Commit dcf82962 authored by Tony Luck's avatar Tony Luck
Browse files

Pull lameter-spinlock-optimization into release branch

parents 02b3e4e2 f5210891

include/asm-ia64/spinlock.h

+24 −9
Original line number Diff line number Diff line
@@ -93,7 +93,15 @@ _raw_spin_lock_flags (spinlock_t *lock, unsigned long flags) 
# endif /* CONFIG_MCKINLEY */

#endif

}



#define _raw_spin_lock(lock) _raw_spin_lock_flags(lock, 0)



/* Unlock by doing an ordered store and releasing the cacheline with nta */

static inline void _raw_spin_unlock(spinlock_t *x) {

	barrier();

	asm volatile ("st4.rel.nta [%0] = r0\n\t" :: "r"(x));

}



#else /* !ASM_SUPPORTED */

#define _raw_spin_lock_flags(lock, flags) _raw_spin_lock(lock)

# define _raw_spin_lock(x)								\
@@ -109,16 +117,16 @@ do { \ 
		} while (ia64_spinlock_val);						\

	}										\

} while (0)

#define _raw_spin_unlock(x)	do { barrier(); ((spinlock_t *) x)->lock = 0; } while (0)

#endif /* !ASM_SUPPORTED */



#define spin_is_locked(x)	((x)->lock != 0)

#define _raw_spin_unlock(x)	do { barrier(); ((spinlock_t *) x)->lock = 0; } while (0)

#define _raw_spin_trylock(x)	(cmpxchg_acq(&(x)->lock, 0, 1) == 0)

#define spin_unlock_wait(x)	do { barrier(); } while ((x)->lock)



typedef struct {

	volatile unsigned int read_counter	: 31;

	volatile unsigned int write_lock	:  1;

	volatile unsigned int read_counter	: 24;

	volatile unsigned int write_lock	:  8;

#ifdef CONFIG_PREEMPT

	unsigned int break_lock;

#endif
@@ -174,6 +182,13 @@ do { \ 
	(result == 0);								\

})



static inline void _raw_write_unlock(rwlock_t *x)

{

	u8 *y = (u8 *)x;

	barrier();

	asm volatile ("st1.rel.nta [%0] = r0\n\t" :: "r"(y+3) : "memory" );

}



#else /* !ASM_SUPPORTED */



#define _raw_write_lock(l)								\
@@ -195,14 +210,14 @@ do { \ 
	(ia64_val == 0);						\

})



static inline void _raw_write_unlock(rwlock_t *x)

{

	barrier();

	x->write_lock = 0;

}



#endif /* !ASM_SUPPORTED */



#define _raw_read_trylock(lock) generic_raw_read_trylock(lock)



#define _raw_write_unlock(x)								\

({											\

	smp_mb__before_clear_bit();	/* need barrier before releasing lock... */	\

	clear_bit(31, (x));								\

})



#endif /*  _ASM_IA64_SPINLOCK_H */