fa9e4066f08beec538e775443c5be79dd423fcabahrens/*
fa9e4066f08beec538e775443c5be79dd423fcabahrens * CDDL HEADER START
fa9e4066f08beec538e775443c5be79dd423fcabahrens *
fa9e4066f08beec538e775443c5be79dd423fcabahrens * The contents of this file are subject to the terms of the
91ebeef555ce7f899b6270a3c2df47b51f7ad59aahrens * Common Development and Distribution License (the "License").
91ebeef555ce7f899b6270a3c2df47b51f7ad59aahrens * You may not use this file except in compliance with the License.
fa9e4066f08beec538e775443c5be79dd423fcabahrens *
fa9e4066f08beec538e775443c5be79dd423fcabahrens * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
fa9e4066f08beec538e775443c5be79dd423fcabahrens * or http://www.opensolaris.org/os/licensing.
fa9e4066f08beec538e775443c5be79dd423fcabahrens * See the License for the specific language governing permissions
fa9e4066f08beec538e775443c5be79dd423fcabahrens * and limitations under the License.
fa9e4066f08beec538e775443c5be79dd423fcabahrens *
fa9e4066f08beec538e775443c5be79dd423fcabahrens * When distributing Covered Code, include this CDDL HEADER in each
fa9e4066f08beec538e775443c5be79dd423fcabahrens * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
fa9e4066f08beec538e775443c5be79dd423fcabahrens * If applicable, add the following below this CDDL HEADER, with the
fa9e4066f08beec538e775443c5be79dd423fcabahrens * fields enclosed by brackets "[]" replaced with your own identifying
fa9e4066f08beec538e775443c5be79dd423fcabahrens * information: Portions Copyright [yyyy] [name of copyright owner]
fa9e4066f08beec538e775443c5be79dd423fcabahrens *
fa9e4066f08beec538e775443c5be79dd423fcabahrens * CDDL HEADER END
fa9e4066f08beec538e775443c5be79dd423fcabahrens */
fa9e4066f08beec538e775443c5be79dd423fcabahrens/*
3f9d6ad73e45c6823b409f93b0c8d4f62861d2d5Lin Ling * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson * Copyright (c) 2012, 2015 by Delphix. All rights reserved.
fa9e4066f08beec538e775443c5be79dd423fcabahrens */
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens#include <sys/zfs_context.h>
fa9e4066f08beec538e775443c5be79dd423fcabahrens#include <sys/refcount.h>
fa9e4066f08beec538e775443c5be79dd423fcabahrens
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson#ifdef ZFS_DEBUG
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens#ifdef _KERNEL
fa9e4066f08beec538e775443c5be79dd423fcabahrensint reference_tracking_enable = FALSE; /* runs out of memory too easily */
fa9e4066f08beec538e775443c5be79dd423fcabahrens#else
fa9e4066f08beec538e775443c5be79dd423fcabahrensint reference_tracking_enable = TRUE;
fa9e4066f08beec538e775443c5be79dd423fcabahrens#endif
3b2aab18808792cbd248a12f1edf139b89833c13Matthew Ahrensint reference_history = 3; /* tunable */
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrensstatic kmem_cache_t *reference_cache;
fa9e4066f08beec538e775443c5be79dd423fcabahrensstatic kmem_cache_t *reference_history_cache;
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrensvoid
fa9e4066f08beec538e775443c5be79dd423fcabahrensrefcount_init(void)
fa9e4066f08beec538e775443c5be79dd423fcabahrens{
fa9e4066f08beec538e775443c5be79dd423fcabahrens reference_cache = kmem_cache_create("reference_cache",
fa9e4066f08beec538e775443c5be79dd423fcabahrens sizeof (reference_t), 0, NULL, NULL, NULL, NULL, NULL, 0);
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens reference_history_cache = kmem_cache_create("reference_history_cache",
fa9e4066f08beec538e775443c5be79dd423fcabahrens sizeof (uint64_t), 0, NULL, NULL, NULL, NULL, NULL, 0);
fa9e4066f08beec538e775443c5be79dd423fcabahrens}
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrensvoid
fa9e4066f08beec538e775443c5be79dd423fcabahrensrefcount_fini(void)
fa9e4066f08beec538e775443c5be79dd423fcabahrens{
fa9e4066f08beec538e775443c5be79dd423fcabahrens kmem_cache_destroy(reference_cache);
fa9e4066f08beec538e775443c5be79dd423fcabahrens kmem_cache_destroy(reference_history_cache);
fa9e4066f08beec538e775443c5be79dd423fcabahrens}
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrensvoid
fa9e4066f08beec538e775443c5be79dd423fcabahrensrefcount_create(refcount_t *rc)
fa9e4066f08beec538e775443c5be79dd423fcabahrens{
91ebeef555ce7f899b6270a3c2df47b51f7ad59aahrens mutex_init(&rc->rc_mtx, NULL, MUTEX_DEFAULT, NULL);
fa9e4066f08beec538e775443c5be79dd423fcabahrens list_create(&rc->rc_list, sizeof (reference_t),
fa9e4066f08beec538e775443c5be79dd423fcabahrens offsetof(reference_t, ref_link));
fa9e4066f08beec538e775443c5be79dd423fcabahrens list_create(&rc->rc_removed, sizeof (reference_t),
fa9e4066f08beec538e775443c5be79dd423fcabahrens offsetof(reference_t, ref_link));
91ebeef555ce7f899b6270a3c2df47b51f7ad59aahrens rc->rc_count = 0;
91ebeef555ce7f899b6270a3c2df47b51f7ad59aahrens rc->rc_removed_count = 0;
3b2aab18808792cbd248a12f1edf139b89833c13Matthew Ahrens rc->rc_tracked = reference_tracking_enable;
3b2aab18808792cbd248a12f1edf139b89833c13Matthew Ahrens}
3b2aab18808792cbd248a12f1edf139b89833c13Matthew Ahrens
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilsonvoid
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilsonrefcount_create_tracked(refcount_t *rc)
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson{
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson refcount_create(rc);
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson rc->rc_tracked = B_TRUE;
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson}
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson
3b2aab18808792cbd248a12f1edf139b89833c13Matthew Ahrensvoid
3b2aab18808792cbd248a12f1edf139b89833c13Matthew Ahrensrefcount_create_untracked(refcount_t *rc)
3b2aab18808792cbd248a12f1edf139b89833c13Matthew Ahrens{
3b2aab18808792cbd248a12f1edf139b89833c13Matthew Ahrens refcount_create(rc);
3b2aab18808792cbd248a12f1edf139b89833c13Matthew Ahrens rc->rc_tracked = B_FALSE;
fa9e4066f08beec538e775443c5be79dd423fcabahrens}
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrensvoid
fa9e4066f08beec538e775443c5be79dd423fcabahrensrefcount_destroy_many(refcount_t *rc, uint64_t number)
fa9e4066f08beec538e775443c5be79dd423fcabahrens{
fa9e4066f08beec538e775443c5be79dd423fcabahrens reference_t *ref;
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens ASSERT(rc->rc_count == number);
fa9e4066f08beec538e775443c5be79dd423fcabahrens while (ref = list_head(&rc->rc_list)) {
fa9e4066f08beec538e775443c5be79dd423fcabahrens list_remove(&rc->rc_list, ref);
fa9e4066f08beec538e775443c5be79dd423fcabahrens kmem_cache_free(reference_cache, ref);
fa9e4066f08beec538e775443c5be79dd423fcabahrens }
fa9e4066f08beec538e775443c5be79dd423fcabahrens list_destroy(&rc->rc_list);
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens while (ref = list_head(&rc->rc_removed)) {
fa9e4066f08beec538e775443c5be79dd423fcabahrens list_remove(&rc->rc_removed, ref);
fa9e4066f08beec538e775443c5be79dd423fcabahrens kmem_cache_free(reference_history_cache, ref->ref_removed);
fa9e4066f08beec538e775443c5be79dd423fcabahrens kmem_cache_free(reference_cache, ref);
fa9e4066f08beec538e775443c5be79dd423fcabahrens }
fa9e4066f08beec538e775443c5be79dd423fcabahrens list_destroy(&rc->rc_removed);
fa9e4066f08beec538e775443c5be79dd423fcabahrens mutex_destroy(&rc->rc_mtx);
fa9e4066f08beec538e775443c5be79dd423fcabahrens}
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrensvoid
fa9e4066f08beec538e775443c5be79dd423fcabahrensrefcount_destroy(refcount_t *rc)
fa9e4066f08beec538e775443c5be79dd423fcabahrens{
fa9e4066f08beec538e775443c5be79dd423fcabahrens refcount_destroy_many(rc, 0);
fa9e4066f08beec538e775443c5be79dd423fcabahrens}
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrensint
fa9e4066f08beec538e775443c5be79dd423fcabahrensrefcount_is_zero(refcount_t *rc)
fa9e4066f08beec538e775443c5be79dd423fcabahrens{
fa9e4066f08beec538e775443c5be79dd423fcabahrens return (rc->rc_count == 0);
fa9e4066f08beec538e775443c5be79dd423fcabahrens}
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrensint64_t
fa9e4066f08beec538e775443c5be79dd423fcabahrensrefcount_count(refcount_t *rc)
fa9e4066f08beec538e775443c5be79dd423fcabahrens{
fa9e4066f08beec538e775443c5be79dd423fcabahrens return (rc->rc_count);
fa9e4066f08beec538e775443c5be79dd423fcabahrens}
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrensint64_t
fa9e4066f08beec538e775443c5be79dd423fcabahrensrefcount_add_many(refcount_t *rc, uint64_t number, void *holder)
fa9e4066f08beec538e775443c5be79dd423fcabahrens{
d5285cae913f4e01ffa0e6693a6d8ef1fbea30baGeorge Wilson reference_t *ref = NULL;
fa9e4066f08beec538e775443c5be79dd423fcabahrens int64_t count;
fa9e4066f08beec538e775443c5be79dd423fcabahrens
3b2aab18808792cbd248a12f1edf139b89833c13Matthew Ahrens if (rc->rc_tracked) {
fa9e4066f08beec538e775443c5be79dd423fcabahrens ref = kmem_cache_alloc(reference_cache, KM_SLEEP);
fa9e4066f08beec538e775443c5be79dd423fcabahrens ref->ref_holder = holder;
fa9e4066f08beec538e775443c5be79dd423fcabahrens ref->ref_number = number;
fa9e4066f08beec538e775443c5be79dd423fcabahrens }
fa9e4066f08beec538e775443c5be79dd423fcabahrens mutex_enter(&rc->rc_mtx);
fa9e4066f08beec538e775443c5be79dd423fcabahrens ASSERT(rc->rc_count >= 0);
3b2aab18808792cbd248a12f1edf139b89833c13Matthew Ahrens if (rc->rc_tracked)
fa9e4066f08beec538e775443c5be79dd423fcabahrens list_insert_head(&rc->rc_list, ref);
fa9e4066f08beec538e775443c5be79dd423fcabahrens rc->rc_count += number;
fa9e4066f08beec538e775443c5be79dd423fcabahrens count = rc->rc_count;
fa9e4066f08beec538e775443c5be79dd423fcabahrens mutex_exit(&rc->rc_mtx);
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens return (count);
fa9e4066f08beec538e775443c5be79dd423fcabahrens}
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrensint64_t
fa9e4066f08beec538e775443c5be79dd423fcabahrensrefcount_add(refcount_t *rc, void *holder)
fa9e4066f08beec538e775443c5be79dd423fcabahrens{
fa9e4066f08beec538e775443c5be79dd423fcabahrens return (refcount_add_many(rc, 1, holder));
fa9e4066f08beec538e775443c5be79dd423fcabahrens}
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrensint64_t
fa9e4066f08beec538e775443c5be79dd423fcabahrensrefcount_remove_many(refcount_t *rc, uint64_t number, void *holder)
fa9e4066f08beec538e775443c5be79dd423fcabahrens{
fa9e4066f08beec538e775443c5be79dd423fcabahrens reference_t *ref;
fa9e4066f08beec538e775443c5be79dd423fcabahrens int64_t count;
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens mutex_enter(&rc->rc_mtx);
fa9e4066f08beec538e775443c5be79dd423fcabahrens ASSERT(rc->rc_count >= number);
fa9e4066f08beec538e775443c5be79dd423fcabahrens
3b2aab18808792cbd248a12f1edf139b89833c13Matthew Ahrens if (!rc->rc_tracked) {
fa9e4066f08beec538e775443c5be79dd423fcabahrens rc->rc_count -= number;
fa9e4066f08beec538e775443c5be79dd423fcabahrens count = rc->rc_count;
fa9e4066f08beec538e775443c5be79dd423fcabahrens mutex_exit(&rc->rc_mtx);
fa9e4066f08beec538e775443c5be79dd423fcabahrens return (count);
fa9e4066f08beec538e775443c5be79dd423fcabahrens }
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens for (ref = list_head(&rc->rc_list); ref;
fa9e4066f08beec538e775443c5be79dd423fcabahrens ref = list_next(&rc->rc_list, ref)) {
fa9e4066f08beec538e775443c5be79dd423fcabahrens if (ref->ref_holder == holder && ref->ref_number == number) {
fa9e4066f08beec538e775443c5be79dd423fcabahrens list_remove(&rc->rc_list, ref);
fa9e4066f08beec538e775443c5be79dd423fcabahrens if (reference_history > 0) {
fa9e4066f08beec538e775443c5be79dd423fcabahrens ref->ref_removed =
fa9e4066f08beec538e775443c5be79dd423fcabahrens kmem_cache_alloc(reference_history_cache,
fa9e4066f08beec538e775443c5be79dd423fcabahrens KM_SLEEP);
fa9e4066f08beec538e775443c5be79dd423fcabahrens list_insert_head(&rc->rc_removed, ref);
fa9e4066f08beec538e775443c5be79dd423fcabahrens rc->rc_removed_count++;
3b2aab18808792cbd248a12f1edf139b89833c13Matthew Ahrens if (rc->rc_removed_count > reference_history) {
fa9e4066f08beec538e775443c5be79dd423fcabahrens ref = list_tail(&rc->rc_removed);
fa9e4066f08beec538e775443c5be79dd423fcabahrens list_remove(&rc->rc_removed, ref);
fa9e4066f08beec538e775443c5be79dd423fcabahrens kmem_cache_free(reference_history_cache,
fa9e4066f08beec538e775443c5be79dd423fcabahrens ref->ref_removed);
fa9e4066f08beec538e775443c5be79dd423fcabahrens kmem_cache_free(reference_cache, ref);
fa9e4066f08beec538e775443c5be79dd423fcabahrens rc->rc_removed_count--;
fa9e4066f08beec538e775443c5be79dd423fcabahrens }
fa9e4066f08beec538e775443c5be79dd423fcabahrens } else {
fa9e4066f08beec538e775443c5be79dd423fcabahrens kmem_cache_free(reference_cache, ref);
fa9e4066f08beec538e775443c5be79dd423fcabahrens }
fa9e4066f08beec538e775443c5be79dd423fcabahrens rc->rc_count -= number;
fa9e4066f08beec538e775443c5be79dd423fcabahrens count = rc->rc_count;
fa9e4066f08beec538e775443c5be79dd423fcabahrens mutex_exit(&rc->rc_mtx);
fa9e4066f08beec538e775443c5be79dd423fcabahrens return (count);
fa9e4066f08beec538e775443c5be79dd423fcabahrens }
fa9e4066f08beec538e775443c5be79dd423fcabahrens }
fa9e4066f08beec538e775443c5be79dd423fcabahrens panic("No such hold %p on refcount %llx", holder,
fa9e4066f08beec538e775443c5be79dd423fcabahrens (u_longlong_t)(uintptr_t)rc);
fa9e4066f08beec538e775443c5be79dd423fcabahrens return (-1);
fa9e4066f08beec538e775443c5be79dd423fcabahrens}
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrensint64_t
fa9e4066f08beec538e775443c5be79dd423fcabahrensrefcount_remove(refcount_t *rc, void *holder)
fa9e4066f08beec538e775443c5be79dd423fcabahrens{
fa9e4066f08beec538e775443c5be79dd423fcabahrens return (refcount_remove_many(rc, 1, holder));
fa9e4066f08beec538e775443c5be79dd423fcabahrens}
fa9e4066f08beec538e775443c5be79dd423fcabahrens
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Ericksonvoid
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Ericksonrefcount_transfer(refcount_t *dst, refcount_t *src)
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson{
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson int64_t count, removed_count;
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson list_t list, removed;
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson list_create(&list, sizeof (reference_t),
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson offsetof(reference_t, ref_link));
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson list_create(&removed, sizeof (reference_t),
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson offsetof(reference_t, ref_link));
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson mutex_enter(&src->rc_mtx);
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson count = src->rc_count;
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson removed_count = src->rc_removed_count;
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson src->rc_count = 0;
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson src->rc_removed_count = 0;
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson list_move_tail(&list, &src->rc_list);
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson list_move_tail(&removed, &src->rc_removed);
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson mutex_exit(&src->rc_mtx);
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson mutex_enter(&dst->rc_mtx);
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson dst->rc_count += count;
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson dst->rc_removed_count += removed_count;
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson list_move_tail(&dst->rc_list, &list);
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson list_move_tail(&dst->rc_removed, &removed);
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson mutex_exit(&dst->rc_mtx);
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson list_destroy(&list);
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson list_destroy(&removed);
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson}
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilsonvoid
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilsonrefcount_transfer_ownership(refcount_t *rc, void *current_holder,
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson void *new_holder)
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson{
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson reference_t *ref;
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson boolean_t found = B_FALSE;
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson mutex_enter(&rc->rc_mtx);
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson if (!rc->rc_tracked) {
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson mutex_exit(&rc->rc_mtx);
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson return;
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson }
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson for (ref = list_head(&rc->rc_list); ref;
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson ref = list_next(&rc->rc_list, ref)) {
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson if (ref->ref_holder == current_holder) {
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson ref->ref_holder = new_holder;
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson found = B_TRUE;
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson break;
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson }
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson }
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson ASSERT(found);
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson mutex_exit(&rc->rc_mtx);
dcbf3bd6a1f1360fc1afcee9e22c6dcff7844bf2George Wilson}
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson/*
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson * If tracking is enabled, return true if a reference exists that matches
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson * the "holder" tag. If tracking is disabled, then return true if a reference
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson * might be held.
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson */
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilsonboolean_t
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilsonrefcount_held(refcount_t *rc, void *holder)
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson{
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson reference_t *ref;
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson mutex_enter(&rc->rc_mtx);
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson if (!rc->rc_tracked) {
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson mutex_exit(&rc->rc_mtx);
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson return (rc->rc_count > 0);
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson }
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson for (ref = list_head(&rc->rc_list); ref;
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson ref = list_next(&rc->rc_list, ref)) {
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson if (ref->ref_holder == holder) {
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson mutex_exit(&rc->rc_mtx);
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson return (B_TRUE);
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson }
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson }
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson mutex_exit(&rc->rc_mtx);
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson return (B_FALSE);
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson}
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson/*
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson * If tracking is enabled, return true if a reference does not exist that
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson * matches the "holder" tag. If tracking is disabled, always return true
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson * since the reference might not be held.
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson */
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilsonboolean_t
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilsonrefcount_not_held(refcount_t *rc, void *holder)
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson{
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson reference_t *ref;
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson mutex_enter(&rc->rc_mtx);
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson if (!rc->rc_tracked) {
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson mutex_exit(&rc->rc_mtx);
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson return (B_TRUE);
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson }
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson for (ref = list_head(&rc->rc_list); ref;
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson ref = list_next(&rc->rc_list, ref)) {
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson if (ref->ref_holder == holder) {
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson mutex_exit(&rc->rc_mtx);
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson return (B_FALSE);
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson }
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson }
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson mutex_exit(&rc->rc_mtx);
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson return (B_TRUE);
0f7643c7376dd69a08acbfc9d1d7d548b10c846aGeorge Wilson}
744947dc83c634d985ed3ad79ac9c5e28d1865fdTom Erickson#endif /* ZFS_DEBUG */