patch-2.3.48 linux/include/asm-mips64/atomic.h

• Lines: 125
• Date: Thu Feb 24 22:53:35 2000
• Orig file: v2.3.47/linux/include/asm-mips64/atomic.h
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.3.47/linux/include/asm-mips64/atomic.h linux/include/asm-mips64/atomic.h
@@ -0,0 +1,124 @@
+/* $Id: atomic.h,v 1.1 1999/08/18 23:37:50 ralf Exp $
+ *
+ * Atomic operations that C can't guarantee us.  Useful for
+ * resource counting etc..
+ *
+ * But use these as seldom as possible since they are much more slower
+ * than regular operations.
+ *
+ * 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.
+ *
+ * Copyright (C) 1996, 1997, 1999 by Ralf Baechle
+ */
+#ifndef _ASM_ATOMIC_H
+#define _ASM_ATOMIC_H
+
+#include <asm/sgidefs.h>
+
+#ifdef __SMP__
+typedef struct { volatile int counter; } atomic_t;
+#else
+typedef struct { int counter; } atomic_t;
+#endif
+
+#ifdef __KERNEL__
+#define ATOMIC_INIT(i)    { (i) }
+
+#define atomic_read(v)	((v)->counter)
+#define atomic_set(v,i)	((v)->counter = (i))
+
+/*
+ * Make sure gcc doesn't try to be clever and move things around
+ * on us. We need to use _exactly_ the address the user gave us,
+ * not some alias that contains the same information.
+ */
+#define __atomic_fool_gcc(x) (*(volatile struct { int a[100]; } *)x)
+
+extern __inline__ void atomic_add(int i, volatile atomic_t * v)
+{
+	unsigned long temp;
+
+	__asm__ __volatile__(
+		"1:\tll\t%0,%1\n\t"
+		"addu\t%0,%2\n\t"
+		"sc\t%0,%1\n\t"
+		"beqz\t%0,1b"
+		:"=&r" (temp),
+		 "=m" (__atomic_fool_gcc(v))
+		:"Ir" (i),
+		 "m" (__atomic_fool_gcc(v)));
+}
+
+extern __inline__ void atomic_sub(int i, volatile atomic_t * v)
+{
+	unsigned long temp;
+
+	__asm__ __volatile__(
+		"1:\tll\t%0,%1\n\t"
+		"subu\t%0,%2\n\t"
+		"sc\t%0,%1\n\t"
+		"beqz\t%0,1b"
+		:"=&r" (temp),
+		 "=m" (__atomic_fool_gcc(v))
+		:"Ir" (i),
+		 "m" (__atomic_fool_gcc(v)));
+}
+
+/*
+ * Same as above, but return the result value
+ */
+extern __inline__ int atomic_add_return(int i, atomic_t * v)
+{
+	unsigned long temp, result;
+
+	__asm__ __volatile__(
+		".set\tnoreorder\n"
+		"1:\tll\t%1,%2\n\t"
+		"addu\t%0,%1,%3\n\t"
+		"sc\t%0,%2\n\t"
+		"beqz\t%0,1b\n\t"
+		"addu\t%0,%1,%3\n\t"
+		".set\treorder"
+		:"=&r" (result),
+		 "=&r" (temp),
+		 "=m" (__atomic_fool_gcc(v))
+		:"Ir" (i),
+		 "m" (__atomic_fool_gcc(v)));
+
+	return result;
+}
+
+extern __inline__ int atomic_sub_return(int i, atomic_t * v)
+{
+	unsigned long temp, result;
+
+	__asm__ __volatile__(
+		".set\tnoreorder\n"
+		"1:\tll\t%1,%2\n\t"
+		"subu\t%0,%1,%3\n\t"
+		"sc\t%0,%2\n\t"
+		"beqz\t%0,1b\n\t"
+		"subu\t%0,%1,%3\n\t"
+		".set\treorder"
+		:"=&r" (result),
+		 "=&r" (temp),
+		 "=m" (__atomic_fool_gcc(v))
+		:"Ir" (i),
+		 "m" (__atomic_fool_gcc(v)));
+
+	return result;
+}
+
+#define atomic_dec_return(v) atomic_sub_return(1,(v))
+#define atomic_inc_return(v) atomic_add_return(1,(v))
+
+#define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0)
+#define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0)
+
+#define atomic_inc(v) atomic_add(1,(v))
+#define atomic_dec(v) atomic_sub(1,(v))
+#endif /* defined(__KERNEL__) */
+
+#endif /* _ASM_ATOMIC_H */