Re: [PATCH v2 01/10] devm-helpers: introduce devm_mutex_init

[Christophe Leroy]

Le 07/12/2023 à 13:02, Andy Shevchenko a écrit :
> On Thu, Dec 7, 2023 at 1:23 AM George Stark <gnstark@xxxxxxxxxxxxxxxxx> wrote:
>> On 12/7/23 01:37, Christophe Leroy wrote:
>>> Le 06/12/2023 à 23:14, Christophe Leroy a écrit :
> 
> ...
> 
>>> Looking at it closer, I have the feeling that you want to do similar to
>>> devm_gpio_request() in linux/gpio.h :
>>>
>>> In linux/mutex.h, add a prototype for devm_mutex_init() when
>>> CONFIG_DEBUG_MUTEXES is defined and an empty static inline otherwise.
>>> Then define devm_mutex_init() in kernel/locking/mutex-debug.c
>>
>> Yes, this would be almost perfect decision. BTW just as in linux/gpio.h
>> we wouldn't have to include whole "linux/device.h" into mutex.h, only
>> add forward declaration of struct device;
> 
> In case you place it into a C-file. Otherwise you need a header for
> the API and that is not acceptable for mutex.h.
> 

Right, that's the reason why I'm suggesting to define devm_mutex_init() 
in kernel/locking/mutex-debug.c.

In linux/mutex.h, you define a stub for when CONFIG_DEBUG_MUTEXES is not 
set, and the prototype of devm_mutex_init() when CONFIG_DEBUG_MUTEXES is 
set.