Re: [PATCH rcu 0/6] Grace-period memory-barrier adjustments for v6.11

From: Paul E. McKenney
Date: Wed Jun 12 2024 - 10:47:45 EST


On Wed, Jun 12, 2024 at 03:12:07PM +0530, Neeraj Upadhyay wrote:
> On Tue, Jun 04, 2024 at 03:26:46PM -0700, Paul E. McKenney wrote:
> > Hello!
> >
> > This series removes redundant memory barriers from the grace-period
> > code paths:
> >
> > 1. Remove full ordering on second EQS snapshot, courtesy of Frederic
> > Weisbecker.
> >
> > 2. Remove superfluous full memory barrier upon first EQS snapshot,
> > courtesy of Frederic Weisbecker.
> >
> > 3. rcu/exp: Remove superfluous full memory barrier upon first EQS
> > snapshot, courtesy of Frederic Weisbecker.
> >
> > 4. Remove full memory barrier on boot time eqs sanity check,
> > courtesy of Frederic Weisbecker.
> >
> > 5. Remove full memory barrier on RCU stall printout, courtesy of
> > Frederic Weisbecker.
> >
> > 6. rcu/exp: Remove redundant full memory barrier at the end of GP,
> > courtesy of Frederic Weisbecker.
> >
>
> Reviewed-by: Neeraj Upadhyay <neeraj.upadhyay@xxxxxxxxxx>

I will apply yours and Boqun's tag on the next rebase, thank you both!

Thanx, Paul

> > ------------------------------------------------------------------------
> >
> > b/Documentation/RCU/Design/Memory-Ordering/Tree-RCU-Memory-Ordering.rst | 6 +--
> > b/kernel/rcu/tree.c | 2 -
> > b/kernel/rcu/tree_exp.h | 8 +++-
> > b/kernel/rcu/tree_stall.h | 4 +-
> > kernel/rcu/tree.c | 19 +++-------
> > kernel/rcu/tree_exp.h | 8 +++-
> > 6 files changed, 26 insertions(+), 21 deletions(-)