1 /*
2 * probe-event.c : perf-probe definition to probe_events format converter
3 *
4 * Written by Masami Hiramatsu <mhiramat@redhat.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19 *
20 */
21
22 #define _GNU_SOURCE
23 #include <sys/utsname.h>
24 #include <sys/types.h>
25 #include <sys/stat.h>
26 #include <fcntl.h>
27 #include <errno.h>
28 #include <stdio.h>
29 #include <unistd.h>
30 #include <stdlib.h>
31 #include <string.h>
32 #include <stdarg.h>
33 #include <limits.h>
34 #include <elf.h>
35
36 #undef _GNU_SOURCE
37 #include "util.h"
38 #include "event.h"
39 #include "string.h"
40 #include "strlist.h"
41 #include "debug.h"
42 #include "cache.h"
43 #include "color.h"
44 #include "symbol.h"
45 #include "thread.h"
46 #include "debugfs.h"
47 #include "trace-event.h" /* For __unused */
48 #include "probe-event.h"
49 #include "probe-finder.h"
50
51 #define MAX_CMDLEN 256
52 #define MAX_PROBE_ARGS 128
53 #define PERFPROBE_GROUP "probe"
54
55 bool probe_event_dry_run; /* Dry run flag */
56
57 #define semantic_error(msg ...) pr_err("Semantic error :" msg)
58
59 /* If there is no space to write, returns -E2BIG. */
60 static int e_snprintf(char *str, size_t size, const char *format, ...)
61 __attribute__((format(printf, 3, 4)));
62
e_snprintf(char * str,size_t size,const char * format,...)63 static int e_snprintf(char *str, size_t size, const char *format, ...)
64 {
65 int ret;
66 va_list ap;
67 va_start(ap, format);
68 ret = vsnprintf(str, size, format, ap);
69 va_end(ap);
70 if (ret >= (int)size)
71 ret = -E2BIG;
72 return ret;
73 }
74
75 static char *synthesize_perf_probe_point(struct perf_probe_point *pp);
76 static struct machine machine;
77
78 /* Initialize symbol maps and path of vmlinux/modules */
init_vmlinux(void)79 static int init_vmlinux(void)
80 {
81 int ret;
82
83 symbol_conf.sort_by_name = true;
84 if (symbol_conf.vmlinux_name == NULL)
85 symbol_conf.try_vmlinux_path = true;
86 else
87 pr_debug("Use vmlinux: %s\n", symbol_conf.vmlinux_name);
88 ret = symbol__init();
89 if (ret < 0) {
90 pr_debug("Failed to init symbol map.\n");
91 goto out;
92 }
93
94 ret = machine__init(&machine, "", HOST_KERNEL_ID);
95 if (ret < 0)
96 goto out;
97
98 if (machine__create_kernel_maps(&machine) < 0) {
99 pr_debug("machine__create_kernel_maps() failed.\n");
100 goto out;
101 }
102 out:
103 if (ret < 0)
104 pr_warning("Failed to init vmlinux path.\n");
105 return ret;
106 }
107
__find_kernel_function_by_name(const char * name,struct map ** mapp)108 static struct symbol *__find_kernel_function_by_name(const char *name,
109 struct map **mapp)
110 {
111 return machine__find_kernel_function_by_name(&machine, name, mapp,
112 NULL);
113 }
114
kernel_get_module_map(const char * module)115 static struct map *kernel_get_module_map(const char *module)
116 {
117 struct rb_node *nd;
118 struct map_groups *grp = &machine.kmaps;
119
120 if (!module)
121 module = "kernel";
122
123 for (nd = rb_first(&grp->maps[MAP__FUNCTION]); nd; nd = rb_next(nd)) {
124 struct map *pos = rb_entry(nd, struct map, rb_node);
125 if (strncmp(pos->dso->short_name + 1, module,
126 pos->dso->short_name_len - 2) == 0) {
127 return pos;
128 }
129 }
130 return NULL;
131 }
132
kernel_get_module_dso(const char * module)133 static struct dso *kernel_get_module_dso(const char *module)
134 {
135 struct dso *dso;
136 struct map *map;
137 const char *vmlinux_name;
138
139 if (module) {
140 list_for_each_entry(dso, &machine.kernel_dsos, node) {
141 if (strncmp(dso->short_name + 1, module,
142 dso->short_name_len - 2) == 0)
143 goto found;
144 }
145 pr_debug("Failed to find module %s.\n", module);
146 return NULL;
147 }
148
149 map = machine.vmlinux_maps[MAP__FUNCTION];
150 dso = map->dso;
151
152 vmlinux_name = symbol_conf.vmlinux_name;
153 if (vmlinux_name) {
154 if (dso__load_vmlinux(dso, map, vmlinux_name, NULL) <= 0)
155 return NULL;
156 } else {
157 if (dso__load_vmlinux_path(dso, map, NULL) <= 0) {
158 pr_debug("Failed to load kernel map.\n");
159 return NULL;
160 }
161 }
162 found:
163 return dso;
164 }
165
kernel_get_module_path(const char * module)166 const char *kernel_get_module_path(const char *module)
167 {
168 struct dso *dso = kernel_get_module_dso(module);
169 return (dso) ? dso->long_name : NULL;
170 }
171
172 #ifdef DWARF_SUPPORT
open_vmlinux(const char * module)173 static int open_vmlinux(const char *module)
174 {
175 const char *path = kernel_get_module_path(module);
176 if (!path) {
177 pr_err("Failed to find path of %s module.\n",
178 module ?: "kernel");
179 return -ENOENT;
180 }
181 pr_debug("Try to open %s\n", path);
182 return open(path, O_RDONLY);
183 }
184
185 /*
186 * Convert trace point to probe point with debuginfo
187 * Currently only handles kprobes.
188 */
kprobe_convert_to_perf_probe(struct probe_trace_point * tp,struct perf_probe_point * pp)189 static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp,
190 struct perf_probe_point *pp)
191 {
192 struct symbol *sym;
193 struct map *map;
194 u64 addr;
195 int ret = -ENOENT;
196
197 sym = __find_kernel_function_by_name(tp->symbol, &map);
198 if (sym) {
199 addr = map->unmap_ip(map, sym->start + tp->offset);
200 pr_debug("try to find %s+%ld@%" PRIx64 "\n", tp->symbol,
201 tp->offset, addr);
202 ret = find_perf_probe_point((unsigned long)addr, pp);
203 }
204 if (ret <= 0) {
205 pr_debug("Failed to find corresponding probes from "
206 "debuginfo. Use kprobe event information.\n");
207 pp->function = strdup(tp->symbol);
208 if (pp->function == NULL)
209 return -ENOMEM;
210 pp->offset = tp->offset;
211 }
212 pp->retprobe = tp->retprobe;
213
214 return 0;
215 }
216
217 /* Try to find perf_probe_event with debuginfo */
try_to_find_probe_trace_events(struct perf_probe_event * pev,struct probe_trace_event ** tevs,int max_tevs,const char * module)218 static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
219 struct probe_trace_event **tevs,
220 int max_tevs, const char *module)
221 {
222 bool need_dwarf = perf_probe_event_need_dwarf(pev);
223 int fd, ntevs;
224
225 fd = open_vmlinux(module);
226 if (fd < 0) {
227 if (need_dwarf) {
228 pr_warning("Failed to open debuginfo file.\n");
229 return fd;
230 }
231 pr_debug("Could not open vmlinux. Try to use symbols.\n");
232 return 0;
233 }
234
235 /* Searching trace events corresponding to probe event */
236 ntevs = find_probe_trace_events(fd, pev, tevs, max_tevs);
237
238 if (ntevs > 0) { /* Succeeded to find trace events */
239 pr_debug("find %d probe_trace_events.\n", ntevs);
240 return ntevs;
241 }
242
243 if (ntevs == 0) { /* No error but failed to find probe point. */
244 pr_warning("Probe point '%s' not found.\n",
245 synthesize_perf_probe_point(&pev->point));
246 return -ENOENT;
247 }
248 /* Error path : ntevs < 0 */
249 pr_debug("An error occurred in debuginfo analysis (%d).\n", ntevs);
250 if (ntevs == -EBADF) {
251 pr_warning("Warning: No dwarf info found in the vmlinux - "
252 "please rebuild kernel with CONFIG_DEBUG_INFO=y.\n");
253 if (!need_dwarf) {
254 pr_debug("Trying to use symbols.\n");
255 return 0;
256 }
257 }
258 return ntevs;
259 }
260
261 /*
262 * Find a src file from a DWARF tag path. Prepend optional source path prefix
263 * and chop off leading directories that do not exist. Result is passed back as
264 * a newly allocated path on success.
265 * Return 0 if file was found and readable, -errno otherwise.
266 */
get_real_path(const char * raw_path,const char * comp_dir,char ** new_path)267 static int get_real_path(const char *raw_path, const char *comp_dir,
268 char **new_path)
269 {
270 const char *prefix = symbol_conf.source_prefix;
271
272 if (!prefix) {
273 if (raw_path[0] != '/' && comp_dir)
274 /* If not an absolute path, try to use comp_dir */
275 prefix = comp_dir;
276 else {
277 if (access(raw_path, R_OK) == 0) {
278 *new_path = strdup(raw_path);
279 return 0;
280 } else
281 return -errno;
282 }
283 }
284
285 *new_path = malloc((strlen(prefix) + strlen(raw_path) + 2));
286 if (!*new_path)
287 return -ENOMEM;
288
289 for (;;) {
290 sprintf(*new_path, "%s/%s", prefix, raw_path);
291
292 if (access(*new_path, R_OK) == 0)
293 return 0;
294
295 if (!symbol_conf.source_prefix)
296 /* In case of searching comp_dir, don't retry */
297 return -errno;
298
299 switch (errno) {
300 case ENAMETOOLONG:
301 case ENOENT:
302 case EROFS:
303 case EFAULT:
304 raw_path = strchr(++raw_path, '/');
305 if (!raw_path) {
306 free(*new_path);
307 *new_path = NULL;
308 return -ENOENT;
309 }
310 continue;
311
312 default:
313 free(*new_path);
314 *new_path = NULL;
315 return -errno;
316 }
317 }
318 }
319
320 #define LINEBUF_SIZE 256
321 #define NR_ADDITIONAL_LINES 2
322
__show_one_line(FILE * fp,int l,bool skip,bool show_num)323 static int __show_one_line(FILE *fp, int l, bool skip, bool show_num)
324 {
325 char buf[LINEBUF_SIZE];
326 const char *color = show_num ? "" : PERF_COLOR_BLUE;
327 const char *prefix = NULL;
328
329 do {
330 if (fgets(buf, LINEBUF_SIZE, fp) == NULL)
331 goto error;
332 if (skip)
333 continue;
334 if (!prefix) {
335 prefix = show_num ? "%7d " : " ";
336 color_fprintf(stdout, color, prefix, l);
337 }
338 color_fprintf(stdout, color, "%s", buf);
339
340 } while (strchr(buf, '\n') == NULL);
341
342 return 1;
343 error:
344 if (ferror(fp)) {
345 pr_warning("File read error: %s\n", strerror(errno));
346 return -1;
347 }
348 return 0;
349 }
350
_show_one_line(FILE * fp,int l,bool skip,bool show_num)351 static int _show_one_line(FILE *fp, int l, bool skip, bool show_num)
352 {
353 int rv = __show_one_line(fp, l, skip, show_num);
354 if (rv == 0) {
355 pr_warning("Source file is shorter than expected.\n");
356 rv = -1;
357 }
358 return rv;
359 }
360
361 #define show_one_line_with_num(f,l) _show_one_line(f,l,false,true)
362 #define show_one_line(f,l) _show_one_line(f,l,false,false)
363 #define skip_one_line(f,l) _show_one_line(f,l,true,false)
364 #define show_one_line_or_eof(f,l) __show_one_line(f,l,false,false)
365
366 /*
367 * Show line-range always requires debuginfo to find source file and
368 * line number.
369 */
show_line_range(struct line_range * lr,const char * module)370 int show_line_range(struct line_range *lr, const char *module)
371 {
372 int l = 1;
373 struct line_node *ln;
374 FILE *fp;
375 int fd, ret;
376 char *tmp;
377
378 /* Search a line range */
379 ret = init_vmlinux();
380 if (ret < 0)
381 return ret;
382
383 fd = open_vmlinux(module);
384 if (fd < 0) {
385 pr_warning("Failed to open debuginfo file.\n");
386 return fd;
387 }
388
389 ret = find_line_range(fd, lr);
390 if (ret == 0) {
391 pr_warning("Specified source line is not found.\n");
392 return -ENOENT;
393 } else if (ret < 0) {
394 pr_warning("Debuginfo analysis failed. (%d)\n", ret);
395 return ret;
396 }
397
398 /* Convert source file path */
399 tmp = lr->path;
400 ret = get_real_path(tmp, lr->comp_dir, &lr->path);
401 free(tmp); /* Free old path */
402 if (ret < 0) {
403 pr_warning("Failed to find source file. (%d)\n", ret);
404 return ret;
405 }
406
407 setup_pager();
408
409 if (lr->function)
410 fprintf(stdout, "<%s@%s:%d>\n", lr->function, lr->path,
411 lr->start - lr->offset);
412 else
413 fprintf(stdout, "<%s:%d>\n", lr->path, lr->start);
414
415 fp = fopen(lr->path, "r");
416 if (fp == NULL) {
417 pr_warning("Failed to open %s: %s\n", lr->path,
418 strerror(errno));
419 return -errno;
420 }
421 /* Skip to starting line number */
422 while (l < lr->start) {
423 ret = skip_one_line(fp, l++);
424 if (ret < 0)
425 goto end;
426 }
427
428 list_for_each_entry(ln, &lr->line_list, list) {
429 for (; ln->line > l; l++) {
430 ret = show_one_line(fp, l - lr->offset);
431 if (ret < 0)
432 goto end;
433 }
434 ret = show_one_line_with_num(fp, l++ - lr->offset);
435 if (ret < 0)
436 goto end;
437 }
438
439 if (lr->end == INT_MAX)
440 lr->end = l + NR_ADDITIONAL_LINES;
441 while (l <= lr->end) {
442 ret = show_one_line_or_eof(fp, l++ - lr->offset);
443 if (ret <= 0)
444 break;
445 }
446 end:
447 fclose(fp);
448 return ret;
449 }
450
show_available_vars_at(int fd,struct perf_probe_event * pev,int max_vls,struct strfilter * _filter,bool externs)451 static int show_available_vars_at(int fd, struct perf_probe_event *pev,
452 int max_vls, struct strfilter *_filter,
453 bool externs)
454 {
455 char *buf;
456 int ret, i, nvars;
457 struct str_node *node;
458 struct variable_list *vls = NULL, *vl;
459 const char *var;
460
461 buf = synthesize_perf_probe_point(&pev->point);
462 if (!buf)
463 return -EINVAL;
464 pr_debug("Searching variables at %s\n", buf);
465
466 ret = find_available_vars_at(fd, pev, &vls, max_vls, externs);
467 if (ret <= 0) {
468 pr_err("Failed to find variables at %s (%d)\n", buf, ret);
469 goto end;
470 }
471 /* Some variables are found */
472 fprintf(stdout, "Available variables at %s\n", buf);
473 for (i = 0; i < ret; i++) {
474 vl = &vls[i];
475 /*
476 * A probe point might be converted to
477 * several trace points.
478 */
479 fprintf(stdout, "\t@<%s+%lu>\n", vl->point.symbol,
480 vl->point.offset);
481 free(vl->point.symbol);
482 nvars = 0;
483 if (vl->vars) {
484 strlist__for_each(node, vl->vars) {
485 var = strchr(node->s, '\t') + 1;
486 if (strfilter__compare(_filter, var)) {
487 fprintf(stdout, "\t\t%s\n", node->s);
488 nvars++;
489 }
490 }
491 strlist__delete(vl->vars);
492 }
493 if (nvars == 0)
494 fprintf(stdout, "\t\t(No matched variables)\n");
495 }
496 free(vls);
497 end:
498 free(buf);
499 return ret;
500 }
501
502 /* Show available variables on given probe point */
show_available_vars(struct perf_probe_event * pevs,int npevs,int max_vls,const char * module,struct strfilter * _filter,bool externs)503 int show_available_vars(struct perf_probe_event *pevs, int npevs,
504 int max_vls, const char *module,
505 struct strfilter *_filter, bool externs)
506 {
507 int i, fd, ret = 0;
508
509 ret = init_vmlinux();
510 if (ret < 0)
511 return ret;
512
513 setup_pager();
514
515 for (i = 0; i < npevs && ret >= 0; i++) {
516 fd = open_vmlinux(module);
517 if (fd < 0) {
518 pr_warning("Failed to open debug information file.\n");
519 ret = fd;
520 break;
521 }
522 ret = show_available_vars_at(fd, &pevs[i], max_vls, _filter,
523 externs);
524 }
525 return ret;
526 }
527
528 #else /* !DWARF_SUPPORT */
529
kprobe_convert_to_perf_probe(struct probe_trace_point * tp,struct perf_probe_point * pp)530 static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp,
531 struct perf_probe_point *pp)
532 {
533 struct symbol *sym;
534
535 sym = __find_kernel_function_by_name(tp->symbol, NULL);
536 if (!sym) {
537 pr_err("Failed to find symbol %s in kernel.\n", tp->symbol);
538 return -ENOENT;
539 }
540 pp->function = strdup(tp->symbol);
541 if (pp->function == NULL)
542 return -ENOMEM;
543 pp->offset = tp->offset;
544 pp->retprobe = tp->retprobe;
545
546 return 0;
547 }
548
try_to_find_probe_trace_events(struct perf_probe_event * pev,struct probe_trace_event ** tevs __unused,int max_tevs __unused,const char * mod __unused)549 static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
550 struct probe_trace_event **tevs __unused,
551 int max_tevs __unused, const char *mod __unused)
552 {
553 if (perf_probe_event_need_dwarf(pev)) {
554 pr_warning("Debuginfo-analysis is not supported.\n");
555 return -ENOSYS;
556 }
557 return 0;
558 }
559
show_line_range(struct line_range * lr __unused,const char * module __unused)560 int show_line_range(struct line_range *lr __unused, const char *module __unused)
561 {
562 pr_warning("Debuginfo-analysis is not supported.\n");
563 return -ENOSYS;
564 }
565
show_available_vars(struct perf_probe_event * pevs __unused,int npevs __unused,int max_vls __unused,const char * module __unused,struct strfilter * filter __unused,bool externs __unused)566 int show_available_vars(struct perf_probe_event *pevs __unused,
567 int npevs __unused, int max_vls __unused,
568 const char *module __unused,
569 struct strfilter *filter __unused,
570 bool externs __unused)
571 {
572 pr_warning("Debuginfo-analysis is not supported.\n");
573 return -ENOSYS;
574 }
575 #endif
576
parse_line_num(char ** ptr,int * val,const char * what)577 static int parse_line_num(char **ptr, int *val, const char *what)
578 {
579 const char *start = *ptr;
580
581 errno = 0;
582 *val = strtol(*ptr, ptr, 0);
583 if (errno || *ptr == start) {
584 semantic_error("'%s' is not a valid number.\n", what);
585 return -EINVAL;
586 }
587 return 0;
588 }
589
590 /*
591 * Stuff 'lr' according to the line range described by 'arg'.
592 * The line range syntax is described by:
593 *
594 * SRC[:SLN[+NUM|-ELN]]
595 * FNC[@SRC][:SLN[+NUM|-ELN]]
596 */
parse_line_range_desc(const char * arg,struct line_range * lr)597 int parse_line_range_desc(const char *arg, struct line_range *lr)
598 {
599 char *range, *file, *name = strdup(arg);
600 int err;
601
602 if (!name)
603 return -ENOMEM;
604
605 lr->start = 0;
606 lr->end = INT_MAX;
607
608 range = strchr(name, ':');
609 if (range) {
610 *range++ = '\0';
611
612 err = parse_line_num(&range, &lr->start, "start line");
613 if (err)
614 goto err;
615
616 if (*range == '+' || *range == '-') {
617 const char c = *range++;
618
619 err = parse_line_num(&range, &lr->end, "end line");
620 if (err)
621 goto err;
622
623 if (c == '+') {
624 lr->end += lr->start;
625 /*
626 * Adjust the number of lines here.
627 * If the number of lines == 1, the
628 * the end of line should be equal to
629 * the start of line.
630 */
631 lr->end--;
632 }
633 }
634
635 pr_debug("Line range is %d to %d\n", lr->start, lr->end);
636
637 err = -EINVAL;
638 if (lr->start > lr->end) {
639 semantic_error("Start line must be smaller"
640 " than end line.\n");
641 goto err;
642 }
643 if (*range != '\0') {
644 semantic_error("Tailing with invalid str '%s'.\n", range);
645 goto err;
646 }
647 }
648
649 file = strchr(name, '@');
650 if (file) {
651 *file = '\0';
652 lr->file = strdup(++file);
653 if (lr->file == NULL) {
654 err = -ENOMEM;
655 goto err;
656 }
657 lr->function = name;
658 } else if (strchr(name, '.'))
659 lr->file = name;
660 else
661 lr->function = name;
662
663 return 0;
664 err:
665 free(name);
666 return err;
667 }
668
669 /* Check the name is good for event/group */
check_event_name(const char * name)670 static bool check_event_name(const char *name)
671 {
672 if (!isalpha(*name) && *name != '_')
673 return false;
674 while (*++name != '\0') {
675 if (!isalpha(*name) && !isdigit(*name) && *name != '_')
676 return false;
677 }
678 return true;
679 }
680
681 /* Parse probepoint definition. */
parse_perf_probe_point(char * arg,struct perf_probe_event * pev)682 static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev)
683 {
684 struct perf_probe_point *pp = &pev->point;
685 char *ptr, *tmp;
686 char c, nc = 0;
687 /*
688 * <Syntax>
689 * perf probe [EVENT=]SRC[:LN|;PTN]
690 * perf probe [EVENT=]FUNC[@SRC][+OFFS|%return|:LN|;PAT]
691 *
692 * TODO:Group name support
693 */
694
695 ptr = strpbrk(arg, ";=@+%");
696 if (ptr && *ptr == '=') { /* Event name */
697 *ptr = '\0';
698 tmp = ptr + 1;
699 if (strchr(arg, ':')) {
700 semantic_error("Group name is not supported yet.\n");
701 return -ENOTSUP;
702 }
703 if (!check_event_name(arg)) {
704 semantic_error("%s is bad for event name -it must "
705 "follow C symbol-naming rule.\n", arg);
706 return -EINVAL;
707 }
708 pev->event = strdup(arg);
709 if (pev->event == NULL)
710 return -ENOMEM;
711 pev->group = NULL;
712 arg = tmp;
713 }
714
715 ptr = strpbrk(arg, ";:+@%");
716 if (ptr) {
717 nc = *ptr;
718 *ptr++ = '\0';
719 }
720
721 tmp = strdup(arg);
722 if (tmp == NULL)
723 return -ENOMEM;
724
725 /* Check arg is function or file and copy it */
726 if (strchr(tmp, '.')) /* File */
727 pp->file = tmp;
728 else /* Function */
729 pp->function = tmp;
730
731 /* Parse other options */
732 while (ptr) {
733 arg = ptr;
734 c = nc;
735 if (c == ';') { /* Lazy pattern must be the last part */
736 pp->lazy_line = strdup(arg);
737 if (pp->lazy_line == NULL)
738 return -ENOMEM;
739 break;
740 }
741 ptr = strpbrk(arg, ";:+@%");
742 if (ptr) {
743 nc = *ptr;
744 *ptr++ = '\0';
745 }
746 switch (c) {
747 case ':': /* Line number */
748 pp->line = strtoul(arg, &tmp, 0);
749 if (*tmp != '\0') {
750 semantic_error("There is non-digit char"
751 " in line number.\n");
752 return -EINVAL;
753 }
754 break;
755 case '+': /* Byte offset from a symbol */
756 pp->offset = strtoul(arg, &tmp, 0);
757 if (*tmp != '\0') {
758 semantic_error("There is non-digit character"
759 " in offset.\n");
760 return -EINVAL;
761 }
762 break;
763 case '@': /* File name */
764 if (pp->file) {
765 semantic_error("SRC@SRC is not allowed.\n");
766 return -EINVAL;
767 }
768 pp->file = strdup(arg);
769 if (pp->file == NULL)
770 return -ENOMEM;
771 break;
772 case '%': /* Probe places */
773 if (strcmp(arg, "return") == 0) {
774 pp->retprobe = 1;
775 } else { /* Others not supported yet */
776 semantic_error("%%%s is not supported.\n", arg);
777 return -ENOTSUP;
778 }
779 break;
780 default: /* Buggy case */
781 pr_err("This program has a bug at %s:%d.\n",
782 __FILE__, __LINE__);
783 return -ENOTSUP;
784 break;
785 }
786 }
787
788 /* Exclusion check */
789 if (pp->lazy_line && pp->line) {
790 semantic_error("Lazy pattern can't be used with"
791 " line number.\n");
792 return -EINVAL;
793 }
794
795 if (pp->lazy_line && pp->offset) {
796 semantic_error("Lazy pattern can't be used with offset.\n");
797 return -EINVAL;
798 }
799
800 if (pp->line && pp->offset) {
801 semantic_error("Offset can't be used with line number.\n");
802 return -EINVAL;
803 }
804
805 if (!pp->line && !pp->lazy_line && pp->file && !pp->function) {
806 semantic_error("File always requires line number or "
807 "lazy pattern.\n");
808 return -EINVAL;
809 }
810
811 if (pp->offset && !pp->function) {
812 semantic_error("Offset requires an entry function.\n");
813 return -EINVAL;
814 }
815
816 if (pp->retprobe && !pp->function) {
817 semantic_error("Return probe requires an entry function.\n");
818 return -EINVAL;
819 }
820
821 if ((pp->offset || pp->line || pp->lazy_line) && pp->retprobe) {
822 semantic_error("Offset/Line/Lazy pattern can't be used with "
823 "return probe.\n");
824 return -EINVAL;
825 }
826
827 pr_debug("symbol:%s file:%s line:%d offset:%lu return:%d lazy:%s\n",
828 pp->function, pp->file, pp->line, pp->offset, pp->retprobe,
829 pp->lazy_line);
830 return 0;
831 }
832
833 /* Parse perf-probe event argument */
parse_perf_probe_arg(char * str,struct perf_probe_arg * arg)834 static int parse_perf_probe_arg(char *str, struct perf_probe_arg *arg)
835 {
836 char *tmp, *goodname;
837 struct perf_probe_arg_field **fieldp;
838
839 pr_debug("parsing arg: %s into ", str);
840
841 tmp = strchr(str, '=');
842 if (tmp) {
843 arg->name = strndup(str, tmp - str);
844 if (arg->name == NULL)
845 return -ENOMEM;
846 pr_debug("name:%s ", arg->name);
847 str = tmp + 1;
848 }
849
850 tmp = strchr(str, ':');
851 if (tmp) { /* Type setting */
852 *tmp = '\0';
853 arg->type = strdup(tmp + 1);
854 if (arg->type == NULL)
855 return -ENOMEM;
856 pr_debug("type:%s ", arg->type);
857 }
858
859 tmp = strpbrk(str, "-.[");
860 if (!is_c_varname(str) || !tmp) {
861 /* A variable, register, symbol or special value */
862 arg->var = strdup(str);
863 if (arg->var == NULL)
864 return -ENOMEM;
865 pr_debug("%s\n", arg->var);
866 return 0;
867 }
868
869 /* Structure fields or array element */
870 arg->var = strndup(str, tmp - str);
871 if (arg->var == NULL)
872 return -ENOMEM;
873 goodname = arg->var;
874 pr_debug("%s, ", arg->var);
875 fieldp = &arg->field;
876
877 do {
878 *fieldp = zalloc(sizeof(struct perf_probe_arg_field));
879 if (*fieldp == NULL)
880 return -ENOMEM;
881 if (*tmp == '[') { /* Array */
882 str = tmp;
883 (*fieldp)->index = strtol(str + 1, &tmp, 0);
884 (*fieldp)->ref = true;
885 if (*tmp != ']' || tmp == str + 1) {
886 semantic_error("Array index must be a"
887 " number.\n");
888 return -EINVAL;
889 }
890 tmp++;
891 if (*tmp == '\0')
892 tmp = NULL;
893 } else { /* Structure */
894 if (*tmp == '.') {
895 str = tmp + 1;
896 (*fieldp)->ref = false;
897 } else if (tmp[1] == '>') {
898 str = tmp + 2;
899 (*fieldp)->ref = true;
900 } else {
901 semantic_error("Argument parse error: %s\n",
902 str);
903 return -EINVAL;
904 }
905 tmp = strpbrk(str, "-.[");
906 }
907 if (tmp) {
908 (*fieldp)->name = strndup(str, tmp - str);
909 if ((*fieldp)->name == NULL)
910 return -ENOMEM;
911 if (*str != '[')
912 goodname = (*fieldp)->name;
913 pr_debug("%s(%d), ", (*fieldp)->name, (*fieldp)->ref);
914 fieldp = &(*fieldp)->next;
915 }
916 } while (tmp);
917 (*fieldp)->name = strdup(str);
918 if ((*fieldp)->name == NULL)
919 return -ENOMEM;
920 if (*str != '[')
921 goodname = (*fieldp)->name;
922 pr_debug("%s(%d)\n", (*fieldp)->name, (*fieldp)->ref);
923
924 /* If no name is specified, set the last field name (not array index)*/
925 if (!arg->name) {
926 arg->name = strdup(goodname);
927 if (arg->name == NULL)
928 return -ENOMEM;
929 }
930 return 0;
931 }
932
933 /* Parse perf-probe event command */
parse_perf_probe_command(const char * cmd,struct perf_probe_event * pev)934 int parse_perf_probe_command(const char *cmd, struct perf_probe_event *pev)
935 {
936 char **argv;
937 int argc, i, ret = 0;
938
939 argv = argv_split(cmd, &argc);
940 if (!argv) {
941 pr_debug("Failed to split arguments.\n");
942 return -ENOMEM;
943 }
944 if (argc - 1 > MAX_PROBE_ARGS) {
945 semantic_error("Too many probe arguments (%d).\n", argc - 1);
946 ret = -ERANGE;
947 goto out;
948 }
949 /* Parse probe point */
950 ret = parse_perf_probe_point(argv[0], pev);
951 if (ret < 0)
952 goto out;
953
954 /* Copy arguments and ensure return probe has no C argument */
955 pev->nargs = argc - 1;
956 pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs);
957 if (pev->args == NULL) {
958 ret = -ENOMEM;
959 goto out;
960 }
961 for (i = 0; i < pev->nargs && ret >= 0; i++) {
962 ret = parse_perf_probe_arg(argv[i + 1], &pev->args[i]);
963 if (ret >= 0 &&
964 is_c_varname(pev->args[i].var) && pev->point.retprobe) {
965 semantic_error("You can't specify local variable for"
966 " kretprobe.\n");
967 ret = -EINVAL;
968 }
969 }
970 out:
971 argv_free(argv);
972
973 return ret;
974 }
975
976 /* Return true if this perf_probe_event requires debuginfo */
perf_probe_event_need_dwarf(struct perf_probe_event * pev)977 bool perf_probe_event_need_dwarf(struct perf_probe_event *pev)
978 {
979 int i;
980
981 if (pev->point.file || pev->point.line || pev->point.lazy_line)
982 return true;
983
984 for (i = 0; i < pev->nargs; i++)
985 if (is_c_varname(pev->args[i].var))
986 return true;
987
988 return false;
989 }
990
991 /* Parse probe_events event into struct probe_point */
parse_probe_trace_command(const char * cmd,struct probe_trace_event * tev)992 static int parse_probe_trace_command(const char *cmd,
993 struct probe_trace_event *tev)
994 {
995 struct probe_trace_point *tp = &tev->point;
996 char pr;
997 char *p;
998 int ret, i, argc;
999 char **argv;
1000
1001 pr_debug("Parsing probe_events: %s\n", cmd);
1002 argv = argv_split(cmd, &argc);
1003 if (!argv) {
1004 pr_debug("Failed to split arguments.\n");
1005 return -ENOMEM;
1006 }
1007 if (argc < 2) {
1008 semantic_error("Too few probe arguments.\n");
1009 ret = -ERANGE;
1010 goto out;
1011 }
1012
1013 /* Scan event and group name. */
1014 ret = sscanf(argv[0], "%c:%a[^/ \t]/%a[^ \t]",
1015 &pr, (float *)(void *)&tev->group,
1016 (float *)(void *)&tev->event);
1017 if (ret != 3) {
1018 semantic_error("Failed to parse event name: %s\n", argv[0]);
1019 ret = -EINVAL;
1020 goto out;
1021 }
1022 pr_debug("Group:%s Event:%s probe:%c\n", tev->group, tev->event, pr);
1023
1024 tp->retprobe = (pr == 'r');
1025
1026 /* Scan function name and offset */
1027 ret = sscanf(argv[1], "%a[^+]+%lu", (float *)(void *)&tp->symbol,
1028 &tp->offset);
1029 if (ret == 1)
1030 tp->offset = 0;
1031
1032 tev->nargs = argc - 2;
1033 tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
1034 if (tev->args == NULL) {
1035 ret = -ENOMEM;
1036 goto out;
1037 }
1038 for (i = 0; i < tev->nargs; i++) {
1039 p = strchr(argv[i + 2], '=');
1040 if (p) /* We don't need which register is assigned. */
1041 *p++ = '\0';
1042 else
1043 p = argv[i + 2];
1044 tev->args[i].name = strdup(argv[i + 2]);
1045 /* TODO: parse regs and offset */
1046 tev->args[i].value = strdup(p);
1047 if (tev->args[i].name == NULL || tev->args[i].value == NULL) {
1048 ret = -ENOMEM;
1049 goto out;
1050 }
1051 }
1052 ret = 0;
1053 out:
1054 argv_free(argv);
1055 return ret;
1056 }
1057
1058 /* Compose only probe arg */
synthesize_perf_probe_arg(struct perf_probe_arg * pa,char * buf,size_t len)1059 int synthesize_perf_probe_arg(struct perf_probe_arg *pa, char *buf, size_t len)
1060 {
1061 struct perf_probe_arg_field *field = pa->field;
1062 int ret;
1063 char *tmp = buf;
1064
1065 if (pa->name && pa->var)
1066 ret = e_snprintf(tmp, len, "%s=%s", pa->name, pa->var);
1067 else
1068 ret = e_snprintf(tmp, len, "%s", pa->name ? pa->name : pa->var);
1069 if (ret <= 0)
1070 goto error;
1071 tmp += ret;
1072 len -= ret;
1073
1074 while (field) {
1075 if (field->name[0] == '[')
1076 ret = e_snprintf(tmp, len, "%s", field->name);
1077 else
1078 ret = e_snprintf(tmp, len, "%s%s",
1079 field->ref ? "->" : ".", field->name);
1080 if (ret <= 0)
1081 goto error;
1082 tmp += ret;
1083 len -= ret;
1084 field = field->next;
1085 }
1086
1087 if (pa->type) {
1088 ret = e_snprintf(tmp, len, ":%s", pa->type);
1089 if (ret <= 0)
1090 goto error;
1091 tmp += ret;
1092 len -= ret;
1093 }
1094
1095 return tmp - buf;
1096 error:
1097 pr_debug("Failed to synthesize perf probe argument: %s\n",
1098 strerror(-ret));
1099 return ret;
1100 }
1101
1102 /* Compose only probe point (not argument) */
synthesize_perf_probe_point(struct perf_probe_point * pp)1103 static char *synthesize_perf_probe_point(struct perf_probe_point *pp)
1104 {
1105 char *buf, *tmp;
1106 char offs[32] = "", line[32] = "", file[32] = "";
1107 int ret, len;
1108
1109 buf = zalloc(MAX_CMDLEN);
1110 if (buf == NULL) {
1111 ret = -ENOMEM;
1112 goto error;
1113 }
1114 if (pp->offset) {
1115 ret = e_snprintf(offs, 32, "+%lu", pp->offset);
1116 if (ret <= 0)
1117 goto error;
1118 }
1119 if (pp->line) {
1120 ret = e_snprintf(line, 32, ":%d", pp->line);
1121 if (ret <= 0)
1122 goto error;
1123 }
1124 if (pp->file) {
1125 tmp = pp->file;
1126 len = strlen(tmp);
1127 if (len > 30) {
1128 tmp = strchr(pp->file + len - 30, '/');
1129 tmp = tmp ? tmp + 1 : pp->file + len - 30;
1130 }
1131 ret = e_snprintf(file, 32, "@%s", tmp);
1132 if (ret <= 0)
1133 goto error;
1134 }
1135
1136 if (pp->function)
1137 ret = e_snprintf(buf, MAX_CMDLEN, "%s%s%s%s%s", pp->function,
1138 offs, pp->retprobe ? "%return" : "", line,
1139 file);
1140 else
1141 ret = e_snprintf(buf, MAX_CMDLEN, "%s%s", file, line);
1142 if (ret <= 0)
1143 goto error;
1144
1145 return buf;
1146 error:
1147 pr_debug("Failed to synthesize perf probe point: %s\n",
1148 strerror(-ret));
1149 if (buf)
1150 free(buf);
1151 return NULL;
1152 }
1153
1154 #if 0
1155 char *synthesize_perf_probe_command(struct perf_probe_event *pev)
1156 {
1157 char *buf;
1158 int i, len, ret;
1159
1160 buf = synthesize_perf_probe_point(&pev->point);
1161 if (!buf)
1162 return NULL;
1163
1164 len = strlen(buf);
1165 for (i = 0; i < pev->nargs; i++) {
1166 ret = e_snprintf(&buf[len], MAX_CMDLEN - len, " %s",
1167 pev->args[i].name);
1168 if (ret <= 0) {
1169 free(buf);
1170 return NULL;
1171 }
1172 len += ret;
1173 }
1174
1175 return buf;
1176 }
1177 #endif
1178
__synthesize_probe_trace_arg_ref(struct probe_trace_arg_ref * ref,char ** buf,size_t * buflen,int depth)1179 static int __synthesize_probe_trace_arg_ref(struct probe_trace_arg_ref *ref,
1180 char **buf, size_t *buflen,
1181 int depth)
1182 {
1183 int ret;
1184 if (ref->next) {
1185 depth = __synthesize_probe_trace_arg_ref(ref->next, buf,
1186 buflen, depth + 1);
1187 if (depth < 0)
1188 goto out;
1189 }
1190
1191 ret = e_snprintf(*buf, *buflen, "%+ld(", ref->offset);
1192 if (ret < 0)
1193 depth = ret;
1194 else {
1195 *buf += ret;
1196 *buflen -= ret;
1197 }
1198 out:
1199 return depth;
1200
1201 }
1202
synthesize_probe_trace_arg(struct probe_trace_arg * arg,char * buf,size_t buflen)1203 static int synthesize_probe_trace_arg(struct probe_trace_arg *arg,
1204 char *buf, size_t buflen)
1205 {
1206 struct probe_trace_arg_ref *ref = arg->ref;
1207 int ret, depth = 0;
1208 char *tmp = buf;
1209
1210 /* Argument name or separator */
1211 if (arg->name)
1212 ret = e_snprintf(buf, buflen, " %s=", arg->name);
1213 else
1214 ret = e_snprintf(buf, buflen, " ");
1215 if (ret < 0)
1216 return ret;
1217 buf += ret;
1218 buflen -= ret;
1219
1220 /* Special case: @XXX */
1221 if (arg->value[0] == '@' && arg->ref)
1222 ref = ref->next;
1223
1224 /* Dereferencing arguments */
1225 if (ref) {
1226 depth = __synthesize_probe_trace_arg_ref(ref, &buf,
1227 &buflen, 1);
1228 if (depth < 0)
1229 return depth;
1230 }
1231
1232 /* Print argument value */
1233 if (arg->value[0] == '@' && arg->ref)
1234 ret = e_snprintf(buf, buflen, "%s%+ld", arg->value,
1235 arg->ref->offset);
1236 else
1237 ret = e_snprintf(buf, buflen, "%s", arg->value);
1238 if (ret < 0)
1239 return ret;
1240 buf += ret;
1241 buflen -= ret;
1242
1243 /* Closing */
1244 while (depth--) {
1245 ret = e_snprintf(buf, buflen, ")");
1246 if (ret < 0)
1247 return ret;
1248 buf += ret;
1249 buflen -= ret;
1250 }
1251 /* Print argument type */
1252 if (arg->type) {
1253 ret = e_snprintf(buf, buflen, ":%s", arg->type);
1254 if (ret <= 0)
1255 return ret;
1256 buf += ret;
1257 }
1258
1259 return buf - tmp;
1260 }
1261
synthesize_probe_trace_command(struct probe_trace_event * tev)1262 char *synthesize_probe_trace_command(struct probe_trace_event *tev)
1263 {
1264 struct probe_trace_point *tp = &tev->point;
1265 char *buf;
1266 int i, len, ret;
1267
1268 buf = zalloc(MAX_CMDLEN);
1269 if (buf == NULL)
1270 return NULL;
1271
1272 len = e_snprintf(buf, MAX_CMDLEN, "%c:%s/%s %s+%lu",
1273 tp->retprobe ? 'r' : 'p',
1274 tev->group, tev->event,
1275 tp->symbol, tp->offset);
1276 if (len <= 0)
1277 goto error;
1278
1279 for (i = 0; i < tev->nargs; i++) {
1280 ret = synthesize_probe_trace_arg(&tev->args[i], buf + len,
1281 MAX_CMDLEN - len);
1282 if (ret <= 0)
1283 goto error;
1284 len += ret;
1285 }
1286
1287 return buf;
1288 error:
1289 free(buf);
1290 return NULL;
1291 }
1292
convert_to_perf_probe_event(struct probe_trace_event * tev,struct perf_probe_event * pev)1293 static int convert_to_perf_probe_event(struct probe_trace_event *tev,
1294 struct perf_probe_event *pev)
1295 {
1296 char buf[64] = "";
1297 int i, ret;
1298
1299 /* Convert event/group name */
1300 pev->event = strdup(tev->event);
1301 pev->group = strdup(tev->group);
1302 if (pev->event == NULL || pev->group == NULL)
1303 return -ENOMEM;
1304
1305 /* Convert trace_point to probe_point */
1306 ret = kprobe_convert_to_perf_probe(&tev->point, &pev->point);
1307 if (ret < 0)
1308 return ret;
1309
1310 /* Convert trace_arg to probe_arg */
1311 pev->nargs = tev->nargs;
1312 pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs);
1313 if (pev->args == NULL)
1314 return -ENOMEM;
1315 for (i = 0; i < tev->nargs && ret >= 0; i++) {
1316 if (tev->args[i].name)
1317 pev->args[i].name = strdup(tev->args[i].name);
1318 else {
1319 ret = synthesize_probe_trace_arg(&tev->args[i],
1320 buf, 64);
1321 pev->args[i].name = strdup(buf);
1322 }
1323 if (pev->args[i].name == NULL && ret >= 0)
1324 ret = -ENOMEM;
1325 }
1326
1327 if (ret < 0)
1328 clear_perf_probe_event(pev);
1329
1330 return ret;
1331 }
1332
clear_perf_probe_event(struct perf_probe_event * pev)1333 void clear_perf_probe_event(struct perf_probe_event *pev)
1334 {
1335 struct perf_probe_point *pp = &pev->point;
1336 struct perf_probe_arg_field *field, *next;
1337 int i;
1338
1339 if (pev->event)
1340 free(pev->event);
1341 if (pev->group)
1342 free(pev->group);
1343 if (pp->file)
1344 free(pp->file);
1345 if (pp->function)
1346 free(pp->function);
1347 if (pp->lazy_line)
1348 free(pp->lazy_line);
1349 for (i = 0; i < pev->nargs; i++) {
1350 if (pev->args[i].name)
1351 free(pev->args[i].name);
1352 if (pev->args[i].var)
1353 free(pev->args[i].var);
1354 if (pev->args[i].type)
1355 free(pev->args[i].type);
1356 field = pev->args[i].field;
1357 while (field) {
1358 next = field->next;
1359 if (field->name)
1360 free(field->name);
1361 free(field);
1362 field = next;
1363 }
1364 }
1365 if (pev->args)
1366 free(pev->args);
1367 memset(pev, 0, sizeof(*pev));
1368 }
1369
clear_probe_trace_event(struct probe_trace_event * tev)1370 static void clear_probe_trace_event(struct probe_trace_event *tev)
1371 {
1372 struct probe_trace_arg_ref *ref, *next;
1373 int i;
1374
1375 if (tev->event)
1376 free(tev->event);
1377 if (tev->group)
1378 free(tev->group);
1379 if (tev->point.symbol)
1380 free(tev->point.symbol);
1381 for (i = 0; i < tev->nargs; i++) {
1382 if (tev->args[i].name)
1383 free(tev->args[i].name);
1384 if (tev->args[i].value)
1385 free(tev->args[i].value);
1386 if (tev->args[i].type)
1387 free(tev->args[i].type);
1388 ref = tev->args[i].ref;
1389 while (ref) {
1390 next = ref->next;
1391 free(ref);
1392 ref = next;
1393 }
1394 }
1395 if (tev->args)
1396 free(tev->args);
1397 memset(tev, 0, sizeof(*tev));
1398 }
1399
open_kprobe_events(bool readwrite)1400 static int open_kprobe_events(bool readwrite)
1401 {
1402 char buf[PATH_MAX];
1403 const char *__debugfs;
1404 int ret;
1405
1406 __debugfs = debugfs_find_mountpoint();
1407 if (__debugfs == NULL) {
1408 pr_warning("Debugfs is not mounted.\n");
1409 return -ENOENT;
1410 }
1411
1412 ret = e_snprintf(buf, PATH_MAX, "%stracing/kprobe_events", __debugfs);
1413 if (ret >= 0) {
1414 pr_debug("Opening %s write=%d\n", buf, readwrite);
1415 if (readwrite && !probe_event_dry_run)
1416 ret = open(buf, O_RDWR, O_APPEND);
1417 else
1418 ret = open(buf, O_RDONLY, 0);
1419 }
1420
1421 if (ret < 0) {
1422 if (errno == ENOENT)
1423 pr_warning("kprobe_events file does not exist - please"
1424 " rebuild kernel with CONFIG_KPROBE_EVENT.\n");
1425 else
1426 pr_warning("Failed to open kprobe_events file: %s\n",
1427 strerror(errno));
1428 }
1429 return ret;
1430 }
1431
1432 /* Get raw string list of current kprobe_events */
get_probe_trace_command_rawlist(int fd)1433 static struct strlist *get_probe_trace_command_rawlist(int fd)
1434 {
1435 int ret, idx;
1436 FILE *fp;
1437 char buf[MAX_CMDLEN];
1438 char *p;
1439 struct strlist *sl;
1440
1441 sl = strlist__new(true, NULL);
1442
1443 fp = fdopen(dup(fd), "r");
1444 while (!feof(fp)) {
1445 p = fgets(buf, MAX_CMDLEN, fp);
1446 if (!p)
1447 break;
1448
1449 idx = strlen(p) - 1;
1450 if (p[idx] == '\n')
1451 p[idx] = '\0';
1452 ret = strlist__add(sl, buf);
1453 if (ret < 0) {
1454 pr_debug("strlist__add failed: %s\n", strerror(-ret));
1455 strlist__delete(sl);
1456 return NULL;
1457 }
1458 }
1459 fclose(fp);
1460
1461 return sl;
1462 }
1463
1464 /* Show an event */
show_perf_probe_event(struct perf_probe_event * pev)1465 static int show_perf_probe_event(struct perf_probe_event *pev)
1466 {
1467 int i, ret;
1468 char buf[128];
1469 char *place;
1470
1471 /* Synthesize only event probe point */
1472 place = synthesize_perf_probe_point(&pev->point);
1473 if (!place)
1474 return -EINVAL;
1475
1476 ret = e_snprintf(buf, 128, "%s:%s", pev->group, pev->event);
1477 if (ret < 0)
1478 return ret;
1479
1480 printf(" %-20s (on %s", buf, place);
1481
1482 if (pev->nargs > 0) {
1483 printf(" with");
1484 for (i = 0; i < pev->nargs; i++) {
1485 ret = synthesize_perf_probe_arg(&pev->args[i],
1486 buf, 128);
1487 if (ret < 0)
1488 break;
1489 printf(" %s", buf);
1490 }
1491 }
1492 printf(")\n");
1493 free(place);
1494 return ret;
1495 }
1496
1497 /* List up current perf-probe events */
show_perf_probe_events(void)1498 int show_perf_probe_events(void)
1499 {
1500 int fd, ret;
1501 struct probe_trace_event tev;
1502 struct perf_probe_event pev;
1503 struct strlist *rawlist;
1504 struct str_node *ent;
1505
1506 setup_pager();
1507 ret = init_vmlinux();
1508 if (ret < 0)
1509 return ret;
1510
1511 memset(&tev, 0, sizeof(tev));
1512 memset(&pev, 0, sizeof(pev));
1513
1514 fd = open_kprobe_events(false);
1515 if (fd < 0)
1516 return fd;
1517
1518 rawlist = get_probe_trace_command_rawlist(fd);
1519 close(fd);
1520 if (!rawlist)
1521 return -ENOENT;
1522
1523 strlist__for_each(ent, rawlist) {
1524 ret = parse_probe_trace_command(ent->s, &tev);
1525 if (ret >= 0) {
1526 ret = convert_to_perf_probe_event(&tev, &pev);
1527 if (ret >= 0)
1528 ret = show_perf_probe_event(&pev);
1529 }
1530 clear_perf_probe_event(&pev);
1531 clear_probe_trace_event(&tev);
1532 if (ret < 0)
1533 break;
1534 }
1535 strlist__delete(rawlist);
1536
1537 return ret;
1538 }
1539
1540 /* Get current perf-probe event names */
get_probe_trace_event_names(int fd,bool include_group)1541 static struct strlist *get_probe_trace_event_names(int fd, bool include_group)
1542 {
1543 char buf[128];
1544 struct strlist *sl, *rawlist;
1545 struct str_node *ent;
1546 struct probe_trace_event tev;
1547 int ret = 0;
1548
1549 memset(&tev, 0, sizeof(tev));
1550 rawlist = get_probe_trace_command_rawlist(fd);
1551 sl = strlist__new(true, NULL);
1552 strlist__for_each(ent, rawlist) {
1553 ret = parse_probe_trace_command(ent->s, &tev);
1554 if (ret < 0)
1555 break;
1556 if (include_group) {
1557 ret = e_snprintf(buf, 128, "%s:%s", tev.group,
1558 tev.event);
1559 if (ret >= 0)
1560 ret = strlist__add(sl, buf);
1561 } else
1562 ret = strlist__add(sl, tev.event);
1563 clear_probe_trace_event(&tev);
1564 if (ret < 0)
1565 break;
1566 }
1567 strlist__delete(rawlist);
1568
1569 if (ret < 0) {
1570 strlist__delete(sl);
1571 return NULL;
1572 }
1573 return sl;
1574 }
1575
write_probe_trace_event(int fd,struct probe_trace_event * tev)1576 static int write_probe_trace_event(int fd, struct probe_trace_event *tev)
1577 {
1578 int ret = 0;
1579 char *buf = synthesize_probe_trace_command(tev);
1580
1581 if (!buf) {
1582 pr_debug("Failed to synthesize probe trace event.\n");
1583 return -EINVAL;
1584 }
1585
1586 pr_debug("Writing event: %s\n", buf);
1587 if (!probe_event_dry_run) {
1588 ret = write(fd, buf, strlen(buf));
1589 if (ret <= 0)
1590 pr_warning("Failed to write event: %s\n",
1591 strerror(errno));
1592 }
1593 free(buf);
1594 return ret;
1595 }
1596
get_new_event_name(char * buf,size_t len,const char * base,struct strlist * namelist,bool allow_suffix)1597 static int get_new_event_name(char *buf, size_t len, const char *base,
1598 struct strlist *namelist, bool allow_suffix)
1599 {
1600 int i, ret;
1601
1602 /* Try no suffix */
1603 ret = e_snprintf(buf, len, "%s", base);
1604 if (ret < 0) {
1605 pr_debug("snprintf() failed: %s\n", strerror(-ret));
1606 return ret;
1607 }
1608 if (!strlist__has_entry(namelist, buf))
1609 return 0;
1610
1611 if (!allow_suffix) {
1612 pr_warning("Error: event \"%s\" already exists. "
1613 "(Use -f to force duplicates.)\n", base);
1614 return -EEXIST;
1615 }
1616
1617 /* Try to add suffix */
1618 for (i = 1; i < MAX_EVENT_INDEX; i++) {
1619 ret = e_snprintf(buf, len, "%s_%d", base, i);
1620 if (ret < 0) {
1621 pr_debug("snprintf() failed: %s\n", strerror(-ret));
1622 return ret;
1623 }
1624 if (!strlist__has_entry(namelist, buf))
1625 break;
1626 }
1627 if (i == MAX_EVENT_INDEX) {
1628 pr_warning("Too many events are on the same function.\n");
1629 ret = -ERANGE;
1630 }
1631
1632 return ret;
1633 }
1634
__add_probe_trace_events(struct perf_probe_event * pev,struct probe_trace_event * tevs,int ntevs,bool allow_suffix)1635 static int __add_probe_trace_events(struct perf_probe_event *pev,
1636 struct probe_trace_event *tevs,
1637 int ntevs, bool allow_suffix)
1638 {
1639 int i, fd, ret;
1640 struct probe_trace_event *tev = NULL;
1641 char buf[64];
1642 const char *event, *group;
1643 struct strlist *namelist;
1644
1645 fd = open_kprobe_events(true);
1646 if (fd < 0)
1647 return fd;
1648 /* Get current event names */
1649 namelist = get_probe_trace_event_names(fd, false);
1650 if (!namelist) {
1651 pr_debug("Failed to get current event list.\n");
1652 return -EIO;
1653 }
1654
1655 ret = 0;
1656 printf("Add new event%s\n", (ntevs > 1) ? "s:" : ":");
1657 for (i = 0; i < ntevs; i++) {
1658 tev = &tevs[i];
1659 if (pev->event)
1660 event = pev->event;
1661 else
1662 if (pev->point.function)
1663 event = pev->point.function;
1664 else
1665 event = tev->point.symbol;
1666 if (pev->group)
1667 group = pev->group;
1668 else
1669 group = PERFPROBE_GROUP;
1670
1671 /* Get an unused new event name */
1672 ret = get_new_event_name(buf, 64, event,
1673 namelist, allow_suffix);
1674 if (ret < 0)
1675 break;
1676 event = buf;
1677
1678 tev->event = strdup(event);
1679 tev->group = strdup(group);
1680 if (tev->event == NULL || tev->group == NULL) {
1681 ret = -ENOMEM;
1682 break;
1683 }
1684 ret = write_probe_trace_event(fd, tev);
1685 if (ret < 0)
1686 break;
1687 /* Add added event name to namelist */
1688 strlist__add(namelist, event);
1689
1690 /* Trick here - save current event/group */
1691 event = pev->event;
1692 group = pev->group;
1693 pev->event = tev->event;
1694 pev->group = tev->group;
1695 show_perf_probe_event(pev);
1696 /* Trick here - restore current event/group */
1697 pev->event = (char *)event;
1698 pev->group = (char *)group;
1699
1700 /*
1701 * Probes after the first probe which comes from same
1702 * user input are always allowed to add suffix, because
1703 * there might be several addresses corresponding to
1704 * one code line.
1705 */
1706 allow_suffix = true;
1707 }
1708
1709 if (ret >= 0) {
1710 /* Show how to use the event. */
1711 printf("\nYou can now use it on all perf tools, such as:\n\n");
1712 printf("\tperf record -e %s:%s -aR sleep 1\n\n", tev->group,
1713 tev->event);
1714 }
1715
1716 strlist__delete(namelist);
1717 close(fd);
1718 return ret;
1719 }
1720
convert_to_probe_trace_events(struct perf_probe_event * pev,struct probe_trace_event ** tevs,int max_tevs,const char * module)1721 static int convert_to_probe_trace_events(struct perf_probe_event *pev,
1722 struct probe_trace_event **tevs,
1723 int max_tevs, const char *module)
1724 {
1725 struct symbol *sym;
1726 int ret = 0, i;
1727 struct probe_trace_event *tev;
1728
1729 /* Convert perf_probe_event with debuginfo */
1730 ret = try_to_find_probe_trace_events(pev, tevs, max_tevs, module);
1731 if (ret != 0)
1732 return ret;
1733
1734 /* Allocate trace event buffer */
1735 tev = *tevs = zalloc(sizeof(struct probe_trace_event));
1736 if (tev == NULL)
1737 return -ENOMEM;
1738
1739 /* Copy parameters */
1740 tev->point.symbol = strdup(pev->point.function);
1741 if (tev->point.symbol == NULL) {
1742 ret = -ENOMEM;
1743 goto error;
1744 }
1745 tev->point.offset = pev->point.offset;
1746 tev->point.retprobe = pev->point.retprobe;
1747 tev->nargs = pev->nargs;
1748 if (tev->nargs) {
1749 tev->args = zalloc(sizeof(struct probe_trace_arg)
1750 * tev->nargs);
1751 if (tev->args == NULL) {
1752 ret = -ENOMEM;
1753 goto error;
1754 }
1755 for (i = 0; i < tev->nargs; i++) {
1756 if (pev->args[i].name) {
1757 tev->args[i].name = strdup(pev->args[i].name);
1758 if (tev->args[i].name == NULL) {
1759 ret = -ENOMEM;
1760 goto error;
1761 }
1762 }
1763 tev->args[i].value = strdup(pev->args[i].var);
1764 if (tev->args[i].value == NULL) {
1765 ret = -ENOMEM;
1766 goto error;
1767 }
1768 if (pev->args[i].type) {
1769 tev->args[i].type = strdup(pev->args[i].type);
1770 if (tev->args[i].type == NULL) {
1771 ret = -ENOMEM;
1772 goto error;
1773 }
1774 }
1775 }
1776 }
1777
1778 /* Currently just checking function name from symbol map */
1779 sym = __find_kernel_function_by_name(tev->point.symbol, NULL);
1780 if (!sym) {
1781 pr_warning("Kernel symbol \'%s\' not found.\n",
1782 tev->point.symbol);
1783 ret = -ENOENT;
1784 goto error;
1785 }
1786
1787 return 1;
1788 error:
1789 clear_probe_trace_event(tev);
1790 free(tev);
1791 *tevs = NULL;
1792 return ret;
1793 }
1794
1795 struct __event_package {
1796 struct perf_probe_event *pev;
1797 struct probe_trace_event *tevs;
1798 int ntevs;
1799 };
1800
add_perf_probe_events(struct perf_probe_event * pevs,int npevs,int max_tevs,const char * module,bool force_add)1801 int add_perf_probe_events(struct perf_probe_event *pevs, int npevs,
1802 int max_tevs, const char *module, bool force_add)
1803 {
1804 int i, j, ret;
1805 struct __event_package *pkgs;
1806
1807 pkgs = zalloc(sizeof(struct __event_package) * npevs);
1808 if (pkgs == NULL)
1809 return -ENOMEM;
1810
1811 /* Init vmlinux path */
1812 ret = init_vmlinux();
1813 if (ret < 0) {
1814 free(pkgs);
1815 return ret;
1816 }
1817
1818 /* Loop 1: convert all events */
1819 for (i = 0; i < npevs; i++) {
1820 pkgs[i].pev = &pevs[i];
1821 /* Convert with or without debuginfo */
1822 ret = convert_to_probe_trace_events(pkgs[i].pev,
1823 &pkgs[i].tevs,
1824 max_tevs,
1825 module);
1826 if (ret < 0)
1827 goto end;
1828 pkgs[i].ntevs = ret;
1829 }
1830
1831 /* Loop 2: add all events */
1832 for (i = 0; i < npevs; i++) {
1833 ret = __add_probe_trace_events(pkgs[i].pev, pkgs[i].tevs,
1834 pkgs[i].ntevs, force_add);
1835 if (ret < 0)
1836 break;
1837 }
1838 end:
1839 /* Loop 3: cleanup and free trace events */
1840 for (i = 0; i < npevs; i++) {
1841 for (j = 0; j < pkgs[i].ntevs; j++)
1842 clear_probe_trace_event(&pkgs[i].tevs[j]);
1843 free(pkgs[i].tevs);
1844 }
1845 free(pkgs);
1846
1847 return ret;
1848 }
1849
__del_trace_probe_event(int fd,struct str_node * ent)1850 static int __del_trace_probe_event(int fd, struct str_node *ent)
1851 {
1852 char *p;
1853 char buf[128];
1854 int ret;
1855
1856 /* Convert from perf-probe event to trace-probe event */
1857 ret = e_snprintf(buf, 128, "-:%s", ent->s);
1858 if (ret < 0)
1859 goto error;
1860
1861 p = strchr(buf + 2, ':');
1862 if (!p) {
1863 pr_debug("Internal error: %s should have ':' but not.\n",
1864 ent->s);
1865 ret = -ENOTSUP;
1866 goto error;
1867 }
1868 *p = '/';
1869
1870 pr_debug("Writing event: %s\n", buf);
1871 ret = write(fd, buf, strlen(buf));
1872 if (ret < 0)
1873 goto error;
1874
1875 printf("Remove event: %s\n", ent->s);
1876 return 0;
1877 error:
1878 pr_warning("Failed to delete event: %s\n", strerror(-ret));
1879 return ret;
1880 }
1881
del_trace_probe_event(int fd,const char * group,const char * event,struct strlist * namelist)1882 static int del_trace_probe_event(int fd, const char *group,
1883 const char *event, struct strlist *namelist)
1884 {
1885 char buf[128];
1886 struct str_node *ent, *n;
1887 int found = 0, ret = 0;
1888
1889 ret = e_snprintf(buf, 128, "%s:%s", group, event);
1890 if (ret < 0) {
1891 pr_err("Failed to copy event.\n");
1892 return ret;
1893 }
1894
1895 if (strpbrk(buf, "*?")) { /* Glob-exp */
1896 strlist__for_each_safe(ent, n, namelist)
1897 if (strglobmatch(ent->s, buf)) {
1898 found++;
1899 ret = __del_trace_probe_event(fd, ent);
1900 if (ret < 0)
1901 break;
1902 strlist__remove(namelist, ent);
1903 }
1904 } else {
1905 ent = strlist__find(namelist, buf);
1906 if (ent) {
1907 found++;
1908 ret = __del_trace_probe_event(fd, ent);
1909 if (ret >= 0)
1910 strlist__remove(namelist, ent);
1911 }
1912 }
1913 if (found == 0 && ret >= 0)
1914 pr_info("Info: Event \"%s\" does not exist.\n", buf);
1915
1916 return ret;
1917 }
1918
del_perf_probe_events(struct strlist * dellist)1919 int del_perf_probe_events(struct strlist *dellist)
1920 {
1921 int fd, ret = 0;
1922 const char *group, *event;
1923 char *p, *str;
1924 struct str_node *ent;
1925 struct strlist *namelist;
1926
1927 fd = open_kprobe_events(true);
1928 if (fd < 0)
1929 return fd;
1930
1931 /* Get current event names */
1932 namelist = get_probe_trace_event_names(fd, true);
1933 if (namelist == NULL)
1934 return -EINVAL;
1935
1936 strlist__for_each(ent, dellist) {
1937 str = strdup(ent->s);
1938 if (str == NULL) {
1939 ret = -ENOMEM;
1940 break;
1941 }
1942 pr_debug("Parsing: %s\n", str);
1943 p = strchr(str, ':');
1944 if (p) {
1945 group = str;
1946 *p = '\0';
1947 event = p + 1;
1948 } else {
1949 group = "*";
1950 event = str;
1951 }
1952 pr_debug("Group: %s, Event: %s\n", group, event);
1953 ret = del_trace_probe_event(fd, group, event, namelist);
1954 free(str);
1955 if (ret < 0)
1956 break;
1957 }
1958 strlist__delete(namelist);
1959 close(fd);
1960
1961 return ret;
1962 }
1963 /* TODO: don't use a global variable for filter ... */
1964 static struct strfilter *available_func_filter;
1965
1966 /*
1967 * If a symbol corresponds to a function with global binding and
1968 * matches filter return 0. For all others return 1.
1969 */
filter_available_functions(struct map * map __unused,struct symbol * sym)1970 static int filter_available_functions(struct map *map __unused,
1971 struct symbol *sym)
1972 {
1973 if (sym->binding == STB_GLOBAL &&
1974 strfilter__compare(available_func_filter, sym->name))
1975 return 0;
1976 return 1;
1977 }
1978
show_available_funcs(const char * module,struct strfilter * _filter)1979 int show_available_funcs(const char *module, struct strfilter *_filter)
1980 {
1981 struct map *map;
1982 int ret;
1983
1984 setup_pager();
1985
1986 ret = init_vmlinux();
1987 if (ret < 0)
1988 return ret;
1989
1990 map = kernel_get_module_map(module);
1991 if (!map) {
1992 pr_err("Failed to find %s map.\n", (module) ? : "kernel");
1993 return -EINVAL;
1994 }
1995 available_func_filter = _filter;
1996 if (map__load(map, filter_available_functions)) {
1997 pr_err("Failed to load map.\n");
1998 return -EINVAL;
1999 }
2000 if (!dso__sorted_by_name(map->dso, map->type))
2001 dso__sort_by_name(map->dso, map->type);
2002
2003 dso__fprintf_symbols_by_name(map->dso, map->type, stdout);
2004 return 0;
2005 }
2006