include/asm-sparc64/smplock.h

   1 /*
   2  * <asm/smplock.h>
   3  *
   4  * Default SMP lock implementation
   5  */
   6 #include <linux/sched.h>
   7 #include <linux/interrupt.h>
   8 #include <linux/spinlock.h>
   9
  10 extern spinlock_t kernel_flag;
  11
  12 #define kernel_locked()                 \
  13         (spin_is_locked(&kernel_flag) &&\
  14          (current->lock_depth >= 0))
  15
  16 /*
  17  * Release global kernel lock and global interrupt lock
  18  */
  19 #define release_kernel_lock(task, cpu) \
  20 do { \
  21         if (task->lock_depth >= 0) \
  22                 spin_unlock(&kernel_flag); \
  23         release_irqlock(cpu); \
  24         __sti(); \
  25 } while (0)
  26
  27 /*
  28  * Re-acquire the kernel lock
  29  */
  30 #define reacquire_kernel_lock(task) \
  31 do { \
  32         if (task->lock_depth >= 0) \
  33                 spin_lock(&kernel_flag); \
  34 } while (0)
  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 #define lock_kernel() \
  45 do { \
  46         if (!++current->lock_depth) \
  47                 spin_lock(&kernel_flag); \
  48 } while(0)
  49
  50 #define unlock_kernel() \
  51 do { \
  52         if (--current->lock_depth < 0) \
  53                 spin_unlock(&kernel_flag); \
  54 } while(0)