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powerpc: Use rwsem.h from generic location 

As of commit dd472da38, rwsem.h was moved into asm-generic.
This patch removes the arch file and points the build at
its new location.

Signed-off-by: Richard Kuo <rkuo@codeaurora.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Richard Kuo 2011-11-29 08:28:20 +00:00 committed by Benjamin Herrenschmidt
parent 1e7342e778
commit 0766387bcf
2 changed files with 2 additions and 132 deletions
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2
arch/powerpc/include/asm/Kbuild
View File

@ -34,3 +34,5 @@ header-y += termios.h
header-y += types.h
header-y += ucontext.h
header-y += unistd.h
generic-y += rwsem.h

132
arch/powerpc/include/asm/rwsem.h
View File

@ -1,132 +0,0 @@
#ifndef _ASM_POWERPC_RWSEM_H
#define _ASM_POWERPC_RWSEM_H
#ifndef _LINUX_RWSEM_H
#error "Please don't include <asm/rwsem.h> directly, use <linux/rwsem.h> instead."
#endif
#ifdef __KERNEL__
/*
* R/W semaphores for PPC using the stuff in lib/rwsem.c.
* Adapted largely from include/asm-i386/rwsem.h
* by Paul Mackerras <paulus@samba.org>.
*/
/*
* the semaphore definition
*/
#ifdef CONFIG_PPC64
# define RWSEM_ACTIVE_MASK 0xffffffffL
#else
# define RWSEM_ACTIVE_MASK 0x0000ffffL
#endif
#define RWSEM_UNLOCKED_VALUE 0x00000000L
#define RWSEM_ACTIVE_BIAS 0x00000001L
#define RWSEM_WAITING_BIAS (-RWSEM_ACTIVE_MASK-1)
#define RWSEM_ACTIVE_READ_BIAS RWSEM_ACTIVE_BIAS
#define RWSEM_ACTIVE_WRITE_BIAS (RWSEM_WAITING_BIAS + RWSEM_ACTIVE_BIAS)
/*
* lock for reading
*/
static inline void __down_read(struct rw_semaphore *sem)
{
if (unlikely(atomic_long_inc_return((atomic_long_t *)&sem->count) <= 0))
rwsem_down_read_failed(sem);
}
static inline int __down_read_trylock(struct rw_semaphore *sem)
{
long tmp;
while ((tmp = sem->count) >= 0) {
if (tmp == cmpxchg(&sem->count, tmp,
tmp + RWSEM_ACTIVE_READ_BIAS)) {
return 1;
}
}
return 0;
}
/*
* lock for writing
*/
static inline void __down_write_nested(struct rw_semaphore *sem, int subclass)
{
long tmp;
tmp = atomic_long_add_return(RWSEM_ACTIVE_WRITE_BIAS,
(atomic_long_t *)&sem->count);
if (unlikely(tmp != RWSEM_ACTIVE_WRITE_BIAS))
rwsem_down_write_failed(sem);
}
static inline void __down_write(struct rw_semaphore *sem)
{
__down_write_nested(sem, 0);
}
static inline int __down_write_trylock(struct rw_semaphore *sem)
{
long tmp;
tmp = cmpxchg(&sem->count, RWSEM_UNLOCKED_VALUE,
RWSEM_ACTIVE_WRITE_BIAS);
return tmp == RWSEM_UNLOCKED_VALUE;
}
/*
* unlock after reading
*/
static inline void __up_read(struct rw_semaphore *sem)
{
long tmp;
tmp = atomic_long_dec_return((atomic_long_t *)&sem->count);
if (unlikely(tmp < -1 && (tmp & RWSEM_ACTIVE_MASK) == 0))
rwsem_wake(sem);
}
/*
* unlock after writing
*/
static inline void __up_write(struct rw_semaphore *sem)
{
if (unlikely(atomic_long_sub_return(RWSEM_ACTIVE_WRITE_BIAS,
(atomic_long_t *)&sem->count) < 0))
rwsem_wake(sem);
}
/*
* implement atomic add functionality
*/
static inline void rwsem_atomic_add(long delta, struct rw_semaphore *sem)
{
atomic_long_add(delta, (atomic_long_t *)&sem->count);
}
/*
* downgrade write lock to read lock
*/
static inline void __downgrade_write(struct rw_semaphore *sem)
{
long tmp;
tmp = atomic_long_add_return(-RWSEM_WAITING_BIAS,
(atomic_long_t *)&sem->count);
if (tmp < 0)
rwsem_downgrade_wake(sem);
}
/*
* implement exchange and add functionality
*/
static inline long rwsem_atomic_update(long delta, struct rw_semaphore *sem)
{
return atomic_long_add_return(delta, (atomic_long_t *)&sem->count);
}
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_RWSEM_H */