@@ -26,6 +26,8 @@
*/
static unsigned int debug_locks_verbose;
+static DEFINE_WW_CLASS(ww_lockdep);
+
static int __init setup_debug_locks_verbose(char *str)
{
get_option(&str, &debug_locks_verbose);
@@ -42,6 +44,10 @@ __setup("debug_locks_verbose=", setup_debug_locks_verbose);
#define LOCKTYPE_RWLOCK 0x2
#define LOCKTYPE_MUTEX 0x4
#define LOCKTYPE_RWSEM 0x8
+#define LOCKTYPE_WW 0x10
+
+static struct ww_acquire_ctx t, t2;
+static struct ww_mutex o, o2;
/*
* Normal standalone locks, for the circular and irq-context
@@ -193,6 +199,20 @@ static void init_shared_classes(void)
#define RSU(x) up_read(&rwsem_##x)
#define RWSI(x) init_rwsem(&rwsem_##x)
+#ifndef CONFIG_DEBUG_WW_MUTEX_SLOWPATH
+#define WWAI(x) ww_acquire_init(x, &ww_lockdep)
+#else
+#define WWAI(x) do { ww_acquire_init(x, &ww_lockdep); (x)->deadlock_inject_countdown = ~0U; } while (0)
+#endif
+#define WWAD(x) ww_acquire_done(x)
+#define WWAF(x) ww_acquire_fini(x)
+
+#define WWL(x, c) ww_mutex_lock(x, c)
+#define WWT(x) ww_mutex_trylock(x)
+#define WWL1(x) ww_mutex_lock(x, NULL)
+#define WWU(x) ww_mutex_unlock(x)
+
+
#define LOCK_UNLOCK_2(x,y) LOCK(x); LOCK(y); UNLOCK(y); UNLOCK(x)
/*
@@ -894,11 +914,13 @@ GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_soft)
# define I_RWLOCK(x) lockdep_reset_lock(&rwlock_##x.dep_map)
# define I_MUTEX(x) lockdep_reset_lock(&mutex_##x.dep_map)
# define I_RWSEM(x) lockdep_reset_lock(&rwsem_##x.dep_map)
+# define I_WW(x) lockdep_reset_lock(&x.dep_map)
#else
# define I_SPINLOCK(x)
# define I_RWLOCK(x)
# define I_MUTEX(x)
# define I_RWSEM(x)
+# define I_WW(x)
#endif
#define I1(x) \
@@ -920,11 +942,20 @@ GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_soft)
static void reset_locks(void)
{
local_irq_disable();
+ lockdep_free_key_range(&ww_lockdep.acquire_key, 1);
+ lockdep_free_key_range(&ww_lockdep.mutex_key, 1);
+
I1(A); I1(B); I1(C); I1(D);
I1(X1); I1(X2); I1(Y1); I1(Y2); I1(Z1); I1(Z2);
+ I_WW(t); I_WW(t2); I_WW(o.base); I_WW(o2.base);
lockdep_reset();
I2(A); I2(B); I2(C); I2(D);
init_shared_classes();
+
+ ww_mutex_init(&o, &ww_lockdep); ww_mutex_init(&o2, &ww_lockdep);
+ memset(&t, 0, sizeof(t)); memset(&t2, 0, sizeof(t2));
+ memset(&ww_lockdep.acquire_key, 0, sizeof(ww_lockdep.acquire_key));
+ memset(&ww_lockdep.mutex_key, 0, sizeof(ww_lockdep.mutex_key));
local_irq_enable();
}
@@ -938,7 +969,6 @@ static int unexpected_testcase_failures;
static void dotest(void (*testcase_fn)(void), int expected, int lockclass_mask)
{
unsigned long saved_preempt_count = preempt_count();
- int expected_failure = 0;
WARN_ON(irqs_disabled());
@@ -946,26 +976,16 @@ static void dotest(void (*testcase_fn)(void), int expected, int lockclass_mask)
/*
* Filter out expected failures:
*/
+ if (debug_locks != expected) {
#ifndef CONFIG_PROVE_LOCKING
- if ((lockclass_mask & LOCKTYPE_SPIN) && debug_locks != expected)
- expected_failure = 1;
- if ((lockclass_mask & LOCKTYPE_RWLOCK) && debug_locks != expected)
- expected_failure = 1;
- if ((lockclass_mask & LOCKTYPE_MUTEX) && debug_locks != expected)
- expected_failure = 1;
- if ((lockclass_mask & LOCKTYPE_RWSEM) && debug_locks != expected)
- expected_failure = 1;
+ expected_testcase_failures++;
+ printk("failed|");
+#else
+ unexpected_testcase_failures++;
+ printk("FAILED|");
+
+ dump_stack();
#endif
- if (debug_locks != expected) {
- if (expected_failure) {
- expected_testcase_failures++;
- printk("failed|");
- } else {
- unexpected_testcase_failures++;
-
- printk("FAILED|");
- dump_stack();
- }
} else {
testcase_successes++;
printk(" ok |");
@@ -1108,6 +1128,346 @@ static inline void print_testname(const char *testname)
DO_TESTCASE_6IRW(desc, name, 312); \
DO_TESTCASE_6IRW(desc, name, 321);
+static void ww_test_fail_acquire(void)
+{
+ int ret;
+
+ WWAI(&t);
+ t.stamp++;
+
+ ret = WWL(&o, &t);
+
+ if (WARN_ON(!o.ctx) ||
+ WARN_ON(ret))
+ return;
+
+ /* No lockdep test, pure API */
+ ret = WWL(&o, &t);
+ WARN_ON(ret != -EALREADY);
+
+ ret = WWT(&o);
+ WARN_ON(ret);
+
+ t2 = t;
+ t2.stamp++;
+ ret = WWL(&o, &t2);
+ WARN_ON(ret != -EDEADLK);
+ WWU(&o);
+
+ if (WWT(&o))
+ WWU(&o);
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ else
+ DEBUG_LOCKS_WARN_ON(1);
+#endif
+}
+
+static void ww_test_two_contexts(void)
+{
+ WWAI(&t);
+ WWAI(&t2);
+}
+
+static void ww_test_diff_class(void)
+{
+ WWAI(&t);
+#ifdef CONFIG_DEBUG_MUTEXES
+ t.ww_class = NULL;
+#endif
+ WWL(&o, &t);
+}
+
+static void ww_test_context_done_twice(void)
+{
+ WWAI(&t);
+ WWAD(&t);
+ WWAD(&t);
+ WWAF(&t);
+}
+
+static void ww_test_context_unlock_twice(void)
+{
+ WWAI(&t);
+ WWAD(&t);
+ WWAF(&t);
+ WWAF(&t);
+}
+
+static void ww_test_context_fini_early(void)
+{
+ WWAI(&t);
+ WWL(&o, &t);
+ WWAD(&t);
+ WWAF(&t);
+}
+
+static void ww_test_context_lock_after_done(void)
+{
+ WWAI(&t);
+ WWAD(&t);
+ WWL(&o, &t);
+}
+
+static void ww_test_object_unlock_twice(void)
+{
+ WWL1(&o);
+ WWU(&o);
+ WWU(&o);
+}
+
+static void ww_test_object_lock_unbalanced(void)
+{
+ WWAI(&t);
+ WWL(&o, &t);
+ t.acquired = 0;
+ WWU(&o);
+ WWAF(&t);
+}
+
+static void ww_test_object_lock_stale_context(void)
+{
+ WWAI(&t);
+ o.ctx = &t2;
+ WWL(&o, &t);
+}
+
+static void ww_test_spin_nest_unlocked(void)
+{
+ raw_spin_lock_nest_lock(&lock_A, &o.base);
+ U(A);
+}
+
+static void ww_test_unneeded_slow(void)
+{
+ WWAI(&t);
+
+ ww_mutex_lock_slow(&o, &t);
+}
+
+static void ww_test_context_block(void)
+{
+ int ret;
+
+ WWAI(&t);
+
+ ret = WWL(&o, &t);
+ WARN_ON(ret);
+ WWL1(&o2);
+}
+
+static void ww_test_context_try(void)
+{
+ int ret;
+
+ WWAI(&t);
+
+ ret = WWL(&o, &t);
+ WARN_ON(ret);
+
+ ret = WWT(&o2);
+ WARN_ON(!ret);
+ WWU(&o2);
+ WWU(&o);
+}
+
+static void ww_test_context_context(void)
+{
+ int ret;
+
+ WWAI(&t);
+
+ ret = WWL(&o, &t);
+ WARN_ON(ret);
+
+ ret = WWL(&o2, &t);
+ WARN_ON(ret);
+
+ WWU(&o2);
+ WWU(&o);
+}
+
+static void ww_test_try_block(void)
+{
+ bool ret;
+
+ ret = WWT(&o);
+ WARN_ON(!ret);
+
+ WWL1(&o2);
+ WWU(&o2);
+ WWU(&o);
+}
+
+static void ww_test_try_try(void)
+{
+ bool ret;
+
+ ret = WWT(&o);
+ WARN_ON(!ret);
+ ret = WWT(&o2);
+ WARN_ON(!ret);
+ WWU(&o2);
+ WWU(&o);
+}
+
+static void ww_test_try_context(void)
+{
+ int ret;
+
+ ret = WWT(&o);
+ WARN_ON(!ret);
+
+ WWAI(&t);
+
+ ret = WWL(&o2, &t);
+ WARN_ON(ret);
+}
+
+static void ww_test_block_block(void)
+{
+ WWL1(&o);
+ WWL1(&o2);
+}
+
+static void ww_test_block_try(void)
+{
+ bool ret;
+
+ WWL1(&o);
+ ret = WWT(&o2);
+ WARN_ON(!ret);
+}
+
+static void ww_test_block_context(void)
+{
+ int ret;
+
+ WWL1(&o);
+ WWAI(&t);
+
+ ret = WWL(&o2, &t);
+ WARN_ON(ret);
+}
+
+static void ww_test_spin_block(void)
+{
+ L(A);
+ U(A);
+
+ WWL1(&o);
+ L(A);
+ U(A);
+ WWU(&o);
+
+ L(A);
+ WWL1(&o);
+ WWU(&o);
+ U(A);
+}
+
+static void ww_test_spin_try(void)
+{
+ bool ret;
+
+ L(A);
+ U(A);
+
+ ret = WWT(&o);
+ WARN_ON(!ret);
+ L(A);
+ U(A);
+ WWU(&o);
+
+ L(A);
+ ret = WWT(&o);
+ WARN_ON(!ret);
+ WWU(&o);
+ U(A);
+}
+
+static void ww_test_spin_context(void)
+{
+ int ret;
+
+ L(A);
+ U(A);
+
+ WWAI(&t);
+
+ ret = WWL(&o, &t);
+ WARN_ON(ret);
+ L(A);
+ U(A);
+ WWU(&o);
+
+ L(A);
+ ret = WWL(&o, &t);
+ WARN_ON(ret);
+ WWU(&o);
+ U(A);
+}
+
+static void ww_tests(void)
+{
+ printk(" --------------------------------------------------------------------------\n");
+ printk(" | Wound/wait tests |\n");
+ printk(" ---------------------\n");
+
+ print_testname("ww api failures");
+ dotest(ww_test_fail_acquire, SUCCESS, LOCKTYPE_WW);
+ dotest(ww_test_unneeded_slow, FAILURE, LOCKTYPE_WW);
+ printk("\n");
+
+ print_testname("ww contexts mixing");
+ dotest(ww_test_two_contexts, FAILURE, LOCKTYPE_WW);
+ dotest(ww_test_diff_class, FAILURE, LOCKTYPE_WW);
+ printk("\n");
+
+ print_testname("finishing ww context");
+ dotest(ww_test_context_done_twice, FAILURE, LOCKTYPE_WW);
+ dotest(ww_test_context_unlock_twice, FAILURE, LOCKTYPE_WW);
+ dotest(ww_test_context_fini_early, FAILURE, LOCKTYPE_WW);
+ dotest(ww_test_context_lock_after_done, FAILURE, LOCKTYPE_WW);
+ printk("\n");
+
+ print_testname("locking mismatches");
+ dotest(ww_test_object_unlock_twice, FAILURE, LOCKTYPE_WW);
+ dotest(ww_test_object_lock_unbalanced, FAILURE, LOCKTYPE_WW);
+ dotest(ww_test_object_lock_stale_context, FAILURE, LOCKTYPE_WW);
+ printk("\n");
+
+ print_testname("spinlock nest unlocked");
+ dotest(ww_test_spin_nest_unlocked, FAILURE, LOCKTYPE_WW);
+ printk("\n");
+
+ printk(" -----------------------------------------------------\n");
+ printk(" |block | try |context|\n");
+ printk(" -----------------------------------------------------\n");
+
+ print_testname("context");
+ dotest(ww_test_context_block, FAILURE, LOCKTYPE_WW);
+ dotest(ww_test_context_try, SUCCESS, LOCKTYPE_WW);
+ dotest(ww_test_context_context, SUCCESS, LOCKTYPE_WW);
+ printk("\n");
+
+ print_testname("try");
+ dotest(ww_test_try_block, FAILURE, LOCKTYPE_WW);
+ dotest(ww_test_try_try, SUCCESS, LOCKTYPE_WW);
+ dotest(ww_test_try_context, FAILURE, LOCKTYPE_WW);
+ printk("\n");
+
+ print_testname("block");
+ dotest(ww_test_block_block, FAILURE, LOCKTYPE_WW);
+ dotest(ww_test_block_try, SUCCESS, LOCKTYPE_WW);
+ dotest(ww_test_block_context, FAILURE, LOCKTYPE_WW);
+ printk("\n");
+
+ print_testname("spinlock");
+ dotest(ww_test_spin_block, FAILURE, LOCKTYPE_WW);
+ dotest(ww_test_spin_try, SUCCESS, LOCKTYPE_WW);
+ dotest(ww_test_spin_context, FAILURE, LOCKTYPE_WW);
+ printk("\n");
+}
void locking_selftest(void)
{
@@ -1188,6 +1548,8 @@ void locking_selftest(void)
DO_TESTCASE_6x2("irq read-recursion", irq_read_recursion);
// DO_TESTCASE_6x2B("irq read-recursion #2", irq_read_recursion2);
+ ww_tests();
+
if (unexpected_testcase_failures) {
printk("-----------------------------------------------------------------\n");
debug_locks = 0;
This stresses the lockdep code in some ways specifically useful to ww_mutexes. It adds checks for most of the common locking errors. Changes since v1: - Add tests to verify reservation_id is untouched. - Use L() and U() macros where possible. Changes since v2: - Use the ww_mutex api directly. - Use macros for most of the code. Changes since v3: - Rework tests for the api changes. Changes since v4: - Added a test to cover ww_acquire_done being called multiple times. - Added a test for calling ww_acquire_fini being called before all locks have been unlocked. - Added a test for locking after ww_acquire_done has been called. - Added a test for unbalance for ctx->acquired dropping below zero. - Added a test for unlocked ww_mutex with ctx != NULL. Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com> --- lib/locking-selftest.c | 400 ++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 381 insertions(+), 19 deletions(-)