Re: 9pfs developers docs

[Greg Kurz]

On Mon, 01 Feb 2021 12:30:52 +0100
Christian Schoenebeck <qemu_oss@crudebyte.com> wrote:

> On Montag, 1. Februar 2021 10:24:26 CET Greg Kurz wrote:
> > On Sun, 31 Jan 2021 19:23:52 +0100
> > 
> > Christian Schoenebeck <qemu_oss@crudebyte.com> wrote:
> > > Hi,
> > 
> > Hi Christian,
> > 
> > > I started setting up some developer documentation for 9pfs:
> > >   https://wiki.qemu.org/Documentation/9p
> > > 
> > > Still quite a bunch that should be added (e.g. there should be a section
> > > about threads and coroutines), but at least it's a start ...
> > 
> > I agree that a bunch of other things should be documented, but that's
> > definitely a great start. Thanks for doing this !
> > 
> > Just one remark on the topology diagram:
> > 
> > https://wiki.qemu.org/File:9pfs_topology.png
> > 
> > It gives the impression that the 9p transport and server can
> > handle multiple guests, which they certainly don't : each
> > 9p server lives in exactly one device which is exposed to
> > exactly one guest.
> 
> Right, I haven't considered that the diagram might be interpreted that way. 
> My 
> primary intention was to show the 3 main components of 9pfs from design 
> perspective and secondary showing that multiple guests can share storage.
> 
> So what would be better: a) duplicating the server side in the diagram (then 
> the image might become a bit large in height), b) dropping the multiple 
> guests, c) making the issue with server instances clear in the text?

I'd rather go for b)

> 
> If there are other things that you might think should be outlined by 
> additional diagram(s) let me know, then I can add that in one rush.
> 
> --
> 
> BTW I'm no longer able to run the 'local' 9p tests, --slow doesn't work for 
> me. If you don't have an idea what I might be missing, then I have to look 
> why 
> the CLI parameter is not interpreted.
> 

Is it that '-m slow' doesn't work when running 'qos-test' or
that 'make check-qtest SPEEP=slow' doesn't run the slow tests ?

The latter was discussed on IRC last year but I don't know if
anyone has tried to investigate this yet.

Nov 24 11:36:53 <groug> th_huth, Hi. FYI it seems that the meson conversion 
kinda broke 'make check SPEED=slow'. Test programs aren't passed '-m slow'
Nov 24 11:51:42 <f4bug> th_huth: do you know who uses/tests SPEED=slow?
Nov 24 11:52:03 <f4bug> th_huth: I thought this was a block-related feature
Nov 24 11:52:44 <groug> f4bug, it is supposedly used by gitlab CI
Nov 24 11:52:59 <groug> .gitlab-ci.yml:    MAKE_CHECK_ARGS: check-qtest 
SPEED=slow
Nov 24 12:50:53 <th_huth>       groug, I'm also running make check SPEED=slow 
manually sometimes ... I guess that got lost in the conversion to ninja ... 
bonzini, did you ever try?
Nov 24 12:51:03 <bonzini>       no it shouldn't
Nov 24 12:51:21 <th_huth>       let me check...
Nov 24 12:51:40 <bonzini>       ah, the tests are chosen correctly but -m slow 
is lost
Nov 24 12:52:02 <groug> yes that's what I see
Nov 24 12:54:04 <groug> bonzini, missing bits in scripts/mtest2make.py ?
Nov 24 12:54:28 <bonzini>       groug: sort of, but assuming that all 
executables support -m slow wouldn't work

Cc'ing Thomas and Paolo for additional details.

> Best regards,
> Christian Schoenebeck
> 
>