[PATCH 1/2] nptl: Remove __ASSUME_SET_ROBUST_LIST

[Adhemerval Zanella]

On 19/04/2017 15:09, Florian Weimer wrote:
> On 04/19/2017 07:38 PM, Adhemerval Zanella wrote:
>> On Wed, Apr 19, 2017 at 12:28 PM, Florian Weimer <fweimer@redhat.com> wrote:
>>> On 04/19/2017 04:17 PM, Adhemerval Zanella wrote:
>>>>
>>>> The problem is kernel supports for some architecture depends of kernel
>>>> config
>>>> and the underlying hardware revision/model.
>>>
>>>
>>> I understand that.  But I have seen a lot of use of robust mutexes lately,
>>> and I'm sure these developers aren't aware that the mutexes aren't portable
>>> across GNU/Linux (the Linux architecture subset supported by glibc).
>>>
>>> I expect it's like the missing accept4 system call—you need to provide the
>>> set_robust_list system call in the kernel if you want to a working, modern
>>> system.
>>
>> But my point is with current minimum supported kernel version for some
>> architectures
>> we can't simple assume set_robust_list support and even bumping minimum kernel
>> version for some architectures also do not solve the issue (on mips
>> for instance).
> 
> Hmm, maybe you are right, and we have to keep things this way for now.
> 
> But I don't like that your patch reintroduces the conditional code.  You could use
> 
> #define __set_robust_list_avail 1
> 
> for the __ASSUME_SET_ROBUST_LIST case to reduce clutter, and let GCC do the rest.

Rechecking what you meant, I am not following you here: the idea is to have
__set_robust_list_avail being a runtime variable and get rid of the _ASSUME
define. How using a define would help in this way?