1 /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
2 
3 /*
4  * Internal libbpf helpers.
5  *
6  * Copyright (c) 2019 Facebook
7  */
8 
9 #ifndef __LIBBPF_LIBBPF_INTERNAL_H
10 #define __LIBBPF_LIBBPF_INTERNAL_H
11 
12 #include <stdlib.h>
13 #include <limits.h>
14 #include <errno.h>
15 #include <linux/err.h>
16 #include <fcntl.h>
17 #include <unistd.h>
18 #include "relo_core.h"
19 
20 /* make sure libbpf doesn't use kernel-only integer typedefs */
21 #pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
22 
23 /* prevent accidental re-addition of reallocarray() */
24 #pragma GCC poison reallocarray
25 
26 #include "libbpf.h"
27 #include "btf.h"
28 
29 #ifndef EM_BPF
30 #define EM_BPF 247
31 #endif
32 
33 #ifndef R_BPF_64_64
34 #define R_BPF_64_64 1
35 #endif
36 #ifndef R_BPF_64_ABS64
37 #define R_BPF_64_ABS64 2
38 #endif
39 #ifndef R_BPF_64_ABS32
40 #define R_BPF_64_ABS32 3
41 #endif
42 #ifndef R_BPF_64_32
43 #define R_BPF_64_32 10
44 #endif
45 
46 #ifndef SHT_LLVM_ADDRSIG
47 #define SHT_LLVM_ADDRSIG 0x6FFF4C03
48 #endif
49 
50 /* if libelf is old and doesn't support mmap(), fall back to read() */
51 #ifndef ELF_C_READ_MMAP
52 #define ELF_C_READ_MMAP ELF_C_READ
53 #endif
54 
55 /* Older libelf all end up in this expression, for both 32 and 64 bit */
56 #ifndef ELF64_ST_VISIBILITY
57 #define ELF64_ST_VISIBILITY(o) ((o) & 0x03)
58 #endif
59 
60 #define BTF_INFO_ENC(kind, kind_flag, vlen) \
61 	((!!(kind_flag) << 31) | ((kind) << 24) | ((vlen) & BTF_MAX_VLEN))
62 #define BTF_TYPE_ENC(name, info, size_or_type) (name), (info), (size_or_type)
63 #define BTF_INT_ENC(encoding, bits_offset, nr_bits) \
64 	((encoding) << 24 | (bits_offset) << 16 | (nr_bits))
65 #define BTF_TYPE_INT_ENC(name, encoding, bits_offset, bits, sz) \
66 	BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_INT, 0, 0), sz), \
67 	BTF_INT_ENC(encoding, bits_offset, bits)
68 #define BTF_MEMBER_ENC(name, type, bits_offset) (name), (type), (bits_offset)
69 #define BTF_PARAM_ENC(name, type) (name), (type)
70 #define BTF_VAR_SECINFO_ENC(type, offset, size) (type), (offset), (size)
71 #define BTF_TYPE_FLOAT_ENC(name, sz) \
72 	BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_FLOAT, 0, 0), sz)
73 #define BTF_TYPE_DECL_TAG_ENC(value, type, component_idx) \
74 	BTF_TYPE_ENC(value, BTF_INFO_ENC(BTF_KIND_DECL_TAG, 0, 0), type), (component_idx)
75 #define BTF_TYPE_TYPE_TAG_ENC(value, type) \
76 	BTF_TYPE_ENC(value, BTF_INFO_ENC(BTF_KIND_TYPE_TAG, 0, 0), type)
77 
78 #ifndef likely
79 #define likely(x) __builtin_expect(!!(x), 1)
80 #endif
81 #ifndef unlikely
82 #define unlikely(x) __builtin_expect(!!(x), 0)
83 #endif
84 #ifndef min
85 # define min(x, y) ((x) < (y) ? (x) : (y))
86 #endif
87 #ifndef max
88 # define max(x, y) ((x) < (y) ? (y) : (x))
89 #endif
90 #ifndef offsetofend
91 # define offsetofend(TYPE, FIELD) \
92 	(offsetof(TYPE, FIELD) + sizeof(((TYPE *)0)->FIELD))
93 #endif
94 #ifndef __alias
95 #define __alias(symbol) __attribute__((alias(#symbol)))
96 #endif
97 
98 /* Check whether a string `str` has prefix `pfx`, regardless if `pfx` is
99  * a string literal known at compilation time or char * pointer known only at
100  * runtime.
101  */
102 #define str_has_pfx(str, pfx) \
103 	(strncmp(str, pfx, __builtin_constant_p(pfx) ? sizeof(pfx) - 1 : strlen(pfx)) == 0)
104 
105 /* suffix check */
str_has_sfx(const char * str,const char * sfx)106 static inline bool str_has_sfx(const char *str, const char *sfx)
107 {
108 	size_t str_len = strlen(str);
109 	size_t sfx_len = strlen(sfx);
110 
111 	if (sfx_len > str_len)
112 		return false;
113 	return strcmp(str + str_len - sfx_len, sfx) == 0;
114 }
115 
116 /* Symbol versioning is different between static and shared library.
117  * Properly versioned symbols are needed for shared library, but
118  * only the symbol of the new version is needed for static library.
119  * Starting with GNU C 10, use symver attribute instead of .symver assembler
120  * directive, which works better with GCC LTO builds.
121  */
122 #if defined(SHARED) && defined(__GNUC__) && __GNUC__ >= 10
123 
124 #define DEFAULT_VERSION(internal_name, api_name, version) \
125 	__attribute__((symver(#api_name "@@" #version)))
126 #define COMPAT_VERSION(internal_name, api_name, version) \
127 	__attribute__((symver(#api_name "@" #version)))
128 
129 #elif defined(SHARED)
130 
131 #define COMPAT_VERSION(internal_name, api_name, version) \
132 	asm(".symver " #internal_name "," #api_name "@" #version);
133 #define DEFAULT_VERSION(internal_name, api_name, version) \
134 	asm(".symver " #internal_name "," #api_name "@@" #version);
135 
136 #else /* !SHARED */
137 
138 #define COMPAT_VERSION(internal_name, api_name, version)
139 #define DEFAULT_VERSION(internal_name, api_name, version) \
140 	extern typeof(internal_name) api_name \
141 	__attribute__((alias(#internal_name)));
142 
143 #endif
144 
145 extern void libbpf_print(enum libbpf_print_level level,
146 			 const char *format, ...)
147 	__attribute__((format(printf, 2, 3)));
148 
149 #define __pr(level, fmt, ...)	\
150 do {				\
151 	libbpf_print(level, "libbpf: " fmt, ##__VA_ARGS__);	\
152 } while (0)
153 
154 #define pr_warn(fmt, ...)	__pr(LIBBPF_WARN, fmt, ##__VA_ARGS__)
155 #define pr_info(fmt, ...)	__pr(LIBBPF_INFO, fmt, ##__VA_ARGS__)
156 #define pr_debug(fmt, ...)	__pr(LIBBPF_DEBUG, fmt, ##__VA_ARGS__)
157 
158 #ifndef __has_builtin
159 #define __has_builtin(x) 0
160 #endif
161 
162 struct bpf_link {
163 	int (*detach)(struct bpf_link *link);
164 	void (*dealloc)(struct bpf_link *link);
165 	char *pin_path;		/* NULL, if not pinned */
166 	int fd;			/* hook FD, -1 if not applicable */
167 	bool disconnected;
168 };
169 
170 /*
171  * Re-implement glibc's reallocarray() for libbpf internal-only use.
172  * reallocarray(), unfortunately, is not available in all versions of glibc,
173  * so requires extra feature detection and using reallocarray() stub from
174  * <tools/libc_compat.h> and COMPAT_NEED_REALLOCARRAY. All this complicates
175  * build of libbpf unnecessarily and is just a maintenance burden. Instead,
176  * it's trivial to implement libbpf-specific internal version and use it
177  * throughout libbpf.
178  */
libbpf_reallocarray(void * ptr,size_t nmemb,size_t size)179 static inline void *libbpf_reallocarray(void *ptr, size_t nmemb, size_t size)
180 {
181 	size_t total;
182 
183 #if __has_builtin(__builtin_mul_overflow)
184 	if (unlikely(__builtin_mul_overflow(nmemb, size, &total)))
185 		return NULL;
186 #else
187 	if (size == 0 || nmemb > ULONG_MAX / size)
188 		return NULL;
189 	total = nmemb * size;
190 #endif
191 	return realloc(ptr, total);
192 }
193 
194 /* Copy up to sz - 1 bytes from zero-terminated src string and ensure that dst
195  * is zero-terminated string no matter what (unless sz == 0, in which case
196  * it's a no-op). It's conceptually close to FreeBSD's strlcpy(), but differs
197  * in what is returned. Given this is internal helper, it's trivial to extend
198  * this, when necessary. Use this instead of strncpy inside libbpf source code.
199  */
libbpf_strlcpy(char * dst,const char * src,size_t sz)200 static inline void libbpf_strlcpy(char *dst, const char *src, size_t sz)
201 {
202 	size_t i;
203 
204 	if (sz == 0)
205 		return;
206 
207 	sz--;
208 	for (i = 0; i < sz && src[i]; i++)
209 		dst[i] = src[i];
210 	dst[i] = '\0';
211 }
212 
213 __u32 get_kernel_version(void);
214 
215 struct btf;
216 struct btf_type;
217 
218 struct btf_type *btf_type_by_id(const struct btf *btf, __u32 type_id);
219 const char *btf_kind_str(const struct btf_type *t);
220 const struct btf_type *skip_mods_and_typedefs(const struct btf *btf, __u32 id, __u32 *res_id);
221 
btf_func_linkage(const struct btf_type * t)222 static inline enum btf_func_linkage btf_func_linkage(const struct btf_type *t)
223 {
224 	return (enum btf_func_linkage)(int)btf_vlen(t);
225 }
226 
btf_type_info(int kind,int vlen,int kflag)227 static inline __u32 btf_type_info(int kind, int vlen, int kflag)
228 {
229 	return (kflag << 31) | (kind << 24) | vlen;
230 }
231 
232 enum map_def_parts {
233 	MAP_DEF_MAP_TYPE	= 0x001,
234 	MAP_DEF_KEY_TYPE	= 0x002,
235 	MAP_DEF_KEY_SIZE	= 0x004,
236 	MAP_DEF_VALUE_TYPE	= 0x008,
237 	MAP_DEF_VALUE_SIZE	= 0x010,
238 	MAP_DEF_MAX_ENTRIES	= 0x020,
239 	MAP_DEF_MAP_FLAGS	= 0x040,
240 	MAP_DEF_NUMA_NODE	= 0x080,
241 	MAP_DEF_PINNING		= 0x100,
242 	MAP_DEF_INNER_MAP	= 0x200,
243 	MAP_DEF_MAP_EXTRA	= 0x400,
244 
245 	MAP_DEF_ALL		= 0x7ff, /* combination of all above */
246 };
247 
248 struct btf_map_def {
249 	enum map_def_parts parts;
250 	__u32 map_type;
251 	__u32 key_type_id;
252 	__u32 key_size;
253 	__u32 value_type_id;
254 	__u32 value_size;
255 	__u32 max_entries;
256 	__u32 map_flags;
257 	__u32 numa_node;
258 	__u32 pinning;
259 	__u64 map_extra;
260 };
261 
262 int parse_btf_map_def(const char *map_name, struct btf *btf,
263 		      const struct btf_type *def_t, bool strict,
264 		      struct btf_map_def *map_def, struct btf_map_def *inner_def);
265 
266 void *libbpf_add_mem(void **data, size_t *cap_cnt, size_t elem_sz,
267 		     size_t cur_cnt, size_t max_cnt, size_t add_cnt);
268 int libbpf_ensure_mem(void **data, size_t *cap_cnt, size_t elem_sz, size_t need_cnt);
269 
libbpf_is_mem_zeroed(const char * p,ssize_t len)270 static inline bool libbpf_is_mem_zeroed(const char *p, ssize_t len)
271 {
272 	while (len > 0) {
273 		if (*p)
274 			return false;
275 		p++;
276 		len--;
277 	}
278 	return true;
279 }
280 
libbpf_validate_opts(const char * opts,size_t opts_sz,size_t user_sz,const char * type_name)281 static inline bool libbpf_validate_opts(const char *opts,
282 					size_t opts_sz, size_t user_sz,
283 					const char *type_name)
284 {
285 	if (user_sz < sizeof(size_t)) {
286 		pr_warn("%s size (%zu) is too small\n", type_name, user_sz);
287 		return false;
288 	}
289 	if (!libbpf_is_mem_zeroed(opts + opts_sz, (ssize_t)user_sz - opts_sz)) {
290 		pr_warn("%s has non-zero extra bytes\n", type_name);
291 		return false;
292 	}
293 	return true;
294 }
295 
296 #define OPTS_VALID(opts, type)						      \
297 	(!(opts) || libbpf_validate_opts((const char *)opts,		      \
298 					 offsetofend(struct type,	      \
299 						     type##__last_field),     \
300 					 (opts)->sz, #type))
301 #define OPTS_HAS(opts, field) \
302 	((opts) && opts->sz >= offsetofend(typeof(*(opts)), field))
303 #define OPTS_GET(opts, field, fallback_value) \
304 	(OPTS_HAS(opts, field) ? (opts)->field : fallback_value)
305 #define OPTS_SET(opts, field, value)		\
306 	do {					\
307 		if (OPTS_HAS(opts, field))	\
308 			(opts)->field = value;	\
309 	} while (0)
310 
311 #define OPTS_ZEROED(opts, last_nonzero_field)				      \
312 ({									      \
313 	ssize_t __off = offsetofend(typeof(*(opts)), last_nonzero_field);     \
314 	!(opts) || libbpf_is_mem_zeroed((const void *)opts + __off,	      \
315 					(opts)->sz - __off);		      \
316 })
317 
318 enum kern_feature_id {
319 	/* v4.14: kernel support for program & map names. */
320 	FEAT_PROG_NAME,
321 	/* v5.2: kernel support for global data sections. */
322 	FEAT_GLOBAL_DATA,
323 	/* BTF support */
324 	FEAT_BTF,
325 	/* BTF_KIND_FUNC and BTF_KIND_FUNC_PROTO support */
326 	FEAT_BTF_FUNC,
327 	/* BTF_KIND_VAR and BTF_KIND_DATASEC support */
328 	FEAT_BTF_DATASEC,
329 	/* BTF_FUNC_GLOBAL is supported */
330 	FEAT_BTF_GLOBAL_FUNC,
331 	/* BPF_F_MMAPABLE is supported for arrays */
332 	FEAT_ARRAY_MMAP,
333 	/* kernel support for expected_attach_type in BPF_PROG_LOAD */
334 	FEAT_EXP_ATTACH_TYPE,
335 	/* bpf_probe_read_{kernel,user}[_str] helpers */
336 	FEAT_PROBE_READ_KERN,
337 	/* BPF_PROG_BIND_MAP is supported */
338 	FEAT_PROG_BIND_MAP,
339 	/* Kernel support for module BTFs */
340 	FEAT_MODULE_BTF,
341 	/* BTF_KIND_FLOAT support */
342 	FEAT_BTF_FLOAT,
343 	/* BPF perf link support */
344 	FEAT_PERF_LINK,
345 	/* BTF_KIND_DECL_TAG support */
346 	FEAT_BTF_DECL_TAG,
347 	/* BTF_KIND_TYPE_TAG support */
348 	FEAT_BTF_TYPE_TAG,
349 	/* memcg-based accounting for BPF maps and progs */
350 	FEAT_MEMCG_ACCOUNT,
351 	/* BPF cookie (bpf_get_attach_cookie() BPF helper) support */
352 	FEAT_BPF_COOKIE,
353 	/* BTF_KIND_ENUM64 support and BTF_KIND_ENUM kflag support */
354 	FEAT_BTF_ENUM64,
355 	/* Kernel uses syscall wrapper (CONFIG_ARCH_HAS_SYSCALL_WRAPPER) */
356 	FEAT_SYSCALL_WRAPPER,
357 	__FEAT_CNT,
358 };
359 
360 int probe_memcg_account(void);
361 bool kernel_supports(const struct bpf_object *obj, enum kern_feature_id feat_id);
362 int bump_rlimit_memlock(void);
363 
364 int parse_cpu_mask_str(const char *s, bool **mask, int *mask_sz);
365 int parse_cpu_mask_file(const char *fcpu, bool **mask, int *mask_sz);
366 int libbpf__load_raw_btf(const char *raw_types, size_t types_len,
367 			 const char *str_sec, size_t str_len);
368 int btf_load_into_kernel(struct btf *btf, char *log_buf, size_t log_sz, __u32 log_level);
369 
370 struct btf *btf_get_from_fd(int btf_fd, struct btf *base_btf);
371 void btf_get_kernel_prefix_kind(enum bpf_attach_type attach_type,
372 				const char **prefix, int *kind);
373 
374 struct btf_ext_info {
375 	/*
376 	 * info points to the individual info section (e.g. func_info and
377 	 * line_info) from the .BTF.ext. It does not include the __u32 rec_size.
378 	 */
379 	void *info;
380 	__u32 rec_size;
381 	__u32 len;
382 	/* optional (maintained internally by libbpf) mapping between .BTF.ext
383 	 * section and corresponding ELF section. This is used to join
384 	 * information like CO-RE relocation records with corresponding BPF
385 	 * programs defined in ELF sections
386 	 */
387 	__u32 *sec_idxs;
388 	int sec_cnt;
389 };
390 
391 #define for_each_btf_ext_sec(seg, sec)					\
392 	for (sec = (seg)->info;						\
393 	     (void *)sec < (seg)->info + (seg)->len;			\
394 	     sec = (void *)sec + sizeof(struct btf_ext_info_sec) +	\
395 		   (seg)->rec_size * sec->num_info)
396 
397 #define for_each_btf_ext_rec(seg, sec, i, rec)				\
398 	for (i = 0, rec = (void *)&(sec)->data;				\
399 	     i < (sec)->num_info;					\
400 	     i++, rec = (void *)rec + (seg)->rec_size)
401 
402 /*
403  * The .BTF.ext ELF section layout defined as
404  *   struct btf_ext_header
405  *   func_info subsection
406  *
407  * The func_info subsection layout:
408  *   record size for struct bpf_func_info in the func_info subsection
409  *   struct btf_sec_func_info for section #1
410  *   a list of bpf_func_info records for section #1
411  *     where struct bpf_func_info mimics one in include/uapi/linux/bpf.h
412  *     but may not be identical
413  *   struct btf_sec_func_info for section #2
414  *   a list of bpf_func_info records for section #2
415  *   ......
416  *
417  * Note that the bpf_func_info record size in .BTF.ext may not
418  * be the same as the one defined in include/uapi/linux/bpf.h.
419  * The loader should ensure that record_size meets minimum
420  * requirement and pass the record as is to the kernel. The
421  * kernel will handle the func_info properly based on its contents.
422  */
423 struct btf_ext_header {
424 	__u16	magic;
425 	__u8	version;
426 	__u8	flags;
427 	__u32	hdr_len;
428 
429 	/* All offsets are in bytes relative to the end of this header */
430 	__u32	func_info_off;
431 	__u32	func_info_len;
432 	__u32	line_info_off;
433 	__u32	line_info_len;
434 
435 	/* optional part of .BTF.ext header */
436 	__u32	core_relo_off;
437 	__u32	core_relo_len;
438 };
439 
440 struct btf_ext {
441 	union {
442 		struct btf_ext_header *hdr;
443 		void *data;
444 	};
445 	struct btf_ext_info func_info;
446 	struct btf_ext_info line_info;
447 	struct btf_ext_info core_relo_info;
448 	__u32 data_size;
449 };
450 
451 struct btf_ext_info_sec {
452 	__u32	sec_name_off;
453 	__u32	num_info;
454 	/* Followed by num_info * record_size number of bytes */
455 	__u8	data[];
456 };
457 
458 /* The minimum bpf_func_info checked by the loader */
459 struct bpf_func_info_min {
460 	__u32   insn_off;
461 	__u32   type_id;
462 };
463 
464 /* The minimum bpf_line_info checked by the loader */
465 struct bpf_line_info_min {
466 	__u32	insn_off;
467 	__u32	file_name_off;
468 	__u32	line_off;
469 	__u32	line_col;
470 };
471 
472 
473 typedef int (*type_id_visit_fn)(__u32 *type_id, void *ctx);
474 typedef int (*str_off_visit_fn)(__u32 *str_off, void *ctx);
475 int btf_type_visit_type_ids(struct btf_type *t, type_id_visit_fn visit, void *ctx);
476 int btf_type_visit_str_offs(struct btf_type *t, str_off_visit_fn visit, void *ctx);
477 int btf_ext_visit_type_ids(struct btf_ext *btf_ext, type_id_visit_fn visit, void *ctx);
478 int btf_ext_visit_str_offs(struct btf_ext *btf_ext, str_off_visit_fn visit, void *ctx);
479 __s32 btf__find_by_name_kind_own(const struct btf *btf, const char *type_name,
480 				 __u32 kind);
481 
482 typedef int (*kallsyms_cb_t)(unsigned long long sym_addr, char sym_type,
483 			     const char *sym_name, void *ctx);
484 
485 int libbpf_kallsyms_parse(kallsyms_cb_t cb, void *arg);
486 
487 /* handle direct returned errors */
libbpf_err(int ret)488 static inline int libbpf_err(int ret)
489 {
490 	if (ret < 0)
491 		errno = -ret;
492 	return ret;
493 }
494 
495 /* handle errno-based (e.g., syscall or libc) errors according to libbpf's
496  * strict mode settings
497  */
libbpf_err_errno(int ret)498 static inline int libbpf_err_errno(int ret)
499 {
500 	/* errno is already assumed to be set on error */
501 	return ret < 0 ? -errno : ret;
502 }
503 
504 /* handle error for pointer-returning APIs, err is assumed to be < 0 always */
libbpf_err_ptr(int err)505 static inline void *libbpf_err_ptr(int err)
506 {
507 	/* set errno on error, this doesn't break anything */
508 	errno = -err;
509 	return NULL;
510 }
511 
512 /* handle pointer-returning APIs' error handling */
libbpf_ptr(void * ret)513 static inline void *libbpf_ptr(void *ret)
514 {
515 	/* set errno on error, this doesn't break anything */
516 	if (IS_ERR(ret))
517 		errno = -PTR_ERR(ret);
518 
519 	return IS_ERR(ret) ? NULL : ret;
520 }
521 
str_is_empty(const char * s)522 static inline bool str_is_empty(const char *s)
523 {
524 	return !s || !s[0];
525 }
526 
is_ldimm64_insn(struct bpf_insn * insn)527 static inline bool is_ldimm64_insn(struct bpf_insn *insn)
528 {
529 	return insn->code == (BPF_LD | BPF_IMM | BPF_DW);
530 }
531 
532 /* if fd is stdin, stdout, or stderr, dup to a fd greater than 2
533  * Takes ownership of the fd passed in, and closes it if calling
534  * fcntl(fd, F_DUPFD_CLOEXEC, 3).
535  */
ensure_good_fd(int fd)536 static inline int ensure_good_fd(int fd)
537 {
538 	int old_fd = fd, saved_errno;
539 
540 	if (fd < 0)
541 		return fd;
542 	if (fd < 3) {
543 		fd = fcntl(fd, F_DUPFD_CLOEXEC, 3);
544 		saved_errno = errno;
545 		close(old_fd);
546 		if (fd < 0) {
547 			pr_warn("failed to dup FD %d to FD > 2: %d\n", old_fd, -saved_errno);
548 			errno = saved_errno;
549 		}
550 	}
551 	return fd;
552 }
553 
554 /* The following two functions are exposed to bpftool */
555 int bpf_core_add_cands(struct bpf_core_cand *local_cand,
556 		       size_t local_essent_len,
557 		       const struct btf *targ_btf,
558 		       const char *targ_btf_name,
559 		       int targ_start_id,
560 		       struct bpf_core_cand_list *cands);
561 void bpf_core_free_cands(struct bpf_core_cand_list *cands);
562 
563 struct usdt_manager *usdt_manager_new(struct bpf_object *obj);
564 void usdt_manager_free(struct usdt_manager *man);
565 struct bpf_link * usdt_manager_attach_usdt(struct usdt_manager *man,
566 					   const struct bpf_program *prog,
567 					   pid_t pid, const char *path,
568 					   const char *usdt_provider, const char *usdt_name,
569 					   __u64 usdt_cookie);
570 
is_pow_of_2(size_t x)571 static inline bool is_pow_of_2(size_t x)
572 {
573 	return x && (x & (x - 1)) == 0;
574 }
575 
576 #define PROG_LOAD_ATTEMPTS 5
577 int sys_bpf_prog_load(union bpf_attr *attr, unsigned int size, int attempts);
578 
579 #endif /* __LIBBPF_LIBBPF_INTERNAL_H */
580