X-Git-Url: https://git.subgeniuskitty.com/unix-history/.git/blobdiff_plain/ed554bc5e4201344d7eaad78263566e79428759c..fd88f5c5678c80ff5e338adc372d28a52ad20530:/usr/src/sys/news3400/include/param.h

diff --git a/usr/src/sys/news3400/include/param.h b/usr/src/sys/news3400/include/param.h
index cf08d90d25..75dee5cfac 100644
--- a/usr/src/sys/news3400/include/param.h
+++ b/usr/src/sys/news3400/include/param.h
@@ -37,13 +37,14 @@
  *
  * from: Utah $Hdr: machparam.h 1.11 89/08/14$
  *
- *	@(#)param.h	8.1 (Berkeley) 6/11/93
+ *	@(#)param.h	8.3 (Berkeley) 5/14/95
  */
 
 /*
  * Machine dependent constants for DEC Station 3100.
  */
 #define	MACHINE	"news3400"
+#define NCPUS 1
 #define COFF
 
 /*
@@ -121,9 +122,9 @@
 #define	btoc(x)	(((unsigned)(x)+(NBPG-1))>>PGSHIFT)
 
 #define	btodb(bytes)	 		/* calculates (bytes / DEV_BSIZE) */ \
-	((unsigned)(bytes) >> DEV_BSHIFT)
+	((bytes) >> DEV_BSHIFT)
 #define	dbtob(db)			/* calculates (db * DEV_BSIZE) */ \
-	((unsigned)(db) << DEV_BSHIFT)
+	((db) << DEV_BSHIFT)
 
 /*
  * Map a ``block device block'' to a file system block.
@@ -212,3 +213,62 @@ extern char	*intrnames[];
 #define INTR_RENDER	44
 
 #define	NINTRSLOT	45		/* # of intrcnt[] slot */
+
+#ifndef _SIMPLELOCK_H_
+#define _SIMPLELOCK_H_
+/*
+ * A simple spin lock.
+ *
+ * This structure only sets one bit of data, but is sized based on the
+ * minimum word size that can be operated on by the hardware test-and-set
+ * instruction. It is only needed for multiprocessors, as uniprocessors
+ * will always run to completion or a sleep. It is an error to hold one
+ * of these locks while a process is sleeping.
+ */
+struct simplelock {
+	int	lock_data;
+};
+
+#if !defined(DEBUG) && NCPUS > 1
+/*
+ * The simple-lock routines are the primitives out of which the lock
+ * package is built. The machine-dependent code must implement an
+ * atomic test_and_set operation that indivisibly sets the simple lock
+ * to non-zero and returns its old value. It also assumes that the
+ * setting of the lock to zero below is indivisible. Simple locks may
+ * only be used for exclusive locks.
+ */
+static __inline void
+simple_lock_init(lkp)
+	struct simplelock *lkp;
+{
+
+	lkp->lock_data = 0;
+}
+
+static __inline void
+simple_lock(lkp)
+	__volatile struct simplelock *lkp;
+{
+
+	while (test_and_set(&lkp->lock_data))
+		continue;
+}
+
+static __inline int
+simple_lock_try(lkp)
+	__volatile struct simplelock *lkp;
+{
+
+	return (!test_and_set(&lkp->lock_data))
+}
+
+static __inline void
+simple_unlock(lkp)
+	__volatile struct simplelock *lkp;
+{
+
+	lkp->lock_data = 0;
+}
+#endif /* NCPUS > 1 */
+#endif /* !_SIMPLELOCK_H_ */