RE: [PATCH] Coccinelle report script for refcounters
From: Julia Lawall
Date: Tue Jul 18 2017 - 07:53:19 EST
On Tue, 18 Jul 2017, Reshetova, Elena wrote:
> > On Tue, 18 Jul 2017, Elena Reshetova wrote:
> >
> > > The below script can be used to detect potential misusage
> > > of atomic_t type and API for reference counting purposes.
> > > Now when we have a dedicated refcount_t type and API with
> > > security protection implemented, people should be using it
> > > instead.
> > >
> > > Currently it still reports many occurences since we are
> > > nowhere near the end of our kernel-wide conversion execrise,
> > > but hopefully after couple of cycles more, the amount of
> > > output would be much more limited.
> > >
> > > Each script result must be analysed manually before any
> > > conversion, since refcount_t might not suit for certain
> > > purposes (for example if an object is not always destroyed
> > > upon refcounter reaching zero, if increments from zero are
> > > allowed in the code etc.)
> > >
> > > As we go further and get less results in output, we will
> > > improve the pattern to detect conversion cases more precisely.
> >
> > The regexps are the best you can do?
>
> They are simple and so far they were sufficient for the purpose since
> they found pretty much all the cases we are aware about. I was thinking
> on working to improve the pattern later on after we merge the bulk of
> conversions and I have some cycles free on that front.
>
> What would you suggest to do instead of regexps?
Is there anything about the definitions of these functions that indicates
why they are important?
julia
>
> Best Regards,
> Elena.
>
> >
> > julia
> >
> > >
> > > Elena Reshetova (1):
> > > Coccinelle: add atomic_as_refcounter script
> > >
> > > scripts/coccinelle/api/atomic_as_refcounter.cocci | 102
> > ++++++++++++++++++++++
> > > 1 file changed, 102 insertions(+)
> > > create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci
> > >
> > > --
> > > 2.7.4
> > >
> > >
>