Re: [PATCH RFC v2 rcu 2/8] srcu: Create an srcu_read_lock_nmisafe() and srcu_read_unlock_nmisafe()

[Frederic Weisbecker <frederic@xxxxxxxxxx>]

On Sun, Oct 02, 2022 at 05:55:16PM +0200, Frederic Weisbecker wrote:
> On Thu, Sep 29, 2022 at 11:07:25AM -0700, Paul E. McKenney wrote:
> > @@ -1090,7 +1121,7 @@ static unsigned long srcu_gp_start_if_needed(struct srcu_struct *ssp,
> >  	int ss_state;
> >  
> >  	check_init_srcu_struct(ssp);
> > -	idx = srcu_read_lock(ssp);
> > +	idx = __srcu_read_lock_nmisafe(ssp);
> 
> Why do we need to force the atomic based version here (even if
> CONFIG_NEED_SRCU_NMI_SAFE=y)?

...even if CONFIG_NEED_SRCU_NMI_SAFE=n that is...