xref: /illumos-gate/usr/src/uts/common/fs/zfs/sys/txg.h (revision c5bab7026b8e0ac44b25ee08507ea360f177d844)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 /*
26  * Copyright (c) 2012, 2017 by Delphix. All rights reserved.
27  */
28 
29 #ifndef _SYS_TXG_H
30 #define	_SYS_TXG_H
31 
32 #include <sys/spa.h>
33 #include <sys/zfs_context.h>
34 
35 #ifdef	__cplusplus
36 extern "C" {
37 #endif
38 
39 #define	TXG_CONCURRENT_STATES	3	/* open, quiescing, syncing	*/
40 #define	TXG_SIZE		4		/* next power of 2	*/
41 #define	TXG_MASK		(TXG_SIZE - 1)	/* mask for size	*/
42 #define	TXG_INITIAL		TXG_SIZE	/* initial txg 		*/
43 #define	TXG_IDX			(txg & TXG_MASK)
44 
45 /* Number of txgs worth of frees we defer adding to in-core spacemaps */
46 #define	TXG_DEFER_SIZE		2
47 
48 typedef struct tx_cpu tx_cpu_t;
49 
50 typedef struct txg_handle {
51 	tx_cpu_t	*th_cpu;
52 	uint64_t	th_txg;
53 } txg_handle_t;
54 
55 typedef struct txg_node {
56 	struct txg_node	*tn_next[TXG_SIZE];
57 	uint8_t		tn_member[TXG_SIZE];
58 } txg_node_t;
59 
60 typedef struct txg_list {
61 	kmutex_t	tl_lock;
62 	size_t		tl_offset;
63 	spa_t		*tl_spa;
64 	txg_node_t	*tl_head[TXG_SIZE];
65 } txg_list_t;
66 
67 struct dsl_pool;
68 
69 extern void txg_init(struct dsl_pool *dp, uint64_t txg);
70 extern void txg_fini(struct dsl_pool *dp);
71 extern void txg_sync_start(struct dsl_pool *dp);
72 extern void txg_sync_stop(struct dsl_pool *dp);
73 extern uint64_t txg_hold_open(struct dsl_pool *dp, txg_handle_t *txghp);
74 extern void txg_rele_to_quiesce(txg_handle_t *txghp);
75 extern void txg_rele_to_sync(txg_handle_t *txghp);
76 extern void txg_register_callbacks(txg_handle_t *txghp, list_t *tx_callbacks);
77 
78 extern void txg_delay(struct dsl_pool *dp, uint64_t txg, hrtime_t delta,
79     hrtime_t resolution);
80 extern void txg_kick(struct dsl_pool *dp);
81 
82 /*
83  * Wait until the given transaction group has finished syncing.
84  * Try to make this happen as soon as possible (eg. kick off any
85  * necessary syncs immediately).  If txg==0, wait for the currently open
86  * txg to finish syncing.
87  */
88 extern void txg_wait_synced(struct dsl_pool *dp, uint64_t txg);
89 
90 /*
91  * Wait until the given transaction group, or one after it, is
92  * the open transaction group.  Try to make this happen as soon
93  * as possible (eg. kick off any necessary syncs immediately).
94  * If txg == 0, wait for the next open txg.
95  */
96 extern void txg_wait_open(struct dsl_pool *dp, uint64_t txg);
97 
98 /*
99  * Returns TRUE if we are "backed up" waiting for the syncing
100  * transaction to complete; otherwise returns FALSE.
101  */
102 extern boolean_t txg_stalled(struct dsl_pool *dp);
103 
104 /* returns TRUE if someone is waiting for the next txg to sync */
105 extern boolean_t txg_sync_waiting(struct dsl_pool *dp);
106 
107 extern void txg_verify(spa_t *spa, uint64_t txg);
108 
109 /*
110  * Per-txg object lists.
111  */
112 
113 #define	TXG_CLEAN(txg)	((txg) - 1)
114 
115 extern void txg_list_create(txg_list_t *tl, spa_t *spa, size_t offset);
116 extern void txg_list_destroy(txg_list_t *tl);
117 extern boolean_t txg_list_empty(txg_list_t *tl, uint64_t txg);
118 extern boolean_t txg_all_lists_empty(txg_list_t *tl);
119 extern boolean_t txg_list_add(txg_list_t *tl, void *p, uint64_t txg);
120 extern boolean_t txg_list_add_tail(txg_list_t *tl, void *p, uint64_t txg);
121 extern void *txg_list_remove(txg_list_t *tl, uint64_t txg);
122 extern void *txg_list_remove_this(txg_list_t *tl, void *p, uint64_t txg);
123 extern boolean_t txg_list_member(txg_list_t *tl, void *p, uint64_t txg);
124 extern void *txg_list_head(txg_list_t *tl, uint64_t txg);
125 extern void *txg_list_next(txg_list_t *tl, void *p, uint64_t txg);
126 
127 #ifdef	__cplusplus
128 }
129 #endif
130 
131 #endif	/* _SYS_TXG_H */
132