tools/testing/selftests/bpf/progs/fexit_bpf2bpf_simple.c

File Facts

System

Linux kernel

Corpus path

tools/testing/selftests/bpf/progs/fexit_bpf2bpf_simple.c

Extension

.c

Size

488 bytes

Lines

28

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.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/bpf.h
• bpf/bpf_helpers.h
• bpf/bpf_tracing.h

Detected Declarations

• struct sk_buff
• function BPF_PROG

Annotated Snippet

struct sk_buff {
	unsigned int len;
};

__u64 test_result = 0;

SEC("fexit/test_pkt_md_access")
int BPF_PROG(test_main2, struct sk_buff *skb, int ret)
{
	int len;

	__builtin_preserve_access_index(({
		len = skb->len;
	}));
	if (len != 74 || ret != 0)
		return 0;

	test_result = 1;
	return 0;
}
char _license[] SEC("license") = "GPL";

Annotation

• Immediate include surface: `linux/bpf.h`, `bpf/bpf_helpers.h`, `bpf/bpf_tracing.h`.
• Detected declarations: `struct sk_buff`, `function BPF_PROG`.
• 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.