include/asm-mips64/smplock.h

   1 /*
   2  * <asm/smplock.h>
   3  *
   4  * Default SMP lock implementation
   5  */
   6 #ifndef _ASM_SMPLOCK_H
   7 #define _ASM_SMPLOCK_H
   8
   9 #include <linux/sched.h>
  10 #include <linux/interrupt.h>
  11 #include <linux/spinlock.h>
  12
  13 extern spinlock_t kernel_flag;
  14
  15 #define kernel_locked()                 spin_is_locked(&kernel_flag)
  16
  17 /*
  18  * Release global kernel lock and global interrupt lock
  19  */
  20 static __inline__ void release_kernel_lock(struct task_struct *task, int cpu)
  21 {
  22         if (task->lock_depth >= 0)
  23                 spin_unlock(&kernel_flag);
  24         release_irqlock(cpu);
  25         __sti();
  26 }
  27
  28 /*
  29  * Re-acquire the kernel lock
  30  */
  31 static __inline__ void reacquire_kernel_lock(struct task_struct *task)
  32 {
  33         if (task->lock_depth >= 0)
  34                 spin_lock(&kernel_flag);
  35 }
  36
  37 /*
  38  * Getting the big kernel lock.
  39  *
  40  * This cannot happen asynchronously,
  41  * so we only need to worry about other
  42  * CPU's.
  43  */
  44 static __inline__ void lock_kernel(void)
  45 {
  46         if (!++current->lock_depth)
  47                 spin_lock(&kernel_flag);
  48 }
  49
  50 static __inline__ void unlock_kernel(void)
  51 {
  52         if (--current->lock_depth < 0)
  53                 spin_unlock(&kernel_flag);
  54 }
  55
  56 #endif /* _ASM_SMPLOCK_H */