Re: [Qemu-devel] [PATCH] hmp: Improve 'info mtree' with optional parm for mapinfo

[Paolo Bonzini <pbonzini@redhat.com>]

On 07/09/2016 02:48, Thorsten Kohfeldt wrote:
> From: Thorsten Kohfeldt <mailto__qemu-devel@nongnu.org>
> Date: Wed, 31 Aug 2016 22:43:14 +0200
> Subject: [PATCH] hmp: Improve 'info mtree' with optional parm for mapinfo
> 
> Motivation
> When 'tuning' 'quirks' for VFIO imported devices, it is not easy to
> directly grasp the implications of the priorisation algorithms in place
> for the 'layered mapping' of memory regions.
> Even though there are rules (documented in docs/memory.txt), once in a
> while one might question the correctness of the actual implementation of
> the rules.
> Particularly, I believe I have uncovered a divergence of (sub-)region
> priorisation/order/visibility in a corner case of importing a device
> (which requires a 'quirk') with mmap enabled vs. mmap disabled.
> This modification provides a means of visualising the ACTUAL
> mapping/visibility/occlusion of subregions within regions, whereas the
> current info mtree command only lists the tree of regions (all, visible
> and invisible ones).
> It is primarily intended to provide support for easy presentation of my
> cause, but I strongly believe this modification also has general purpose
> advantages.

It is a useful addition, but I think a simpler presentation is also
fine.  What about "info mtree -f" which would visit the FlatView instead
of the tree?  The patch would probably be much shorter.

Thanks,

Paolo