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 #ifndef __LINUX_SMPLOCK_H
#define __LINUX_SMPLOCK_H
#include <linux/config.h>
#include <linux/sched.h>
#include <linux/spinlock.h>
#ifdef CONFIG_LOCK_KERNEL
#define kernel_locked()  (current->lock_depth >= 0)
extern int __lockfunc get_kernel_lock(void);
extern void __lockfunc put_kernel_lock(void);
/*
 * Release/re-acquire global kernel lock for the scheduler
 */
#define release_kernel_lock(tsk) do {   \
 if (unlikely((tsk)->lock_depth >= 0)) \
  put_kernel_lock();  \
} while (0)
/*
 * Non-SMP kernels will never block on the kernel lock,
 * so we are better off returning a constant zero from
 * reacquire_kernel_lock() so that the compiler can see
 * it at compile-time.
 */
#ifdef CONFIG_SMP
#define return_value_on_smp return
#else
#define return_value_on_smp
#endif
static inline int reacquire_kernel_lock(struct task_struct *task)
{
 if (unlikely(task->lock_depth >= 0))
  return_value_on_smp get_kernel_lock();
 return 0;
}
extern void __lockfunc lock_kernel(void) __acquires(kernel_lock);
extern void __lockfunc unlock_kernel(void) __releases(kernel_lock);
#else
#define lock_kernel()    do { } while(0)
#define unlock_kernel()    do { } while(0)
#define release_kernel_lock(task)  do { } while(0)
#define reacquire_kernel_lock(task)  0
#define kernel_locked()    1
#