Re: [dpdk-dev] [PATCH v9 6/9] eal: auto detect iova mode

[Thomas Monjalon <thomas@monjalon.net>]

06/10/2017 05:25, santosh:
> 
> On Friday 06 October 2017 05:49 AM, Thomas Monjalon wrote:
> > 20/09/2017 13:23, Santosh Shukla:
> >> For auto detection purpose:
> >> * Below calls moved up in the eal initialization order:
> >> 	- eal_option_device_parse
> >> 	- rte_bus_scan
> >>
> >> Based on the result of rte_bus_scan_iommu_class - select iova
> >> mapping mode.
> > It does not explain why you need to move things up.
> 
> For that one should understand eal_init sequence first.
> Should know about _option_device_parse and rte_bus_scan() dependency.
> 
> After that bus_scan is a need for _get_iommu_class() of api to know that
> - kdrv is igb/uio/vfio etc.. That's why. Refer work history.
> Again V9 series happened not for fun. I diagress on your comment.

This is the basics of writing a commit log.
You have to explain why things are done.
You move things because of dependencies without explaining them.

And I'm pretty sure this move will cause big troubles.
For instance, have you tried shared library mode?

One more comment, you are considering only devices scanned at initialization.
What happens when a new device is plugged in?

I can push it as is, given there are some Reviewed-by and Tested-by.
I am trying to avoid you a revert of this patch when one will discover
some major bugs.
But I wonder whether it's worth given how you welcome it.