Re: [PATCH] tracing, rcu: Remove no longer used trace event rcu_prep_idle

From: Paul E. McKenney
Date: Thu Oct 12 2017 - 18:46:25 EST


On Thu, Oct 12, 2017 at 06:32:39PM -0400, Steven Rostedt wrote:
> On Thu, 12 Oct 2017 15:26:45 -0700
> "Paul E. McKenney" <paulmck@xxxxxxxxxxxxxxxxxx> wrote:
>
> > On Thu, Oct 12, 2017 at 06:12:57PM -0400, Steven Rostedt wrote:
> > > From: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
> > >
> > > Commit c0f4dfd4f90 ("rcu: Make RCU_FAST_NO_HZ take advantage of
> > > numbered callbacks") removed the only instances of trace_rcu_prep_idle,
> > > but did not remove the TRACE_EVENT() that creates it. As defined trace
> > > events take up memory within the kernel even when they are not used,
> > > this is a waste of space. Remove the obsolete event.
> > >
> > > Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
> >
> > Good catch, queued for review and testing, thank you!
> >
> > Slight change in the context of the final hunk of the patch for -rcu,
> > updated version shown below.
>
> I now have a utility that complains when tracepoints are not used. But
> I'm working on getting this to work at build time and not run time. In
> the mean time, I might as well do some clean up ;-)

Well, I just today learned that I am not supposed to be using the %p
printk format option, so been doing a bit of cleaning here as well. ;-)

Thanx, Paul