2134 		return err;
2135 
2136 	/* Special case: @XXX */
2137 	if (arg->value[0] == '@' && arg->ref)
2138 			ref = ref->next;
2139 
2140 	/* Dereferencing arguments */
2141 	if (ref) {
2142 		depth = __synthesize_probe_trace_arg_ref(ref, buf, 1);
2143 		if (depth < 0)
2144 			return depth;
2145 	}
2146 
2147 	/* Print argument value */
2148 	if (arg->value[0] == '@' && arg->ref)
2149 		err = strbuf_addf(buf, "%s%+ld", arg->value, arg->ref->offset);
2150 	else
2151 		err = strbuf_addstr(buf, arg->value);
2152 
2153 	/* Closing */
2154 	while (!err && depth--)
2155 		err = strbuf_addch(buf, ')');
2156 
2157 	/* Print argument type */
2158 	if (!err && arg->type)
2159 		err = strbuf_addf(buf, ":%s", arg->type);
2160 
2161 	return err;
2162 }
2163 
2164 static int
2165 synthesize_probe_trace_args(struct probe_trace_event *tev, struct strbuf *buf)
2166 {
2167 	int i, ret = 0;
2168 
2169 	for (i = 0; i < tev->nargs && ret >= 0; i++)
2170 		ret = synthesize_probe_trace_arg(&tev->args[i], buf);
2171 
2172 	return ret;
2173 }
2174 
2175 static int
2176 synthesize_uprobe_trace_def(struct probe_trace_point *tp, struct strbuf *buf)
2177 {
2178 	int err;
2179 
2180 	/* Uprobes must have tp->module */
2181 	if (!tp->module)
2182 		return -EINVAL;
2183 	/*
2184 	 * If tp->address == 0, then this point must be a
2185 	 * absolute address uprobe.
2186 	 * try_to_find_absolute_address() should have made
2187 	 * tp->symbol to "0x0".
2188 	 */
2189 	if (!tp->address && (!tp->symbol || strcmp(tp->symbol, "0x0")))
2190 		return -EINVAL;
2191 
2192 	/* Use the tp->address for uprobes */
2193 	err = strbuf_addf(buf, "%s:0x%" PRIx64, tp->module, tp->address);
2194 
2195 	if (err >= 0 && tp->ref_ctr_offset) {
2196 		if (!uprobe_ref_ctr_is_supported())
2197 			return -EINVAL;
2198 		err = strbuf_addf(buf, "(0x%lx)", tp->ref_ctr_offset);
2199 	}
2200 	return err >= 0 ? 0 : err;
2201 }
2202 
2203 static int
2204 synthesize_kprobe_trace_def(struct probe_trace_point *tp, struct strbuf *buf)
2205 {
2206 	if (!strncmp(tp->symbol, "0x", 2)) {
2207 		/* Absolute address. See try_to_find_absolute_address() */
2208 		return strbuf_addf(buf, "%s%s0x%" PRIx64, tp->module ?: "",
2209 				  tp->module ? ":" : "", tp->address);
2210 	} else {
2211 		return strbuf_addf(buf, "%s%s%s+%lu", tp->module ?: "",
2212 				tp->module ? ":" : "", tp->symbol, tp->offset);
2213 	}
2214 }
2215 
2216 char *synthesize_probe_trace_command(struct probe_trace_event *tev)
2217 {
2218 	struct probe_trace_point *tp = &tev->point;
2219 	struct strbuf buf;
2220 	char *ret = NULL;
2221 	int err;
2222 
2223 	if (strbuf_init(&buf, 32) < 0)
2224 		return NULL;
2225 
2226 	if (strbuf_addf(&buf, "%c:%s/%s ", tp->retprobe ? 'r' : 'p',
2227 			tev->group, tev->event) < 0)
2228 		goto error;
2229 
2230 	if (tev->uprobes)
2231 		err = synthesize_uprobe_trace_def(tp, &buf);
2232 	else
2233 		err = synthesize_kprobe_trace_def(tp, &buf);
2234 
2235 	if (err >= 0)
2236 		err = synthesize_probe_trace_args(tev, &buf);
2237 
2238 	if (err >= 0)
2239 		ret = strbuf_detach(&buf, NULL);
2240 error:
2241 	strbuf_release(&buf);
2242 	return ret;
2243 }
2244 
2245 static int find_perf_probe_point_from_map(struct probe_trace_point *tp,
2246 					  struct perf_probe_point *pp,
2247 					  bool is_kprobe)
2248 {
2249 	struct symbol *sym = NULL;
2250 	struct map *map = NULL;
2251 	u64 addr = tp->address;
2252 	int ret = -ENOENT;
2253 
2254 	if (!is_kprobe) {
2255 		map = dso__new_map(tp->module);
2256 		if (!map)
2257 			goto out;
2258 		sym = map__find_symbol(map, addr);
2259 	} else {
2260 		if (tp->symbol && !addr) {
2261 			if (kernel_get_symbol_address_by_name(tp->symbol,
2262 						&addr, true, false) < 0)
2263 				goto out;
2264 		}
2265 		if (addr) {
2266 			addr += tp->offset;
2267 			sym = machine__find_kernel_symbol(host_machine, addr, &map);
2268 		}
2269 	}
2270 
2271 	if (!sym)
2272 		goto out;
2273 
2274 	pp->retprobe = tp->retprobe;
2275 	pp->offset = addr - map__unmap_ip(map, sym->start);
2276 	pp->function = strdup(sym->name);
2277 	ret = pp->function ? 0 : -ENOMEM;
2278 
2279 out:
2280 	map__put(map);
2281 
2282 	return ret;
2283 }
2284 
2285 static int convert_to_perf_probe_point(struct probe_trace_point *tp,
2286 				       struct perf_probe_point *pp,
2287 				       bool is_kprobe)
2288 {
2289 	char buf[128];
2290 	int ret;
2291 
2292 	ret = find_perf_probe_point_from_dwarf(tp, pp, is_kprobe);
2293 	if (!ret)
2294 		return 0;
2295 	ret = find_perf_probe_point_from_map(tp, pp, is_kprobe);
2296 	if (!ret)
2297 		return 0;
2298 
2299 	pr_debug("Failed to find probe point from both of dwarf and map.\n");
2300 
2301 	if (tp->symbol) {
2302 		pp->function = strdup(tp->symbol);
2303 		pp->offset = tp->offset;
2304 	} else {
2305 		ret = e_snprintf(buf, 128, "0x%" PRIx64, tp->address);
2306 		if (ret < 0)
2307 			return ret;
2308 		pp->function = strdup(buf);
2309 		pp->offset = 0;
2310 	}
2311 	if (pp->function == NULL)
2312 		return -ENOMEM;
2313 
2314 	pp->retprobe = tp->retprobe;
2315 
2316 	return 0;
2317 }
2318 
2319 static int convert_to_perf_probe_event(struct probe_trace_event *tev,
2320 			       struct perf_probe_event *pev, bool is_kprobe)
2321 {
2322 	struct strbuf buf = STRBUF_INIT;
2323 	int i, ret;
2324 
2325 	/* Convert event/group name */
2326 	pev->event = strdup(tev->event);
2327 	pev->group = strdup(tev->group);
2328 	if (pev->event == NULL || pev->group == NULL)
2329 		return -ENOMEM;
2330 
2331 	/* Convert trace_point to probe_point */
2332 	ret = convert_to_perf_probe_point(&tev->point, &pev->point, is_kprobe);
2333 	if (ret < 0)
2334 		return ret;
2335 
2336 	/* Convert trace_arg to probe_arg */
2337 	pev->nargs = tev->nargs;
2338 	pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs);
2339 	if (pev->args == NULL)
2340 		return -ENOMEM;
2341 	for (i = 0; i < tev->nargs && ret >= 0; i++) {
2342 		if (tev->args[i].name)
2343 			pev->args[i].name = strdup(tev->args[i].name);
2344 		else {
2345 			if ((ret = strbuf_init(&buf, 32)) < 0)
2346 				goto error;
2347 			ret = synthesize_probe_trace_arg(&tev->args[i], &buf);
2348 			pev->args[i].name = strbuf_detach(&buf, NULL);
2349 		}
2350 		if (pev->args[i].name == NULL && ret >= 0)
2351 			ret = -ENOMEM;
2352 	}
2353 error:
2354 	if (ret < 0)
2355 		clear_perf_probe_event(pev);
2356 
2357 	return ret;
2358 }
2359 
2360 void clear_perf_probe_event(struct perf_probe_event *pev)
2361 {
2362 	struct perf_probe_arg_field *field, *next;
2363 	int i;
2364 
2365 	zfree(&pev->event);
2366 	zfree(&pev->group);
2367 	zfree(&pev->target);
2368 	clear_perf_probe_point(&pev->point);
2369 
2370 	for (i = 0; i < pev->nargs; i++) {
2371 		zfree(&pev->args[i].name);
2372 		zfree(&pev->args[i].var);
2373 		zfree(&pev->args[i].type);
2374 		field = pev->args[i].field;
2375 		while (field) {
2376 			next = field->next;
2377 			zfree(&field->name);
2378 			free(field);
2379 			field = next;
2380 		}
2381 	}
2382 	pev->nargs = 0;
2383 	zfree(&pev->args);
2384 }
2385 
2386 #define strdup_or_goto(str, label)	\
2387 ({ char *__p = NULL; if (str && !(__p = strdup(str))) goto label; __p; })
2388 
2389 static int perf_probe_point__copy(struct perf_probe_point *dst,
2390 				  struct perf_probe_point *src)
2391 {
2392 	dst->file = strdup_or_goto(src->file, out_err);
2393 	dst->function = strdup_or_goto(src->function, out_err);
2394 	dst->lazy_line = strdup_or_goto(src->lazy_line, out_err);
2395 	dst->line = src->line;
2396 	dst->retprobe = src->retprobe;
2397 	dst->offset = src->offset;
2398 	return 0;
2399 
2400 out_err:
2401 	clear_perf_probe_point(dst);
2402 	return -ENOMEM;
2403 }
2404 
2405 static int perf_probe_arg__copy(struct perf_probe_arg *dst,
2406 				struct perf_probe_arg *src)
2407 {
2408 	struct perf_probe_arg_field *field, **ppfield;
2409 
2410 	dst->name = strdup_or_goto(src->name, out_err);
2411 	dst->var = strdup_or_goto(src->var, out_err);
2412 	dst->type = strdup_or_goto(src->type, out_err);
2413 
2414 	field = src->field;
2415 	ppfield = &(dst->field);
2416 	while (field) {
2417 		*ppfield = zalloc(sizeof(*field));
2418 		if (!*ppfield)
2419 			goto out_err;
2420 		(*ppfield)->name = strdup_or_goto(field->name, out_err);
2421 		(*ppfield)->index = field->index;
2422 		(*ppfield)->ref = field->ref;
2423 		field = field->next;
2424 		ppfield = &((*ppfield)->next);
2425 	}
2426 	return 0;
2427 out_err:
2428 	return -ENOMEM;
2429 }
2430 
2431 int perf_probe_event__copy(struct perf_probe_event *dst,
2432 			   struct perf_probe_event *src)
2433 {
2434 	int i;
2435 
2436 	dst->event = strdup_or_goto(src->event, out_err);
2437 	dst->group = strdup_or_goto(src->group, out_err);
2438 	dst->target = strdup_or_goto(src->target, out_err);
2439 	dst->uprobes = src->uprobes;
2440 
2441 	if (perf_probe_point__copy(&dst->point, &src->point) < 0)
2442 		goto out_err;
2443 
2444 	dst->args = zalloc(sizeof(struct perf_probe_arg) * src->nargs);
2445 	if (!dst->args)
2446 		goto out_err;
2447 	dst->nargs = src->nargs;
2448 
2449 	for (i = 0; i < src->nargs; i++)
2450 		if (perf_probe_arg__copy(&dst->args[i], &src->args[i]) < 0)
2451 			goto out_err;
2452 	return 0;
2453 
2454 out_err:
2455 	clear_perf_probe_event(dst);
2456 	return -ENOMEM;
2457 }
2458 
2459 void clear_probe_trace_event(struct probe_trace_event *tev)
2460 {
2461 	struct probe_trace_arg_ref *ref, *next;
2462 	int i;
2463 
2464 	zfree(&tev->event);
2465 	zfree(&tev->group);
2466 	zfree(&tev->point.symbol);
2467 	zfree(&tev->point.realname);
2468 	zfree(&tev->point.module);
2469 	for (i = 0; i < tev->nargs; i++) {
2470 		zfree(&tev->args[i].name);
2471 		zfree(&tev->args[i].value);
2472 		zfree(&tev->args[i].type);
2473 		ref = tev->args[i].ref;
2474 		while (ref) {
2475 			next = ref->next;
2476 			free(ref);
2477 			ref = next;
2478 		}
2479 	}
2480 	zfree(&tev->args);
2481 	tev->nargs = 0;
2482 }
2483 
2484 struct kprobe_blacklist_node {
2485 	struct list_head list;
2486 	u64 start;
2487 	u64 end;
2488 	char *symbol;
2489 };
2490 
2491 static void kprobe_blacklist__delete(struct list_head *blacklist)
2492 {
2493 	struct kprobe_blacklist_node *node;
2494 
2495 	while (!list_empty(blacklist)) {
2496 		node = list_first_entry(blacklist,
2497 					struct kprobe_blacklist_node, list);
2498 		list_del_init(&node->list);
2499 		zfree(&node->symbol);
2500 		free(node);
2501 	}
2502 }
2503 
2504 static int kprobe_blacklist__load(struct list_head *blacklist)
2505 {
2506 	struct kprobe_blacklist_node *node;
2507 	const char *__debugfs = debugfs__mountpoint();
2508 	char buf[PATH_MAX], *p;
2509 	FILE *fp;
2510 	int ret;
2511 
2512 	if (__debugfs == NULL)
2513 		return -ENOTSUP;
2514 
2515 	ret = e_snprintf(buf, PATH_MAX, "%s/kprobes/blacklist", __debugfs);
2516 	if (ret < 0)
2517 		return ret;
2518 
2519 	fp = fopen(buf, "r");
2520 	if (!fp)
2521 		return -errno;
2522 
2523 	ret = 0;
2524 	while (fgets(buf, PATH_MAX, fp)) {
2525 		node = zalloc(sizeof(*node));
2526 		if (!node) {
2527 			ret = -ENOMEM;
2528 			break;
2529 		}
2530 		INIT_LIST_HEAD(&node->list);
2531 		list_add_tail(&node->list, blacklist);
2532 		if (sscanf(buf, "0x%" PRIx64 "-0x%" PRIx64, &node->start, &node->end) != 2) {
2533 			ret = -EINVAL;
2534 			break;
2535 		}
2536 		p = strchr(buf, '\t');
2537 		if (p) {
2538 			p++;
2539 			if (p[strlen(p) - 1] == '\n')
2540 				p[strlen(p) - 1] = '\0';
2541 		} else
2542 			p = (char *)"unknown";
2543 		node->symbol = strdup(p);
2544 		if (!node->symbol) {
2545 			ret = -ENOMEM;
2546 			break;
2547 		}
2548 		pr_debug2("Blacklist: 0x%" PRIx64 "-0x%" PRIx64 ", %s\n",
2549 			  node->start, node->end, node->symbol);
2550 		ret++;
2551 	}
2552 	if (ret < 0)
2553 		kprobe_blacklist__delete(blacklist);
2554 	fclose(fp);
2555 
2556 	return ret;
2557 }
2558 
2559 static struct kprobe_blacklist_node *
2560 kprobe_blacklist__find_by_address(struct list_head *blacklist, u64 address)
2561 {
2562 	struct kprobe_blacklist_node *node;
2563 
2564 	list_for_each_entry(node, blacklist, list) {
2565 		if (node->start <= address && address < node->end)
2566 			return node;
2567 	}
2568 
2569 	return NULL;
2570 }
2571 
2572 static LIST_HEAD(kprobe_blacklist);
2573 
2574 static void kprobe_blacklist__init(void)
2575 {
2576 	if (!list_empty(&kprobe_blacklist))
2577 		return;
2578 
2579 	if (kprobe_blacklist__load(&kprobe_blacklist) < 0)
2580 		pr_debug("No kprobe blacklist support, ignored\n");
2581 }
2582 
2583 static void kprobe_blacklist__release(void)
2584 {
2585 	kprobe_blacklist__delete(&kprobe_blacklist);
2586 }
2587 
2588 static bool kprobe_blacklist__listed(u64 address)
2589 {
2590 	return !!kprobe_blacklist__find_by_address(&kprobe_blacklist, address);
2591 }
2592 
2593 static int perf_probe_event__sprintf(const char *group, const char *event,
2594 				     struct perf_probe_event *pev,
2595 				     const char *module,
2596 				     struct strbuf *result)
2597 {
2598 	int i, ret;
2599 	char *buf;
2600 
2601 	if (asprintf(&buf, "%s:%s", group, event) < 0)
2602 		return -errno;
2603 	ret = strbuf_addf(result, "  %-20s (on ", buf);
2604 	free(buf);
2605 	if (ret)
2606 		return ret;
2607 
2608 	/* Synthesize only event probe point */
2609 	buf = synthesize_perf_probe_point(&pev->point);
2610 	if (!buf)
2611 		return -ENOMEM;
2612 	ret = strbuf_addstr(result, buf);
2613 	free(buf);
2614 
2615 	if (!ret && module)
2616 		ret = strbuf_addf(result, " in %s", module);
2617 
2618 	if (!ret && pev->nargs > 0) {
2619 		ret = strbuf_add(result, " with", 5);
2620 		for (i = 0; !ret && i < pev->nargs; i++) {
2621 			buf = synthesize_perf_probe_arg(&pev->args[i]);
2622 			if (!buf)
2623 				return -ENOMEM;
2624 			ret = strbuf_addf(result, " %s", buf);
2625 			free(buf);
2626 		}
2627 	}
2628 	if (!ret)
2629 		ret = strbuf_addch(result, ')');
2630 
2631 	return ret;
2632 }
2633 
2634 /* Show an event */
2635 int show_perf_probe_event(const char *group, const char *event,
2636 			  struct perf_probe_event *pev,
2637 			  const char *module, bool use_stdout)
2638 {
2639 	struct strbuf buf = STRBUF_INIT;
2640 	int ret;
2641 
2642 	ret = perf_probe_event__sprintf(group, event, pev, module, &buf);
2643 	if (ret >= 0) {
2644 		if (use_stdout)
2645 			printf("%s\n", buf.buf);
2646 		else
2647 			pr_info("%s\n", buf.buf);
2648 	}
2649 	strbuf_release(&buf);
2650 
2651 	return ret;
2652 }
2653 
2654 static bool filter_probe_trace_event(struct probe_trace_event *tev,
2655 				     struct strfilter *filter)
2656 {
2657 	char tmp[128];
2658 
2659 	/* At first, check the event name itself */
2660 	if (strfilter__compare(filter, tev->event))
2661 		return true;
2662 
2663 	/* Next, check the combination of name and group */
2664 	if (e_snprintf(tmp, 128, "%s:%s", tev->group, tev->event) < 0)
2665 		return false;
2666 	return strfilter__compare(filter, tmp);
2667 }
2668 
2669 static int __show_perf_probe_events(int fd, bool is_kprobe,
2670 				    struct strfilter *filter)
2671 {
2672 	int ret = 0;
2673 	struct probe_trace_event tev;
2674 	struct perf_probe_event pev;
2675 	struct strlist *rawlist;
2676 	struct str_node *ent;
2677 
2678 	memset(&tev, 0, sizeof(tev));
2679 	memset(&pev, 0, sizeof(pev));
2680 
2681 	rawlist = probe_file__get_rawlist(fd);
2682 	if (!rawlist)
2683 		return -ENOMEM;
2684 
2685 	strlist__for_each_entry(ent, rawlist) {
2686 		ret = parse_probe_trace_command(ent->s, &tev);
2687 		if (ret >= 0) {
2688 			if (!filter_probe_trace_event(&tev, filter))
2689 				goto next;
2690 			ret = convert_to_perf_probe_event(&tev, &pev,
2691 								is_kprobe);
2692 			if (ret < 0)
2693 				goto next;
2694 			ret = show_perf_probe_event(pev.group, pev.event,
2695 						    &pev, tev.point.module,
2696 						    true);
2697 		}
2698 next:
2699 		clear_perf_probe_event(&pev);
2700 		clear_probe_trace_event(&tev);
2701 		if (ret < 0)
2702 			break;
2703 	}
2704 	strlist__delete(rawlist);
2705 	/* Cleanup cached debuginfo if needed */
2706 	debuginfo_cache__exit();
2707 
2708 	return ret;
2709 }
2710 
2711 /* List up current perf-probe events */
2712 int show_perf_probe_events(struct strfilter *filter)
2713 {
2714 	int kp_fd, up_fd, ret;
2715 
2716 	setup_pager();
2717 
2718 	if (probe_conf.cache)
2719 		return probe_cache__show_all_caches(filter);
2720 
2721 	ret = init_probe_symbol_maps(false);
2722 	if (ret < 0)
2723 		return ret;
2724 
2725 	ret = probe_file__open_both(&kp_fd, &up_fd, 0);
2726 	if (ret < 0)
2727 		return ret;
2728 
2729 	if (kp_fd >= 0)
2730 		ret = __show_perf_probe_events(kp_fd, true, filter);
2731 	if (up_fd >= 0 && ret >= 0)
2732 		ret = __show_perf_probe_events(up_fd, false, filter);
2733 	if (kp_fd > 0)
2734 		close(kp_fd);
2735 	if (up_fd > 0)
2736 		close(up_fd);
2737 	exit_probe_symbol_maps();
2738 
2739 	return ret;
2740 }
2741 
2742 static int get_new_event_name(char *buf, size_t len, const char *base,
2743 			      struct strlist *namelist, bool ret_event,
2744 			      bool allow_suffix)
2745 {
2746 	int i, ret;
2747 	char *p, *nbase;
2748 
2749 	if (*base == '.')
2750 		base++;
2751 	nbase = strdup(base);
2752 	if (!nbase)
2753 		return -ENOMEM;
2754 
2755 	/* Cut off the dot suffixes (e.g. .const, .isra) and version suffixes */
2756 	p = strpbrk(nbase, ".@");
2757 	if (p && p != nbase)
2758 		*p = '\0';
2759 
2760 	/* Try no suffix number */
2761 	ret = e_snprintf(buf, len, "%s%s", nbase, ret_event ? "__return" : "");
2762 	if (ret < 0) {
2763 		pr_warning("snprintf() failed: %d; the event name '%s' is too long\n"
2764 			   "  Hint: Set a shorter event with syntax \"EVENT=PROBEDEF\"\n"
2765 			   "        EVENT: Event name (max length: %d bytes).\n",
2766 			   ret, nbase, MAX_EVENT_NAME_LEN);
2767 		goto out;
2768 	}
2769 	if (!strlist__has_entry(namelist, buf))
2770 		goto out;
2771 
2772 	if (!allow_suffix) {
2773 		pr_warning("Error: event \"%s\" already exists.\n"
2774 			   " Hint: Remove existing event by 'perf probe -d'\n"
2775 			   "       or force duplicates by 'perf probe -f'\n"
2776 			   "       or set 'force=yes' in BPF source.\n",
2777 			   buf);
2778 		ret = -EEXIST;
2779 		goto out;
2780 	}
2781 
2782 	/* Try to add suffix */
2783 	for (i = 1; i < MAX_EVENT_INDEX; i++) {
2784 		ret = e_snprintf(buf, len, "%s_%d", nbase, i);
2785 		if (ret < 0) {
2786 			pr_warning("Add suffix failed: %d; the event name '%s' is too long\n"
2787 				   "  Hint: Set a shorter event with syntax \"EVENT=PROBEDEF\"\n"
2788 				   "        EVENT: Event name (max length: %d bytes).\n",
2789 				   ret, nbase, MAX_EVENT_NAME_LEN);
2790 			goto out;
2791 		}
2792 		if (!strlist__has_entry(namelist, buf))
2793 			break;
2794 	}
2795 	if (i == MAX_EVENT_INDEX) {
2796 		pr_warning("Too many events are on the same function.\n");
2797 		ret = -ERANGE;
2798 	}
2799 
2800 out:
2801 	free(nbase);
2802 
2803 	/* Final validation */
2804 	if (ret >= 0 && !is_c_func_name(buf)) {
2805 		pr_warning("Internal error: \"%s\" is an invalid event name.\n",
2806 			   buf);
2807 		ret = -EINVAL;
2808 	}
2809 
2810 	return ret;
2811 }
2812 
2813 /* Warn if the current kernel's uprobe implementation is old */
2814 static void warn_uprobe_event_compat(struct probe_trace_event *tev)
2815 {
2816 	int i;
2817 	char *buf = synthesize_probe_trace_command(tev);
2818 	struct probe_trace_point *tp = &tev->point;
2819 
2820 	if (tp->ref_ctr_offset && !uprobe_ref_ctr_is_supported()) {
2821 		pr_warning("A semaphore is associated with %s:%s and "
2822 			   "seems your kernel doesn't support it.\n",
2823 			   tev->group, tev->event);
2824 	}
2825 
2826 	/* Old uprobe event doesn't support memory dereference */
2827 	if (!tev->uprobes || tev->nargs == 0 || !buf)
2828 		goto out;
2829 
2830 	for (i = 0; i < tev->nargs; i++) {
2831 		if (strchr(tev->args[i].value, '@')) {
2832 			pr_warning("%s accesses a variable by symbol name, but that is not supported for user application probe.\n",
2833 				   tev->args[i].value);
2834 			break;
2835 		}
2836 		if (strglobmatch(tev->args[i].value, "[$+-]*")) {
2837 			pr_warning("Please upgrade your kernel to at least 3.14 to have access to feature %s\n",
2838 				   tev->args[i].value);
2839 			break;
2840 		}
2841 	}
2842 out:
2843 	free(buf);
2844 }
2845 
2846 /* Set new name from original perf_probe_event and namelist */
2847 static int probe_trace_event__set_name(struct probe_trace_event *tev,
2848 				       struct perf_probe_event *pev,
2849 				       struct strlist *namelist,
2850 				       bool allow_suffix)
2851 {
2852 	const char *event, *group;
2853 	char buf[MAX_EVENT_NAME_LEN];
2854 	int ret;
2855 
2856 	/* If probe_event or trace_event already have the name, reuse it */
2857 	if (pev->event && !pev->sdt)
2858 		event = pev->event;
2859 	else if (tev->event)
2860 		event = tev->event;
2861 	else {
2862 		/* Or generate new one from probe point */
2863 		if (pev->point.function &&
2864 			(strncmp(pev->point.function, "0x", 2) != 0) &&
2865 			!strisglob(pev->point.function))
2866 			event = pev->point.function;
2867 		else
2868 			event = tev->point.realname;
2869 	}
2870 	if (pev->group && !pev->sdt)
2871 		group = pev->group;
2872 	else if (tev->group)
2873 		group = tev->group;
2874 	else
2875 		group = PERFPROBE_GROUP;
2876 
2877 	if (strlen(group) >= MAX_EVENT_NAME_LEN) {
2878 		pr_err("Probe group string='%s' is too long (>= %d bytes)\n",
2879 			group, MAX_EVENT_NAME_LEN);
2880 		return -ENOMEM;
2881 	}
2882 
2883 	/* Get an unused new event name */
2884 	ret = get_new_event_name(buf, sizeof(buf), event, namelist,
2885 				 tev->point.retprobe, allow_suffix);
2886 	if (ret < 0)
2887 		return ret;
2888 
2889 	event = buf;
2890 
2891 	tev->event = strdup(event);
2892 	tev->group = strdup(group);
2893 	if (tev->event == NULL || tev->group == NULL)
2894 		return -ENOMEM;
2895 
2896 	/*
2897 	 * Add new event name to namelist if multiprobe event is NOT
2898 	 * supported, since we have to use new event name for following
2899 	 * probes in that case.
2900 	 */
2901 	if (!multiprobe_event_is_supported())
2902 		strlist__add(namelist, event);
2903 	return 0;
2904 }
2905 
2906 static int __open_probe_file_and_namelist(bool uprobe,
2907 					  struct strlist **namelist)
2908 {
2909 	int fd;
2910 
2911 	fd = probe_file__open(PF_FL_RW | (uprobe ? PF_FL_UPROBE : 0));
2912 	if (fd < 0)
2913 		return fd;
2914 
2915 	/* Get current event names */
2916 	*namelist = probe_file__get_namelist(fd);
2917 	if (!(*namelist)) {
2918 		pr_debug("Failed to get current event list.\n");
2919 		close(fd);
2920 		return -ENOMEM;
2921 	}
2922 	return fd;
2923 }
2924 
2925 static int __add_probe_trace_events(struct perf_probe_event *pev,
2926 				     struct probe_trace_event *tevs,
2927 				     int ntevs, bool allow_suffix)
2928 {
2929 	int i, fd[2] = {-1, -1}, up, ret;
2930 	struct probe_trace_event *tev = NULL;
2931 	struct probe_cache *cache = NULL;
2932 	struct strlist *namelist[2] = {NULL, NULL};
2933 	struct nscookie nsc;
2934 
2935 	up = pev->uprobes ? 1 : 0;
2936 	fd[up] = __open_probe_file_and_namelist(up, &namelist[up]);
2937 	if (fd[up] < 0)
2938 		return fd[up];
2939 
2940 	ret = 0;
2941 	for (i = 0; i < ntevs; i++) {
2942 		tev = &tevs[i];
2943 		up = tev->uprobes ? 1 : 0;
2944 		if (fd[up] == -1) {	/* Open the kprobe/uprobe_events */
2945 			fd[up] = __open_probe_file_and_namelist(up,
2946 								&namelist[up]);
2947 			if (fd[up] < 0)
2948 				goto close_out;
2949 		}
2950 		/* Skip if the symbol is out of .text or blacklisted */
2951 		if (!tev->point.symbol && !pev->uprobes)
2952 			continue;
2953 
2954 		/* Set new name for tev (and update namelist) */
2955 		ret = probe_trace_event__set_name(tev, pev, namelist[up],
2956 						  allow_suffix);
2957 		if (ret < 0)
2958 			break;
2959 
2960 		nsinfo__mountns_enter(pev->nsi, &nsc);
2961 		ret = probe_file__add_event(fd[up], tev);
2962 		nsinfo__mountns_exit(&nsc);
2963 		if (ret < 0)
2964 			break;
2965 
2966 		/*
2967 		 * Probes after the first probe which comes from same
2968 		 * user input are always allowed to add suffix, because
2969 		 * there might be several addresses corresponding to
2970 		 * one code line.
2971 		 */
2972 		allow_suffix = true;
2973 	}
2974 	if (ret == -EINVAL && pev->uprobes)
2975 		warn_uprobe_event_compat(tev);
2976 	if (ret == 0 && probe_conf.cache) {
2977 		cache = probe_cache__new(pev->target, pev->nsi);
2978 		if (!cache ||
2979 		    probe_cache__add_entry(cache, pev, tevs, ntevs) < 0 ||
2980 		    probe_cache__commit(cache) < 0)
2981 			pr_warning("Failed to add event to probe cache\n");
2982 		probe_cache__delete(cache);
2983 	}
2984 
2985 close_out:
2986 	for (up = 0; up < 2; up++) {
2987 		strlist__delete(namelist[up]);
2988 		if (fd[up] >= 0)
2989 			close(fd[up]);
2990 	}
2991 	return ret;
2992 }
2993 
2994 static int find_probe_functions(struct map *map, char *name,
2995 				struct symbol **syms)
2996 {
2997 	int found = 0;
2998 	struct symbol *sym;
2999 	struct rb_node *tmp;
3000 	const char *norm, *ver;
3001 	char *buf = NULL;
3002 	bool cut_version = true;
3003 
3004 	if (map__load(map) < 0)
3005 		return -EACCES;	/* Possible permission error to load symbols */
3006 
3007 	/* If user gives a version, don't cut off the version from symbols */
3008 	if (strchr(name, '@'))
3009 		cut_version = false;
3010 
3011 	map__for_each_symbol(map, sym, tmp) {
3012 		norm = arch__normalize_symbol_name(sym->name);
3013 		if (!norm)
3014 			continue;
3015 
3016 		if (cut_version) {
3017 			/* We don't care about default symbol or not */
3018 			ver = strchr(norm, '@');
3019 			if (ver) {
3020 				buf = strndup(norm, ver - norm);
3021 				if (!buf)
3022 					return -ENOMEM;
3023 				norm = buf;
3024 			}
3025 		}
3026 
3027 		if (strglobmatch(norm, name)) {
3028 			found++;
3029 			if (syms && found < probe_conf.max_probes)
3030 				syms[found - 1] = sym;
3031 		}
3032 		if (buf)
3033 			zfree(&buf);
3034 	}
3035 
3036 	return found;
3037 }
3038 
3039 void __weak arch__fix_tev_from_maps(struct perf_probe_event *pev __maybe_unused,
3040 				struct probe_trace_event *tev __maybe_unused,
3041 				struct map *map __maybe_unused,
3042 				struct symbol *sym __maybe_unused) { }
3043 
3044 
3045 static void pr_kallsyms_access_error(void)
3046 {
3047 	pr_err("Please ensure you can read the /proc/kallsyms symbol addresses.\n"
3048 	       "If /proc/sys/kernel/kptr_restrict is '2', you can not read\n"
3049 	       "kernel symbol addresses even if you are a superuser. Please change\n"
3050 	       "it to '1'. If kptr_restrict is '1', the superuser can read the\n"
3051 	       "symbol addresses.\n"
3052 	       "In that case, please run this command again with sudo.\n");
3053 }
3054 
3055 /*
3056  * Find probe function addresses from map.
3057  * Return an error or the number of found probe_trace_event
3058  */
3059 static int find_probe_trace_events_from_map(struct perf_probe_event *pev,
3060 					    struct probe_trace_event **tevs)
3061 {
3062 	struct map *map = NULL;
3063 	struct ref_reloc_sym *reloc_sym = NULL;
3064 	struct symbol *sym;
3065 	struct symbol **syms = NULL;
3066 	struct probe_trace_event *tev;
3067 	struct perf_probe_point *pp = &pev->point;
3068 	struct probe_trace_point *tp;
3069 	int num_matched_functions;
3070 	int ret, i, j, skipped = 0;
3071 	char *mod_name;
3072 
3073 	map = get_target_map(pev->target, pev->nsi, pev->uprobes);
3074 	if (!map) {
3075 		ret = -EINVAL;
3076 		goto out;
3077 	}
3078 
3079 	syms = malloc(sizeof(struct symbol *) * probe_conf.max_probes);
3080 	if (!syms) {
3081 		ret = -ENOMEM;
3082 		goto out;
3083 	}
3084 
3085 	/*
3086 	 * Load matched symbols: Since the different local symbols may have
3087 	 * same name but different addresses, this lists all the symbols.
3088 	 */
3089 	num_matched_functions = find_probe_functions(map, pp->function, syms);
3090 	if (num_matched_functions <= 0) {
3091 		if (num_matched_functions == -EACCES) {
3092 			pr_err("Failed to load symbols from %s\n",
3093 			       pev->target ?: "/proc/kallsyms");
3094 			if (pev->target)
3095 				pr_err("Please ensure the file is not stripped.\n");
3096 			else
3097 				pr_kallsyms_access_error();
3098 		} else
3099 			pr_err("Failed to find symbol %s in %s\n", pp->function,
3100 				pev->target ? : "kernel");
3101 		ret = -ENOENT;
3102 		goto out;
3103 	} else if (num_matched_functions > probe_conf.max_probes) {
3104 		pr_err("Too many functions matched in %s\n",
3105 			pev->target ? : "kernel");
3106 		ret = -E2BIG;
3107 		goto out;
3108 	}
3109 
3110 	/* Note that the symbols in the kmodule are not relocated */
3111 	if (!pev->uprobes && !pev->target &&
3112 			(!pp->retprobe || kretprobe_offset_is_supported())) {
3113 		reloc_sym = kernel_get_ref_reloc_sym(NULL);
3114 		if (!reloc_sym) {
3115 			pr_warning("Relocated base symbol is not found! "
3116 				   "Check /proc/sys/kernel/kptr_restrict\n"
3117 				   "and /proc/sys/kernel/perf_event_paranoid. "
3118 				   "Or run as privileged perf user.\n\n");
3119 			ret = -EINVAL;
3120 			goto out;
3121 		}
3122 	}
3123 
3124 	/* Setup result trace-probe-events */
3125 	*tevs = zalloc(sizeof(*tev) * num_matched_functions);
3126 	if (!*tevs) {
3127 		ret = -ENOMEM;
3128 		goto out;
3129 	}
3130 
3131 	ret = 0;
3132 
3133 	for (j = 0; j < num_matched_functions; j++) {
3134 		sym = syms[j];
3135 
3136 		if (sym->type != STT_FUNC)
3137 			continue;
3138 
3139 		/* There can be duplicated symbols in the map */
3140 		for (i = 0; i < j; i++)
3141 			if (sym->start == syms[i]->start) {
3142 				pr_debug("Found duplicated symbol %s @ %" PRIx64 "\n",
3143 					 sym->name, sym->start);
3144 				break;
3145 			}
3146 		if (i != j)
3147 			continue;
3148 
3149 		tev = (*tevs) + ret;
3150 		tp = &tev->point;
3151 		if (ret == num_matched_functions) {
3152 			pr_warning("Too many symbols are listed. Skip it.\n");
3153 			break;
3154 		}
3155 		ret++;
3156 
3157 		if (pp->offset > sym->end - sym->start) {
3158 			pr_warning("Offset %ld is bigger than the size of %s\n",
3159 				   pp->offset, sym->name);
3160 			ret = -ENOENT;
3161 			goto err_out;
3162 		}
3163 		/* Add one probe point */
3164 		tp->address = map__unmap_ip(map, sym->start) + pp->offset;
3165 
3166 		/* Check the kprobe (not in module) is within .text  */
3167 		if (!pev->uprobes && !pev->target &&
3168 		    kprobe_warn_out_range(sym->name, tp->address)) {
3169 			tp->symbol = NULL;	/* Skip it */
3170 			skipped++;
3171 		} else if (reloc_sym) {
3172 			tp->symbol = strdup_or_goto(reloc_sym->name, nomem_out);
3173 			tp->offset = tp->address - reloc_sym->addr;
3174 		} else {
3175 			tp->symbol = strdup_or_goto(sym->name, nomem_out);
3176 			tp->offset = pp->offset;
3177 		}
3178 		tp->realname = strdup_or_goto(sym->name, nomem_out);
3179 
3180 		tp->retprobe = pp->retprobe;
3181 		if (pev->target) {
3182 			if (pev->uprobes) {
3183 				tev->point.module = strdup_or_goto(pev->target,
3184 								   nomem_out);
3185 			} else {
3186 				mod_name = find_module_name(pev->target);
3187 				tev->point.module =
3188 					strdup(mod_name ? mod_name : pev->target);
3189 				free(mod_name);
3190 				if (!tev->point.module)
3191 					goto nomem_out;
3192 			}
3193 		}
3194 		tev->uprobes = pev->uprobes;
3195 		tev->nargs = pev->nargs;
3196 		if (tev->nargs) {
3197 			tev->args = zalloc(sizeof(struct probe_trace_arg) *
3198 					   tev->nargs);
3199 			if (tev->args == NULL)
3200 				goto nomem_out;
3201 		}
3202 		for (i = 0; i < tev->nargs; i++) {
3203 			if (pev->args[i].name)
3204 				tev->args[i].name =
3205 					strdup_or_goto(pev->args[i].name,
3206 							nomem_out);
3207 
3208 			tev->args[i].value = strdup_or_goto(pev->args[i].var,
3209 							    nomem_out);
3210 			if (pev->args[i].type)
3211 				tev->args[i].type =
3212 					strdup_or_goto(pev->args[i].type,
3213 							nomem_out);
3214 		}
3215 		arch__fix_tev_from_maps(pev, tev, map, sym);
3216 	}
3217 	if (ret == skipped) {
3218 		ret = -ENOENT;
3219 		goto err_out;
3220 	}
3221 
3222 out:
3223 	map__put(map);
3224 	free(syms);
3225 	return ret;
3226 
3227 nomem_out:
3228 	ret = -ENOMEM;
3229 err_out:
3230 	clear_probe_trace_events(*tevs, num_matched_functions);
3231 	zfree(tevs);
3232 	goto out;
3233 }
3234 
3235 static int try_to_find_absolute_address(struct perf_probe_event *pev,
3236 					struct probe_trace_event **tevs)
3237 {
3238 	struct perf_probe_point *pp = &pev->point;
3239 	struct probe_trace_event *tev;
3240 	struct probe_trace_point *tp;
3241 	int i, err;
3242 
3243 	if (!(pev->point.function && !strncmp(pev->point.function, "0x", 2)))
3244 		return -EINVAL;
3245 	if (perf_probe_event_need_dwarf(pev))
3246 		return -EINVAL;
3247 
3248 	/*
3249 	 * This is 'perf probe /lib/libc.so 0xabcd'. Try to probe at
3250 	 * absolute address.
3251 	 *
3252 	 * Only one tev can be generated by this.
3253 	 */
3254 	*tevs = zalloc(sizeof(*tev));
3255 	if (!*tevs)
3256 		return -ENOMEM;
3257 
3258 	tev = *tevs;
3259 	tp = &tev->point;
3260 
3261 	/*
3262 	 * Don't use tp->offset, use address directly, because
3263 	 * in synthesize_probe_trace_command() address cannot be
3264 	 * zero.
3265 	 */
3266 	tp->address = pev->point.abs_address;
3267 	tp->retprobe = pp->retprobe;
3268 	tev->uprobes = pev->uprobes;
3269 
3270 	err = -ENOMEM;
3271 	/*
3272 	 * Give it a '0x' leading symbol name.
3273 	 * In __add_probe_trace_events, a NULL symbol is interpreted as
3274 	 * invalid.
3275 	 */
3276 	if (asprintf(&tp->symbol, "0x%" PRIx64, tp->address) < 0)
3277 		goto errout;
3278 
3279 	/* For kprobe, check range */
3280 	if ((!tev->uprobes) &&
3281 	    (kprobe_warn_out_range(tev->point.symbol,
3282 				   tev->point.address))) {
3283 		err = -EACCES;
3284 		goto errout;
3285 	}
3286 
3287 	if (asprintf(&tp->realname, "abs_%" PRIx64, tp->address) < 0)
3288 		goto errout;
3289 
3290 	if (pev->target) {
3291 		tp->module = strdup(pev->target);
3292 		if (!tp->module)
3293 			goto errout;
3294 	}
3295 
3296 	if (tev->group) {
3297 		tev->group = strdup(pev->group);
3298 		if (!tev->group)
3299 			goto errout;
3300 	}
3301 
3302 	if (pev->event) {
3303 		tev->event = strdup(pev->event);
3304 		if (!tev->event)
3305 			goto errout;
3306 	}
3307 
3308 	tev->nargs = pev->nargs;
3309 	tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
3310 	if (!tev->args)
3311 		goto errout;
3312 
3313 	for (i = 0; i < tev->nargs; i++)
3314 		copy_to_probe_trace_arg(&tev->args[i], &pev->args[i]);
3315 
3316 	return 1;
3317 
3318 errout:
3319 	clear_probe_trace_events(*tevs, 1);
3320 	*tevs = NULL;
3321 	return err;
3322 }
3323 
3324 /* Concatenate two arrays */
3325 static void *memcat(void *a, size_t sz_a, void *b, size_t sz_b)
3326 {
3327 	void *ret;
3328 
3329 	ret = malloc(sz_a + sz_b);
3330 	if (ret) {
3331 		memcpy(ret, a, sz_a);
3332 		memcpy(ret + sz_a, b, sz_b);
3333 	}
3334 	return ret;
3335 }
3336 
3337 static int
3338 concat_probe_trace_events(struct probe_trace_event **tevs, int *ntevs,
3339 			  struct probe_trace_event **tevs2, int ntevs2)
3340 {
3341 	struct probe_trace_event *new_tevs;
3342 	int ret = 0;
3343 
3344 	if (*ntevs == 0) {
3345 		*tevs = *tevs2;
3346 		*ntevs = ntevs2;
3347 		*tevs2 = NULL;
3348 		return 0;
3349 	}
3350 
3351 	if (*ntevs + ntevs2 > probe_conf.max_probes)
3352 		ret = -E2BIG;
3353 	else {
3354 		/* Concatenate the array of probe_trace_event */
3355 		new_tevs = memcat(*tevs, (*ntevs) * sizeof(**tevs),
3356 				  *tevs2, ntevs2 * sizeof(**tevs2));
3357 		if (!new_tevs)
3358 			ret = -ENOMEM;
3359 		else {
3360 			free(*tevs);
3361 			*tevs = new_tevs;
3362 			*ntevs += ntevs2;
3363 		}
3364 	}
3365 	if (ret < 0)
3366 		clear_probe_trace_events(*tevs2, ntevs2);
3367 	zfree(tevs2);
3368 
3369 	return ret;
3370 }
3371 
3372 /*
3373  * Try to find probe_trace_event from given probe caches. Return the number
3374  * of cached events found, if an error occurs return the error.
3375  */
3376 static int find_cached_events(struct perf_probe_event *pev,
3377 			      struct probe_trace_event **tevs,
3378 			      const char *target)
3379 {
3380 	struct probe_cache *cache;
3381 	struct probe_cache_entry *entry;
3382 	struct probe_trace_event *tmp_tevs = NULL;
3383 	int ntevs = 0;
3384 	int ret = 0;
3385 
3386 	cache = probe_cache__new(target, pev->nsi);
3387 	/* Return 0 ("not found") if the target has no probe cache. */
3388 	if (!cache)
3389 		return 0;
3390 
3391 	for_each_probe_cache_entry(entry, cache) {
3392 		/* Skip the cache entry which has no name */
3393 		if (!entry->pev.event || !entry->pev.group)
3394 			continue;
3395 		if ((!pev->group || strglobmatch(entry->pev.group, pev->group)) &&
3396 		    strglobmatch(entry->pev.event, pev->event)) {
3397 			ret = probe_cache_entry__get_event(entry, &tmp_tevs);
3398 			if (ret > 0)
3399 				ret = concat_probe_trace_events(tevs, &ntevs,
3400 								&tmp_tevs, ret);
3401 			if (ret < 0)
3402 				break;
3403 		}
3404 	}
3405 	probe_cache__delete(cache);
3406 	if (ret < 0) {
3407 		clear_probe_trace_events(*tevs, ntevs);
3408 		zfree(tevs);
3409 	} else {
3410 		ret = ntevs;
3411 		if (ntevs > 0 && target && target[0] == '/')
3412 			pev->uprobes = true;
3413 	}
3414 
3415 	return ret;
3416 }
3417 
3418 /* Try to find probe_trace_event from all probe caches */
3419 static int find_cached_events_all(struct perf_probe_event *pev,
3420 				   struct probe_trace_event **tevs)
3421 {
3422 	struct probe_trace_event *tmp_tevs = NULL;
3423 	struct strlist *bidlist;
3424 	struct str_node *nd;
3425 	char *pathname;
3426 	int ntevs = 0;
3427 	int ret;
3428 
3429 	/* Get the buildid list of all valid caches */
3430 	bidlist = build_id_cache__list_all(true);
3431 	if (!bidlist) {
3432 		ret = -errno;
3433 		pr_debug("Failed to get buildids: %d\n", ret);
3434 		return ret;
3435 	}
3436 
3437 	ret = 0;
3438 	strlist__for_each_entry(nd, bidlist) {
3439 		pathname = build_id_cache__origname(nd->s);
3440 		ret = find_cached_events(pev, &tmp_tevs, pathname);
3441 		/* In the case of cnt == 0, we just skip it */
3442 		if (ret > 0)
3443 			ret = concat_probe_trace_events(tevs, &ntevs,
3444 							&tmp_tevs, ret);
3445 		free(pathname);
3446 		if (ret < 0)
3447 			break;
3448 	}
3449 	strlist__delete(bidlist);
3450 
3451 	if (ret < 0) {
3452 		clear_probe_trace_events(*tevs, ntevs);
3453 		zfree(tevs);
3454 	} else
3455 		ret = ntevs;
3456 
3457 	return ret;
3458 }
3459 
3460 static int find_probe_trace_events_from_cache(struct perf_probe_event *pev,
3461 					      struct probe_trace_event **tevs)
3462 {
3463 	struct probe_cache *cache;
3464 	struct probe_cache_entry *entry;
3465 	struct probe_trace_event *tev;
3466 	struct str_node *node;
3467 	int ret, i;
3468 
3469 	if (pev->sdt) {
3470 		/* For SDT/cached events, we use special search functions */
3471 		if (!pev->target)
3472 			return find_cached_events_all(pev, tevs);
3473 		else
3474 			return find_cached_events(pev, tevs, pev->target);
3475 	}
3476 	cache = probe_cache__new(pev->target, pev->nsi);
3477 	if (!cache)
3478 		return 0;
3479 
3480 	entry = probe_cache__find(cache, pev);
3481 	if (!entry) {
3482 		/* SDT must be in the cache */
3483 		ret = pev->sdt ? -ENOENT : 0;
3484 		goto out;
3485 	}
3486 
3487 	ret = strlist__nr_entries(entry->tevlist);
3488 	if (ret > probe_conf.max_probes) {
3489 		pr_debug("Too many entries matched in the cache of %s\n",
3490 			 pev->target ? : "kernel");
3491 		ret = -E2BIG;
3492 		goto out;
3493 	}
3494 
3495 	*tevs = zalloc(ret * sizeof(*tev));
3496 	if (!*tevs) {
3497 		ret = -ENOMEM;
3498 		goto out;
3499 	}
3500 
3501 	i = 0;
3502 	strlist__for_each_entry(node, entry->tevlist) {
3503 		tev = &(*tevs)[i++];
3504 		ret = parse_probe_trace_command(node->s, tev);
3505 		if (ret < 0)
3506 			goto out;
3507 		/* Set the uprobes attribute as same as original */
3508 		tev->uprobes = pev->uprobes;
3509 	}
3510 	ret = i;
3511 
3512 out:
3513 	probe_cache__delete(cache);
3514 	return ret;
3515 }
3516 
3517 static int convert_to_probe_trace_events(struct perf_probe_event *pev,
3518 					 struct probe_trace_event **tevs)
3519 {
3520 	int ret;
3521 
3522 	if (!pev->group && !pev->sdt) {
3523 		/* Set group name if not given */
3524 		if (!pev->uprobes) {
3525 			pev->group = strdup(PERFPROBE_GROUP);
3526 			ret = pev->group ? 0 : -ENOMEM;
3527 		} else
3528 			ret = convert_exec_to_group(pev->target, &pev->group);
3529 		if (ret != 0) {
3530 			pr_warning("Failed to make a group name.\n");
3531 			return ret;
3532 		}
3533 	}
3534 
3535 	ret = try_to_find_absolute_address(pev, tevs);
3536 	if (ret > 0)
3537 		return ret;
3538 
3539 	/* At first, we need to lookup cache entry */
3540 	ret = find_probe_trace_events_from_cache(pev, tevs);
3541 	if (ret > 0 || pev->sdt)	/* SDT can be found only in the cache */
3542 		return ret == 0 ? -ENOENT : ret; /* Found in probe cache */
3543 
3544 	/* Convert perf_probe_event with debuginfo */
3545 	ret = try_to_find_probe_trace_events(pev, tevs);
3546 	if (ret != 0)
3547 		return ret;	/* Found in debuginfo or got an error */
3548 
3549 	return find_probe_trace_events_from_map(pev, tevs);
3550 }
3551 
3552 int convert_perf_probe_events(struct perf_probe_event *pevs, int npevs)
3553 {
3554 	int i, ret;
3555 
3556 	/* Loop 1: convert all events */
3557 	for (i = 0; i < npevs; i++) {
3558 		/* Init kprobe blacklist if needed */
3559 		if (!pevs[i].uprobes)
3560 			kprobe_blacklist__init();
3561 		/* Convert with or without debuginfo */
3562 		ret  = convert_to_probe_trace_events(&pevs[i], &pevs[i].tevs);
3563 		if (ret < 0)
3564 			return ret;
3565 		pevs[i].ntevs = ret;
3566 	}
3567 	/* This just release blacklist only if allocated */
3568 	kprobe_blacklist__release();
3569 
3570 	return 0;
3571 }
3572 
3573 static int show_probe_trace_event(struct probe_trace_event *tev)
3574 {
3575 	char *buf = synthesize_probe_trace_command(tev);
3576 
3577 	if (!buf) {
3578 		pr_debug("Failed to synthesize probe trace event.\n");
3579 		return -EINVAL;
3580 	}
3581 
3582 	/* Showing definition always go stdout */
3583 	printf("%s\n", buf);
3584 	free(buf);
3585 
3586 	return 0;
3587 }
3588 
3589 int show_probe_trace_events(struct perf_probe_event *pevs, int npevs)
3590 {
3591 	struct strlist *namelist = strlist__new(NULL, NULL);
3592 	struct probe_trace_event *tev;
3593 	struct perf_probe_event *pev;
3594 	int i, j, ret = 0;
3595 
3596 	if (!namelist)
3597 		return -ENOMEM;
3598 
3599 	for (j = 0; j < npevs && !ret; j++) {
3600 		pev = &pevs[j];
3601 		for (i = 0; i < pev->ntevs && !ret; i++) {
3602 			tev = &pev->tevs[i];
3603 			/* Skip if the symbol is out of .text or blacklisted */
3604 			if (!tev->point.symbol && !pev->uprobes)
3605 				continue;
3606 
3607 			/* Set new name for tev (and update namelist) */
3608 			ret = probe_trace_event__set_name(tev, pev,
3609 							  namelist, true);
3610 			if (!ret)
3611 				ret = show_probe_trace_event(tev);
3612 		}
3613 	}
3614 	strlist__delete(namelist);
3615 
3616 	return ret;
3617 }
3618 
3619 static int show_bootconfig_event(struct probe_trace_event *tev)
3620 {
3621 	struct probe_trace_point *tp = &tev->point;
3622 	struct strbuf buf;
3623 	char *ret = NULL;
3624 	int err;
3625 
3626 	if (strbuf_init(&buf, 32) < 0)
3627 		return -ENOMEM;
3628 
3629 	err = synthesize_kprobe_trace_def(tp, &buf);
3630 	if (err >= 0)
3631 		err = synthesize_probe_trace_args(tev, &buf);
3632 	if (err >= 0)
3633 		ret = strbuf_detach(&buf, NULL);
3634 	strbuf_release(&buf);
3635 
3636 	if (ret) {
3637 		printf("'%s'", ret);
3638 		free(ret);
3639 	}
3640 
3641 	return err;
3642 }
3643 
3644 int show_bootconfig_events(struct perf_probe_event *pevs, int npevs)
3645 {
3646 	struct strlist *namelist = strlist__new(NULL, NULL);
3647 	struct probe_trace_event *tev;
3648 	struct perf_probe_event *pev;
3649 	char *cur_name = NULL;
3650 	int i, j, ret = 0;
3651 
3652 	if (!namelist)
3653 		return -ENOMEM;
3654 
3655 	for (j = 0; j < npevs && !ret; j++) {
3656 		pev = &pevs[j];
3657 		if (pev->group && strcmp(pev->group, "probe"))
3658 			pr_warning("WARN: Group name %s is ignored\n", pev->group);
3659 		if (pev->uprobes) {
3660 			pr_warning("ERROR: Bootconfig doesn't support uprobes\n");
3661 			ret = -EINVAL;
3662 			break;
3663 		}
3664 		for (i = 0; i < pev->ntevs && !ret; i++) {
3665 			tev = &pev->tevs[i];
3666 			/* Skip if the symbol is out of .text or blacklisted */
3667 			if (!tev->point.symbol && !pev->uprobes)
3668 				continue;
3669 
3670 			/* Set new name for tev (and update namelist) */
3671 			ret = probe_trace_event__set_name(tev, pev,
3672 							  namelist, true);
3673 			if (ret)
3674 				break;
3675 
3676 			if (!cur_name || strcmp(cur_name, tev->event)) {
3677 				printf("%sftrace.event.kprobes.%s.probe = ",
3678 					cur_name ? "\n" : "", tev->event);
3679 				cur_name = tev->event;
3680 			} else
3681 				printf(", ");
3682 			ret = show_bootconfig_event(tev);
3683 		}
3684 	}
3685 	printf("\n");
3686 	strlist__delete(namelist);
3687 
3688 	return ret;
3689 }
3690 
3691 int apply_perf_probe_events(struct perf_probe_event *pevs, int npevs)
3692 {
3693 	int i, ret = 0;
3694 
3695 	/* Loop 2: add all events */
3696 	for (i = 0; i < npevs; i++) {
3697 		ret = __add_probe_trace_events(&pevs[i], pevs[i].tevs,
3698 					       pevs[i].ntevs,
3699 					       probe_conf.force_add);
3700 		if (ret < 0)
3701 			break;
3702 	}
3703 	return ret;
3704 }
3705 
3706 void cleanup_perf_probe_events(struct perf_probe_event *pevs, int npevs)
3707 {
3708 	int i, j;
3709 	struct perf_probe_event *pev;
3710 
3711 	/* Loop 3: cleanup and free trace events  */
3712 	for (i = 0; i < npevs; i++) {
3713 		pev = &pevs[i];
3714 		for (j = 0; j < pevs[i].ntevs; j++)
3715 			clear_probe_trace_event(&pevs[i].tevs[j]);
3716 		zfree(&pevs[i].tevs);
3717 		pevs[i].ntevs = 0;
3718 		nsinfo__zput(pev->nsi);
3719 		clear_perf_probe_event(&pevs[i]);
3720 	}
3721 }
3722 
3723 int del_perf_probe_events(struct strfilter *filter)
3724 {
3725 	int ret, ret2, ufd = -1, kfd = -1;
3726 	char *str = strfilter__string(filter);
3727 
3728 	if (!str)
3729 		return -EINVAL;
3730 
3731 	/* Get current event names */
3732 	ret = probe_file__open_both(&kfd, &ufd, PF_FL_RW);
3733 	if (ret < 0)
3734 		goto out;
3735 
3736 	ret = probe_file__del_events(kfd, filter);
3737 	if (ret < 0 && ret != -ENOENT)
3738 		goto error;
3739 
3740 	ret2 = probe_file__del_events(ufd, filter);
3741 	if (ret2 < 0 && ret2 != -ENOENT) {
3742 		ret = ret2;
3743 		goto error;
3744 	}
3745 	ret = 0;
3746 
3747 error:
3748 	if (kfd >= 0)
3749 		close(kfd);
3750 	if (ufd >= 0)
3751 		close(ufd);
3752 out:
3753 	free(str);
3754 
3755 	return ret;
3756 }
3757 
3758 int show_available_funcs(const char *target, struct nsinfo *nsi,
3759 			 struct strfilter *_filter, bool user)
3760 {
3761 	struct map *map;
3762 	struct dso *dso;
3763 	int ret;
3764 
3765 	ret = init_probe_symbol_maps(user);
3766 	if (ret < 0)
3767 		return ret;
3768 
3769 	/* Get a symbol map */
3770 	map = get_target_map(target, nsi, user);
3771 	if (!map) {
3772 		pr_err("Failed to get a map for %s\n", (target) ? : "kernel");
3773 		return -EINVAL;
3774 	}
3775 
3776 	ret = map__load(map);
3777 	if (ret) {
3778 		if (ret == -2) {
3779 			char *str = strfilter__string(_filter);
3780 			pr_err("Failed to find symbols matched to \"%s\"\n",
3781 			       str);
3782 			free(str);
3783 		} else
3784 			pr_err("Failed to load symbols in %s\n",
3785 			       (target) ? : "kernel");
3786 		goto end;
3787 	}
3788 	dso = map__dso(map);
3789 	dso__sort_by_name(dso);
3790 
3791 	/* Show all (filtered) symbols */
3792 	setup_pager();
3793 
3794 	for (size_t i = 0; i < dso__symbol_names_len(dso); i++) {
3795 		struct symbol *pos = dso__symbol_names(dso)[i];
3796 
3797 		if (strfilter__compare(_filter, pos->name))
3798 			printf("%s\n", pos->name);
3799 	}
3800 end:
3801 	map__put(map);
3802 	exit_probe_symbol_maps();
3803 
3804 	return ret;
3805 }
3806 
3807 int copy_to_probe_trace_arg(struct probe_trace_arg *tvar,
3808 			    struct perf_probe_arg *pvar)
3809 {
3810 	tvar->value = strdup(pvar->var);
3811 	if (tvar->value == NULL)
3812 		return -ENOMEM;
3813 	if (pvar->type) {
3814 		tvar->type = strdup(pvar->type);
3815 		if (tvar->type == NULL)
3816 			return -ENOMEM;
3817 	}
3818 	if (pvar->name) {
3819 		tvar->name = strdup(pvar->name);
3820 		if (tvar->name == NULL)
3821 			return -ENOMEM;
3822 	} else
3823 		tvar->name = NULL;
3824 	return 0;
3825 }
3826