refcount.h revision fa9e4066f08beec538e775443c5be79dd423fcab
fa9e4066f08beec538e775443c5be79dd423fcabahrens/*
fa9e4066f08beec538e775443c5be79dd423fcabahrens * CDDL HEADER START
fa9e4066f08beec538e775443c5be79dd423fcabahrens *
fa9e4066f08beec538e775443c5be79dd423fcabahrens * The contents of this file are subject to the terms of the
fa9e4066f08beec538e775443c5be79dd423fcabahrens * Common Development and Distribution License, Version 1.0 only
fa9e4066f08beec538e775443c5be79dd423fcabahrens * (the "License"). You may not use this file except in compliance
fa9e4066f08beec538e775443c5be79dd423fcabahrens * 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/*
fa9e4066f08beec538e775443c5be79dd423fcabahrens * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
fa9e4066f08beec538e775443c5be79dd423fcabahrens * Use is subject to license terms.
fa9e4066f08beec538e775443c5be79dd423fcabahrens */
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens#ifndef _SYS_REFCOUNT_H
fa9e4066f08beec538e775443c5be79dd423fcabahrens#define _SYS_REFCOUNT_H
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens#pragma ident "%Z%%M% %I% %E% SMI"
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens#include <sys/inttypes.h>
fa9e4066f08beec538e775443c5be79dd423fcabahrens#include <sys/list.h>
fa9e4066f08beec538e775443c5be79dd423fcabahrens#include <sys/zfs_context.h>
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens#ifdef __cplusplus
fa9e4066f08beec538e775443c5be79dd423fcabahrensextern "C" {
fa9e4066f08beec538e775443c5be79dd423fcabahrens#endif
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens/*
fa9e4066f08beec538e775443c5be79dd423fcabahrens * If the reference is held only by the calling function and not any
fa9e4066f08beec538e775443c5be79dd423fcabahrens * particular object, use FTAG (which is a string) for the holder_tag.
fa9e4066f08beec538e775443c5be79dd423fcabahrens * Otherwise, use the object that holds the reference.
fa9e4066f08beec538e775443c5be79dd423fcabahrens */
fa9e4066f08beec538e775443c5be79dd423fcabahrens#define FTAG ((void*)__func__)
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens#if defined(DEBUG) || !defined(_KERNEL)
fa9e4066f08beec538e775443c5be79dd423fcabahrenstypedef struct reference {
fa9e4066f08beec538e775443c5be79dd423fcabahrens list_node_t ref_link;
fa9e4066f08beec538e775443c5be79dd423fcabahrens void *ref_holder;
fa9e4066f08beec538e775443c5be79dd423fcabahrens uint64_t ref_number;
fa9e4066f08beec538e775443c5be79dd423fcabahrens uint8_t *ref_removed;
fa9e4066f08beec538e775443c5be79dd423fcabahrens} reference_t;
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrenstypedef struct refcount {
fa9e4066f08beec538e775443c5be79dd423fcabahrens kmutex_t rc_mtx;
fa9e4066f08beec538e775443c5be79dd423fcabahrens list_t rc_list;
fa9e4066f08beec538e775443c5be79dd423fcabahrens list_t rc_removed;
fa9e4066f08beec538e775443c5be79dd423fcabahrens int64_t rc_count;
fa9e4066f08beec538e775443c5be79dd423fcabahrens int64_t rc_removed_count;
fa9e4066f08beec538e775443c5be79dd423fcabahrens} refcount_t;
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens/* Note: refcount_t should be initialized to zero before use. */
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrensvoid refcount_create(refcount_t *rc);
fa9e4066f08beec538e775443c5be79dd423fcabahrensvoid refcount_destroy(refcount_t *rc);
fa9e4066f08beec538e775443c5be79dd423fcabahrensvoid refcount_destroy_many(refcount_t *rc, uint64_t number);
fa9e4066f08beec538e775443c5be79dd423fcabahrensint refcount_is_zero(refcount_t *rc);
fa9e4066f08beec538e775443c5be79dd423fcabahrensint64_t refcount_count(refcount_t *rc);
fa9e4066f08beec538e775443c5be79dd423fcabahrensint64_t refcount_add(refcount_t *rc, void *holder_tag);
fa9e4066f08beec538e775443c5be79dd423fcabahrensint64_t refcount_remove(refcount_t *rc, void *holder_tag);
fa9e4066f08beec538e775443c5be79dd423fcabahrensint64_t refcount_add_many(refcount_t *rc, uint64_t number, void *holder_tag);
fa9e4066f08beec538e775443c5be79dd423fcabahrensint64_t refcount_remove_many(refcount_t *rc, uint64_t number, void *holder_tag);
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrensvoid refcount_init(void);
fa9e4066f08beec538e775443c5be79dd423fcabahrensvoid refcount_fini(void);
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens#else /* DEBUG */
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrenstypedef struct refcount {
fa9e4066f08beec538e775443c5be79dd423fcabahrens uint64_t rc_count;
fa9e4066f08beec538e775443c5be79dd423fcabahrens} refcount_t;
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens#define refcount_create(rc) ((rc)->rc_count = 0)
fa9e4066f08beec538e775443c5be79dd423fcabahrens#define refcount_destroy(rc) ((rc)->rc_count = 0)
fa9e4066f08beec538e775443c5be79dd423fcabahrens#define refcount_destroy_many(rc, number) ((rc)->rc_count = 0)
fa9e4066f08beec538e775443c5be79dd423fcabahrens#define refcount_is_zero(rc) ((rc)->rc_count == 0)
fa9e4066f08beec538e775443c5be79dd423fcabahrens#define refcount_count(rc) ((rc)->rc_count)
fa9e4066f08beec538e775443c5be79dd423fcabahrens#define refcount_add(rc, holder) atomic_add_64_nv(&(rc)->rc_count, 1)
fa9e4066f08beec538e775443c5be79dd423fcabahrens#define refcount_remove(rc, holder) atomic_add_64_nv(&(rc)->rc_count, -1)
fa9e4066f08beec538e775443c5be79dd423fcabahrens#define refcount_add_many(rc, number, holder) \
fa9e4066f08beec538e775443c5be79dd423fcabahrens atomic_add_64_nv(&(rc)->rc_count, number)
fa9e4066f08beec538e775443c5be79dd423fcabahrens#define refcount_remove_many(rc, number, holder) \
fa9e4066f08beec538e775443c5be79dd423fcabahrens atomic_add_64_nv(&(rc)->rc_count, -number)
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens#define refcount_init()
fa9e4066f08beec538e775443c5be79dd423fcabahrens#define refcount_fini()
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens#endif /* DEBUG */
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens#ifdef __cplusplus
fa9e4066f08beec538e775443c5be79dd423fcabahrens}
fa9e4066f08beec538e775443c5be79dd423fcabahrens#endif
fa9e4066f08beec538e775443c5be79dd423fcabahrens
fa9e4066f08beec538e775443c5be79dd423fcabahrens#endif /* _SYS_REFCOUNT_H */