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Date: Thu, 22 Feb 2024 16:26:18 -0800
From: "Paul E. McKenney" <paulmck@kernel.org>
To: rcu@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, kernel-team@meta.com, rostedt@goodmis.org,
	ankur.a.arora@oracle.com, tglx@linutronix.de, mark.rutland@arm.com
Subject: [PATCH rcu 0/4] Refactor TASKS_RCU for lazy preemption
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Hello!

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.

						Thanx, Paul

------------------------------------------------------------------------

 arch/Kconfig         |    4 ++--
 kernel/bpf/Kconfig   |    2 +-
 kernel/rcu/Kconfig   |    6 +++++-
 kernel/trace/Kconfig |    4 ++--
 4 files changed, 10 insertions(+), 6 deletions(-)