diff options
Diffstat (limited to 'include/asm-x86_64/spinlock.h')
| -rw-r--r-- | include/asm-x86_64/spinlock.h | 80 |
1 files changed, 41 insertions, 39 deletions
diff --git a/include/asm-x86_64/spinlock.h b/include/asm-x86_64/spinlock.h index 248a79f..3daf5b0 100644 --- a/include/asm-x86_64/spinlock.h +++ b/include/asm-x86_64/spinlock.h @@ -4,6 +4,7 @@ #include <asm/atomic.h> #include <asm/rwlock.h> #include <asm/page.h> +#include <asm/processor.h> /* * Your basic SMP spinlocks, allowing only a single CPU anywhere @@ -16,31 +17,23 @@ * (the type definitions are in asm/spinlock_types.h) */ -#define __raw_spin_is_locked(x) \ - (*(volatile signed int *)(&(x)->slock) <= 0) - -#define __raw_spin_lock_string \ - "\n1:\t" \ - LOCK_PREFIX " ; decl %0\n\t" \ - "js 2f\n" \ - LOCK_SECTION_START("") \ - "2:\t" \ - "rep;nop\n\t" \ - "cmpl $0,%0\n\t" \ - "jle 2b\n\t" \ - "jmp 1b\n" \ - LOCK_SECTION_END - -#define __raw_spin_lock_string_up \ - "\n\tdecl %0" - -#define __raw_spin_unlock_string \ - "movl $1,%0" \ - :"=m" (lock->slock) : : "memory" +static inline int __raw_spin_is_locked(raw_spinlock_t *lock) +{ + return *(volatile signed int *)(&(lock)->slock) <= 0; +} static inline void __raw_spin_lock(raw_spinlock_t *lock) { - asm volatile(__raw_spin_lock_string : "=m" (lock->slock) : : "memory"); + asm volatile( + "\n1:\t" + LOCK_PREFIX " ; decl %0\n\t" + "jns 2f\n" + "3:\n" + "rep;nop\n\t" + "cmpl $0,%0\n\t" + "jle 3b\n\t" + "jmp 1b\n" + "2:\t" : "=m" (lock->slock) : : "memory"); } #define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock) @@ -49,7 +42,7 @@ static inline int __raw_spin_trylock(raw_spinlock_t *lock) { int oldval; - __asm__ __volatile__( + asm volatile( "xchgl %0,%1" :"=q" (oldval), "=m" (lock->slock) :"0" (0) : "memory"); @@ -59,13 +52,14 @@ static inline int __raw_spin_trylock(raw_spinlock_t *lock) static inline void __raw_spin_unlock(raw_spinlock_t *lock) { - __asm__ __volatile__( - __raw_spin_unlock_string - ); + asm volatile("movl $1,%0" :"=m" (lock->slock) :: "memory"); } -#define __raw_spin_unlock_wait(lock) \ - do { while (__raw_spin_is_locked(lock)) cpu_relax(); } while (0) +static inline void __raw_spin_unlock_wait(raw_spinlock_t *lock) +{ + while (__raw_spin_is_locked(lock)) + cpu_relax(); +} /* * Read-write spinlocks, allowing multiple readers @@ -79,26 +73,34 @@ static inline void __raw_spin_unlock(raw_spinlock_t *lock) * * On x86, we implement read-write locks as a 32-bit counter * with the high bit (sign) being the "contended" bit. - * - * The inline assembly is non-obvious. Think about it. - * - * Changed to use the same technique as rw semaphores. See - * semaphore.h for details. -ben - * - * the helpers are in arch/i386/kernel/semaphore.c */ -#define __raw_read_can_lock(x) ((int)(x)->lock > 0) -#define __raw_write_can_lock(x) ((x)->lock == RW_LOCK_BIAS) +static inline int __raw_read_can_lock(raw_rwlock_t *lock) +{ + return (int)(lock)->lock > 0; +} + +static inline int __raw_write_can_lock(raw_rwlock_t *lock) +{ + return (lock)->lock == RW_LOCK_BIAS; +} static inline void __raw_read_lock(raw_rwlock_t *rw) { - __build_read_lock(rw, "__read_lock_failed"); + asm volatile(LOCK_PREFIX "subl $1,(%0)\n\t" + "jns 1f\n" + "call __read_lock_failed\n" + "1:\n" + ::"D" (rw), "i" (RW_LOCK_BIAS) : "memory"); } static inline void __raw_write_lock(raw_rwlock_t *rw) { - __build_write_lock(rw, "__write_lock_failed"); + asm volatile(LOCK_PREFIX "subl %1,(%0)\n\t" + "jz 1f\n" + "\tcall __write_lock_failed\n\t" + "1:\n" + ::"D" (rw), "i" (RW_LOCK_BIAS) : "memory"); } static inline int __raw_read_trylock(raw_rwlock_t *lock) |
