Re: [dpdk-dev] [PATCH] eal: bus scan and probe never fail

[Thomas Monjalon <thomas@monjalon.net>]

09/10/2017 20:21, Don Provan:
> From: Shreyansh Jain [mailto:shreyansh.jain@nxp.com]
> >...
> > This is where I have disagreement/doubt.
> > Reporting error code from rte_bus_scan would do two things:
> > 
> > 1. rte_eal_init is not designed to ignore/log-only these errors - it
> > would quit initialization. (But, this can be changed)
> > 2. What should rte_eal_init do with this error? rte_bus_scan would have
> > already printed the problematic bus->scan() failure.
> 
> These practical problems confirm to me that the failure of a bus
> scan is more of a strategic issue: when asking "which devices can
> I use?", "none" is a perfectly valid answer that does not seem
> like an error to me even when a failed bus scan is the reason for
> that answer.
> 
> From the application's point of view, the potential error here
> is that the device it wants to use isn't available. I don't see that
> either the init function or the probe function will have enough
> information to understand that application-level problem, so
> they should leave it to the application to detect it.

Thank you Don. I think you convinced me.