pmap_copy for ARMv6/v7

[Zbyszek Bodek]

On 30.05.2013 19:27, Alan Cox wrote:
> On 05/28/2013 17:17, Zbigniew Bodek wrote:
>> Hello Everyone,
>>
>> I would like to share with you the patch adding pmap_copy()
>> functionality to pmap-v6.c. This is the last but not least of
>> the pmap improvements done as a part of Semihalf work on
>> Superpages support.
>>
>> We tried various technics to test the patch on our target.
>> Apart from obvious long term stability tests and others,
>> we used a simple benchmark to measure fork system call time and overhead.
>>
>> The program can be downloaded from here:
>> http://berlin.ccc.de/~packet/fork_test.c
>>
>> A single fork time has increased as suspected (the program is not measuring
>> a real-life fork situation where child process is actually doing something)
>> but the average system overhead has decreased.
>> For 10000 fork(), 10000 vfork() and 10000 pthread_create() calls we observe
>> 100000 less vm_faults and shorter overall test time.
>>
>> If you have any suggestions or have an idea for benchmarking this
>> feature please share.
> 
> 
> From what you describe above, I think that you've done a reasonable job
> of testing.  The performance results are in line with what I would
> expect.  I wouldn't worry too much about obtaining further test results.
> 
> 
>> We will appreciate if you could test this patch on your ARM platforms and
>> send
>> us your review/feedback.
>>
> 
> 
> The patch looks fine.
> 
> Alan

Hello Alan,

Thank you very much for your review.

Patch has just been committed to FreeBSD HEAD:
http://svnweb.freebsd.org/base?view=revision&revision=251370

Best regards
Zbyszek Bodek