[PATCH] mark IS_ERR as unlikely()

It seems fair to assume that it is always unlikely that IS_ERR will return
true.

This patch changes the gcc-3.4-generated kernel text by ~500 bytes (less) so
it's fair to assume that the compiler is indeed propagating unlikeliness out
of inline functions.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/linux/err.h

 #ifndef _LINUX_ERR_H
 #define _LINUX_ERR_H
 
+#include <linux/compiler.h>
+
 #include <asm/errno.h>
 
 /*
@@ -23,7 +25,7 @@ static inline long PTR_ERR(const void *ptr)
 
 static inline long IS_ERR(const void *ptr)
 {
-	return (unsigned long)ptr > (unsigned long)-1000L;
+	return unlikely((unsigned long)ptr > (unsigned long)-1000L);
 }
 
 #endif /* _LINUX_ERR_H */