tools/testing/selftests/bpf/progs/udp_limit.c

Source file repositories/reference/linux-study-clean/tools/testing/selftests/bpf/progs/udp_limit.c

File Facts

System
Linux kernel
Corpus path
tools/testing/selftests/bpf/progs/udp_limit.c
Extension
.c
Size
1139 bytes
Lines
60
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: implementation source
Status
source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

SEC("cgroup/sock_create")
int sock(struct bpf_sock *ctx)
{
	int *sk_storage;

	if (ctx->type != SOCK_DGRAM)
		return 1;

	sk_storage = bpf_sk_storage_get(&sk_map, ctx, 0,
					BPF_SK_STORAGE_GET_F_CREATE);
	if (!sk_storage)
		return 0;
	*sk_storage = 0xdeadbeef;

	__sync_fetch_and_add(&invocations, 1);

	if (in_use > 0) {
		/* BPF_CGROUP_INET_SOCK_RELEASE is _not_ called
		 * when we return an error from the BPF
		 * program!
		 */
		return 0;
	}

	__sync_fetch_and_add(&in_use, 1);
	return 1;
}

SEC("cgroup/sock_release")
int sock_release(struct bpf_sock *ctx)
{
	int *sk_storage;

	if (ctx->type != SOCK_DGRAM)
		return 1;

	sk_storage = bpf_sk_storage_get(&sk_map, ctx, 0, 0);
	if (!sk_storage || *sk_storage != 0xdeadbeef)
		return 0;

	__sync_fetch_and_add(&invocations, 1);
	__sync_fetch_and_add(&in_use, -1);
	return 1;
}

Annotation

Implementation Notes