On Thu, Jun 3, 2021 at 4:36 AM kernel test robot <oliver.sang@xxxxxxxxx> wrote: > > > > Greeting, > > FYI, we noticed a 32.2% improvement of stress-ng.fanotify.ops_per_sec due to commit: > > > commit: a8b98c808eab3ec8f1b5a64be967b0f4af4cae43 ("fanotify: fix permission model of unprivileged group") > https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master > > I guess now we know what caused the reported regression: https://lore.kernel.org/lkml/20210511124632.GL24154@xxxxxxxxxxxxxx/ I didn't know that capable() is so significant. FWIW, here is a link to the test code: https://github.com/ColinIanKing/stress-ng/blob/master/stress-fanotify.c#L474 It creates events in a loop by child process while the parent process reads the generated events in a loop (on two different fanotify groups). Thanks, Amir.