diff options
Diffstat (limited to 'samples/bpf/test_current_task_under_cgroup.bpf.c')
-rw-r--r-- | samples/bpf/test_current_task_under_cgroup.bpf.c | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/samples/bpf/test_current_task_under_cgroup.bpf.c b/samples/bpf/test_current_task_under_cgroup.bpf.c new file mode 100644 index 0000000000..58b9cf7ed6 --- /dev/null +++ b/samples/bpf/test_current_task_under_cgroup.bpf.c @@ -0,0 +1,43 @@ +/* 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; |