> The forcing of an expedited grace period is an expensive and very > RT-application unfriendly operation, as it forcibly preempts all running > tasks on CPUs which are preventing the gp from expiring. > > By default, as a policy decision, disable the expediting of grace > periods (after boot) on configurations which enable PREEMPT_RT_FULL. > > Suggested-by: Luiz Capitulino <lcapitulino@xxxxxxxxxx> > Signed-off-by: Julia Cartwright <julia@xxxxxx> > Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> In case it matters: Acked-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxx> Alternatively, any reason that I should not pull this into -rcu? Thanx, Paul > diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c > index f56c0fbdf22e..12027723abaf 100644 > --- a/kernel/rcu/update.c > +++ b/kernel/rcu/update.c > @@ -67,7 +67,7 @@ extern int rcu_expedited; /* from sysctl */ > module_param(rcu_expedited, int, 0); > extern int rcu_normal; /* from sysctl */ > module_param(rcu_normal, int, 0); > -static int rcu_normal_after_boot; > +static int rcu_normal_after_boot = IS_ENABLED(CONFIG_PREEMPT_RT_FULL); > module_param(rcu_normal_after_boot, int, 0); > #endif /* #ifndef CONFIG_TINY_RCU */ >
