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#ifndef __LINUX_SMPLOCK_H
#define __LINUX_SMPLOCK_H
#include <linux/config.h>
#ifdef CONFIG_LOCK_KERNEL
#include <linux/sched.h>
#include <linux/spinlock.h>
#define kernel_locked() (current->lock_depth >= 0)
extern int __lockfunc __reacquire_kernel_lock(void);
extern void __lockfunc __release_kernel_lock(void);
/*
* Release/re-acquire global kernel lock for the scheduler
*/
#define release_kernel_lock(tsk) do { \
if (unlikely((tsk)->lock_depth >= 0)) \
__release_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.
*/
#if defined(CONFIG_SMP) && !defined(CONFIG_PREEMPT_BKL)
# 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 __reacquire_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
#endif /* CONFIG_LOCK_KERNEL */
#endif /* __LINUX_SMPLOCK_H */
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