Re: [PATCH v3 13/22] tracing: Remove regular RCU context for _rcuidle tracepoints (again)

Paul E. McKenney
2020-02-19T19:05:24Z

On Wed, Feb 19, 2020 at 01:00:12PM -0500, Steven Rostedt wrote:
> On Wed, 19 Feb 2020 09:40:25 -0800
> "Paul E. McKenney" <paulmck@kernel.org> wrote:
>
> > > Correct, and if rcuidle is not set, and this is a macro, the SRCU
> > > portion is compiled out.
> >
> > Sigh! Apologies for the noise!
> >
> > If we are using SRCU, we don't care whether or not RCU is watching. OK,
> > maybe finally catching up -- the whole point was use of RCU in other
> > tracing code, wasn't it?
>
> Some callbacks (namely perf) might use RCU, but then the callbacks
> need to make sure rcu is watching.

Got it, thank you!

Thanx, Paul