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

From: Neeraj Upadhyay
Date: Wed Jun 12 2024 - 05:42:33 EST


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>

> 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(-)