Re: [PATCHv7 18/33] lib/vdso: Add unlikely() hint into vdso_read_begin()

[Vincenzo Frascino]

Hi Andrei,

On 10/24/19 10:30 AM, Vincenzo Frascino wrote:
[...]
>> Here is my test:
>> https://github.com/avagin/vdso-perf
>>
>> It is calling clock_gettime() in a loop for three seconds and then
>> reports a number of iterations.
>>
> 
> I am happy to run the test on arm64 and provide some results.
>

Please find below the results:

clock            | before     | after      | diff
==================================================
monotonic          17326692     17951770     3.6%
monotonic-coarse   43624027     44215292     1.3%
monotonic-raw      17541809     17554932     0.1%
boottime           17334982     17954361     3.5%

The improvement for arm64 for monotonic and boottime is around 3.5%.

I created a pull request on github to send to you back the changes I had
to do to vdso-perf to cross-compile it on arm64 [1].

[1] https://github.com/avagin/vdso-perf/pull/1


>> Thanks,
>> Andrei
>>
> 

-- 
Regards,
Vincenzo