Re: git: 7ae879b14a20 - main - kern_procctl(): convert the function to be table-driven

On Tue, Oct 19, 2021 at 02:04:15PM -0700, John Baldwin wrote:
> On 10/19/21 1:51 PM, Cy Schubert wrote:
> > In message <91ebf9d8-5547-8570-18cb-26a58baf89ba@FreeBSD.org>, John Baldwin
> > wri
> > tes:
> > > On 10/19/21 1:35 PM, Cy Schubert wrote:
> > > > In message <202110192004.19JK4jN3069844@gitrepo.freebsd.org>, Konstantin
> > > > Belous
> > > > ov writes:
> > > > > The branch main has been updated by kib:
> > > > > 
> > > > > URL: https://cgit.FreeBSD.org/src/commit/?id=7ae879b14a2086df521c59c4a379d
> > > 3a0
> > > > > 72e08bc6
> > > > > 
> > > > > commit 7ae879b14a2086df521c59c4a379d3a072e08bc6
> > > > > Author:     Konstantin Belousov <kib@FreeBSD.org>
> > > > > AuthorDate: 2021-10-15 18:57:17 +0000
> > > > > Commit:     Konstantin Belousov <kib@FreeBSD.org>
> > > > > CommitDate: 2021-10-19 20:04:34 +0000
> > > > > 
> > > > >       kern_procctl(): convert the function to be table-driven
> > > > >       Reviewed by:    emaste, markj
> > > > >       Sponsored by:   The FreeBSD Foundation
> > > > >       MFC after:      1 week
> > > > >       Differential revision:  https://reviews.freebsd.org/D32513
> > > > > ---
> > > > >    sys/kern/kern_procctl.c | 123 +++++++++++++++++++++++++++---------------
> > > ----
> > > > > --
> > > > >    1 file changed, 69 insertions(+), 54 deletions(-)
> > > > > 
> > > > > diff --git a/sys/kern/kern_procctl.c b/sys/kern/kern_procctl.c
> > > > > index eb36f0822938..90c5e63c7219 100644
> > > > > --- a/sys/kern/kern_procctl.c
> > > > > +++ b/sys/kern/kern_procctl.c
> > > > > @@ -949,7 +957,14 @@ kern_procctl(struct thread *td, idtype_t idtype, id_t
> > >   id
> > > > > , int com, void *data)
> > > > >    		error = EINVAL;
> > > > >    		break;
> > > > >    	}
> > > > > -	if (tree_locked)
> > > > > -		sx_unlock(&proctree_lock);
> > > > > +
> > > > > +	switch (cmd_info->lock_tree) {
> > > > > +	case SA_XLOCKED:
> > > > > +		sx_xunlock(&proctree_lock);
> > > > > +		break;
> > > > > +	case SA_SLOCKED:
> > > > > +		sx_sunlock(&proctree_lock);
> > > > > +		break;
> > > > > +	}
> > > > >    	return (error);
> > > > >    }
> > > > > 
> > > > 
> > > > Should SA_* in fact be LA_*? SA_* in sys/sx.h assumes INVARIANTS whereas
> > > > LA_* in sys/lock.h has no such requirement.
> > > 
> > > Both are for "assertions".  The LA_* constants aren't really public but are
> > > the values used for witness_assert() that various foo_assert() routines in
> > > locking APIs (mtx_assert/sx_assert, etc.) can use.  For locking APIs, the
> > > type-specific macros are the ones you use, e.g. SA_* with sx_assert().
> > > 
> > > Given that, SA_* is the closest match here.
> > 
> > We'll need some #ifdefs for non-INVARIANTS built kernels, as it stands
> > buildkernel is broken.
> 
> So it is helpeful if your e-mail starts with "the build is broken". :)
> 
> That said, I think the issue is that SA_* (and LA_*) have to date only been
> used for assertions and are thus only relevant when INVARIANTS is defined.
> It's probably simplest to just expose SA_* always if that is what is
> needed.

Should be fixed by c7f38a2df1f0.