linux/samples/bpf/test_overhead_kprobe_kern.c
Andrii Nakryiko 3ac4dbe3dd selftests/bpf: Split off tracing-only helpers into bpf_tracing.h
Split-off PT_REGS-related helpers into bpf_tracing.h header. Adjust
selftests and samples to include it where necessary.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191008175942.1769476-5-andriin@fb.com
2019-10-08 23:16:03 +02:00

43 lines
1.0 KiB
C

/* Copyright (c) 2016 Facebook
*
* 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/version.h>
#include <linux/ptrace.h>
#include <uapi/linux/bpf.h>
#include "bpf_helpers.h"
#include "bpf_tracing.h"
#define _(P) ({typeof(P) val = 0; bpf_probe_read(&val, sizeof(val), &P); val;})
SEC("kprobe/__set_task_comm")
int prog(struct pt_regs *ctx)
{
struct signal_struct *signal;
struct task_struct *tsk;
char oldcomm[16] = {};
char newcomm[16] = {};
u16 oom_score_adj;
u32 pid;
tsk = (void *)PT_REGS_PARM1(ctx);
pid = _(tsk->pid);
bpf_probe_read(oldcomm, sizeof(oldcomm), &tsk->comm);
bpf_probe_read(newcomm, sizeof(newcomm), (void *)PT_REGS_PARM2(ctx));
signal = _(tsk->signal);
oom_score_adj = _(signal->oom_score_adj);
return 0;
}
SEC("kprobe/urandom_read")
int prog2(struct pt_regs *ctx)
{
return 0;
}
char _license[] SEC("license") = "GPL";
u32 _version SEC("version") = LINUX_VERSION_CODE;