diff mbox

[27/74] lto: Mark EXPORT_SYMBOL symbols __visible

Message ID 1345345030-22211-28-git-send-email-andi@firstfloor.org (mailing list archive)
State New, archived
Headers show

Commit Message

Andi Kleen Aug. 19, 2012, 2:56 a.m. UTC 
From: Andi Kleen <ak@linux.intel.com>

Signed-off-by: Andi Kleen <ak@linux.intel.com>
---
 include/linux/export.h |   14 ++++++++------
 1 files changed, 8 insertions(+), 6 deletions(-)

Comments

Rusty Russell Aug. 20, 2012, 6:54 a.m. UTC | #1 
On Sat, 18 Aug 2012 19:56:23 -0700, Andi Kleen <andi@firstfloor.org> wrote:
> @@ -78,11 +78,13 @@ extern struct module __this_module;
>  
>  #else /* !CONFIG_MODULES... */
>  
> -#define EXPORT_SYMBOL(sym)
> -#define EXPORT_SYMBOL_GPL(sym)
> -#define EXPORT_SYMBOL_GPL_FUTURE(sym)
> -#define EXPORT_UNUSED_SYMBOL(sym)
> -#define EXPORT_UNUSED_SYMBOL_GPL(sym)
> +/* Even without modules keep the __visible side effect */
> +
> +#define EXPORT_SYMBOL(sym) extern typeof(sym) sym __visible
> +#define EXPORT_SYMBOL_GPL(sym) extern typeof(sym) sym __visible
> +#define EXPORT_SYMBOL_GPL_FUTURE(sym) extern typeof(sym) sym __visible
> +#define EXPORT_UNUSED_SYMBOL(sym) extern typeof(sym) sym __visible
> +#define EXPORT_UNUSED_SYMBOL_GPL(sym) extern typeof(sym) sym __visible
>  
>  #endif /* CONFIG_MODULES */

Really, why?  Seems like a win to have them eliminated if unused.

Naively, I would think many cases of __visible should be #ifdef
CONFIG_MODULES.  What am I missing?

Thanks,
Rusty.
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Andi Kleen Aug. 20, 2012, 9:49 a.m. UTC | #2 
> Really, why?  Seems like a win to have them eliminated if unused.
> 
> Naively, I would think many cases of __visible should be #ifdef
> CONFIG_MODULES.  What am I missing?

It worked around some problem I forgot now :)

You're right it shouldn't be needed in theory for !MODULES. I'll double
check.

-Andi
diff mbox

Patch

diff --git a/include/linux/export.h b/include/linux/export.h
index 696c0f4..784617e 100644
--- a/include/linux/export.h
+++ b/include/linux/export.h
@@ -47,7 +47,7 @@  extern struct module __this_module;
 
 /* For every exported symbol, place a struct in the __ksymtab section */
 #define __EXPORT_SYMBOL(sym, sec)				\
-	extern typeof(sym) sym;					\
+	extern typeof(sym) sym __visible;			\
 	__CRC_SYMBOL(sym, sec)					\
 	static const char __kstrtab_##sym[]			\
 	__attribute__((section("__ksymtab_strings"), aligned(1))) \
@@ -78,11 +78,13 @@  extern struct module __this_module;
 
 #else /* !CONFIG_MODULES... */
 
-#define EXPORT_SYMBOL(sym)
-#define EXPORT_SYMBOL_GPL(sym)
-#define EXPORT_SYMBOL_GPL_FUTURE(sym)
-#define EXPORT_UNUSED_SYMBOL(sym)
-#define EXPORT_UNUSED_SYMBOL_GPL(sym)
+/* Even without modules keep the __visible side effect */
+
+#define EXPORT_SYMBOL(sym) extern typeof(sym) sym __visible
+#define EXPORT_SYMBOL_GPL(sym) extern typeof(sym) sym __visible
+#define EXPORT_SYMBOL_GPL_FUTURE(sym) extern typeof(sym) sym __visible
+#define EXPORT_UNUSED_SYMBOL(sym) extern typeof(sym) sym __visible
+#define EXPORT_UNUSED_SYMBOL_GPL(sym) extern typeof(sym) sym __visible
 
 #endif /* CONFIG_MODULES */