From 095031052b4c03a7c8ffa51cbab031e442c4f8b7 Mon Sep 17 00:00:00 2001
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Date: Thu, 31 Jan 2008 22:45:22 +0100
Subject: [PATCH] RCU: add help text for "RCU implementation type"

This patch supplies help text for the "RCU implementation type"
kernel configuration choice.

Reported-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 init/Kconfig | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/init/Kconfig b/init/Kconfig
index 0d0bbf218f1f..dcc96a8c8c69 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -775,6 +775,14 @@ config PREEMPT_NOTIFIERS
 choice
 	prompt "RCU implementation type:"
 	default CLASSIC_RCU
+	help
+	  This allows you to choose either the classic RCU implementation
+	  that is designed for best read-side performance on non-realtime
+	  systems, or the preemptible RCU implementation for best latency
+	  on realtime systems.  Note that some kernel preemption modes
+	  will restrict your choice.
+
+	  Select the default if you are unsure.
 
 config CLASSIC_RCU
 	bool "Classic RCU"
-- 
2.20.1