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Diffstat (limited to 'kernel/locking/test-ww_mutex.c')
-rw-r--r--kernel/locking/test-ww_mutex.c86
1 files changed, 65 insertions, 21 deletions
diff --git a/kernel/locking/test-ww_mutex.c b/kernel/locking/test-ww_mutex.c
index 3e82f449b4ff..d63ac411f367 100644
--- a/kernel/locking/test-ww_mutex.c
+++ b/kernel/locking/test-ww_mutex.c
@@ -16,6 +16,15 @@
static DEFINE_WD_CLASS(ww_class);
struct workqueue_struct *wq;
+#ifdef CONFIG_DEBUG_WW_MUTEX_SLOWPATH
+#define ww_acquire_init_noinject(a, b) do { \
+ ww_acquire_init((a), (b)); \
+ (a)->deadlock_inject_countdown = ~0U; \
+ } while (0)
+#else
+#define ww_acquire_init_noinject(a, b) ww_acquire_init((a), (b))
+#endif
+
struct test_mutex {
struct work_struct work;
struct ww_mutex mutex;
@@ -36,7 +45,7 @@ static void test_mutex_work(struct work_struct *work)
wait_for_completion(&mtx->go);
if (mtx->flags & TEST_MTX_TRY) {
- while (!ww_mutex_trylock(&mtx->mutex))
+ while (!ww_mutex_trylock(&mtx->mutex, NULL))
cond_resched();
} else {
ww_mutex_lock(&mtx->mutex, NULL);
@@ -109,19 +118,38 @@ static int test_mutex(void)
return 0;
}
-static int test_aa(void)
+static int test_aa(bool trylock)
{
struct ww_mutex mutex;
struct ww_acquire_ctx ctx;
int ret;
+ const char *from = trylock ? "trylock" : "lock";
ww_mutex_init(&mutex, &ww_class);
ww_acquire_init(&ctx, &ww_class);
- ww_mutex_lock(&mutex, &ctx);
+ if (!trylock) {
+ ret = ww_mutex_lock(&mutex, &ctx);
+ if (ret) {
+ pr_err("%s: initial lock failed!\n", __func__);
+ goto out;
+ }
+ } else {
+ if (!ww_mutex_trylock(&mutex, &ctx)) {
+ pr_err("%s: initial trylock failed!\n", __func__);
+ goto out;
+ }
+ }
- if (ww_mutex_trylock(&mutex)) {
- pr_err("%s: trylocked itself!\n", __func__);
+ if (ww_mutex_trylock(&mutex, NULL)) {
+ pr_err("%s: trylocked itself without context from %s!\n", __func__, from);
+ ww_mutex_unlock(&mutex);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (ww_mutex_trylock(&mutex, &ctx)) {
+ pr_err("%s: trylocked itself with context from %s!\n", __func__, from);
ww_mutex_unlock(&mutex);
ret = -EINVAL;
goto out;
@@ -129,17 +157,17 @@ static int test_aa(void)
ret = ww_mutex_lock(&mutex, &ctx);
if (ret != -EALREADY) {
- pr_err("%s: missed deadlock for recursing, ret=%d\n",
- __func__, ret);
+ pr_err("%s: missed deadlock for recursing, ret=%d from %s\n",
+ __func__, ret, from);
if (!ret)
ww_mutex_unlock(&mutex);
ret = -EINVAL;
goto out;
}
+ ww_mutex_unlock(&mutex);
ret = 0;
out:
- ww_mutex_unlock(&mutex);
ww_acquire_fini(&ctx);
return ret;
}
@@ -150,7 +178,7 @@ struct test_abba {
struct ww_mutex b_mutex;
struct completion a_ready;
struct completion b_ready;
- bool resolve;
+ bool resolve, trylock;
int result;
};
@@ -160,8 +188,13 @@ static void test_abba_work(struct work_struct *work)
struct ww_acquire_ctx ctx;
int err;
- ww_acquire_init(&ctx, &ww_class);
- ww_mutex_lock(&abba->b_mutex, &ctx);
+ ww_acquire_init_noinject(&ctx, &ww_class);
+ if (!abba->trylock)
+ ww_mutex_lock(&abba->b_mutex, &ctx);
+ else
+ WARN_ON(!ww_mutex_trylock(&abba->b_mutex, &ctx));
+
+ WARN_ON(READ_ONCE(abba->b_mutex.ctx) != &ctx);
complete(&abba->b_ready);
wait_for_completion(&abba->a_ready);
@@ -181,7 +214,7 @@ static void test_abba_work(struct work_struct *work)
abba->result = err;
}
-static int test_abba(bool resolve)
+static int test_abba(bool trylock, bool resolve)
{
struct test_abba abba;
struct ww_acquire_ctx ctx;
@@ -192,12 +225,18 @@ static int test_abba(bool resolve)
INIT_WORK_ONSTACK(&abba.work, test_abba_work);
init_completion(&abba.a_ready);
init_completion(&abba.b_ready);
+ abba.trylock = trylock;
abba.resolve = resolve;
schedule_work(&abba.work);
- ww_acquire_init(&ctx, &ww_class);
- ww_mutex_lock(&abba.a_mutex, &ctx);
+ ww_acquire_init_noinject(&ctx, &ww_class);
+ if (!trylock)
+ ww_mutex_lock(&abba.a_mutex, &ctx);
+ else
+ WARN_ON(!ww_mutex_trylock(&abba.a_mutex, &ctx));
+
+ WARN_ON(READ_ONCE(abba.a_mutex.ctx) != &ctx);
complete(&abba.a_ready);
wait_for_completion(&abba.b_ready);
@@ -249,7 +288,7 @@ static void test_cycle_work(struct work_struct *work)
struct ww_acquire_ctx ctx;
int err, erra = 0;
- ww_acquire_init(&ctx, &ww_class);
+ ww_acquire_init_noinject(&ctx, &ww_class);
ww_mutex_lock(&cycle->a_mutex, &ctx);
complete(cycle->a_signal);
@@ -581,7 +620,9 @@ static int stress(int nlocks, int nthreads, unsigned int flags)
static int __init test_ww_mutex_init(void)
{
int ncpus = num_online_cpus();
- int ret;
+ int ret, i;
+
+ printk(KERN_INFO "Beginning ww mutex selftests\n");
wq = alloc_workqueue("test-ww_mutex", WQ_UNBOUND, 0);
if (!wq)
@@ -591,17 +632,19 @@ static int __init test_ww_mutex_init(void)
if (ret)
return ret;
- ret = test_aa();
+ ret = test_aa(false);
if (ret)
return ret;
- ret = test_abba(false);
+ ret = test_aa(true);
if (ret)
return ret;
- ret = test_abba(true);
- if (ret)
- return ret;
+ for (i = 0; i < 4; i++) {
+ ret = test_abba(i & 1, i & 2);
+ if (ret)
+ return ret;
+ }
ret = test_cycle(ncpus);
if (ret)
@@ -619,6 +662,7 @@ static int __init test_ww_mutex_init(void)
if (ret)
return ret;
+ printk(KERN_INFO "All ww mutex selftests passed\n");
return 0;
}