Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild

[cascardo/linux.git] / include / linux / init.h

diff --git a/include/linux/init.h b/include/linux/init.h
index 5a3321a..024a0b5 100644 (file)
--- a/include/linux/init.h
+++ b/include/linux/init.h
@@ -139,24 +139,8 @@ extern bool initcall_debug;
 
 #ifndef __ASSEMBLY__
 
-#ifdef CONFIG_LTO
-/* Work around a LTO gcc problem: when there is no reference to a variable
- * in a module it will be moved to the end of the program. This causes
- * reordering of initcalls which the kernel does not like.
- * Add a dummy reference function to avoid this. The function is
- * deleted by the linker.
- */
-#define LTO_REFERENCE_INITCALL(x) \
-       ; /* yes this is needed */                      \
-       static __used __exit void *reference_##x(void)  \
-       {                                               \
-               return &x;                              \
-       }
-#else
-#define LTO_REFERENCE_INITCALL(x)
-#endif
-
-/* initcalls are now grouped by functionality into separate 
+/*
+ * initcalls are now grouped by functionality into separate
  * subsections. Ordering inside the subsections is determined
  * by link order. 
  * For backwards compatibility, initcall() puts the call in 
@@ -164,12 +148,16 @@ extern bool initcall_debug;
  *
  * The `id' arg to __define_initcall() is needed so that multiple initcalls
  * can point at the same handler without causing duplicate-symbol build errors.
+ *
+ * Initcalls are run by placing pointers in initcall sections that the
+ * kernel iterates at runtime. The linker can do dead code / data elimination
+ * and remove that completely, so the initcall sections have to be marked
+ * as KEEP() in the linker script.
  */
 
 #define __define_initcall(fn, id) \
        static initcall_t __initcall_##fn##id __used \
-       __attribute__((__section__(".initcall" #id ".init"))) = fn; \
-       LTO_REFERENCE_INITCALL(__initcall_##fn##id)
+       __attribute__((__section__(".initcall" #id ".init"))) = fn;
 
 /*
  * Early initcalls run before initializing SMP.
@@ -205,15 +193,15 @@ extern bool initcall_debug;
 
 #define __initcall(fn) device_initcall(fn)
 
-#define __exitcall(fn) \
+#define __exitcall(fn)                                         \
        static exitcall_t __exitcall_##fn __exit_call = fn
 
-#define console_initcall(fn) \
-       static initcall_t __initcall_##fn \
+#define console_initcall(fn)                                   \
+       static initcall_t __initcall_##fn                       \
        __used __section(.con_initcall.init) = fn
 
-#define security_initcall(fn) \
-       static initcall_t __initcall_##fn \
+#define security_initcall(fn)                                  \
+       static initcall_t __initcall_##fn                       \
        __used __section(.security_initcall.init) = fn
 
 struct obs_kernel_param {