[PATCH] Rename the glibc.tune namespace to glibc.cpu

[Tulio Magno Quites Machado Filho]

Siddhesh Poyarekar <siddhesh@sourceware.org> writes:

> On 07/16/2018 08:47 PM, Carlos O'Donell wrote:
>> This looks good to me. I'd like this to wait until 2.29 opens. I want to
>
> OK, I'll queue it up for 2.29.
>
>> minimize spurious changes. It would also be nice in 2.29 to rename the
>> options to arch_* prefixed options for those that are arch-specific.
>
> There's only the powerpc one that's named in a generic manner but is 
> architecture specific.

I'm not following your line of thought here:

 - glibc.cpu.hwcaps is specific to i386 and x86-64
 - glibc.cpu is specific to aarch64
 - glibc.cpu.cached_memopt is specific to powerpc, powerpc64 and powerpc64le

What am I missing?

> I'd actually like to discuss dropping the 
> tunable (and use hwcap_mask instead) but we can have that discussion for 
> 2.29.

Notice the optimization is not specific to a CPU, but specific to an user
scenario (cacheable memory).  In other words, the optimization can't be used
whenever PPC_FEATURE2_ARCH_2_07 because it could downgrade the performance when
cache-inhibited memory is being used.

-- 
Tulio Magno