arch/riscv/include/asm/spinlock.h

Source file repositories/reference/linux-study-clean/arch/riscv/include/asm/spinlock.h

File Facts

System
Linux kernel
Corpus path
arch/riscv/include/asm/spinlock.h
Extension
.h
Size
1302 bytes
Lines
51
Domain
Architecture Layer
Bucket
arch/riscv
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.

Dependency Surface

Detected Declarations

Annotated Snippet

#ifndef __ASM_RISCV_SPINLOCK_H
#define __ASM_RISCV_SPINLOCK_H

#ifdef CONFIG_QUEUED_SPINLOCKS
#define _Q_PENDING_LOOPS	(1 << 9)
#endif

#ifdef CONFIG_RISCV_COMBO_SPINLOCKS

#define __no_arch_spinlock_redefine
#include <asm/ticket_spinlock.h>
#include <asm/qspinlock.h>
#include <asm/jump_label.h>

/*
 * TODO: Use an alternative instead of a static key when we are able to parse
 * the extensions string earlier in the boot process.
 */
DECLARE_STATIC_KEY_TRUE(qspinlock_key);

#define SPINLOCK_BASE_DECLARE(op, type, type_lock)			\
static __always_inline type arch_spin_##op(type_lock lock)		\
{									\
	if (static_branch_unlikely(&qspinlock_key))			\
		return queued_spin_##op(lock);				\
	return ticket_spin_##op(lock);					\
}

SPINLOCK_BASE_DECLARE(lock, void, arch_spinlock_t *)
SPINLOCK_BASE_DECLARE(unlock, void, arch_spinlock_t *)
SPINLOCK_BASE_DECLARE(is_locked, int, arch_spinlock_t *)
SPINLOCK_BASE_DECLARE(is_contended, int, arch_spinlock_t *)
SPINLOCK_BASE_DECLARE(trylock, bool, arch_spinlock_t *)
SPINLOCK_BASE_DECLARE(value_unlocked, int, arch_spinlock_t)

#elif defined(CONFIG_RISCV_QUEUED_SPINLOCKS)

#include <asm/qspinlock.h>

#else

#include <asm/ticket_spinlock.h>

#endif

#include <asm/qrwlock.h>

#endif /* __ASM_RISCV_SPINLOCK_H */

Annotation

Implementation Notes