Re: [RFC][PATCH 1/2] kconfig: Introduce KCONFIG(), KCONFIG_BUILTIN() and KCONFIG_MODULE()

Replace the config_is_*() macros with a variant that allows for grepping
for usage of CONFIG_* options in the code. Usage:

 if (KCONFIG(CONFIG_NUMA))

or

 #if KCONFIG(CONFIG_NUMA)

The KCONFIG() macro evaluates to 1 if the argument is set (to either 'y'
or 'm'), KCONFIG_BUILTIN() and KCONFIG_MODULE() test if the respective
option is 'y' and 'm', respectively.

Signed-off-by: Michal Marek <redacted>
---
 Makefile                   |    2 +-
 include/linux/kconfig.h    |   24 +++++++++++++++
 scripts/kconfig/confdata.c |   70 ++++++++-----------------------------------
 3 files changed, 38 insertions(+), 58 deletions(-)
 create mode 100644 include/linux/kconfig.h

diff --git a/Makefile b/Makefile
index afb8e0d..bd7629b 100644
--- a/Makefile
+++ b/Makefile

@@ -360,7 +360,7 @@ CFLAGS_GCOV = -fprofile-arcs -ftest-coverage

 LINUXINCLUDE    := -I$(srctree)/arch/$(hdr-arch)/include \
                   -Iarch/$(hdr-arch)/include/generated -Iinclude \
                   $(if $(KBUILD_SRC), -I$(srctree)/include) \
-                   -include include/generated/autoconf.h
+                   -include $(srctree)/include/linux/kconfig.h

 KBUILD_CPPFLAGS := -D__KERNEL__

diff --git a/include/linux/kconfig.h b/include/linux/kconfig.h
new file mode 100644
index 0000000..fe80348
--- /dev/null
+++ b/include/linux/kconfig.h

@@ -0,0 +1,24 @@
+#ifndef __LINUX_KCONFIG_H
+#define __LINUX_KCONFIG_H
+
+#include <generated/autoconf.h>
+
+/*
+ * Evaluates to 1 if CONFIG_option is set to 'y', 0 otherwise
+ */
+#define KCONFIG_BUILTIN(option) __enabled_ ## option
+
+/*
+ * Evaluates to 1 if CONFIG_option is set to 'm', 0 otherwise
+ */
+#define KCONFIG_MODULE(option) __enabled_ ## option ## _MODULE
+
+/*
+ * Evaluates to 1 if CONFIG_option is set to 'y' or 'm', 0 otherwise
+ *
+ */
+#define KCONFIG(option) \
+       (__enabled_ ## option || __enabled_ ## option ## _MODULE)
+
+
+#endif /* __LINUX_KCONFIG_H */

diff --git a/scripts/kconfig/confdata.c b/scripts/kconfig/confdata.c
index df629ec..3bab40a 100644
--- a/scripts/kconfig/confdata.c
+++ b/scripts/kconfig/confdata.c

@@ -495,15 +495,24 @@ header_print_symbol(FILE *fp, struct symbol *sym, const char *value, void *arg)

               switch (*value) {
               case 'n':
-                       return;
+                       break;
               case 'm':
                       suffix = "_MODULE";
                       /* fall through */
               default:
-                       value = "1";
+                       fprintf(fp, "#define %s%s%s 1\n",
+                           CONFIG_, sym->name, suffix);
               }
-               fprintf(fp, "#define %s%s%s %s\n",
-                   CONFIG_, sym->name, suffix, value);
+               /*
+                * Generate the __enabled_CONFIG_* and
+                * __enabled_CONFIG_*_MODULE macros for use by the KCONFIG*()
+                * macros. The _MODULE variant is generated even for booleans
+                * so that the KCONFIG() macro works.
+                */
+               fprintf(fp, "#define __enabled_" CONFIG_ "%s %d\n",
+                               sym->name, (*value == 'y'));
+               fprintf(fp, "#define __enabled_" CONFIG_ "%s_MODULE %d\n",
+                               sym->name, (*value == 'm'));
               break;
       }
       case S_HEX: {

@@ -555,58 +564,6 @@ static struct conf_printer header_printer_cb =

 };

 /*
- * Function-style header printer
- *
- * This printer is used to generate the config_is_xxx() function-style macros
- * in `include/generated/autoconf.h'
- */
-static void
-header_function_print_symbol(FILE *fp, struct symbol *sym, const char *value, void *arg)
-{
-       int val = 0;
-       char c;
-       char *tmp, *d;
-
-       switch (sym->type) {
-       case S_BOOLEAN:
-       case S_TRISTATE:
-               break;
-       default:
-               return;
-       }
-       if (*value == 'm')
-               val = 2;
-       else if (*value == 'y')
-               val = 1;
-
-       d = strdup(CONFIG_);
-       tmp = d;
-       while ((c = *d)) {
-               *d = tolower(c);
-               d++;
-       }
-
-       fprintf(fp, "#define %sis_", tmp);
-       free(tmp);
-
-       d = strdup(sym->name);
-       tmp = d;
-       while ((c = *d)) {
-               *d = tolower(c);
-               d++;
-       }
-       fprintf(fp, "%s%s() %d\n", tmp, (val > 1) ? "_module" : "",
-                     val ? 1 : 0);
-       free(tmp);
-}
-
-static struct conf_printer header_function_printer_cb =
-{
-       .print_symbol = header_function_print_symbol,
-};
-
-
-/*
 * Tristate printer
 *
 * This printer is used when generating the `include/config/tristate.conf' file.

@@ -997,7 +954,6 @@ int conf_write_autoconf(void)

               conf_write_symbol(tristate, sym, &tristate_printer_cb, (void *)1);

               conf_write_symbol(out_h, sym, &header_printer_cb, NULL);
-               conf_write_symbol(out_h, sym, &header_function_printer_cb, NULL);
       }
       fclose(out);
       fclose(tristate);
--
1.7.6