include/asm-x86/pgtable-2level.h: checkpatch cleanups - formatting only

[sfrench/cifs-2.6.git] / kernel / Kconfig.preempt

diff --git a/kernel/Kconfig.preempt b/kernel/Kconfig.preempt
index 0669b70fa6a3af35c4c67599575a8c2a12154fa4..9fdba03dc1fcd119c31274fb3590480aa1db9f05 100644 (file)
--- a/kernel/Kconfig.preempt
+++ b/kernel/Kconfig.preempt
@@ -52,8 +52,23 @@ config PREEMPT
 
 endchoice
 
+config PREEMPT_RCU
+       bool "Preemptible RCU"
+       depends on PREEMPT
+       default n
+       help
+         This option reduces the latency of the kernel by making certain
+         RCU sections preemptible. Normally RCU code is non-preemptible, if
+         this option is selected then read-only RCU sections become
+         preemptible. This helps latency, but may expose bugs due to
+         now-naive assumptions about each RCU read-side critical section
+         remaining on a given CPU through its execution.
+
+         Say N if you are unsure.
+
 config RCU_TRACE
        bool "Enable tracing for RCU - currently stats in debugfs"
+       depends on PREEMPT_RCU
        select DEBUG_FS
        default y
        help