include/asm-ia64/smplock.h

   1 /*
   2  * <asm/smplock.h>
   3  *
   4  * Default SMP lock implementation
   5  */
   6 #include <linux/interrupt.h>
   7 #include <linux/spinlock.h>
   8 #include <linux/sched.h>
   9
  10 #include <asm/current.h>
  11 #include <asm/hardirq.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
  21 release_kernel_lock(struct task_struct *task, int cpu)
  22 {
  23         if (task->lock_depth >= 0)
  24                 spin_unlock(&kernel_flag);
  25         release_irqlock(cpu);
  26         __sti();
  27 }
  28
  29 /*
  30  * Re-acquire the kernel lock
  31  */
  32 static __inline__ void
  33 reacquire_kernel_lock(struct task_struct *task)
  34 {
  35         if (task->lock_depth >= 0)
  36                 spin_lock(&kernel_flag);
  37 }
  38
  39 /*
  40  * Getting the big kernel lock.
  41  *
  42  * This cannot happen asynchronously,
  43  * so we only need to worry about other
  44  * CPU's.
  45  */
  46 static __inline__ void
  47 lock_kernel(void)
  48 {
  49         if (!++current->lock_depth)
  50                 spin_lock(&kernel_flag);
  51 }
  52
  53 static __inline__ void
  54 unlock_kernel(void)
  55 {
  56         if (--current->lock_depth < 0)
  57                 spin_unlock(&kernel_flag);
  58 }