On Tue, Jun 10, 2014 at 04:13:04PM -0700, H. Peter Anvin wrote: > After a recent problem in the x86 tree, which seems to be the heaviest > but not the only user of these functions, I went through and did a > patchset to revamp the *user space* unaligned/endian accessor > functions. As much as I think it is downright pathetic that this > functionality still isn't part of the C standard, that is life and we > have to deal with it. Furthermore, although glibc has a pretty nice > set of functions for byte swapping in <endian.h>, taken from FreeBSD I > believe, some older systems don't support them. > > This variant tries to fill in all the holes. It assumes that > <endian.h> define the functions as macros if they exist, as I don't > know any other way of probing for them without reaching for autoconf, > but that should be valid enough of an assumption in this case. > > The hope is that this should give reasonable, if not optimal, code > generation on most processors, and give a hook where arch maintainers > can add their own changes if needed. This looks like a very complex solution to a simple problem. We want a shared implementation of the *user space* unaligned/endian accessor functions. But do we really want *fast* versions for our use? This is not a new libc that should generate optimal code, but only something were we want to provide e working implmentation for use in our user-space tools. A much simpler approach without any fallback to arch specific version etc. is everything we need. Sam -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
