tools/testing/selftests/net/sample_map_ret0.bpf.c

File Facts

System

Linux kernel

Corpus path

tools/testing/selftests/net/sample_map_ret0.bpf.c

Extension

.c

Size

677 bytes

Lines

35

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.

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

Dependency Surface

• linux/bpf.h
• bpf/bpf_helpers.h

Detected Declarations

• No top-level syscall, struct, function, initcall, or export declaration detected by the generator.

Annotated Snippet

#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>

struct {
	__uint(type, BPF_MAP_TYPE_HASH);
	__type(key, __u32);
	__type(value, long);
	__uint(max_entries, 2);
} htab SEC(".maps");

struct {
	__uint(type, BPF_MAP_TYPE_ARRAY);
	__type(key, __u32);
	__type(value, long);
	__uint(max_entries, 2);
} array SEC(".maps");

/* Sample program which should always load for testing control paths. */
SEC("xdp") int func()
{
	__u64 key64 = 0;
	__u32 key = 0;
	long *value;

	value = bpf_map_lookup_elem(&htab, &key);
	if (!value)
		return 1;
	value = bpf_map_lookup_elem(&array, &key64);
	if (!value)
		return 1;

	return 0;
}

Annotation

• Immediate include surface: `linux/bpf.h`, `bpf/bpf_helpers.h`.
• Atlas domain: Support Tooling And Documentation / tools.
• 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.