[cfe-users] RFC v4: Re: cacheflush.2

[Alejandro Colomar (man-pages) via cfe-users]

I forgot to add a junk to the text.

v4:

NOTES
       Unless  you  need  the finer grained control that this system
       call provides, you probably want  to  use  the  GCC  built-in
       function __builtin___clear_cache(), which provides a portable
       interface across platforms supported by  GCC  and  compatible
       compilers:

//Maybe 'and compatible compilers' is redundant and I should remove it?

           void __builtin___clear_cache(void *begin, void *end);

       On  platforms  that  don't require instruction cache flushes,
       __builtin___clear_cache() has no effect.

       Note: On some GCC-compatible compilers, such  as  clang,  the
       prototype for this function uses char * instead of void *.


On 12/11/20 7:22 PM, Alejandro Colomar (man-pages) wrote:
> Hi all,
> 
> Please review this text:
> 
> [
> NOTES
>        Unless  you  need  the finer grained control that this system
>        call provides, you probably want  to  use  the  GCC  built-in
>        function  __builtin___clear_cache(),  which  provides  a more
>        portable interface:
> 
>            void __builtin___clear_cache(void *begin, void *end);
> 
>        On platforms that don't require  instruction  cache  flushes,
>        __builtin___clear_cache() has no effect.
> 
>        Note:  On  some  GCC-compatible compilers, such as clang, the
>        prototype for this function uses char * instead of void *.
> ]
> 
> Thanks,
> 
> Alex
> 
> On 12/11/20 7:02 PM, Alejandro Colomar (man-pages) wrote:
>> Hi Michael,
>>
>> On 12/11/20 9:15 AM, Michael Kerrisk (man-pages) wrote:
>>> i Alex,
>>>
>>> On 12/10/20 9:56 PM, Alejandro Colomar (man-pages) wrote:
>>>> Hi all,
>>>>
>>>> v2:
>>>>
>>>> [
>>>> NOTES
>>>>        Unless  you  need  the finer grained control that this system
>>>>        call provides, you probably want  to  use  the  GCC  built-in
>>>>        function  __builtin___clear_cache(),  which  provides  a more
>>>>        portable interface:
>>>>
>>>>            void __builtin___clear_cache(void *begin, void *end);
>>>> ]
>>>
>>> This seems a reasonable text to me, but I think it would be helpful
>>> to say a little more precisely what kind of portability we are
>>> talking about here.
>> Sure.
>>
>>>
>>> Greater ortability across Linux architectures? Greater portability
>>> across platforms supported by GCC (including non-Linux) platforms?
>>> Something else?
>>
>> '... which provides a portable interface across platforms supported by
>> GCC:' sounds good.
>>
>> Maybe GCC devs have something more to add.
> 
>>
>> Thanks,
>>
>> Alex
>>
>>>
>>> Thanks,
>>>
>>> Michael
>>>
>>>
>>
> 

-- 
Alejandro Colomar
Linux man-pages comaintainer; https://www.kernel.org/doc/man-pages/
http://www.alejandro-colomar.es