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[103.168.172.201]) by smtp.gmail.com with ESMTPSA id af79cd13be357-797a2b7f956sm186654985a.6.2024.06.11.22.21.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 11 Jun 2024 22:21:58 -0700 (PDT) Received: from compute5.internal (compute5.nyi.internal [10.202.2.45]) by mailfauth.nyi.internal (Postfix) with ESMTP id 2893D1200043; Wed, 12 Jun 2024 01:21:58 -0400 (EDT) Received: from mailfrontend2 ([10.202.2.163]) by compute5.internal (MEProxy); Wed, 12 Jun 2024 01:21:58 -0400 X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvledrfedufedgledvucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhepfffhvfevuffkfhggtggujgesthdtredttddtvdenucfhrhhomhepuehoqhhu nhcuhfgvnhhguceosghoqhhunhdrfhgvnhhgsehgmhgrihhlrdgtohhmqeenucggtffrrg htthgvrhhnpeehudfgudffffetuedtvdehueevledvhfelleeivedtgeeuhfegueeviedu ffeivdenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpe gsohhquhhnodhmvghsmhhtphgruhhthhhpvghrshhonhgrlhhithihqdeiledvgeehtdei gedqudejjeekheehhedvqdgsohhquhhnrdhfvghngheppehgmhgrihhlrdgtohhmsehfih igmhgvrdhnrghmvg X-ME-Proxy: Feedback-ID: iad51458e:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Wed, 12 Jun 2024 01:21:57 -0400 (EDT) Date: Tue, 11 Jun 2024 22:21:56 -0700 From: Boqun Feng To: "Paul E. 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: 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: Boqun Feng Regards, Boqun > 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(-) >