xref: /linux/tools/perf/util/probe-file.c (revision 071bf69a0220253a44acb8b2a27f7a262b9a46bf)
1 /*
2  * probe-file.c : operate ftrace k/uprobe events files
3  *
4  * Written by Masami Hiramatsu <masami.hiramatsu.pt@hitachi.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  */
17 #include <sys/uio.h>
18 #include "util.h"
19 #include "event.h"
20 #include "strlist.h"
21 #include "debug.h"
22 #include "cache.h"
23 #include "color.h"
24 #include "symbol.h"
25 #include "thread.h"
26 #include <api/fs/tracing_path.h>
27 #include "probe-event.h"
28 #include "probe-file.h"
29 #include "session.h"
30 
31 #define MAX_CMDLEN 256
32 
33 static void print_open_warning(int err, bool uprobe)
34 {
35 	char sbuf[STRERR_BUFSIZE];
36 
37 	if (err == -ENOENT) {
38 		const char *config;
39 
40 		if (uprobe)
41 			config = "CONFIG_UPROBE_EVENTS";
42 		else
43 			config = "CONFIG_KPROBE_EVENTS";
44 
45 		pr_warning("%cprobe_events file does not exist"
46 			   " - please rebuild kernel with %s.\n",
47 			   uprobe ? 'u' : 'k', config);
48 	} else if (err == -ENOTSUP)
49 		pr_warning("Tracefs or debugfs is not mounted.\n");
50 	else
51 		pr_warning("Failed to open %cprobe_events: %s\n",
52 			   uprobe ? 'u' : 'k',
53 			   str_error_r(-err, sbuf, sizeof(sbuf)));
54 }
55 
56 static void print_both_open_warning(int kerr, int uerr)
57 {
58 	/* Both kprobes and uprobes are disabled, warn it. */
59 	if (kerr == -ENOTSUP && uerr == -ENOTSUP)
60 		pr_warning("Tracefs or debugfs is not mounted.\n");
61 	else if (kerr == -ENOENT && uerr == -ENOENT)
62 		pr_warning("Please rebuild kernel with CONFIG_KPROBE_EVENTS "
63 			   "or/and CONFIG_UPROBE_EVENTS.\n");
64 	else {
65 		char sbuf[STRERR_BUFSIZE];
66 		pr_warning("Failed to open kprobe events: %s.\n",
67 			   str_error_r(-kerr, sbuf, sizeof(sbuf)));
68 		pr_warning("Failed to open uprobe events: %s.\n",
69 			   str_error_r(-uerr, sbuf, sizeof(sbuf)));
70 	}
71 }
72 
73 static int open_probe_events(const char *trace_file, bool readwrite)
74 {
75 	char buf[PATH_MAX];
76 	const char *tracing_dir = "";
77 	int ret;
78 
79 	ret = e_snprintf(buf, PATH_MAX, "%s/%s%s",
80 			 tracing_path, tracing_dir, trace_file);
81 	if (ret >= 0) {
82 		pr_debug("Opening %s write=%d\n", buf, readwrite);
83 		if (readwrite && !probe_event_dry_run)
84 			ret = open(buf, O_RDWR | O_APPEND, 0);
85 		else
86 			ret = open(buf, O_RDONLY, 0);
87 
88 		if (ret < 0)
89 			ret = -errno;
90 	}
91 	return ret;
92 }
93 
94 static int open_kprobe_events(bool readwrite)
95 {
96 	return open_probe_events("kprobe_events", readwrite);
97 }
98 
99 static int open_uprobe_events(bool readwrite)
100 {
101 	return open_probe_events("uprobe_events", readwrite);
102 }
103 
104 int probe_file__open(int flag)
105 {
106 	int fd;
107 
108 	if (flag & PF_FL_UPROBE)
109 		fd = open_uprobe_events(flag & PF_FL_RW);
110 	else
111 		fd = open_kprobe_events(flag & PF_FL_RW);
112 	if (fd < 0)
113 		print_open_warning(fd, flag & PF_FL_UPROBE);
114 
115 	return fd;
116 }
117 
118 int probe_file__open_both(int *kfd, int *ufd, int flag)
119 {
120 	if (!kfd || !ufd)
121 		return -EINVAL;
122 
123 	*kfd = open_kprobe_events(flag & PF_FL_RW);
124 	*ufd = open_uprobe_events(flag & PF_FL_RW);
125 	if (*kfd < 0 && *ufd < 0) {
126 		print_both_open_warning(*kfd, *ufd);
127 		return *kfd;
128 	}
129 
130 	return 0;
131 }
132 
133 /* Get raw string list of current kprobe_events  or uprobe_events */
134 struct strlist *probe_file__get_rawlist(int fd)
135 {
136 	int ret, idx;
137 	FILE *fp;
138 	char buf[MAX_CMDLEN];
139 	char *p;
140 	struct strlist *sl;
141 
142 	if (fd < 0)
143 		return NULL;
144 
145 	sl = strlist__new(NULL, NULL);
146 
147 	fp = fdopen(dup(fd), "r");
148 	while (!feof(fp)) {
149 		p = fgets(buf, MAX_CMDLEN, fp);
150 		if (!p)
151 			break;
152 
153 		idx = strlen(p) - 1;
154 		if (p[idx] == '\n')
155 			p[idx] = '\0';
156 		ret = strlist__add(sl, buf);
157 		if (ret < 0) {
158 			pr_debug("strlist__add failed (%d)\n", ret);
159 			strlist__delete(sl);
160 			return NULL;
161 		}
162 	}
163 	fclose(fp);
164 
165 	return sl;
166 }
167 
168 static struct strlist *__probe_file__get_namelist(int fd, bool include_group)
169 {
170 	char buf[128];
171 	struct strlist *sl, *rawlist;
172 	struct str_node *ent;
173 	struct probe_trace_event tev;
174 	int ret = 0;
175 
176 	memset(&tev, 0, sizeof(tev));
177 	rawlist = probe_file__get_rawlist(fd);
178 	if (!rawlist)
179 		return NULL;
180 	sl = strlist__new(NULL, NULL);
181 	strlist__for_each_entry(ent, rawlist) {
182 		ret = parse_probe_trace_command(ent->s, &tev);
183 		if (ret < 0)
184 			break;
185 		if (include_group) {
186 			ret = e_snprintf(buf, 128, "%s:%s", tev.group,
187 					tev.event);
188 			if (ret >= 0)
189 				ret = strlist__add(sl, buf);
190 		} else
191 			ret = strlist__add(sl, tev.event);
192 		clear_probe_trace_event(&tev);
193 		if (ret < 0)
194 			break;
195 	}
196 	strlist__delete(rawlist);
197 
198 	if (ret < 0) {
199 		strlist__delete(sl);
200 		return NULL;
201 	}
202 	return sl;
203 }
204 
205 /* Get current perf-probe event names */
206 struct strlist *probe_file__get_namelist(int fd)
207 {
208 	return __probe_file__get_namelist(fd, false);
209 }
210 
211 int probe_file__add_event(int fd, struct probe_trace_event *tev)
212 {
213 	int ret = 0;
214 	char *buf = synthesize_probe_trace_command(tev);
215 	char sbuf[STRERR_BUFSIZE];
216 
217 	if (!buf) {
218 		pr_debug("Failed to synthesize probe trace event.\n");
219 		return -EINVAL;
220 	}
221 
222 	pr_debug("Writing event: %s\n", buf);
223 	if (!probe_event_dry_run) {
224 		if (write(fd, buf, strlen(buf)) < (int)strlen(buf)) {
225 			ret = -errno;
226 			pr_warning("Failed to write event: %s\n",
227 				   str_error_r(errno, sbuf, sizeof(sbuf)));
228 		}
229 	}
230 	free(buf);
231 
232 	return ret;
233 }
234 
235 static int __del_trace_probe_event(int fd, struct str_node *ent)
236 {
237 	char *p;
238 	char buf[128];
239 	int ret;
240 
241 	/* Convert from perf-probe event to trace-probe event */
242 	ret = e_snprintf(buf, 128, "-:%s", ent->s);
243 	if (ret < 0)
244 		goto error;
245 
246 	p = strchr(buf + 2, ':');
247 	if (!p) {
248 		pr_debug("Internal error: %s should have ':' but not.\n",
249 			 ent->s);
250 		ret = -ENOTSUP;
251 		goto error;
252 	}
253 	*p = '/';
254 
255 	pr_debug("Writing event: %s\n", buf);
256 	ret = write(fd, buf, strlen(buf));
257 	if (ret < 0) {
258 		ret = -errno;
259 		goto error;
260 	}
261 
262 	return 0;
263 error:
264 	pr_warning("Failed to delete event: %s\n",
265 		   str_error_r(-ret, buf, sizeof(buf)));
266 	return ret;
267 }
268 
269 int probe_file__get_events(int fd, struct strfilter *filter,
270 			   struct strlist *plist)
271 {
272 	struct strlist *namelist;
273 	struct str_node *ent;
274 	const char *p;
275 	int ret = -ENOENT;
276 
277 	if (!plist)
278 		return -EINVAL;
279 
280 	namelist = __probe_file__get_namelist(fd, true);
281 	if (!namelist)
282 		return -ENOENT;
283 
284 	strlist__for_each_entry(ent, namelist) {
285 		p = strchr(ent->s, ':');
286 		if ((p && strfilter__compare(filter, p + 1)) ||
287 		    strfilter__compare(filter, ent->s)) {
288 			strlist__add(plist, ent->s);
289 			ret = 0;
290 		}
291 	}
292 	strlist__delete(namelist);
293 
294 	return ret;
295 }
296 
297 int probe_file__del_strlist(int fd, struct strlist *namelist)
298 {
299 	int ret = 0;
300 	struct str_node *ent;
301 
302 	strlist__for_each_entry(ent, namelist) {
303 		ret = __del_trace_probe_event(fd, ent);
304 		if (ret < 0)
305 			break;
306 	}
307 	return ret;
308 }
309 
310 int probe_file__del_events(int fd, struct strfilter *filter)
311 {
312 	struct strlist *namelist;
313 	int ret;
314 
315 	namelist = strlist__new(NULL, NULL);
316 	if (!namelist)
317 		return -ENOMEM;
318 
319 	ret = probe_file__get_events(fd, filter, namelist);
320 	if (ret < 0)
321 		return ret;
322 
323 	ret = probe_file__del_strlist(fd, namelist);
324 	strlist__delete(namelist);
325 
326 	return ret;
327 }
328 
329 /* Caller must ensure to remove this entry from list */
330 static void probe_cache_entry__delete(struct probe_cache_entry *entry)
331 {
332 	if (entry) {
333 		BUG_ON(!list_empty(&entry->node));
334 
335 		strlist__delete(entry->tevlist);
336 		clear_perf_probe_event(&entry->pev);
337 		zfree(&entry->spev);
338 		free(entry);
339 	}
340 }
341 
342 static struct probe_cache_entry *
343 probe_cache_entry__new(struct perf_probe_event *pev)
344 {
345 	struct probe_cache_entry *entry = zalloc(sizeof(*entry));
346 
347 	if (entry) {
348 		INIT_LIST_HEAD(&entry->node);
349 		entry->tevlist = strlist__new(NULL, NULL);
350 		if (!entry->tevlist)
351 			zfree(&entry);
352 		else if (pev) {
353 			entry->spev = synthesize_perf_probe_command(pev);
354 			if (!entry->spev ||
355 			    perf_probe_event__copy(&entry->pev, pev) < 0) {
356 				probe_cache_entry__delete(entry);
357 				return NULL;
358 			}
359 		}
360 	}
361 
362 	return entry;
363 }
364 
365 int probe_cache_entry__get_event(struct probe_cache_entry *entry,
366 				 struct probe_trace_event **tevs)
367 {
368 	struct probe_trace_event *tev;
369 	struct str_node *node;
370 	int ret, i;
371 
372 	ret = strlist__nr_entries(entry->tevlist);
373 	if (ret > probe_conf.max_probes)
374 		return -E2BIG;
375 
376 	*tevs = zalloc(ret * sizeof(*tev));
377 	if (!*tevs)
378 		return -ENOMEM;
379 
380 	i = 0;
381 	strlist__for_each_entry(node, entry->tevlist) {
382 		tev = &(*tevs)[i++];
383 		ret = parse_probe_trace_command(node->s, tev);
384 		if (ret < 0)
385 			break;
386 	}
387 	return i;
388 }
389 
390 /* For the kernel probe caches, pass target = NULL or DSO__NAME_KALLSYMS */
391 static int probe_cache__open(struct probe_cache *pcache, const char *target)
392 {
393 	char cpath[PATH_MAX];
394 	char sbuildid[SBUILD_ID_SIZE];
395 	char *dir_name = NULL;
396 	bool is_kallsyms = false;
397 	int ret, fd;
398 
399 	if (target && build_id_cache__cached(target)) {
400 		/* This is a cached buildid */
401 		strncpy(sbuildid, target, SBUILD_ID_SIZE);
402 		dir_name = build_id_cache__linkname(sbuildid, NULL, 0);
403 		goto found;
404 	}
405 
406 	if (!target || !strcmp(target, DSO__NAME_KALLSYMS)) {
407 		target = DSO__NAME_KALLSYMS;
408 		is_kallsyms = true;
409 		ret = sysfs__sprintf_build_id("/", sbuildid);
410 	} else
411 		ret = filename__sprintf_build_id(target, sbuildid);
412 
413 	if (ret < 0) {
414 		pr_debug("Failed to get build-id from %s.\n", target);
415 		return ret;
416 	}
417 
418 	/* If we have no buildid cache, make it */
419 	if (!build_id_cache__cached(sbuildid)) {
420 		ret = build_id_cache__add_s(sbuildid, target,
421 					    is_kallsyms, NULL);
422 		if (ret < 0) {
423 			pr_debug("Failed to add build-id cache: %s\n", target);
424 			return ret;
425 		}
426 	}
427 
428 	dir_name = build_id_cache__cachedir(sbuildid, target, is_kallsyms,
429 					    false);
430 found:
431 	if (!dir_name) {
432 		pr_debug("Failed to get cache from %s\n", target);
433 		return -ENOMEM;
434 	}
435 
436 	snprintf(cpath, PATH_MAX, "%s/probes", dir_name);
437 	fd = open(cpath, O_CREAT | O_RDWR, 0644);
438 	if (fd < 0)
439 		pr_debug("Failed to open cache(%d): %s\n", fd, cpath);
440 	free(dir_name);
441 	pcache->fd = fd;
442 
443 	return fd;
444 }
445 
446 static int probe_cache__load(struct probe_cache *pcache)
447 {
448 	struct probe_cache_entry *entry = NULL;
449 	char buf[MAX_CMDLEN], *p;
450 	int ret = 0;
451 	FILE *fp;
452 
453 	fp = fdopen(dup(pcache->fd), "r");
454 	if (!fp)
455 		return -EINVAL;
456 
457 	while (!feof(fp)) {
458 		if (!fgets(buf, MAX_CMDLEN, fp))
459 			break;
460 		p = strchr(buf, '\n');
461 		if (p)
462 			*p = '\0';
463 		/* #perf_probe_event or %sdt_event */
464 		if (buf[0] == '#' || buf[0] == '%') {
465 			entry = probe_cache_entry__new(NULL);
466 			if (!entry) {
467 				ret = -ENOMEM;
468 				goto out;
469 			}
470 			if (buf[0] == '%')
471 				entry->sdt = true;
472 			entry->spev = strdup(buf + 1);
473 			if (entry->spev)
474 				ret = parse_perf_probe_command(buf + 1,
475 								&entry->pev);
476 			else
477 				ret = -ENOMEM;
478 			if (ret < 0) {
479 				probe_cache_entry__delete(entry);
480 				goto out;
481 			}
482 			list_add_tail(&entry->node, &pcache->entries);
483 		} else {	/* trace_probe_event */
484 			if (!entry) {
485 				ret = -EINVAL;
486 				goto out;
487 			}
488 			strlist__add(entry->tevlist, buf);
489 		}
490 	}
491 out:
492 	fclose(fp);
493 	return ret;
494 }
495 
496 static struct probe_cache *probe_cache__alloc(void)
497 {
498 	struct probe_cache *pcache = zalloc(sizeof(*pcache));
499 
500 	if (pcache) {
501 		INIT_LIST_HEAD(&pcache->entries);
502 		pcache->fd = -EINVAL;
503 	}
504 	return pcache;
505 }
506 
507 void probe_cache__purge(struct probe_cache *pcache)
508 {
509 	struct probe_cache_entry *entry, *n;
510 
511 	list_for_each_entry_safe(entry, n, &pcache->entries, node) {
512 		list_del_init(&entry->node);
513 		probe_cache_entry__delete(entry);
514 	}
515 }
516 
517 void probe_cache__delete(struct probe_cache *pcache)
518 {
519 	if (!pcache)
520 		return;
521 
522 	probe_cache__purge(pcache);
523 	if (pcache->fd > 0)
524 		close(pcache->fd);
525 	free(pcache);
526 }
527 
528 struct probe_cache *probe_cache__new(const char *target)
529 {
530 	struct probe_cache *pcache = probe_cache__alloc();
531 	int ret;
532 
533 	if (!pcache)
534 		return NULL;
535 
536 	ret = probe_cache__open(pcache, target);
537 	if (ret < 0) {
538 		pr_debug("Cache open error: %d\n", ret);
539 		goto out_err;
540 	}
541 
542 	ret = probe_cache__load(pcache);
543 	if (ret < 0) {
544 		pr_debug("Cache read error: %d\n", ret);
545 		goto out_err;
546 	}
547 
548 	return pcache;
549 
550 out_err:
551 	probe_cache__delete(pcache);
552 	return NULL;
553 }
554 
555 static bool streql(const char *a, const char *b)
556 {
557 	if (a == b)
558 		return true;
559 
560 	if (!a || !b)
561 		return false;
562 
563 	return !strcmp(a, b);
564 }
565 
566 struct probe_cache_entry *
567 probe_cache__find(struct probe_cache *pcache, struct perf_probe_event *pev)
568 {
569 	struct probe_cache_entry *entry = NULL;
570 	char *cmd = synthesize_perf_probe_command(pev);
571 
572 	if (!cmd)
573 		return NULL;
574 
575 	for_each_probe_cache_entry(entry, pcache) {
576 		if (pev->sdt) {
577 			if (entry->pev.event &&
578 			    streql(entry->pev.event, pev->event) &&
579 			    (!pev->group ||
580 			     streql(entry->pev.group, pev->group)))
581 				goto found;
582 
583 			continue;
584 		}
585 		/* Hit if same event name or same command-string */
586 		if ((pev->event &&
587 		     (streql(entry->pev.group, pev->group) &&
588 		      streql(entry->pev.event, pev->event))) ||
589 		    (!strcmp(entry->spev, cmd)))
590 			goto found;
591 	}
592 	entry = NULL;
593 
594 found:
595 	free(cmd);
596 	return entry;
597 }
598 
599 struct probe_cache_entry *
600 probe_cache__find_by_name(struct probe_cache *pcache,
601 			  const char *group, const char *event)
602 {
603 	struct probe_cache_entry *entry = NULL;
604 
605 	for_each_probe_cache_entry(entry, pcache) {
606 		/* Hit if same event name or same command-string */
607 		if (streql(entry->pev.group, group) &&
608 		    streql(entry->pev.event, event))
609 			goto found;
610 	}
611 	entry = NULL;
612 
613 found:
614 	return entry;
615 }
616 
617 int probe_cache__add_entry(struct probe_cache *pcache,
618 			   struct perf_probe_event *pev,
619 			   struct probe_trace_event *tevs, int ntevs)
620 {
621 	struct probe_cache_entry *entry = NULL;
622 	char *command;
623 	int i, ret = 0;
624 
625 	if (!pcache || !pev || !tevs || ntevs <= 0) {
626 		ret = -EINVAL;
627 		goto out_err;
628 	}
629 
630 	/* Remove old cache entry */
631 	entry = probe_cache__find(pcache, pev);
632 	if (entry) {
633 		list_del_init(&entry->node);
634 		probe_cache_entry__delete(entry);
635 	}
636 
637 	ret = -ENOMEM;
638 	entry = probe_cache_entry__new(pev);
639 	if (!entry)
640 		goto out_err;
641 
642 	for (i = 0; i < ntevs; i++) {
643 		if (!tevs[i].point.symbol)
644 			continue;
645 
646 		command = synthesize_probe_trace_command(&tevs[i]);
647 		if (!command)
648 			goto out_err;
649 		strlist__add(entry->tevlist, command);
650 		free(command);
651 	}
652 	list_add_tail(&entry->node, &pcache->entries);
653 	pr_debug("Added probe cache: %d\n", ntevs);
654 	return 0;
655 
656 out_err:
657 	pr_debug("Failed to add probe caches\n");
658 	probe_cache_entry__delete(entry);
659 	return ret;
660 }
661 
662 #ifdef HAVE_GELF_GETNOTE_SUPPORT
663 static unsigned long long sdt_note__get_addr(struct sdt_note *note)
664 {
665 	return note->bit32 ? (unsigned long long)note->addr.a32[0]
666 		 : (unsigned long long)note->addr.a64[0];
667 }
668 
669 int probe_cache__scan_sdt(struct probe_cache *pcache, const char *pathname)
670 {
671 	struct probe_cache_entry *entry = NULL;
672 	struct list_head sdtlist;
673 	struct sdt_note *note;
674 	char *buf;
675 	char sdtgrp[64];
676 	int ret;
677 
678 	INIT_LIST_HEAD(&sdtlist);
679 	ret = get_sdt_note_list(&sdtlist, pathname);
680 	if (ret < 0) {
681 		pr_debug("Failed to get sdt note: %d\n", ret);
682 		return ret;
683 	}
684 	list_for_each_entry(note, &sdtlist, note_list) {
685 		ret = snprintf(sdtgrp, 64, "sdt_%s", note->provider);
686 		if (ret < 0)
687 			break;
688 		/* Try to find same-name entry */
689 		entry = probe_cache__find_by_name(pcache, sdtgrp, note->name);
690 		if (!entry) {
691 			entry = probe_cache_entry__new(NULL);
692 			if (!entry) {
693 				ret = -ENOMEM;
694 				break;
695 			}
696 			entry->sdt = true;
697 			ret = asprintf(&entry->spev, "%s:%s=%s", sdtgrp,
698 					note->name, note->name);
699 			if (ret < 0)
700 				break;
701 			entry->pev.event = strdup(note->name);
702 			entry->pev.group = strdup(sdtgrp);
703 			list_add_tail(&entry->node, &pcache->entries);
704 		}
705 		ret = asprintf(&buf, "p:%s/%s %s:0x%llx",
706 				sdtgrp, note->name, pathname,
707 				sdt_note__get_addr(note));
708 		if (ret < 0)
709 			break;
710 		strlist__add(entry->tevlist, buf);
711 		free(buf);
712 		entry = NULL;
713 	}
714 	if (entry) {
715 		list_del_init(&entry->node);
716 		probe_cache_entry__delete(entry);
717 	}
718 	cleanup_sdt_note_list(&sdtlist);
719 	return ret;
720 }
721 #endif
722 
723 static int probe_cache_entry__write(struct probe_cache_entry *entry, int fd)
724 {
725 	struct str_node *snode;
726 	struct stat st;
727 	struct iovec iov[3];
728 	const char *prefix = entry->sdt ? "%" : "#";
729 	int ret;
730 	/* Save stat for rollback */
731 	ret = fstat(fd, &st);
732 	if (ret < 0)
733 		return ret;
734 
735 	pr_debug("Writing cache: %s%s\n", prefix, entry->spev);
736 	iov[0].iov_base = (void *)prefix; iov[0].iov_len = 1;
737 	iov[1].iov_base = entry->spev; iov[1].iov_len = strlen(entry->spev);
738 	iov[2].iov_base = (void *)"\n"; iov[2].iov_len = 1;
739 	ret = writev(fd, iov, 3);
740 	if (ret < (int)iov[1].iov_len + 2)
741 		goto rollback;
742 
743 	strlist__for_each_entry(snode, entry->tevlist) {
744 		iov[0].iov_base = (void *)snode->s;
745 		iov[0].iov_len = strlen(snode->s);
746 		iov[1].iov_base = (void *)"\n"; iov[1].iov_len = 1;
747 		ret = writev(fd, iov, 2);
748 		if (ret < (int)iov[0].iov_len + 1)
749 			goto rollback;
750 	}
751 	return 0;
752 
753 rollback:
754 	/* Rollback to avoid cache file corruption */
755 	if (ret > 0)
756 		ret = -1;
757 	if (ftruncate(fd, st.st_size) < 0)
758 		ret = -2;
759 
760 	return ret;
761 }
762 
763 int probe_cache__commit(struct probe_cache *pcache)
764 {
765 	struct probe_cache_entry *entry;
766 	int ret = 0;
767 
768 	/* TBD: if we do not update existing entries, skip it */
769 	ret = lseek(pcache->fd, 0, SEEK_SET);
770 	if (ret < 0)
771 		goto out;
772 
773 	ret = ftruncate(pcache->fd, 0);
774 	if (ret < 0)
775 		goto out;
776 
777 	for_each_probe_cache_entry(entry, pcache) {
778 		ret = probe_cache_entry__write(entry, pcache->fd);
779 		pr_debug("Cache committed: %d\n", ret);
780 		if (ret < 0)
781 			break;
782 	}
783 out:
784 	return ret;
785 }
786 
787 static bool probe_cache_entry__compare(struct probe_cache_entry *entry,
788 				       struct strfilter *filter)
789 {
790 	char buf[128], *ptr = entry->spev;
791 
792 	if (entry->pev.event) {
793 		snprintf(buf, 128, "%s:%s", entry->pev.group, entry->pev.event);
794 		ptr = buf;
795 	}
796 	return strfilter__compare(filter, ptr);
797 }
798 
799 int probe_cache__filter_purge(struct probe_cache *pcache,
800 			      struct strfilter *filter)
801 {
802 	struct probe_cache_entry *entry, *tmp;
803 
804 	list_for_each_entry_safe(entry, tmp, &pcache->entries, node) {
805 		if (probe_cache_entry__compare(entry, filter)) {
806 			pr_info("Removed cached event: %s\n", entry->spev);
807 			list_del_init(&entry->node);
808 			probe_cache_entry__delete(entry);
809 		}
810 	}
811 	return 0;
812 }
813 
814 static int probe_cache__show_entries(struct probe_cache *pcache,
815 				     struct strfilter *filter)
816 {
817 	struct probe_cache_entry *entry;
818 
819 	for_each_probe_cache_entry(entry, pcache) {
820 		if (probe_cache_entry__compare(entry, filter))
821 			printf("%s\n", entry->spev);
822 	}
823 	return 0;
824 }
825 
826 /* Show all cached probes */
827 int probe_cache__show_all_caches(struct strfilter *filter)
828 {
829 	struct probe_cache *pcache;
830 	struct strlist *bidlist;
831 	struct str_node *nd;
832 	char *buf = strfilter__string(filter);
833 
834 	pr_debug("list cache with filter: %s\n", buf);
835 	free(buf);
836 
837 	bidlist = build_id_cache__list_all(true);
838 	if (!bidlist) {
839 		pr_debug("Failed to get buildids: %d\n", errno);
840 		return -EINVAL;
841 	}
842 	strlist__for_each_entry(nd, bidlist) {
843 		pcache = probe_cache__new(nd->s);
844 		if (!pcache)
845 			continue;
846 		if (!list_empty(&pcache->entries)) {
847 			buf = build_id_cache__origname(nd->s);
848 			printf("%s (%s):\n", buf, nd->s);
849 			free(buf);
850 			probe_cache__show_entries(pcache, filter);
851 		}
852 		probe_cache__delete(pcache);
853 	}
854 	strlist__delete(bidlist);
855 
856 	return 0;
857 }
858