projects/linux·blob v5.17-rc4 · refs

669 lines · 17.1 KiB

1// SPDX-License-Identifier: GPL-2.0-only
2/* Copyright (c) 2016 Facebook
3 */
4#include <linux/bpf.h>
5#include <linux/jhash.h>
6#include <linux/filter.h>
7#include <linux/kernel.h>
8#include <linux/stacktrace.h>
9#include <linux/perf_event.h>
10#include <linux/btf_ids.h>
11#include <linux/buildid.h>
12#include "percpu_freelist.h"
13#include "mmap_unlock_work.h"
14
15#define STACK_CREATE_FLAG_MASK \
16 (BPF_F_NUMA_NODE | BPF_F_RDONLY | BPF_F_WRONLY | \
17 BPF_F_STACK_BUILD_ID)
18
19struct stack_map_bucket {
20 struct pcpu_freelist_node fnode;
21 u32 hash;
22 u32 nr;
23 u64 data[];
24};
25
26struct bpf_stack_map {
27 struct bpf_map map;
28 void *elems;
29 struct pcpu_freelist freelist;
30 u32 n_buckets;
31 struct stack_map_bucket *buckets[];
32};
33
34static inline bool stack_map_use_build_id(struct bpf_map *map)
35{
36 return (map->map_flags & BPF_F_STACK_BUILD_ID);
37}
38
39static inline int stack_map_data_size(struct bpf_map *map)
40{
41 return stack_map_use_build_id(map) ?
42 sizeof(struct bpf_stack_build_id) : sizeof(u64);
43}
44
45static int prealloc_elems_and_freelist(struct bpf_stack_map *smap)
46{
47 u64 elem_size = sizeof(struct stack_map_bucket) +
48 (u64)smap->map.value_size;
49 int err;
50
51 smap->elems = bpf_map_area_alloc(elem_size * smap->map.max_entries,
52 smap->map.numa_node);
53 if (!smap->elems)
54 return -ENOMEM;
55
56 err = pcpu_freelist_init(&smap->freelist);
57 if (err)
58 goto free_elems;
59
60 pcpu_freelist_populate(&smap->freelist, smap->elems, elem_size,
61 smap->map.max_entries);
62 return 0;
63
64free_elems:
65 bpf_map_area_free(smap->elems);
66 return err;
67}
68
69/* Called from syscall */
70static struct bpf_map *stack_map_alloc(union bpf_attr *attr)
71{
72 u32 value_size = attr->value_size;
73 struct bpf_stack_map *smap;
74 u64 cost, n_buckets;
75 int err;
76
77 if (!bpf_capable())
78 return ERR_PTR(-EPERM);
79
80 if (attr->map_flags & ~STACK_CREATE_FLAG_MASK)
81 return ERR_PTR(-EINVAL);
82
83 /* check sanity of attributes */
84 if (attr->max_entries == 0 || attr->key_size != 4 ||
85 value_size < 8 || value_size % 8)
86 return ERR_PTR(-EINVAL);
87
88 BUILD_BUG_ON(sizeof(struct bpf_stack_build_id) % sizeof(u64));
89 if (attr->map_flags & BPF_F_STACK_BUILD_ID) {
90 if (value_size % sizeof(struct bpf_stack_build_id) ||
91 value_size / sizeof(struct bpf_stack_build_id)
92 > sysctl_perf_event_max_stack)
93 return ERR_PTR(-EINVAL);
94 } else if (value_size / 8 > sysctl_perf_event_max_stack)
95 return ERR_PTR(-EINVAL);
96
97 /* hash table size must be power of 2 */
98 n_buckets = roundup_pow_of_two(attr->max_entries);
99 if (!n_buckets)
100 return ERR_PTR(-E2BIG);
101
102 cost = n_buckets * sizeof(struct stack_map_bucket *) + sizeof(*smap);
103 cost += n_buckets * (value_size + sizeof(struct stack_map_bucket));
104 smap = bpf_map_area_alloc(cost, bpf_map_attr_numa_node(attr));
105 if (!smap)
106 return ERR_PTR(-ENOMEM);
107
108 bpf_map_init_from_attr(&smap->map, attr);
109 smap->map.value_size = value_size;
110 smap->n_buckets = n_buckets;
111
112 err = get_callchain_buffers(sysctl_perf_event_max_stack);
113 if (err)
114 goto free_smap;
115
116 err = prealloc_elems_and_freelist(smap);
117 if (err)
118 goto put_buffers;
119
120 return &smap->map;
121
122put_buffers:
123 put_callchain_buffers();
124free_smap:
125 bpf_map_area_free(smap);
126 return ERR_PTR(err);
127}
128
129static void stack_map_get_build_id_offset(struct bpf_stack_build_id *id_offs,
130 u64 *ips, u32 trace_nr, bool user)
131{
132 int i;
133 struct mmap_unlock_irq_work *work = NULL;
134 bool irq_work_busy = bpf_mmap_unlock_get_irq_work(&work);
135 struct vm_area_struct *vma;
136
137 /* If the irq_work is in use, fall back to report ips. Same
138 * fallback is used for kernel stack (!user) on a stackmap with
139 * build_id.
140 */
141 if (!user || !current || !current->mm || irq_work_busy ||
142 !mmap_read_trylock(current->mm)) {
143 /* cannot access current->mm, fall back to ips */
144 for (i = 0; i < trace_nr; i++) {
145 id_offs[i].status = BPF_STACK_BUILD_ID_IP;
146 id_offs[i].ip = ips[i];
147 memset(id_offs[i].build_id, 0, BUILD_ID_SIZE_MAX);
148 }
149 return;
150 }
151
152 for (i = 0; i < trace_nr; i++) {
153 vma = find_vma(current->mm, ips[i]);
154 if (!vma || build_id_parse(vma, id_offs[i].build_id, NULL)) {
155 /* per entry fall back to ips */
156 id_offs[i].status = BPF_STACK_BUILD_ID_IP;
157 id_offs[i].ip = ips[i];
158 memset(id_offs[i].build_id, 0, BUILD_ID_SIZE_MAX);
159 continue;
160 }
161 id_offs[i].offset = (vma->vm_pgoff << PAGE_SHIFT) + ips[i]
162 - vma->vm_start;
163 id_offs[i].status = BPF_STACK_BUILD_ID_VALID;
164 }
165 bpf_mmap_unlock_mm(work, current->mm);
166}
167
168static struct perf_callchain_entry *
169get_callchain_entry_for_task(struct task_struct *task, u32 init_nr)
170{
171#ifdef CONFIG_STACKTRACE
172 struct perf_callchain_entry *entry;
173 int rctx;
174
175 entry = get_callchain_entry(&rctx);
176
177 if (!entry)
178 return NULL;
179
180 entry->nr = init_nr +
181 stack_trace_save_tsk(task, (unsigned long *)(entry->ip + init_nr),
182 sysctl_perf_event_max_stack - init_nr, 0);
183
184 /* stack_trace_save_tsk() works on unsigned long array, while
185 * perf_callchain_entry uses u64 array. For 32-bit systems, it is
186 * necessary to fix this mismatch.
187 */
188 if (__BITS_PER_LONG != 64) {
189 unsigned long *from = (unsigned long *) entry->ip;
190 u64 *to = entry->ip;
191 int i;
192
193 /* copy data from the end to avoid using extra buffer */
194 for (i = entry->nr - 1; i >= (int)init_nr; i--)
195 to[i] = (u64)(from[i]);
196 }
197
198 put_callchain_entry(rctx);
199
200 return entry;
201#else /* CONFIG_STACKTRACE */
202 return NULL;
203#endif
204}
205
206static long __bpf_get_stackid(struct bpf_map *map,
207 struct perf_callchain_entry *trace, u64 flags)
208{
209 struct bpf_stack_map *smap = container_of(map, struct bpf_stack_map, map);
210 struct stack_map_bucket *bucket, *new_bucket, *old_bucket;
211 u32 max_depth = map->value_size / stack_map_data_size(map);
212 /* stack_map_alloc() checks that max_depth <= sysctl_perf_event_max_stack */
213 u32 init_nr = sysctl_perf_event_max_stack - max_depth;
214 u32 skip = flags & BPF_F_SKIP_FIELD_MASK;
215 u32 hash, id, trace_nr, trace_len;
216 bool user = flags & BPF_F_USER_STACK;
217 u64 *ips;
218 bool hash_matches;
219
220 /* get_perf_callchain() guarantees that trace->nr >= init_nr
221 * and trace-nr <= sysctl_perf_event_max_stack, so trace_nr <= max_depth
222 */
223 trace_nr = trace->nr - init_nr;
224
225 if (trace_nr <= skip)
226 /* skipping more than usable stack trace */
227 return -EFAULT;
228
229 trace_nr -= skip;
230 trace_len = trace_nr * sizeof(u64);
231 ips = trace->ip + skip + init_nr;
232 hash = jhash2((u32 *)ips, trace_len / sizeof(u32), 0);
233 id = hash & (smap->n_buckets - 1);
234 bucket = READ_ONCE(smap->buckets[id]);
235
236 hash_matches = bucket && bucket->hash == hash;
237 /* fast cmp */
238 if (hash_matches && flags & BPF_F_FAST_STACK_CMP)
239 return id;
240
241 if (stack_map_use_build_id(map)) {
242 /* for build_id+offset, pop a bucket before slow cmp */
243 new_bucket = (struct stack_map_bucket *)
244 pcpu_freelist_pop(&smap->freelist);
245 if (unlikely(!new_bucket))
246 return -ENOMEM;
247 new_bucket->nr = trace_nr;
248 stack_map_get_build_id_offset(
249 (struct bpf_stack_build_id *)new_bucket->data,
250 ips, trace_nr, user);
251 trace_len = trace_nr * sizeof(struct bpf_stack_build_id);
252 if (hash_matches && bucket->nr == trace_nr &&
253 memcmp(bucket->data, new_bucket->data, trace_len) == 0) {
254 pcpu_freelist_push(&smap->freelist, &new_bucket->fnode);
255 return id;
256 }
257 if (bucket && !(flags & BPF_F_REUSE_STACKID)) {
258 pcpu_freelist_push(&smap->freelist, &new_bucket->fnode);
259 return -EEXIST;
260 }
261 } else {
262 if (hash_matches && bucket->nr == trace_nr &&
263 memcmp(bucket->data, ips, trace_len) == 0)
264 return id;
265 if (bucket && !(flags & BPF_F_REUSE_STACKID))
266 return -EEXIST;
267
268 new_bucket = (struct stack_map_bucket *)
269 pcpu_freelist_pop(&smap->freelist);
270 if (unlikely(!new_bucket))
271 return -ENOMEM;
272 memcpy(new_bucket->data, ips, trace_len);
273 }
274
275 new_bucket->hash = hash;
276 new_bucket->nr = trace_nr;
277
278 old_bucket = xchg(&smap->buckets[id], new_bucket);
279 if (old_bucket)
280 pcpu_freelist_push(&smap->freelist, &old_bucket->fnode);
281 return id;
282}
283
284BPF_CALL_3(bpf_get_stackid, struct pt_regs *, regs, struct bpf_map *, map,
285 u64, flags)
286{
287 u32 max_depth = map->value_size / stack_map_data_size(map);
288 /* stack_map_alloc() checks that max_depth <= sysctl_perf_event_max_stack */
289 u32 init_nr = sysctl_perf_event_max_stack - max_depth;
290 bool user = flags & BPF_F_USER_STACK;
291 struct perf_callchain_entry *trace;
292 bool kernel = !user;
293
294 if (unlikely(flags & ~(BPF_F_SKIP_FIELD_MASK | BPF_F_USER_STACK |
295 BPF_F_FAST_STACK_CMP | BPF_F_REUSE_STACKID)))
296 return -EINVAL;
297
298 trace = get_perf_callchain(regs, init_nr, kernel, user,
299 sysctl_perf_event_max_stack, false, false);
300
301 if (unlikely(!trace))
302 /* couldn't fetch the stack trace */
303 return -EFAULT;
304
305 return __bpf_get_stackid(map, trace, flags);
306}
307
308const struct bpf_func_proto bpf_get_stackid_proto = {
309 .func = bpf_get_stackid,
310 .gpl_only = true,
311 .ret_type = RET_INTEGER,
312 .arg1_type = ARG_PTR_TO_CTX,
313 .arg2_type = ARG_CONST_MAP_PTR,
314 .arg3_type = ARG_ANYTHING,
315};
316
317static __u64 count_kernel_ip(struct perf_callchain_entry *trace)
318{
319 __u64 nr_kernel = 0;
320
321 while (nr_kernel < trace->nr) {
322 if (trace->ip[nr_kernel] == PERF_CONTEXT_USER)
323 break;
324 nr_kernel++;
325 }
326 return nr_kernel;
327}
328
329BPF_CALL_3(bpf_get_stackid_pe, struct bpf_perf_event_data_kern *, ctx,
330 struct bpf_map *, map, u64, flags)
331{
332 struct perf_event *event = ctx->event;
333 struct perf_callchain_entry *trace;
334 bool kernel, user;
335 __u64 nr_kernel;
336 int ret;
337
338 /* perf_sample_data doesn't have callchain, use bpf_get_stackid */
339 if (!(event->attr.sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY))
340 return bpf_get_stackid((unsigned long)(ctx->regs),
341 (unsigned long) map, flags, 0, 0);
342
343 if (unlikely(flags & ~(BPF_F_SKIP_FIELD_MASK | BPF_F_USER_STACK |
344 BPF_F_FAST_STACK_CMP | BPF_F_REUSE_STACKID)))
345 return -EINVAL;
346
347 user = flags & BPF_F_USER_STACK;
348 kernel = !user;
349
350 trace = ctx->data->callchain;
351 if (unlikely(!trace))
352 return -EFAULT;
353
354 nr_kernel = count_kernel_ip(trace);
355
356 if (kernel) {
357 __u64 nr = trace->nr;
358
359 trace->nr = nr_kernel;
360 ret = __bpf_get_stackid(map, trace, flags);
361
362 /* restore nr */
363 trace->nr = nr;
364 } else { /* user */
365 u64 skip = flags & BPF_F_SKIP_FIELD_MASK;
366
367 skip += nr_kernel;
368 if (skip > BPF_F_SKIP_FIELD_MASK)
369 return -EFAULT;
370
371 flags = (flags & ~BPF_F_SKIP_FIELD_MASK) | skip;
372 ret = __bpf_get_stackid(map, trace, flags);
373 }
374 return ret;
375}
376
377const struct bpf_func_proto bpf_get_stackid_proto_pe = {
378 .func = bpf_get_stackid_pe,
379 .gpl_only = false,
380 .ret_type = RET_INTEGER,
381 .arg1_type = ARG_PTR_TO_CTX,
382 .arg2_type = ARG_CONST_MAP_PTR,
383 .arg3_type = ARG_ANYTHING,
384};
385
386static long __bpf_get_stack(struct pt_regs *regs, struct task_struct *task,
387 struct perf_callchain_entry *trace_in,
388 void *buf, u32 size, u64 flags)
389{
390 u32 init_nr, trace_nr, copy_len, elem_size, num_elem;
391 bool user_build_id = flags & BPF_F_USER_BUILD_ID;
392 u32 skip = flags & BPF_F_SKIP_FIELD_MASK;
393 bool user = flags & BPF_F_USER_STACK;
394 struct perf_callchain_entry *trace;
395 bool kernel = !user;
396 int err = -EINVAL;
397 u64 *ips;
398
399 if (unlikely(flags & ~(BPF_F_SKIP_FIELD_MASK | BPF_F_USER_STACK |
400 BPF_F_USER_BUILD_ID)))
401 goto clear;
402 if (kernel && user_build_id)
403 goto clear;
404
405 elem_size = (user && user_build_id) ? sizeof(struct bpf_stack_build_id)
406 : sizeof(u64);
407 if (unlikely(size % elem_size))
408 goto clear;
409
410 /* cannot get valid user stack for task without user_mode regs */
411 if (task && user && !user_mode(regs))
412 goto err_fault;
413
414 num_elem = size / elem_size;
415 if (sysctl_perf_event_max_stack < num_elem)
416 init_nr = 0;
417 else
418 init_nr = sysctl_perf_event_max_stack - num_elem;
419
420 if (trace_in)
421 trace = trace_in;
422 else if (kernel && task)
423 trace = get_callchain_entry_for_task(task, init_nr);
424 else
425 trace = get_perf_callchain(regs, init_nr, kernel, user,
426 sysctl_perf_event_max_stack,
427 false, false);
428 if (unlikely(!trace))
429 goto err_fault;
430
431 trace_nr = trace->nr - init_nr;
432 if (trace_nr < skip)
433 goto err_fault;
434
435 trace_nr -= skip;
436 trace_nr = (trace_nr <= num_elem) ? trace_nr : num_elem;
437 copy_len = trace_nr * elem_size;
438 ips = trace->ip + skip + init_nr;
439 if (user && user_build_id)
440 stack_map_get_build_id_offset(buf, ips, trace_nr, user);
441 else
442 memcpy(buf, ips, copy_len);
443
444 if (size > copy_len)
445 memset(buf + copy_len, 0, size - copy_len);
446 return copy_len;
447
448err_fault:
449 err = -EFAULT;
450clear:
451 memset(buf, 0, size);
452 return err;
453}
454
455BPF_CALL_4(bpf_get_stack, struct pt_regs *, regs, void *, buf, u32, size,
456 u64, flags)
457{
458 return __bpf_get_stack(regs, NULL, NULL, buf, size, flags);
459}
460
461const struct bpf_func_proto bpf_get_stack_proto = {
462 .func = bpf_get_stack,
463 .gpl_only = true,
464 .ret_type = RET_INTEGER,
465 .arg1_type = ARG_PTR_TO_CTX,
466 .arg2_type = ARG_PTR_TO_UNINIT_MEM,
467 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
468 .arg4_type = ARG_ANYTHING,
469};
470
471BPF_CALL_4(bpf_get_task_stack, struct task_struct *, task, void *, buf,
472 u32, size, u64, flags)
473{
474 struct pt_regs *regs;
475 long res = -EINVAL;
476
477 if (!try_get_task_stack(task))
478 return -EFAULT;
479
480 regs = task_pt_regs(task);
481 if (regs)
482 res = __bpf_get_stack(regs, task, NULL, buf, size, flags);
483 put_task_stack(task);
484
485 return res;
486}
487
488const struct bpf_func_proto bpf_get_task_stack_proto = {
489 .func = bpf_get_task_stack,
490 .gpl_only = false,
491 .ret_type = RET_INTEGER,
492 .arg1_type = ARG_PTR_TO_BTF_ID,
493 .arg1_btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK],
494 .arg2_type = ARG_PTR_TO_UNINIT_MEM,
495 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
496 .arg4_type = ARG_ANYTHING,
497};
498
499BPF_CALL_4(bpf_get_stack_pe, struct bpf_perf_event_data_kern *, ctx,
500 void *, buf, u32, size, u64, flags)
501{
502 struct pt_regs *regs = (struct pt_regs *)(ctx->regs);
503 struct perf_event *event = ctx->event;
504 struct perf_callchain_entry *trace;
505 bool kernel, user;
506 int err = -EINVAL;
507 __u64 nr_kernel;
508
509 if (!(event->attr.sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY))
510 return __bpf_get_stack(regs, NULL, NULL, buf, size, flags);
511
512 if (unlikely(flags & ~(BPF_F_SKIP_FIELD_MASK | BPF_F_USER_STACK |
513 BPF_F_USER_BUILD_ID)))
514 goto clear;
515
516 user = flags & BPF_F_USER_STACK;
517 kernel = !user;
518
519 err = -EFAULT;
520 trace = ctx->data->callchain;
521 if (unlikely(!trace))
522 goto clear;
523
524 nr_kernel = count_kernel_ip(trace);
525
526 if (kernel) {
527 __u64 nr = trace->nr;
528
529 trace->nr = nr_kernel;
530 err = __bpf_get_stack(regs, NULL, trace, buf, size, flags);
531
532 /* restore nr */
533 trace->nr = nr;
534 } else { /* user */
535 u64 skip = flags & BPF_F_SKIP_FIELD_MASK;
536
537 skip += nr_kernel;
538 if (skip > BPF_F_SKIP_FIELD_MASK)
539 goto clear;
540
541 flags = (flags & ~BPF_F_SKIP_FIELD_MASK) | skip;
542 err = __bpf_get_stack(regs, NULL, trace, buf, size, flags);
543 }
544 return err;
545
546clear:
547 memset(buf, 0, size);
548 return err;
549
550}
551
552const struct bpf_func_proto bpf_get_stack_proto_pe = {
553 .func = bpf_get_stack_pe,
554 .gpl_only = true,
555 .ret_type = RET_INTEGER,
556 .arg1_type = ARG_PTR_TO_CTX,
557 .arg2_type = ARG_PTR_TO_UNINIT_MEM,
558 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
559 .arg4_type = ARG_ANYTHING,
560};
561
562/* Called from eBPF program */
563static void *stack_map_lookup_elem(struct bpf_map *map, void *key)
564{
565 return ERR_PTR(-EOPNOTSUPP);
566}
567
568/* Called from syscall */
569int bpf_stackmap_copy(struct bpf_map *map, void *key, void *value)
570{
571 struct bpf_stack_map *smap = container_of(map, struct bpf_stack_map, map);
572 struct stack_map_bucket *bucket, *old_bucket;
573 u32 id = *(u32 *)key, trace_len;
574
575 if (unlikely(id >= smap->n_buckets))
576 return -ENOENT;
577
578 bucket = xchg(&smap->buckets[id], NULL);
579 if (!bucket)
580 return -ENOENT;
581
582 trace_len = bucket->nr * stack_map_data_size(map);
583 memcpy(value, bucket->data, trace_len);
584 memset(value + trace_len, 0, map->value_size - trace_len);
585
586 old_bucket = xchg(&smap->buckets[id], bucket);
587 if (old_bucket)
588 pcpu_freelist_push(&smap->freelist, &old_bucket->fnode);
589 return 0;
590}
591
592static int stack_map_get_next_key(struct bpf_map *map, void *key,
593 void *next_key)
594{
595 struct bpf_stack_map *smap = container_of(map,
596 struct bpf_stack_map, map);
597 u32 id;
598
599 WARN_ON_ONCE(!rcu_read_lock_held());
600
601 if (!key) {
602 id = 0;
603 } else {
604 id = *(u32 *)key;
605 if (id >= smap->n_buckets || !smap->buckets[id])
606 id = 0;
607 else
608 id++;
609 }
610
611 while (id < smap->n_buckets && !smap->buckets[id])
612 id++;
613
614 if (id >= smap->n_buckets)
615 return -ENOENT;
616
617 *(u32 *)next_key = id;
618 return 0;
619}
620
621static int stack_map_update_elem(struct bpf_map *map, void *key, void *value,
622 u64 map_flags)
623{
624 return -EINVAL;
625}
626
627/* Called from syscall or from eBPF program */
628static int stack_map_delete_elem(struct bpf_map *map, void *key)
629{
630 struct bpf_stack_map *smap = container_of(map, struct bpf_stack_map, map);
631 struct stack_map_bucket *old_bucket;
632 u32 id = *(u32 *)key;
633
634 if (unlikely(id >= smap->n_buckets))
635 return -E2BIG;
636
637 old_bucket = xchg(&smap->buckets[id], NULL);
638 if (old_bucket) {
639 pcpu_freelist_push(&smap->freelist, &old_bucket->fnode);
640 return 0;
641 } else {
642 return -ENOENT;
643 }
644}
645
646/* Called when map->refcnt goes to zero, either from workqueue or from syscall */
647static void stack_map_free(struct bpf_map *map)
648{
649 struct bpf_stack_map *smap = container_of(map, struct bpf_stack_map, map);
650
651 bpf_map_area_free(smap->elems);
652 pcpu_freelist_destroy(&smap->freelist);
653 bpf_map_area_free(smap);
654 put_callchain_buffers();
655}
656
657static int stack_trace_map_btf_id;
658const struct bpf_map_ops stack_trace_map_ops = {
659 .map_meta_equal = bpf_map_meta_equal,
660 .map_alloc = stack_map_alloc,
661 .map_free = stack_map_free,
662 .map_get_next_key = stack_map_get_next_key,
663 .map_lookup_elem = stack_map_lookup_elem,
664 .map_update_elem = stack_map_update_elem,
665 .map_delete_elem = stack_map_delete_elem,
666 .map_check_btf = map_check_no_btf,
667 .map_btf_name = "bpf_stack_map",
668 .map_btf_id = &stack_trace_map_btf_id,
669};