/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _ASM_POWERPC_QSPINLOCK_H #define _ASM_POWERPC_QSPINLOCK_H #include <asm-generic/qspinlock_types.h> #include <asm/paravirt.h> #define _Q_PENDING_LOOPS (1 << 9) /* not tuned */ #ifdef CONFIG_PARAVIRT_SPINLOCKS extern void native_queued_spin_lock_slowpath(struct qspinlock *lock, u32 val); extern void __pv_queued_spin_lock_slowpath(struct qspinlock *lock, u32 val); extern void __pv_queued_spin_unlock(struct qspinlock *lock); static __always_inline void queued_spin_lock_slowpath(struct qspinlock *lock, u32 val) { if (!is_shared_processor()) native_queued_spin_lock_slowpath(lock, val); else __pv_queued_spin_lock_slowpath(lock, val); } #define queued_spin_unlock queued_spin_unlock static inline void queued_spin_unlock(struct qspinlock *lock) { if (!is_shared_processor()) smp_store_release(&lock->locked, 0); else __pv_queued_spin_unlock(lock); } #else extern void queued_spin_lock_slowpath(struct qspinlock *lock, u32 val); #endif static __always_inline void queued_spin_lock(struct qspinlock *lock) { u32 val = 0; if (likely(atomic_try_cmpxchg_lock(&lock->val, &val, _Q_LOCKED_VAL))) return; queued_spin_lock_slowpath(lock, val); } #define queued_spin_lock queued_spin_lock #ifdef CONFIG_PARAVIRT_SPINLOCKS #define SPIN_THRESHOLD (1<<15) /* not tuned */ static __always_inline void pv_wait(u8 *ptr, u8 val) { if (*ptr != val) return; yield_to_any(); /* * We could pass in a CPU here if waiting in the queue and yield to * the previous CPU in the queue. */ } static __always_inline void pv_kick(int cpu) { prod_cpu(cpu); } extern void __pv_init_lock_hash(void); static inline void pv_spinlocks_init(void) { __pv_init_lock_hash(); } #endif /* * Queued spinlocks rely heavily on smp_cond_load_relaxed() to busy-wait, * which was found to have performance problems if implemented with * the preferred spin_begin()/spin_end() SMT priority pattern. Use the * generic version instead. */ #include <asm-generic/qspinlock.h> #endif /* _ASM_POWERPC_QSPINLOCK_H */