44 строки
1.1 KiB
C
44 строки
1.1 KiB
C
/* Copyright (c) 2016 Sargun Dhillon <sargun@sargun.me>
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of version 2 of the GNU General Public
|
|
* License as published by the Free Software Foundation.
|
|
*/
|
|
|
|
#include "vmlinux.h"
|
|
#include <linux/version.h>
|
|
#include <bpf/bpf_helpers.h>
|
|
#include <bpf/bpf_tracing.h>
|
|
#include <bpf/bpf_core_read.h>
|
|
|
|
struct {
|
|
__uint(type, BPF_MAP_TYPE_CGROUP_ARRAY);
|
|
__uint(key_size, sizeof(u32));
|
|
__uint(value_size, sizeof(u32));
|
|
__uint(max_entries, 1);
|
|
} cgroup_map SEC(".maps");
|
|
|
|
struct {
|
|
__uint(type, BPF_MAP_TYPE_ARRAY);
|
|
__type(key, u32);
|
|
__type(value, u64);
|
|
__uint(max_entries, 1);
|
|
} perf_map SEC(".maps");
|
|
|
|
/* Writes the last PID that called sync to a map at index 0 */
|
|
SEC("ksyscall/sync")
|
|
int BPF_KSYSCALL(bpf_prog1)
|
|
{
|
|
u64 pid = bpf_get_current_pid_tgid();
|
|
int idx = 0;
|
|
|
|
if (!bpf_current_task_under_cgroup(&cgroup_map, 0))
|
|
return 0;
|
|
|
|
bpf_map_update_elem(&perf_map, &idx, &pid, BPF_ANY);
|
|
return 0;
|
|
}
|
|
|
|
char _license[] SEC("license") = "GPL";
|
|
u32 _version SEC("version") = LINUX_VERSION_CODE;
|