mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-30 16:07:39 +00:00
1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
215 lines
4.1 KiB
C
215 lines
4.1 KiB
C
#ifndef __ASM_SPINLOCK_H
|
|
#define __ASM_SPINLOCK_H
|
|
|
|
#include <asm/system.h>
|
|
|
|
/*
|
|
* Simple spin lock operations.
|
|
*/
|
|
|
|
typedef struct {
|
|
volatile unsigned long lock;
|
|
#ifdef CONFIG_DEBUG_SPINLOCK
|
|
volatile unsigned long owner_pc;
|
|
volatile unsigned long owner_cpu;
|
|
#endif
|
|
#ifdef CONFIG_PREEMPT
|
|
unsigned int break_lock;
|
|
#endif
|
|
} spinlock_t;
|
|
|
|
#ifdef __KERNEL__
|
|
#ifdef CONFIG_DEBUG_SPINLOCK
|
|
#define SPINLOCK_DEBUG_INIT , 0, 0
|
|
#else
|
|
#define SPINLOCK_DEBUG_INIT /* */
|
|
#endif
|
|
|
|
#define SPIN_LOCK_UNLOCKED (spinlock_t) { 0 SPINLOCK_DEBUG_INIT }
|
|
|
|
#define spin_lock_init(x) do { *(x) = SPIN_LOCK_UNLOCKED; } while(0)
|
|
#define spin_is_locked(x) ((x)->lock != 0)
|
|
#define spin_unlock_wait(x) do { barrier(); } while(spin_is_locked(x))
|
|
#define _raw_spin_lock_flags(lock, flags) _raw_spin_lock(lock)
|
|
|
|
#ifndef CONFIG_DEBUG_SPINLOCK
|
|
|
|
static inline void _raw_spin_lock(spinlock_t *lock)
|
|
{
|
|
unsigned long tmp;
|
|
|
|
__asm__ __volatile__(
|
|
"b 1f # 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->lock), "r"(1)
|
|
: "cr0", "memory");
|
|
}
|
|
|
|
static inline void _raw_spin_unlock(spinlock_t *lock)
|
|
{
|
|
__asm__ __volatile__("eieio # spin_unlock": : :"memory");
|
|
lock->lock = 0;
|
|
}
|
|
|
|
#define _raw_spin_trylock(l) (!test_and_set_bit(0,&(l)->lock))
|
|
|
|
#else
|
|
|
|
extern void _raw_spin_lock(spinlock_t *lock);
|
|
extern void _raw_spin_unlock(spinlock_t *lock);
|
|
extern int _raw_spin_trylock(spinlock_t *lock);
|
|
|
|
#endif
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
typedef struct {
|
|
volatile signed int lock;
|
|
#ifdef CONFIG_PREEMPT
|
|
unsigned int break_lock;
|
|
#endif
|
|
} rwlock_t;
|
|
|
|
#define RW_LOCK_UNLOCKED (rwlock_t) { 0 }
|
|
#define rwlock_init(lp) do { *(lp) = RW_LOCK_UNLOCKED; } while(0)
|
|
|
|
#define read_can_lock(rw) ((rw)->lock >= 0)
|
|
#define write_can_lock(rw) (!(rw)->lock)
|
|
|
|
#ifndef CONFIG_DEBUG_SPINLOCK
|
|
|
|
static __inline__ int _raw_read_trylock(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(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(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(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(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(rwlock_t *rw)
|
|
{
|
|
__asm__ __volatile__("eieio # write_unlock": : :"memory");
|
|
rw->lock = 0;
|
|
}
|
|
|
|
#else
|
|
|
|
extern void _raw_read_lock(rwlock_t *rw);
|
|
extern void _raw_read_unlock(rwlock_t *rw);
|
|
extern void _raw_write_lock(rwlock_t *rw);
|
|
extern void _raw_write_unlock(rwlock_t *rw);
|
|
extern int _raw_read_trylock(rwlock_t *rw);
|
|
extern int _raw_write_trylock(rwlock_t *rw);
|
|
|
|
#endif
|
|
|
|
#endif /* __ASM_SPINLOCK_H */
|
|
#endif /* __KERNEL__ */
|