summaryrefslogtreecommitdiffstats
path: root/debian/patches-rt/0267-rcu-Don-t-allow-to-change-rcu_normal_after_boot-on-R.patch
blob: 4aa1d5fb3d1df19af516e24e479bdea0df12110d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Mon, 24 Jun 2019 18:29:13 +0200
Subject: [PATCH 267/351] rcu: Don't allow to change rcu_normal_after_boot on
 RT
Origin: https://git.kernel.org/cgit/linux/kernel/git/rt/linux-stable-rt.git/commit?id=565e362156219f5a3f23c65e806e5954a72382ba

[ Upstream commit c6c058c10577815a2491ce661876cff00a4c3b15 ]

On RT rcu_normal_after_boot is enabled by default.
Don't allow to disable it on RT because the "expedited rcu" would
introduce latency spikes.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 kernel/rcu/update.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c
index 16d8dba23329..ed75addd3ccd 100644
--- a/kernel/rcu/update.c
+++ b/kernel/rcu/update.c
@@ -69,7 +69,9 @@ module_param(rcu_expedited, int, 0);
 extern int rcu_normal; /* from sysctl */
 module_param(rcu_normal, int, 0);
 static int rcu_normal_after_boot = IS_ENABLED(CONFIG_PREEMPT_RT_FULL);
+#ifndef CONFIG_PREEMPT_RT_FULL
 module_param(rcu_normal_after_boot, int, 0);
+#endif
 #endif /* #ifndef CONFIG_TINY_RCU */
 
 #ifdef CONFIG_DEBUG_LOCK_ALLOC