JustOS/linux-6.13/tools/testing/selftests/bpf/progs/csum_diff_test.c
justuser 02e73b8cd9 up
2025-01-24 17:00:19 +03:00

43 lines
1.2 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* Copyright Amazon.com Inc. or its affiliates */
#include <linux/types.h>
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
#define BUFF_SZ 512
/* Will be updated by benchmark before program loading */
char to_buff[BUFF_SZ];
const volatile unsigned int to_buff_len = 0;
char from_buff[BUFF_SZ];
const volatile unsigned int from_buff_len = 0;
unsigned short seed = 0;
short result;
char _license[] SEC("license") = "GPL";
SEC("tc")
int compute_checksum(void *ctx)
{
int to_len_half = to_buff_len / 2;
int from_len_half = from_buff_len / 2;
short result2;
/* Calculate checksum in one go */
result2 = bpf_csum_diff((void *)from_buff, from_buff_len,
(void *)to_buff, to_buff_len, seed);
/* Calculate checksum by concatenating bpf_csum_diff()*/
result = bpf_csum_diff((void *)from_buff, from_buff_len - from_len_half,
(void *)to_buff, to_buff_len - to_len_half, seed);
result = bpf_csum_diff((void *)from_buff + (from_buff_len - from_len_half), from_len_half,
(void *)to_buff + (to_buff_len - to_len_half), to_len_half, result);
result = (result == result2) ? result : 0;
return 0;
}