alistair23-linux/tools/testing/selftests/bpf/bpf_util.h
David S. Miller bc1bafbbe9 bpf: Move endianness BPF helpers out of bpf_util.h
We do not want to include things like stdio.h and friends into
eBPF program builds.  bpf_util.h is for host compiled programs,
so eBPF C-code helpers don't really belong there.

Add a new bpf_endian.h as a quick fix for this for now.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-01 12:43:49 -07:00

46 lines
982 B
C

#ifndef __BPF_UTIL__
#define __BPF_UTIL__
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
static inline unsigned int bpf_num_possible_cpus(void)
{
static const char *fcpu = "/sys/devices/system/cpu/possible";
unsigned int start, end, possible_cpus = 0;
char buff[128];
FILE *fp;
fp = fopen(fcpu, "r");
if (!fp) {
printf("Failed to open %s: '%s'!\n", fcpu, strerror(errno));
exit(1);
}
while (fgets(buff, sizeof(buff), fp)) {
if (sscanf(buff, "%u-%u", &start, &end) == 2) {
possible_cpus = start == 0 ? end + 1 : 0;
break;
}
}
fclose(fp);
if (!possible_cpus) {
printf("Failed to retrieve # possible CPUs!\n");
exit(1);
}
return possible_cpus;
}
#define __bpf_percpu_val_align __attribute__((__aligned__(8)))
#define BPF_DECLARE_PERCPU(type, name) \
struct { type v; /* padding */ } __bpf_percpu_val_align \
name[bpf_num_possible_cpus()]
#define bpf_percpu(name, cpu) name[(cpu)].v
#endif /* __BPF_UTIL__ */