From 871480933a1c28f8a9fed4c4d34d06c439a7a422 Mon Sep 17 00:00:00 2001 From: Srikant Patnaik Date: Sun, 11 Jan 2015 12:28:04 +0530 Subject: Moved, renamed, and deleted files The original directory structure was scattered and unorganized. Changes are basically to make it look like kernel structure. --- ANDROID_3.4.5/arch/parisc/include/asm/spinlock.h | 198 ----------------------- 1 file changed, 198 deletions(-) delete mode 100644 ANDROID_3.4.5/arch/parisc/include/asm/spinlock.h (limited to 'ANDROID_3.4.5/arch/parisc/include/asm/spinlock.h') diff --git a/ANDROID_3.4.5/arch/parisc/include/asm/spinlock.h b/ANDROID_3.4.5/arch/parisc/include/asm/spinlock.h deleted file mode 100644 index 3516e0b2..00000000 --- a/ANDROID_3.4.5/arch/parisc/include/asm/spinlock.h +++ /dev/null @@ -1,198 +0,0 @@ -#ifndef __ASM_SPINLOCK_H -#define __ASM_SPINLOCK_H - -#include -#include -#include -#include - -static inline int arch_spin_is_locked(arch_spinlock_t *x) -{ - volatile unsigned int *a = __ldcw_align(x); - return *a == 0; -} - -#define arch_spin_lock(lock) arch_spin_lock_flags(lock, 0) -#define arch_spin_unlock_wait(x) \ - do { cpu_relax(); } while (arch_spin_is_locked(x)) - -static inline void arch_spin_lock_flags(arch_spinlock_t *x, - unsigned long flags) -{ - volatile unsigned int *a; - - mb(); - a = __ldcw_align(x); - while (__ldcw(a) == 0) - while (*a == 0) - if (flags & PSW_SM_I) { - local_irq_enable(); - cpu_relax(); - local_irq_disable(); - } else - cpu_relax(); - mb(); -} - -static inline void arch_spin_unlock(arch_spinlock_t *x) -{ - volatile unsigned int *a; - mb(); - a = __ldcw_align(x); - *a = 1; - mb(); -} - -static inline int arch_spin_trylock(arch_spinlock_t *x) -{ - volatile unsigned int *a; - int ret; - - mb(); - a = __ldcw_align(x); - ret = __ldcw(a) != 0; - mb(); - - return ret; -} - -/* - * Read-write spinlocks, allowing multiple readers but only one writer. - * Linux rwlocks are unfair to writers; they can be starved for an indefinite - * time by readers. With care, they can also be taken in interrupt context. - * - * In the PA-RISC implementation, we have a spinlock and a counter. - * Readers use the lock to serialise their access to the counter (which - * records how many readers currently hold the lock). - * Writers hold the spinlock, preventing any readers or other writers from - * grabbing the rwlock. - */ - -/* Note that we have to ensure interrupts are disabled in case we're - * interrupted by some other code that wants to grab the same read lock */ -static __inline__ void arch_read_lock(arch_rwlock_t *rw) -{ - unsigned long flags; - local_irq_save(flags); - arch_spin_lock_flags(&rw->lock, flags); - rw->counter++; - arch_spin_unlock(&rw->lock); - local_irq_restore(flags); -} - -/* Note that we have to ensure interrupts are disabled in case we're - * interrupted by some other code that wants to grab the same read lock */ -static __inline__ void arch_read_unlock(arch_rwlock_t *rw) -{ - unsigned long flags; - local_irq_save(flags); - arch_spin_lock_flags(&rw->lock, flags); - rw->counter--; - arch_spin_unlock(&rw->lock); - local_irq_restore(flags); -} - -/* Note that we have to ensure interrupts are disabled in case we're - * interrupted by some other code that wants to grab the same read lock */ -static __inline__ int arch_read_trylock(arch_rwlock_t *rw) -{ - unsigned long flags; - retry: - local_irq_save(flags); - if (arch_spin_trylock(&rw->lock)) { - rw->counter++; - arch_spin_unlock(&rw->lock); - local_irq_restore(flags); - return 1; - } - - local_irq_restore(flags); - /* If write-locked, we fail to acquire the lock */ - if (rw->counter < 0) - return 0; - - /* Wait until we have a realistic chance at the lock */ - while (arch_spin_is_locked(&rw->lock) && rw->counter >= 0) - cpu_relax(); - - goto retry; -} - -/* Note that we have to ensure interrupts are disabled in case we're - * interrupted by some other code that wants to read_trylock() this lock */ -static __inline__ void arch_write_lock(arch_rwlock_t *rw) -{ - unsigned long flags; -retry: - local_irq_save(flags); - arch_spin_lock_flags(&rw->lock, flags); - - if (rw->counter != 0) { - arch_spin_unlock(&rw->lock); - local_irq_restore(flags); - - while (rw->counter != 0) - cpu_relax(); - - goto retry; - } - - rw->counter = -1; /* mark as write-locked */ - mb(); - local_irq_restore(flags); -} - -static __inline__ void arch_write_unlock(arch_rwlock_t *rw) -{ - rw->counter = 0; - arch_spin_unlock(&rw->lock); -} - -/* Note that we have to ensure interrupts are disabled in case we're - * interrupted by some other code that wants to read_trylock() this lock */ -static __inline__ int arch_write_trylock(arch_rwlock_t *rw) -{ - unsigned long flags; - int result = 0; - - local_irq_save(flags); - if (arch_spin_trylock(&rw->lock)) { - if (rw->counter == 0) { - rw->counter = -1; - result = 1; - } else { - /* Read-locked. Oh well. */ - arch_spin_unlock(&rw->lock); - } - } - local_irq_restore(flags); - - return result; -} - -/* - * read_can_lock - would read_trylock() succeed? - * @lock: the rwlock in question. - */ -static __inline__ int arch_read_can_lock(arch_rwlock_t *rw) -{ - return rw->counter >= 0; -} - -/* - * write_can_lock - would write_trylock() succeed? - * @lock: the rwlock in question. - */ -static __inline__ int arch_write_can_lock(arch_rwlock_t *rw) -{ - return !rw->counter; -} - -#define arch_read_lock_flags(lock, flags) arch_read_lock(lock) -#define arch_write_lock_flags(lock, flags) arch_write_lock(lock) - -#define arch_spin_relax(lock) cpu_relax() -#define arch_read_relax(lock) cpu_relax() -#define arch_write_relax(lock) cpu_relax() - -#endif /* __ASM_SPINLOCK_H */ -- cgit