linux/include/linux/bit_spinlock.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __LINUX_BIT_SPINLOCK_H
#define __LINUX_BIT_SPINLOCK_H

#include <linux/kernel.h>
#include <linux/preempt.h>
#include <linux/atomic.h>
#include <linux/bug.h>

/*
 *  bit-based spin_lock()
 *
 * Don't use this unless you really need to: spin_lock() and spin_unlock()
 * are significantly faster.
 */
static inline void bit_spin_lock(int bitnum, unsigned long *addr)
{ … }

/*
 * Return true if it was acquired
 */
static inline int bit_spin_trylock(int bitnum, unsigned long *addr)
{ … }

/*
 *  bit-based spin_unlock()
 */
static inline void bit_spin_unlock(int bitnum, unsigned long *addr)
{ … }

/*
 *  bit-based spin_unlock()
 *  non-atomic version, which can be used eg. if the bit lock itself is
 *  protecting the rest of the flags in the word.
 */
static inline void __bit_spin_unlock(int bitnum, unsigned long *addr)
{ … }

/*
 * Return true if the lock is held.
 */
static inline int bit_spin_is_locked(int bitnum, unsigned long *addr)
{ … }

#endif /* __LINUX_BIT_SPINLOCK_H */