Re: [patch] RCU: introduce rcu_soon_pending() interface

[Heiko Carstens <heiko.carstens@de.ibm.com>]

> > @@ -485,6 +485,14 @@ int rcu_pending(int cpu)
> >  		__rcu_pending(&rcu_bh_ctrlblk, &per_cpu(rcu_bh_data, cpu));
> >  }
> >  
> > +int rcu_soon_pending(int cpu)
> > +{
> > +	struct rcu_data *rdp = &per_cpu(rcu_data, cpu);
> > +	struct rcu_data *rdp_bh = &per_cpu(rcu_bh_data, cpu);
> > +
> > +	return (!!rdp->curlist || !!rdp_bh->curlist);
> > +}
> 
> This patch sets my nerves a-jangling.
> 
> What are the units of soonness?  It's awfully waffly.  Can we specify this
> more tightly?
> 
> Neither rcu_pending() nor rcu_soon_pending() are commented or documented. 
> Pity the poor user trying to work out what they do, and how they differ. 
> They're global symbols and they form part of the RCU API - they should be
> kernel docified, please.
> 
> There's probably a reason why neither of these symbols are exported to
> modules.  Once they're actually documented I mught be able to work out what
> that reason is ;)

Maybe rcu_batch_pending() would be a better name for rcu_soon_pending(). Also
rcu_batch_in_work() would be a more descriptive name for rcu_pending() as far
as I can tell.
Actually I was hoping for a better solution from the rcu experts, since I
don't like this too, but couldn't find something better.