kconfig.h: remove config_enabled() macro

The use of config_enabled() is ambiguous.  For config options,
IS_ENABLED(), IS_REACHABLE(), etc.  will make intention clearer.
Sometimes config_enabled() has been used for non-config options because
it is useful to check whether the given symbol is defined or not.

I have been tackling on deprecating config_enabled(), and now is the
time to finish this work.

Some new users have appeared for v4.9-rc1, but it is trivial to replace
them:

 - arch/x86/mm/kaslr.c
  replace config_enabled() with IS_ENABLED() because
  CONFIG_X86_ESPFIX64 and CONFIG_EFI are boolean.

 - include/asm-generic/export.h
  replace config_enabled() with __is_defined().

Then, config_enabled() can be removed now.

Going forward, please use IS_ENABLED(), IS_REACHABLE(), etc. for config
options, and __is_defined() for non-config symbols.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Masahiro Yamada <[email protected]>
Acked-by: Ingo Molnar <[email protected]>
Acked-by: Nicolas Pitre <[email protected]>
Cc: Peter Oberparleiter <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Michal Marek <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Thomas Garnier <[email protected]>
Cc: Paul Bolle <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

arch/x86/mm/kaslr.c

@@ -104,10 +104,10 @@ void __init kernel_randomize_memory(void)
 	 * consistent with the vaddr_start/vaddr_end variables.
 	 */
 	BUILD_BUG_ON(vaddr_start >= vaddr_end);
-	BUILD_BUG_ON(config_enabled(CONFIG_X86_ESPFIX64) &&
+	BUILD_BUG_ON(IS_ENABLED(CONFIG_X86_ESPFIX64) &&
 		     vaddr_end >= EFI_VA_START);
-	BUILD_BUG_ON((config_enabled(CONFIG_X86_ESPFIX64) ||
-		      config_enabled(CONFIG_EFI)) &&
+	BUILD_BUG_ON((IS_ENABLED(CONFIG_X86_ESPFIX64) ||
+		      IS_ENABLED(CONFIG_EFI)) &&
 		     vaddr_end >= __START_KERNEL_map);
 	BUILD_BUG_ON(vaddr_end > __START_KERNEL_map);
 

include/asm-generic/export.h

@@ -70,7 +70,7 @@ KSYM(__kcrctab_\name):
 #include <generated/autoksyms.h>
 
 #define __EXPORT_SYMBOL(sym, val, sec)				\
-	__cond_export_sym(sym, val, sec, config_enabled(__KSYM_##sym))
+	__cond_export_sym(sym, val, sec, __is_defined(__KSYM_##sym))
 #define __cond_export_sym(sym, val, sec, conf)			\
 	___cond_export_sym(sym, val, sec, conf)
 #define ___cond_export_sym(sym, val, sec, enabled)		\

include/linux/kconfig.h

@@ -31,7 +31,6 @@
  * When CONFIG_BOOGER is not defined, we generate a (... 1, 0) pair, and when
  * the last step cherry picks the 2nd arg, we get a zero.
  */
-#define config_enabled(cfg)		___is_defined(cfg)
 #define __is_defined(x)			___is_defined(x)
 #define ___is_defined(val)		____is_defined(__ARG_PLACEHOLDER_##val)
 #define ____is_defined(arg1_or_junk)	__take_second_arg(arg1_or_junk 1, 0)
@@ -41,13 +40,13 @@
  * otherwise. For boolean options, this is equivalent to
  * IS_ENABLED(CONFIG_FOO).
  */
-#define IS_BUILTIN(option) config_enabled(option)
+#define IS_BUILTIN(option) __is_defined(option)
 
 /*
  * IS_MODULE(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'm', 0
  * otherwise.
  */
-#define IS_MODULE(option) config_enabled(option##_MODULE)
+#define IS_MODULE(option) __is_defined(option##_MODULE)
 
 /*
  * IS_REACHABLE(CONFIG_FOO) evaluates to 1 if the currently compiled