kernel_optimize_test/samples/bpf/test_overhead_kprobe_kern.c
Ilya Leoshkevich e4d9c23207 samples/bpf, selftests/bpf: Use bpf_probe_read_kernel
A handful of samples and selftests fail to build on s390, because
after commit 0ebeea8ca8 ("bpf: Restrict bpf_probe_read{, str}()
only to archs where they work") bpf_probe_read is not available
anymore.

Fix by using bpf_probe_read_kernel.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200720114806.88823-1-iii@linux.ibm.com
2020-07-21 13:26:26 -07:00

49 lines
1.3 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/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
#define _(P) \
({ \
typeof(P) val = 0; \
bpf_probe_read_kernel(&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_kernel(oldcomm, sizeof(oldcomm), &tsk->comm);
bpf_probe_read_kernel(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;