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McKenney" To: Neeraj Upadhyay Cc: rcu@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@meta.com, rostedt@goodmis.org Subject: Re: [PATCH rcu 0/6] Grace-period memory-barrier adjustments for v6.11 Message-ID: <39815e48-a035-4701-9a88-f3b753551b28@paulmck-laptop> Reply-To: paulmck@kernel.org References: <81f4e616-8125-4934-a8e2-fd5beae90995@paulmck-laptop> <20240612094207.GA418202@neeraj.linux> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240612094207.GA418202@neeraj.linux> 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 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(-)