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#ifndef __ASM_SMPLOCK_H

#define __ASM_SMPLOCK_H

/*

 * <asm/smplock.h>

 *

 * i386 SMP lock implementation

 */

#include <linux/interrupt.h>

#include <linux/spinlock.h>

#include <linux/sched.h>

#include <asm/current.h>

extern spinlock_cacheline_t kernel_flag_cacheline;

#define kernel_flag kernel_flag_cacheline.lock      

#define kernel_locked()         spin_is_locked(&kernel_flag)

/*

 * Release global kernel lock and global interrupt lock

 */

#define release_kernel_lock(task, cpu) \

do { \

        if (task->lock_depth >= 0) \

                spin_unlock(&kernel_flag); \

        release_irqlock(cpu); \

        __sti(); \

} while (0)

/*

 * Re-acquire the kernel lock

 */

#define reacquire_kernel_lock(task) \

do { \

        if (task->lock_depth >= 0) \

                spin_lock(&kernel_flag); \

} while (0)

/*

 * Getting the big kernel lock.

 *

 * This cannot happen asynchronously,

 * so we only need to worry about other

 * CPU's.

 */

static __inline__ void lock_kernel(void)

{

#if 1

        if (!++current->lock_depth)

                spin_lock(&kernel_flag);

#else

        __asm__ __volatile__(

                "incl %1\n\t"

                "jne 9f"

                spin_lock_string

                "\n9:"

                :"=m" (__dummy_lock(&kernel_flag)),

                 "=m" (current->lock_depth));

#endif

}

static __inline__ void unlock_kernel(void)

{

        if (current->lock_depth < 0)

                out_of_line_bug();

#if 1

        if (--current->lock_depth < 0)

                spin_unlock(&kernel_flag);

#else

        __asm__ __volatile__(

                "decl %1\n\t"

                "jns 9f\n\t"

                spin_unlock_string

                "\n9:"

                :"=m" (__dummy_lock(&kernel_flag)),

                 "=m" (current->lock_depth));

#endif

}

#endif /* __ASM_SMPLOCK_H */