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