Re: Fw: framebuffer blitting performance loss 2.6.12 -> 2.6.13-rc3

[Knut Petersen <Knut_Petersen@t-online.de>]

Hi Tony,

>
> Thank you for your persistence.  I think I know the culprit.  Someone
> insisted on using memcpy in fb_pad_aligned_buffer().  I have already
> fixed this before, but apparently, the memcpy was brought back.  Try
> the attached patch and let me know.
>
> Tony

Replacing memcpy() with this inline code helps. Performance is slightly 
slower than
it was in 2.6.12,  but this is hardly measurable and could be caused by 
other changes
in the kernel.

The most affected test, (test 3, cyblafb, ypan) now is about 7ms slower 
than it was
in 2.6.12. Without your patch the performance penalty was 202ms!

Yes, please send the patch to Linus asap, it´s a must for 2.6.13.

Someone should look at memcpy ;-)

cu,
 Knut


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