Initial source

1 files changed, 60 insertions, 0 deletions

diff --git a/device/dev_master.h b/device/dev_master.h
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+/* 
+ * Mach Operating System
+ * Copyright (c) 1991,1990,1989 Carnegie Mellon University
+ * All Rights Reserved.
+ * 
+ * Permission to use, copy, modify and distribute this software and its
+ * documentation is hereby granted, provided that both the copyright
+ * notice and this permission notice appear in all copies of the
+ * software, derivative works or modified versions, and any portions
+ * thereof, and that both notices appear in supporting documentation.
+ * 
+ * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
+ * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
+ * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
+ * 
+ * Carnegie Mellon requests users of this software to return to
+ * 
+ *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
+ *  School of Computer Science
+ *  Carnegie Mellon University
+ *  Pittsburgh PA 15213-3890
+ * 
+ * any improvements or extensions that they make and grant Carnegie Mellon
+ * the rights to redistribute these changes.
+ */
+/*
+ *	Author: David B. Golub, Carnegie Mellon University
+ *	Date: 	11/89
+ *
+ * 	Bind an IO operation to the master CPU.
+ */
+
+#include <cpus.h>
+
+#if	NCPUS > 1
+
+#include <kern/macro_help.h>
+#include <kern/cpu_number.h>
+#include <kern/sched_prim.h>
+#include <kern/thread.h>
+#include <kern/processor.h>
+
+#define	io_grab_master() \
+	MACRO_BEGIN \
+	thread_bind(current_thread(), master_processor); \
+	if (current_processor() != master_processor) \
+	    thread_block((void (*)()) 0); \
+	MACRO_END
+
+#define	io_release_master() \
+	MACRO_BEGIN \
+	thread_bind(current_thread(), PROCESSOR_NULL); \
+	MACRO_END
+
+#else	NCPUS > 1
+
+#define	io_grab_master()
+#define	io_release_master()
+
+#endif	NCPUS > 1