e5931943d0
Name space cleanup for rwlock functions. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: linux-arch@vger.kernel.org
176 lines
3.2 KiB
C
176 lines
3.2 KiB
C
#ifndef _ALPHA_SPINLOCK_H
|
|
#define _ALPHA_SPINLOCK_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.
|
|
*/
|
|
|
|
#define arch_spin_lock_flags(lock, flags) arch_spin_lock(lock)
|
|
#define arch_spin_is_locked(x) ((x)->lock != 0)
|
|
#define arch_spin_unlock_wait(x) \
|
|
do { cpu_relax(); } while ((x)->lock)
|
|
|
|
static inline void arch_spin_unlock(arch_spinlock_t * lock)
|
|
{
|
|
mb();
|
|
lock->lock = 0;
|
|
}
|
|
|
|
static inline void arch_spin_lock(arch_spinlock_t * lock)
|
|
{
|
|
long tmp;
|
|
|
|
__asm__ __volatile__(
|
|
"1: ldl_l %0,%1\n"
|
|
" bne %0,2f\n"
|
|
" lda %0,1\n"
|
|
" stl_c %0,%1\n"
|
|
" beq %0,2f\n"
|
|
" mb\n"
|
|
".subsection 2\n"
|
|
"2: ldl %0,%1\n"
|
|
" bne %0,2b\n"
|
|
" br 1b\n"
|
|
".previous"
|
|
: "=&r" (tmp), "=m" (lock->lock)
|
|
: "m"(lock->lock) : "memory");
|
|
}
|
|
|
|
static inline int arch_spin_trylock(arch_spinlock_t *lock)
|
|
{
|
|
return !test_and_set_bit(0, &lock->lock);
|
|
}
|
|
|
|
/***********************************************************/
|
|
|
|
static inline int arch_read_can_lock(arch_rwlock_t *lock)
|
|
{
|
|
return (lock->lock & 1) == 0;
|
|
}
|
|
|
|
static inline int arch_write_can_lock(arch_rwlock_t *lock)
|
|
{
|
|
return lock->lock == 0;
|
|
}
|
|
|
|
static inline void arch_read_lock(arch_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"
|
|
" mb\n"
|
|
".subsection 2\n"
|
|
"6: ldl %1,%0\n"
|
|
" blbs %1,6b\n"
|
|
" br 1b\n"
|
|
".previous"
|
|
: "=m" (*lock), "=&r" (regx)
|
|
: "m" (*lock) : "memory");
|
|
}
|
|
|
|
static inline void arch_write_lock(arch_rwlock_t *lock)
|
|
{
|
|
long regx;
|
|
|
|
__asm__ __volatile__(
|
|
"1: ldl_l %1,%0\n"
|
|
" bne %1,6f\n"
|
|
" lda %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" (*lock), "=&r" (regx)
|
|
: "m" (*lock) : "memory");
|
|
}
|
|
|
|
static inline int arch_read_trylock(arch_rwlock_t * lock)
|
|
{
|
|
long regx;
|
|
int success;
|
|
|
|
__asm__ __volatile__(
|
|
"1: ldl_l %1,%0\n"
|
|
" lda %2,0\n"
|
|
" blbs %1,2f\n"
|
|
" subl %1,2,%2\n"
|
|
" stl_c %2,%0\n"
|
|
" beq %2,6f\n"
|
|
"2: mb\n"
|
|
".subsection 2\n"
|
|
"6: br 1b\n"
|
|
".previous"
|
|
: "=m" (*lock), "=&r" (regx), "=&r" (success)
|
|
: "m" (*lock) : "memory");
|
|
|
|
return success;
|
|
}
|
|
|
|
static inline int arch_write_trylock(arch_rwlock_t * lock)
|
|
{
|
|
long regx;
|
|
int success;
|
|
|
|
__asm__ __volatile__(
|
|
"1: ldl_l %1,%0\n"
|
|
" lda %2,0\n"
|
|
" bne %1,2f\n"
|
|
" lda %2,1\n"
|
|
" stl_c %2,%0\n"
|
|
" beq %2,6f\n"
|
|
"2: mb\n"
|
|
".subsection 2\n"
|
|
"6: br 1b\n"
|
|
".previous"
|
|
: "=m" (*lock), "=&r" (regx), "=&r" (success)
|
|
: "m" (*lock) : "memory");
|
|
|
|
return success;
|
|
}
|
|
|
|
static inline void arch_read_unlock(arch_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" (*lock), "=&r" (regx)
|
|
: "m" (*lock) : "memory");
|
|
}
|
|
|
|
static inline void arch_write_unlock(arch_rwlock_t * lock)
|
|
{
|
|
mb();
|
|
lock->lock = 0;
|
|
}
|
|
|
|
#define arch_read_lock_flags(lock, flags) arch_read_lock(lock)
|
|
#define arch_write_lock_flags(lock, flags) arch_write_lock(lock)
|
|
|
|
#define arch_spin_relax(lock) cpu_relax()
|
|
#define arch_read_relax(lock) cpu_relax()
|
|
#define arch_write_relax(lock) cpu_relax()
|
|
|
|
#endif /* _ALPHA_SPINLOCK_H */
|