patch-2.1.112 linux/include/linux/smp_lock.h

• Lines: 72
• Date: Tue Jul 28 11:23:30 1998
• Orig file: v2.1.111/linux/include/linux/smp_lock.h
• Orig date: Fri Feb 6 15:32:55 1998

diff -u --recursive --new-file v2.1.111/linux/include/linux/smp_lock.h linux/include/linux/smp_lock.h
@@ -1,6 +1,70 @@
 #ifndef __LINUX_SMPLOCK_H
 #define __LINUX_SMPLOCK_H
 
-#include <asm/smp_lock.h>
+#ifndef __SMP__
+
+#define lock_kernel()				do { } while(0)
+#define unlock_kernel()				do { } while(0)
+#define release_kernel_lock(task, cpu)		do { } while(0)
+#define reacquire_kernel_lock(task)		do { } while(0)
+
+#else
+
+#include <linux/interrupt.h>
+#include <asm/spinlock.h>
+
+extern spinlock_t kernel_flag;
+
+/*
+ * Release global kernel lock and global interrupt lock
+ */
+#define release_kernel_lock(task, cpu) \
+do { \
+	if (task->lock_depth) \
+		spin_unlock(&kernel_flag); \
+	release_irqlock(cpu); \
+	__sti(); \
+} while (0)
+
+/*
+ * Re-acquire the kernel lock
+ */
+#define reacquire_kernel_lock(task) \
+do { \
+	if (task->lock_depth) \
+		spin_lock(&kernel_flag); \
+} while (0)
+
+
+/*
+ * Getting the big kernel lock.
+ *
+ * This cannot happen asynchronously,
+ * so we only need to worry about other
+ * CPU's.
+ */
+extern __inline__ void lock_kernel(void)
+{
+	struct task_struct *tsk = current;
+	int lock_depth;
+
+	lock_depth = tsk->lock_depth;
+	tsk->lock_depth = lock_depth+1;
+	if (lock_depth)
+		spin_lock(&kernel_flag);
+}
+
+extern __inline__ void unlock_kernel(void)
+{
+	struct task_struct *tsk = current;
+	int lock_depth;
+
+	lock_depth = tsk->lock_depth-1;
+	tsk->lock_depth = lock_depth;
+	if (!lock_depth)
+		spin_unlock(&kernel_flag);
+}
+
+#endif /* __SMP__ */
 
 #endif