patch-1.3.94 linux/include/asm-m68k/atomic.h

• Lines: 64
• Date: Fri Apr 5 19:33:18 1996
• Orig file: v1.3.93/linux/include/asm-m68k/atomic.h
• Orig date: Thu Jan 1 02:00:00 1970

diff -u --recursive --new-file v1.3.93/linux/include/asm-m68k/atomic.h linux/include/asm-m68k/atomic.h
@@ -0,0 +1,63 @@
+#ifndef __ARCH_M68K_ATOMIC__
+#define __ARCH_M68K_ATOMIC__
+
+/*
+ * Atomic operations that C can't guarantee us.  Useful for
+ * resource counting etc..
+ */
+
+/*
+ * We do not have SMP m68k systems, so we don't have to deal with that.
+ */
+
+/*
+ * 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 int atomic_t;
+
+static __inline__ void atomic_add(atomic_t i, atomic_t *v)
+{
+	__asm__ __volatile__(
+		"addl %1,%0"
+		:"=m" (__atomic_fool_gcc(v))
+		:"ir" (i), "m" (__atomic_fool_gcc(v)));
+}
+
+static __inline__ void atomic_sub(atomic_t i, atomic_t *v)
+{
+	__asm__ __volatile__(
+		"subl  %1,%0"
+		:"=m" (__atomic_fool_gcc(v))
+		:"ir" (i), "m" (__atomic_fool_gcc(v)));
+}
+
+static __inline__ void atomic_inc(atomic_t *v)
+{
+	__asm__ __volatile__(
+		"addql #1,%0"
+		:"=m" (__atomic_fool_gcc(v))
+		:"m" (__atomic_fool_gcc(v)));
+}
+
+static __inline__ void atomic_dec(atomic_t *v)
+{
+	__asm__ __volatile__(
+		"subql #1,%0"
+		:"=m" (__atomic_fool_gcc(v))
+		:"m" (__atomic_fool_gcc(v)));
+}
+
+static __inline__ int atomic_dec_and_test(atomic_t *v)
+{
+	__asm__ __volatile__(
+		"subql #1,%0"
+		:"=m" (__atomic_fool_gcc(v))
+		:"m" (__atomic_fool_gcc(v)));
+	return (*v <= 0);
+}
+
+#endif /* __ARCH_M68K_ATOMIC __ */