#ifndef _ALPHA_SPINLOCK_H #define _ALPHA_SPINLOCK_H #include #include #include #include /* * 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. */ typedef struct { volatile unsigned int lock /*__attribute__((aligned(32))) */; #if CONFIG_DEBUG_SPINLOCK int on_cpu; int line_no; void *previous; struct task_struct * task; const char *base_file; #endif } spinlock_t; #if CONFIG_DEBUG_SPINLOCK #define SPIN_LOCK_UNLOCKED (spinlock_t) {0, -1, 0, 0, 0, 0} #define spin_lock_init(x) \ ((x)->lock = 0, (x)->on_cpu = -1, (x)->previous = 0, (x)->task = 0) #else #define SPIN_LOCK_UNLOCKED (spinlock_t) { 0 } #define spin_lock_init(x) ((x)->lock = 0) #endif #define spin_is_locked(x) ((x)->lock != 0) #define spin_unlock_wait(x) ({ do { barrier(); } while ((x)->lock); }) #if CONFIG_DEBUG_SPINLOCK extern void spin_unlock(spinlock_t * lock); extern void debug_spin_lock(spinlock_t * lock, const char *, int); extern int debug_spin_trylock(spinlock_t * lock, const char *, int); #define spin_lock(LOCK) debug_spin_lock(LOCK, __BASE_FILE__, __LINE__) #define spin_trylock(LOCK) debug_spin_trylock(LOCK, __BASE_FILE__, __LINE__) #define spin_lock_own(LOCK, LOCATION) \ do { \ if (!((LOCK)->lock && (LOCK)->on_cpu == smp_processor_id())) \ printk("%s: called on %d from %p but lock %s on %d\n", \ LOCATION, smp_processor_id(), \ __builtin_return_address(0), \ (LOCK)->lock ? "taken" : "freed", (LOCK)->on_cpu); \ } while (0) #else static inline void spin_unlock(spinlock_t * lock) { mb(); lock->lock = 0; } static inline void spin_lock(spinlock_t * lock) { long tmp; /* Use sub-sections to put the actual loop at the end of this object file's text section so as to perfect branch prediction. */ __asm__ __volatile__( "1: ldl_l %0,%1\n" " blbs %0,2f\n" " or %0,1,%0\n" " stl_c %0,%1\n" " beq %0,2f\n" " mb\n" ".subsection 2\n" "2: ldl %0,%1\n" " blbs %0,2b\n" " br 1b\n" ".previous" : "=&r" (tmp), "=m" (lock->lock) : "m"(lock->lock) : "memory"); } #define spin_trylock(lock) (!test_and_set_bit(0,(lock))) #define spin_lock_own(LOCK, LOCATION) ((void)0) #endif /* CONFIG_DEBUG_SPINLOCK */ /***********************************************************/ typedef struct { volatile int write_lock:1, read_counter:31; } /*__attribute__((aligned(32)))*/ rwlock_t; #define RW_LOCK_UNLOCKED (rwlock_t) { 0, 0 } #define rwlock_init(x) do { *(x) = RW_LOCK_UNLOCKED; } while(0) #if CONFIG_DEBUG_RWLOCK extern void write_lock(rwlock_t * lock); extern void read_lock(rwlock_t * lock); #else static inline void write_lock(rwlock_t * lock) { long regx; __asm__ __volatile__( "1: ldl_l %1,%0\n" " bne %1,6f\n" " or $31,1,%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" (*(volatile int *)lock), "=&r" (regx) : "0" (*(volatile int *)lock) : "memory"); } static inline void read_lock(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" "4: mb\n" ".subsection 2\n" "6: ldl %1,%0\n" " blbs %1,6b\n" " br 1b\n" ".previous" : "=m" (*(volatile int *)lock), "=&r" (regx) : "m" (*(volatile int *)lock) : "memory"); } #endif /* CONFIG_DEBUG_RWLOCK */ static inline void write_unlock(rwlock_t * lock) { mb(); *(volatile int *)lock = 0; } static inline void read_unlock(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" (*(volatile int *)lock), "=&r" (regx) : "m" (*(volatile int *)lock) : "memory"); } #endif /* _ALPHA_SPINLOCK_H */