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| author |   Ankur Arora <ankur.a.arora@oracle.com> | 2024-12-12 20:06:58 -0800 |
|---|---|---|
| committer |   Boqun Feng <boqun.feng@gmail.com> | 2025-03-04 18:46:47 -0800 |
| commit | 8437bb84bc554fed7a716408cbb2b0e3bd13356e (patch) | |
| tree | cc11071dbc0d21580f686aa20775059a98216346 | |
| parent | rcutorture: Update ->extendables check for lazy preemption (diff) | |
| download | wireguard-linux-8437bb84bc554fed7a716408cbb2b0e3bd13356e.tar.xz wireguard-linux-8437bb84bc554fed7a716408cbb2b0e3bd13356e.zip | |
rcu: limit PREEMPT_RCU configurations
PREEMPT_LAZY can be enabled stand-alone or alongside PREEMPT_DYNAMIC
which allows for dynamic switching of preemption models.
The choice of PREEMPT_RCU or not, however, is fixed at compile time.
Given that PREEMPT_RCU makes some trade-offs to optimize for latency
as opposed to throughput, configurations with limited preemption
might prefer the stronger forward-progress guarantees of PREEMPT_RCU=n.
Accordingly, explicitly limit PREEMPT_RCU=y to the latency oriented
preemption models: PREEMPT, PREEMPT_RT, and the runtime configurable
model PREEMPT_DYNAMIC.
This means the throughput oriented models, PREEMPT_NONE,
PREEMPT_VOLUNTARY, and PREEMPT_LAZY will run with PREEMPT_RCU=n.
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Diffstat (limited to '')
| -rw-r--r-- | kernel/rcu/Kconfig | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/rcu/Kconfig b/kernel/rcu/Kconfig index e2206f3a070c..dd6251678e99 100644 --- a/kernel/rcu/Kconfig +++ b/kernel/rcu/Kconfig @@ -18,7 +18,7 @@ config TREE_RCU config PREEMPT_RCU bool - default y if PREEMPTION + default y if (PREEMPT || PREEMPT_RT || PREEMPT_DYNAMIC) select TREE_RCU help This option selects the RCU implementation that is |