Messages in this thread | | | Date | Fri, 13 Jan 2023 09:44:35 +0100 | From | Petr Mladek <> | Subject | Re: [PATCH] kallsyms: Fix scheduling with interrupts disabled in self-test |
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On Thu 2023-01-12 10:24:43, Luis Chamberlain wrote: > On Thu, Jan 12, 2023 at 08:54:26PM +1000, Nicholas Piggin wrote: > > kallsyms_on_each* may schedule so must not be called with interrupts > > disabled. The iteration function could disable interrupts, but this > > also changes lookup_symbol() to match the change to the other timing > > code. > > > > Reported-by: Erhard F. <erhard_f@mailbox.org> > > Link: https://lore.kernel.org/all/bug-216902-206035@https.bugzilla.kernel.org%2F/ > > Reported-by: kernel test robot <oliver.sang@intel.com> > > Link: https://lore.kernel.org/oe-lkp/202212251728.8d0872ff-oliver.sang@intel.com > > Fixes: 30f3bb09778d ("kallsyms: Add self-test facility") > > Signed-off-by: Nicholas Piggin <npiggin@gmail.com> > > --- > > Thanks Nicholas! > > Petr had just suggested removing this aspect of the selftests, the performance > test as its specific to the config, it doesn't run many times to get an > average and odd things on a system can create different metrics. Zhen Lei > had given up on fixing it and has a patch to instead remove this part of > the selftest. > > I still find value in keeping it, but Petr, would like your opinion on > this fix, if we were to keep it.
I am fine with this fix.
It increases a risk of possible inaccuracy of the measured time. It would count also time spent on unrelated interrupts and eventual rescheduling.
Anyway, it is safe at least. I was against the previous attempts to fix this problem because they might have caused problems for the rest of the system.
Best Regards, Petr
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