Re: netbsd32 emulation in driver open() or read()

On 30 August 2011 16:05, Manuel Bouyer <bouyer%antioche.eu.org@localhost> wrote:

On Tue, Aug 30, 2011 at 10:19:20AM -0400, Christos Zoulas wrote:
> On Aug 30, 3:18pm, bouyer%antioche.eu.org@localhost (Manuel Bouyer) wrote:
> -- Subject: Re: netbsd32 emulation in driver open() or read()
>
> | > Yes, look at PK_32 in the process flags. If you are going to do this, please
> | > look at what FreeBSD did with bpf_ts/bpf_xhdr and the time format changes
> | > and do the same (provide timespec/bintime etc). This is how they handle
> | > compatibility mode too.
> |
> | This is related to the BIOCSTSTAMP ioctl isn't it ? I can see how it's used
> | in kernel but I couldn't find it in userland. So, to me it looks like
> | the old bpf_hdr is used most of the time ...
> | I'm not sure if it's worth implementing BIOCSTSTAMP (and we have to assure
> | compat for bpf_hdr anyway)
>
> Might as well bite the bullet and do the whole thing because with 10Gb+
> ethernet what we have now just does not cut it.

This is not only the BIOCSTSTAMP that we need then, but also the zero-copy
stuff, and probably more. And userland tools to use it (because AFAIK
freebsd's tcpdump still uses the old bpf_hdr ...)

That may be nice to have, but won't help with my problem which is
getting a N32 mips binary to talk to a N64 kernel.

If the structure was versioned to have 64 bit fixed sized timestamps, then the problem goes away for new code, though it does leave a COMPAT50 issue for older code...