locking-selftest.c

Lib files of linux kernel

#include "locking-selftest-spin.h"
GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_spin)

#include "locking-selftest-wlock.h"
GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_wlock)

#include "locking-selftest-rlock.h"
GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_rlock)

#undef E1
#undef E2

/*
 * Enabling irqs with an irq-safe lock held:
 */
#define E1()				\
					\
	IRQ_ENTER();			\
	LOCK(A);			\
	UNLOCK(A);			\
	IRQ_EXIT();

#define E2()				\
					\
	IRQ_DISABLE();			\
	LOCK(A);			\
	IRQ_ENABLE();			\
	UNLOCK(A);

/*
 * Generate 24 testcases:
 */
#include "locking-selftest-spin-hardirq.h"
GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_spin)

#include "locking-selftest-rlock-hardirq.h"
GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_rlock)

#include "locking-selftest-wlock-hardirq.h"
GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_wlock)

#include "locking-selftest-spin-softirq.h"
GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_spin)

#include "locking-selftest-rlock-softirq.h"
GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_rlock)

#include "locking-selftest-wlock-softirq.h"
GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_wlock)

#undef E1
#undef E2

/*
 * Acquiring a irq-unsafe lock while holding an irq-safe-lock:
 */
#define E1()				\
					\
	LOCK(A);			\
	LOCK(B);			\
	UNLOCK(B);			\
	UNLOCK(A);			\

#define E2()				\
					\
	LOCK(B);			\
	UNLOCK(B);

#define E3()				\
					\
	IRQ_ENTER();			\
	LOCK(A);			\
	UNLOCK(A);			\
	IRQ_EXIT();

/*
 * Generate 36 testcases:
 */
#include "locking-selftest-spin-hardirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_spin)

#include "locking-selftest-rlock-hardirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_rlock)

#include "locking-selftest-wlock-hardirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_wlock)

#include "locking-selftest-spin-softirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_spin)

#include "locking-selftest-rlock-softirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_rlock)

#include "locking-selftest-wlock-softirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_wlock)

#undef E1
#undef E2
#undef E3

/*
 * If a lock turns into softirq-safe, but earlier it took
 * a softirq-unsafe lock:
 */

#define E1()				\
	IRQ_DISABLE();			\
	LOCK(A);			\
	LOCK(B);			\
	UNLOCK(B);			\
	UNLOCK(A);			\
	IRQ_ENABLE();

#define E2()				\
	LOCK(B);			\
	UNLOCK(B);

#define E3()				\
	IRQ_ENTER();			\
	LOCK(A);			\
	UNLOCK(A);			\
	IRQ_EXIT();

/*
 * Generate 36 testcases:
 */
#include "locking-selftest-spin-hardirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_spin)

#include "locking-selftest-rlock-hardirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_rlock)

#include "locking-selftest-wlock-hardirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_wlock)

#include "locking-selftest-spin-softirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_spin)

#include "locking-selftest-rlock-softirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_rlock)

#include "locking-selftest-wlock-softirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_wlock)

#undef E1
#undef E2
#undef E3

/*
 * read-lock / write-lock irq inversion.
 *
 * Deadlock scenario:
 *
 * CPU#1 is at #1, i.e. it has write-locked A, but has not
 * taken B yet.
 *
 * CPU#2 is at #2, i.e. it has locked B.
 *
 * Hardirq hits CPU#2 at point #2 and is trying to read-lock A.
 *
 * The deadlock occurs because CPU#1 will spin on B, and CPU#2
 * will spin on A.
 */

#define E1()				\
					\
	IRQ_DISABLE();			\
	WL(A);				\
	LOCK(B);			\
	UNLOCK(B);			\
	WU(A);				\
	IRQ_ENABLE();

#define E2()				\
					\
	LOCK(B);			\
	UNLOCK(B);

#define E3()				\
					\
	IRQ_ENTER();			\
	RL(A);				\
	RU(A);				\
	IRQ_EXIT();

/*
 * Generate 36 testcases:
 */
#include "locking-selftest-spin-hardirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_hard_spin)

#include "locking-selftest-rlock-hardirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_hard_rlock)

#include "locking-selftest-wlock-hardirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_hard_wlock)

#include "locking-selftest-spin-softirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_soft_spin)

#include "locking-selftest-rlock-softirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_soft_rlock)

#include "locking-selftest-wlock-softirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_soft_wlock)

#undef E1
#undef E2
#undef E3

/*
 * read-lock / write-lock recursion that is actually safe.
 */

#define E1()				\
					\
	IRQ_DISABLE();			\
	WL(A);				\
	WU(A);				\
	IRQ_ENABLE();

#define E2()				\
					\
	RL(A);				\
	RU(A);				\

#define E3()				\
					\
	IRQ_ENTER();			\
	RL(A);				\
	L(B);				\
	U(B);				\
	RU(A);				\
	IRQ_EXIT();

/*
 * Generate 12 testcases:
 */
#include "locking-selftest-hardirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_hard)

#include "locking-selftest-softirq.h"
GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_soft)

#undef E1
#undef E2
#undef E3

/*
 * read-lock / write-lock recursion that is unsafe.
 */

#define E1()				\
					\
	IRQ_DISABLE();			\
	L(B);				\
	WL(A);				\
	WU(A);				\
	U(B);				\
	IRQ_ENABLE();

#define E2()				\
					\
	RL(A);				\
	RU(A);				\

#define E3()				\
					\
	IRQ_ENTER();			\
	L(B);				\
	U(B);				\
	IRQ_EXIT();

/*
 * Generate 12 testcases:
 */
#include "locking-selftest-hardirq.h"
// GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion2_hard)

#include "locking-selftest-softirq.h"
// GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion2_soft)

#ifdef CONFIG_DEBUG_LOCK_ALLOC
# define I_SPINLOCK(x)	lockdep_reset_lock(&lock_##x.dep_map)
# 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)
#else
# define I_SPINLOCK(x)
# define I_RWLOCK(x)
# define I_MUTEX(x)
# define I_RWSEM(x)
#endif

#define I1(x)					\
	do {					\
		I_SPINLOCK(x);			\
		I_RWLOCK(x);			\
		I_MUTEX(x);			\
		I_RWSEM(x);			\
	} while (0)

#define I2(x)					\
	do {					\
		spin_lock_init(&lock_##x);	\
		rwlock_init(&rwlock_##x);	\
		mutex_init(&mutex_##x);		\
		init_rwsem(&rwsem_##x);		\
	} while (0)

static void reset_locks(void)
{
	local_irq_disable();
	I1(A); I1(B); I1(C); I1(D);
	I1(X1); I1(X2); I1(Y1); I1(Y2); I1(Z1); I1(Z2);
	lockdep_reset();
	I2(A); I2(B); I2(C); I2(D);
	init_shared_classes();
	local_irq_enable();
}

#undef I

static int testcase_total;
static int testcase_successes;
static int expected_testcase_failures;
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());

	testcase_fn();
	/*
	 * Filter out expected failures:
	 */
#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;
#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  |");
	}
	testcase_total++;

	if (debug_locks_verbose)
		printk(" lockclass mask: %x, debug_locks: %d, expected: %d\n",
			lockclass_mask, debug_locks, expected);
	/*
	 * Some tests (e.g. double-unlock) might corrupt the preemption
	 * count, so restore it:
	 */
	preempt_count() = saved_preempt_count;
#ifdef CONFIG_TRACE_IRQFLAGS
	if (softirq_count())
		current->softirqs_enabled = 0;
	else
		current->softirqs_enabled = 1;
#endif

	reset_locks();
}

static inline void print_testname(const char *testname)
{
	printk("%33s:", testname);
}

#define DO_TESTCASE_1(desc, name, nr)				\
	print_testname(desc"/"#nr);				\
	dotest(name##_##nr, SUCCESS, LOCKTYPE_RWLOCK);		\
	printk("\n");

#define DO_TESTCASE_1B(desc, name, nr)				\
	print_testname(desc"/"#nr);				\
	dotest(name##_##nr, FAILURE, LOCKTYPE_RWLOCK);		\
	printk("\n");

#define DO_TESTCASE_3(desc, name, nr)				\
	print_testname(desc"/"#nr);				\
	dotest(name##_spin_##nr, FAILURE, LOCKTYPE_SPIN);	\
	dotest(name##_wlock_##nr, FAILURE, LOCKTYPE_RWLOCK);	\
	dotest(name##_rlock_##nr, SUCCESS, LOCKTYPE_RWLOCK);	\
	printk("\n");

#define DO_TESTCASE_3RW(desc, name, nr)				\
	print_testname(desc"/"#nr);				\
	dotest(name##_spin_##nr, FAILURE, LOCKTYPE_SPIN|LOCKTYPE_RWLOCK);\
	dotest(name##_wlock_##nr, FAILURE, LOCKTYPE_RWLOCK);	\
	dotest(name##_rlock_##nr, SUCCESS, LOCKTYPE_RWLOCK);	\
	printk("\n");

#define DO_TESTCASE_6(desc, name)				\
	print_testname(desc);					\
	dotest(name##_spin, FAILURE, LOCKTYPE_SPIN);		\
	dotest(name##_wlock, FAILURE, LOCKTYPE_RWLOCK);		\
	dotest(name##_rlock, FAILURE, LOCKTYPE_RWLOCK);		\
	dotest(name##_mutex, FAILURE, LOCKTYPE_MUTEX);		\
	dotest(name##_wsem, FAILURE, LOCKTYPE_RWSEM);		\
	dotest(name##_rsem, FAILURE, LOCKTYPE_RWSEM);		\
	printk("\n");

#define DO_TESTCASE_6_SUCCESS(desc, name)			\
	print_testname(desc);					\
	dotest(name##_spin, SUCCESS, LOCKTYPE_SPIN);		\
	dotest(name##_wlock, SUCCESS, LOCKTYPE_RWLOCK);		\
	dotest(name##_rlock, SUCCESS, LOCKTYPE_RWLOCK);		\
	dotest(name##_mutex, SUCCESS, LOCKTYPE_MUTEX);		\
	dotest(name##_wsem, SUCCESS, LOCKTYPE_RWSEM);		\
	dotest(name##_rsem, SUCCESS, LOCKTYPE_RWSEM);		\
	printk("\n");

/*
 * 'read' variant: rlocks must not trigger.
 */
#define DO_TESTCASE_6R(desc, name)				\
	print_testname(desc);					\
	dotest(name##_spin, FAILURE, LOCKTYPE_SPIN);		\
	dotest(name##_wlock, FAILURE, LOCKTYPE_RWLOCK);		\
	dotest(name##_rlock, SUCCESS, LOCKTYPE_RWLOCK);		\
	dotest(name##_mutex, FAILURE, LOCKTYPE_MUTEX);		\
	dotest(name##_wsem, FAILURE, LOCKTYPE_RWSEM);		\
	dotest(name##_rsem, FAILURE, LOCKTYPE_RWSEM);		\
	printk("\n");

#define DO_TESTCASE_2I(desc, name, nr)				\
	DO_TESTCASE_1("hard-"desc, name##_hard, nr);		\
	DO_TESTCASE_1("soft-"desc, name##_soft, nr);

#define DO_TESTCASE_2IB(desc, name, nr)				\
	DO_TESTCASE_1B("hard-"desc, name##_hard, nr);		\
	DO_TESTCASE_1B("soft-"desc, name##_soft, nr);

#define DO_TESTCASE_6I(desc, name, nr)				\
	DO_TESTCASE_3("hard-"desc, name##_hard, nr);		\
	DO_TESTCASE_3("soft-"desc, name##_soft, nr);

#define DO_TESTCASE_6IRW(desc, name, nr)			\
	DO_TESTCASE_3RW("hard-"desc, name##_hard, nr);		\
	DO_TESTCASE_3RW("soft-"desc, name##_soft, nr);

#define DO_TESTCASE_2x3(desc, name)				\
	DO_TESTCASE_3(desc, name, 12);				\
	DO_TESTCASE_3(desc, name, 21);

#define DO_TESTCASE_2x6(desc, name)				\
	DO_TESTCASE_6I(desc, name, 12);				\
	DO_TESTCASE_6I(desc, name, 21);

#define DO_TESTCASE_6x2(desc, name)				\
	DO_TESTCASE_2I(desc, name, 123);			\
	DO_TESTCASE_2I(desc, name, 132);			\
	DO_TESTCASE_2I(desc, name, 213);			\
	DO_TESTCASE_2I(desc, name, 231);			\
	DO_TESTCASE_2I(desc, name, 312);			\
	DO_TESTCASE_2I(desc, name, 321);

#define DO_TESTCASE_6x2B(desc, name)				\
	DO_TESTCASE_2IB(desc, name, 123);			\
	DO_TESTCASE_2IB(desc, name, 132);			\
	DO_TESTCASE_2IB(desc, name, 213);			\
	DO_TESTCASE_2IB(desc, name, 231);			\
	DO_TESTCASE_2IB(desc, name, 312);			\
	DO_TESTCASE_2IB(desc, name, 321);

#define DO_TESTCASE_6x6(desc, name)				\
	DO_TESTCASE_6I(desc, name, 123);			\
	DO_TESTCASE_6I(desc, name, 132);			\
	DO_TESTCASE_6I(desc, name, 213);			\
	DO_TESTCASE_6I(desc, name, 231);			\
	DO_TESTCASE_6I(desc, name, 312);			\
	DO_TESTCASE_6I(desc, name, 321);

#define DO_TESTCASE_6x6RW(desc, name)				\
	DO_TESTCASE_6IRW(desc, name, 123);			\
	DO_TESTCASE_6IRW(desc, name, 132);			\
	DO_TESTCASE_6IRW(desc, name, 213);			\
	DO_TESTCASE_6IRW(desc, name, 231);			\
	DO_TESTCASE_6IRW(desc, name, 312);			\
	DO_TESTCASE_6IRW(desc, name, 321);


void locking_selftest(void)
{
	/*
	 * Got a locking failure before the selftest ran?
	 */
	if (!debug_locks) {
		printk("----------------------------------\n");
		printk("| Locking API testsuite disabled |\n");
		printk("----------------------------------\n");
		return;
	}

	/*
	 * Run the testsuite:
	 */
	printk("------------------------\n");
	printk("| Locking API testsuite:\n");
	printk("----------------------------------------------------------------------------\n");
	printk("                                 | spin |wlock |rlock |mutex | wsem | rsem |\n");
	printk("  --------------------------------------------------------------------------\n");

	init_shared_classes();
	debug_locks_silent = !debug_locks_verbose;

	DO_TESTCASE_6R("A-A deadlock", AA);
	DO_TESTCASE_6R("A-B-B-A deadlock", ABBA);
	DO_TESTCASE_6R("A-B-B-C-C-A deadlock", ABBCCA);
	DO_TESTCASE_6R("A-B-C-A-B-C deadlock", ABCABC);
	DO_TESTCASE_6R("A-B-B-C-C-D-D-A deadlock", ABBCCDDA);
	DO_TESTCASE_6R("A-B-C-D-B-D-D-A deadlock", ABCDBDDA);
	DO_TESTCASE_6R("A-B-C-D-B-C-D-A deadlock", ABCDBCDA);
	DO_TESTCASE_6("double unlock", double_unlock);
	DO_TESTCASE_6("initialize held", init_held);
	DO_TESTCASE_6_SUCCESS("bad unlock order", bad_unlock_order);

	printk("  --------------------------------------------------------------------------\n");
	print_testname("recursive read-lock");
	printk("             |");
	dotest(rlock_AA1, SUCCESS, LOCKTYPE_RWLOCK);
	printk("             |");
	dotest(rsem_AA1, FAILURE, LOCKTYPE_RWSEM);
	printk("\n");

	print_testname("recursive read-lock #2");
	printk("             |");
	dotest(rlock_AA1B, SUCCESS, LOCKTYPE_RWLOCK);
	printk("             |");
	dotest(rsem_AA1B, FAILURE, LOCKTYPE_RWSEM);
	printk("\n");

	print_testname("mixed read-write-lock");
	printk("             |");
	dotest(rlock_AA2, FAILURE, LOCKTYPE_RWLOCK);
	printk("             |");
	dotest(rsem_AA2, FAILURE, LOCKTYPE_RWSEM);
	printk("\n");

	print_testname("mixed write-read-lock");
	printk("             |");
	dotest(rlock_AA3, FAILURE, LOCKTYPE_RWLOCK);
	printk("             |");
	dotest(rsem_AA3, FAILURE, LOCKTYPE_RWSEM);
	printk("\n");

	printk("  --------------------------------------------------------------------------\n");

	/*
	 * irq-context testcases:
	 */
	DO_TESTCASE_2x6("irqs-on + irq-safe-A", irqsafe1);
	DO_TESTCASE_2x3("sirq-safe-A => hirqs-on", irqsafe2A);
	DO_TESTCASE_2x6("safe-A + irqs-on", irqsafe2B);
	DO_TESTCASE_6x6("safe-A + unsafe-B #1", irqsafe3);
	DO_TESTCASE_6x6("safe-A + unsafe-B #2", irqsafe4);
	DO_TESTCASE_6x6RW("irq lock-inversion", irq_inversion);

	DO_TESTCASE_6x2("irq read-recursion", irq_read_recursion);
//	DO_TESTCASE_6x2B("irq read-recursion #2", irq_read_recursion2);

	if (unexpected_testcase_failures) {
		printk("-----------------------------------------------------------------\n");
		debug_locks = 0;
		printk("BUG: %3d unexpected failures (out of %3d) - debugging disabled! |\n",
			unexpected_testcase_failures, testcase_total);
		printk("-----------------------------------------------------------------\n");
	} else if (expected_testcase_failures && testcase_successes) {
		printk("--------------------------------------------------------\n");
		printk("%3d out of %3d testcases failed, as expected. |\n",
			expected_testcase_failures, testcase_total);
		printk("----------------------------------------------------\n");
		debug_locks = 1;
	} else if (expected_testcase_failures && !testcase_successes) {
		printk("--------------------------------------------------------\n");
		printk("All %3d testcases failed, as expected. |\n",
			expected_testcase_failures);
		printk("----------------------------------------\n");
		debug_locks = 1;
	} else {
		printk("-------------------------------------------------------\n");
		printk("Good, all %3d testcases passed! |\n",
			testcase_successes);
		printk("---------------------------------\n");
		debug_locks = 1;
	}
	debug_locks_silent = 0;
}