about summary refs log tree commit diff
path: root/db2/lock/lock_region.c
diff options
context:
space:
mode:
Diffstat (limited to 'db2/lock/lock_region.c')
-rw-r--r--db2/lock/lock_region.c726
1 files changed, 726 insertions, 0 deletions
diff --git a/db2/lock/lock_region.c b/db2/lock/lock_region.c
new file mode 100644
index 0000000000..b597560744
--- /dev/null
+++ b/db2/lock/lock_region.c
@@ -0,0 +1,726 @@
+/*-
+ * See the file LICENSE for redistribution information.
+ *
+ * Copyright (c) 1996, 1997, 1998
+ *	Sleepycat Software.  All rights reserved.
+ */
+
+#include "config.h"
+
+#ifndef lint
+static const char sccsid[] = "@(#)lock_region.c	10.15 (Sleepycat) 6/2/98";
+#endif /* not lint */
+
+#ifndef NO_SYSTEM_INCLUDES
+#include <sys/types.h>
+
+#include <ctype.h>
+#include <errno.h>
+#include <string.h>
+#endif
+
+#include "db_int.h"
+#include "shqueue.h"
+#include "db_shash.h"
+#include "lock.h"
+#include "common_ext.h"
+
+static u_int32_t __lock_count_locks __P((DB_LOCKREGION *));
+static u_int32_t __lock_count_objs __P((DB_LOCKREGION *));
+static void	 __lock_dump_locker __P((DB_LOCKTAB *, DB_LOCKOBJ *, FILE *));
+static void	 __lock_dump_object __P((DB_LOCKTAB *, DB_LOCKOBJ *, FILE *));
+static const char *__lock_dump_status __P((db_status_t));
+static void	 __lock_reset_region __P((DB_LOCKTAB *));
+static int	 __lock_tabinit __P((DB_ENV *, DB_LOCKREGION *));
+
+int
+lock_open(path, flags, mode, dbenv, ltp)
+	const char *path;
+	u_int32_t flags;
+	int mode;
+	DB_ENV *dbenv;
+	DB_LOCKTAB **ltp;
+{
+	DB_LOCKTAB *lt;
+	u_int32_t lock_modes, maxlocks, regflags;
+	int ret;
+
+	/* Validate arguments. */
+#ifdef HAVE_SPINLOCKS
+#define	OKFLAGS	(DB_CREATE | DB_THREAD)
+#else
+#define	OKFLAGS	(DB_CREATE)
+#endif
+	if ((ret = __db_fchk(dbenv, "lock_open", flags, OKFLAGS)) != 0)
+		return (ret);
+
+	/* Create the lock table structure. */
+	if ((lt = (DB_LOCKTAB *)__db_calloc(1, sizeof(DB_LOCKTAB))) == NULL) {
+		__db_err(dbenv, "%s", strerror(ENOMEM));
+		return (ENOMEM);
+	}
+	lt->dbenv = dbenv;
+
+	/* Grab the values that we need to compute the region size. */
+	lock_modes = DB_LOCK_RW_N;
+	maxlocks = DB_LOCK_DEFAULT_N;
+	regflags = REGION_SIZEDEF;
+	if (dbenv != NULL) {
+		if (dbenv->lk_modes != 0) {
+			lock_modes = dbenv->lk_modes;
+			regflags = 0;
+		}
+		if (dbenv->lk_max != 0) {
+			maxlocks = dbenv->lk_max;
+			regflags = 0;
+		}
+	}
+
+	/* Join/create the lock region. */
+	lt->reginfo.dbenv = dbenv;
+	lt->reginfo.appname = DB_APP_NONE;
+	if (path == NULL)
+		lt->reginfo.path = NULL;
+	else
+		if ((lt->reginfo.path = (char *)__db_strdup(path)) == NULL)
+			goto err;
+	lt->reginfo.file = DB_DEFAULT_LOCK_FILE;
+	lt->reginfo.mode = mode;
+	lt->reginfo.size =
+	    LOCK_REGION_SIZE(lock_modes, maxlocks, __db_tablesize(maxlocks));
+	lt->reginfo.dbflags = flags;
+	lt->reginfo.addr = NULL;
+	lt->reginfo.fd = -1;
+	lt->reginfo.flags = regflags;
+
+	if ((ret = __db_rattach(&lt->reginfo)) != 0)
+		goto err;
+
+	/* Now set up the pointer to the region. */
+	lt->region = lt->reginfo.addr;
+
+	/* Initialize the region if we created it. */
+	if (F_ISSET(&lt->reginfo, REGION_CREATED)) {
+		lt->region->maxlocks = maxlocks;
+		lt->region->nmodes = lock_modes;
+		if ((ret = __lock_tabinit(dbenv, lt->region)) != 0)
+			goto err;
+	} else {
+		/* Check for an unexpected region. */
+		if (lt->region->magic != DB_LOCKMAGIC) {
+			__db_err(dbenv,
+			    "lock_open: %s: bad magic number", path);
+			ret = EINVAL;
+			goto err;
+		}
+	}
+
+	/* Check for automatic deadlock detection. */
+	if (dbenv != NULL && dbenv->lk_detect != DB_LOCK_NORUN) {
+		if (lt->region->detect != DB_LOCK_NORUN &&
+		    dbenv->lk_detect != DB_LOCK_DEFAULT &&
+		    lt->region->detect != dbenv->lk_detect) {
+			__db_err(dbenv,
+		    "lock_open: incompatible deadlock detector mode");
+			ret = EINVAL;
+			goto err;
+		}
+		if (lt->region->detect == DB_LOCK_NORUN)
+			lt->region->detect = dbenv->lk_detect;
+	}
+
+	/* Set up remaining pointers into region. */
+	lt->conflicts = (u_int8_t *)lt->region + sizeof(DB_LOCKREGION);
+	lt->hashtab =
+	    (DB_HASHTAB *)((u_int8_t *)lt->region + lt->region->hash_off);
+	lt->mem = (void *)((u_int8_t *)lt->region + lt->region->mem_off);
+
+	UNLOCK_LOCKREGION(lt);
+	*ltp = lt;
+	return (0);
+
+err:	if (lt->reginfo.addr != NULL) {
+		UNLOCK_LOCKREGION(lt);
+		(void)__db_rdetach(&lt->reginfo);
+		if (F_ISSET(&lt->reginfo, REGION_CREATED))
+			(void)lock_unlink(path, 1, dbenv);
+	}
+
+	if (lt->reginfo.path != NULL)
+		FREES(lt->reginfo.path);
+	FREE(lt, sizeof(*lt));
+	return (ret);
+}
+
+/*
+ * __lock_tabinit --
+ *	Initialize the lock region.
+ */
+static int
+__lock_tabinit(dbenv, lrp)
+	DB_ENV *dbenv;
+	DB_LOCKREGION *lrp;
+{
+	struct __db_lock *lp;
+	struct lock_header *tq_head;
+	struct obj_header *obj_head;
+	DB_LOCKOBJ *op;
+	u_int32_t i, nelements;
+	const u_int8_t *conflicts;
+	u_int8_t *curaddr;
+
+	conflicts = dbenv == NULL || dbenv->lk_conflicts == NULL ?
+	    db_rw_conflicts : dbenv->lk_conflicts;
+
+	lrp->table_size = __db_tablesize(lrp->maxlocks);
+	lrp->magic = DB_LOCKMAGIC;
+	lrp->version = DB_LOCKVERSION;
+	lrp->id = 0;
+	/*
+	 * These fields (lrp->maxlocks, lrp->nmodes) are initialized
+	 * in the caller, since we had to grab those values to size
+	 * the region.
+	 */
+	lrp->need_dd = 0;
+	lrp->detect = DB_LOCK_NORUN;
+	lrp->numobjs = lrp->maxlocks;
+	lrp->nlockers = 0;
+	lrp->mem_bytes = ALIGN(STRING_SIZE(lrp->maxlocks), sizeof(size_t));
+	lrp->increment = lrp->hdr.size / 2;
+	lrp->nconflicts = 0;
+	lrp->nrequests = 0;
+	lrp->nreleases = 0;
+	lrp->ndeadlocks = 0;
+
+	/*
+	 * As we write the region, we've got to maintain the alignment
+	 * for the structures that follow each chunk.  This information
+	 * ends up being encapsulated both in here as well as in the
+	 * lock.h file for the XXX_SIZE macros.
+	 */
+	/* Initialize conflict matrix. */
+	curaddr = (u_int8_t *)lrp + sizeof(DB_LOCKREGION);
+	memcpy(curaddr, conflicts, lrp->nmodes * lrp->nmodes);
+	curaddr += lrp->nmodes * lrp->nmodes;
+
+	/*
+	 * Initialize hash table.
+	 */
+	curaddr = (u_int8_t *)ALIGNP(curaddr, LOCK_HASH_ALIGN);
+	lrp->hash_off = curaddr - (u_int8_t *)lrp;
+	nelements = lrp->table_size;
+	__db_hashinit(curaddr, nelements);
+	curaddr += nelements * sizeof(DB_HASHTAB);
+
+	/*
+	 * Initialize locks onto a free list. Since locks contains mutexes,
+	 * we need to make sure that each lock is aligned on a MUTEX_ALIGNMENT
+	 * boundary.
+	 */
+	curaddr = (u_int8_t *)ALIGNP(curaddr, MUTEX_ALIGNMENT);
+	tq_head = &lrp->free_locks;
+	SH_TAILQ_INIT(tq_head);
+
+	for (i = 0; i++ < lrp->maxlocks;
+	    curaddr += ALIGN(sizeof(struct __db_lock), MUTEX_ALIGNMENT)) {
+		lp = (struct __db_lock *)curaddr;
+		lp->status = DB_LSTAT_FREE;
+		SH_TAILQ_INSERT_HEAD(tq_head, lp, links, __db_lock);
+	}
+
+	/* Initialize objects onto a free list.  */
+	obj_head = &lrp->free_objs;
+	SH_TAILQ_INIT(obj_head);
+
+	for (i = 0; i++ < lrp->maxlocks; curaddr += sizeof(DB_LOCKOBJ)) {
+		op = (DB_LOCKOBJ *)curaddr;
+		SH_TAILQ_INSERT_HEAD(obj_head, op, links, __db_lockobj);
+	}
+
+	/*
+	 * Initialize the string space; as for all shared memory allocation
+	 * regions, this requires size_t alignment, since we store the
+	 * lengths of malloc'd areas in the area.
+	 */
+	curaddr = (u_int8_t *)ALIGNP(curaddr, sizeof(size_t));
+	lrp->mem_off = curaddr - (u_int8_t *)lrp;
+	__db_shalloc_init(curaddr, lrp->mem_bytes);
+	return (0);
+}
+
+int
+lock_close(lt)
+	DB_LOCKTAB *lt;
+{
+	int ret;
+
+	if ((ret = __db_rdetach(&lt->reginfo)) != 0)
+		return (ret);
+
+	if (lt->reginfo.path != NULL)
+		FREES(lt->reginfo.path);
+	FREE(lt, sizeof(*lt));
+
+	return (0);
+}
+
+int
+lock_unlink(path, force, dbenv)
+	const char *path;
+	int force;
+	DB_ENV *dbenv;
+{
+	REGINFO reginfo;
+	int ret;
+
+	memset(&reginfo, 0, sizeof(reginfo));
+	reginfo.dbenv = dbenv;
+	reginfo.appname = DB_APP_NONE;
+	if (path != NULL && (reginfo.path = (char *)__db_strdup(path)) == NULL)
+		return (ENOMEM);
+	reginfo.file = DB_DEFAULT_LOCK_FILE;
+	ret = __db_runlink(&reginfo, force);
+	if (reginfo.path != NULL)
+		FREES(reginfo.path);
+	return (ret);
+}
+
+/*
+ * __lock_validate_region --
+ *	Called at every interface to verify if the region has changed size,
+ *	and if so, to remap the region in and reset the process' pointers.
+ *
+ * PUBLIC: int __lock_validate_region __P((DB_LOCKTAB *));
+ */
+int
+__lock_validate_region(lt)
+	DB_LOCKTAB *lt;
+{
+	int ret;
+
+	if (lt->reginfo.size == lt->region->hdr.size)
+		return (0);
+
+	/* Detach/reattach the region. */
+	if ((ret = __db_rreattach(&lt->reginfo, lt->region->hdr.size)) != 0)
+		return (ret);
+
+	/* Reset region information. */
+	lt->region = lt->reginfo.addr;
+	__lock_reset_region(lt);
+
+	return (0);
+}
+
+/*
+ * __lock_grow_region --
+ *	We have run out of space; time to grow the region.
+ *
+ * PUBLIC: int __lock_grow_region __P((DB_LOCKTAB *, int, size_t));
+ */
+int
+__lock_grow_region(lt, which, howmuch)
+	DB_LOCKTAB *lt;
+	int which;
+	size_t howmuch;
+{
+	struct __db_lock *newl;
+	struct lock_header *lock_head;
+	struct obj_header *obj_head;
+	DB_LOCKOBJ *op;
+	DB_LOCKREGION *lrp;
+	float lock_ratio, obj_ratio;
+	size_t incr, oldsize, used, usedmem;
+	u_int32_t i, newlocks, newmem, newobjs, usedlocks, usedobjs;
+	u_int8_t *curaddr;
+	int ret;
+
+	lrp = lt->region;
+	oldsize = lrp->hdr.size;
+	incr = lrp->increment;
+
+	/* Figure out how much of each sort of space we have. */
+	usedmem = lrp->mem_bytes - __db_shalloc_count(lt->mem);
+	usedobjs = lrp->numobjs - __lock_count_objs(lrp);
+	usedlocks = lrp->maxlocks - __lock_count_locks(lrp);
+
+	/*
+	 * Figure out what fraction of the used space belongs to each
+	 * different type of "thing" in the region.  Then partition the
+	 * new space up according to this ratio.
+	 */
+	used = usedmem +
+	    usedlocks * ALIGN(sizeof(struct __db_lock), MUTEX_ALIGNMENT) +
+	    usedobjs * sizeof(DB_LOCKOBJ);
+
+	lock_ratio = usedlocks *
+	    ALIGN(sizeof(struct __db_lock), MUTEX_ALIGNMENT) / (float)used;
+	obj_ratio = usedobjs * sizeof(DB_LOCKOBJ) / (float)used;
+
+	newlocks = (u_int32_t)(lock_ratio *
+	    incr / ALIGN(sizeof(struct __db_lock), MUTEX_ALIGNMENT));
+	newobjs = (u_int32_t)(obj_ratio * incr / sizeof(DB_LOCKOBJ));
+	newmem = incr -
+	    (newobjs * sizeof(DB_LOCKOBJ) +
+	    newlocks * ALIGN(sizeof(struct __db_lock), MUTEX_ALIGNMENT));
+
+	/*
+	 * Make sure we allocate enough memory for the object being
+	 * requested.
+	 */
+	switch (which) {
+	case DB_LOCK_LOCK:
+		if (newlocks == 0) {
+			newlocks = 10;
+			incr += newlocks * sizeof(struct __db_lock);
+		}
+		break;
+	case DB_LOCK_OBJ:
+		if (newobjs == 0) {
+			newobjs = 10;
+			incr += newobjs * sizeof(DB_LOCKOBJ);
+		}
+		break;
+	case DB_LOCK_MEM:
+		if (newmem < howmuch * 2) {
+			incr += howmuch * 2 - newmem;
+			newmem = howmuch * 2;
+		}
+		break;
+	}
+
+	newmem += ALIGN(incr, sizeof(size_t)) - incr;
+	incr = ALIGN(incr, sizeof(size_t));
+
+	/*
+	 * Since we are going to be allocating locks at the beginning of the
+	 * new chunk, we need to make sure that the chunk is MUTEX_ALIGNMENT
+	 * aligned.  We did not guarantee this when we created the region, so
+	 * we may need to pad the old region by extra bytes to ensure this
+	 * alignment.
+	 */
+	incr += ALIGN(oldsize, MUTEX_ALIGNMENT) - oldsize;
+
+	__db_err(lt->dbenv,
+	    "Growing lock region: %lu locks %lu objs %lu bytes",
+	    (u_long)newlocks, (u_long)newobjs, (u_long)newmem);
+
+	if ((ret = __db_rgrow(&lt->reginfo, oldsize + incr)) != 0)
+		return (ret);
+	lt->region = lt->reginfo.addr;
+	__lock_reset_region(lt);
+
+	/* Update region parameters. */
+	lrp = lt->region;
+	lrp->increment = incr << 1;
+	lrp->maxlocks += newlocks;
+	lrp->numobjs += newobjs;
+	lrp->mem_bytes += newmem;
+
+	curaddr = (u_int8_t *)lrp + oldsize;
+	curaddr = (u_int8_t *)ALIGNP(curaddr, MUTEX_ALIGNMENT);
+
+	/* Put new locks onto the free list. */
+	lock_head = &lrp->free_locks;
+	for (i = 0; i++ < newlocks;
+	    curaddr += ALIGN(sizeof(struct __db_lock), MUTEX_ALIGNMENT)) {
+		newl = (struct __db_lock *)curaddr;
+		SH_TAILQ_INSERT_HEAD(lock_head, newl, links, __db_lock);
+	}
+
+	/* Put new objects onto the free list.  */
+	obj_head = &lrp->free_objs;
+	for (i = 0; i++ < newobjs; curaddr += sizeof(DB_LOCKOBJ)) {
+		op = (DB_LOCKOBJ *)curaddr;
+		SH_TAILQ_INSERT_HEAD(obj_head, op, links, __db_lockobj);
+	}
+
+	*((size_t *)curaddr) = newmem - sizeof(size_t);
+	curaddr += sizeof(size_t);
+	__db_shalloc_free(lt->mem, curaddr);
+
+	return (0);
+}
+
+static void
+__lock_reset_region(lt)
+	DB_LOCKTAB *lt;
+{
+	lt->conflicts = (u_int8_t *)lt->region + sizeof(DB_LOCKREGION);
+	lt->hashtab =
+	    (DB_HASHTAB *)((u_int8_t *)lt->region + lt->region->hash_off);
+	lt->mem = (void *)((u_int8_t *)lt->region + lt->region->mem_off);
+}
+
+/*
+ * lock_stat --
+ *	Return LOCK statistics.
+ */
+int
+lock_stat(lt, gspp, db_malloc)
+	DB_LOCKTAB *lt;
+	DB_LOCK_STAT **gspp;
+	void *(*db_malloc) __P((size_t));
+{
+	DB_LOCKREGION *rp;
+
+	*gspp = NULL;
+
+	if ((*gspp = db_malloc == NULL ?
+	    (DB_LOCK_STAT *)__db_malloc(sizeof(**gspp)) :
+	    (DB_LOCK_STAT *)db_malloc(sizeof(**gspp))) == NULL)
+		return (ENOMEM);
+
+	/* Copy out the global statistics. */
+	LOCK_LOCKREGION(lt);
+
+	rp = lt->region;
+	(*gspp)->st_magic = rp->magic;
+	(*gspp)->st_version = rp->version;
+	(*gspp)->st_maxlocks = rp->maxlocks;
+	(*gspp)->st_nmodes = rp->nmodes;
+	(*gspp)->st_numobjs = rp->numobjs;
+	(*gspp)->st_nlockers = rp->nlockers;
+	(*gspp)->st_nconflicts = rp->nconflicts;
+	(*gspp)->st_nrequests = rp->nrequests;
+	(*gspp)->st_nreleases = rp->nreleases;
+	(*gspp)->st_ndeadlocks = rp->ndeadlocks;
+	(*gspp)->st_region_nowait = rp->hdr.lock.mutex_set_nowait;
+	(*gspp)->st_region_wait = rp->hdr.lock.mutex_set_wait;
+	(*gspp)->st_refcnt = rp->hdr.refcnt;
+	(*gspp)->st_regsize = rp->hdr.size;
+
+	UNLOCK_LOCKREGION(lt);
+
+	return (0);
+}
+
+static u_int32_t
+__lock_count_locks(lrp)
+	DB_LOCKREGION *lrp;
+{
+	struct __db_lock *newl;
+	u_int32_t count;
+
+	count = 0;
+	for (newl = SH_TAILQ_FIRST(&lrp->free_locks, __db_lock);
+	    newl != NULL;
+	    newl = SH_TAILQ_NEXT(newl, links, __db_lock))
+		count++;
+
+	return (count);
+}
+
+static u_int32_t
+__lock_count_objs(lrp)
+	DB_LOCKREGION *lrp;
+{
+	DB_LOCKOBJ *obj;
+	u_int32_t count;
+
+	count = 0;
+	for (obj = SH_TAILQ_FIRST(&lrp->free_objs, __db_lockobj);
+	    obj != NULL;
+	    obj = SH_TAILQ_NEXT(obj, links, __db_lockobj))
+		count++;
+
+	return (count);
+}
+
+#define	LOCK_DUMP_CONF		0x001		/* Conflict matrix. */
+#define	LOCK_DUMP_FREE		0x002		/* Display lock free list. */
+#define	LOCK_DUMP_LOCKERS	0x004		/* Display lockers. */
+#define	LOCK_DUMP_MEM		0x008		/* Display region memory. */
+#define	LOCK_DUMP_OBJECTS	0x010		/* Display objects. */
+#define	LOCK_DUMP_ALL		0x01f		/* Display all. */
+
+/*
+ * __lock_dump_region --
+ *
+ * PUBLIC: void __lock_dump_region __P((DB_LOCKTAB *, char *, FILE *));
+ */
+void
+__lock_dump_region(lt, area, fp)
+	DB_LOCKTAB *lt;
+	char *area;
+	FILE *fp;
+{
+	struct __db_lock *lp;
+	DB_LOCKOBJ *op;
+	DB_LOCKREGION *lrp;
+	u_int32_t flags, i, j;
+	int label;
+
+	/* Make it easy to call from the debugger. */
+	if (fp == NULL)
+		fp = stderr;
+
+	for (flags = 0; *area != '\0'; ++area)
+		switch (*area) {
+		case 'A':
+			LF_SET(LOCK_DUMP_ALL);
+			break;
+		case 'c':
+			LF_SET(LOCK_DUMP_CONF);
+			break;
+		case 'f':
+			LF_SET(LOCK_DUMP_FREE);
+			break;
+		case 'l':
+			LF_SET(LOCK_DUMP_LOCKERS);
+			break;
+		case 'm':
+			LF_SET(LOCK_DUMP_MEM);
+			break;
+		case 'o':
+			LF_SET(LOCK_DUMP_OBJECTS);
+			break;
+		}
+
+	lrp = lt->region;
+
+	fprintf(fp, "%s\nLock region parameters\n", DB_LINE);
+	fprintf(fp, "%s: %lu, %s: %lu, %s: %lu, %s: %lu\n%s: %lu, %s: %lu\n",
+	    "table size", (u_long)lrp->table_size,
+	    "hash_off", (u_long)lrp->hash_off,
+	    "increment", (u_long)lrp->increment,
+	    "mem_off", (u_long)lrp->mem_off,
+	    "mem_bytes", (u_long)lrp->mem_bytes,
+	    "need_dd", (u_long)lrp->need_dd);
+
+	if (LF_ISSET(LOCK_DUMP_CONF)) {
+		fprintf(fp, "\n%s\nConflict matrix\n", DB_LINE);
+		for (i = 0; i < lrp->nmodes; i++) {
+			for (j = 0; j < lrp->nmodes; j++)
+				fprintf(fp, "%lu\t",
+				    (u_long)lt->conflicts[i * lrp->nmodes + j]);
+			fprintf(fp, "\n");
+		}
+	}
+
+	if (LF_ISSET(LOCK_DUMP_LOCKERS | LOCK_DUMP_OBJECTS)) {
+		fprintf(fp, "%s\nLock hash buckets\n", DB_LINE);
+		for (i = 0; i < lrp->table_size; i++) {
+			label = 1;
+			for (op = SH_TAILQ_FIRST(&lt->hashtab[i], __db_lockobj);
+			    op != NULL;
+			    op = SH_TAILQ_NEXT(op, links, __db_lockobj)) {
+				if (LF_ISSET(LOCK_DUMP_LOCKERS) &&
+				    op->type == DB_LOCK_LOCKER) {
+					if (label) {
+						fprintf(fp,
+						    "Bucket %lu:\n", (u_long)i);
+						label = 0;
+					}
+					__lock_dump_locker(lt, op, fp);
+				}
+				if (LF_ISSET(LOCK_DUMP_OBJECTS) &&
+				    op->type == DB_LOCK_OBJTYPE) {
+					if (label) {
+						fprintf(fp,
+						    "Bucket %lu:\n", (u_long)i);
+						label = 0;
+					}
+					__lock_dump_object(lt, op, fp);
+				}
+			}
+		}
+	}
+
+	if (LF_ISSET(LOCK_DUMP_FREE)) {
+		fprintf(fp, "%s\nLock free list\n", DB_LINE);
+		for (lp = SH_TAILQ_FIRST(&lrp->free_locks, __db_lock);
+		    lp != NULL;
+		    lp = SH_TAILQ_NEXT(lp, links, __db_lock))
+			fprintf(fp, "0x%x: %lu\t%lu\t%s\t0x%x\n", (u_int)lp,
+			    (u_long)lp->holder, (u_long)lp->mode,
+			    __lock_dump_status(lp->status), (u_int)lp->obj);
+
+		fprintf(fp, "%s\nObject free list\n", DB_LINE);
+		for (op = SH_TAILQ_FIRST(&lrp->free_objs, __db_lockobj);
+		    op != NULL;
+		    op = SH_TAILQ_NEXT(op, links, __db_lockobj))
+			fprintf(fp, "0x%x\n", (u_int)op);
+	}
+
+	if (LF_ISSET(LOCK_DUMP_MEM))
+		__db_shalloc_dump(lt->mem, fp);
+}
+
+static void
+__lock_dump_locker(lt, op, fp)
+	DB_LOCKTAB *lt;
+	DB_LOCKOBJ *op;
+	FILE *fp;
+{
+	struct __db_lock *lp;
+	u_int32_t locker;
+	void *ptr;
+
+	ptr = SH_DBT_PTR(&op->lockobj);
+	memcpy(&locker, ptr, sizeof(u_int32_t));
+	fprintf(fp, "L %lx", (u_long)locker);
+
+	lp = SH_LIST_FIRST(&op->heldby, __db_lock);
+	if (lp == NULL) {
+		fprintf(fp, "\n");
+		return;
+	}
+	for (; lp != NULL; lp = SH_LIST_NEXT(lp, locker_links, __db_lock))
+		__lock_printlock(lt, lp, 0);
+}
+
+static void
+__lock_dump_object(lt, op, fp)
+	DB_LOCKTAB *lt;
+	DB_LOCKOBJ *op;
+	FILE *fp;
+{
+	struct __db_lock *lp;
+	u_int32_t j;
+	u_int8_t *ptr;
+	u_int ch;
+
+	ptr = SH_DBT_PTR(&op->lockobj);
+	for (j = 0; j < op->lockobj.size; ptr++, j++) {
+		ch = *ptr;
+		fprintf(fp, isprint(ch) ? "%c" : "\\%o", ch);
+	}
+	fprintf(fp, "\n");
+
+	fprintf(fp, "H:");
+	for (lp =
+	    SH_TAILQ_FIRST(&op->holders, __db_lock);
+	    lp != NULL;
+	    lp = SH_TAILQ_NEXT(lp, links, __db_lock))
+		__lock_printlock(lt, lp, 0);
+	lp = SH_TAILQ_FIRST(&op->waiters, __db_lock);
+	if (lp != NULL) {
+		fprintf(fp, "\nW:");
+		for (; lp != NULL; lp = SH_TAILQ_NEXT(lp, links, __db_lock))
+			__lock_printlock(lt, lp, 0);
+	}
+}
+
+static const char *
+__lock_dump_status(status)
+	db_status_t status;
+{
+	switch (status) {
+	case DB_LSTAT_ABORTED:
+		return ("aborted");
+	case DB_LSTAT_ERR:
+		return ("err");
+	case DB_LSTAT_FREE:
+		return ("free");
+	case DB_LSTAT_HELD:
+		return ("held");
+	case DB_LSTAT_NOGRANT:
+		return ("nogrant");
+	case DB_LSTAT_PENDING:
+		return ("pending");
+	case DB_LSTAT_WAITING:
+		return ("waiting");
+	}
+	return ("unknown status");
+}