Re: [PATCH bpf-next v4 1/8] btf: Add a new kfunc set which allows to mark a function to be sleepable

From: Yosry Ahmed
Date: Fri Jul 22 2022 - 13:51:57 EST


On Fri, Jul 22, 2022 at 9:20 AM Alexei Starovoitov
<alexei.starovoitov@xxxxxxxxx> wrote:
>
> On Thu, Jul 21, 2022 at 7:13 PM Yosry Ahmed <yosryahmed@xxxxxxxxxx> wrote:
> >
> > From: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>
> >
> > This allows to declare a kfunc as sleepable and prevents its use in
> > a non sleepable program.
> >
> > Signed-off-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>
> > Signed-off-by: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
> > ---
> > include/linux/btf.h | 2 ++
> > kernel/bpf/btf.c | 13 +++++++++++--
> > 2 files changed, 13 insertions(+), 2 deletions(-)
> >
> > diff --git a/include/linux/btf.h b/include/linux/btf.h
> > index 1bfed7fa0428..6e7517573d9e 100644
> > --- a/include/linux/btf.h
> > +++ b/include/linux/btf.h
> > @@ -18,6 +18,7 @@ enum btf_kfunc_type {
> > BTF_KFUNC_TYPE_RELEASE,
> > BTF_KFUNC_TYPE_RET_NULL,
> > BTF_KFUNC_TYPE_KPTR_ACQUIRE,
> > + BTF_KFUNC_TYPE_SLEEPABLE,
> > BTF_KFUNC_TYPE_MAX,
> > };
>
> This patch needs refactoring using the new BTF_ID_FLAGS scheme.
> When you do that please update the Documentation/bpf/kfuncs.rst as well.
>
> Thanks!

Sent v5 rebased on top of the new kfunc flags infrastructure, and
added documentation for sleepable kfuncs.