[PATCH v3 tip/core/rcu 36/40] srcutorture: Print Tiny SRCU reader statistics

From: Paul E. McKenney
Date: Wed Apr 19 2017 - 13:08:16 EST


The srcu_torture_stats() function is adapted to the specific srcu_struct
layout traditionally used by SRCU. This commit therefore adds support
for Tiny SRCU.

Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
---
kernel/rcu/rcutorture.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 98591e16db1a..9cbb8a7b909d 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -559,11 +559,12 @@ static void srcu_torture_barrier(void)

static void srcu_torture_stats(void)
{
-#ifdef CONFIG_TREE_SRCU
- int cpu;
- int idx = srcu_ctlp->completed & 0x1;
+ int __maybe_unused cpu;
+ int idx;

- pr_alert("%s%s per-CPU(idx=%d):",
+#ifdef CONFIG_TREE_SRCU
+ idx = srcu_ctlp->completed & 0x1;
+ pr_alert("%s%s Tree SRCU per-CPU(idx=%d):",
torture_type, TORTURE_FLAG, idx);
for_each_possible_cpu(cpu) {
unsigned long l0, l1;
@@ -588,6 +589,12 @@ static void srcu_torture_stats(void)
pr_cont(" %d(%ld,%ld)", cpu, c0, c1);
}
pr_cont("\n");
+#elif defined(CONFIG_TINY_SRCU)
+ idx = READ_ONCE(srcu_ctlp->srcu_idx) & 0x1;
+ pr_alert("%s%s Tiny SRCU per-CPU(idx=%d): (%d,%d)\n",
+ torture_type, TORTURE_FLAG, idx,
+ READ_ONCE(srcu_ctlp->srcu_lock_nesting[!idx]),
+ READ_ONCE(srcu_ctlp->srcu_lock_nesting[idx]));
#endif
}

--
2.5.2