Re: [PATCH 08/10] rcu: Allow to deactivate nocb on a CPU

From: Frederic Weisbecker
Date: Thu Jun 04 2020 - 09:14:14 EST


On Tue, May 26, 2020 at 05:20:17PM -0400, Joel Fernandes wrote:
> On Wed, May 13, 2020 at 06:47:12PM +0200, Frederic Weisbecker wrote:
> > Allow a CPU's rdp to quit the callback offlined mode.
>
> nit: s/offlined/offloaded/ ?

Oh, looks like I did that everywhere :)

>
> > The switch happens on the target with IRQs disabled and rdp->nocb_lock
> > held to avoid races between local callbacks handling and kthread
> > offloaded callbacks handling.
> > nocb_cb kthread is first parked to avoid any future race with
> > concurrent rcu_do_batch() executions. Then the cblist is set to offloaded
> > so that the nocb_gp kthread ignores this rdp.
>
> nit: you mean cblist is set to non-offloaded mode right?

Ah right!

> > +static void __rcu_nocb_rdp_deoffload(struct rcu_data *rdp)
> > +{
> > + unsigned long flags;
> > + struct rcu_node *rnp = rdp->mynode;
> > +
> > + printk("De-offloading %d\n", rdp->cpu);
>
> nit: s/printk/pr_debug/ ?

Ok.

Thanks!