confused by osmo-bts rsl.c:bts_supports_cm()

This is merely a historical archive of years 2008-2021, before the migration to mailman3.

A maintained and still updated list archive can be found at https://lists.osmocom.org/hyperkitty/list/OpenBSC@lists.osmocom.org/.

Keith keith at rhizomatica.org
Mon Sep 10 13:36:43 UTC 2018



On 10/09/18 02:50, Neels Hofmeyr wrote:
>
> b) the code path that would trigger the mode modif currently doesn't, and
> instead we assign a new lchan (
> http://git.osmocom.org/osmo-bsc/tree/src/osmo-bsc/assignment_fsm.c?id=981f8b934771460354163dd148a5ecab46dd4476#n347
> ).
Thanks for explaining that!

> c) Even though current osmo-bsc never invokes Chan Mode Modif, I kind of
> expected osmo-bts code to also invoke the same function somewhere for the chan
> act case. But it doesn't :P
>
>
> osmo-nitb, however, doesn't do late assignment, so commonly reaches the Chan
> Mode Modif code path.
>
> Either way, even though osmo-bsc doesn't currently use this code path, we still
> want it fixed for the future, not only for osmo-nitb.
>
>
> Solution: bts_supports_cm() should never be fed with dynamic pchan kinds.  To
> test my patch, I'd need to setup an osmo-nitb ... Keith, can you take over the
> test whether this fixes the problem instead?
>
OK tested, works fine, I have pushed gerrit #10864

> Placed it on branch neels/dyn_modif in osmo-bts; it's just:
>
> -       if (bts_supports_cm(lchan->ts->trx->bts, lchan->ts->pchan, lchan->tch_mode) != 1) {
> +       if (bts_supports_cm(lchan->ts->trx->bts, ts_pchan(lchan->ts), lchan->tch_mode) != 1) {
I pushed before actually looking at your branch, you'ld probably prefer
a different commit message.
and maybe not include the logging changes.. anyway, please comment on
gerrit.
>
> If it's any difficulty to build osmo-bts, I do have a compile for sysmoBTS
> ready to fire up and could also test myself if you ask me back.




No problems, I also have a build machine for sysmoBTS ready, but I am
getting great
value at the moment from the LimeSDR-mini and osmo-trx-lms running on x86!!
>
> So a code refactoring would be good to make it easier to add new code around
> checking pchan types -- https://osmocom.org/issues/1902. Such a refactoring has
> already happened in osmo-bsc, but that's unrelated to this issue.)
Good to know, it might help me to spot these things in the future.
>
> ~N

k/


-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 801 bytes
Desc: OpenPGP digital signature
URL: <http://lists.osmocom.org/pipermail/openbsc/attachments/20180910/c887e4bd/attachment.bin>


More information about the OpenBSC mailing list