mirror of https://gitee.com/openkylin/linux.git
169 lines
3.2 KiB
C
169 lines
3.2 KiB
C
#ifndef __ASM_SPINLOCK_H
|
|
#define __ASM_SPINLOCK_H
|
|
|
|
#include <asm/system.h>
|
|
|
|
/*
|
|
* Simple spin lock operations.
|
|
*
|
|
* (the type definitions are in asm/raw_spinlock_types.h)
|
|
*/
|
|
|
|
#define __raw_spin_is_locked(x) ((x)->slock != 0)
|
|
#define __raw_spin_unlock_wait(lock) \
|
|
do { while (__raw_spin_is_locked(lock)) cpu_relax(); } while (0)
|
|
#define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock)
|
|
|
|
static inline void __raw_spin_lock(raw_spinlock_t *lock)
|
|
{
|
|
unsigned long tmp;
|
|
|
|
__asm__ __volatile__(
|
|
"b 1f # __raw_spin_lock\n\
|
|
2: lwzx %0,0,%1\n\
|
|
cmpwi 0,%0,0\n\
|
|
bne+ 2b\n\
|
|
1: lwarx %0,0,%1\n\
|
|
cmpwi 0,%0,0\n\
|
|
bne- 2b\n"
|
|
PPC405_ERR77(0,%1)
|
|
" stwcx. %2,0,%1\n\
|
|
bne- 2b\n\
|
|
isync"
|
|
: "=&r"(tmp)
|
|
: "r"(&lock->slock), "r"(1)
|
|
: "cr0", "memory");
|
|
}
|
|
|
|
static inline void __raw_spin_unlock(raw_spinlock_t *lock)
|
|
{
|
|
__asm__ __volatile__("eieio # __raw_spin_unlock": : :"memory");
|
|
lock->slock = 0;
|
|
}
|
|
|
|
#define __raw_spin_trylock(l) (!test_and_set_bit(0,(volatile unsigned long *)(&(l)->slock)))
|
|
|
|
/*
|
|
* Read-write spinlocks, allowing multiple readers
|
|
* but only one writer.
|
|
*
|
|
* NOTE! it is quite common to have readers in interrupts
|
|
* but no interrupt writers. For those circumstances we
|
|
* can "mix" irq-safe locks - any writer needs to get a
|
|
* irq-safe write-lock, but readers can get non-irqsafe
|
|
* read-locks.
|
|
*/
|
|
|
|
#define __raw_read_can_lock(rw) ((rw)->lock >= 0)
|
|
#define __raw_write_can_lock(rw) (!(rw)->lock)
|
|
|
|
static __inline__ int __raw_read_trylock(raw_rwlock_t *rw)
|
|
{
|
|
signed int tmp;
|
|
|
|
__asm__ __volatile__(
|
|
"2: lwarx %0,0,%1 # read_trylock\n\
|
|
addic. %0,%0,1\n\
|
|
ble- 1f\n"
|
|
PPC405_ERR77(0,%1)
|
|
" stwcx. %0,0,%1\n\
|
|
bne- 2b\n\
|
|
isync\n\
|
|
1:"
|
|
: "=&r"(tmp)
|
|
: "r"(&rw->lock)
|
|
: "cr0", "memory");
|
|
|
|
return tmp > 0;
|
|
}
|
|
|
|
static __inline__ void __raw_read_lock(raw_rwlock_t *rw)
|
|
{
|
|
signed int tmp;
|
|
|
|
__asm__ __volatile__(
|
|
"b 2f # read_lock\n\
|
|
1: lwzx %0,0,%1\n\
|
|
cmpwi 0,%0,0\n\
|
|
blt+ 1b\n\
|
|
2: lwarx %0,0,%1\n\
|
|
addic. %0,%0,1\n\
|
|
ble- 1b\n"
|
|
PPC405_ERR77(0,%1)
|
|
" stwcx. %0,0,%1\n\
|
|
bne- 2b\n\
|
|
isync"
|
|
: "=&r"(tmp)
|
|
: "r"(&rw->lock)
|
|
: "cr0", "memory");
|
|
}
|
|
|
|
static __inline__ void __raw_read_unlock(raw_rwlock_t *rw)
|
|
{
|
|
signed int tmp;
|
|
|
|
__asm__ __volatile__(
|
|
"eieio # read_unlock\n\
|
|
1: lwarx %0,0,%1\n\
|
|
addic %0,%0,-1\n"
|
|
PPC405_ERR77(0,%1)
|
|
" stwcx. %0,0,%1\n\
|
|
bne- 1b"
|
|
: "=&r"(tmp)
|
|
: "r"(&rw->lock)
|
|
: "cr0", "memory");
|
|
}
|
|
|
|
static __inline__ int __raw_write_trylock(raw_rwlock_t *rw)
|
|
{
|
|
signed int tmp;
|
|
|
|
__asm__ __volatile__(
|
|
"2: lwarx %0,0,%1 # write_trylock\n\
|
|
cmpwi 0,%0,0\n\
|
|
bne- 1f\n"
|
|
PPC405_ERR77(0,%1)
|
|
" stwcx. %2,0,%1\n\
|
|
bne- 2b\n\
|
|
isync\n\
|
|
1:"
|
|
: "=&r"(tmp)
|
|
: "r"(&rw->lock), "r"(-1)
|
|
: "cr0", "memory");
|
|
|
|
return tmp == 0;
|
|
}
|
|
|
|
static __inline__ void __raw_write_lock(raw_rwlock_t *rw)
|
|
{
|
|
signed int tmp;
|
|
|
|
__asm__ __volatile__(
|
|
"b 2f # write_lock\n\
|
|
1: lwzx %0,0,%1\n\
|
|
cmpwi 0,%0,0\n\
|
|
bne+ 1b\n\
|
|
2: lwarx %0,0,%1\n\
|
|
cmpwi 0,%0,0\n\
|
|
bne- 1b\n"
|
|
PPC405_ERR77(0,%1)
|
|
" stwcx. %2,0,%1\n\
|
|
bne- 2b\n\
|
|
isync"
|
|
: "=&r"(tmp)
|
|
: "r"(&rw->lock), "r"(-1)
|
|
: "cr0", "memory");
|
|
}
|
|
|
|
static __inline__ void __raw_write_unlock(raw_rwlock_t *rw)
|
|
{
|
|
__asm__ __volatile__("eieio # write_unlock": : :"memory");
|
|
rw->lock = 0;
|
|
}
|
|
|
|
#define _raw_spin_relax(lock) cpu_relax()
|
|
#define _raw_read_relax(lock) cpu_relax()
|
|
#define _raw_write_relax(lock) cpu_relax()
|
|
|
|
#endif /* __ASM_SPINLOCK_H */
|