alistair23-linux/tools/testing/selftests/bpf/netcnt_common.h

// 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
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> 2018-09-28 08:46:00 -06:00			`// 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`