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