Re: [dpdk-dev] [PATCH] app/testpmd: fix testpmd exit using ctrl+d

["Singh, Jasvinder" <jasvinder.singh@intel.com>]

> -----Original Message-----
> From: Thomas Monjalon [mailto:thomas@monjalon.net]
> Sent: Wednesday, July 25, 2018 9:19 AM
> To: Dumitrescu, Cristian <cristian.dumitrescu@intel.com>
> Cc: dev@dpdk.org; Mordechay Haimovsky <motih@mellanox.com>; Singh,
> Jasvinder <jasvinder.singh@intel.com>; Iremonger, Bernard
> <bernard.iremonger@intel.com>; Pattan, Reshma
> <reshma.pattan@intel.com>; olivier.matz@6wind.com
> Subject: Re: [dpdk-dev] [PATCH] app/testpmd: fix testpmd exit using ctrl+d
> 
> 24/07/2018 18:59, Dumitrescu, Cristian:
> > From: Mordechay Haimovsky [mailto:motih@mellanox.com]
> > >
> > > Even after this fix we still have setups that use netvsc  for
> > > example,  on which testpmd exits with rte_panic right after loading
> > > it even without touching the KBD.
> > >
> > > I recommend returning the previous prompt routine in
> > > test-pmd/cmdline.c and rework the SOFTNIC section there, preferably
> > > moving its poll section to use rte_service in a separate file
> > > cleaning the CLI files from PMD-specific implementation.
> > >
> > > From: Thomas Monjalon [mailto:thomas@monjalon.net]
> > > >
> > > > Important note:
> > > > 	testpmd is currently really broken.
> > > > 	We cannot have a RC2 until it is fixed.
> > > >
> >
> > First, testpmd is not really broken, as only thing that changed is the Ctrl + D
> behavior. I agree this is an issue that we need to fix, as it looks that it is
> breaking some automation scripts for some people.
> >
> > The change in behavior for Ctrl + D exit is caused by replacing the call to
> cmdline_interact() with calling cmdline_poll() in a loop. These two approaches
> should be identical in behavior, but it looks like they are not due to some issue
> in the cmdline library. Jasvinder proposed a quick patch, but it looks like
> something else needs to be fixed in cmdline library in order to bring
> cmdline_poll() on parity with cmdline_interact(). Any advice from Olivier would
> be very much appreciated!
> >
> > It is really a bad practice to use cmdline_interact() in testpmd, as it is a
> blocking call that prohibits doing other things on the same thread that runs the
> CLI. Sometimes we need to run other things on the same core, e.g. the slow
> softnic_manage() function.
> >
> > Worst case scenario: We can revert the cmdline_poll() back to
> cmdline_interact(), this is a small change, but not the proper way of doing
> things, as this is simply hiding the issue in cmdline library. It would also prevent
> us from testing some Soft NIC functionality.
> 
> There are some crashes, even without touching the keyboard.

Thomas, could you be specific here so that we can reproduce the issues you are mentioning? Thanks.

> So yes, we should revert.
>