Gilles Chanteperdrix wrote:
Jan Kiszka wrote: > Gilles Chanteperdrix wrote: > > Would not it be simpler to put a pointer to the task_struct ? After all, > > it already has a pid, comm and mm, and a file descriptor will not > > survive a task_struct thanks to automatic closing of file descriptors.> > Hmm, hmm, hmmmm... Sounds reasonable, should be safe.Actually no, we can not do that because a task_struct may well disappear and the rtdm_process continue to exist as long as another thread uses the same mm.
Because we cleanup on mm exit, not task exit, right? OK, looks like I originally spent a few more thoughts than this time :-/.
> > > > > Could you> > > live without the check until we have per-process fd tabled, or was it > > > essential for the select thing?> > > > An application which I ported to Xenomai (and which uses the select> > call) closes all file descriptors in a for loop. The purpose of this > > loop is, I guess, to avoid leaving a file descriptor opened that was > > passed through exec.> > OK. > > So, will you change rtdm_process too? Thanks.I commited the select support, without any change to rtdm_context_get or rtdm_process. So, now, how do you prefer this to be fixed, by adding an mm struct to the rtdm_process struct ? By the way, after thinking about it I can live without this fix: I just have to stop the loop closing file descriptors at 768, so that it will not try to close RTDM file descriptors.
If you can live with it, I would vote for fixing it by the intended redesign via per-process fds.
While commiting the support for select, I also had a dependency problem in Kconfig: when support for posix select is enabled the posix module uses a function defined in the RTDM module. So, there is one invalid configuration: posix built-in with support for select and rtdm built as a module. I could not find a way to express this condition in the Kconfig language, so I just made a comment depend on this condition, but would be happy if anyone found a better solution.
I would say:
config POSIX
select RTDM if OPT_SELECT
Jan
signature.asc
Description: OpenPGP digital signature
_______________________________________________ Xenomai-core mailing list Xenomai-core@gna.org https://mail.gna.org/listinfo/xenomai-core
