linux_dsm_epyc7002/tools/testing/selftests/bpf/progs/loop4.c
Alexei Starovoitov a78d0dbec7 selftests/bpf: add loop test 4
Add a test that returns a 'random' number between [0, 2^20)
If state pruning is not working correctly for loop body the number of
processed insns will be 2^20 * num_of_insns_in_loop_body and the program
will be rejected.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
2019-08-06 08:20:25 -07:00

19 lines
332 B
C

// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2019 Facebook
#include <linux/bpf.h>
#include "bpf_helpers.h"
char _license[] SEC("license") = "GPL";
SEC("socket")
int combinations(volatile struct __sk_buff* skb)
{
int ret = 0, i;
#pragma nounroll
for (i = 0; i < 20; i++)
if (skb->len)
ret |= 1 << i;
return ret;
}