> > Don't introduce a config option. If you do this by ifdef, use ifdef on
> > the arches that you used as default. On those arches the memmove is
> > definitely a win.
> > You could even test it unconditionally on i386 or x86_64. A copy may be
> > faster than keeping it in place, as you touch the data many times, but
> > copy it only once.
>
> Do you thing that copy of whole frames (up to 1.5 kilobytes!) is faster
> than unaligned accesses to header on x86/x86_64 (which is definitly used
> by vast majority of this driver users)?
You will in most cases touch more than just the header processing
that frame. Eventually you will copy the frame anyway. It needs to
be tested. The bottleneck is probably reading the buffer from a cold
cache. The assumption cannot be made without testing, but is worth
testing.
Regards
Oliver
-------------------------------------------------------------------------
Take Surveys. Earn Cash. Influence the Future of IT
Join SourceForge.net's Techsay panel and you'll get the chance to share your
opinions on IT & business topics through brief surveys - and earn cash
http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV
_______________________________________________
linux-usb-devel@lists.sourceforge.net
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
