[PATCH v3 3/4] locktorture: Add nested locking to rtmutex torture tests

John Stultz
2023-02-06T21:06:18Z

This patch adds randomized nested locking to the rtmutex torture
tests. Additionally it adds LOCK09 config files for testing
rtmutexes with nested locking.

Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: John Stultz <jstultz@google.com>
---
v2:
* Add LOCK09 config file suggested by Paul McKenney
v3:
* Minor commit message tweaks and naming changes
suggested by Davidlohr Bueso
---
kernel/locking/locktorture.c | 35 +++++++++++++++++++
.../selftests/rcutorture/configs/lock/CFLIST | 1 +
.../selftests/rcutorture/configs/lock/LOCK09 | 6 ++++
.../rcutorture/configs/lock/LOCK09.boot | 1 +
4 files changed, 43 insertions(+)
create mode 100644 tools/testing/selftests/rcutorture/configs/lock/LOCK09
create mode 100644 tools/testing/selftests/rcutorture/configs/lock/LOCK09.boot

diff --git a/kernel/locking/locktorture.c b/kernel/locking/locktorture.c
index 8a08c004aa80..fd8b2b007c26 100644
--- a/kernel/locking/locktorture.c
+++ b/kernel/locking/locktorture.c
@@ -506,6 +506,28 @@ static struct lock_torture_ops ww_mutex_lock_ops = {

#ifdef CONFIG_RT_MUTEXES
static DEFINE_RT_MUTEX(torture_rtmutex);
+static struct rt_mutex torture_nested_rtmutexes[MAX_NESTED_LOCKS];
+static struct lock_class_key nested_rtmutex_keys[MAX_NESTED_LOCKS];
+
+static void torture_rtmutex_init(void)
+{
+ int i;
+
+ for (i = 0; i < MAX_NESTED_LOCKS; i++)
+ __rt_mutex_init(&torture_nested_rtmutexes[i], __func__,
+ &nested_rtmutex_keys[i]);
+}
+
+static int torture_rtmutex_nested_lock(int tid __maybe_unused,
+ u32 lockset)
+{
+ int i;
+
+ for (i = 0; i < nested_locks; i++)
+ if (lockset & (1 << i))
+ rt_mutex_lock(&torture_nested_rtmutexes[i]);
+ return 0;
+}

static int torture_rtmutex_lock(int tid __maybe_unused)
__acquires(torture_rtmutex)
@@ -570,11 +592,24 @@ __releases(torture_rtmutex)
rt_mutex_unlock(&torture_rtmutex);
}

+static void torture_rtmutex_nested_unlock(int tid __maybe_unused,
+ u32 lockset)
+{
+ int i;
+
+ for (i = nested_locks - 1; i >= 0; i--)
+ if (lockset & (1 << i))
+ rt_mutex_unlock(&torture_nested_rtmutexes[i]);
+}
+
static struct lock_torture_ops rtmutex_lock_ops = {
+ .init = torture_rtmutex_init,
+ .nested_lock = torture_rtmutex_nested_lock,
.writelock = torture_rtmutex_lock,
.write_delay = torture_rtmutex_delay,
.task_boost = torture_rtmutex_boost,
.writeunlock = torture_rtmutex_unlock,
+ .nested_unlock = torture_rtmutex_nested_unlock,
.readlock = NULL,
.read_delay = NULL,
.readunlock = NULL,
diff --git a/tools/testing/selftests/rcutorture/configs/lock/CFLIST b/tools/testing/selftests/rcutorture/configs/lock/CFLIST
index a48bba0d35a6..28e23d05d5a5 100644
--- a/tools/testing/selftests/rcutorture/configs/lock/CFLIST
+++ b/tools/testing/selftests/rcutorture/configs/lock/CFLIST
@@ -6,3 +6,4 @@ LOCK05
LOCK06
LOCK07
LOCK08
+LOCK09
diff --git a/tools/testing/selftests/rcutorture/configs/lock/LOCK09 b/tools/testing/selftests/rcutorture/configs/lock/LOCK09
new file mode 100644
index 000000000000..1d1da1477fc3
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/configs/lock/LOCK09
@@ -0,0 +1,6 @@
+CONFIG_SMP=y
+CONFIG_NR_CPUS=4
+CONFIG_HOTPLUG_CPU=y
+CONFIG_PREEMPT_NONE=n
+CONFIG_PREEMPT_VOLUNTARY=n
+CONFIG_PREEMPT=y
diff --git a/tools/testing/selftests/rcutorture/configs/lock/LOCK09.boot b/tools/testing/selftests/rcutorture/configs/lock/LOCK09.boot
new file mode 100644
index 000000000000..fd5eff148a93
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/configs/lock/LOCK09.boot
@@ -0,0 +1 @@
+locktorture.torture_type=rtmutex_lock locktorture.nested_locks=8
--
2.39.1.519.gcb327c4b5f-goog