Re: [PATCH v3 6/6] net/failsafe: fix removed device handling

["Gaëtan Rivet" <gaetan.rivet@6wind.com>]

On Mon, Jan 08, 2018 at 02:00:54PM +0000, Matan Azrad wrote:
> Hi Gaetan
> 

<snip>

> > > > Your environment does not include the function, but this is within
> > > > fs_flow_destroy (please update to include the context by the way it
> > > > helps a lot the review :). Afterward, line 162 ret is directly used as return
> > value.
> > > >
> > > I don't understand what do you mean.
> > >
> > > > Also, fs_err() would need to transform rte_errno when relevant
> > > > (mostly in failsafe_flow.c I think).
> > > >
> > > Your suggestion is always to update rte_errno to 0 in case the error is
> > because of removal?
> > >
> > 
> > If the error is indeed due to the device being absent, then rte_errno should
> > be set back to its previous value I think.
> So, I think it will require old rte_errno save before each device command...
> Why not to set it to 0 in the special case(removal) by the new internal API?
> 

Resetting it to 0 might be sufficient, yes.

There might be some old-school devs out-there that would such things as:

    do_thing_x();
    do_thing_y();
    do_thing_z();
    if (check_for_any_error(errno)) {
        abort();
    }

But I'm not too fond of this kind of pattern, so I'm not specifically
opposed to code that does not go with this flow.

-- 
Gaëtan Rivet
6WIND