[GitHub/mt8127/android_kernel_alcatel_ttab.git] / lib / spinlock_debug.c

/*
 * Copyright 2005, Red Hat, Inc., Ingo Molnar
 * Released under the General Public License (GPL).
 *
 * This file contains the spinlock/rwlock implementations for
 * DEBUG_SPINLOCK.
 */

#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/debug_locks.h>
#include <linux/delay.h>
#include <linux/module.h>

void __spin_lock_init(spinlock_t *lock, const char *name,
		      struct lock_class_key *key)
{
#ifdef CONFIG_DEBUG_LOCK_ALLOC
	/*
	 * Make sure we are not reinitializing a held lock:
	 */
	debug_check_no_locks_freed((void *)lock, sizeof(*lock));
	lockdep_init_map(&lock->dep_map, name, key, 0);
#endif
	lock->raw_lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
	lock->magic = SPINLOCK_MAGIC;
	lock->owner = SPINLOCK_OWNER_INIT;
	lock->owner_cpu = -1;
}

EXPORT_SYMBOL(__spin_lock_init);

void __rwlock_init(rwlock_t *lock, const char *name,
		   struct lock_class_key *key)
{
#ifdef CONFIG_DEBUG_LOCK_ALLOC
	/*
	 * Make sure we are not reinitializing a held lock:
	 */
	debug_check_no_locks_freed((void *)lock, sizeof(*lock));
	lockdep_init_map(&lock->dep_map, name, key, 0);
#endif
	lock->raw_lock = (raw_rwlock_t) __RAW_RW_LOCK_UNLOCKED;
	lock->magic = RWLOCK_MAGIC;
	lock->owner = SPINLOCK_OWNER_INIT;
	lock->owner_cpu = -1;
}

EXPORT_SYMBOL(__rwlock_init);

static void spin_bug(spinlock_t *lock, const char *msg)
{
	struct task_struct *owner = NULL;

	if (!debug_locks_off())
		return;

	if (lock->owner && lock->owner != SPINLOCK_OWNER_INIT)
		owner = lock->owner;
	printk(KERN_EMERG "BUG: spinlock %s on CPU#%d, %s/%d\n",
		msg, raw_smp_processor_id(),
		current->comm, current->pid);
	printk(KERN_EMERG " lock: %p, .magic: %08x, .owner: %s/%d, "
			".owner_cpu: %d\n",
		lock, lock->magic,
		owner ? owner->comm : "<none>",
		owner ? owner->pid : -1,
		lock->owner_cpu);
	dump_stack();
}

#define SPIN_BUG_ON(cond, lock, msg) if (unlikely(cond)) spin_bug(lock, msg)

static inline void
debug_spin_lock_before(spinlock_t *lock)
{
	SPIN_BUG_ON(lock->magic != SPINLOCK_MAGIC, lock, "bad magic");
	SPIN_BUG_ON(lock->owner == current, lock, "recursion");
	SPIN_BUG_ON(lock->owner_cpu == raw_smp_processor_id(),
							lock, "cpu recursion");
}

static inline void debug_spin_lock_after(spinlock_t *lock)
{
	lock->owner_cpu = raw_smp_processor_id();
	lock->owner = current;
}

static inline void debug_spin_unlock(spinlock_t *lock)
{
	SPIN_BUG_ON(lock->magic != SPINLOCK_MAGIC, lock, "bad magic");
	SPIN_BUG_ON(!spin_is_locked(lock), lock, "already unlocked");
	SPIN_BUG_ON(lock->owner != current, lock, "wrong owner");
	SPIN_BUG_ON(lock->owner_cpu != raw_smp_processor_id(),
							lock, "wrong CPU");
	lock->owner = SPINLOCK_OWNER_INIT;
	lock->owner_cpu = -1;
}

static void __spin_lock_debug(spinlock_t *lock)
{
	u64 i;
	u64 loops = loops_per_jiffy * HZ;
	int print_once = 1;

	for (;;) {
		for (i = 0; i < loops; i++) {
			if (__raw_spin_trylock(&lock->raw_lock))
				return;
			__delay(1);
		}
		/* lockup suspected: */
		if (print_once) {
			print_once = 0;
			printk(KERN_EMERG "BUG: spinlock lockup on CPU#%d, "
					"%s/%d, %p\n",
				raw_smp_processor_id(), current->comm,
				current->pid, lock);
			dump_stack();
		}
	}
}

void _raw_spin_lock(spinlock_t *lock)
{
	debug_spin_lock_before(lock);
	if (unlikely(!__raw_spin_trylock(&lock->raw_lock)))
		__spin_lock_debug(lock);
	debug_spin_lock_after(lock);
}

int _raw_spin_trylock(spinlock_t *lock)
{
	int ret = __raw_spin_trylock(&lock->raw_lock);

	if (ret)
		debug_spin_lock_after(lock);
#ifndef CONFIG_SMP
	/*
	 * Must not happen on UP:
	 */
	SPIN_BUG_ON(!ret, lock, "trylock failure on UP");
#endif
	return ret;
}

void _raw_spin_unlock(spinlock_t *lock)
{
	debug_spin_unlock(lock);
	__raw_spin_unlock(&lock->raw_lock);
}

static void rwlock_bug(rwlock_t *lock, const char *msg)
{
	if (!debug_locks_off())
		return;

	printk(KERN_EMERG "BUG: rwlock %s on CPU#%d, %s/%d, %p\n",
		msg, raw_smp_processor_id(), current->comm,
		current->pid, lock);
	dump_stack();
}

#define RWLOCK_BUG_ON(cond, lock, msg) if (unlikely(cond)) rwlock_bug(lock, msg)

#if 0		/* __write_lock_debug() can lock up - maybe this can too? */
static void __read_lock_debug(rwlock_t *lock)
{
	u64 i;
	u64 loops = loops_per_jiffy * HZ;
	int print_once = 1;

	for (;;) {
		for (i = 0; i < loops; i++) {
			if (__raw_read_trylock(&lock->raw_lock))
				return;
			__delay(1);
		}
		/* lockup suspected: */
		if (print_once) {
			print_once = 0;
			printk(KERN_EMERG "BUG: read-lock lockup on CPU#%d, "
					"%s/%d, %p\n",
				raw_smp_processor_id(), current->comm,
				current->pid, lock);
			dump_stack();
		}
	}
}
#endif

void _raw_read_lock(rwlock_t *lock)
{
	RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
	__raw_read_lock(&lock->raw_lock);
}

int _raw_read_trylock(rwlock_t *lock)
{
	int ret = __raw_read_trylock(&lock->raw_lock);

#ifndef CONFIG_SMP
	/*
	 * Must not happen on UP:
	 */
	RWLOCK_BUG_ON(!ret, lock, "trylock failure on UP");
#endif
	return ret;
}

void _raw_read_unlock(rwlock_t *lock)
{
	RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
	__raw_read_unlock(&lock->raw_lock);
}

static inline void debug_write_lock_before(rwlock_t *lock)
{
	RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
	RWLOCK_BUG_ON(lock->owner == current, lock, "recursion");
	RWLOCK_BUG_ON(lock->owner_cpu == raw_smp_processor_id(),
							lock, "cpu recursion");
}

static inline void debug_write_lock_after(rwlock_t *lock)
{
	lock->owner_cpu = raw_smp_processor_id();
	lock->owner = current;
}

static inline void debug_write_unlock(rwlock_t *lock)
{
	RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
	RWLOCK_BUG_ON(lock->owner != current, lock, "wrong owner");
	RWLOCK_BUG_ON(lock->owner_cpu != raw_smp_processor_id(),
							lock, "wrong CPU");
	lock->owner = SPINLOCK_OWNER_INIT;
	lock->owner_cpu = -1;
}

#if 0		/* This can cause lockups */
static void __write_lock_debug(rwlock_t *lock)
{
	u64 i;
	u64 loops = loops_per_jiffy * HZ;
	int print_once = 1;

	for (;;) {
		for (i = 0; i < loops; i++) {
			if (__raw_write_trylock(&lock->raw_lock))
				return;
			__delay(1);
		}
		/* lockup suspected: */
		if (print_once) {
			print_once = 0;
			printk(KERN_EMERG "BUG: write-lock lockup on CPU#%d, "
					"%s/%d, %p\n",
				raw_smp_processor_id(), current->comm,
				current->pid, lock);
			dump_stack();
		}
	}
}
#endif

void _raw_write_lock(rwlock_t *lock)
{
	debug_write_lock_before(lock);
	__raw_write_lock(&lock->raw_lock);
	debug_write_lock_after(lock);
}

int _raw_write_trylock(rwlock_t *lock)
{
	int ret = __raw_write_trylock(&lock->raw_lock);

	if (ret)
		debug_write_lock_after(lock);
#ifndef CONFIG_SMP
	/*
	 * Must not happen on UP:
	 */
	RWLOCK_BUG_ON(!ret, lock, "trylock failure on UP");
#endif
	return ret;
}

void _raw_write_unlock(rwlock_t *lock)
{
	debug_write_unlock(lock);
	__raw_write_unlock(&lock->raw_lock);
}
Commit	Line	Data
fb1c8f93 IM	1	/*
	2	* Copyright 2005, Red Hat, Inc., Ingo Molnar
	3	* Released under the General Public License (GPL).
	4	*
	5	* This file contains the spinlock/rwlock implementations for
	6	* DEBUG_SPINLOCK.
	7	*/
	8
fb1c8f93 IM	9	#include <linux/spinlock.h>
fb1c8f93 IM	10	#include <linux/interrupt.h>
9a11b49a	11	#include <linux/debug_locks.h>
fb1c8f93	12	#include <linux/delay.h>
9a11b49a	13	#include <linux/module.h>
fb1c8f93	14
8a25d5de IM	15	void __spin_lock_init(spinlock_t lock, const char name,
	16	struct lock_class_key *key)
	17	{
	18	#ifdef CONFIG_DEBUG_LOCK_ALLOC
	19	/*
	20	* Make sure we are not reinitializing a held lock:
	21	*/
	22	debug_check_no_locks_freed((void )lock, sizeof(lock));
4dfbb9d8	23	lockdep_init_map(&lock->dep_map, name, key, 0);
8a25d5de IM	24	#endif
	25	lock->raw_lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
	26	lock->magic = SPINLOCK_MAGIC;
	27	lock->owner = SPINLOCK_OWNER_INIT;
	28	lock->owner_cpu = -1;
	29	}
	30
	31	EXPORT_SYMBOL(__spin_lock_init);
	32
	33	void __rwlock_init(rwlock_t lock, const char name,
	34	struct lock_class_key *key)
	35	{
	36	#ifdef CONFIG_DEBUG_LOCK_ALLOC
	37	/*
	38	* Make sure we are not reinitializing a held lock:
	39	*/
	40	debug_check_no_locks_freed((void )lock, sizeof(lock));
4dfbb9d8	41	lockdep_init_map(&lock->dep_map, name, key, 0);
8a25d5de IM	42	#endif
	43	lock->raw_lock = (raw_rwlock_t) __RAW_RW_LOCK_UNLOCKED;
	44	lock->magic = RWLOCK_MAGIC;
	45	lock->owner = SPINLOCK_OWNER_INIT;
	46	lock->owner_cpu = -1;
	47	}
	48
	49	EXPORT_SYMBOL(__rwlock_init);
	50
fb1c8f93 IM	51	static void spin_bug(spinlock_t lock, const char msg)
fb1c8f93 IM	52	{
fb1c8f93 IM	53	struct task_struct *owner = NULL;
fb1c8f93 IM	54
9a11b49a IM	55	if (!debug_locks_off())
	56	return;
	57
	58	if (lock->owner && lock->owner != SPINLOCK_OWNER_INIT)
	59	owner = lock->owner;
	60	printk(KERN_EMERG "BUG: spinlock %s on CPU#%d, %s/%d\n",
	61	msg, raw_smp_processor_id(),
	62	current->comm, current->pid);
	63	printk(KERN_EMERG " lock: %p, .magic: %08x, .owner: %s/%d, "
	64	".owner_cpu: %d\n",
	65	lock, lock->magic,
	66	owner ? owner->comm : "<none>",
	67	owner ? owner->pid : -1,
	68	lock->owner_cpu);
	69	dump_stack();
fb1c8f93 IM	70	}
	71
	72	#define SPIN_BUG_ON(cond, lock, msg) if (unlikely(cond)) spin_bug(lock, msg)
	73
9a11b49a IM	74	static inline void
9a11b49a IM	75	debug_spin_lock_before(spinlock_t *lock)
fb1c8f93 IM	76	{
	77	SPIN_BUG_ON(lock->magic != SPINLOCK_MAGIC, lock, "bad magic");
	78	SPIN_BUG_ON(lock->owner == current, lock, "recursion");
	79	SPIN_BUG_ON(lock->owner_cpu == raw_smp_processor_id(),
	80	lock, "cpu recursion");
	81	}
	82
	83	static inline void debug_spin_lock_after(spinlock_t *lock)
	84	{
	85	lock->owner_cpu = raw_smp_processor_id();
	86	lock->owner = current;
	87	}
	88
	89	static inline void debug_spin_unlock(spinlock_t *lock)
	90	{
	91	SPIN_BUG_ON(lock->magic != SPINLOCK_MAGIC, lock, "bad magic");
	92	SPIN_BUG_ON(!spin_is_locked(lock), lock, "already unlocked");
	93	SPIN_BUG_ON(lock->owner != current, lock, "wrong owner");
	94	SPIN_BUG_ON(lock->owner_cpu != raw_smp_processor_id(),
	95	lock, "wrong CPU");
	96	lock->owner = SPINLOCK_OWNER_INIT;
	97	lock->owner_cpu = -1;
	98	}
	99
	100	static void __spin_lock_debug(spinlock_t *lock)
	101	{
fb1c8f93	102	u64 i;
c22f008b CE	103	u64 loops = loops_per_jiffy * HZ;
c22f008b CE	104	int print_once = 1;
fb1c8f93 IM	105
fb1c8f93 IM	106	for (;;) {
c22f008b	107	for (i = 0; i < loops; i++) {
fb1c8f93 IM	108	if (__raw_spin_trylock(&lock->raw_lock))
fb1c8f93 IM	109	return;
e0a60296	110	__delay(1);
fb1c8f93 IM	111	}
	112	/* lockup suspected: */
	113	if (print_once) {
	114	print_once = 0;
51989b9f DJ	115	printk(KERN_EMERG "BUG: spinlock lockup on CPU#%d, "
51989b9f DJ	116	"%s/%d, %p\n",
bb44f116 IM	117	raw_smp_processor_id(), current->comm,
bb44f116 IM	118	current->pid, lock);
fb1c8f93 IM	119	dump_stack();
	120	}
	121	}
	122	}
	123
	124	void _raw_spin_lock(spinlock_t *lock)
	125	{
	126	debug_spin_lock_before(lock);
	127	if (unlikely(!__raw_spin_trylock(&lock->raw_lock)))
	128	__spin_lock_debug(lock);
	129	debug_spin_lock_after(lock);
	130	}
	131
	132	int _raw_spin_trylock(spinlock_t *lock)
	133	{
	134	int ret = __raw_spin_trylock(&lock->raw_lock);
	135
	136	if (ret)
	137	debug_spin_lock_after(lock);
	138	#ifndef CONFIG_SMP
	139	/*
	140	* Must not happen on UP:
	141	*/
	142	SPIN_BUG_ON(!ret, lock, "trylock failure on UP");
	143	#endif
	144	return ret;
	145	}
	146
	147	void _raw_spin_unlock(spinlock_t *lock)
	148	{
	149	debug_spin_unlock(lock);
	150	__raw_spin_unlock(&lock->raw_lock);
	151	}
	152
	153	static void rwlock_bug(rwlock_t lock, const char msg)
	154	{
9a11b49a IM	155	if (!debug_locks_off())
	156	return;
	157
	158	printk(KERN_EMERG "BUG: rwlock %s on CPU#%d, %s/%d, %p\n",
	159	msg, raw_smp_processor_id(), current->comm,
	160	current->pid, lock);
	161	dump_stack();
fb1c8f93 IM	162	}
	163
	164	#define RWLOCK_BUG_ON(cond, lock, msg) if (unlikely(cond)) rwlock_bug(lock, msg)
	165
72f0b4e2	166	#if 0 /* __write_lock_debug() can lock up - maybe this can too? */
fb1c8f93 IM	167	static void __read_lock_debug(rwlock_t *lock)
fb1c8f93 IM	168	{
fb1c8f93	169	u64 i;
c22f008b CE	170	u64 loops = loops_per_jiffy * HZ;
c22f008b CE	171	int print_once = 1;
fb1c8f93 IM	172
fb1c8f93 IM	173	for (;;) {
c22f008b	174	for (i = 0; i < loops; i++) {
fb1c8f93 IM	175	if (__raw_read_trylock(&lock->raw_lock))
fb1c8f93 IM	176	return;
e0a60296	177	__delay(1);
fb1c8f93 IM	178	}
	179	/* lockup suspected: */
	180	if (print_once) {
	181	print_once = 0;
51989b9f DJ	182	printk(KERN_EMERG "BUG: read-lock lockup on CPU#%d, "
51989b9f DJ	183	"%s/%d, %p\n",
bb44f116 IM	184	raw_smp_processor_id(), current->comm,
bb44f116 IM	185	current->pid, lock);
fb1c8f93 IM	186	dump_stack();
	187	}
	188	}
	189	}
72f0b4e2	190	#endif
fb1c8f93 IM	191
	192	void _raw_read_lock(rwlock_t *lock)
	193	{
	194	RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
72f0b4e2	195	__raw_read_lock(&lock->raw_lock);
fb1c8f93 IM	196	}
	197
	198	int _raw_read_trylock(rwlock_t *lock)
	199	{
	200	int ret = __raw_read_trylock(&lock->raw_lock);
	201
	202	#ifndef CONFIG_SMP
	203	/*
	204	* Must not happen on UP:
	205	*/
	206	RWLOCK_BUG_ON(!ret, lock, "trylock failure on UP");
	207	#endif
	208	return ret;
	209	}
	210
	211	void _raw_read_unlock(rwlock_t *lock)
	212	{
	213	RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
	214	__raw_read_unlock(&lock->raw_lock);
	215	}
	216
	217	static inline void debug_write_lock_before(rwlock_t *lock)
	218	{
	219	RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
	220	RWLOCK_BUG_ON(lock->owner == current, lock, "recursion");
	221	RWLOCK_BUG_ON(lock->owner_cpu == raw_smp_processor_id(),
	222	lock, "cpu recursion");
	223	}
	224
	225	static inline void debug_write_lock_after(rwlock_t *lock)
	226	{
	227	lock->owner_cpu = raw_smp_processor_id();
	228	lock->owner = current;
	229	}
	230
	231	static inline void debug_write_unlock(rwlock_t *lock)
	232	{
	233	RWLOCK_BUG_ON(lock->magic != RWLOCK_MAGIC, lock, "bad magic");
	234	RWLOCK_BUG_ON(lock->owner != current, lock, "wrong owner");
	235	RWLOCK_BUG_ON(lock->owner_cpu != raw_smp_processor_id(),
	236	lock, "wrong CPU");
	237	lock->owner = SPINLOCK_OWNER_INIT;
	238	lock->owner_cpu = -1;
	239	}
	240
72f0b4e2	241	#if 0 /* This can cause lockups */
fb1c8f93 IM	242	static void __write_lock_debug(rwlock_t *lock)
fb1c8f93 IM	243	{
fb1c8f93	244	u64 i;
c22f008b CE	245	u64 loops = loops_per_jiffy * HZ;
c22f008b CE	246	int print_once = 1;
fb1c8f93 IM	247
fb1c8f93 IM	248	for (;;) {
c22f008b	249	for (i = 0; i < loops; i++) {
fb1c8f93 IM	250	if (__raw_write_trylock(&lock->raw_lock))
fb1c8f93 IM	251	return;
e0a60296	252	__delay(1);
fb1c8f93 IM	253	}
	254	/* lockup suspected: */
	255	if (print_once) {
	256	print_once = 0;
51989b9f DJ	257	printk(KERN_EMERG "BUG: write-lock lockup on CPU#%d, "
51989b9f DJ	258	"%s/%d, %p\n",
bb44f116 IM	259	raw_smp_processor_id(), current->comm,
bb44f116 IM	260	current->pid, lock);
fb1c8f93 IM	261	dump_stack();
	262	}
	263	}
	264	}
72f0b4e2	265	#endif
fb1c8f93 IM	266
	267	void _raw_write_lock(rwlock_t *lock)
	268	{
	269	debug_write_lock_before(lock);
72f0b4e2	270	__raw_write_lock(&lock->raw_lock);
fb1c8f93 IM	271	debug_write_lock_after(lock);
	272	}
	273
	274	int _raw_write_trylock(rwlock_t *lock)
	275	{
	276	int ret = __raw_write_trylock(&lock->raw_lock);
	277
	278	if (ret)
	279	debug_write_lock_after(lock);
	280	#ifndef CONFIG_SMP
	281	/*
	282	* Must not happen on UP:
	283	*/
	284	RWLOCK_BUG_ON(!ret, lock, "trylock failure on UP");
	285	#endif
	286	return ret;
	287	}
	288
	289	void _raw_write_unlock(rwlock_t *lock)
	290	{
	291	debug_write_unlock(lock);
	292	__raw_write_unlock(&lock->raw_lock);
	293	}