On Mon, 11 Jul 2022 23:15:26 +0200
Thomas Monjalon <tho...@monjalon.net> wrote:
> 05/07/2022 22:44, Stephen Hemminger:
> > The DPDK is not designed to be used from a signal handler.
> > Add a notice in the documentation describing this limitation,
> > similar to Linux signal-safety manual page.
> >
> > Bugzilla ID: 1030
> > Signed-off-by: Stephen Hemminger <step...@networkplumber.org>
> > Acked-by: Tyler Retzlaff <roret...@linux.microsoft.com>
> > Acked-by: Chengwen Feng <fengcheng...@huawei.com>
> > ---
> > doc/guides/prog_guide/env_abstraction_layer.rst | 15 +++++++++++++++
> > 1 file changed, 15 insertions(+)
> >
> > diff --git a/doc/guides/prog_guide/env_abstraction_layer.rst
> > b/doc/guides/prog_guide/env_abstraction_layer.rst
> > index 67842ae27207..de7ee92bba39 100644
> > --- a/doc/guides/prog_guide/env_abstraction_layer.rst
> > +++ b/doc/guides/prog_guide/env_abstraction_layer.rst
> > @@ -818,6 +818,21 @@ Known Issues
> >
> > The debug statistics of rte_ring, rte_mempool and rte_timer are not
> > supported in an unregistered non-EAL pthread.
> >
> > ++ signal safety
> > +
> > + The DPDK library is not designed to be async-signal-safe.
> > + Except where explicitly stated otherwise [#]_, the DPDK functions are
> > nonreentrant and are unsafe to call from a signal handler.
> > +
> > +.. [#] Only the function ``rte_dump_stack()`` can safely be called from
> > signal handler in this version of DPDK.
>
> Really? Are you sure?
>
> Note: the use of [#] is probably limited to a single usage in the page?
Yes. this is true, please apply this patch.
It is not safe to call functions that do any of the following:
printf
malloc
according to Linux async-signal-safe documentation
And because these all have locking or equivalent atomic the following
in DPDK are unsafe.
rte_ring
rte_timer
rte_spinlock, rte_rwlock, ...
any PMD operations
