Re: [fanotify] 7cea2a3c50: stress-ng.fanotify.ops_per_sec -23.4% regression

[Jan Kara]

On Tue 11-05-21 14:13:38, Amir Goldstein wrote:
> On Tue, May 11, 2021 at 9:51 AM kernel test robot <oliver.sang@xxxxxxxxx> wrote:
> >
> >
> >
> > Greeting,
> >
> > FYI, we noticed a -23.4% regression of stress-ng.fanotify.ops_per_sec due to commit:
> >
> >
> > commit: 7cea2a3c505e87a9d6afc78be4a7f7be636a73a7 ("fanotify: support limited functionality for unprivileged users")
> > https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master
> >
> 
> I am not sure how this is possible.
> This commit only changes permissions to perform the operation.
> Is the test not being run as root?

Yeah, I've stared at it for some time and didn't come up with a sensible
explanation either. I guess we need to try to reproduce and see...

								Honza
-- 
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR