samples/bpf/tcp_cong_kern.c

File Facts

System

Linux kernel

Corpus path

samples/bpf/tcp_cong_kern.c

Extension

.c

Size

1961 bytes

Lines

79

Domain

Support Tooling And Documentation

Bucket

samples

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.

• Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• uapi/linux/bpf.h
• uapi/linux/tcp.h
• uapi/linux/if_ether.h
• uapi/linux/if_packet.h
• uapi/linux/ip.h
• linux/socket.h
• bpf/bpf_helpers.h
• bpf/bpf_endian.h

Detected Declarations

• function datacenter

Annotated Snippet

switch (op) {
		case BPF_SOCK_OPS_NEEDS_ECN:
			rv = 1;
			break;
		case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB:
			rv = bpf_setsockopt(skops, SOL_TCP, TCP_CONGESTION,
					    cong, sizeof(cong));
			break;
		case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB:
			rv = bpf_setsockopt(skops, SOL_TCP, TCP_CONGESTION,
					    cong, sizeof(cong));
			break;
		default:
			rv = -1;
		}
	} else {
		rv = -1;
	}
#ifdef DEBUG
	bpf_printk("Returning %d\n", rv);
#endif
	skops->reply = rv;
	return 1;
}
char _license[] SEC("license") = "GPL";

Annotation

• Immediate include surface: `uapi/linux/bpf.h`, `uapi/linux/tcp.h`, `uapi/linux/if_ether.h`, `uapi/linux/if_packet.h`, `uapi/linux/ip.h`, `linux/socket.h`, `bpf/bpf_helpers.h`, `bpf/bpf_endian.h`.
• Detected declarations: `function datacenter`.
• Atlas domain: Support Tooling And Documentation / samples.
• Implementation status: source implementation candidate.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.