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McKenney" Cc: rcu@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@meta.com, rostedt@goodmis.org, ankur.a.arora@oracle.com, tglx@linutronix.de Subject: Re: [PATCH rcu 0/4] Refactor TASKS_RCU for lazy preemption Message-ID: References: <8c938bd5-6d62-4eff-9289-13b0d7ae8e17@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: <8c938bd5-6d62-4eff-9289-13b0d7ae8e17@paulmck-laptop> On Thu, Feb 22, 2024 at 04:26:18PM -0800, Paul E. McKenney wrote: > Hello! Hi! > This series refactors the NEED_TASKS_RCU option so that the conditional > processing is in one place in kernel/rcu/Kconfig. This makes it easier > to make sure that Tasks RCU is enabled in PREEMPT_AUTO kernels, given > that such kernels are preemptible, even if only lazily so. After all, > it takes only one lazy preemption from a trampoline to significantly > degrade your kernel's actuarial statistics. > > 1. Create NEED_TASKS_RCU to factor out enablement logic. > > 2. Select new NEED_TASKS_RCU Kconfig option. > > 3. Select new NEED_TASKS_RCU Kconfig option. > > 4. Select new NEED_TASKS_RCU Kconfig option. For the series: Acked-by: Mark Rutland Mark.