rcu: Update documentation to flag RCU_BOOST trace information

Call out the RCU_TRACE information that is provided only in kernels
built with RCU_BOOST.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/Documentation/RCU/trace.txt b/Documentation/RCU/trace.txt
index 8173cec473aa..a67af0a39ded 100644
--- a/Documentation/RCU/trace.txt
+++ b/Documentation/RCU/trace.txt
@@ -184,10 +184,14 @@ o	"kt" is the per-CPU kernel-thread state.  The digit preceding
         The number after the final slash is the CPU that the kthread
         is actually running on.
 
+        This field is displayed only for CONFIG_RCU_BOOST kernels.
+
 o       "ktl" is the low-order 16 bits (in hexadecimal) of the count of
         the number of times that this CPU's per-CPU kthread has gone
         through its loop servicing invoke_rcu_cpu_kthread() requests.
 
+        This field is displayed only for CONFIG_RCU_BOOST kernels.
+
 o       "b" is the batch limit for this CPU.  If more than this number
         of RCU callbacks is ready to invoke, then the remainder will
         be deferred.