patch-2.4.2 linux/include/asm-cris/atomic.h

• Lines: 143
• Date: Thu Feb 8 16:32:44 2001
• Orig file: v2.4.1/linux/include/asm-cris/atomic.h
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.1/linux/include/asm-cris/atomic.h linux/include/asm-cris/atomic.h
@@ -0,0 +1,142 @@
+/* $Id: atomic.h,v 1.2 2000/07/13 16:51:57 bjornw Exp $ */
+
+#ifndef __ASM_CRIS_ATOMIC__
+#define __ASM_CRIS_ATOMIC__
+
+#include <asm/system.h>
+
+/*
+ * Atomic operations that C can't guarantee us.  Useful for
+ * resource counting etc..
+ */
+
+/*
+ * 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) (*(struct { int a[100]; } *)x)
+
+typedef struct { int counter; } atomic_t;
+
+#define ATOMIC_INIT(i)  { (i) }
+
+#define atomic_read(v) ((v)->counter)
+#define atomic_set(v,i) (((v)->counter) = (i))
+
+/* These should be written in asm but we do it in C for now. */
+
+static __inline__ void atomic_add(int i, volatile atomic_t *v)
+{
+	unsigned long flags;
+	save_flags(flags);
+	cli();
+	v->counter += i;
+	restore_flags(flags);
+}
+
+static __inline__ void atomic_sub(int i, volatile atomic_t *v)
+{
+	unsigned long flags;
+	save_flags(flags);
+	cli();
+	v->counter -= i;
+	restore_flags(flags);
+}
+
+static __inline__ int atomic_add_return(int i, volatile atomic_t *v)
+{
+	unsigned long flags;
+	int retval;
+	save_flags(flags);
+	cli();
+	retval = (v->counter += i);
+	restore_flags(flags);
+	return retval;
+}
+
+static __inline__ int atomic_sub_return(int i, volatile atomic_t *v)
+{
+	unsigned long flags;
+	int retval;
+	save_flags(flags);
+	cli();
+	retval = (v->counter -= i);
+	restore_flags(flags);
+	return retval;
+}
+
+static __inline__ int atomic_sub_and_test(int i, volatile atomic_t *v)
+{
+	int retval;
+	unsigned long flags;
+	save_flags(flags);
+	cli();
+	retval = (v->counter -= i) == 0;
+	restore_flags(flags);
+	return retval;
+}
+
+static __inline__ void atomic_inc(volatile atomic_t *v)
+{
+	unsigned long flags;
+	save_flags(flags);
+	cli();
+	(v->counter)++;
+	restore_flags(flags);
+}
+
+static __inline__ void atomic_dec(volatile atomic_t *v)
+{
+	unsigned long flags;
+	save_flags(flags);
+	cli();
+	(v->counter)--;
+	restore_flags(flags);
+}
+
+static __inline__ int atomic_inc_return(volatile atomic_t *v)
+{
+	unsigned long flags;
+	int retval;
+	save_flags(flags);
+	cli();
+	retval = (v->counter)++;
+	restore_flags(flags);
+	return retval;
+}
+
+static __inline__ int atomic_dec_return(volatile atomic_t *v)
+{
+	unsigned long flags;
+	int retval;
+	save_flags(flags);
+	cli();
+	retval = (v->counter)--;
+	restore_flags(flags);
+	return retval;
+}
+static __inline__ int atomic_dec_and_test(volatile atomic_t *v)
+{
+	int retval;
+	unsigned long flags;
+	save_flags(flags);
+	cli();
+	retval = --(v->counter) == 0;
+	restore_flags(flags);
+	return retval;
+}
+
+static __inline__ int atomic_inc_and_test(volatile atomic_t *v)
+{
+	int retval;
+	unsigned long flags;
+	save_flags(flags);
+	cli();
+	retval = ++(v->counter) == 0;
+	restore_flags(flags);
+	return retval;
+}
+
+#endif