Re: [PATCH tip/core/rcu 1/2] doc/kprobes: Update obsolete RCU update functions

From: Paul E. McKenney
Date: Wed Mar 27 2019 - 16:22:42 EST


On Wed, Mar 27, 2019 at 12:21:12PM +0900, Masami Hiramatsu wrote:
> On Tue, 26 Mar 2019 16:00:49 -0700
> "Paul E. McKenney" <paulmck@xxxxxxxxxxxxx> wrote:
>
> > The RCU flavors have been consolidated, so this commit replaces mentions
> > of the now-obsolete synchronize_sched() function with synchronize_rcu().
>
> Thank you for updating!
>
> Acked-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>

Applied, thank you!

Thanx, Paul

> > Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxx>
> > Cc: "Naveen N. Rao" <naveen.n.rao@xxxxxxxxxxxxx>
> > Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@xxxxxxxxx>
> > Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
> > Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
> > Cc: Jonathan Corbet <corbet@xxxxxxx>
> > Cc: <linux-doc@xxxxxxxxxxxxxxx>
> > ---
> > Documentation/kprobes.txt | 6 +++---
> > 1 file changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/Documentation/kprobes.txt b/Documentation/kprobes.txt
> > index 10f4499e677c..ee60e519438a 100644
> > --- a/Documentation/kprobes.txt
> > +++ b/Documentation/kprobes.txt
> > @@ -243,10 +243,10 @@ Optimization
> > ^^^^^^^^^^^^
> >
> > The Kprobe-optimizer doesn't insert the jump instruction immediately;
> > -rather, it calls synchronize_sched() for safety first, because it's
> > +rather, it calls synchronize_rcu() for safety first, because it's
> > possible for a CPU to be interrupted in the middle of executing the
> > -optimized region [3]_. As you know, synchronize_sched() can ensure
> > -that all interruptions that were active when synchronize_sched()
> > +optimized region [3]_. As you know, synchronize_rcu() can ensure
> > +that all interruptions that were active when synchronize_rcu()
> > was called are done, but only if CONFIG_PREEMPT=n. So, this version
> > of kprobe optimization supports only kernels with CONFIG_PREEMPT=n [4]_.
> >
> > --
> > 2.17.1
> >
>
>
> --
> Masami Hiramatsu <mhiramat@xxxxxxxxxx>
>