> Since it is no longer invoked from the softirq people run into OOM more > often if the priority of the RCU thread is too low. Making boosting > default on RT should help in those case and it can be switched off if > someone knows better. > > Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> > > diff --git a/kernel/rcu/Kconfig b/kernel/rcu/Kconfig > index 644264be90f0..0be2c96fb640 100644 > --- a/kernel/rcu/Kconfig > +++ b/kernel/rcu/Kconfig > @@ -36,7 +36,7 @@ config TINY_RCU > > config RCU_EXPERT > bool "Make expert-level adjustments to RCU configuration" > - default n > + default y if PREEMPT_RT_FULL Would it work to leave this as is, and ... > help > This option needs to be enabled if you wish to make > expert-level adjustments to RCU configuration. By default, > @@ -191,7 +191,7 @@ config RCU_FAST_NO_HZ > config RCU_BOOST > bool "Enable RCU priority boosting" > depends on RT_MUTEXES && PREEMPT_RCU && RCU_EXPERT ... make the above line instead be: depends on (RT_MUTEXES && PREEMPT_RCU && RCU_EXPERT) || PREEMPT_RT_FULL Or am I missing something? I agree that the risk might currently seem small, but if Linus ever starts building PREEMPT_RT_FULL kernels, I really really do not want RCU_EXPERT to be set. ;-) Thanx, Paul > - default n > + default y if PREEMPT_RT_FULL > help > This option boosts the priority of preempted RCU readers that > block the current preemptible RCU grace period for too long.
