Re: [v2,04/12] rcutorture: Make torture.sh --do-rt use CONFIG_PREEMPT_RT
From: Paul E. McKenney
Date: Wed Apr 02 2025 - 15:17:43 EST
On Wed, Apr 02, 2025 at 12:19:13PM -0400, Joel Fernandes wrote:
> Hello,
>
> On Wed, 2 Apr 2025 16:17:06 GMT, Sebastian Andrzej Siewior wrote:
> > On 2025-03-31 14:03:06 [-0700], Paul E. McKenney wrote:
> > > The torture.sh --do-rt command-line parameter is intended to mimic -rt
> > > kernels. Now that CONFIG_PREEMPT_RT is upstream, this commit makes this
> > > mimicking more precise.
> > >
> > > Note that testing of RCU priority boosting is disabled in favor
> > > of forward-progress testing of RCU callbacks. If it turns out to be
> > > possible to make kernels built with CONFIG_PREEMPT_RT=y to tolerate
> > > testing of both, both will be enabled.
> >
> > Not sure what you point at here: You can build a PREEMPT_RT kernel and
> > RCU boosting is enabled by default. You could disable it if needed.
>
> Yeah, RCU_BOOST has default y if PREEMPT_RT.
>
> Paul, should we be disabling it in the --do-rt script?
You should have a "rcutorture.test_boost=0" from f2ac55968df2
("rcutorture: Make torture.sh --do-rt use CONFIG_PREEMPT_RT").
Plus I just now made additional adjustments based on Sebastian Siewior's
feedback. He is likely to have additional feedback, so this is currently
a "squash!" commit in my tree.
Thanx, Paul