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 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 #endif /* __BPF_UTIL__ */ 48
