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McKenney" 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: <20240612094207.GA418202@neeraj.linux> References: <81f4e616-8125-4934-a8e2-fd5beae90995@paulmck-laptop> 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: <81f4e616-8125-4934-a8e2-fd5beae90995@paulmck-laptop> 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 > 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(-)