Re: [PATCH RFC 3/9] RCU: Preemptible RCU

[Dipankar Sarma <dipankar@in.ibm.com>]

On Fri, Sep 21, 2007 at 12:17:21AM -0400, Steven Rostedt wrote:
> [ continued here from comment on patch 1]
> 
> On Mon, Sep 10, 2007 at 11:34:12AM -0700, Paul E. McKenney wrote:
> >  /* softirq mask and active fields moved to irq_cpustat_t in
> > diff -urpNa -X dontdiff linux-2.6.22-b-fixbarriers/include/linux/rcuclassic.h linux-2.6.22-c-preemptrcu/include/linux/rcuclassic.h
> > --- linux-2.6.22-b-fixbarriers/include/linux/rcuclassic.h	2007-08-22 14:42:23.000000000 -0700
> > +++ linux-2.6.22-c-preemptrcu/include/linux/rcuclassic.h	2007-08-22 15:21:06.000000000 -0700
> > @@ -142,8 +142,6 @@ extern int rcu_needs_cpu(int cpu);
> >  #define RCU_HEAD_INIT 	{ .next = NULL, .func = NULL }
> >  #define RCU_HEAD(head) struct rcu_head head = RCU_HEAD_INIT
> > @@ -218,10 +222,13 @@ extern void FASTCALL(call_rcu_bh(struct 
> >  /* Exported common interfaces */
> >  extern void synchronize_rcu(void);
> >  extern void rcu_barrier(void);
> > +extern long rcu_batches_completed(void);
> > +extern long rcu_batches_completed_bh(void);
> >
> 
> And here we put back rcu_batches_completed and rcu_batches_completed_bh
> from rcuclassic.h to rcupdate.h ;-)

Good questions :) I can't remember why I did this - probably because
I was breaking up into classic and preemptible RCU in incremental
patches with the goal that the break-up patch can be merged
before the rcu-preempt patches. IIRC, I had to make *batches_completed*()
a common RCU API later on.

Thanks
Dipankar