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[66.111.4.228]) by smtp.gmail.com with ESMTPSA id s12-20020a05620a16ac00b00783949e7817sm208651qkj.92.2024.01.25.19.59.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 25 Jan 2024 19:59:28 -0800 (PST) Received: from compute3.internal (compute3.nyi.internal [10.202.2.43]) by mailauth.nyi.internal (Postfix) with ESMTP id 6F9B027C005B; Thu, 25 Jan 2024 22:59:28 -0500 (EST) Received: from mailfrontend2 ([10.202.2.163]) by compute3.internal (MEProxy); Thu, 25 Jan 2024 22:59:28 -0500 X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvkedrvdeliedgieefucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhephffvvefufffkofgjfhgggfestdekredtredttdenucfhrhhomhepuehoqhhu nhcuhfgvnhhguceosghoqhhunhdrfhgvnhhgsehgmhgrihhlrdgtohhmqeenucggtffrrg htthgvrhhnpeegleejiedthedvheeggfejveefjeejkefgveffieeujefhueeigfegueeh geeggfenucevlhhushhtvghrufhiiigvpedvnecurfgrrhgrmhepmhgrihhlfhhrohhmpe gsohhquhhnodhmvghsmhhtphgruhhthhhpvghrshhonhgrlhhithihqdeiledvgeehtdei gedqudejjeekheehhedvqdgsohhquhhnrdhfvghngheppehgmhgrihhlrdgtohhmsehfih igmhgvrdhnrghmvg X-ME-Proxy: Feedback-ID: iad51458e:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Thu, 25 Jan 2024 22:59:27 -0500 (EST) From: Boqun Feng To: linux-kernel@vger.kernel.org, rcu@vger.kernel.org, linux-doc@vger.kernel.org Cc: Jonathan Corbet , "Paul E. McKenney" , Frederic Weisbecker , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Boqun Feng , Steven Rostedt , Mathieu Desnoyers , Lai Jiangshan , Zqiang Subject: [PATCH 8/8] doc: Update checklist.rst discussion of callback execution Date: Thu, 25 Jan 2024 19:58:11 -0800 Message-ID: <20240126035816.3129296-9-boqun.feng@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240126035816.3129296-1-boqun.feng@gmail.com> References: <20240126035816.3129296-1-boqun.feng@gmail.com> Precedence: bulk X-Mailing-List: rcu@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: "Paul E. McKenney" This commit completes the list of call_rcu*() functions that are not guaranteed to have their callbacks executing on the same CPU. While in the area, fix an unrelated typo. Signed-off-by: Paul E. McKenney --- Documentation/RCU/checklist.rst | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) diff --git a/Documentation/RCU/checklist.rst b/Documentation/RCU/checklist.rst index addd5c1547a4..3e6407de231c 100644 --- a/Documentation/RCU/checklist.rst +++ b/Documentation/RCU/checklist.rst @@ -383,16 +383,17 @@ over a rather long period of time, but improvements are always welcome! must use whatever locking or other synchronization is required to safely access and/or modify that data structure. - Do not assume that RCU callbacks will be executed on the same - CPU that executed the corresponding call_rcu() or call_srcu(). - For example, if a given CPU goes offline while having an RCU - callback pending, then that RCU callback will execute on some - surviving CPU. (If this was not the case, a self-spawning RCU - callback would prevent the victim CPU from ever going offline.) - Furthermore, CPUs designated by rcu_nocbs= might well *always* - have their RCU callbacks executed on some other CPUs, in fact, - for some real-time workloads, this is the whole point of using - the rcu_nocbs= kernel boot parameter. + Do not assume that RCU callbacks will be executed on + the same CPU that executed the corresponding call_rcu(), + call_srcu(), call_rcu_tasks(), call_rcu_tasks_rude(), or + call_rcu_tasks_trace(). For example, if a given CPU goes offline + while having an RCU callback pending, then that RCU callback + will execute on some surviving CPU. (If this was not the case, + a self-spawning RCU callback would prevent the victim CPU from + ever going offline.) Furthermore, CPUs designated by rcu_nocbs= + might well *always* have their RCU callbacks executed on some + other CPUs, in fact, for some real-time workloads, this is the + whole point of using the rcu_nocbs= kernel boot parameter. In addition, do not assume that callbacks queued in a given order will be invoked in that order, even if they all are queued on the