projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| d73a3397 WL |
1 | #ifndef _ASM_X86_QSPINLOCK_H |
| 2 | #define _ASM_X86_QSPINLOCK_H | |
| 3 | ||
| 2aa79af6 | 4 | #include <asm/cpufeature.h> |
| d73a3397 | 5 | #include <asm-generic/qspinlock_types.h> |
| f233f7f1 | 6 | #include <asm/paravirt.h> |
| d73a3397 WL |
7 | |
| 8 | #define queued_spin_unlock queued_spin_unlock | |
| 9 | /** | |
| 10 | * queued_spin_unlock - release a queued spinlock | |
| 11 | * @lock : Pointer to queued spinlock structure | |
| 12 | * | |
| 13 | * A smp_store_release() on the least-significant byte. | |
| 14 | */ | |
| f233f7f1 | 15 | static inline void native_queued_spin_unlock(struct qspinlock *lock) |
| d73a3397 WL |
16 | { |
| 17 | smp_store_release((u8 *)lock, 0); | |
| 18 | } | |
| 19 | ||
| f233f7f1 PZI |
20 | #ifdef CONFIG_PARAVIRT_SPINLOCKS |
| 21 | extern void native_queued_spin_lock_slowpath(struct qspinlock *lock, u32 val); | |
| 22 | extern void __pv_init_lock_hash(void); | |
| 23 | extern void __pv_queued_spin_lock_slowpath(struct qspinlock *lock, u32 val); | |
| 24 | extern void __raw_callee_save___pv_queued_spin_unlock(struct qspinlock *lock); | |
| 25 | ||
| 26 | static inline void queued_spin_lock_slowpath(struct qspinlock *lock, u32 val) | |
| 27 | { | |
| 28 | pv_queued_spin_lock_slowpath(lock, val); | |
| 29 | } | |
| 30 | ||
| 31 | static inline void queued_spin_unlock(struct qspinlock *lock) | |
| 32 | { | |
| 33 | pv_queued_spin_unlock(lock); | |
| 34 | } | |
| 35 | #else | |
| 36 | static inline void queued_spin_unlock(struct qspinlock *lock) | |
| 37 | { | |
| 38 | native_queued_spin_unlock(lock); | |
| 39 | } | |
| 40 | #endif | |
| 41 | ||
| a6b27785 | 42 | #ifdef CONFIG_PARAVIRT |
| 43b3f028 | 43 | #define virt_spin_lock virt_spin_lock |
| 43b3f028 | 44 | static inline bool virt_spin_lock(struct qspinlock *lock) |
| 2aa79af6 PZI |
45 | { |
| 46 | if (!static_cpu_has(X86_FEATURE_HYPERVISOR)) | |
| 47 | return false; | |
| 48 | ||
| 43b3f028 PZ |
49 | /* |
| 50 | * On hypervisors without PARAVIRT_SPINLOCKS support we fall | |
| 51 | * back to a Test-and-Set spinlock, because fair locks have | |
| 52 | * horrible lock 'holder' preemption issues. | |
| 53 | */ | |
| 54 | ||
| 55 | do { | |
| 56 | while (atomic_read(&lock->val) != 0) | |
| 57 | cpu_relax(); | |
| 58 | } while (atomic_cmpxchg(&lock->val, 0, _Q_LOCKED_VAL) != 0); | |
| 2aa79af6 PZI |
59 | |
| 60 | return true; | |
| 61 | } | |
| a6b27785 | 62 | #endif /* CONFIG_PARAVIRT */ |
| 2aa79af6 | 63 | |
| d73a3397 WL |
64 | #include <asm-generic/qspinlock.h> |
| 65 | ||
| 66 | #endif /* _ASM_X86_QSPINLOCK_H */ |