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

File Facts

System

Linux kernel

Corpus path

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

Extension

.c

Size

775 bytes

Lines

36

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.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/bpf.h
• bpf/bpf_helpers.h

Detected Declarations

• struct htab_val
• struct htab_val_large

Annotated Snippet

struct htab_val {
	struct bpf_spin_lock lock;
	unsigned int data;
};

struct {
	__uint(type, BPF_MAP_TYPE_HASH);
	__uint(max_entries, 64);
	__type(key, unsigned int);
	__type(value, struct htab_val);
	__uint(map_flags, BPF_F_NO_PREALLOC);
} htab SEC(".maps");

#define HTAB_NDATA 256

struct htab_val_large {
	struct bpf_spin_lock lock;
	__u32 seq;
	__u64 data[HTAB_NDATA];
};

struct {
	__uint(type, BPF_MAP_TYPE_HASH);
	__uint(max_entries, 8);
	__type(key, unsigned int);
	__type(value, struct htab_val_large);
	__uint(map_flags, BPF_F_NO_PREALLOC);
} htab_lock_consistency SEC(".maps");

Annotation

• Immediate include surface: `linux/bpf.h`, `bpf/bpf_helpers.h`.
• Detected declarations: `struct htab_val`, `struct htab_val_large`.
• Atlas domain: Support Tooling And Documentation / tools.
• Implementation status: source implementation candidate.
• Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.

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.