linux_dsm_epyc7002/tools/testing/selftests/bpf/netcnt_common.h
Roman Gushchin 371e4fcc9d selftests/bpf: cgroup local storage-based network counters
This commit adds a bpf kselftest, which demonstrates how percpu
and shared cgroup local storage can be used for efficient lookup-free
network accounting.

Cgroup local storage provides generic memory area with a very efficient
lookup free access. To avoid expensive atomic operations for each
packet, per-cpu cgroup local storage is used. Each packet is initially
charged to a per-cpu counter, and only if the counter reaches certain
value (32 in this case), the charge is moved into the global atomic
counter. This allows to amortize atomic operations, keeping reasonable
accuracy.

The test also implements a naive network traffic throttling, mostly to
demonstrate the possibility of bpf cgroup--based network bandwidth
control.

Expected output:
  ./test_netcnt
  test_netcnt:PASS

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-01 16:18:33 +02:00

25 lines
320 B
C

// SPDX-License-Identifier: GPL-2.0
#ifndef __NETCNT_COMMON_H
#define __NETCNT_COMMON_H
#include <linux/types.h>
#define MAX_PERCPU_PACKETS 32
struct percpu_net_cnt {
__u64 packets;
__u64 bytes;
__u64 prev_ts;
__u64 prev_packets;
__u64 prev_bytes;
};
struct net_cnt {
__u64 packets;
__u64 bytes;
};
#endif