Commit-ID: c22fb3807fd0a3bdd98c13c4d2190ab064e6c09d Gitweb: http://git.kernel.org/tip/c22fb3807fd0a3bdd98c13c4d2190ab064e6c09d Author: Chris Wilson <ch...@chris-wilson.co.uk> AuthorDate: Thu, 1 Dec 2016 11:47:07 +0000 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Sat, 14 Jan 2017 11:37:15 +0100
locking/ww_mutex: Add kselftests for ww_mutex AA deadlock detection Signed-off-by: Chris Wilson <ch...@chris-wilson.co.uk> Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> Cc: Andrew Morton <a...@linux-foundation.org> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Maarten Lankhorst <d...@mblankhorst.nl> Cc: Nicolai Hähnle <nhaeh...@gmail.com> Cc: Paul E. McKenney <paul...@linux.vnet.ibm.com> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Thomas Gleixner <t...@linutronix.de> Link: http://lkml.kernel.org/r/20161201114711.28697-5-ch...@chris-wilson.co.uk Signed-off-by: Ingo Molnar <mi...@kernel.org> --- kernel/locking/test-ww_mutex.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) diff --git a/kernel/locking/test-ww_mutex.c b/kernel/locking/test-ww_mutex.c index 472d5b1..835fa7a 100644 --- a/kernel/locking/test-ww_mutex.c +++ b/kernel/locking/test-ww_mutex.c @@ -118,6 +118,41 @@ static int test_mutex(void) return 0; } +static int test_aa(void) +{ + struct ww_mutex mutex; + struct ww_acquire_ctx ctx; + int ret; + + ww_mutex_init(&mutex, &ww_class); + ww_acquire_init(&ctx, &ww_class); + + ww_mutex_lock(&mutex, &ctx); + + if (ww_mutex_trylock(&mutex)) { + pr_err("%s: trylocked itself!\n", __func__); + ww_mutex_unlock(&mutex); + ret = -EINVAL; + goto out; + } + + ret = ww_mutex_lock(&mutex, &ctx); + if (ret != -EALREADY) { + pr_err("%s: missed deadlock for recursing, ret=%d\n", + __func__, ret); + if (!ret) + ww_mutex_unlock(&mutex); + ret = -EINVAL; + goto out; + } + + ret = 0; +out: + ww_mutex_unlock(&mutex); + ww_acquire_fini(&ctx); + return ret; +} + static int __init test_ww_mutex_init(void) { int ret; @@ -126,6 +161,10 @@ static int __init test_ww_mutex_init(void) if (ret) return ret; + ret = test_aa(); + if (ret) + return ret; + return 0; }
