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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_LOONGARCH_QSPINLOCK_H
#define _ASM_LOONGARCH_QSPINLOCK_H
#include <linux/jump_label.h>
#ifdef CONFIG_PARAVIRT
DECLARE_STATIC_KEY_FALSE(virt_spin_lock_key);
#define virt_spin_lock virt_spin_lock
static inline bool virt_spin_lock(struct qspinlock *lock)
{
int val;
if (!static_branch_unlikely(&virt_spin_lock_key))
return false;
/*
* On hypervisors without PARAVIRT_SPINLOCKS support we fall
* back to a Test-and-Set spinlock, because fair locks have
* horrible lock 'holder' preemption issues.
*/
__retry:
val = atomic_read(&lock->val);
if (val || !atomic_try_cmpxchg(&lock->val, &val, _Q_LOCKED_VAL)) {
cpu_relax();
goto __retry;
}
return true;
}
#endif /* CONFIG_PARAVIRT */
#include <asm-generic/qspinlock.h>
#endif // _ASM_LOONGARCH_QSPINLOCK_H
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