arch/sh/include/asm/cmpxchg-cas.h

File Facts

System

Linux kernel

Corpus path

arch/sh/include/asm/cmpxchg-cas.h

Extension

.h

Size

549 bytes

Lines

26

Domain

Architecture Layer

Bucket

arch/sh

Inferred role

Architecture Layer: implementation source

Status

source 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.

Dependency Surface

• asm/cmpxchg-xchg.h

Detected Declarations

• function __cmpxchg_u32
• function xchg_u32

Annotated Snippet

#ifndef __ASM_SH_CMPXCHG_CAS_H
#define __ASM_SH_CMPXCHG_CAS_H

static inline unsigned long
__cmpxchg_u32(volatile u32 *m, unsigned long old, unsigned long new)
{
	__asm__ __volatile__("cas.l %1,%0,@r0"
		: "+r"(new)
		: "r"(old), "z"(m)
		: "t", "memory" );
	return new;
}

static inline unsigned long xchg_u32(volatile u32 *m, unsigned long val)
{
	unsigned long old;
	do old = *m;
	while (__cmpxchg_u32(m, old, val) != old);
	return old;
}

#include <asm/cmpxchg-xchg.h>

#endif /* __ASM_SH_CMPXCHG_CAS_H */

Annotation

• Immediate include surface: `asm/cmpxchg-xchg.h`.
• Detected declarations: `function __cmpxchg_u32`, `function xchg_u32`.
• Atlas domain: Architecture Layer / arch/sh.
• 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.