| #ifndef _ALPHA_SPINLOCK_H |
| #define _ALPHA_SPINLOCK_H |
| |
| #include <linux/config.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. |
| */ |
| |
| 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 */ |