patch-2.1.9 linux/include/asm-sparc/atomic.h

• Lines: 150
• Date: Sat Nov 9 21:39:32 1996
• Orig file: v2.1.8/linux/include/asm-sparc/atomic.h
• Orig date: Sun Apr 21 12:30:33 1996

diff -u --recursive --new-file v2.1.8/linux/include/asm-sparc/atomic.h linux/include/asm-sparc/atomic.h
@@ -6,55 +6,110 @@
 #ifndef __ARCH_SPARC_ATOMIC__
 #define __ARCH_SPARC_ATOMIC__
 
-#ifdef __SMP__
-#include <asm/smp.h>
-#include <asm/smp_lock.h>
-#endif
-
 typedef int atomic_t;
 
+#ifdef __KERNEL__
+#include <asm/system.h>
+#include <asm/psr.h>
+
+/*
+ * 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)
+
 static __inline__ void atomic_add(atomic_t i, atomic_t *v)
 {
-	unsigned long flags;
-
-	save_flags(flags); cli();
-	*v += i;
-	restore_flags(flags);
+	__asm__ __volatile__("
+	rd	%%psr, %%g2
+	andcc	%%g2, %2, %%g0
+	be,a	1f
+	 wr	%%g2, %2, %%psr
+1:	ld	[%0], %%g3
+	add	%%g3, %1, %%g3
+	andcc	%%g2, %2, %%g0
+	st	%%g3, [%0]
+	be,a	1f
+	 wr	%%g2, 0x0, %%psr
+1:	nop; nop;
+        "
+        : : "r" (__atomic_fool_gcc(v)), "r" (i), "i" (PSR_PIL)
+        : "g2", "g3");
 }
 
 static __inline__ void atomic_sub(atomic_t i, atomic_t *v)
 {
-	unsigned long flags;
-
-	save_flags(flags); cli();
-	*v -= i;
-	restore_flags(flags);
-}
+	__asm__ __volatile__("
+	rd	%%psr, %%g2
+	andcc	%%g2, %2, %%g0
+	be,a	1f
+	 wr	%%g2, %2, %%psr
+1:	ld	[%0], %%g3
+	sub	%%g3, %1, %%g3
+	andcc	%%g2, %2, %%g0
+	st	%%g3, [%0]
+	be,a	1f
+	 wr	%%g2, 0x0, %%psr
+1:       nop; nop;
+        "
+        : : "r" (__atomic_fool_gcc(v)), "r" (i), "i" (PSR_PIL)
+        : "g2", "g3");
+}
+
+static __inline__ int atomic_add_return(atomic_t i, atomic_t *v)
+{
+	__asm__ __volatile__("
+	rd	%%psr, %%g2
+	andcc	%%g2, %3, %%g0
+	be,a	1f
+	 wr	%%g2, %3, %%psr
+1:	ld	[%1], %%g3
+	add	%%g3, %2, %0
+	andcc	%%g2, %3, %%g0
+	st	%0, [%1]
+	be,a	1f
+	 wr	%%g2, 0x0, %%psr
+1:	nop; nop;
+        "
+        : "=&r" (i)
+        : "r" (__atomic_fool_gcc(v)), "0" (i), "i" (PSR_PIL)
+        : "g2", "g3");
+
+	return i;
+}
+
+static __inline__ int atomic_sub_return(atomic_t i, atomic_t *v)
+{
+	__asm__ __volatile__("
+	rd	%%psr, %%g2
+	andcc	%%g2, %3, %%g0
+	be,a	1f
+	 wr	%%g2, %3, %%psr
+1:	ld	[%1], %%g3
+	sub	%%g3, %2, %0
+	andcc	%%g2, %3, %%g0
+	st	%0, [%1]
+	be,a	1f
+	 wr	%%g2, 0x0, %%psr
+1:	nop; nop;
+        "
+        : "=&r" (i)
+        : "r" (__atomic_fool_gcc(v)), "0" (i), "i" (PSR_PIL)
+        : "g2", "g3");
+
+	return i;
+}
+
+#define atomic_dec_return(v) atomic_sub_return(1,(v))
+#define atomic_inc_return(v) atomic_add_return(1,(v))
 
-static __inline__ int atomic_sub_and_test(atomic_t i, atomic_t *v)
-{
-	unsigned long flags, result;
+#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)
 
-	save_flags(flags); cli();
-	*v -= i;
-	result = (*v == 0);
-	restore_flags(flags);
-	return result;
-}
+#define atomic_inc(v) atomic_add(1,(v))
+#define atomic_dec(v) atomic_sub(1,(v))
 
-static __inline__ void atomic_inc(atomic_t *v)
-{
-	atomic_add(1, v);
-}
-
-static __inline__ void atomic_dec(atomic_t *v)
-{
-	atomic_sub(1, v);
-}
-
-static __inline__ int atomic_dec_and_test(atomic_t *v)
-{
-	return atomic_sub_and_test(1, v);
-}
+#endif /* !(__KERNEL__) */
 
 #endif /* !(__ARCH_SPARC_ATOMIC__) */