[LTP] [PATCH RFC] lib: add helper funcs to save and restore /proc|sys content

[Jan Stancek]

----- Original Message -----
> Hi!
> > To avoid adding specially crafted functions for every feature
> > where we need to save/restore some proc/sys config, this patch
> > introduces a struct (linked list) where user pushes files names
> > whose values should be saved. These can be later restored in
> > cleanup or during the test.
> 
> This is a great idea, but I guess that the user API could be even more
> simplified.
> 
> I would go for an NULL terminated array of strings that could be passed
> in the tst_test structure. Also that way the values would be restored in the
> test library even after the test has crashed.
> 
> Something as:
> 
> static const char *save_restore[] = {
> 	"/proc/sys/kernel/core_pattern",
> 	"/proc/sys/kernel/numa_balancing",
> 	NULL,
> };
> 
> 
> static struct tst_test test = {
> 	...
> 
> 	.save_restore = save_restore,
> };
> 
> What do you think?

Looks good to me - I agree this makes it easier for user.

I was already thinking about corner cases with function
approach, but that would be easy to add if we find need
for it later.

I'll post v2 that uses tst_test struct.

Regards,
Jan

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