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1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __BPF_UTIL__
3#define __BPF_UTIL__
4
5#include <stdio.h>
6#include <stdlib.h>
7#include <string.h>
8#include <errno.h>
9#include <bpf/libbpf.h> /* libbpf_num_possible_cpus */
10
11static inline unsigned int bpf_num_possible_cpus(void)
12{
13 int possible_cpus = libbpf_num_possible_cpus();
14
15 if (possible_cpus < 0) {
16 printf("Failed to get # of possible cpus: '%s'!\n",
17 strerror(-possible_cpus));
18 exit(1);
19 }
20 return possible_cpus;
21}
22
23/* Copy up to sz - 1 bytes from zero-terminated src string and ensure that dst
24 * is zero-terminated string no matter what (unless sz == 0, in which case
25 * it's a no-op). It's conceptually close to FreeBSD's strlcpy(), but differs
26 * in what is returned. Given this is internal helper, it's trivial to extend
27 * this, when necessary. Use this instead of strncpy inside libbpf source code.
28 */
29static inline void bpf_strlcpy(char *dst, const char *src, size_t sz)
30{
31 size_t i;
32
33 if (sz == 0)
34 return;
35
36 sz--;
37 for (i = 0; i < sz && src[i]; i++)
38 dst[i] = src[i];
39 dst[i] = '\0';
40}
41
42#define __bpf_percpu_val_align __attribute__((__aligned__(8)))
43
44#define BPF_DECLARE_PERCPU(type, name) \
45 struct { type v; /* padding */ } __bpf_percpu_val_align \
46 name[bpf_num_possible_cpus()]
47#define bpf_percpu(name, cpu) name[(cpu)].v
48
49#ifndef ARRAY_SIZE
50# define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
51#endif
52
53#ifndef sizeof_field
54#define sizeof_field(TYPE, MEMBER) sizeof((((TYPE *)0)->MEMBER))
55#endif
56
57#ifndef offsetofend
58#define offsetofend(TYPE, MEMBER) \
59 (offsetof(TYPE, MEMBER) + sizeof_field(TYPE, MEMBER))
60#endif
61
62#endif /* __BPF_UTIL__ */
1#ifndef __BPF_UTIL__
2#define __BPF_UTIL__
3
4#include <stdio.h>
5#include <stdlib.h>
6#include <string.h>
7#include <errno.h>
8
9static inline unsigned int bpf_num_possible_cpus(void)
10{
11 static const char *fcpu = "/sys/devices/system/cpu/possible";
12 unsigned int start, end, possible_cpus = 0;
13 char buff[128];
14 FILE *fp;
15
16 fp = fopen(fcpu, "r");
17 if (!fp) {
18 printf("Failed to open %s: '%s'!\n", fcpu, strerror(errno));
19 exit(1);
20 }
21
22 while (fgets(buff, sizeof(buff), fp)) {
23 if (sscanf(buff, "%u-%u", &start, &end) == 2) {
24 possible_cpus = start == 0 ? end + 1 : 0;
25 break;
26 }
27 }
28
29 fclose(fp);
30 if (!possible_cpus) {
31 printf("Failed to retrieve # possible CPUs!\n");
32 exit(1);
33 }
34
35 return possible_cpus;
36}
37
38#endif /* __BPF_UTIL__ */