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/*
* <asm/smplock.h>
*
* Default SMP lock implementation
*/
#ifndef _ASM_SMPLOCK_H
#define _ASM_SMPLOCK_H
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
extern spinlock_t kernel_flag;
#define kernel_locked() spin_is_locked(&kernel_flag)
/*
* Release global kernel lock and global interrupt lock
*/
static __inline__ void release_kernel_lock(struct task_struct *task, int cpu)
{
if (task->lock_depth >= 0)
spin_unlock(&kernel_flag);
release_irqlock(cpu);
__sti();
}
/*
* Re-acquire the kernel lock
*/
static __inline__ void reacquire_kernel_lock(struct task_struct *task)
{
if (task->lock_depth >= 0)
spin_lock(&kernel_flag);
}
/*
* 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 (!++current->lock_depth)
spin_lock(&kernel_flag);
}
static __inline__ void unlock_kernel(void)
{
if (--current->lock_depth < 0)
spin_unlock(&kernel_flag);
}
#endif /* _ASM_SMPLOCK_H */
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