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subr_lockdebug.c revision 1.10.2.3
      1  1.10.2.1   bouyer /*	$NetBSD: subr_lockdebug.c,v 1.10.2.3 2007/11/22 15:18:24 bouyer Exp $	*/
      2       1.2       ad 
      3       1.2       ad /*-
      4       1.2       ad  * Copyright (c) 2006, 2007 The NetBSD Foundation, Inc.
      5       1.2       ad  * All rights reserved.
      6       1.2       ad  *
      7       1.2       ad  * This code is derived from software contributed to The NetBSD Foundation
      8       1.2       ad  * by Andrew Doran.
      9       1.2       ad  *
     10       1.2       ad  * Redistribution and use in source and binary forms, with or without
     11       1.2       ad  * modification, are permitted provided that the following conditions
     12       1.2       ad  * are met:
     13       1.2       ad  * 1. Redistributions of source code must retain the above copyright
     14       1.2       ad  *    notice, this list of conditions and the following disclaimer.
     15       1.2       ad  * 2. Redistributions in binary form must reproduce the above copyright
     16       1.2       ad  *    notice, this list of conditions and the following disclaimer in the
     17       1.2       ad  *    documentation and/or other materials provided with the distribution.
     18       1.2       ad  * 3. All advertising materials mentioning features or use of this software
     19       1.2       ad  *    must display the following acknowledgement:
     20       1.2       ad  *	This product includes software developed by the NetBSD
     21       1.2       ad  *	Foundation, Inc. and its contributors.
     22       1.2       ad  * 4. Neither the name of The NetBSD Foundation nor the names of its
     23       1.2       ad  *    contributors may be used to endorse or promote products derived
     24       1.2       ad  *    from this software without specific prior written permission.
     25       1.2       ad  *
     26       1.2       ad  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     27       1.2       ad  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     28       1.2       ad  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     29       1.2       ad  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     30       1.2       ad  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     31       1.2       ad  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     32       1.2       ad  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     33       1.2       ad  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     34       1.2       ad  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     35       1.2       ad  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     36       1.2       ad  * POSSIBILITY OF SUCH DAMAGE.
     37       1.2       ad  */
     38       1.2       ad 
     39       1.2       ad /*
     40  1.10.2.1   bouyer  * Basic lock debugging code shared among lock primitives.
     41       1.2       ad  */
     42       1.2       ad 
     43       1.9      dsl #include <sys/cdefs.h>
     44  1.10.2.1   bouyer __KERNEL_RCSID(0, "$NetBSD: subr_lockdebug.c,v 1.10.2.3 2007/11/22 15:18:24 bouyer Exp $");
     45       1.9      dsl 
     46       1.2       ad #include "opt_multiprocessor.h"
     47       1.2       ad #include "opt_ddb.h"
     48       1.2       ad 
     49       1.2       ad #include <sys/param.h>
     50       1.2       ad #include <sys/proc.h>
     51       1.2       ad #include <sys/systm.h>
     52      1.10       ad #include <sys/kernel.h>
     53       1.2       ad #include <sys/kmem.h>
     54       1.2       ad #include <sys/lock.h>
     55       1.2       ad #include <sys/lockdebug.h>
     56       1.2       ad #include <sys/sleepq.h>
     57      1.10       ad #include <sys/cpu.h>
     58       1.2       ad 
     59  1.10.2.2   bouyer #include <lib/libkern/rb.h>
     60  1.10.2.2   bouyer 
     61       1.2       ad #ifdef LOCKDEBUG
     62       1.2       ad 
     63       1.2       ad #define	LD_BATCH_SHIFT	9
     64       1.2       ad #define	LD_BATCH	(1 << LD_BATCH_SHIFT)
     65       1.2       ad #define	LD_BATCH_MASK	(LD_BATCH - 1)
     66       1.2       ad #define	LD_MAX_LOCKS	1048576
     67       1.2       ad #define	LD_SLOP		16
     68       1.2       ad 
     69       1.2       ad #define	LD_LOCKED	0x01
     70       1.2       ad #define	LD_SLEEPER	0x02
     71       1.2       ad 
     72       1.2       ad typedef union lockdebuglk {
     73       1.2       ad 	struct {
     74       1.2       ad 		__cpu_simple_lock_t	lku_lock;
     75       1.2       ad 		int			lku_oldspl;
     76       1.2       ad 	} ul;
     77       1.2       ad 	uint8_t	lk_pad[64];
     78       1.2       ad } volatile __aligned(64) lockdebuglk_t;
     79       1.2       ad 
     80       1.2       ad #define	lk_lock		ul.lku_lock
     81       1.2       ad #define	lk_oldspl	ul.lku_oldspl
     82       1.2       ad 
     83       1.2       ad typedef struct lockdebug {
     84  1.10.2.2   bouyer 	struct rb_node	ld_rb_node;	/* must be the first member */
     85       1.2       ad 	_TAILQ_ENTRY(struct lockdebug, volatile) ld_chain;
     86       1.2       ad 	_TAILQ_ENTRY(struct lockdebug, volatile) ld_achain;
     87       1.2       ad 	volatile void	*ld_lock;
     88       1.2       ad 	lockops_t	*ld_lockops;
     89       1.2       ad 	struct lwp	*ld_lwp;
     90       1.2       ad 	uintptr_t	ld_locked;
     91       1.2       ad 	uintptr_t	ld_unlocked;
     92      1.10       ad 	uintptr_t	ld_initaddr;
     93       1.2       ad 	uint16_t	ld_shares;
     94       1.2       ad 	uint16_t	ld_cpu;
     95       1.2       ad 	uint8_t		ld_flags;
     96       1.2       ad 	uint8_t		ld_shwant;	/* advisory */
     97       1.2       ad 	uint8_t		ld_exwant;	/* advisory */
     98       1.2       ad 	uint8_t		ld_unused;
     99       1.2       ad } volatile lockdebug_t;
    100       1.2       ad 
    101       1.2       ad typedef _TAILQ_HEAD(lockdebuglist, struct lockdebug, volatile) lockdebuglist_t;
    102       1.2       ad 
    103  1.10.2.2   bouyer lockdebuglk_t		ld_tree_lk;
    104       1.2       ad lockdebuglk_t		ld_sleeper_lk;
    105       1.2       ad lockdebuglk_t		ld_spinner_lk;
    106       1.2       ad lockdebuglk_t		ld_free_lk;
    107       1.2       ad 
    108  1.10.2.1   bouyer lockdebuglist_t		ld_sleepers = TAILQ_HEAD_INITIALIZER(ld_sleepers);
    109  1.10.2.1   bouyer lockdebuglist_t		ld_spinners = TAILQ_HEAD_INITIALIZER(ld_spinners);
    110  1.10.2.1   bouyer lockdebuglist_t		ld_free = TAILQ_HEAD_INITIALIZER(ld_free);
    111  1.10.2.1   bouyer lockdebuglist_t		ld_all = TAILQ_HEAD_INITIALIZER(ld_all);
    112       1.2       ad int			ld_nfree;
    113       1.2       ad int			ld_freeptr;
    114       1.2       ad int			ld_recurse;
    115       1.5       ad bool			ld_nomore;
    116       1.2       ad lockdebug_t		*ld_table[LD_MAX_LOCKS / LD_BATCH];
    117       1.2       ad 
    118       1.2       ad lockdebug_t		ld_prime[LD_BATCH];
    119       1.2       ad 
    120       1.5       ad static void	lockdebug_abort1(lockdebug_t *, lockdebuglk_t *lk,
    121      1.10       ad 				 const char *, const char *, bool);
    122       1.5       ad static void	lockdebug_more(void);
    123       1.5       ad static void	lockdebug_init(void);
    124       1.2       ad 
    125  1.10.2.2   bouyer static signed int
    126  1.10.2.2   bouyer ld_rb_compare_nodes(const struct rb_node *n1, const struct rb_node *n2)
    127  1.10.2.2   bouyer {
    128  1.10.2.2   bouyer 	const lockdebug_t *ld1 = (const void *)n1;
    129  1.10.2.2   bouyer 	const lockdebug_t *ld2 = (const void *)n2;
    130  1.10.2.3   bouyer 	const uintptr_t a = (uintptr_t)ld1->ld_lock;
    131  1.10.2.3   bouyer 	const uintptr_t b = (uintptr_t)ld2->ld_lock;
    132  1.10.2.3   bouyer 
    133  1.10.2.3   bouyer 	if (a < b)
    134  1.10.2.2   bouyer 		return 1;
    135  1.10.2.3   bouyer 	if (a > b)
    136  1.10.2.3   bouyer 		return -1;
    137  1.10.2.2   bouyer 	return 0;
    138  1.10.2.2   bouyer }
    139  1.10.2.2   bouyer 
    140  1.10.2.2   bouyer static signed int
    141  1.10.2.2   bouyer ld_rb_compare_key(const struct rb_node *n, const void *key)
    142  1.10.2.2   bouyer {
    143  1.10.2.2   bouyer 	const lockdebug_t *ld = (const void *)n;
    144  1.10.2.3   bouyer 	const uintptr_t a = (uintptr_t)ld->ld_lock;
    145  1.10.2.3   bouyer 	const uintptr_t b = (uintptr_t)key;
    146  1.10.2.3   bouyer 
    147  1.10.2.3   bouyer 	if (a < b)
    148  1.10.2.2   bouyer 		return 1;
    149  1.10.2.3   bouyer 	if (a > b)
    150  1.10.2.3   bouyer 		return -1;
    151  1.10.2.2   bouyer 	return 0;
    152  1.10.2.2   bouyer }
    153  1.10.2.2   bouyer 
    154  1.10.2.2   bouyer static struct rb_tree ld_rb_tree;
    155  1.10.2.2   bouyer 
    156  1.10.2.2   bouyer static const struct rb_tree_ops ld_rb_tree_ops = {
    157  1.10.2.2   bouyer 	.rb_compare_nodes = ld_rb_compare_nodes,
    158  1.10.2.2   bouyer 	.rb_compare_key = ld_rb_compare_key,
    159  1.10.2.2   bouyer };
    160  1.10.2.2   bouyer 
    161       1.2       ad static inline void
    162       1.2       ad lockdebug_lock(lockdebuglk_t *lk)
    163       1.2       ad {
    164       1.2       ad 	int s;
    165       1.2       ad 
    166       1.8       ad 	s = splhigh();
    167       1.2       ad 	__cpu_simple_lock(&lk->lk_lock);
    168       1.2       ad 	lk->lk_oldspl = s;
    169       1.2       ad }
    170       1.2       ad 
    171       1.2       ad static inline void
    172       1.2       ad lockdebug_unlock(lockdebuglk_t *lk)
    173       1.2       ad {
    174       1.2       ad 	int s;
    175       1.2       ad 
    176       1.2       ad 	s = lk->lk_oldspl;
    177       1.2       ad 	__cpu_simple_unlock(&(lk->lk_lock));
    178       1.2       ad 	splx(s);
    179       1.2       ad }
    180       1.2       ad 
    181  1.10.2.2   bouyer static inline lockdebug_t *
    182  1.10.2.2   bouyer lockdebug_lookup1(volatile void *lock, lockdebuglk_t **lk)
    183      1.10       ad {
    184  1.10.2.2   bouyer 	lockdebug_t *ld;
    185  1.10.2.2   bouyer 
    186  1.10.2.2   bouyer 	lockdebug_lock(&ld_tree_lk);
    187  1.10.2.2   bouyer 	ld = (lockdebug_t *)rb_tree_find_node(&ld_rb_tree, __UNVOLATILE(lock));
    188  1.10.2.2   bouyer 	lockdebug_unlock(&ld_tree_lk);
    189  1.10.2.2   bouyer 	if (ld == NULL)
    190  1.10.2.2   bouyer 		return NULL;
    191  1.10.2.2   bouyer 
    192  1.10.2.2   bouyer 	if ((ld->ld_flags & LD_SLEEPER) != 0)
    193  1.10.2.2   bouyer 		*lk = &ld_sleeper_lk;
    194  1.10.2.2   bouyer 	else
    195  1.10.2.2   bouyer 		*lk = &ld_spinner_lk;
    196      1.10       ad 
    197      1.10       ad 	lockdebug_lock(*lk);
    198  1.10.2.2   bouyer 	return ld;
    199      1.10       ad }
    200      1.10       ad 
    201       1.2       ad /*
    202       1.2       ad  * lockdebug_lookup:
    203       1.2       ad  *
    204  1.10.2.2   bouyer  *	Find a lockdebug structure by a pointer to a lock and return it locked.
    205       1.2       ad  */
    206       1.2       ad static inline lockdebug_t *
    207  1.10.2.2   bouyer lockdebug_lookup(volatile void *lock, lockdebuglk_t **lk)
    208       1.2       ad {
    209  1.10.2.2   bouyer 	lockdebug_t *ld;
    210       1.2       ad 
    211  1.10.2.2   bouyer 	ld = lockdebug_lookup1(lock, lk);
    212  1.10.2.2   bouyer 	if (ld == NULL)
    213  1.10.2.2   bouyer 		panic("lockdebug_lookup: uninitialized lock (lock=%p)", lock);
    214       1.2       ad 	return ld;
    215       1.2       ad }
    216       1.2       ad 
    217       1.2       ad /*
    218       1.2       ad  * lockdebug_init:
    219       1.2       ad  *
    220       1.2       ad  *	Initialize the lockdebug system.  Allocate an initial pool of
    221       1.2       ad  *	lockdebug structures before the VM system is up and running.
    222       1.2       ad  */
    223       1.5       ad static void
    224       1.2       ad lockdebug_init(void)
    225       1.2       ad {
    226       1.2       ad 	lockdebug_t *ld;
    227       1.2       ad 	int i;
    228       1.2       ad 
    229  1.10.2.2   bouyer 	__cpu_simple_lock_init(&ld_tree_lk.lk_lock);
    230       1.2       ad 	__cpu_simple_lock_init(&ld_sleeper_lk.lk_lock);
    231       1.2       ad 	__cpu_simple_lock_init(&ld_spinner_lk.lk_lock);
    232       1.2       ad 	__cpu_simple_lock_init(&ld_free_lk.lk_lock);
    233       1.2       ad 
    234  1.10.2.2   bouyer 	rb_tree_init(&ld_rb_tree, &ld_rb_tree_ops);
    235  1.10.2.2   bouyer 
    236       1.2       ad 	ld = ld_prime;
    237       1.2       ad 	ld_table[0] = ld;
    238       1.2       ad 	for (i = 1, ld++; i < LD_BATCH; i++, ld++) {
    239       1.2       ad 		TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain);
    240       1.2       ad 		TAILQ_INSERT_TAIL(&ld_all, ld, ld_achain);
    241       1.2       ad 	}
    242       1.2       ad 	ld_freeptr = 1;
    243       1.2       ad 	ld_nfree = LD_BATCH - 1;
    244       1.2       ad }
    245       1.2       ad 
    246       1.2       ad /*
    247       1.2       ad  * lockdebug_alloc:
    248       1.2       ad  *
    249       1.2       ad  *	A lock is being initialized, so allocate an associated debug
    250       1.2       ad  *	structure.
    251       1.2       ad  */
    252  1.10.2.2   bouyer bool
    253      1.10       ad lockdebug_alloc(volatile void *lock, lockops_t *lo, uintptr_t initaddr)
    254       1.2       ad {
    255       1.2       ad 	struct cpu_info *ci;
    256       1.2       ad 	lockdebug_t *ld;
    257  1.10.2.2   bouyer 	lockdebuglk_t *lk;
    258       1.2       ad 
    259       1.5       ad 	if (lo == NULL || panicstr != NULL)
    260  1.10.2.2   bouyer 		return false;
    261       1.5       ad 	if (ld_freeptr == 0)
    262       1.5       ad 		lockdebug_init();
    263       1.2       ad 
    264  1.10.2.2   bouyer 	if ((ld = lockdebug_lookup1(lock, &lk)) != NULL) {
    265  1.10.2.2   bouyer 		lockdebug_abort1(ld, lk, __func__, "already initialized", true);
    266  1.10.2.2   bouyer 		/* NOTREACHED */
    267  1.10.2.2   bouyer 	}
    268  1.10.2.2   bouyer 
    269       1.2       ad 	ci = curcpu();
    270       1.2       ad 
    271       1.2       ad 	/*
    272       1.2       ad 	 * Pinch a new debug structure.  We may recurse because we call
    273       1.2       ad 	 * kmem_alloc(), which may need to initialize new locks somewhere
    274       1.7    skrll 	 * down the path.  If not recursing, we try to maintain at least
    275       1.2       ad 	 * LD_SLOP structures free, which should hopefully be enough to
    276       1.2       ad 	 * satisfy kmem_alloc().  If we can't provide a structure, not to
    277       1.2       ad 	 * worry: we'll just mark the lock as not having an ID.
    278       1.2       ad 	 */
    279       1.2       ad 	lockdebug_lock(&ld_free_lk);
    280       1.2       ad 	ci->ci_lkdebug_recurse++;
    281       1.2       ad 
    282       1.2       ad 	if (TAILQ_EMPTY(&ld_free)) {
    283       1.5       ad 		if (ci->ci_lkdebug_recurse > 1 || ld_nomore) {
    284       1.2       ad 			ci->ci_lkdebug_recurse--;
    285       1.2       ad 			lockdebug_unlock(&ld_free_lk);
    286  1.10.2.2   bouyer 			return false;
    287       1.2       ad 		}
    288       1.2       ad 		lockdebug_more();
    289       1.2       ad 	} else if (ci->ci_lkdebug_recurse == 1 && ld_nfree < LD_SLOP)
    290       1.2       ad 		lockdebug_more();
    291       1.2       ad 
    292       1.2       ad 	if ((ld = TAILQ_FIRST(&ld_free)) == NULL) {
    293       1.2       ad 		lockdebug_unlock(&ld_free_lk);
    294  1.10.2.2   bouyer 		return false;
    295       1.2       ad 	}
    296       1.2       ad 
    297       1.2       ad 	TAILQ_REMOVE(&ld_free, ld, ld_chain);
    298       1.2       ad 	ld_nfree--;
    299       1.2       ad 
    300       1.2       ad 	ci->ci_lkdebug_recurse--;
    301       1.2       ad 	lockdebug_unlock(&ld_free_lk);
    302       1.2       ad 
    303       1.2       ad 	if (ld->ld_lock != NULL)
    304       1.2       ad 		panic("lockdebug_alloc: corrupt table");
    305       1.2       ad 
    306       1.2       ad 	if (lo->lo_sleeplock)
    307       1.2       ad 		lockdebug_lock(&ld_sleeper_lk);
    308       1.2       ad 	else
    309       1.2       ad 		lockdebug_lock(&ld_spinner_lk);
    310       1.2       ad 
    311       1.2       ad 	/* Initialise the structure. */
    312       1.2       ad 	ld->ld_lock = lock;
    313       1.2       ad 	ld->ld_lockops = lo;
    314       1.2       ad 	ld->ld_locked = 0;
    315       1.2       ad 	ld->ld_unlocked = 0;
    316       1.2       ad 	ld->ld_lwp = NULL;
    317      1.10       ad 	ld->ld_initaddr = initaddr;
    318       1.2       ad 
    319  1.10.2.2   bouyer 	lockdebug_lock(&ld_tree_lk);
    320  1.10.2.2   bouyer 	rb_tree_insert_node(&ld_rb_tree, __UNVOLATILE(&ld->ld_rb_node));
    321  1.10.2.2   bouyer 	lockdebug_unlock(&ld_tree_lk);
    322  1.10.2.2   bouyer 
    323       1.2       ad 	if (lo->lo_sleeplock) {
    324       1.2       ad 		ld->ld_flags = LD_SLEEPER;
    325       1.2       ad 		lockdebug_unlock(&ld_sleeper_lk);
    326       1.2       ad 	} else {
    327       1.2       ad 		ld->ld_flags = 0;
    328       1.2       ad 		lockdebug_unlock(&ld_spinner_lk);
    329       1.2       ad 	}
    330       1.2       ad 
    331  1.10.2.2   bouyer 	return true;
    332       1.2       ad }
    333       1.2       ad 
    334       1.2       ad /*
    335       1.2       ad  * lockdebug_free:
    336       1.2       ad  *
    337       1.2       ad  *	A lock is being destroyed, so release debugging resources.
    338       1.2       ad  */
    339       1.2       ad void
    340  1.10.2.2   bouyer lockdebug_free(volatile void *lock)
    341       1.2       ad {
    342       1.2       ad 	lockdebug_t *ld;
    343       1.2       ad 	lockdebuglk_t *lk;
    344       1.2       ad 
    345       1.2       ad 	if (panicstr != NULL)
    346       1.2       ad 		return;
    347       1.2       ad 
    348  1.10.2.2   bouyer 	ld = lockdebug_lookup(lock, &lk);
    349  1.10.2.2   bouyer 	if (ld == NULL) {
    350       1.2       ad 		panic("lockdebug_free: destroying uninitialized lock %p"
    351  1.10.2.2   bouyer 		    "(ld_lock=%p)", lock, ld->ld_lock);
    352      1.10       ad 		lockdebug_abort1(ld, lk, __func__, "lock record follows",
    353      1.10       ad 		    true);
    354       1.2       ad 	}
    355       1.2       ad 	if ((ld->ld_flags & LD_LOCKED) != 0 || ld->ld_shares != 0)
    356      1.10       ad 		lockdebug_abort1(ld, lk, __func__, "is locked", true);
    357  1.10.2.2   bouyer 	lockdebug_lock(&ld_tree_lk);
    358  1.10.2.2   bouyer 	rb_tree_remove_node(&ld_rb_tree, __UNVOLATILE(&ld->ld_rb_node));
    359  1.10.2.2   bouyer 	lockdebug_unlock(&ld_tree_lk);
    360       1.2       ad 	ld->ld_lock = NULL;
    361       1.2       ad 	lockdebug_unlock(lk);
    362       1.2       ad 
    363       1.2       ad 	lockdebug_lock(&ld_free_lk);
    364       1.2       ad 	TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain);
    365       1.2       ad 	ld_nfree++;
    366       1.2       ad 	lockdebug_unlock(&ld_free_lk);
    367       1.2       ad }
    368       1.2       ad 
    369       1.2       ad /*
    370       1.2       ad  * lockdebug_more:
    371       1.2       ad  *
    372       1.2       ad  *	Allocate a batch of debug structures and add to the free list.
    373       1.2       ad  *	Must be called with ld_free_lk held.
    374       1.2       ad  */
    375       1.5       ad static void
    376       1.2       ad lockdebug_more(void)
    377       1.2       ad {
    378       1.2       ad 	lockdebug_t *ld;
    379       1.2       ad 	void *block;
    380       1.5       ad 	int i, base, m;
    381       1.2       ad 
    382       1.2       ad 	while (ld_nfree < LD_SLOP) {
    383       1.2       ad 		lockdebug_unlock(&ld_free_lk);
    384       1.2       ad 		block = kmem_zalloc(LD_BATCH * sizeof(lockdebug_t), KM_SLEEP);
    385       1.2       ad 		lockdebug_lock(&ld_free_lk);
    386       1.2       ad 
    387       1.2       ad 		if (block == NULL)
    388       1.2       ad 			return;
    389       1.2       ad 
    390       1.2       ad 		if (ld_nfree > LD_SLOP) {
    391       1.2       ad 			/* Somebody beat us to it. */
    392       1.2       ad 			lockdebug_unlock(&ld_free_lk);
    393       1.2       ad 			kmem_free(block, LD_BATCH * sizeof(lockdebug_t));
    394       1.2       ad 			lockdebug_lock(&ld_free_lk);
    395       1.2       ad 			continue;
    396       1.2       ad 		}
    397       1.2       ad 
    398       1.2       ad 		base = ld_freeptr;
    399       1.2       ad 		ld_nfree += LD_BATCH;
    400       1.2       ad 		ld = block;
    401       1.2       ad 		base <<= LD_BATCH_SHIFT;
    402       1.5       ad 		m = min(LD_MAX_LOCKS, base + LD_BATCH);
    403       1.5       ad 
    404       1.5       ad 		if (m == LD_MAX_LOCKS)
    405       1.5       ad 			ld_nomore = true;
    406       1.2       ad 
    407       1.5       ad 		for (i = base; i < m; i++, ld++) {
    408       1.2       ad 			TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain);
    409       1.2       ad 			TAILQ_INSERT_TAIL(&ld_all, ld, ld_achain);
    410       1.2       ad 		}
    411       1.2       ad 
    412       1.2       ad 		mb_write();
    413       1.2       ad 		ld_table[ld_freeptr++] = block;
    414       1.2       ad 	}
    415       1.2       ad }
    416       1.2       ad 
    417       1.2       ad /*
    418       1.2       ad  * lockdebug_wantlock:
    419       1.2       ad  *
    420       1.2       ad  *	Process the preamble to a lock acquire.
    421       1.2       ad  */
    422       1.2       ad void
    423  1.10.2.2   bouyer lockdebug_wantlock(volatile void *lock, uintptr_t where, int shared)
    424       1.2       ad {
    425       1.2       ad 	struct lwp *l = curlwp;
    426       1.2       ad 	lockdebuglk_t *lk;
    427       1.2       ad 	lockdebug_t *ld;
    428       1.3  thorpej 	bool recurse;
    429       1.2       ad 
    430       1.2       ad 	(void)shared;
    431       1.4  thorpej 	recurse = false;
    432       1.2       ad 
    433       1.2       ad 	if (panicstr != NULL)
    434       1.2       ad 		return;
    435       1.2       ad 
    436  1.10.2.2   bouyer 	if ((ld = lockdebug_lookup(lock, &lk)) == NULL)
    437       1.2       ad 		return;
    438       1.2       ad 
    439       1.2       ad 	if ((ld->ld_flags & LD_LOCKED) != 0) {
    440       1.2       ad 		if ((ld->ld_flags & LD_SLEEPER) != 0) {
    441       1.2       ad 			if (ld->ld_lwp == l)
    442       1.4  thorpej 				recurse = true;
    443       1.2       ad 		} else if (ld->ld_cpu == (uint16_t)cpu_number())
    444       1.4  thorpej 			recurse = true;
    445       1.2       ad 	}
    446       1.2       ad 
    447      1.10       ad #ifdef notyet
    448      1.10       ad 	if (cpu_intr_p()) {
    449      1.10       ad 		if ((ld->ld_flags & LD_SLEEPER) != 0)
    450      1.10       ad 			lockdebug_abort1(ld, lk, __func__,
    451      1.10       ad 			    "acquiring sleep lock from interrupt context",
    452      1.10       ad 			    true);
    453      1.10       ad 	}
    454      1.10       ad #endif
    455      1.10       ad 
    456       1.2       ad 	if (shared)
    457       1.2       ad 		ld->ld_shwant++;
    458       1.2       ad 	else
    459       1.2       ad 		ld->ld_exwant++;
    460       1.2       ad 
    461       1.2       ad 	if (recurse)
    462      1.10       ad 		lockdebug_abort1(ld, lk, __func__, "locking against myself",
    463      1.10       ad 		    true);
    464       1.2       ad 
    465       1.2       ad 	lockdebug_unlock(lk);
    466       1.2       ad }
    467       1.2       ad 
    468       1.2       ad /*
    469       1.2       ad  * lockdebug_locked:
    470       1.2       ad  *
    471       1.2       ad  *	Process a lock acquire operation.
    472       1.2       ad  */
    473       1.2       ad void
    474  1.10.2.2   bouyer lockdebug_locked(volatile void *lock, uintptr_t where, int shared)
    475       1.2       ad {
    476       1.2       ad 	struct lwp *l = curlwp;
    477       1.2       ad 	lockdebuglk_t *lk;
    478       1.2       ad 	lockdebug_t *ld;
    479       1.2       ad 
    480       1.2       ad 	if (panicstr != NULL)
    481       1.2       ad 		return;
    482       1.2       ad 
    483  1.10.2.2   bouyer 	if ((ld = lockdebug_lookup(lock, &lk)) == NULL)
    484       1.2       ad 		return;
    485       1.2       ad 
    486       1.2       ad 	if (shared) {
    487       1.2       ad 		l->l_shlocks++;
    488       1.2       ad 		ld->ld_shares++;
    489       1.2       ad 		ld->ld_shwant--;
    490       1.2       ad 	} else {
    491       1.2       ad 		if ((ld->ld_flags & LD_LOCKED) != 0)
    492       1.2       ad 			lockdebug_abort1(ld, lk, __func__,
    493      1.10       ad 			    "already locked", true);
    494       1.2       ad 
    495       1.2       ad 		ld->ld_flags |= LD_LOCKED;
    496       1.2       ad 		ld->ld_locked = where;
    497       1.2       ad 		ld->ld_cpu = (uint16_t)cpu_number();
    498       1.2       ad 		ld->ld_lwp = l;
    499       1.2       ad 		ld->ld_exwant--;
    500       1.2       ad 
    501       1.2       ad 		if ((ld->ld_flags & LD_SLEEPER) != 0) {
    502       1.2       ad 			l->l_exlocks++;
    503       1.2       ad 			TAILQ_INSERT_TAIL(&ld_sleepers, ld, ld_chain);
    504       1.2       ad 		} else {
    505       1.2       ad 			curcpu()->ci_spin_locks2++;
    506       1.2       ad 			TAILQ_INSERT_TAIL(&ld_spinners, ld, ld_chain);
    507       1.2       ad 		}
    508       1.2       ad 	}
    509       1.2       ad 
    510       1.2       ad 	lockdebug_unlock(lk);
    511       1.2       ad }
    512       1.2       ad 
    513       1.2       ad /*
    514       1.2       ad  * lockdebug_unlocked:
    515       1.2       ad  *
    516       1.2       ad  *	Process a lock release operation.
    517       1.2       ad  */
    518       1.2       ad void
    519  1.10.2.2   bouyer lockdebug_unlocked(volatile void *lock, uintptr_t where, int shared)
    520       1.2       ad {
    521       1.2       ad 	struct lwp *l = curlwp;
    522       1.2       ad 	lockdebuglk_t *lk;
    523       1.2       ad 	lockdebug_t *ld;
    524       1.2       ad 
    525       1.2       ad 	if (panicstr != NULL)
    526       1.2       ad 		return;
    527       1.2       ad 
    528  1.10.2.2   bouyer 	if ((ld = lockdebug_lookup(lock, &lk)) == NULL)
    529       1.2       ad 		return;
    530       1.2       ad 
    531       1.2       ad 	if (shared) {
    532       1.2       ad 		if (l->l_shlocks == 0)
    533       1.2       ad 			lockdebug_abort1(ld, lk, __func__,
    534      1.10       ad 			    "no shared locks held by LWP", true);
    535       1.2       ad 		if (ld->ld_shares == 0)
    536       1.2       ad 			lockdebug_abort1(ld, lk, __func__,
    537      1.10       ad 			    "no shared holds on this lock", true);
    538       1.2       ad 		l->l_shlocks--;
    539       1.2       ad 		ld->ld_shares--;
    540       1.2       ad 	} else {
    541       1.2       ad 		if ((ld->ld_flags & LD_LOCKED) == 0)
    542      1.10       ad 			lockdebug_abort1(ld, lk, __func__, "not locked",
    543      1.10       ad 			    true);
    544       1.2       ad 
    545       1.2       ad 		if ((ld->ld_flags & LD_SLEEPER) != 0) {
    546       1.2       ad 			if (ld->ld_lwp != curlwp)
    547       1.2       ad 				lockdebug_abort1(ld, lk, __func__,
    548      1.10       ad 				    "not held by current LWP", true);
    549       1.2       ad 			ld->ld_flags &= ~LD_LOCKED;
    550       1.2       ad 			ld->ld_unlocked = where;
    551       1.2       ad 			ld->ld_lwp = NULL;
    552       1.2       ad 			curlwp->l_exlocks--;
    553       1.2       ad 			TAILQ_REMOVE(&ld_sleepers, ld, ld_chain);
    554       1.2       ad 		} else {
    555       1.2       ad 			if (ld->ld_cpu != (uint16_t)cpu_number())
    556       1.2       ad 				lockdebug_abort1(ld, lk, __func__,
    557      1.10       ad 				    "not held by current CPU", true);
    558       1.2       ad 			ld->ld_flags &= ~LD_LOCKED;
    559       1.2       ad 			ld->ld_unlocked = where;
    560       1.2       ad 			ld->ld_lwp = NULL;
    561       1.2       ad 			curcpu()->ci_spin_locks2--;
    562       1.2       ad 			TAILQ_REMOVE(&ld_spinners, ld, ld_chain);
    563       1.2       ad 		}
    564       1.2       ad 	}
    565       1.2       ad 
    566       1.2       ad 	lockdebug_unlock(lk);
    567       1.2       ad }
    568       1.2       ad 
    569       1.2       ad /*
    570       1.2       ad  * lockdebug_barrier:
    571       1.2       ad  *
    572       1.2       ad  *	Panic if we hold more than one specified spin lock, and optionally,
    573       1.2       ad  *	if we hold sleep locks.
    574       1.2       ad  */
    575       1.2       ad void
    576       1.2       ad lockdebug_barrier(volatile void *spinlock, int slplocks)
    577       1.2       ad {
    578       1.2       ad 	struct lwp *l = curlwp;
    579       1.2       ad 	lockdebug_t *ld;
    580       1.2       ad 	uint16_t cpuno;
    581       1.2       ad 
    582       1.2       ad 	if (panicstr != NULL)
    583       1.2       ad 		return;
    584       1.2       ad 
    585       1.2       ad 	if (curcpu()->ci_spin_locks2 != 0) {
    586       1.2       ad 		cpuno = (uint16_t)cpu_number();
    587       1.2       ad 
    588       1.2       ad 		lockdebug_lock(&ld_spinner_lk);
    589       1.2       ad 		TAILQ_FOREACH(ld, &ld_spinners, ld_chain) {
    590       1.2       ad 			if (ld->ld_lock == spinlock) {
    591       1.2       ad 				if (ld->ld_cpu != cpuno)
    592       1.2       ad 					lockdebug_abort1(ld, &ld_spinner_lk,
    593       1.2       ad 					    __func__,
    594      1.10       ad 					    "not held by current CPU", true);
    595       1.2       ad 				continue;
    596       1.2       ad 			}
    597  1.10.2.1   bouyer 			if (ld->ld_cpu == cpuno && (l->l_pflag & LP_INTR) == 0)
    598       1.2       ad 				lockdebug_abort1(ld, &ld_spinner_lk,
    599      1.10       ad 				    __func__, "spin lock held", true);
    600       1.2       ad 		}
    601       1.2       ad 		lockdebug_unlock(&ld_spinner_lk);
    602       1.2       ad 	}
    603       1.2       ad 
    604       1.2       ad 	if (!slplocks) {
    605       1.2       ad 		if (l->l_exlocks != 0) {
    606       1.2       ad 			lockdebug_lock(&ld_sleeper_lk);
    607       1.2       ad 			TAILQ_FOREACH(ld, &ld_sleepers, ld_chain) {
    608       1.2       ad 				if (ld->ld_lwp == l)
    609       1.2       ad 					lockdebug_abort1(ld, &ld_sleeper_lk,
    610      1.10       ad 					    __func__, "sleep lock held", true);
    611       1.2       ad 			}
    612       1.2       ad 			lockdebug_unlock(&ld_sleeper_lk);
    613       1.2       ad 		}
    614       1.2       ad 		if (l->l_shlocks != 0)
    615       1.2       ad 			panic("lockdebug_barrier: holding %d shared locks",
    616       1.2       ad 			    l->l_shlocks);
    617       1.2       ad 	}
    618       1.2       ad }
    619       1.2       ad 
    620       1.2       ad /*
    621      1.10       ad  * lockdebug_mem_check:
    622      1.10       ad  *
    623      1.10       ad  *	Check for in-use locks within a memory region that is
    624  1.10.2.2   bouyer  *	being freed.
    625      1.10       ad  */
    626      1.10       ad void
    627      1.10       ad lockdebug_mem_check(const char *func, void *base, size_t sz)
    628      1.10       ad {
    629      1.10       ad 	lockdebug_t *ld;
    630  1.10.2.2   bouyer 	lockdebuglk_t *lk;
    631  1.10.2.2   bouyer 	uintptr_t lock;
    632      1.10       ad 
    633  1.10.2.2   bouyer 	lockdebug_lock(&ld_tree_lk);
    634  1.10.2.2   bouyer 	ld = (lockdebug_t *)rb_tree_find_node_geq(&ld_rb_tree, base);
    635  1.10.2.2   bouyer 	lockdebug_unlock(&ld_tree_lk);
    636  1.10.2.2   bouyer 	if (ld == NULL)
    637  1.10.2.2   bouyer 		return;
    638  1.10.2.2   bouyer 
    639  1.10.2.2   bouyer 	if ((ld->ld_flags & LD_SLEEPER) != 0)
    640  1.10.2.2   bouyer 		lk = &ld_sleeper_lk;
    641  1.10.2.2   bouyer 	else
    642  1.10.2.2   bouyer 		lk = &ld_spinner_lk;
    643      1.10       ad 
    644  1.10.2.2   bouyer 	lockdebug_lock(lk);
    645  1.10.2.2   bouyer 	lock = (uintptr_t)ld->ld_lock;
    646  1.10.2.2   bouyer 	if ((uintptr_t)base <= lock && lock < (uintptr_t)base + sz) {
    647  1.10.2.2   bouyer 		lockdebug_abort1(ld, lk, func,
    648  1.10.2.2   bouyer 		    "allocation contains active lock", !cold);
    649  1.10.2.2   bouyer 		return;
    650      1.10       ad 	}
    651      1.10       ad 	lockdebug_unlock(lk);
    652      1.10       ad }
    653      1.10       ad 
    654      1.10       ad /*
    655       1.2       ad  * lockdebug_dump:
    656       1.2       ad  *
    657       1.2       ad  *	Dump information about a lock on panic, or for DDB.
    658       1.2       ad  */
    659       1.2       ad static void
    660       1.2       ad lockdebug_dump(lockdebug_t *ld, void (*pr)(const char *, ...))
    661       1.2       ad {
    662       1.2       ad 	int sleeper = (ld->ld_flags & LD_SLEEPER);
    663       1.2       ad 
    664       1.2       ad 	(*pr)(
    665       1.2       ad 	    "lock address : %#018lx type     : %18s\n"
    666       1.2       ad 	    "shared holds : %18u exclusive: %18u\n"
    667       1.2       ad 	    "shares wanted: %18u exclusive: %18u\n"
    668       1.2       ad 	    "current cpu  : %18u last held: %18u\n"
    669       1.2       ad 	    "current lwp  : %#018lx last held: %#018lx\n"
    670      1.10       ad 	    "last locked  : %#018lx unlocked : %#018lx\n"
    671      1.10       ad 	    "initialized  : %#018lx\n",
    672       1.2       ad 	    (long)ld->ld_lock, (sleeper ? "sleep/adaptive" : "spin"),
    673       1.2       ad 	    (unsigned)ld->ld_shares, ((ld->ld_flags & LD_LOCKED) != 0),
    674       1.2       ad 	    (unsigned)ld->ld_shwant, (unsigned)ld->ld_exwant,
    675       1.2       ad 	    (unsigned)cpu_number(), (unsigned)ld->ld_cpu,
    676       1.2       ad 	    (long)curlwp, (long)ld->ld_lwp,
    677      1.10       ad 	    (long)ld->ld_locked, (long)ld->ld_unlocked,
    678      1.10       ad 	    (long)ld->ld_initaddr);
    679       1.2       ad 
    680       1.2       ad 	if (ld->ld_lockops->lo_dump != NULL)
    681       1.2       ad 		(*ld->ld_lockops->lo_dump)(ld->ld_lock);
    682       1.2       ad 
    683       1.2       ad 	if (sleeper) {
    684       1.2       ad 		(*pr)("\n");
    685       1.2       ad 		turnstile_print(ld->ld_lock, pr);
    686       1.2       ad 	}
    687       1.2       ad }
    688       1.2       ad 
    689       1.2       ad /*
    690       1.2       ad  * lockdebug_dump:
    691       1.2       ad  *
    692       1.2       ad  *	Dump information about a known lock.
    693       1.2       ad  */
    694       1.5       ad static void
    695       1.2       ad lockdebug_abort1(lockdebug_t *ld, lockdebuglk_t *lk, const char *func,
    696      1.10       ad 		 const char *msg, bool dopanic)
    697       1.2       ad {
    698       1.2       ad 
    699       1.2       ad 	printf_nolog("%s error: %s: %s\n\n", ld->ld_lockops->lo_name,
    700       1.2       ad 	    func, msg);
    701       1.2       ad 	lockdebug_dump(ld, printf_nolog);
    702       1.2       ad 	lockdebug_unlock(lk);
    703       1.2       ad 	printf_nolog("\n");
    704      1.10       ad 	if (dopanic)
    705      1.10       ad 		panic("LOCKDEBUG");
    706       1.2       ad }
    707       1.2       ad 
    708       1.2       ad #endif	/* LOCKDEBUG */
    709       1.2       ad 
    710       1.2       ad /*
    711       1.2       ad  * lockdebug_lock_print:
    712       1.2       ad  *
    713       1.2       ad  *	Handle the DDB 'show lock' command.
    714       1.2       ad  */
    715       1.2       ad #ifdef DDB
    716       1.2       ad void
    717       1.2       ad lockdebug_lock_print(void *addr, void (*pr)(const char *, ...))
    718       1.2       ad {
    719       1.2       ad #ifdef LOCKDEBUG
    720       1.2       ad 	lockdebug_t *ld;
    721       1.2       ad 
    722       1.2       ad 	TAILQ_FOREACH(ld, &ld_all, ld_achain) {
    723       1.2       ad 		if (ld->ld_lock == addr) {
    724       1.2       ad 			lockdebug_dump(ld, pr);
    725       1.2       ad 			return;
    726       1.2       ad 		}
    727       1.2       ad 	}
    728       1.2       ad 	(*pr)("Sorry, no record of a lock with address %p found.\n", addr);
    729       1.2       ad #else
    730       1.2       ad 	(*pr)("Sorry, kernel not built with the LOCKDEBUG option.\n");
    731       1.2       ad #endif	/* LOCKDEBUG */
    732       1.2       ad }
    733       1.2       ad #endif	/* DDB */
    734       1.2       ad 
    735       1.2       ad /*
    736       1.2       ad  * lockdebug_abort:
    737       1.2       ad  *
    738       1.2       ad  *	An error has been trapped - dump lock info and call panic().
    739       1.2       ad  */
    740       1.2       ad void
    741  1.10.2.2   bouyer lockdebug_abort(volatile void *lock, lockops_t *ops, const char *func,
    742  1.10.2.2   bouyer 		const char *msg)
    743       1.2       ad {
    744       1.2       ad #ifdef LOCKDEBUG
    745       1.2       ad 	lockdebug_t *ld;
    746       1.2       ad 	lockdebuglk_t *lk;
    747       1.2       ad 
    748  1.10.2.2   bouyer 	if ((ld = lockdebug_lookup(lock, &lk)) != NULL) {
    749      1.10       ad 		lockdebug_abort1(ld, lk, func, msg, true);
    750       1.2       ad 		/* NOTREACHED */
    751       1.2       ad 	}
    752       1.2       ad #endif	/* LOCKDEBUG */
    753       1.2       ad 
    754       1.2       ad 	printf_nolog("%s error: %s: %s\n\n"
    755       1.2       ad 	    "lock address : %#018lx\n"
    756       1.2       ad 	    "current cpu  : %18d\n"
    757       1.2       ad 	    "current lwp  : %#018lx\n",
    758       1.2       ad 	    ops->lo_name, func, msg, (long)lock, (int)cpu_number(),
    759       1.2       ad 	    (long)curlwp);
    760       1.2       ad 
    761       1.2       ad 	(*ops->lo_dump)(lock);
    762       1.2       ad 
    763       1.2       ad 	printf_nolog("\n");
    764       1.2       ad 	panic("lock error");
    765       1.2       ad }
    766