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

File Facts

System

Linux kernel

Corpus path

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

Extension

.c

Size

3789 bytes

Lines

250

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

• No C-style include directives detected by the generator.

Detected Declarations

• struct padded_implicitly
• struct padded_explicitly
• struct padded_a_lot
• struct padded_cache_line
• struct zone_padding
• struct zone
• struct padding_wo_named_members
• struct padding_weird_1
• struct padding_weird_2
• struct exact_1byte
• struct padded_1byte
• struct exact_2bytes
• struct padded_2bytes
• struct exact_4bytes
• struct padded_4bytes
• struct exact_8bytes
• struct padded_8bytes
• struct ff_periodic_effect
• struct ib_wc
• struct acpi_object_method
• struct nested_unpacked
• struct nested_packed
• struct outer_mixed_but_unpacked

Annotated Snippet

struct padded_implicitly {
	int a;
	long b;
	char c;
};

/* ------ END-EXPECTED-OUTPUT ------ */

/* ----- START-EXPECTED-OUTPUT ----- */
/*
 *struct padded_explicitly {
 *	int a;
 *	long: 0;
 *	int b;
 *};
 *
 */
/* ------ END-EXPECTED-OUTPUT ------ */

struct padded_explicitly {
	int a;
	int: 1; /* algo will emit aligning `long: 0;` here */
	int b;
};

/* ----- START-EXPECTED-OUTPUT ----- */
struct padded_a_lot {
	int a;
	long: 64;
	long: 64;
	int b;
};

/* ------ END-EXPECTED-OUTPUT ------ */

/* ----- START-EXPECTED-OUTPUT ----- */
/*
 *struct padded_cache_line {
 *	int a;
 *	long: 64;
 *	long: 64;
 *	long: 64;
 *	int b;
 *	long: 64;
 *	long: 64;
 *	long: 64;
 *};
 *
 */
/* ------ END-EXPECTED-OUTPUT ------ */

struct padded_cache_line {
	int a;
	int b __attribute__((aligned(32)));
};

/* ----- START-EXPECTED-OUTPUT ----- */
/*
 *struct zone_padding {
 *	char x[0];
 *};
 *
 *struct zone {
 *	int a;
 *	short b;
 *	long: 0;
 *	struct zone_padding __pad__;
 *};
 *
 */
/* ------ END-EXPECTED-OUTPUT ------ */

struct zone_padding {
	char x[0];
} __attribute__((__aligned__(8)));

struct zone {
	int a;
	short b;
	struct zone_padding __pad__;
};

/* ----- START-EXPECTED-OUTPUT ----- */
struct padding_wo_named_members {
	long: 64;
	long: 64;
};

struct padding_weird_1 {
	int a;

Annotation

• Detected declarations: `struct padded_implicitly`, `struct padded_explicitly`, `struct padded_a_lot`, `struct padded_cache_line`, `struct zone_padding`, `struct zone`, `struct padding_wo_named_members`, `struct padding_weird_1`, `struct padding_weird_2`, `struct exact_1byte`.
• 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.