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

File Facts

System

Linux kernel

Corpus path

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

Extension

.c

Size

841 bytes

Lines

39

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

• function BPF_PROG
• function BPF_PROG

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2020 Facebook
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>

struct {
	__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
	__uint(max_entries, 1);
	__type(key, int);
	__type(value, int);
} array_1 SEC(".maps");

struct {
	__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
	__uint(max_entries, 1);
	__type(key, int);
	__type(value, int);
	__uint(map_flags, BPF_F_PRESERVE_ELEMS);
} array_2 SEC(".maps");

SEC("raw_tp/sched_switch")
int BPF_PROG(read_array_1)
{
	struct bpf_perf_event_value val;

	return bpf_perf_event_read_value(&array_1, 0, &val, sizeof(val));
}

SEC("raw_tp/task_rename")
int BPF_PROG(read_array_2)
{
	struct bpf_perf_event_value val;

	return bpf_perf_event_read_value(&array_2, 0, &val, sizeof(val));
}

char LICENSE[] SEC("license") = "GPL";

Annotation

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