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authorChris Wilson <chris@chris-wilson.co.uk>2016-12-01 11:47:05 +0000
committerIngo Molnar <mingo@kernel.org>2017-01-14 11:37:14 +0100
commit0186a6cbdc6287fde65858e5d9c714dc167b8ace (patch)
tree7f9d7eac00704e67959e5786c7d2b94cecf739a6 /kernel/locking
parentaf2e859edd477fa1ea3d1d106f41a595cff3d162 (diff)
locking/ww_mutex: Add ww_mutex to locktorture test
Although ww_mutexes degenerate into mutexes, it would be useful to torture the deadlock handling between multiple ww_mutexes in addition to torturing the regular mutexes. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Maarten Lankhorst <dev@mblankhorst.nl> Cc: Nicolai Hähnle <nhaehnle@gmail.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20161201114711.28697-3-chris@chris-wilson.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/locking')
-rw-r--r--kernel/locking/locktorture.c73
1 files changed, 73 insertions, 0 deletions
diff --git a/kernel/locking/locktorture.c b/kernel/locking/locktorture.c
index f8c5af52a131..9bffedd82884 100644
--- a/kernel/locking/locktorture.c
+++ b/kernel/locking/locktorture.c
@@ -372,6 +372,78 @@ static struct lock_torture_ops mutex_lock_ops = {
.name = "mutex_lock"
};
+#include <linux/ww_mutex.h>
+static DEFINE_WW_CLASS(torture_ww_class);
+static DEFINE_WW_MUTEX(torture_ww_mutex_0, &torture_ww_class);
+static DEFINE_WW_MUTEX(torture_ww_mutex_1, &torture_ww_class);
+static DEFINE_WW_MUTEX(torture_ww_mutex_2, &torture_ww_class);
+
+static int torture_ww_mutex_lock(void)
+__acquires(torture_ww_mutex_0)
+__acquires(torture_ww_mutex_1)
+__acquires(torture_ww_mutex_2)
+{
+ LIST_HEAD(list);
+ struct reorder_lock {
+ struct list_head link;
+ struct ww_mutex *lock;
+ } locks[3], *ll, *ln;
+ struct ww_acquire_ctx ctx;
+
+ locks[0].lock = &torture_ww_mutex_0;
+ list_add(&locks[0].link, &list);
+
+ locks[1].lock = &torture_ww_mutex_1;
+ list_add(&locks[1].link, &list);
+
+ locks[2].lock = &torture_ww_mutex_2;
+ list_add(&locks[2].link, &list);
+
+ ww_acquire_init(&ctx, &torture_ww_class);
+
+ list_for_each_entry(ll, &list, link) {
+ int err;
+
+ err = ww_mutex_lock(ll->lock, &ctx);
+ if (!err)
+ continue;
+
+ ln = ll;
+ list_for_each_entry_continue_reverse(ln, &list, link)
+ ww_mutex_unlock(ln->lock);
+
+ if (err != -EDEADLK)
+ return err;
+
+ ww_mutex_lock_slow(ll->lock, &ctx);
+ list_move(&ll->link, &list);
+ }
+
+ ww_acquire_fini(&ctx);
+ return 0;
+}
+
+static void torture_ww_mutex_unlock(void)
+__releases(torture_ww_mutex_0)
+__releases(torture_ww_mutex_1)
+__releases(torture_ww_mutex_2)
+{
+ ww_mutex_unlock(&torture_ww_mutex_0);
+ ww_mutex_unlock(&torture_ww_mutex_1);
+ ww_mutex_unlock(&torture_ww_mutex_2);
+}
+
+static struct lock_torture_ops ww_mutex_lock_ops = {
+ .writelock = torture_ww_mutex_lock,
+ .write_delay = torture_mutex_delay,
+ .task_boost = torture_boost_dummy,
+ .writeunlock = torture_ww_mutex_unlock,
+ .readlock = NULL,
+ .read_delay = NULL,
+ .readunlock = NULL,
+ .name = "ww_mutex_lock"
+};
+
#ifdef CONFIG_RT_MUTEXES
static DEFINE_RT_MUTEX(torture_rtmutex);
@@ -793,6 +865,7 @@ static int __init lock_torture_init(void)
&spin_lock_ops, &spin_lock_irq_ops,
&rw_lock_ops, &rw_lock_irq_ops,
&mutex_lock_ops,
+ &ww_mutex_lock_ops,
#ifdef CONFIG_RT_MUTEXES
&rtmutex_lock_ops,
#endif