arch/x86/lib/cpu.c
Source file repositories/reference/linux-study-clean/arch/x86/lib/cpu.c
File Facts
- System
- Linux kernel
- Corpus path
arch/x86/lib/cpu.c- Extension
.c- Size
- 624 bytes
- Lines
- 39
- Domain
- Architecture Layer
- Bucket
- arch/x86
- Inferred role
- Architecture Layer: exported/initcall integration point
- Status
- integration implementation candidate
Why This File Exists
CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.
- CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.
- Exports symbols or registers init work; inspect boot/module ordering and who consumes the exported contract.
Dependency Surface
linux/types.hlinux/export.hasm/cpu.h
Detected Declarations
function x86_familyfunction x86_modelfunction x86_steppingexport x86_familyexport x86_modelexport x86_stepping
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0-only
#include <linux/types.h>
#include <linux/export.h>
#include <asm/cpu.h>
unsigned int x86_family(unsigned int sig)
{
unsigned int x86;
x86 = (sig >> 8) & 0xf;
if (x86 == 0xf)
x86 += (sig >> 20) & 0xff;
return x86;
}
EXPORT_SYMBOL_GPL(x86_family);
unsigned int x86_model(unsigned int sig)
{
unsigned int fam, model;
fam = x86_family(sig);
model = (sig >> 4) & 0xf;
if (fam >= 0x6)
model += ((sig >> 16) & 0xf) << 4;
return model;
}
EXPORT_SYMBOL_GPL(x86_model);
unsigned int x86_stepping(unsigned int sig)
{
return sig & 0xf;
}
EXPORT_SYMBOL_GPL(x86_stepping);
Annotation
- Immediate include surface: `linux/types.h`, `linux/export.h`, `asm/cpu.h`.
- Detected declarations: `function x86_family`, `function x86_model`, `function x86_stepping`, `export x86_family`, `export x86_model`, `export x86_stepping`.
- Atlas domain: Architecture Layer / arch/x86.
- Implementation status: integration 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.