2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
6 * Default SMP lock implementation
8 #include <linux/interrupt.h>
9 #include <linux/spinlock.h>
11 extern spinlock_t kernel_flag;
13 #define kernel_locked() spin_is_locked(&kernel_flag)
16 * Release global kernel lock and global interrupt lock
18 #define release_kernel_lock(task, cpu) \
20 if (task->lock_depth >= 0) \
21 spin_unlock(&kernel_flag); \
22 release_irqlock(cpu); \
27 * Re-acquire the kernel lock
29 #define reacquire_kernel_lock(task) \
31 if (task->lock_depth >= 0) \
32 spin_lock(&kernel_flag); \
37 * Getting the big kernel lock.
39 * This cannot happen asynchronously,
40 * so we only need to worry about other
43 extern __inline__ void lock_kernel(void)
45 if (!++current->lock_depth)
46 spin_lock(&kernel_flag);
49 extern __inline__ void unlock_kernel(void)
51 if (--current->lock_depth < 0)
52 spin_unlock(&kernel_flag);