export.h: allow for per-symbol configurable EXPORT_SYMBOL()

[deliverable/linux.git] / include / linux / export.h

diff --git a/include/linux/export.h b/include/linux/export.h
index 96e45ea463e71e19575d1db97da22a0eb72d05c8..77afdb2a250653f77506ed5308649ae703163936 100644 (file)
--- a/include/linux/export.h
+++ b/include/linux/export.h
@@ -38,7 +38,7 @@ extern struct module __this_module;
 
 #ifdef CONFIG_MODULES
 
-#ifndef __GENKSYMS__
+#if defined(__KERNEL__) && !defined(__GENKSYMS__)
 #ifdef CONFIG_MODVERSIONS
 /* Mark the CRC weak since genksyms apparently decides not to
  * generate a checksums for some symbols */
@@ -53,7 +53,7 @@ extern struct module __this_module;
 #endif
 
 /* For every exported symbol, place a struct in the __ksymtab section */
-#define __EXPORT_SYMBOL(sym, sec)                              \
+#define ___EXPORT_SYMBOL(sym, sec)                             \
        extern typeof(sym) sym;                                 \
        __CRC_SYMBOL(sym, sec)                                  \
        static const char __kstrtab_##sym[]                     \
@@ -65,6 +65,24 @@ extern struct module __this_module;
        __attribute__((section("___ksymtab" sec "+" #sym), unused))     \
        = { (unsigned long)&sym, __kstrtab_##sym }
 
+#ifdef CONFIG_TRIM_UNUSED_KSYMS
+
+#include <linux/kconfig.h>
+#include <generated/autoksyms.h>
+
+#define __EXPORT_SYMBOL(sym, sec)                              \
+       __cond_export_sym(sym, sec, config_enabled(__KSYM_##sym))
+#define __cond_export_sym(sym, sec, conf)                      \
+       ___cond_export_sym(sym, sec, conf)
+#define ___cond_export_sym(sym, sec, enabled)                  \
+       __cond_export_sym_##enabled(sym, sec)
+#define __cond_export_sym_1(sym, sec) ___EXPORT_SYMBOL(sym, sec)
+#define __cond_export_sym_0(sym, sec) /* nothing */
+
+#else
+#define __EXPORT_SYMBOL ___EXPORT_SYMBOL
+#endif
+
 #define EXPORT_SYMBOL(sym)                                     \
        __EXPORT_SYMBOL(sym, "")