struct ifnet locking [was Re: IFEF_MPSAFE]

[Nick Hudson <skrll%netbsd.org@localhost>]

On 11/17/17 07:44, Ryota Ozaki wrote:
> On Wed, Nov 15, 2017 at 1:53 PM, Ryota Ozaki <ozaki.ryota%gmail.com@localhost> wrote:
> > On Fri, Nov 10, 2017 at 6:35 PM, Ryota Ozaki <ozaki.ryota%gmail.com@localhost> wrote:
> > > Hi,
> > >
> > > http://www.netbsd.org/~ozaki-r/IFEF_MPSAFE.diff
> > >
> > > I'm going to commit the above change that integrates
> > > IFEF_OUTPUT_MPSAFE and IFEF_START_MPSAFE flags into
> > > IFEF_MPSAFE.
> > >
> > > The motivation is to not waste if_extflags bits. I'm now
> > > trying to make if_ioctl() hold KERNEL_LOCK selectively
> > > for some reasons as well as if_start() and if_output().
> > BTW this is a patch for this plan:
> >    http://www.netbsd.org/~ozaki-r/if_ioctl-no-KERNEL_LOCK.diff
> >
> > It removes KERNEL_LOCK for if_ioctl from soo_ioctl and
> > selectively takes it in doifioctl. To this end, some fine-grain
> > KERNEL_LOCKs have to be added where calling components/functions
> > that aren't MP-safe.
> Revised rebased on latest NET_MPSAFE macros. The new patch also provides
> similar macros:
>    http://www.netbsd.org/~ozaki-r/if_ioctl-no-KERNEL_LOCK.revised.diff
>
>    ozaki-r
Hi,

Can you document the protection requirements of the struct ifnet 
members, e.g. if_flags.

Ideally by annotating it like struct proc

http://src.illumos.org/source/xref/netbsd-src/sys/sys/proc.h#230

Thanks,

Nick