/* 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 <linux/ptrace.h> #include <uapi/linux/bpf.h> #include <linux/version.h> #include <bpf/bpf_helpers.h> #include <uapi/linux/utsname.h> #include "trace_common.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("kprobe/" SYSCALL(sys_sync)) int bpf_prog1(struct pt_regs *ctx) { 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;