arch/arm64/include/asm/smp_plat.h

File Facts

System

Linux kernel

Corpus path

arch/arm64/include/asm/smp_plat.h

Extension

.h

Size

824 bytes

Lines

45

Domain

Architecture Layer

Bucket

arch/arm64

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.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/cpumask.h
• asm/smp.h
• asm/types.h

Detected Declarations

• struct mpidr_hash
• function mpidr_hash_size
• function get_logical_index

Annotated Snippet

struct mpidr_hash {
	u64	mask;
	u32	shift_aff[4];
	u32	bits;
};

extern struct mpidr_hash mpidr_hash;

static inline u32 mpidr_hash_size(void)
{
	return 1 << mpidr_hash.bits;
}

/*
 * Retrieve logical cpu index corresponding to a given MPIDR.Aff*
 *  - mpidr: MPIDR.Aff* bits to be used for the look-up
 *
 * Returns the cpu logical index or -EINVAL on look-up error
 */
static inline int get_logical_index(u64 mpidr)
{
	int cpu;
	for (cpu = 0; cpu < nr_cpu_ids; cpu++)
		if (cpu_logical_map(cpu) == mpidr)
			return cpu;
	return -EINVAL;
}

#endif /* __ASM_SMP_PLAT_H */

Annotation

• Immediate include surface: `linux/cpumask.h`, `asm/smp.h`, `asm/types.h`.
• Detected declarations: `struct mpidr_hash`, `function mpidr_hash_size`, `function get_logical_index`.
• Atlas domain: Architecture Layer / arch/arm64.
• 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.