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1// SPDX-License-Identifier: GPL-2.0
2#include <errno.h>
3#include <stdlib.h>
4#include <bpf/bpf.h>
5#include <bpf/btf.h>
6#include <bpf/libbpf.h>
7#include <linux/btf.h>
8#include <linux/err.h>
9#include <linux/string.h>
10#include <internal/lib.h>
11#include <symbol/kallsyms.h>
12#include "bpf-event.h"
13#include "bpf-utils.h"
14#include "debug.h"
15#include "dso.h"
16#include "symbol.h"
17#include "machine.h"
18#include "env.h"
19#include "session.h"
20#include "map.h"
21#include "evlist.h"
22#include "record.h"
23#include "util/synthetic-events.h"
24
25#ifndef HAVE_LIBBPF_BTF__LOAD_FROM_KERNEL_BY_ID
26struct btf *btf__load_from_kernel_by_id(__u32 id)
27{
28 struct btf *btf;
29#pragma GCC diagnostic push
30#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
31 int err = btf__get_from_id(id, &btf);
32#pragma GCC diagnostic pop
33
34 return err ? ERR_PTR(err) : btf;
35}
36#endif
37
38#ifndef HAVE_LIBBPF_BPF_PROG_LOAD
39LIBBPF_API int bpf_load_program(enum bpf_prog_type type,
40 const struct bpf_insn *insns, size_t insns_cnt,
41 const char *license, __u32 kern_version,
42 char *log_buf, size_t log_buf_sz);
43
44int bpf_prog_load(enum bpf_prog_type prog_type,
45 const char *prog_name __maybe_unused,
46 const char *license,
47 const struct bpf_insn *insns, size_t insn_cnt,
48 const struct bpf_prog_load_opts *opts)
49{
50#pragma GCC diagnostic push
51#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
52 return bpf_load_program(prog_type, insns, insn_cnt, license,
53 opts->kern_version, opts->log_buf, opts->log_size);
54#pragma GCC diagnostic pop
55}
56#endif
57
58#ifndef HAVE_LIBBPF_BPF_OBJECT__NEXT_PROGRAM
59struct bpf_program *
60bpf_object__next_program(const struct bpf_object *obj, struct bpf_program *prev)
61{
62#pragma GCC diagnostic push
63#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
64 return bpf_program__next(prev, obj);
65#pragma GCC diagnostic pop
66}
67#endif
68
69#ifndef HAVE_LIBBPF_BPF_OBJECT__NEXT_MAP
70struct bpf_map *
71bpf_object__next_map(const struct bpf_object *obj, const struct bpf_map *prev)
72{
73#pragma GCC diagnostic push
74#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
75 return bpf_map__next(prev, obj);
76#pragma GCC diagnostic pop
77}
78#endif
79
80#ifndef HAVE_LIBBPF_BTF__RAW_DATA
81const void *
82btf__raw_data(const struct btf *btf_ro, __u32 *size)
83{
84#pragma GCC diagnostic push
85#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
86 return btf__get_raw_data(btf_ro, size);
87#pragma GCC diagnostic pop
88}
89#endif
90
91static int snprintf_hex(char *buf, size_t size, unsigned char *data, size_t len)
92{
93 int ret = 0;
94 size_t i;
95
96 for (i = 0; i < len; i++)
97 ret += snprintf(buf + ret, size - ret, "%02x", data[i]);
98 return ret;
99}
100
101static int machine__process_bpf_event_load(struct machine *machine,
102 union perf_event *event,
103 struct perf_sample *sample __maybe_unused)
104{
105 struct bpf_prog_info_node *info_node;
106 struct perf_env *env = machine->env;
107 struct perf_bpil *info_linear;
108 int id = event->bpf.id;
109 unsigned int i;
110
111 /* perf-record, no need to handle bpf-event */
112 if (env == NULL)
113 return 0;
114
115 info_node = perf_env__find_bpf_prog_info(env, id);
116 if (!info_node)
117 return 0;
118 info_linear = info_node->info_linear;
119
120 for (i = 0; i < info_linear->info.nr_jited_ksyms; i++) {
121 u64 *addrs = (u64 *)(uintptr_t)(info_linear->info.jited_ksyms);
122 u64 addr = addrs[i];
123 struct map *map = maps__find(machine__kernel_maps(machine), addr);
124
125 if (map) {
126 map->dso->binary_type = DSO_BINARY_TYPE__BPF_PROG_INFO;
127 map->dso->bpf_prog.id = id;
128 map->dso->bpf_prog.sub_id = i;
129 map->dso->bpf_prog.env = env;
130 }
131 }
132 return 0;
133}
134
135int machine__process_bpf(struct machine *machine, union perf_event *event,
136 struct perf_sample *sample)
137{
138 if (dump_trace)
139 perf_event__fprintf_bpf(event, stdout);
140
141 switch (event->bpf.type) {
142 case PERF_BPF_EVENT_PROG_LOAD:
143 return machine__process_bpf_event_load(machine, event, sample);
144
145 case PERF_BPF_EVENT_PROG_UNLOAD:
146 /*
147 * Do not free bpf_prog_info and btf of the program here,
148 * as annotation still need them. They will be freed at
149 * the end of the session.
150 */
151 break;
152 default:
153 pr_debug("unexpected bpf event type of %d\n", event->bpf.type);
154 break;
155 }
156 return 0;
157}
158
159static int perf_env__fetch_btf(struct perf_env *env,
160 u32 btf_id,
161 struct btf *btf)
162{
163 struct btf_node *node;
164 u32 data_size;
165 const void *data;
166
167 data = btf__raw_data(btf, &data_size);
168
169 node = malloc(data_size + sizeof(struct btf_node));
170 if (!node)
171 return -1;
172
173 node->id = btf_id;
174 node->data_size = data_size;
175 memcpy(node->data, data, data_size);
176
177 if (!perf_env__insert_btf(env, node)) {
178 /* Insertion failed because of a duplicate. */
179 free(node);
180 return -1;
181 }
182 return 0;
183}
184
185static int synthesize_bpf_prog_name(char *buf, int size,
186 struct bpf_prog_info *info,
187 struct btf *btf,
188 u32 sub_id)
189{
190 u8 (*prog_tags)[BPF_TAG_SIZE] = (void *)(uintptr_t)(info->prog_tags);
191 void *func_infos = (void *)(uintptr_t)(info->func_info);
192 u32 sub_prog_cnt = info->nr_jited_ksyms;
193 const struct bpf_func_info *finfo;
194 const char *short_name = NULL;
195 const struct btf_type *t;
196 int name_len;
197
198 name_len = snprintf(buf, size, "bpf_prog_");
199 name_len += snprintf_hex(buf + name_len, size - name_len,
200 prog_tags[sub_id], BPF_TAG_SIZE);
201 if (btf) {
202 finfo = func_infos + sub_id * info->func_info_rec_size;
203 t = btf__type_by_id(btf, finfo->type_id);
204 short_name = btf__name_by_offset(btf, t->name_off);
205 } else if (sub_id == 0 && sub_prog_cnt == 1) {
206 /* no subprog */
207 if (info->name[0])
208 short_name = info->name;
209 } else
210 short_name = "F";
211 if (short_name)
212 name_len += snprintf(buf + name_len, size - name_len,
213 "_%s", short_name);
214 return name_len;
215}
216
217/*
218 * Synthesize PERF_RECORD_KSYMBOL and PERF_RECORD_BPF_EVENT for one bpf
219 * program. One PERF_RECORD_BPF_EVENT is generated for the program. And
220 * one PERF_RECORD_KSYMBOL is generated for each sub program.
221 *
222 * Returns:
223 * 0 for success;
224 * -1 for failures;
225 * -2 for lack of kernel support.
226 */
227static int perf_event__synthesize_one_bpf_prog(struct perf_session *session,
228 perf_event__handler_t process,
229 struct machine *machine,
230 int fd,
231 union perf_event *event,
232 struct record_opts *opts)
233{
234 struct perf_record_ksymbol *ksymbol_event = &event->ksymbol;
235 struct perf_record_bpf_event *bpf_event = &event->bpf;
236 struct perf_tool *tool = session->tool;
237 struct bpf_prog_info_node *info_node;
238 struct perf_bpil *info_linear;
239 struct bpf_prog_info *info;
240 struct btf *btf = NULL;
241 struct perf_env *env;
242 u32 sub_prog_cnt, i;
243 int err = 0;
244 u64 arrays;
245
246 /*
247 * for perf-record and perf-report use header.env;
248 * otherwise, use global perf_env.
249 */
250 env = session->data ? &session->header.env : &perf_env;
251
252 arrays = 1UL << PERF_BPIL_JITED_KSYMS;
253 arrays |= 1UL << PERF_BPIL_JITED_FUNC_LENS;
254 arrays |= 1UL << PERF_BPIL_FUNC_INFO;
255 arrays |= 1UL << PERF_BPIL_PROG_TAGS;
256 arrays |= 1UL << PERF_BPIL_JITED_INSNS;
257 arrays |= 1UL << PERF_BPIL_LINE_INFO;
258 arrays |= 1UL << PERF_BPIL_JITED_LINE_INFO;
259
260 info_linear = get_bpf_prog_info_linear(fd, arrays);
261 if (IS_ERR_OR_NULL(info_linear)) {
262 info_linear = NULL;
263 pr_debug("%s: failed to get BPF program info. aborting\n", __func__);
264 return -1;
265 }
266
267 if (info_linear->info_len < offsetof(struct bpf_prog_info, prog_tags)) {
268 free(info_linear);
269 pr_debug("%s: the kernel is too old, aborting\n", __func__);
270 return -2;
271 }
272
273 info = &info_linear->info;
274 if (!info->jited_ksyms) {
275 free(info_linear);
276 return -1;
277 }
278
279 /* number of ksyms, func_lengths, and tags should match */
280 sub_prog_cnt = info->nr_jited_ksyms;
281 if (sub_prog_cnt != info->nr_prog_tags ||
282 sub_prog_cnt != info->nr_jited_func_lens) {
283 free(info_linear);
284 return -1;
285 }
286
287 /* check BTF func info support */
288 if (info->btf_id && info->nr_func_info && info->func_info_rec_size) {
289 /* btf func info number should be same as sub_prog_cnt */
290 if (sub_prog_cnt != info->nr_func_info) {
291 pr_debug("%s: mismatch in BPF sub program count and BTF function info count, aborting\n", __func__);
292 free(info_linear);
293 return -1;
294 }
295 btf = btf__load_from_kernel_by_id(info->btf_id);
296 if (libbpf_get_error(btf)) {
297 pr_debug("%s: failed to get BTF of id %u, aborting\n", __func__, info->btf_id);
298 err = -1;
299 goto out;
300 }
301 perf_env__fetch_btf(env, info->btf_id, btf);
302 }
303
304 /* Synthesize PERF_RECORD_KSYMBOL */
305 for (i = 0; i < sub_prog_cnt; i++) {
306 __u32 *prog_lens = (__u32 *)(uintptr_t)(info->jited_func_lens);
307 __u64 *prog_addrs = (__u64 *)(uintptr_t)(info->jited_ksyms);
308 int name_len;
309
310 *ksymbol_event = (struct perf_record_ksymbol) {
311 .header = {
312 .type = PERF_RECORD_KSYMBOL,
313 .size = offsetof(struct perf_record_ksymbol, name),
314 },
315 .addr = prog_addrs[i],
316 .len = prog_lens[i],
317 .ksym_type = PERF_RECORD_KSYMBOL_TYPE_BPF,
318 .flags = 0,
319 };
320
321 name_len = synthesize_bpf_prog_name(ksymbol_event->name,
322 KSYM_NAME_LEN, info, btf, i);
323 ksymbol_event->header.size += PERF_ALIGN(name_len + 1,
324 sizeof(u64));
325
326 memset((void *)event + event->header.size, 0, machine->id_hdr_size);
327 event->header.size += machine->id_hdr_size;
328 err = perf_tool__process_synth_event(tool, event,
329 machine, process);
330 }
331
332 if (!opts->no_bpf_event) {
333 /* Synthesize PERF_RECORD_BPF_EVENT */
334 *bpf_event = (struct perf_record_bpf_event) {
335 .header = {
336 .type = PERF_RECORD_BPF_EVENT,
337 .size = sizeof(struct perf_record_bpf_event),
338 },
339 .type = PERF_BPF_EVENT_PROG_LOAD,
340 .flags = 0,
341 .id = info->id,
342 };
343 memcpy(bpf_event->tag, info->tag, BPF_TAG_SIZE);
344 memset((void *)event + event->header.size, 0, machine->id_hdr_size);
345 event->header.size += machine->id_hdr_size;
346
347 /* save bpf_prog_info to env */
348 info_node = malloc(sizeof(struct bpf_prog_info_node));
349 if (!info_node) {
350 err = -1;
351 goto out;
352 }
353
354 info_node->info_linear = info_linear;
355 perf_env__insert_bpf_prog_info(env, info_node);
356 info_linear = NULL;
357
358 /*
359 * process after saving bpf_prog_info to env, so that
360 * required information is ready for look up
361 */
362 err = perf_tool__process_synth_event(tool, event,
363 machine, process);
364 }
365
366out:
367 free(info_linear);
368 btf__free(btf);
369 return err ? -1 : 0;
370}
371
372struct kallsyms_parse {
373 union perf_event *event;
374 perf_event__handler_t process;
375 struct machine *machine;
376 struct perf_tool *tool;
377};
378
379static int
380process_bpf_image(char *name, u64 addr, struct kallsyms_parse *data)
381{
382 struct machine *machine = data->machine;
383 union perf_event *event = data->event;
384 struct perf_record_ksymbol *ksymbol;
385 int len;
386
387 ksymbol = &event->ksymbol;
388
389 *ksymbol = (struct perf_record_ksymbol) {
390 .header = {
391 .type = PERF_RECORD_KSYMBOL,
392 .size = offsetof(struct perf_record_ksymbol, name),
393 },
394 .addr = addr,
395 .len = page_size,
396 .ksym_type = PERF_RECORD_KSYMBOL_TYPE_BPF,
397 .flags = 0,
398 };
399
400 len = scnprintf(ksymbol->name, KSYM_NAME_LEN, "%s", name);
401 ksymbol->header.size += PERF_ALIGN(len + 1, sizeof(u64));
402 memset((void *) event + event->header.size, 0, machine->id_hdr_size);
403 event->header.size += machine->id_hdr_size;
404
405 return perf_tool__process_synth_event(data->tool, event, machine,
406 data->process);
407}
408
409static int
410kallsyms_process_symbol(void *data, const char *_name,
411 char type __maybe_unused, u64 start)
412{
413 char disp[KSYM_NAME_LEN];
414 char *module, *name;
415 unsigned long id;
416 int err = 0;
417
418 module = strchr(_name, '\t');
419 if (!module)
420 return 0;
421
422 /* We are going after [bpf] module ... */
423 if (strcmp(module + 1, "[bpf]"))
424 return 0;
425
426 name = memdup(_name, (module - _name) + 1);
427 if (!name)
428 return -ENOMEM;
429
430 name[module - _name] = 0;
431
432 /* .. and only for trampolines and dispatchers */
433 if ((sscanf(name, "bpf_trampoline_%lu", &id) == 1) ||
434 (sscanf(name, "bpf_dispatcher_%s", disp) == 1))
435 err = process_bpf_image(name, start, data);
436
437 free(name);
438 return err;
439}
440
441int perf_event__synthesize_bpf_events(struct perf_session *session,
442 perf_event__handler_t process,
443 struct machine *machine,
444 struct record_opts *opts)
445{
446 const char *kallsyms_filename = "/proc/kallsyms";
447 struct kallsyms_parse arg;
448 union perf_event *event;
449 __u32 id = 0;
450 int err;
451 int fd;
452
453 event = malloc(sizeof(event->bpf) + KSYM_NAME_LEN + machine->id_hdr_size);
454 if (!event)
455 return -1;
456
457 /* Synthesize all the bpf programs in system. */
458 while (true) {
459 err = bpf_prog_get_next_id(id, &id);
460 if (err) {
461 if (errno == ENOENT) {
462 err = 0;
463 break;
464 }
465 pr_debug("%s: can't get next program: %s%s\n",
466 __func__, strerror(errno),
467 errno == EINVAL ? " -- kernel too old?" : "");
468 /* don't report error on old kernel or EPERM */
469 err = (errno == EINVAL || errno == EPERM) ? 0 : -1;
470 break;
471 }
472 fd = bpf_prog_get_fd_by_id(id);
473 if (fd < 0) {
474 pr_debug("%s: failed to get fd for prog_id %u\n",
475 __func__, id);
476 continue;
477 }
478
479 err = perf_event__synthesize_one_bpf_prog(session, process,
480 machine, fd,
481 event, opts);
482 close(fd);
483 if (err) {
484 /* do not return error for old kernel */
485 if (err == -2)
486 err = 0;
487 break;
488 }
489 }
490
491 /* Synthesize all the bpf images - trampolines/dispatchers. */
492 if (symbol_conf.kallsyms_name != NULL)
493 kallsyms_filename = symbol_conf.kallsyms_name;
494
495 arg = (struct kallsyms_parse) {
496 .event = event,
497 .process = process,
498 .machine = machine,
499 .tool = session->tool,
500 };
501
502 if (kallsyms__parse(kallsyms_filename, &arg, kallsyms_process_symbol)) {
503 pr_err("%s: failed to synthesize bpf images: %s\n",
504 __func__, strerror(errno));
505 }
506
507 free(event);
508 return err;
509}
510
511static void perf_env__add_bpf_info(struct perf_env *env, u32 id)
512{
513 struct bpf_prog_info_node *info_node;
514 struct perf_bpil *info_linear;
515 struct btf *btf = NULL;
516 u64 arrays;
517 u32 btf_id;
518 int fd;
519
520 fd = bpf_prog_get_fd_by_id(id);
521 if (fd < 0)
522 return;
523
524 arrays = 1UL << PERF_BPIL_JITED_KSYMS;
525 arrays |= 1UL << PERF_BPIL_JITED_FUNC_LENS;
526 arrays |= 1UL << PERF_BPIL_FUNC_INFO;
527 arrays |= 1UL << PERF_BPIL_PROG_TAGS;
528 arrays |= 1UL << PERF_BPIL_JITED_INSNS;
529 arrays |= 1UL << PERF_BPIL_LINE_INFO;
530 arrays |= 1UL << PERF_BPIL_JITED_LINE_INFO;
531
532 info_linear = get_bpf_prog_info_linear(fd, arrays);
533 if (IS_ERR_OR_NULL(info_linear)) {
534 pr_debug("%s: failed to get BPF program info. aborting\n", __func__);
535 goto out;
536 }
537
538 btf_id = info_linear->info.btf_id;
539
540 info_node = malloc(sizeof(struct bpf_prog_info_node));
541 if (info_node) {
542 info_node->info_linear = info_linear;
543 perf_env__insert_bpf_prog_info(env, info_node);
544 } else
545 free(info_linear);
546
547 if (btf_id == 0)
548 goto out;
549
550 btf = btf__load_from_kernel_by_id(btf_id);
551 if (libbpf_get_error(btf)) {
552 pr_debug("%s: failed to get BTF of id %u, aborting\n",
553 __func__, btf_id);
554 goto out;
555 }
556 perf_env__fetch_btf(env, btf_id, btf);
557
558out:
559 btf__free(btf);
560 close(fd);
561}
562
563static int bpf_event__sb_cb(union perf_event *event, void *data)
564{
565 struct perf_env *env = data;
566
567 if (event->header.type != PERF_RECORD_BPF_EVENT)
568 return -1;
569
570 switch (event->bpf.type) {
571 case PERF_BPF_EVENT_PROG_LOAD:
572 perf_env__add_bpf_info(env, event->bpf.id);
573
574 case PERF_BPF_EVENT_PROG_UNLOAD:
575 /*
576 * Do not free bpf_prog_info and btf of the program here,
577 * as annotation still need them. They will be freed at
578 * the end of the session.
579 */
580 break;
581 default:
582 pr_debug("unexpected bpf event type of %d\n", event->bpf.type);
583 break;
584 }
585
586 return 0;
587}
588
589int evlist__add_bpf_sb_event(struct evlist *evlist, struct perf_env *env)
590{
591 struct perf_event_attr attr = {
592 .type = PERF_TYPE_SOFTWARE,
593 .config = PERF_COUNT_SW_DUMMY,
594 .sample_id_all = 1,
595 .watermark = 1,
596 .bpf_event = 1,
597 .size = sizeof(attr), /* to capture ABI version */
598 };
599
600 /*
601 * Older gcc versions don't support designated initializers, like above,
602 * for unnamed union members, such as the following:
603 */
604 attr.wakeup_watermark = 1;
605
606 return evlist__add_sb_event(evlist, &attr, bpf_event__sb_cb, env);
607}
608
609void bpf_event__print_bpf_prog_info(struct bpf_prog_info *info,
610 struct perf_env *env,
611 FILE *fp)
612{
613 __u32 *prog_lens = (__u32 *)(uintptr_t)(info->jited_func_lens);
614 __u64 *prog_addrs = (__u64 *)(uintptr_t)(info->jited_ksyms);
615 char name[KSYM_NAME_LEN];
616 struct btf *btf = NULL;
617 u32 sub_prog_cnt, i;
618
619 sub_prog_cnt = info->nr_jited_ksyms;
620 if (sub_prog_cnt != info->nr_prog_tags ||
621 sub_prog_cnt != info->nr_jited_func_lens)
622 return;
623
624 if (info->btf_id) {
625 struct btf_node *node;
626
627 node = perf_env__find_btf(env, info->btf_id);
628 if (node)
629 btf = btf__new((__u8 *)(node->data),
630 node->data_size);
631 }
632
633 if (sub_prog_cnt == 1) {
634 synthesize_bpf_prog_name(name, KSYM_NAME_LEN, info, btf, 0);
635 fprintf(fp, "# bpf_prog_info %u: %s addr 0x%llx size %u\n",
636 info->id, name, prog_addrs[0], prog_lens[0]);
637 goto out;
638 }
639
640 fprintf(fp, "# bpf_prog_info %u:\n", info->id);
641 for (i = 0; i < sub_prog_cnt; i++) {
642 synthesize_bpf_prog_name(name, KSYM_NAME_LEN, info, btf, i);
643
644 fprintf(fp, "# \tsub_prog %u: %s addr 0x%llx size %u\n",
645 i, name, prog_addrs[i], prog_lens[i]);
646 }
647out:
648 btf__free(btf);
649}
1// SPDX-License-Identifier: GPL-2.0
2#include <errno.h>
3#include <stdlib.h>
4#include <bpf/bpf.h>
5#include <bpf/btf.h>
6#include <bpf/libbpf.h>
7#include <linux/btf.h>
8#include <linux/err.h>
9#include <linux/string.h>
10#include <internal/lib.h>
11#include <symbol/kallsyms.h>
12#include "bpf-event.h"
13#include "debug.h"
14#include "dso.h"
15#include "symbol.h"
16#include "machine.h"
17#include "env.h"
18#include "session.h"
19#include "map.h"
20#include "evlist.h"
21#include "record.h"
22#include "util/synthetic-events.h"
23
24#define ptr_to_u64(ptr) ((__u64)(unsigned long)(ptr))
25
26static int snprintf_hex(char *buf, size_t size, unsigned char *data, size_t len)
27{
28 int ret = 0;
29 size_t i;
30
31 for (i = 0; i < len; i++)
32 ret += snprintf(buf + ret, size - ret, "%02x", data[i]);
33 return ret;
34}
35
36static int machine__process_bpf_event_load(struct machine *machine,
37 union perf_event *event,
38 struct perf_sample *sample __maybe_unused)
39{
40 struct bpf_prog_info_linear *info_linear;
41 struct bpf_prog_info_node *info_node;
42 struct perf_env *env = machine->env;
43 int id = event->bpf.id;
44 unsigned int i;
45
46 /* perf-record, no need to handle bpf-event */
47 if (env == NULL)
48 return 0;
49
50 info_node = perf_env__find_bpf_prog_info(env, id);
51 if (!info_node)
52 return 0;
53 info_linear = info_node->info_linear;
54
55 for (i = 0; i < info_linear->info.nr_jited_ksyms; i++) {
56 u64 *addrs = (u64 *)(uintptr_t)(info_linear->info.jited_ksyms);
57 u64 addr = addrs[i];
58 struct map *map = maps__find(&machine->kmaps, addr);
59
60 if (map) {
61 map->dso->binary_type = DSO_BINARY_TYPE__BPF_PROG_INFO;
62 map->dso->bpf_prog.id = id;
63 map->dso->bpf_prog.sub_id = i;
64 map->dso->bpf_prog.env = env;
65 }
66 }
67 return 0;
68}
69
70int machine__process_bpf(struct machine *machine, union perf_event *event,
71 struct perf_sample *sample)
72{
73 if (dump_trace)
74 perf_event__fprintf_bpf(event, stdout);
75
76 switch (event->bpf.type) {
77 case PERF_BPF_EVENT_PROG_LOAD:
78 return machine__process_bpf_event_load(machine, event, sample);
79
80 case PERF_BPF_EVENT_PROG_UNLOAD:
81 /*
82 * Do not free bpf_prog_info and btf of the program here,
83 * as annotation still need them. They will be freed at
84 * the end of the session.
85 */
86 break;
87 default:
88 pr_debug("unexpected bpf event type of %d\n", event->bpf.type);
89 break;
90 }
91 return 0;
92}
93
94static int perf_env__fetch_btf(struct perf_env *env,
95 u32 btf_id,
96 struct btf *btf)
97{
98 struct btf_node *node;
99 u32 data_size;
100 const void *data;
101
102 data = btf__get_raw_data(btf, &data_size);
103
104 node = malloc(data_size + sizeof(struct btf_node));
105 if (!node)
106 return -1;
107
108 node->id = btf_id;
109 node->data_size = data_size;
110 memcpy(node->data, data, data_size);
111
112 perf_env__insert_btf(env, node);
113 return 0;
114}
115
116static int synthesize_bpf_prog_name(char *buf, int size,
117 struct bpf_prog_info *info,
118 struct btf *btf,
119 u32 sub_id)
120{
121 u8 (*prog_tags)[BPF_TAG_SIZE] = (void *)(uintptr_t)(info->prog_tags);
122 void *func_infos = (void *)(uintptr_t)(info->func_info);
123 u32 sub_prog_cnt = info->nr_jited_ksyms;
124 const struct bpf_func_info *finfo;
125 const char *short_name = NULL;
126 const struct btf_type *t;
127 int name_len;
128
129 name_len = snprintf(buf, size, "bpf_prog_");
130 name_len += snprintf_hex(buf + name_len, size - name_len,
131 prog_tags[sub_id], BPF_TAG_SIZE);
132 if (btf) {
133 finfo = func_infos + sub_id * info->func_info_rec_size;
134 t = btf__type_by_id(btf, finfo->type_id);
135 short_name = btf__name_by_offset(btf, t->name_off);
136 } else if (sub_id == 0 && sub_prog_cnt == 1) {
137 /* no subprog */
138 if (info->name[0])
139 short_name = info->name;
140 } else
141 short_name = "F";
142 if (short_name)
143 name_len += snprintf(buf + name_len, size - name_len,
144 "_%s", short_name);
145 return name_len;
146}
147
148/*
149 * Synthesize PERF_RECORD_KSYMBOL and PERF_RECORD_BPF_EVENT for one bpf
150 * program. One PERF_RECORD_BPF_EVENT is generated for the program. And
151 * one PERF_RECORD_KSYMBOL is generated for each sub program.
152 *
153 * Returns:
154 * 0 for success;
155 * -1 for failures;
156 * -2 for lack of kernel support.
157 */
158static int perf_event__synthesize_one_bpf_prog(struct perf_session *session,
159 perf_event__handler_t process,
160 struct machine *machine,
161 int fd,
162 union perf_event *event,
163 struct record_opts *opts)
164{
165 struct perf_record_ksymbol *ksymbol_event = &event->ksymbol;
166 struct perf_record_bpf_event *bpf_event = &event->bpf;
167 struct bpf_prog_info_linear *info_linear;
168 struct perf_tool *tool = session->tool;
169 struct bpf_prog_info_node *info_node;
170 struct bpf_prog_info *info;
171 struct btf *btf = NULL;
172 struct perf_env *env;
173 u32 sub_prog_cnt, i;
174 int err = 0;
175 u64 arrays;
176
177 /*
178 * for perf-record and perf-report use header.env;
179 * otherwise, use global perf_env.
180 */
181 env = session->data ? &session->header.env : &perf_env;
182
183 arrays = 1UL << BPF_PROG_INFO_JITED_KSYMS;
184 arrays |= 1UL << BPF_PROG_INFO_JITED_FUNC_LENS;
185 arrays |= 1UL << BPF_PROG_INFO_FUNC_INFO;
186 arrays |= 1UL << BPF_PROG_INFO_PROG_TAGS;
187 arrays |= 1UL << BPF_PROG_INFO_JITED_INSNS;
188 arrays |= 1UL << BPF_PROG_INFO_LINE_INFO;
189 arrays |= 1UL << BPF_PROG_INFO_JITED_LINE_INFO;
190
191 info_linear = bpf_program__get_prog_info_linear(fd, arrays);
192 if (IS_ERR_OR_NULL(info_linear)) {
193 info_linear = NULL;
194 pr_debug("%s: failed to get BPF program info. aborting\n", __func__);
195 return -1;
196 }
197
198 if (info_linear->info_len < offsetof(struct bpf_prog_info, prog_tags)) {
199 pr_debug("%s: the kernel is too old, aborting\n", __func__);
200 return -2;
201 }
202
203 info = &info_linear->info;
204
205 /* number of ksyms, func_lengths, and tags should match */
206 sub_prog_cnt = info->nr_jited_ksyms;
207 if (sub_prog_cnt != info->nr_prog_tags ||
208 sub_prog_cnt != info->nr_jited_func_lens)
209 return -1;
210
211 /* check BTF func info support */
212 if (info->btf_id && info->nr_func_info && info->func_info_rec_size) {
213 /* btf func info number should be same as sub_prog_cnt */
214 if (sub_prog_cnt != info->nr_func_info) {
215 pr_debug("%s: mismatch in BPF sub program count and BTF function info count, aborting\n", __func__);
216 err = -1;
217 goto out;
218 }
219 if (btf__get_from_id(info->btf_id, &btf)) {
220 pr_debug("%s: failed to get BTF of id %u, aborting\n", __func__, info->btf_id);
221 err = -1;
222 btf = NULL;
223 goto out;
224 }
225 perf_env__fetch_btf(env, info->btf_id, btf);
226 }
227
228 /* Synthesize PERF_RECORD_KSYMBOL */
229 for (i = 0; i < sub_prog_cnt; i++) {
230 __u32 *prog_lens = (__u32 *)(uintptr_t)(info->jited_func_lens);
231 __u64 *prog_addrs = (__u64 *)(uintptr_t)(info->jited_ksyms);
232 int name_len;
233
234 *ksymbol_event = (struct perf_record_ksymbol) {
235 .header = {
236 .type = PERF_RECORD_KSYMBOL,
237 .size = offsetof(struct perf_record_ksymbol, name),
238 },
239 .addr = prog_addrs[i],
240 .len = prog_lens[i],
241 .ksym_type = PERF_RECORD_KSYMBOL_TYPE_BPF,
242 .flags = 0,
243 };
244
245 name_len = synthesize_bpf_prog_name(ksymbol_event->name,
246 KSYM_NAME_LEN, info, btf, i);
247 ksymbol_event->header.size += PERF_ALIGN(name_len + 1,
248 sizeof(u64));
249
250 memset((void *)event + event->header.size, 0, machine->id_hdr_size);
251 event->header.size += machine->id_hdr_size;
252 err = perf_tool__process_synth_event(tool, event,
253 machine, process);
254 }
255
256 if (!opts->no_bpf_event) {
257 /* Synthesize PERF_RECORD_BPF_EVENT */
258 *bpf_event = (struct perf_record_bpf_event) {
259 .header = {
260 .type = PERF_RECORD_BPF_EVENT,
261 .size = sizeof(struct perf_record_bpf_event),
262 },
263 .type = PERF_BPF_EVENT_PROG_LOAD,
264 .flags = 0,
265 .id = info->id,
266 };
267 memcpy(bpf_event->tag, info->tag, BPF_TAG_SIZE);
268 memset((void *)event + event->header.size, 0, machine->id_hdr_size);
269 event->header.size += machine->id_hdr_size;
270
271 /* save bpf_prog_info to env */
272 info_node = malloc(sizeof(struct bpf_prog_info_node));
273 if (!info_node) {
274 err = -1;
275 goto out;
276 }
277
278 info_node->info_linear = info_linear;
279 perf_env__insert_bpf_prog_info(env, info_node);
280 info_linear = NULL;
281
282 /*
283 * process after saving bpf_prog_info to env, so that
284 * required information is ready for look up
285 */
286 err = perf_tool__process_synth_event(tool, event,
287 machine, process);
288 }
289
290out:
291 free(info_linear);
292 free(btf);
293 return err ? -1 : 0;
294}
295
296struct kallsyms_parse {
297 union perf_event *event;
298 perf_event__handler_t process;
299 struct machine *machine;
300 struct perf_tool *tool;
301};
302
303static int
304process_bpf_image(char *name, u64 addr, struct kallsyms_parse *data)
305{
306 struct machine *machine = data->machine;
307 union perf_event *event = data->event;
308 struct perf_record_ksymbol *ksymbol;
309 int len;
310
311 ksymbol = &event->ksymbol;
312
313 *ksymbol = (struct perf_record_ksymbol) {
314 .header = {
315 .type = PERF_RECORD_KSYMBOL,
316 .size = offsetof(struct perf_record_ksymbol, name),
317 },
318 .addr = addr,
319 .len = page_size,
320 .ksym_type = PERF_RECORD_KSYMBOL_TYPE_BPF,
321 .flags = 0,
322 };
323
324 len = scnprintf(ksymbol->name, KSYM_NAME_LEN, "%s", name);
325 ksymbol->header.size += PERF_ALIGN(len + 1, sizeof(u64));
326 memset((void *) event + event->header.size, 0, machine->id_hdr_size);
327 event->header.size += machine->id_hdr_size;
328
329 return perf_tool__process_synth_event(data->tool, event, machine,
330 data->process);
331}
332
333static int
334kallsyms_process_symbol(void *data, const char *_name,
335 char type __maybe_unused, u64 start)
336{
337 char disp[KSYM_NAME_LEN];
338 char *module, *name;
339 unsigned long id;
340 int err = 0;
341
342 module = strchr(_name, '\t');
343 if (!module)
344 return 0;
345
346 /* We are going after [bpf] module ... */
347 if (strcmp(module + 1, "[bpf]"))
348 return 0;
349
350 name = memdup(_name, (module - _name) + 1);
351 if (!name)
352 return -ENOMEM;
353
354 name[module - _name] = 0;
355
356 /* .. and only for trampolines and dispatchers */
357 if ((sscanf(name, "bpf_trampoline_%lu", &id) == 1) ||
358 (sscanf(name, "bpf_dispatcher_%s", disp) == 1))
359 err = process_bpf_image(name, start, data);
360
361 free(name);
362 return err;
363}
364
365int perf_event__synthesize_bpf_events(struct perf_session *session,
366 perf_event__handler_t process,
367 struct machine *machine,
368 struct record_opts *opts)
369{
370 const char *kallsyms_filename = "/proc/kallsyms";
371 struct kallsyms_parse arg;
372 union perf_event *event;
373 __u32 id = 0;
374 int err;
375 int fd;
376
377 event = malloc(sizeof(event->bpf) + KSYM_NAME_LEN + machine->id_hdr_size);
378 if (!event)
379 return -1;
380
381 /* Synthesize all the bpf programs in system. */
382 while (true) {
383 err = bpf_prog_get_next_id(id, &id);
384 if (err) {
385 if (errno == ENOENT) {
386 err = 0;
387 break;
388 }
389 pr_debug("%s: can't get next program: %s%s\n",
390 __func__, strerror(errno),
391 errno == EINVAL ? " -- kernel too old?" : "");
392 /* don't report error on old kernel or EPERM */
393 err = (errno == EINVAL || errno == EPERM) ? 0 : -1;
394 break;
395 }
396 fd = bpf_prog_get_fd_by_id(id);
397 if (fd < 0) {
398 pr_debug("%s: failed to get fd for prog_id %u\n",
399 __func__, id);
400 continue;
401 }
402
403 err = perf_event__synthesize_one_bpf_prog(session, process,
404 machine, fd,
405 event, opts);
406 close(fd);
407 if (err) {
408 /* do not return error for old kernel */
409 if (err == -2)
410 err = 0;
411 break;
412 }
413 }
414
415 /* Synthesize all the bpf images - trampolines/dispatchers. */
416 if (symbol_conf.kallsyms_name != NULL)
417 kallsyms_filename = symbol_conf.kallsyms_name;
418
419 arg = (struct kallsyms_parse) {
420 .event = event,
421 .process = process,
422 .machine = machine,
423 .tool = session->tool,
424 };
425
426 if (kallsyms__parse(kallsyms_filename, &arg, kallsyms_process_symbol)) {
427 pr_err("%s: failed to synthesize bpf images: %s\n",
428 __func__, strerror(errno));
429 }
430
431 free(event);
432 return err;
433}
434
435static void perf_env__add_bpf_info(struct perf_env *env, u32 id)
436{
437 struct bpf_prog_info_linear *info_linear;
438 struct bpf_prog_info_node *info_node;
439 struct btf *btf = NULL;
440 u64 arrays;
441 u32 btf_id;
442 int fd;
443
444 fd = bpf_prog_get_fd_by_id(id);
445 if (fd < 0)
446 return;
447
448 arrays = 1UL << BPF_PROG_INFO_JITED_KSYMS;
449 arrays |= 1UL << BPF_PROG_INFO_JITED_FUNC_LENS;
450 arrays |= 1UL << BPF_PROG_INFO_FUNC_INFO;
451 arrays |= 1UL << BPF_PROG_INFO_PROG_TAGS;
452 arrays |= 1UL << BPF_PROG_INFO_JITED_INSNS;
453 arrays |= 1UL << BPF_PROG_INFO_LINE_INFO;
454 arrays |= 1UL << BPF_PROG_INFO_JITED_LINE_INFO;
455
456 info_linear = bpf_program__get_prog_info_linear(fd, arrays);
457 if (IS_ERR_OR_NULL(info_linear)) {
458 pr_debug("%s: failed to get BPF program info. aborting\n", __func__);
459 goto out;
460 }
461
462 btf_id = info_linear->info.btf_id;
463
464 info_node = malloc(sizeof(struct bpf_prog_info_node));
465 if (info_node) {
466 info_node->info_linear = info_linear;
467 perf_env__insert_bpf_prog_info(env, info_node);
468 } else
469 free(info_linear);
470
471 if (btf_id == 0)
472 goto out;
473
474 if (btf__get_from_id(btf_id, &btf)) {
475 pr_debug("%s: failed to get BTF of id %u, aborting\n",
476 __func__, btf_id);
477 goto out;
478 }
479 perf_env__fetch_btf(env, btf_id, btf);
480
481out:
482 free(btf);
483 close(fd);
484}
485
486static int bpf_event__sb_cb(union perf_event *event, void *data)
487{
488 struct perf_env *env = data;
489
490 if (event->header.type != PERF_RECORD_BPF_EVENT)
491 return -1;
492
493 switch (event->bpf.type) {
494 case PERF_BPF_EVENT_PROG_LOAD:
495 perf_env__add_bpf_info(env, event->bpf.id);
496
497 case PERF_BPF_EVENT_PROG_UNLOAD:
498 /*
499 * Do not free bpf_prog_info and btf of the program here,
500 * as annotation still need them. They will be freed at
501 * the end of the session.
502 */
503 break;
504 default:
505 pr_debug("unexpected bpf event type of %d\n", event->bpf.type);
506 break;
507 }
508
509 return 0;
510}
511
512int evlist__add_bpf_sb_event(struct evlist *evlist, struct perf_env *env)
513{
514 struct perf_event_attr attr = {
515 .type = PERF_TYPE_SOFTWARE,
516 .config = PERF_COUNT_SW_DUMMY,
517 .sample_id_all = 1,
518 .watermark = 1,
519 .bpf_event = 1,
520 .size = sizeof(attr), /* to capture ABI version */
521 };
522
523 /*
524 * Older gcc versions don't support designated initializers, like above,
525 * for unnamed union members, such as the following:
526 */
527 attr.wakeup_watermark = 1;
528
529 return perf_evlist__add_sb_event(evlist, &attr, bpf_event__sb_cb, env);
530}
531
532void bpf_event__print_bpf_prog_info(struct bpf_prog_info *info,
533 struct perf_env *env,
534 FILE *fp)
535{
536 __u32 *prog_lens = (__u32 *)(uintptr_t)(info->jited_func_lens);
537 __u64 *prog_addrs = (__u64 *)(uintptr_t)(info->jited_ksyms);
538 char name[KSYM_NAME_LEN];
539 struct btf *btf = NULL;
540 u32 sub_prog_cnt, i;
541
542 sub_prog_cnt = info->nr_jited_ksyms;
543 if (sub_prog_cnt != info->nr_prog_tags ||
544 sub_prog_cnt != info->nr_jited_func_lens)
545 return;
546
547 if (info->btf_id) {
548 struct btf_node *node;
549
550 node = perf_env__find_btf(env, info->btf_id);
551 if (node)
552 btf = btf__new((__u8 *)(node->data),
553 node->data_size);
554 }
555
556 if (sub_prog_cnt == 1) {
557 synthesize_bpf_prog_name(name, KSYM_NAME_LEN, info, btf, 0);
558 fprintf(fp, "# bpf_prog_info %u: %s addr 0x%llx size %u\n",
559 info->id, name, prog_addrs[0], prog_lens[0]);
560 return;
561 }
562
563 fprintf(fp, "# bpf_prog_info %u:\n", info->id);
564 for (i = 0; i < sub_prog_cnt; i++) {
565 synthesize_bpf_prog_name(name, KSYM_NAME_LEN, info, btf, i);
566
567 fprintf(fp, "# \tsub_prog %u: %s addr 0x%llx size %u\n",
568 i, name, prog_addrs[i], prog_lens[i]);
569 }
570}