From mboxrd@z Thu Jan  1 00:00:00 1970
From: John Kacur <jkacur@redhat.com>
Subject: Re: [PATCH 1/2] do-not-allow-prio-less-than-one-in-cyclictest.patch
Date: Sun, 7 Mar 2010 23:37:29 +0100
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	 <20100307204241.033320249@osadl.org>
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Cc: Clark Williams <williams@redhat.com>,
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To: Carsten Emde <C.Emde@osadl.org>
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On Sun, Mar 7, 2010 at 9:39 PM, Carsten Emde <C.Emde@osadl.org> wrote:
> If not in SMP testing mode, the priority may go below 1, if the speci=
fied
> priority is lower than the number of threads, e.g.
> # cyclictest -p2 -t3
> T: 0 (21970) P: 2 [..]
> T: 1 (21971) P: 1 [..]
> T: 2 (21972) P: 0 [..]
>
> Do not allow priority to go below 1.
>
> Signed-off-by: Carsten Emde <C.Emde@osadl.org>
>
> Index: rt-tests/src/cyclictest/cyclictest.c
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> --- rt-tests.orig/src/cyclictest/cyclictest.c
> +++ rt-tests/src/cyclictest/cyclictest.c
> @@ -1304,7 +1304,7 @@ int main(int argc, char **argv)
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0}
>
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0par->prio =3D priority;
> - =A0 =A0 =A0 =A0 =A0 =A0 =A0 if (!sameprio)
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 if (priority > 1 && !sameprio)
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0priority--;
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 if =A0 =A0 =A0(priority && policy <=3D=
 1) par->policy =3D SCHED_FIFO;
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 else if (priority && policy =3D=3D 2)=
 par->policy =3D SCHED_RR;
>
> --

I'm not sure about this, why not allow a priority below 1? The code
below properly sets the third thead to SCHED_OTHER.
I could imagine wanting to test that too. If you don't want to go
below 1 then just set a higher prio, p3 in the scenario you
showed.

Thanks.
John
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