tools/testing/selftests/bpf/progs/trace_vprintk.c
Source file repositories/reference/linux-study-clean/tools/testing/selftests/bpf/progs/trace_vprintk.c
File Facts
- System
- Linux kernel
- Corpus path
tools/testing/selftests/bpf/progs/trace_vprintk.c- Extension
.c- Size
- 932 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
vmlinux.hbpf/bpf_helpers.hbpf/bpf_tracing.hbpf_misc.h
Detected Declarations
function sys_enter
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2021 Facebook */
#include "vmlinux.h"
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
#include "bpf_misc.h"
char _license[] SEC("license") = "GPL";
int null_data_vprintk_ret = 0;
int trace_vprintk_ret = 0;
int trace_vprintk_ran = 0;
SEC("fentry/" SYS_PREFIX "sys_nanosleep")
int sys_enter(void *ctx)
{
static const char one[] = "1";
static const char three[] = "3";
static const char five[] = "5";
static const char seven[] = "7";
static const char nine[] = "9";
static const char f[] = "%pS\n";
/* runner doesn't search for \t, just ensure it compiles */
bpf_printk("\t");
trace_vprintk_ret = __bpf_vprintk("%s,%d,%s,%d,%s,%d,%s,%d,%s,%d %d\n",
one, 2, three, 4, five, 6, seven, 8, nine, 10, ++trace_vprintk_ran);
/* non-NULL fmt w/ NULL data should result in error */
null_data_vprintk_ret = bpf_trace_vprintk(f, sizeof(f), NULL, 0);
return 0;
}
Annotation
- Immediate include surface: `vmlinux.h`, `bpf/bpf_helpers.h`, `bpf/bpf_tracing.h`, `bpf_misc.h`.
- Detected declarations: `function sys_enter`.
- 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.