860 lines
20 KiB
C
860 lines
20 KiB
C
/* $NetBSD: subr_lockdebug.c,v 1.45 2011/07/26 13:07:20 yamt Exp $ */
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/*-
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* Copyright (c) 2006, 2007, 2008 The NetBSD Foundation, Inc.
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* All rights reserved.
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*
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* This code is derived from software contributed to The NetBSD Foundation
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* by Andrew Doran.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
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* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
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* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
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* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*/
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/*
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* Basic lock debugging code shared among lock primitives.
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*/
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#include <sys/cdefs.h>
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__KERNEL_RCSID(0, "$NetBSD: subr_lockdebug.c,v 1.45 2011/07/26 13:07:20 yamt Exp $");
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#include "opt_ddb.h"
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#include <sys/param.h>
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#include <sys/proc.h>
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#include <sys/systm.h>
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#include <sys/kernel.h>
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#include <sys/kmem.h>
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#include <sys/lockdebug.h>
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#include <sys/sleepq.h>
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#include <sys/cpu.h>
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#include <sys/atomic.h>
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#include <sys/lock.h>
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#include <sys/rbtree.h>
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#include <machine/lock.h>
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unsigned int ld_panic;
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#ifdef LOCKDEBUG
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#define LD_BATCH_SHIFT 9
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#define LD_BATCH (1 << LD_BATCH_SHIFT)
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#define LD_BATCH_MASK (LD_BATCH - 1)
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#define LD_MAX_LOCKS 1048576
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#define LD_SLOP 16
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#define LD_LOCKED 0x01
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#define LD_SLEEPER 0x02
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#define LD_WRITE_LOCK 0x80000000
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typedef struct lockdebug {
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struct rb_node ld_rb_node;
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__cpu_simple_lock_t ld_spinlock;
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_TAILQ_ENTRY(struct lockdebug, volatile) ld_chain;
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_TAILQ_ENTRY(struct lockdebug, volatile) ld_achain;
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volatile void *ld_lock;
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lockops_t *ld_lockops;
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struct lwp *ld_lwp;
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uintptr_t ld_locked;
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uintptr_t ld_unlocked;
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uintptr_t ld_initaddr;
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uint16_t ld_shares;
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uint16_t ld_cpu;
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uint8_t ld_flags;
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uint8_t ld_shwant; /* advisory */
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uint8_t ld_exwant; /* advisory */
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uint8_t ld_unused;
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} volatile lockdebug_t;
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typedef _TAILQ_HEAD(lockdebuglist, struct lockdebug, volatile) lockdebuglist_t;
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__cpu_simple_lock_t ld_mod_lk;
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lockdebuglist_t ld_free = TAILQ_HEAD_INITIALIZER(ld_free);
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lockdebuglist_t ld_all = TAILQ_HEAD_INITIALIZER(ld_all);
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int ld_nfree;
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int ld_freeptr;
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int ld_recurse;
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bool ld_nomore;
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lockdebug_t ld_prime[LD_BATCH];
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static void lockdebug_abort1(lockdebug_t *, int, const char *,
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const char *, bool);
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static int lockdebug_more(int);
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static void lockdebug_init(void);
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static signed int
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ld_rbto_compare_nodes(void *ctx, const void *n1, const void *n2)
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{
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const lockdebug_t *ld1 = n1;
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const lockdebug_t *ld2 = n2;
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const uintptr_t a = (uintptr_t)ld1->ld_lock;
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const uintptr_t b = (uintptr_t)ld2->ld_lock;
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if (a < b)
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return -1;
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if (a > b)
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return 1;
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return 0;
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}
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static signed int
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ld_rbto_compare_key(void *ctx, const void *n, const void *key)
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{
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const lockdebug_t *ld = n;
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const uintptr_t a = (uintptr_t)ld->ld_lock;
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const uintptr_t b = (uintptr_t)key;
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if (a < b)
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return -1;
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if (a > b)
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return 1;
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return 0;
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}
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static rb_tree_t ld_rb_tree;
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static const rb_tree_ops_t ld_rb_tree_ops = {
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.rbto_compare_nodes = ld_rbto_compare_nodes,
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.rbto_compare_key = ld_rbto_compare_key,
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.rbto_node_offset = offsetof(lockdebug_t, ld_rb_node),
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.rbto_context = NULL
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};
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static inline lockdebug_t *
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lockdebug_lookup1(volatile void *lock)
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{
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lockdebug_t *ld;
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struct cpu_info *ci;
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ci = curcpu();
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__cpu_simple_lock(&ci->ci_data.cpu_ld_lock);
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ld = (lockdebug_t *)rb_tree_find_node(&ld_rb_tree, __UNVOLATILE(lock));
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__cpu_simple_unlock(&ci->ci_data.cpu_ld_lock);
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if (ld == NULL) {
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return NULL;
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}
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__cpu_simple_lock(&ld->ld_spinlock);
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return ld;
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}
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static void
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lockdebug_lock_cpus(void)
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{
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CPU_INFO_ITERATOR cii;
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struct cpu_info *ci;
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for (CPU_INFO_FOREACH(cii, ci)) {
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__cpu_simple_lock(&ci->ci_data.cpu_ld_lock);
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}
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}
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static void
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lockdebug_unlock_cpus(void)
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{
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CPU_INFO_ITERATOR cii;
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struct cpu_info *ci;
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for (CPU_INFO_FOREACH(cii, ci)) {
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__cpu_simple_unlock(&ci->ci_data.cpu_ld_lock);
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}
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}
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/*
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* lockdebug_lookup:
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*
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* Find a lockdebug structure by a pointer to a lock and return it locked.
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*/
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static inline lockdebug_t *
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lockdebug_lookup(volatile void *lock, uintptr_t where)
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{
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lockdebug_t *ld;
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ld = lockdebug_lookup1(lock);
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if (ld == NULL) {
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panic("lockdebug_lookup: uninitialized lock "
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"(lock=%p, from=%08"PRIxPTR")", lock, where);
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}
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return ld;
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}
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/*
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* lockdebug_init:
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*
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* Initialize the lockdebug system. Allocate an initial pool of
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* lockdebug structures before the VM system is up and running.
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*/
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static void
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lockdebug_init(void)
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{
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lockdebug_t *ld;
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int i;
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TAILQ_INIT(&curcpu()->ci_data.cpu_ld_locks);
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TAILQ_INIT(&curlwp->l_ld_locks);
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__cpu_simple_lock_init(&curcpu()->ci_data.cpu_ld_lock);
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__cpu_simple_lock_init(&ld_mod_lk);
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rb_tree_init(&ld_rb_tree, &ld_rb_tree_ops);
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ld = ld_prime;
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for (i = 1, ld++; i < LD_BATCH; i++, ld++) {
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__cpu_simple_lock_init(&ld->ld_spinlock);
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TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain);
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TAILQ_INSERT_TAIL(&ld_all, ld, ld_achain);
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}
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ld_freeptr = 1;
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ld_nfree = LD_BATCH - 1;
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}
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/*
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* lockdebug_alloc:
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*
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* A lock is being initialized, so allocate an associated debug
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* structure.
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*/
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bool
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lockdebug_alloc(volatile void *lock, lockops_t *lo, uintptr_t initaddr)
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{
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struct cpu_info *ci;
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lockdebug_t *ld;
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int s;
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if (lo == NULL || panicstr != NULL || ld_panic)
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return false;
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if (ld_freeptr == 0)
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lockdebug_init();
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s = splhigh();
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__cpu_simple_lock(&ld_mod_lk);
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if ((ld = lockdebug_lookup1(lock)) != NULL) {
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__cpu_simple_unlock(&ld_mod_lk);
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lockdebug_abort1(ld, s, __func__, "already initialized", true);
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return false;
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}
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/*
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* Pinch a new debug structure. We may recurse because we call
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* kmem_alloc(), which may need to initialize new locks somewhere
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* down the path. If not recursing, we try to maintain at least
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* LD_SLOP structures free, which should hopefully be enough to
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* satisfy kmem_alloc(). If we can't provide a structure, not to
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* worry: we'll just mark the lock as not having an ID.
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*/
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ci = curcpu();
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ci->ci_lkdebug_recurse++;
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if (TAILQ_EMPTY(&ld_free)) {
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if (ci->ci_lkdebug_recurse > 1 || ld_nomore) {
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ci->ci_lkdebug_recurse--;
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__cpu_simple_unlock(&ld_mod_lk);
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splx(s);
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return false;
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}
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s = lockdebug_more(s);
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} else if (ci->ci_lkdebug_recurse == 1 && ld_nfree < LD_SLOP) {
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s = lockdebug_more(s);
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}
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if ((ld = TAILQ_FIRST(&ld_free)) == NULL) {
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__cpu_simple_unlock(&ld_mod_lk);
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splx(s);
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return false;
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}
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TAILQ_REMOVE(&ld_free, ld, ld_chain);
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ld_nfree--;
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ci->ci_lkdebug_recurse--;
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if (ld->ld_lock != NULL) {
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panic("lockdebug_alloc: corrupt table");
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}
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/* Initialise the structure. */
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ld->ld_lock = lock;
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ld->ld_lockops = lo;
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ld->ld_locked = 0;
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ld->ld_unlocked = 0;
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ld->ld_lwp = NULL;
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ld->ld_initaddr = initaddr;
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ld->ld_flags = (lo->lo_type == LOCKOPS_SLEEP ? LD_SLEEPER : 0);
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lockdebug_lock_cpus();
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(void)rb_tree_insert_node(&ld_rb_tree, __UNVOLATILE(ld));
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lockdebug_unlock_cpus();
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__cpu_simple_unlock(&ld_mod_lk);
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splx(s);
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return true;
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}
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/*
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* lockdebug_free:
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*
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* A lock is being destroyed, so release debugging resources.
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*/
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void
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lockdebug_free(volatile void *lock)
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{
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lockdebug_t *ld;
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int s;
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if (panicstr != NULL || ld_panic)
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return;
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s = splhigh();
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__cpu_simple_lock(&ld_mod_lk);
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ld = lockdebug_lookup(lock, (uintptr_t) __builtin_return_address(0));
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if (ld == NULL) {
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__cpu_simple_unlock(&ld_mod_lk);
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panic("lockdebug_free: destroying uninitialized object %p"
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"(ld_lock=%p)", lock, ld->ld_lock);
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lockdebug_abort1(ld, s, __func__, "record follows", true);
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return;
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}
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if ((ld->ld_flags & LD_LOCKED) != 0 || ld->ld_shares != 0) {
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__cpu_simple_unlock(&ld_mod_lk);
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lockdebug_abort1(ld, s, __func__, "is locked or in use", true);
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return;
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}
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lockdebug_lock_cpus();
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rb_tree_remove_node(&ld_rb_tree, __UNVOLATILE(ld));
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lockdebug_unlock_cpus();
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ld->ld_lock = NULL;
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TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain);
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ld_nfree++;
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__cpu_simple_unlock(&ld->ld_spinlock);
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__cpu_simple_unlock(&ld_mod_lk);
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splx(s);
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}
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/*
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* lockdebug_more:
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*
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* Allocate a batch of debug structures and add to the free list.
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* Must be called with ld_mod_lk held.
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*/
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static int
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lockdebug_more(int s)
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{
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lockdebug_t *ld;
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void *block;
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int i, base, m;
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/*
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* Can't call kmem_alloc() if in interrupt context. XXX We could
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* deadlock, because we don't know which locks the caller holds.
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*/
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if (cpu_intr_p() || (curlwp->l_pflag & LP_INTR) != 0) {
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return s;
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}
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while (ld_nfree < LD_SLOP) {
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__cpu_simple_unlock(&ld_mod_lk);
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splx(s);
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block = kmem_zalloc(LD_BATCH * sizeof(lockdebug_t), KM_SLEEP);
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s = splhigh();
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__cpu_simple_lock(&ld_mod_lk);
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if (block == NULL)
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return s;
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if (ld_nfree > LD_SLOP) {
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/* Somebody beat us to it. */
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__cpu_simple_unlock(&ld_mod_lk);
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splx(s);
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kmem_free(block, LD_BATCH * sizeof(lockdebug_t));
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s = splhigh();
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__cpu_simple_lock(&ld_mod_lk);
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continue;
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}
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base = ld_freeptr;
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ld_nfree += LD_BATCH;
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ld = block;
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base <<= LD_BATCH_SHIFT;
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m = min(LD_MAX_LOCKS, base + LD_BATCH);
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if (m == LD_MAX_LOCKS)
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ld_nomore = true;
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for (i = base; i < m; i++, ld++) {
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__cpu_simple_lock_init(&ld->ld_spinlock);
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TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain);
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TAILQ_INSERT_TAIL(&ld_all, ld, ld_achain);
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}
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membar_producer();
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}
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return s;
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}
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/*
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* lockdebug_wantlock:
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*
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* Process the preamble to a lock acquire.
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*/
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void
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lockdebug_wantlock(volatile void *lock, uintptr_t where, bool shared,
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bool trylock)
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{
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struct lwp *l = curlwp;
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lockdebug_t *ld;
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bool recurse;
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int s;
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(void)shared;
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recurse = false;
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if (panicstr != NULL || ld_panic)
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return;
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s = splhigh();
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if ((ld = lockdebug_lookup(lock, where)) == NULL) {
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splx(s);
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return;
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}
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if ((ld->ld_flags & LD_LOCKED) != 0 || ld->ld_shares != 0) {
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if ((ld->ld_flags & LD_SLEEPER) != 0) {
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if (ld->ld_lwp == l && !(shared && trylock))
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recurse = true;
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} else if (ld->ld_cpu == (uint16_t)cpu_index(curcpu()))
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recurse = true;
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}
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if (cpu_intr_p()) {
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if ((ld->ld_flags & LD_SLEEPER) != 0) {
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lockdebug_abort1(ld, s, __func__,
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"acquiring sleep lock from interrupt context",
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true);
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return;
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}
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}
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if (shared)
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ld->ld_shwant++;
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else
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ld->ld_exwant++;
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if (recurse) {
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lockdebug_abort1(ld, s, __func__, "locking against myself",
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true);
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return;
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}
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__cpu_simple_unlock(&ld->ld_spinlock);
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splx(s);
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}
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/*
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* lockdebug_locked:
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*
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* Process a lock acquire operation.
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*/
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void
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lockdebug_locked(volatile void *lock, void *cvlock, uintptr_t where,
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int shared)
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{
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struct lwp *l = curlwp;
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lockdebug_t *ld;
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int s;
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if (panicstr != NULL || ld_panic)
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return;
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s = splhigh();
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if ((ld = lockdebug_lookup(lock, where)) == NULL) {
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splx(s);
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return;
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}
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if (cvlock) {
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KASSERT(ld->ld_lockops->lo_type == LOCKOPS_CV);
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if (lock == (void *)&lbolt) {
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/* nothing */
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} else if (ld->ld_shares++ == 0) {
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ld->ld_locked = (uintptr_t)cvlock;
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} else if (cvlock != (void *)ld->ld_locked) {
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lockdebug_abort1(ld, s, __func__, "multiple locks used"
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" with condition variable", true);
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return;
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}
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} else if (shared) {
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l->l_shlocks++;
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ld->ld_locked = where;
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ld->ld_shares++;
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ld->ld_shwant--;
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} else {
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if ((ld->ld_flags & LD_LOCKED) != 0) {
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lockdebug_abort1(ld, s, __func__, "already locked",
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true);
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return;
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}
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ld->ld_flags |= LD_LOCKED;
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ld->ld_locked = where;
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ld->ld_exwant--;
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if ((ld->ld_flags & LD_SLEEPER) != 0) {
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TAILQ_INSERT_TAIL(&l->l_ld_locks, ld, ld_chain);
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} else {
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TAILQ_INSERT_TAIL(&curcpu()->ci_data.cpu_ld_locks,
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ld, ld_chain);
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}
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}
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ld->ld_cpu = (uint16_t)cpu_index(curcpu());
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ld->ld_lwp = l;
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__cpu_simple_unlock(&ld->ld_spinlock);
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splx(s);
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}
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/*
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|
* lockdebug_unlocked:
|
|
*
|
|
* Process a lock release operation.
|
|
*/
|
|
void
|
|
lockdebug_unlocked(volatile void *lock, uintptr_t where, int shared)
|
|
{
|
|
struct lwp *l = curlwp;
|
|
lockdebug_t *ld;
|
|
int s;
|
|
|
|
if (panicstr != NULL || ld_panic)
|
|
return;
|
|
|
|
s = splhigh();
|
|
if ((ld = lockdebug_lookup(lock, where)) == NULL) {
|
|
splx(s);
|
|
return;
|
|
}
|
|
if (ld->ld_lockops->lo_type == LOCKOPS_CV) {
|
|
if (lock == (void *)&lbolt) {
|
|
/* nothing */
|
|
} else {
|
|
ld->ld_shares--;
|
|
}
|
|
} else if (shared) {
|
|
if (l->l_shlocks == 0) {
|
|
lockdebug_abort1(ld, s, __func__,
|
|
"no shared locks held by LWP", true);
|
|
return;
|
|
}
|
|
if (ld->ld_shares == 0) {
|
|
lockdebug_abort1(ld, s, __func__,
|
|
"no shared holds on this lock", true);
|
|
return;
|
|
}
|
|
l->l_shlocks--;
|
|
ld->ld_shares--;
|
|
if (ld->ld_lwp == l) {
|
|
ld->ld_unlocked = where;
|
|
ld->ld_lwp = NULL;
|
|
}
|
|
if (ld->ld_cpu == (uint16_t)cpu_index(curcpu()))
|
|
ld->ld_cpu = (uint16_t)-1;
|
|
} else {
|
|
if ((ld->ld_flags & LD_LOCKED) == 0) {
|
|
lockdebug_abort1(ld, s, __func__, "not locked", true);
|
|
return;
|
|
}
|
|
|
|
if ((ld->ld_flags & LD_SLEEPER) != 0) {
|
|
if (ld->ld_lwp != curlwp) {
|
|
lockdebug_abort1(ld, s, __func__,
|
|
"not held by current LWP", true);
|
|
return;
|
|
}
|
|
TAILQ_REMOVE(&l->l_ld_locks, ld, ld_chain);
|
|
} else {
|
|
if (ld->ld_cpu != (uint16_t)cpu_index(curcpu())) {
|
|
lockdebug_abort1(ld, s, __func__,
|
|
"not held by current CPU", true);
|
|
return;
|
|
}
|
|
TAILQ_REMOVE(&curcpu()->ci_data.cpu_ld_locks, ld,
|
|
ld_chain);
|
|
}
|
|
ld->ld_flags &= ~LD_LOCKED;
|
|
ld->ld_unlocked = where;
|
|
ld->ld_lwp = NULL;
|
|
}
|
|
__cpu_simple_unlock(&ld->ld_spinlock);
|
|
splx(s);
|
|
}
|
|
|
|
/*
|
|
* lockdebug_wakeup:
|
|
*
|
|
* Process a wakeup on a condition variable.
|
|
*/
|
|
void
|
|
lockdebug_wakeup(volatile void *lock, uintptr_t where)
|
|
{
|
|
lockdebug_t *ld;
|
|
int s;
|
|
|
|
if (panicstr != NULL || ld_panic || lock == (void *)&lbolt)
|
|
return;
|
|
|
|
s = splhigh();
|
|
/* Find the CV... */
|
|
if ((ld = lockdebug_lookup(lock, where)) == NULL) {
|
|
splx(s);
|
|
return;
|
|
}
|
|
/*
|
|
* If it has any waiters, ensure that they are using the
|
|
* same interlock.
|
|
*/
|
|
if (ld->ld_shares != 0 && !mutex_owned((kmutex_t *)ld->ld_locked)) {
|
|
lockdebug_abort1(ld, s, __func__, "interlocking mutex not "
|
|
"held during wakeup", true);
|
|
return;
|
|
}
|
|
__cpu_simple_unlock(&ld->ld_spinlock);
|
|
splx(s);
|
|
}
|
|
|
|
/*
|
|
* lockdebug_barrier:
|
|
*
|
|
* Panic if we hold more than one specified spin lock, and optionally,
|
|
* if we hold sleep locks.
|
|
*/
|
|
void
|
|
lockdebug_barrier(volatile void *spinlock, int slplocks)
|
|
{
|
|
struct lwp *l = curlwp;
|
|
lockdebug_t *ld;
|
|
int s;
|
|
|
|
if (panicstr != NULL || ld_panic)
|
|
return;
|
|
|
|
s = splhigh();
|
|
if ((l->l_pflag & LP_INTR) == 0) {
|
|
TAILQ_FOREACH(ld, &curcpu()->ci_data.cpu_ld_locks, ld_chain) {
|
|
if (ld->ld_lock == spinlock) {
|
|
continue;
|
|
}
|
|
__cpu_simple_lock(&ld->ld_spinlock);
|
|
lockdebug_abort1(ld, s, __func__,
|
|
"spin lock held", true);
|
|
return;
|
|
}
|
|
}
|
|
if (slplocks) {
|
|
splx(s);
|
|
return;
|
|
}
|
|
if ((ld = TAILQ_FIRST(&l->l_ld_locks)) != NULL) {
|
|
__cpu_simple_lock(&ld->ld_spinlock);
|
|
lockdebug_abort1(ld, s, __func__, "sleep lock held", true);
|
|
return;
|
|
}
|
|
splx(s);
|
|
if (l->l_shlocks != 0) {
|
|
panic("lockdebug_barrier: holding %d shared locks",
|
|
l->l_shlocks);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* lockdebug_mem_check:
|
|
*
|
|
* Check for in-use locks within a memory region that is
|
|
* being freed.
|
|
*/
|
|
void
|
|
lockdebug_mem_check(const char *func, void *base, size_t sz)
|
|
{
|
|
lockdebug_t *ld;
|
|
struct cpu_info *ci;
|
|
int s;
|
|
|
|
if (panicstr != NULL || ld_panic)
|
|
return;
|
|
|
|
s = splhigh();
|
|
ci = curcpu();
|
|
__cpu_simple_lock(&ci->ci_data.cpu_ld_lock);
|
|
ld = (lockdebug_t *)rb_tree_find_node_geq(&ld_rb_tree, base);
|
|
if (ld != NULL) {
|
|
const uintptr_t lock = (uintptr_t)ld->ld_lock;
|
|
|
|
if ((uintptr_t)base > lock)
|
|
panic("%s: corrupt tree ld=%p, base=%p, sz=%zu",
|
|
__func__, ld, base, sz);
|
|
if (lock >= (uintptr_t)base + sz)
|
|
ld = NULL;
|
|
}
|
|
__cpu_simple_unlock(&ci->ci_data.cpu_ld_lock);
|
|
if (ld != NULL) {
|
|
__cpu_simple_lock(&ld->ld_spinlock);
|
|
lockdebug_abort1(ld, s, func,
|
|
"allocation contains active lock", !cold);
|
|
return;
|
|
}
|
|
splx(s);
|
|
}
|
|
|
|
/*
|
|
* lockdebug_dump:
|
|
*
|
|
* Dump information about a lock on panic, or for DDB.
|
|
*/
|
|
static void
|
|
lockdebug_dump(lockdebug_t *ld, void (*pr)(const char *, ...))
|
|
{
|
|
int sleeper = (ld->ld_flags & LD_SLEEPER);
|
|
|
|
(*pr)(
|
|
"lock address : %#018lx type : %18s\n"
|
|
"initialized : %#018lx",
|
|
(long)ld->ld_lock, (sleeper ? "sleep/adaptive" : "spin"),
|
|
(long)ld->ld_initaddr);
|
|
|
|
if (ld->ld_lockops->lo_type == LOCKOPS_CV) {
|
|
(*pr)(" interlock: %#018lx\n", ld->ld_locked);
|
|
} else {
|
|
(*pr)("\n"
|
|
"shared holds : %18u exclusive: %18u\n"
|
|
"shares wanted: %18u exclusive: %18u\n"
|
|
"current cpu : %18u last held: %18u\n"
|
|
"current lwp : %#018lx last held: %#018lx\n"
|
|
"last locked%c : %#018lx unlocked%c: %#018lx\n",
|
|
(unsigned)ld->ld_shares, ((ld->ld_flags & LD_LOCKED) != 0),
|
|
(unsigned)ld->ld_shwant, (unsigned)ld->ld_exwant,
|
|
(unsigned)cpu_index(curcpu()), (unsigned)ld->ld_cpu,
|
|
(long)curlwp, (long)ld->ld_lwp,
|
|
((ld->ld_flags & LD_LOCKED) ? '*' : ' '),
|
|
(long)ld->ld_locked,
|
|
((ld->ld_flags & LD_LOCKED) ? ' ' : '*'),
|
|
(long)ld->ld_unlocked);
|
|
}
|
|
|
|
if (ld->ld_lockops->lo_dump != NULL)
|
|
(*ld->ld_lockops->lo_dump)(ld->ld_lock);
|
|
|
|
if (sleeper) {
|
|
(*pr)("\n");
|
|
turnstile_print(ld->ld_lock, pr);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* lockdebug_abort1:
|
|
*
|
|
* An error has been trapped - dump lock info and panic.
|
|
*/
|
|
static void
|
|
lockdebug_abort1(lockdebug_t *ld, int s, const char *func,
|
|
const char *msg, bool dopanic)
|
|
{
|
|
|
|
/*
|
|
* Don't make the situation wose if the system is already going
|
|
* down in flames. Once a panic is triggered, lockdebug state
|
|
* becomes stale and cannot be trusted.
|
|
*/
|
|
if (atomic_inc_uint_nv(&ld_panic) != 1) {
|
|
__cpu_simple_unlock(&ld->ld_spinlock);
|
|
splx(s);
|
|
return;
|
|
}
|
|
|
|
printf_nolog("%s error: %s: %s\n\n", ld->ld_lockops->lo_name,
|
|
func, msg);
|
|
lockdebug_dump(ld, printf_nolog);
|
|
__cpu_simple_unlock(&ld->ld_spinlock);
|
|
splx(s);
|
|
printf_nolog("\n");
|
|
if (dopanic)
|
|
panic("LOCKDEBUG");
|
|
}
|
|
|
|
#endif /* LOCKDEBUG */
|
|
|
|
/*
|
|
* lockdebug_lock_print:
|
|
*
|
|
* Handle the DDB 'show lock' command.
|
|
*/
|
|
#ifdef DDB
|
|
void
|
|
lockdebug_lock_print(void *addr, void (*pr)(const char *, ...))
|
|
{
|
|
#ifdef LOCKDEBUG
|
|
lockdebug_t *ld;
|
|
|
|
TAILQ_FOREACH(ld, &ld_all, ld_achain) {
|
|
if (ld->ld_lock == NULL)
|
|
continue;
|
|
if (addr == NULL || ld->ld_lock == addr) {
|
|
lockdebug_dump(ld, pr);
|
|
if (addr != NULL)
|
|
return;
|
|
}
|
|
}
|
|
if (addr != NULL) {
|
|
(*pr)("Sorry, no record of a lock with address %p found.\n",
|
|
addr);
|
|
}
|
|
#else
|
|
(*pr)("Sorry, kernel not built with the LOCKDEBUG option.\n");
|
|
#endif /* LOCKDEBUG */
|
|
}
|
|
#endif /* DDB */
|
|
|
|
/*
|
|
* lockdebug_abort:
|
|
*
|
|
* An error has been trapped - dump lock info and call panic().
|
|
*/
|
|
void
|
|
lockdebug_abort(volatile void *lock, lockops_t *ops, const char *func,
|
|
const char *msg)
|
|
{
|
|
#ifdef LOCKDEBUG
|
|
lockdebug_t *ld;
|
|
int s;
|
|
|
|
s = splhigh();
|
|
if ((ld = lockdebug_lookup(lock,
|
|
(uintptr_t) __builtin_return_address(0))) != NULL) {
|
|
lockdebug_abort1(ld, s, func, msg, true);
|
|
return;
|
|
}
|
|
splx(s);
|
|
#endif /* LOCKDEBUG */
|
|
|
|
/*
|
|
* Complain first on the occurrance only. Otherwise proceeed to
|
|
* panic where we will `rendezvous' with other CPUs if the machine
|
|
* is going down in flames.
|
|
*/
|
|
if (atomic_inc_uint_nv(&ld_panic) == 1) {
|
|
printf_nolog("%s error: %s: %s\n\n"
|
|
"lock address : %#018lx\n"
|
|
"current cpu : %18d\n"
|
|
"current lwp : %#018lx\n",
|
|
ops->lo_name, func, msg, (long)lock,
|
|
(int)cpu_index(curcpu()), (long)curlwp);
|
|
(*ops->lo_dump)(lock);
|
|
printf_nolog("\n");
|
|
}
|
|
|
|
panic("lock error");
|
|
}
|