On Mon, Oct 27, 2014 at 06:43:27PM -0400, David Miller wrote: > From: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > Date: Mon, 27 Oct 2014 14:09:38 -0700 > > > Perhaps sparc should be defining CONFIG_HAVE_GENERIC_RCU_GUP. > > > > We really should switch x86 to the generic version - from a quick read > > it looks like it will work without needing any changes. > > > > Steve, thoughts? > > We need to add the necessary hooks to the generic code so that x86 > doesn't so specualtive gets and instead do direct increments, > otherwise it's a performance regression, and then sparc can make use > of that as well. Agreed, I think x86 may require a helper to read 64-bit ptes (as it can't do that atomically). Also I think there's some subtlety in the way access_ok works that should be checked. The overall structure of the code looks the same to me, and I think it would be beneficial to extend then use the generic version for x86. Cheers, -- Steve -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html