i386/linux-2.3.21/include/asm-ppc/spinlock.h

   1 #ifndef __ASM_SPINLOCK_H
   2 #define __ASM_SPINLOCK_H
   3
   4 /*
   5  * Simple spin lock operations.
   6  */
   7
   8 typedef struct {
   9         volatile unsigned long lock;
  10         volatile unsigned long owner_pc;
  11         volatile unsigned long owner_cpu;
  12 } spinlock_t;
  13
  14 #define SPIN_LOCK_UNLOCKED      (spinlock_t) { 0, 0, 0 }
  15 #define spin_lock_init(lp)      do { (lp)->lock = 0; } while(0)
  16 #define spin_unlock_wait(lp)    do { barrier(); } while((lp)->lock)
  17
  18 extern void _spin_lock(spinlock_t *lock);
  19 extern void _spin_unlock(spinlock_t *lock);
  20 extern int spin_trylock(spinlock_t *lock);
  21
  22 #define spin_lock(lp)                   _spin_lock(lp)
  23 #define spin_unlock(lp)                 _spin_unlock(lp)
  24
  25 extern unsigned long __spin_trylock(volatile unsigned long *lock);
  26
  27 /*
  28  * Read-write spinlocks, allowing multiple readers
  29  * but only one writer.
  30  *
  31  * NOTE! it is quite common to have readers in interrupts
  32  * but no interrupt writers. For those circumstances we
  33  * can "mix" irq-safe locks - any writer needs to get a
  34  * irq-safe write-lock, but readers can get non-irqsafe
  35  * read-locks.
  36  */
  37 typedef struct {
  38         volatile unsigned long lock;
  39         volatile unsigned long owner_pc;
  40 } rwlock_t;
  41
  42 #define RW_LOCK_UNLOCKED (rwlock_t) { 0, 0 }
  43
  44 extern void _read_lock(rwlock_t *rw);
  45 extern void _read_unlock(rwlock_t *rw);
  46 extern void _write_lock(rwlock_t *rw);
  47 extern void _write_unlock(rwlock_t *rw);
  48
  49 #define read_lock(rw)           _read_lock(rw)
  50 #define write_lock(rw)          _write_lock(rw)
  51 #define write_unlock(rw)        _write_unlock(rw)
  52 #define read_unlock(rw)         _read_unlock(rw)
  53
  54 #endif /* __ASM_SPINLOCK_H */