main.bpf.c

//+build ignore
#include "vmlinux.h"
#include <bpf/bpf_helpers.h>  

#ifdef asm_inline
#undef asm_inline
#define asm_inline asm
#endif


struct {
	__uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
	__uint(max_entries, 1);
	__type(key, __u32);
	__type(value, __u64);
} percpu_hash SEC(".maps");

SEC("fentry/__x64_sys_mmap")
int mmap_fentry(struct pt_regs *ctx)
{
    __u32 key = 0;
    __u8 *value = bpf_map_lookup_elem(&percpu_hash, &key);
    if (value) {
        *value += 1;
        bpf_printk("%d",*value);
        return 0;
    }

    bpf_printk("nothing");

    return 0;
}
char LICENSE[] SEC("license") = "GPL";