[PATCH tip/core/rcu 09/24] rcutorture: Make rcuperf collect expedited event-trace data

[Paul E. McKenney]

This commit enables ftrace in the rcuperf TREE kernel build and adds
an ftrace_dump() at the end of rcuperf processing.  This data will be
used to measure the actual durations of the expedited grace periods
without the added delays inherent in the kernel-module measurements.

Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
---
 kernel/rcu/rcuperf.c                                    | 1 +
 tools/testing/selftests/rcutorture/configs/rcuperf/TREE | 1 +
 2 files changed, 2 insertions(+)

diff --git a/kernel/rcu/rcuperf.c b/kernel/rcu/rcuperf.c
index e18d016a9888..12561f96f0a2 100644
--- a/kernel/rcu/rcuperf.c
+++ b/kernel/rcu/rcuperf.c
@@ -404,6 +404,7 @@ rcu_perf_writer(void *arg)
 				 perf_type, me, MIN_MEAS);
 			if (atomic_inc_return(&n_rcu_perf_writer_finished) >=
 			    nrealwriters) {
+				rcu_ftrace_dump(DUMP_ALL);
 				PERFOUT_STRING("Test complete");
 				t_rcu_perf_writer_finished = t;
 				if (gp_exp) {
diff --git a/tools/testing/selftests/rcutorture/configs/rcuperf/TREE b/tools/testing/selftests/rcutorture/configs/rcuperf/TREE
index 614e107f6db5..a312f671a29a 100644
--- a/tools/testing/selftests/rcutorture/configs/rcuperf/TREE
+++ b/tools/testing/selftests/rcutorture/configs/rcuperf/TREE
@@ -17,3 +17,4 @@ CONFIG_PROVE_LOCKING=n
 CONFIG_RCU_BOOST=n
 CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
 CONFIG_RCU_EXPERT=y
+CONFIG_RCU_TRACE=y
-- 
2.5.2