On Thursday 15 November 2012, Rob Clark wrote: > On Thu, Nov 15, 2012 at 3:19 AM, Arnd Bergmann <arnd@xxxxxxxx> wrote: > > On Tuesday 13 November 2012, Russell King - ARM Linux wrote: > >> You're missing something; that is one of the greatest powers of open > >> source. The many eyes (and minds) effect. Someone out there probably > >> has a solution to whatever problem, the trick is to find that person. :) > >> > >> I think we have a working solution for this for ARM. It won't be suitable > >> for every arch, where they have 8-bit and 16-bit registers able to be > >> allocated by the compiler, but for architectures where the minimum register > >> size is 32-bit, what we have below should work. > > > > I don't mind at all adding the extension to ARM, and I think it's pretty > > cool that you guys actually found a working solution. > > > > The part that worries me is that we are making architecture independent > > code depend on a clever hack that may or may not be possible to implement > > on a given architecture, and that most architecture maintainers wouldn't > > know how to implement correctly even if it's possible. > > I could always send a 3rd version with a comment smashed on about why > that works if you think this is a problem.. Comments are always good, so I'd surely like to see those get added. As I said, I don't have any objections to the addition of your patch to the ARM code, which sounds useful to have. I still haven't heard a conclusive argument why we need to use get_user() rather than copy_from_user() in the DRM code. Is this about a fast path where you want to shave off a few cycles for each call, or does this simplify the code structure, or something else? Arnd _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
