diff options
Diffstat (limited to 'arch/x86/include/asm/qspinlock.h')
| -rw-r--r-- | arch/x86/include/asm/qspinlock.h | 57 | 
1 files changed, 57 insertions, 0 deletions
diff --git a/arch/x86/include/asm/qspinlock.h b/arch/x86/include/asm/qspinlock.h new file mode 100644 index 000000000000..9d51fae1cba3 --- /dev/null +++ b/arch/x86/include/asm/qspinlock.h @@ -0,0 +1,57 @@ +#ifndef _ASM_X86_QSPINLOCK_H +#define _ASM_X86_QSPINLOCK_H + +#include <asm/cpufeature.h> +#include <asm-generic/qspinlock_types.h> +#include <asm/paravirt.h> + +#define	queued_spin_unlock queued_spin_unlock +/** + * queued_spin_unlock - release a queued spinlock + * @lock : Pointer to queued spinlock structure + * + * A smp_store_release() on the least-significant byte. + */ +static inline void native_queued_spin_unlock(struct qspinlock *lock) +{ +	smp_store_release((u8 *)lock, 0); +} + +#ifdef CONFIG_PARAVIRT_SPINLOCKS +extern void native_queued_spin_lock_slowpath(struct qspinlock *lock, u32 val); +extern void __pv_init_lock_hash(void); +extern void __pv_queued_spin_lock_slowpath(struct qspinlock *lock, u32 val); +extern void __raw_callee_save___pv_queued_spin_unlock(struct qspinlock *lock); + +static inline void queued_spin_lock_slowpath(struct qspinlock *lock, u32 val) +{ +	pv_queued_spin_lock_slowpath(lock, val); +} + +static inline void queued_spin_unlock(struct qspinlock *lock) +{ +	pv_queued_spin_unlock(lock); +} +#else +static inline void queued_spin_unlock(struct qspinlock *lock) +{ +	native_queued_spin_unlock(lock); +} +#endif + +#define virt_queued_spin_lock virt_queued_spin_lock + +static inline bool virt_queued_spin_lock(struct qspinlock *lock) +{ +	if (!static_cpu_has(X86_FEATURE_HYPERVISOR)) +		return false; + +	while (atomic_cmpxchg(&lock->val, 0, _Q_LOCKED_VAL) != 0) +		cpu_relax(); + +	return true; +} + +#include <asm-generic/qspinlock.h> + +#endif /* _ASM_X86_QSPINLOCK_H */  |