patch-2.3.23 linux/include/asm-sh/smplock.h

• Lines: 71
• Date: Mon Oct 18 11:16:13 1999
• Orig file: v2.3.22/linux/include/asm-sh/smplock.h
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.3.22/linux/include/asm-sh/smplock.h linux/include/asm-sh/smplock.h
@@ -0,0 +1,70 @@
+#ifndef __ASM_SH_SMPLOCK_H
+#define __ASM_SH_SMPLOCK_H
+
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef __SMP__
+
+#define lock_kernel()				do { } while(0)
+#define unlock_kernel()				do { } while(0)
+#define release_kernel_lock(task, cpu, depth)	((depth) = 1)
+#define reacquire_kernel_lock(task, cpu, depth)	do { } while(0)
+
+#else
+
+#error "We do not support SMP on SH yet"
+/*
+ * Default SMP lock implementation
+ */
+
+#include <linux/interrupt.h>
+#include <asm/spinlock.h>
+
+extern spinlock_t kernel_flag;
+
+/*
+ * 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)
+{
+	if (!++current->lock_depth)
+		spin_lock(&kernel_flag);
+}
+
+extern __inline__ void unlock_kernel(void)
+{
+	if (--current->lock_depth < 0)
+		spin_unlock(&kernel_flag);
+}
+
+/*
+ * Release global kernel lock and global interrupt lock
+ */
+#define release_kernel_lock(task, cpu) \
+do { \
+	if (task->lock_depth >= 0) \
+		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 >= 0) \
+		spin_lock(&kernel_flag); \
+} while (0)
+
+#endif /* __SMP__ */
+
+#endif /* __ASM_SH_SMPLOCK_H */