[LTP] Test library API changes

[Jan Stancek]

----- Original Message -----
> From: "Cyril Hrubis" <chrubis@suse.cz>
> To: "Jan Stancek" <jstancek@redhat.com>
> Cc: ltp@lists.linux.it
> Sent: Thursday, 10 March, 2016 5:57:21 PM
> Subject: Re: [LTP] Test library API changes
> 
> Hi!
> Up to date version is at usuall place:
> 
> https://github.com/metan-ucw/ltp
> 
> 
> Changes are:
> 
> * Now we use env variable for SHM path
> 
>   - I was thinking about setting it to the /proc path if proc is mounted
>     but that way we would have to keep the fd open (and it would occupy
>     fd=3) and I think that the less resources the library occupy the
>     better
> 
> * The rest of the default test options -I and -C are now working
> 
> * I've given up on SAFE_MACROS in cleaup for now
> 
>   - We may add them later, but I would like to get this merged ideally
>     before we do another release and doing this would take some time

I think we have this problem already. tst_brk() will call tst_vbrk_(),
which calls cleanup_ipc(), which is using SAFE_* macros. It looks like
we'll get infinite loop if any of those fail.

> 
> * All relevant parts of test-writing-guidelines should be now rewritten
> 
>   - There are couple of functions that still take cleanup as fist
>     parameter and that are not exported to the new library but that
>     should be all that is missing

"Child processes started via exec*, or any other processes must initialize the
checkpoint by calling 'TST_CHECKPOINT_INIT()' before usage."
This doesn't sound correct for newlib. We now have "tst_checkpoint_open()".

---

'To make sure cleanup() was called only once LTP has a helper
"TST_DECLARE_ONCE_FN"'
TST_DECLARE_ONCE_FN is declared in test.h, it doesn't look like newlib
can use it at the moment.

---

I'm not sure it is enough to make cleanup() call only once. It looks like
we still can get into situation where we call "do_cleanup();cleanup_ipc();"
more than once (if we hit tst_brk in multiple threads with newlib)

---

Can we remove "SAFE_CLOSE(ipc_fd);" from cleanup_ipc()? This fd
is already closed in setup_ipc().

---

Should "struct tst_test *tst_test" be initialized to NULL?
Some tst_res.c oldlib functions are using it, but it is initialized only
if you use newlib, at tst_run_tcases().

> 
> 
> Anything else that should be done before we can merge it?

I only made a compile test on some old/recent RHEL distros
and ran some newlib testcases by hand. This worked OK.

Have you tried running all of the (oldlib) tests on
various arches/releases to see if we haven't regressed?

I could run it against various RHEL majors, it
would take couple days.

Regards,
Jan

> 
> --
> Cyril Hrubis
> chrubis@suse.cz
>