Re: [Qemu-devel] [PATCH V7 00/14] add qmp/hmp interfaces for internal snapshot info

[Stefan Hajnoczi <stefanha@gmail.com>]

On Fri, Mar 01, 2013 at 09:47:29AM +0800, Wenchao Xia wrote:
> 于 2013-2-28 23:57, Stefan Hajnoczi 写道:
> >On Tue, Feb 26, 2013 at 06:40:14PM +0800, Wenchao Xia wrote:
> >>   This serial of patches does two things: merge some info code
> >>in qemu-img, and add following interfaces:
> >>1) qmp: query-images
> >>2) qmp: query-snapshots
> >>3) hmp: show internal snapshot info on a single block device
> >>   These patches follows the rule that use qmp to retieve information,
> >>hmp layer just do a translation from qmp object it got, so almost
> >>every hmp interface may have a correlated qmp interface.
> >>   To make code graceful, snapshot retrieving code in qemu and qemu-img
> >>are merged into block.c, and some function name was adjusted to make it
> >>tips better. Now it works as:
> >>
> >>    qemu          qemu-img
> >>
> >>dump_monitor    dump_stdout
> >>      |--------------|
> >>             |
> >>            qmp
> >>             |
> >>           block
> >
> >This summary does not explain how the new commands relate to query-block
> >or why they are necessary.
> >
> >It is also useful to include QMP examples or the QMP docs in the cover
> >letter so reviewers know what you are trying to achieve.
> >
>   OK, a better explaination would be added in the cover-letter.

Thanks.  When reviewers don't know your goal at the start of their
review, they may object to things that make sense at the end of the
series because they do not have enough context yet.  A series where the
goal is unclear also risks a higher number of review-fix cycles because
the reviewers haven't bought into the idea yet.

It is in everyone's interest to explain the goal in the cover letter.
Then the patches get reviewed more smoothly and merged faster.

This is a general thought I wanted to share and I struggle with it
myself sometimes when I submit patch series.

Stefan