On 3/3/2016 6:14 PM, Eric Auger wrote:

Hi Sinan,
On 03/02/2016 07:34 PM, Sinan Kaya wrote:

quoted

On 2/26/2016 12:15 PM, Eric Auger wrote:

quoted

quoted

-module_init(reset ## _module_init);				\

quoted

+#define module_vfio_reset_handler(compat, acpihid, reset)		\
+MODULE_ALIAS("vfio-reset:" compat);					\

Here you need to handle alias for hid case I think

I'm wondering what happens when Compat or ACPI string is NULL.

MODULE_ALIAS("vfio-reset:" NULL)

Would the kernel like it? 

quoted

I'd rather create an alias only when the string is not NULL. Given
this is a macro, I believe it won't work. 

Indeed I think we should create an alias only for the supported case or
2 aliases if both are supported.

quoted

Can you think of any other way in the code to create the alias?

To be honest I did not find any elegant solution either. Personally I
would move the MODULE_ALIAS for compat/acpihid outside of
module_vfio_reset_handler macro, directly in the reset module. But maybe
someone will propose a better solution?

I briefly looked at this. 

#define MODULE_ALIAS(_alias) MODULE_INFO(alias, _alias)
#define MODULE_INFO(tag, info) __MODULE_INFO(tag, tag, info)

and it eventually becomes this

#define __MODULE_INFO(tag, name, info)                                    \
static const char __UNIQUE_ID(name)[]                                     \
   __used __attribute__((section(".modinfo"), unused, aligned(1)))         \
   = __stringify(tag) "=" info

Since the info is on the right side of the equation, I'm allowed to add some 
conditionals.

#define module_vfio_reset_handler(compat, acpihid, reset)		\
MODULE_ALIAS("vfio-reset:" acpihid? acpihid: compat);			\

This way, we'll create an alias with one of the provided strings.  



-- 
Sinan Kaya
Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project