arch/arm/include/asm/mcs_spinlock.h

File Facts

System

Linux kernel

Corpus path

arch/arm/include/asm/mcs_spinlock.h

Extension

.h

Size

570 bytes

Lines

25

Domain

Architecture Layer

Bucket

arch/arm

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.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.

Dependency Surface

• asm/spinlock.h

Detected Declarations

• No top-level syscall, struct, function, initcall, or export declaration detected by the generator.

Annotated Snippet

#ifndef __ASM_MCS_LOCK_H
#define __ASM_MCS_LOCK_H

#ifdef CONFIG_SMP
#include <asm/spinlock.h>

/* MCS spin-locking. */
#define arch_mcs_spin_lock_contended(lock)				\
do {									\
	/* Ensure prior stores are observed before we enter wfe. */	\
	smp_mb();							\
	while (!(smp_load_acquire(lock)))				\
		wfe();							\
} while (0)								\

#define arch_mcs_spin_unlock_contended(lock)				\
do {									\
	smp_store_release(lock, 1);					\
	dsb_sev();							\
} while (0)

#endif	/* CONFIG_SMP */
#endif	/* __ASM_MCS_LOCK_H */

Annotation

• Immediate include surface: `asm/spinlock.h`.
• Atlas domain: Architecture Layer / arch/arm.
• Implementation status: source implementation candidate.
• Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.

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.