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- #ifndef _ALPHA_SPINLOCK_H
- #define _ALPHA_SPINLOCK_H
-
- #include <asm/system.h>
- #include <linux/kernel.h>
- #include <asm/current.h>
-
- /*
- * Simple spin lock operations. There are two variants, one clears IRQ's
- * on the local processor, one does not.
- *
- * We make no fairness assumptions. They have a cost.
- */
-
- #define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock)
- #define __raw_spin_is_locked(x) ((x)->lock != 0)
- #define __raw_spin_unlock_wait(x) \
- do { cpu_relax(); } while ((x)->lock)
-
- static inline void __raw_spin_unlock(raw_spinlock_t * lock)
- {
- mb();
- lock->lock = 0;
- }
-
- static inline void __raw_spin_lock(raw_spinlock_t * lock)
- {
- long tmp;
-
- __asm__ __volatile__(
- "1: ldl_l %0,%1\n"
- " bne %0,2f\n"
- " lda %0,1\n"
- " stl_c %0,%1\n"
- " beq %0,2f\n"
- " mb\n"
- ".subsection 2\n"
- "2: ldl %0,%1\n"
- " bne %0,2b\n"
- " br 1b\n"
- ".previous"
- : "=&r" (tmp), "=m" (lock->lock)
- : "m"(lock->lock) : "memory");
- }
-
- static inline int __raw_spin_trylock(raw_spinlock_t *lock)
- {
- return !test_and_set_bit(0, &lock->lock);
- }
-
- /***********************************************************/
-
- static inline int __raw_read_can_lock(raw_rwlock_t *lock)
- {
- return (lock->lock & 1) == 0;
- }
-
- static inline int __raw_write_can_lock(raw_rwlock_t *lock)
- {
- return lock->lock == 0;
- }
-
- static inline void __raw_read_lock(raw_rwlock_t *lock)
- {
- long regx;
-
- __asm__ __volatile__(
- "1: ldl_l %1,%0\n"
- " blbs %1,6f\n"
- " subl %1,2,%1\n"
- " stl_c %1,%0\n"
- " beq %1,6f\n"
- " mb\n"
- ".subsection 2\n"
- "6: ldl %1,%0\n"
- " blbs %1,6b\n"
- " br 1b\n"
- ".previous"
- : "=m" (*lock), "=&r" (regx)
- : "m" (*lock) : "memory");
- }
-
- static inline void __raw_write_lock(raw_rwlock_t *lock)
- {
- long regx;
-
- __asm__ __volatile__(
- "1: ldl_l %1,%0\n"
- " bne %1,6f\n"
- " lda %1,1\n"
- " stl_c %1,%0\n"
- " beq %1,6f\n"
- " mb\n"
- ".subsection 2\n"
- "6: ldl %1,%0\n"
- " bne %1,6b\n"
- " br 1b\n"
- ".previous"
- : "=m" (*lock), "=&r" (regx)
- : "m" (*lock) : "memory");
- }
-
- static inline int __raw_read_trylock(raw_rwlock_t * lock)
- {
- long regx;
- int success;
-
- __asm__ __volatile__(
- "1: ldl_l %1,%0\n"
- " lda %2,0\n"
- " blbs %1,2f\n"
- " subl %1,2,%2\n"
- " stl_c %2,%0\n"
- " beq %2,6f\n"
- "2: mb\n"
- ".subsection 2\n"
- "6: br 1b\n"
- ".previous"
- : "=m" (*lock), "=&r" (regx), "=&r" (success)
- : "m" (*lock) : "memory");
-
- return success;
- }
-
- static inline int __raw_write_trylock(raw_rwlock_t * lock)
- {
- long regx;
- int success;
-
- __asm__ __volatile__(
- "1: ldl_l %1,%0\n"
- " lda %2,0\n"
- " bne %1,2f\n"
- " lda %2,1\n"
- " stl_c %2,%0\n"
- " beq %2,6f\n"
- "2: mb\n"
- ".subsection 2\n"
- "6: br 1b\n"
- ".previous"
- : "=m" (*lock), "=&r" (regx), "=&r" (success)
- : "m" (*lock) : "memory");
-
- return success;
- }
-
- static inline void __raw_read_unlock(raw_rwlock_t * lock)
- {
- long regx;
- __asm__ __volatile__(
- " mb\n"
- "1: ldl_l %1,%0\n"
- " addl %1,2,%1\n"
- " stl_c %1,%0\n"
- " beq %1,6f\n"
- ".subsection 2\n"
- "6: br 1b\n"
- ".previous"
- : "=m" (*lock), "=&r" (regx)
- : "m" (*lock) : "memory");
- }
-
- static inline void __raw_write_unlock(raw_rwlock_t * lock)
- {
- mb();
- lock->lock = 0;
- }
-
- #endif /* _ALPHA_SPINLOCK_H */
-