]>
Commit | Line | Data |
---|---|---|
1 | // SPDX-License-Identifier: GPL-2.0-or-later | |
2 | /* | |
3 | * probe-file.c : operate ftrace k/uprobe events files | |
4 | * | |
5 | * Written by Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> | |
6 | */ | |
7 | #include <errno.h> | |
8 | #include <fcntl.h> | |
9 | #include <sys/stat.h> | |
10 | #include <sys/types.h> | |
11 | #include <sys/uio.h> | |
12 | #include <unistd.h> | |
13 | #include <linux/zalloc.h> | |
14 | #include "namespaces.h" | |
15 | #include "event.h" | |
16 | #include "strlist.h" | |
17 | #include "strfilter.h" | |
18 | #include "debug.h" | |
19 | #include "build-id.h" | |
20 | #include "dso.h" | |
21 | #include "color.h" | |
22 | #include "symbol.h" | |
23 | #include "strbuf.h" | |
24 | #include <api/fs/tracing_path.h> | |
25 | #include <api/fs/fs.h> | |
26 | #include "probe-event.h" | |
27 | #include "probe-file.h" | |
28 | #include "session.h" | |
29 | #include "perf_regs.h" | |
30 | #include "string2.h" | |
31 | ||
32 | /* 4096 - 2 ('\n' + '\0') */ | |
33 | #define MAX_CMDLEN 4094 | |
34 | ||
35 | static bool print_common_warning(int err, bool readwrite) | |
36 | { | |
37 | if (err == -EACCES) | |
38 | pr_warning("No permission to %s tracefs.\nPlease %s\n", | |
39 | readwrite ? "write" : "read", | |
40 | readwrite ? "run this command again with sudo." : | |
41 | "try 'sudo mount -o remount,mode=755 /sys/kernel/tracing/'"); | |
42 | else | |
43 | return false; | |
44 | ||
45 | return true; | |
46 | } | |
47 | ||
48 | static bool print_configure_probe_event(int kerr, int uerr) | |
49 | { | |
50 | const char *config, *file; | |
51 | ||
52 | if (kerr == -ENOENT && uerr == -ENOENT) { | |
53 | file = "{k,u}probe_events"; | |
54 | config = "CONFIG_KPROBE_EVENTS=y and CONFIG_UPROBE_EVENTS=y"; | |
55 | } else if (kerr == -ENOENT) { | |
56 | file = "kprobe_events"; | |
57 | config = "CONFIG_KPROBE_EVENTS=y"; | |
58 | } else if (uerr == -ENOENT) { | |
59 | file = "uprobe_events"; | |
60 | config = "CONFIG_UPROBE_EVENTS=y"; | |
61 | } else | |
62 | return false; | |
63 | ||
64 | if (!debugfs__configured() && !tracefs__configured()) | |
65 | pr_warning("Debugfs or tracefs is not mounted\n" | |
66 | "Please try 'sudo mount -t tracefs nodev /sys/kernel/tracing/'\n"); | |
67 | else | |
68 | pr_warning("%s/%s does not exist.\nPlease rebuild kernel with %s.\n", | |
69 | tracing_path_mount(), file, config); | |
70 | ||
71 | return true; | |
72 | } | |
73 | ||
74 | static void print_open_warning(int err, bool uprobe, bool readwrite) | |
75 | { | |
76 | char sbuf[STRERR_BUFSIZE]; | |
77 | ||
78 | if (print_common_warning(err, readwrite)) | |
79 | return; | |
80 | ||
81 | if (print_configure_probe_event(uprobe ? 0 : err, uprobe ? err : 0)) | |
82 | return; | |
83 | ||
84 | pr_warning("Failed to open %s/%cprobe_events: %s\n", | |
85 | tracing_path_mount(), uprobe ? 'u' : 'k', | |
86 | str_error_r(-err, sbuf, sizeof(sbuf))); | |
87 | } | |
88 | ||
89 | static void print_both_open_warning(int kerr, int uerr, bool readwrite) | |
90 | { | |
91 | char sbuf[STRERR_BUFSIZE]; | |
92 | ||
93 | if (kerr == uerr && print_common_warning(kerr, readwrite)) | |
94 | return; | |
95 | ||
96 | if (print_configure_probe_event(kerr, uerr)) | |
97 | return; | |
98 | ||
99 | if (kerr < 0) | |
100 | pr_warning("Failed to open %s/kprobe_events: %s.\n", | |
101 | tracing_path_mount(), | |
102 | str_error_r(-kerr, sbuf, sizeof(sbuf))); | |
103 | if (uerr < 0) | |
104 | pr_warning("Failed to open %s/uprobe_events: %s.\n", | |
105 | tracing_path_mount(), | |
106 | str_error_r(-uerr, sbuf, sizeof(sbuf))); | |
107 | } | |
108 | ||
109 | int open_trace_file(const char *trace_file, bool readwrite) | |
110 | { | |
111 | char buf[PATH_MAX]; | |
112 | int ret; | |
113 | ||
114 | ret = e_snprintf(buf, PATH_MAX, "%s/%s", tracing_path_mount(), trace_file); | |
115 | if (ret >= 0) { | |
116 | pr_debug("Opening %s write=%d\n", buf, readwrite); | |
117 | if (readwrite && !probe_event_dry_run) | |
118 | ret = open(buf, O_RDWR | O_APPEND, 0); | |
119 | else | |
120 | ret = open(buf, O_RDONLY, 0); | |
121 | ||
122 | if (ret < 0) | |
123 | ret = -errno; | |
124 | } | |
125 | return ret; | |
126 | } | |
127 | ||
128 | static int open_kprobe_events(bool readwrite) | |
129 | { | |
130 | return open_trace_file("kprobe_events", readwrite); | |
131 | } | |
132 | ||
133 | static int open_uprobe_events(bool readwrite) | |
134 | { | |
135 | return open_trace_file("uprobe_events", readwrite); | |
136 | } | |
137 | ||
138 | int probe_file__open(int flag) | |
139 | { | |
140 | int fd; | |
141 | ||
142 | if (flag & PF_FL_UPROBE) | |
143 | fd = open_uprobe_events(flag & PF_FL_RW); | |
144 | else | |
145 | fd = open_kprobe_events(flag & PF_FL_RW); | |
146 | if (fd < 0) | |
147 | print_open_warning(fd, flag & PF_FL_UPROBE, flag & PF_FL_RW); | |
148 | ||
149 | return fd; | |
150 | } | |
151 | ||
152 | int probe_file__open_both(int *kfd, int *ufd, int flag) | |
153 | { | |
154 | if (!kfd || !ufd) | |
155 | return -EINVAL; | |
156 | ||
157 | *kfd = open_kprobe_events(flag & PF_FL_RW); | |
158 | *ufd = open_uprobe_events(flag & PF_FL_RW); | |
159 | if (*kfd < 0 && *ufd < 0) { | |
160 | print_both_open_warning(*kfd, *ufd, flag & PF_FL_RW); | |
161 | return *kfd; | |
162 | } | |
163 | ||
164 | return 0; | |
165 | } | |
166 | ||
167 | /* Get raw string list of current kprobe_events or uprobe_events */ | |
168 | struct strlist *probe_file__get_rawlist(int fd) | |
169 | { | |
170 | int ret, idx, fddup; | |
171 | FILE *fp; | |
172 | char buf[MAX_CMDLEN]; | |
173 | char *p; | |
174 | struct strlist *sl; | |
175 | ||
176 | if (fd < 0) | |
177 | return NULL; | |
178 | ||
179 | sl = strlist__new(NULL, NULL); | |
180 | if (sl == NULL) | |
181 | return NULL; | |
182 | ||
183 | fddup = dup(fd); | |
184 | if (fddup < 0) | |
185 | goto out_free_sl; | |
186 | ||
187 | fp = fdopen(fddup, "r"); | |
188 | if (!fp) | |
189 | goto out_close_fddup; | |
190 | ||
191 | while (!feof(fp)) { | |
192 | p = fgets(buf, MAX_CMDLEN, fp); | |
193 | if (!p) | |
194 | break; | |
195 | ||
196 | idx = strlen(p) - 1; | |
197 | if (p[idx] == '\n') | |
198 | p[idx] = '\0'; | |
199 | ret = strlist__add(sl, buf); | |
200 | if (ret < 0) { | |
201 | pr_debug("strlist__add failed (%d)\n", ret); | |
202 | goto out_close_fp; | |
203 | } | |
204 | } | |
205 | fclose(fp); | |
206 | ||
207 | return sl; | |
208 | ||
209 | out_close_fp: | |
210 | fclose(fp); | |
211 | goto out_free_sl; | |
212 | out_close_fddup: | |
213 | close(fddup); | |
214 | out_free_sl: | |
215 | strlist__delete(sl); | |
216 | return NULL; | |
217 | } | |
218 | ||
219 | static struct strlist *__probe_file__get_namelist(int fd, bool include_group) | |
220 | { | |
221 | char buf[128]; | |
222 | struct strlist *sl, *rawlist; | |
223 | struct str_node *ent; | |
224 | struct probe_trace_event tev; | |
225 | int ret = 0; | |
226 | ||
227 | memset(&tev, 0, sizeof(tev)); | |
228 | rawlist = probe_file__get_rawlist(fd); | |
229 | if (!rawlist) | |
230 | return NULL; | |
231 | sl = strlist__new(NULL, NULL); | |
232 | strlist__for_each_entry(ent, rawlist) { | |
233 | ret = parse_probe_trace_command(ent->s, &tev); | |
234 | if (ret < 0) | |
235 | break; | |
236 | if (include_group) { | |
237 | ret = e_snprintf(buf, 128, "%s:%s", tev.group, | |
238 | tev.event); | |
239 | if (ret >= 0) | |
240 | ret = strlist__add(sl, buf); | |
241 | } else | |
242 | ret = strlist__add(sl, tev.event); | |
243 | clear_probe_trace_event(&tev); | |
244 | /* Skip if there is same name multi-probe event in the list */ | |
245 | if (ret == -EEXIST) | |
246 | ret = 0; | |
247 | if (ret < 0) | |
248 | break; | |
249 | } | |
250 | strlist__delete(rawlist); | |
251 | ||
252 | if (ret < 0) { | |
253 | strlist__delete(sl); | |
254 | return NULL; | |
255 | } | |
256 | return sl; | |
257 | } | |
258 | ||
259 | /* Get current perf-probe event names */ | |
260 | struct strlist *probe_file__get_namelist(int fd) | |
261 | { | |
262 | return __probe_file__get_namelist(fd, false); | |
263 | } | |
264 | ||
265 | int probe_file__add_event(int fd, struct probe_trace_event *tev) | |
266 | { | |
267 | int ret = 0; | |
268 | char *buf = synthesize_probe_trace_command(tev); | |
269 | char sbuf[STRERR_BUFSIZE]; | |
270 | ||
271 | if (!buf) { | |
272 | pr_debug("Failed to synthesize probe trace event.\n"); | |
273 | return -EINVAL; | |
274 | } | |
275 | ||
276 | pr_debug("Writing event: %s\n", buf); | |
277 | if (!probe_event_dry_run) { | |
278 | if (write(fd, buf, strlen(buf)) < (int)strlen(buf)) { | |
279 | ret = -errno; | |
280 | pr_warning("Failed to write event: %s\n", | |
281 | str_error_r(errno, sbuf, sizeof(sbuf))); | |
282 | } | |
283 | } | |
284 | free(buf); | |
285 | ||
286 | return ret; | |
287 | } | |
288 | ||
289 | static int __del_trace_probe_event(int fd, struct str_node *ent) | |
290 | { | |
291 | char *p; | |
292 | char buf[128]; | |
293 | int ret; | |
294 | ||
295 | /* Convert from perf-probe event to trace-probe event */ | |
296 | ret = e_snprintf(buf, 128, "-:%s", ent->s); | |
297 | if (ret < 0) | |
298 | goto error; | |
299 | ||
300 | p = strchr(buf + 2, ':'); | |
301 | if (!p) { | |
302 | pr_debug("Internal error: %s should have ':' but not.\n", | |
303 | ent->s); | |
304 | ret = -ENOTSUP; | |
305 | goto error; | |
306 | } | |
307 | *p = '/'; | |
308 | ||
309 | pr_debug("Writing event: %s\n", buf); | |
310 | ret = write(fd, buf, strlen(buf)); | |
311 | if (ret < 0) { | |
312 | ret = -errno; | |
313 | goto error; | |
314 | } | |
315 | ||
316 | return 0; | |
317 | error: | |
318 | pr_warning("Failed to delete event: %s\n", | |
319 | str_error_r(-ret, buf, sizeof(buf))); | |
320 | return ret; | |
321 | } | |
322 | ||
323 | int probe_file__get_events(int fd, struct strfilter *filter, | |
324 | struct strlist *plist) | |
325 | { | |
326 | struct strlist *namelist; | |
327 | struct str_node *ent; | |
328 | const char *p; | |
329 | int ret = -ENOENT; | |
330 | ||
331 | if (!plist) | |
332 | return -EINVAL; | |
333 | ||
334 | namelist = __probe_file__get_namelist(fd, true); | |
335 | if (!namelist) | |
336 | return -ENOENT; | |
337 | ||
338 | strlist__for_each_entry(ent, namelist) { | |
339 | p = strchr(ent->s, ':'); | |
340 | if ((p && strfilter__compare(filter, p + 1)) || | |
341 | strfilter__compare(filter, ent->s)) { | |
342 | ret = strlist__add(plist, ent->s); | |
343 | if (ret == -ENOMEM) { | |
344 | pr_err("strlist__add failed with -ENOMEM\n"); | |
345 | goto out; | |
346 | } | |
347 | ret = 0; | |
348 | } | |
349 | } | |
350 | out: | |
351 | strlist__delete(namelist); | |
352 | ||
353 | return ret; | |
354 | } | |
355 | ||
356 | int probe_file__del_strlist(int fd, struct strlist *namelist) | |
357 | { | |
358 | int ret = 0; | |
359 | struct str_node *ent; | |
360 | ||
361 | strlist__for_each_entry(ent, namelist) { | |
362 | ret = __del_trace_probe_event(fd, ent); | |
363 | if (ret < 0) | |
364 | break; | |
365 | } | |
366 | return ret; | |
367 | } | |
368 | ||
369 | int probe_file__del_events(int fd, struct strfilter *filter) | |
370 | { | |
371 | struct strlist *namelist; | |
372 | int ret; | |
373 | ||
374 | namelist = strlist__new(NULL, NULL); | |
375 | if (!namelist) | |
376 | return -ENOMEM; | |
377 | ||
378 | ret = probe_file__get_events(fd, filter, namelist); | |
379 | if (ret < 0) | |
380 | goto out; | |
381 | ||
382 | ret = probe_file__del_strlist(fd, namelist); | |
383 | out: | |
384 | strlist__delete(namelist); | |
385 | return ret; | |
386 | } | |
387 | ||
388 | /* Caller must ensure to remove this entry from list */ | |
389 | static void probe_cache_entry__delete(struct probe_cache_entry *entry) | |
390 | { | |
391 | if (entry) { | |
392 | BUG_ON(!list_empty(&entry->node)); | |
393 | ||
394 | strlist__delete(entry->tevlist); | |
395 | clear_perf_probe_event(&entry->pev); | |
396 | zfree(&entry->spev); | |
397 | free(entry); | |
398 | } | |
399 | } | |
400 | ||
401 | static struct probe_cache_entry * | |
402 | probe_cache_entry__new(struct perf_probe_event *pev) | |
403 | { | |
404 | struct probe_cache_entry *entry = zalloc(sizeof(*entry)); | |
405 | ||
406 | if (entry) { | |
407 | INIT_LIST_HEAD(&entry->node); | |
408 | entry->tevlist = strlist__new(NULL, NULL); | |
409 | if (!entry->tevlist) | |
410 | zfree(&entry); | |
411 | else if (pev) { | |
412 | entry->spev = synthesize_perf_probe_command(pev); | |
413 | if (!entry->spev || | |
414 | perf_probe_event__copy(&entry->pev, pev) < 0) { | |
415 | probe_cache_entry__delete(entry); | |
416 | return NULL; | |
417 | } | |
418 | } | |
419 | } | |
420 | ||
421 | return entry; | |
422 | } | |
423 | ||
424 | int probe_cache_entry__get_event(struct probe_cache_entry *entry, | |
425 | struct probe_trace_event **tevs) | |
426 | { | |
427 | struct probe_trace_event *tev; | |
428 | struct str_node *node; | |
429 | int ret, i; | |
430 | ||
431 | ret = strlist__nr_entries(entry->tevlist); | |
432 | if (ret > probe_conf.max_probes) | |
433 | return -E2BIG; | |
434 | ||
435 | *tevs = zalloc(ret * sizeof(*tev)); | |
436 | if (!*tevs) | |
437 | return -ENOMEM; | |
438 | ||
439 | i = 0; | |
440 | strlist__for_each_entry(node, entry->tevlist) { | |
441 | tev = &(*tevs)[i++]; | |
442 | ret = parse_probe_trace_command(node->s, tev); | |
443 | if (ret < 0) | |
444 | break; | |
445 | } | |
446 | return i; | |
447 | } | |
448 | ||
449 | /* For the kernel probe caches, pass target = NULL or DSO__NAME_KALLSYMS */ | |
450 | static int probe_cache__open(struct probe_cache *pcache, const char *target, | |
451 | struct nsinfo *nsi) | |
452 | { | |
453 | char cpath[PATH_MAX]; | |
454 | char sbuildid[SBUILD_ID_SIZE]; | |
455 | char *dir_name = NULL; | |
456 | bool is_kallsyms = false; | |
457 | int ret, fd; | |
458 | struct nscookie nsc; | |
459 | ||
460 | if (target && build_id_cache__cached(target)) { | |
461 | /* This is a cached buildid */ | |
462 | strlcpy(sbuildid, target, SBUILD_ID_SIZE); | |
463 | dir_name = build_id_cache__linkname(sbuildid, NULL, 0); | |
464 | goto found; | |
465 | } | |
466 | ||
467 | if (!target || !strcmp(target, DSO__NAME_KALLSYMS)) { | |
468 | target = DSO__NAME_KALLSYMS; | |
469 | is_kallsyms = true; | |
470 | ret = sysfs__sprintf_build_id("/", sbuildid); | |
471 | } else { | |
472 | nsinfo__mountns_enter(nsi, &nsc); | |
473 | ret = filename__sprintf_build_id(target, sbuildid); | |
474 | nsinfo__mountns_exit(&nsc); | |
475 | } | |
476 | ||
477 | if (ret < 0) { | |
478 | pr_debug("Failed to get build-id from %s.\n", target); | |
479 | return ret; | |
480 | } | |
481 | ||
482 | /* If we have no buildid cache, make it */ | |
483 | if (!build_id_cache__cached(sbuildid)) { | |
484 | ret = build_id_cache__add_s(sbuildid, target, nsi, | |
485 | is_kallsyms, NULL); | |
486 | if (ret < 0) { | |
487 | pr_debug("Failed to add build-id cache: %s\n", target); | |
488 | return ret; | |
489 | } | |
490 | } | |
491 | ||
492 | dir_name = build_id_cache__cachedir(sbuildid, target, nsi, is_kallsyms, | |
493 | false); | |
494 | found: | |
495 | if (!dir_name) { | |
496 | pr_debug("Failed to get cache from %s\n", target); | |
497 | return -ENOMEM; | |
498 | } | |
499 | ||
500 | snprintf(cpath, PATH_MAX, "%s/probes", dir_name); | |
501 | fd = open(cpath, O_CREAT | O_RDWR, 0644); | |
502 | if (fd < 0) | |
503 | pr_debug("Failed to open cache(%d): %s\n", fd, cpath); | |
504 | free(dir_name); | |
505 | pcache->fd = fd; | |
506 | ||
507 | return fd; | |
508 | } | |
509 | ||
510 | static int probe_cache__load(struct probe_cache *pcache) | |
511 | { | |
512 | struct probe_cache_entry *entry = NULL; | |
513 | char buf[MAX_CMDLEN], *p; | |
514 | int ret = 0, fddup; | |
515 | FILE *fp; | |
516 | ||
517 | fddup = dup(pcache->fd); | |
518 | if (fddup < 0) | |
519 | return -errno; | |
520 | fp = fdopen(fddup, "r"); | |
521 | if (!fp) { | |
522 | close(fddup); | |
523 | return -EINVAL; | |
524 | } | |
525 | ||
526 | while (!feof(fp)) { | |
527 | if (!fgets(buf, MAX_CMDLEN, fp)) | |
528 | break; | |
529 | p = strchr(buf, '\n'); | |
530 | if (p) | |
531 | *p = '\0'; | |
532 | /* #perf_probe_event or %sdt_event */ | |
533 | if (buf[0] == '#' || buf[0] == '%') { | |
534 | entry = probe_cache_entry__new(NULL); | |
535 | if (!entry) { | |
536 | ret = -ENOMEM; | |
537 | goto out; | |
538 | } | |
539 | if (buf[0] == '%') | |
540 | entry->sdt = true; | |
541 | entry->spev = strdup(buf + 1); | |
542 | if (entry->spev) | |
543 | ret = parse_perf_probe_command(buf + 1, | |
544 | &entry->pev); | |
545 | else | |
546 | ret = -ENOMEM; | |
547 | if (ret < 0) { | |
548 | probe_cache_entry__delete(entry); | |
549 | goto out; | |
550 | } | |
551 | list_add_tail(&entry->node, &pcache->entries); | |
552 | } else { /* trace_probe_event */ | |
553 | if (!entry) { | |
554 | ret = -EINVAL; | |
555 | goto out; | |
556 | } | |
557 | ret = strlist__add(entry->tevlist, buf); | |
558 | if (ret == -ENOMEM) { | |
559 | pr_err("strlist__add failed with -ENOMEM\n"); | |
560 | goto out; | |
561 | } | |
562 | } | |
563 | } | |
564 | out: | |
565 | fclose(fp); | |
566 | return ret; | |
567 | } | |
568 | ||
569 | static struct probe_cache *probe_cache__alloc(void) | |
570 | { | |
571 | struct probe_cache *pcache = zalloc(sizeof(*pcache)); | |
572 | ||
573 | if (pcache) { | |
574 | INIT_LIST_HEAD(&pcache->entries); | |
575 | pcache->fd = -EINVAL; | |
576 | } | |
577 | return pcache; | |
578 | } | |
579 | ||
580 | void probe_cache__purge(struct probe_cache *pcache) | |
581 | { | |
582 | struct probe_cache_entry *entry, *n; | |
583 | ||
584 | list_for_each_entry_safe(entry, n, &pcache->entries, node) { | |
585 | list_del_init(&entry->node); | |
586 | probe_cache_entry__delete(entry); | |
587 | } | |
588 | } | |
589 | ||
590 | void probe_cache__delete(struct probe_cache *pcache) | |
591 | { | |
592 | if (!pcache) | |
593 | return; | |
594 | ||
595 | probe_cache__purge(pcache); | |
596 | if (pcache->fd > 0) | |
597 | close(pcache->fd); | |
598 | free(pcache); | |
599 | } | |
600 | ||
601 | struct probe_cache *probe_cache__new(const char *target, struct nsinfo *nsi) | |
602 | { | |
603 | struct probe_cache *pcache = probe_cache__alloc(); | |
604 | int ret; | |
605 | ||
606 | if (!pcache) | |
607 | return NULL; | |
608 | ||
609 | ret = probe_cache__open(pcache, target, nsi); | |
610 | if (ret < 0) { | |
611 | pr_debug("Cache open error: %d\n", ret); | |
612 | goto out_err; | |
613 | } | |
614 | ||
615 | ret = probe_cache__load(pcache); | |
616 | if (ret < 0) { | |
617 | pr_debug("Cache read error: %d\n", ret); | |
618 | goto out_err; | |
619 | } | |
620 | ||
621 | return pcache; | |
622 | ||
623 | out_err: | |
624 | probe_cache__delete(pcache); | |
625 | return NULL; | |
626 | } | |
627 | ||
628 | static bool streql(const char *a, const char *b) | |
629 | { | |
630 | if (a == b) | |
631 | return true; | |
632 | ||
633 | if (!a || !b) | |
634 | return false; | |
635 | ||
636 | return !strcmp(a, b); | |
637 | } | |
638 | ||
639 | struct probe_cache_entry * | |
640 | probe_cache__find(struct probe_cache *pcache, struct perf_probe_event *pev) | |
641 | { | |
642 | struct probe_cache_entry *entry = NULL; | |
643 | char *cmd = synthesize_perf_probe_command(pev); | |
644 | ||
645 | if (!cmd) | |
646 | return NULL; | |
647 | ||
648 | for_each_probe_cache_entry(entry, pcache) { | |
649 | if (pev->sdt) { | |
650 | if (entry->pev.event && | |
651 | streql(entry->pev.event, pev->event) && | |
652 | (!pev->group || | |
653 | streql(entry->pev.group, pev->group))) | |
654 | goto found; | |
655 | ||
656 | continue; | |
657 | } | |
658 | /* Hit if same event name or same command-string */ | |
659 | if ((pev->event && | |
660 | (streql(entry->pev.group, pev->group) && | |
661 | streql(entry->pev.event, pev->event))) || | |
662 | (!strcmp(entry->spev, cmd))) | |
663 | goto found; | |
664 | } | |
665 | entry = NULL; | |
666 | ||
667 | found: | |
668 | free(cmd); | |
669 | return entry; | |
670 | } | |
671 | ||
672 | struct probe_cache_entry * | |
673 | probe_cache__find_by_name(struct probe_cache *pcache, | |
674 | const char *group, const char *event) | |
675 | { | |
676 | struct probe_cache_entry *entry = NULL; | |
677 | ||
678 | for_each_probe_cache_entry(entry, pcache) { | |
679 | /* Hit if same event name or same command-string */ | |
680 | if (streql(entry->pev.group, group) && | |
681 | streql(entry->pev.event, event)) | |
682 | goto found; | |
683 | } | |
684 | entry = NULL; | |
685 | ||
686 | found: | |
687 | return entry; | |
688 | } | |
689 | ||
690 | int probe_cache__add_entry(struct probe_cache *pcache, | |
691 | struct perf_probe_event *pev, | |
692 | struct probe_trace_event *tevs, int ntevs) | |
693 | { | |
694 | struct probe_cache_entry *entry = NULL; | |
695 | char *command; | |
696 | int i, ret = 0; | |
697 | ||
698 | if (!pcache || !pev || !tevs || ntevs <= 0) { | |
699 | ret = -EINVAL; | |
700 | goto out_err; | |
701 | } | |
702 | ||
703 | /* Remove old cache entry */ | |
704 | entry = probe_cache__find(pcache, pev); | |
705 | if (entry) { | |
706 | list_del_init(&entry->node); | |
707 | probe_cache_entry__delete(entry); | |
708 | } | |
709 | ||
710 | ret = -ENOMEM; | |
711 | entry = probe_cache_entry__new(pev); | |
712 | if (!entry) | |
713 | goto out_err; | |
714 | ||
715 | for (i = 0; i < ntevs; i++) { | |
716 | if (!tevs[i].point.symbol) | |
717 | continue; | |
718 | ||
719 | command = synthesize_probe_trace_command(&tevs[i]); | |
720 | if (!command) | |
721 | goto out_err; | |
722 | ret = strlist__add(entry->tevlist, command); | |
723 | if (ret == -ENOMEM) { | |
724 | pr_err("strlist__add failed with -ENOMEM\n"); | |
725 | goto out_err; | |
726 | } | |
727 | ||
728 | free(command); | |
729 | } | |
730 | list_add_tail(&entry->node, &pcache->entries); | |
731 | pr_debug("Added probe cache: %d\n", ntevs); | |
732 | return 0; | |
733 | ||
734 | out_err: | |
735 | pr_debug("Failed to add probe caches\n"); | |
736 | probe_cache_entry__delete(entry); | |
737 | return ret; | |
738 | } | |
739 | ||
740 | #ifdef HAVE_GELF_GETNOTE_SUPPORT | |
741 | static unsigned long long sdt_note__get_addr(struct sdt_note *note) | |
742 | { | |
743 | return note->bit32 ? | |
744 | (unsigned long long)note->addr.a32[SDT_NOTE_IDX_LOC] : | |
745 | (unsigned long long)note->addr.a64[SDT_NOTE_IDX_LOC]; | |
746 | } | |
747 | ||
748 | static unsigned long long sdt_note__get_ref_ctr_offset(struct sdt_note *note) | |
749 | { | |
750 | return note->bit32 ? | |
751 | (unsigned long long)note->addr.a32[SDT_NOTE_IDX_REFCTR] : | |
752 | (unsigned long long)note->addr.a64[SDT_NOTE_IDX_REFCTR]; | |
753 | } | |
754 | ||
755 | static const char * const type_to_suffix[] = { | |
756 | ":s64", "", "", "", ":s32", "", ":s16", ":s8", | |
757 | "", ":u8", ":u16", "", ":u32", "", "", "", ":u64" | |
758 | }; | |
759 | ||
760 | /* | |
761 | * Isolate the string number and convert it into a decimal value; | |
762 | * this will be an index to get suffix of the uprobe name (defining | |
763 | * the type) | |
764 | */ | |
765 | static int sdt_arg_parse_size(char *n_ptr, const char **suffix) | |
766 | { | |
767 | long type_idx; | |
768 | ||
769 | type_idx = strtol(n_ptr, NULL, 10); | |
770 | if (type_idx < -8 || type_idx > 8) { | |
771 | pr_debug4("Failed to get a valid sdt type\n"); | |
772 | return -1; | |
773 | } | |
774 | ||
775 | *suffix = type_to_suffix[type_idx + 8]; | |
776 | return 0; | |
777 | } | |
778 | ||
779 | static int synthesize_sdt_probe_arg(struct strbuf *buf, int i, const char *arg) | |
780 | { | |
781 | char *op, *desc = strdup(arg), *new_op = NULL; | |
782 | const char *suffix = ""; | |
783 | int ret = -1; | |
784 | ||
785 | if (desc == NULL) { | |
786 | pr_debug4("Allocation error\n"); | |
787 | return ret; | |
788 | } | |
789 | ||
790 | /* | |
791 | * Argument is in N@OP format. N is size of the argument and OP is | |
792 | * the actual assembly operand. N can be omitted; in that case | |
793 | * argument is just OP(without @). | |
794 | */ | |
795 | op = strchr(desc, '@'); | |
796 | if (op) { | |
797 | op[0] = '\0'; | |
798 | op++; | |
799 | ||
800 | if (sdt_arg_parse_size(desc, &suffix)) | |
801 | goto error; | |
802 | } else { | |
803 | op = desc; | |
804 | } | |
805 | ||
806 | ret = arch_sdt_arg_parse_op(op, &new_op); | |
807 | ||
808 | if (ret < 0) | |
809 | goto error; | |
810 | ||
811 | if (ret == SDT_ARG_VALID) { | |
812 | ret = strbuf_addf(buf, " arg%d=%s%s", i + 1, new_op, suffix); | |
813 | if (ret < 0) | |
814 | goto error; | |
815 | } | |
816 | ||
817 | ret = 0; | |
818 | error: | |
819 | free(desc); | |
820 | free(new_op); | |
821 | return ret; | |
822 | } | |
823 | ||
824 | static char *synthesize_sdt_probe_command(struct sdt_note *note, | |
825 | const char *pathname, | |
826 | const char *sdtgrp) | |
827 | { | |
828 | struct strbuf buf; | |
829 | char *ret = NULL; | |
830 | int i, args_count, err; | |
831 | unsigned long long ref_ctr_offset; | |
832 | char *arg; | |
833 | int arg_idx = 0; | |
834 | ||
835 | if (strbuf_init(&buf, 32) < 0) | |
836 | return NULL; | |
837 | ||
838 | err = strbuf_addf(&buf, "p:%s/%s %s:0x%llx", | |
839 | sdtgrp, note->name, pathname, | |
840 | sdt_note__get_addr(note)); | |
841 | ||
842 | ref_ctr_offset = sdt_note__get_ref_ctr_offset(note); | |
843 | if (ref_ctr_offset && err >= 0) | |
844 | err = strbuf_addf(&buf, "(0x%llx)", ref_ctr_offset); | |
845 | ||
846 | if (err < 0) | |
847 | goto error; | |
848 | ||
849 | if (!note->args) | |
850 | goto out; | |
851 | ||
852 | if (note->args) { | |
853 | char **args = argv_split(note->args, &args_count); | |
854 | ||
855 | if (args == NULL) | |
856 | goto error; | |
857 | ||
858 | for (i = 0; i < args_count; ) { | |
859 | /* | |
860 | * FIXUP: Arm64 ELF section '.note.stapsdt' uses string | |
861 | * format "-4@[sp, NUM]" if a probe is to access data in | |
862 | * the stack, e.g. below is an example for the SDT | |
863 | * Arguments: | |
864 | * | |
865 | * Arguments: -4@[sp, 12] -4@[sp, 8] -4@[sp, 4] | |
866 | * | |
867 | * Since the string introduces an extra space character | |
868 | * in the middle of square brackets, the argument is | |
869 | * divided into two items. Fixup for this case, if an | |
870 | * item contains sub string "[sp,", need to concatenate | |
871 | * the two items. | |
872 | */ | |
873 | if (strstr(args[i], "[sp,") && (i+1) < args_count) { | |
874 | err = asprintf(&arg, "%s %s", args[i], args[i+1]); | |
875 | i += 2; | |
876 | } else { | |
877 | err = asprintf(&arg, "%s", args[i]); | |
878 | i += 1; | |
879 | } | |
880 | ||
881 | /* Failed to allocate memory */ | |
882 | if (err < 0) { | |
883 | argv_free(args); | |
884 | goto error; | |
885 | } | |
886 | ||
887 | if (synthesize_sdt_probe_arg(&buf, arg_idx, arg) < 0) { | |
888 | free(arg); | |
889 | argv_free(args); | |
890 | goto error; | |
891 | } | |
892 | ||
893 | free(arg); | |
894 | arg_idx++; | |
895 | } | |
896 | ||
897 | argv_free(args); | |
898 | } | |
899 | ||
900 | out: | |
901 | ret = strbuf_detach(&buf, NULL); | |
902 | error: | |
903 | strbuf_release(&buf); | |
904 | return ret; | |
905 | } | |
906 | ||
907 | int probe_cache__scan_sdt(struct probe_cache *pcache, const char *pathname) | |
908 | { | |
909 | struct probe_cache_entry *entry = NULL; | |
910 | struct list_head sdtlist; | |
911 | struct sdt_note *note; | |
912 | char *buf; | |
913 | char sdtgrp[64]; | |
914 | int ret; | |
915 | ||
916 | INIT_LIST_HEAD(&sdtlist); | |
917 | ret = get_sdt_note_list(&sdtlist, pathname); | |
918 | if (ret < 0) { | |
919 | pr_debug4("Failed to get sdt note: %d\n", ret); | |
920 | return ret; | |
921 | } | |
922 | list_for_each_entry(note, &sdtlist, note_list) { | |
923 | ret = snprintf(sdtgrp, 64, "sdt_%s", note->provider); | |
924 | if (ret < 0) | |
925 | break; | |
926 | /* Try to find same-name entry */ | |
927 | entry = probe_cache__find_by_name(pcache, sdtgrp, note->name); | |
928 | if (!entry) { | |
929 | entry = probe_cache_entry__new(NULL); | |
930 | if (!entry) { | |
931 | ret = -ENOMEM; | |
932 | break; | |
933 | } | |
934 | entry->sdt = true; | |
935 | ret = asprintf(&entry->spev, "%s:%s=%s", sdtgrp, | |
936 | note->name, note->name); | |
937 | if (ret < 0) | |
938 | break; | |
939 | entry->pev.event = strdup(note->name); | |
940 | entry->pev.group = strdup(sdtgrp); | |
941 | list_add_tail(&entry->node, &pcache->entries); | |
942 | } | |
943 | buf = synthesize_sdt_probe_command(note, pathname, sdtgrp); | |
944 | if (!buf) { | |
945 | ret = -ENOMEM; | |
946 | break; | |
947 | } | |
948 | ||
949 | ret = strlist__add(entry->tevlist, buf); | |
950 | ||
951 | free(buf); | |
952 | entry = NULL; | |
953 | ||
954 | if (ret == -ENOMEM) { | |
955 | pr_err("strlist__add failed with -ENOMEM\n"); | |
956 | break; | |
957 | } | |
958 | } | |
959 | if (entry) { | |
960 | list_del_init(&entry->node); | |
961 | probe_cache_entry__delete(entry); | |
962 | } | |
963 | cleanup_sdt_note_list(&sdtlist); | |
964 | return ret; | |
965 | } | |
966 | #endif | |
967 | ||
968 | static int probe_cache_entry__write(struct probe_cache_entry *entry, int fd) | |
969 | { | |
970 | struct str_node *snode; | |
971 | struct stat st; | |
972 | struct iovec iov[3]; | |
973 | const char *prefix = entry->sdt ? "%" : "#"; | |
974 | int ret; | |
975 | /* Save stat for rollback */ | |
976 | ret = fstat(fd, &st); | |
977 | if (ret < 0) | |
978 | return ret; | |
979 | ||
980 | pr_debug("Writing cache: %s%s\n", prefix, entry->spev); | |
981 | iov[0].iov_base = (void *)prefix; iov[0].iov_len = 1; | |
982 | iov[1].iov_base = entry->spev; iov[1].iov_len = strlen(entry->spev); | |
983 | iov[2].iov_base = (void *)"\n"; iov[2].iov_len = 1; | |
984 | ret = writev(fd, iov, 3); | |
985 | if (ret < (int)iov[1].iov_len + 2) | |
986 | goto rollback; | |
987 | ||
988 | strlist__for_each_entry(snode, entry->tevlist) { | |
989 | iov[0].iov_base = (void *)snode->s; | |
990 | iov[0].iov_len = strlen(snode->s); | |
991 | iov[1].iov_base = (void *)"\n"; iov[1].iov_len = 1; | |
992 | ret = writev(fd, iov, 2); | |
993 | if (ret < (int)iov[0].iov_len + 1) | |
994 | goto rollback; | |
995 | } | |
996 | return 0; | |
997 | ||
998 | rollback: | |
999 | /* Rollback to avoid cache file corruption */ | |
1000 | if (ret > 0) | |
1001 | ret = -1; | |
1002 | if (ftruncate(fd, st.st_size) < 0) | |
1003 | ret = -2; | |
1004 | ||
1005 | return ret; | |
1006 | } | |
1007 | ||
1008 | int probe_cache__commit(struct probe_cache *pcache) | |
1009 | { | |
1010 | struct probe_cache_entry *entry; | |
1011 | int ret = 0; | |
1012 | ||
1013 | /* TBD: if we do not update existing entries, skip it */ | |
1014 | ret = lseek(pcache->fd, 0, SEEK_SET); | |
1015 | if (ret < 0) | |
1016 | goto out; | |
1017 | ||
1018 | ret = ftruncate(pcache->fd, 0); | |
1019 | if (ret < 0) | |
1020 | goto out; | |
1021 | ||
1022 | for_each_probe_cache_entry(entry, pcache) { | |
1023 | ret = probe_cache_entry__write(entry, pcache->fd); | |
1024 | pr_debug("Cache committed: %d\n", ret); | |
1025 | if (ret < 0) | |
1026 | break; | |
1027 | } | |
1028 | out: | |
1029 | return ret; | |
1030 | } | |
1031 | ||
1032 | static bool probe_cache_entry__compare(struct probe_cache_entry *entry, | |
1033 | struct strfilter *filter) | |
1034 | { | |
1035 | char buf[128], *ptr = entry->spev; | |
1036 | ||
1037 | if (entry->pev.event) { | |
1038 | snprintf(buf, 128, "%s:%s", entry->pev.group, entry->pev.event); | |
1039 | ptr = buf; | |
1040 | } | |
1041 | return strfilter__compare(filter, ptr); | |
1042 | } | |
1043 | ||
1044 | int probe_cache__filter_purge(struct probe_cache *pcache, | |
1045 | struct strfilter *filter) | |
1046 | { | |
1047 | struct probe_cache_entry *entry, *tmp; | |
1048 | ||
1049 | list_for_each_entry_safe(entry, tmp, &pcache->entries, node) { | |
1050 | if (probe_cache_entry__compare(entry, filter)) { | |
1051 | pr_info("Removed cached event: %s\n", entry->spev); | |
1052 | list_del_init(&entry->node); | |
1053 | probe_cache_entry__delete(entry); | |
1054 | } | |
1055 | } | |
1056 | return 0; | |
1057 | } | |
1058 | ||
1059 | static int probe_cache__show_entries(struct probe_cache *pcache, | |
1060 | struct strfilter *filter) | |
1061 | { | |
1062 | struct probe_cache_entry *entry; | |
1063 | ||
1064 | for_each_probe_cache_entry(entry, pcache) { | |
1065 | if (probe_cache_entry__compare(entry, filter)) | |
1066 | printf("%s\n", entry->spev); | |
1067 | } | |
1068 | return 0; | |
1069 | } | |
1070 | ||
1071 | /* Show all cached probes */ | |
1072 | int probe_cache__show_all_caches(struct strfilter *filter) | |
1073 | { | |
1074 | struct probe_cache *pcache; | |
1075 | struct strlist *bidlist; | |
1076 | struct str_node *nd; | |
1077 | char *buf = strfilter__string(filter); | |
1078 | ||
1079 | pr_debug("list cache with filter: %s\n", buf); | |
1080 | free(buf); | |
1081 | ||
1082 | bidlist = build_id_cache__list_all(true); | |
1083 | if (!bidlist) { | |
1084 | pr_debug("Failed to get buildids: %d\n", errno); | |
1085 | return -EINVAL; | |
1086 | } | |
1087 | strlist__for_each_entry(nd, bidlist) { | |
1088 | pcache = probe_cache__new(nd->s, NULL); | |
1089 | if (!pcache) | |
1090 | continue; | |
1091 | if (!list_empty(&pcache->entries)) { | |
1092 | buf = build_id_cache__origname(nd->s); | |
1093 | printf("%s (%s):\n", buf, nd->s); | |
1094 | free(buf); | |
1095 | probe_cache__show_entries(pcache, filter); | |
1096 | } | |
1097 | probe_cache__delete(pcache); | |
1098 | } | |
1099 | strlist__delete(bidlist); | |
1100 | ||
1101 | return 0; | |
1102 | } | |
1103 | ||
1104 | enum ftrace_readme { | |
1105 | FTRACE_README_PROBE_TYPE_X = 0, | |
1106 | FTRACE_README_KRETPROBE_OFFSET, | |
1107 | FTRACE_README_UPROBE_REF_CTR, | |
1108 | FTRACE_README_USER_ACCESS, | |
1109 | FTRACE_README_MULTIPROBE_EVENT, | |
1110 | FTRACE_README_IMMEDIATE_VALUE, | |
1111 | FTRACE_README_END, | |
1112 | }; | |
1113 | ||
1114 | static struct { | |
1115 | const char *pattern; | |
1116 | bool avail; | |
1117 | } ftrace_readme_table[] = { | |
1118 | #define DEFINE_TYPE(idx, pat) \ | |
1119 | [idx] = {.pattern = pat, .avail = false} | |
1120 | DEFINE_TYPE(FTRACE_README_PROBE_TYPE_X, "*type: * x8/16/32/64,*"), | |
1121 | DEFINE_TYPE(FTRACE_README_KRETPROBE_OFFSET, "*place (kretprobe): *"), | |
1122 | DEFINE_TYPE(FTRACE_README_UPROBE_REF_CTR, "*ref_ctr_offset*"), | |
1123 | DEFINE_TYPE(FTRACE_README_USER_ACCESS, "*u]<offset>*"), | |
1124 | DEFINE_TYPE(FTRACE_README_MULTIPROBE_EVENT, "*Create/append/*"), | |
1125 | DEFINE_TYPE(FTRACE_README_IMMEDIATE_VALUE, "*\\imm-value,*"), | |
1126 | }; | |
1127 | ||
1128 | static bool scan_ftrace_readme(enum ftrace_readme type) | |
1129 | { | |
1130 | int fd; | |
1131 | FILE *fp; | |
1132 | char *buf = NULL; | |
1133 | size_t len = 0; | |
1134 | bool ret = false; | |
1135 | static bool scanned = false; | |
1136 | ||
1137 | if (scanned) | |
1138 | goto result; | |
1139 | ||
1140 | fd = open_trace_file("README", false); | |
1141 | if (fd < 0) | |
1142 | return ret; | |
1143 | ||
1144 | fp = fdopen(fd, "r"); | |
1145 | if (!fp) { | |
1146 | close(fd); | |
1147 | return ret; | |
1148 | } | |
1149 | ||
1150 | while (getline(&buf, &len, fp) > 0) | |
1151 | for (enum ftrace_readme i = 0; i < FTRACE_README_END; i++) | |
1152 | if (!ftrace_readme_table[i].avail) | |
1153 | ftrace_readme_table[i].avail = | |
1154 | strglobmatch(buf, ftrace_readme_table[i].pattern); | |
1155 | scanned = true; | |
1156 | ||
1157 | fclose(fp); | |
1158 | free(buf); | |
1159 | ||
1160 | result: | |
1161 | if (type >= FTRACE_README_END) | |
1162 | return false; | |
1163 | ||
1164 | return ftrace_readme_table[type].avail; | |
1165 | } | |
1166 | ||
1167 | bool probe_type_is_available(enum probe_type type) | |
1168 | { | |
1169 | if (type >= PROBE_TYPE_END) | |
1170 | return false; | |
1171 | else if (type == PROBE_TYPE_X) | |
1172 | return scan_ftrace_readme(FTRACE_README_PROBE_TYPE_X); | |
1173 | ||
1174 | return true; | |
1175 | } | |
1176 | ||
1177 | bool kretprobe_offset_is_supported(void) | |
1178 | { | |
1179 | return scan_ftrace_readme(FTRACE_README_KRETPROBE_OFFSET); | |
1180 | } | |
1181 | ||
1182 | bool uprobe_ref_ctr_is_supported(void) | |
1183 | { | |
1184 | return scan_ftrace_readme(FTRACE_README_UPROBE_REF_CTR); | |
1185 | } | |
1186 | ||
1187 | bool user_access_is_supported(void) | |
1188 | { | |
1189 | return scan_ftrace_readme(FTRACE_README_USER_ACCESS); | |
1190 | } | |
1191 | ||
1192 | bool multiprobe_event_is_supported(void) | |
1193 | { | |
1194 | return scan_ftrace_readme(FTRACE_README_MULTIPROBE_EVENT); | |
1195 | } | |
1196 | ||
1197 | bool immediate_value_is_supported(void) | |
1198 | { | |
1199 | return scan_ftrace_readme(FTRACE_README_IMMEDIATE_VALUE); | |
1200 | } |