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
bpf_num_possible_cpus(void)10 static inline unsigned int bpf_num_possible_cpus(void)
11 {
12 static const char *fcpu = "/sys/devices/system/cpu/possible";
13 unsigned int start, end, possible_cpus = 0;
14 char buff[128];
15 FILE *fp;
16 int n;
17
18 fp = fopen(fcpu, "r");
19 if (!fp) {
20 printf("Failed to open %s: '%s'!\n", fcpu, strerror(errno));
21 exit(1);
22 }
23
24 while (fgets(buff, sizeof(buff), fp)) {
25 n = sscanf(buff, "%u-%u", &start, &end);
26 if (n == 0) {
27 printf("Failed to retrieve # possible CPUs!\n");
28 exit(1);
29 } else if (n == 1) {
30 end = start;
31 }
32 possible_cpus = start == 0 ? end + 1 : 0;
33 break;
34 }
35 fclose(fp);
36
37 return possible_cpus;
38 }
39
40 #define __bpf_percpu_val_align __attribute__((__aligned__(8)))
41
42 #define BPF_DECLARE_PERCPU(type, name) \
43 struct { type v; /* padding */ } __bpf_percpu_val_align \
44 name[bpf_num_possible_cpus()]
45 #define bpf_percpu(name, cpu) name[(cpu)].v
46
47 #ifndef ARRAY_SIZE
48 # define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
49 #endif
50
51 #endif /* __BPF_UTIL__ */
52