xref: /freebsd/sys/contrib/openzfs/include/sys/txg.h (revision 160a2ba804973e4b258c24247fa7c0cdc230dfb4)
1 // SPDX-License-Identifier: CDDL-1.0
2 /*
3  * CDDL HEADER START
4  *
5  * The contents of this file are subject to the terms of the
6  * Common Development and Distribution License (the "License").
7  * You may not use this file except in compliance with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or https://opensource.org/licenses/CDDL-1.0.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 /*
27  * Copyright (c) 2012, 2017 by Delphix. All rights reserved.
28  */
29 
30 #ifndef _SYS_TXG_H
31 #define	_SYS_TXG_H
32 
33 #include <sys/spa.h>
34 #include <sys/zfs_context.h>
35 
36 #ifdef	__cplusplus
37 extern "C" {
38 #endif
39 
40 #define	TXG_CONCURRENT_STATES	3	/* open, quiescing, syncing	*/
41 #define	TXG_SIZE		4		/* next power of 2	*/
42 #define	TXG_MASK		(TXG_SIZE - 1)	/* mask for size	*/
43 #define	TXG_INITIAL		TXG_SIZE	/* initial txg 		*/
44 #define	TXG_IDX			(txg & TXG_MASK)
45 #define	TXG_UNKNOWN		0
46 
47 /* Number of txgs worth of frees we defer adding to in-core spacemaps */
48 #define	TXG_DEFER_SIZE		2
49 
50 typedef struct tx_cpu tx_cpu_t;
51 
52 typedef struct txg_handle {
53 	tx_cpu_t	*th_cpu;
54 	uint64_t	th_txg;
55 } txg_handle_t;
56 
57 typedef struct txg_node {
58 	struct txg_node	*tn_next[TXG_SIZE];
59 	uint8_t		tn_member[TXG_SIZE];
60 } txg_node_t;
61 
62 typedef struct txg_list {
63 	kmutex_t	tl_lock;
64 	size_t		tl_offset;
65 	spa_t		*tl_spa;
66 	txg_node_t	*tl_head[TXG_SIZE];
67 } txg_list_t;
68 
69 struct dsl_pool;
70 
71 extern void txg_init(struct dsl_pool *dp, uint64_t txg);
72 extern void txg_fini(struct dsl_pool *dp);
73 extern void txg_sync_start(struct dsl_pool *dp);
74 extern void txg_sync_stop(struct dsl_pool *dp);
75 extern uint64_t txg_hold_open(struct dsl_pool *dp, txg_handle_t *txghp);
76 extern void txg_rele_to_quiesce(txg_handle_t *txghp);
77 extern void txg_rele_to_sync(txg_handle_t *txghp);
78 extern void txg_register_callbacks(txg_handle_t *txghp, list_t *tx_callbacks);
79 
80 extern void txg_delay(struct dsl_pool *dp, uint64_t txg, hrtime_t delta,
81     hrtime_t resolution);
82 extern void txg_kick(struct dsl_pool *dp, uint64_t txg);
83 
84 /*
85  * Wait until the given transaction group has finished syncing.
86  * Try to make this happen as soon as possible (eg. kick off any
87  * necessary syncs immediately).  If txg==0, wait for the currently open
88  * txg to finish syncing.
89  */
90 extern void txg_wait_synced(struct dsl_pool *dp, uint64_t txg);
91 
92 /*
93  * Wait as above. Returns true if the thread was signaled while waiting.
94  */
95 extern boolean_t txg_wait_synced_sig(struct dsl_pool *dp, uint64_t txg);
96 
97 /*
98  * Wait until the given transaction group, or one after it, is
99  * the open transaction group.  Try to make this happen as soon
100  * as possible (eg. kick off any necessary syncs immediately) when
101  * should_quiesce is set.  If txg == 0, wait for the next open txg.
102  */
103 extern void txg_wait_open(struct dsl_pool *dp, uint64_t txg,
104     boolean_t should_quiesce);
105 
106 /*
107  * Returns TRUE if we are "backed up" waiting for the syncing
108  * transaction to complete; otherwise returns FALSE.
109  */
110 extern boolean_t txg_stalled(struct dsl_pool *dp);
111 
112 /* returns TRUE if someone is waiting for the next txg to sync */
113 extern boolean_t txg_sync_waiting(struct dsl_pool *dp);
114 
115 extern void txg_verify(spa_t *spa, uint64_t txg);
116 
117 /*
118  * Wait for pending commit callbacks of already-synced transactions to finish
119  * processing.
120  */
121 extern void txg_wait_callbacks(struct dsl_pool *dp);
122 
123 /*
124  * Per-txg object lists.
125  */
126 
127 #define	TXG_CLEAN(txg)	((txg) - 1)
128 
129 extern void txg_list_create(txg_list_t *tl, spa_t *spa, size_t offset);
130 extern void txg_list_destroy(txg_list_t *tl);
131 extern boolean_t txg_list_empty(txg_list_t *tl, uint64_t txg);
132 extern boolean_t txg_all_lists_empty(txg_list_t *tl);
133 extern boolean_t txg_list_add(txg_list_t *tl, void *p, uint64_t txg);
134 extern boolean_t txg_list_add_tail(txg_list_t *tl, void *p, uint64_t txg);
135 extern void *txg_list_remove(txg_list_t *tl, uint64_t txg);
136 extern void *txg_list_remove_this(txg_list_t *tl, void *p, uint64_t txg);
137 extern boolean_t txg_list_member(txg_list_t *tl, void *p, uint64_t txg);
138 extern void *txg_list_head(txg_list_t *tl, uint64_t txg);
139 extern void *txg_list_next(txg_list_t *tl, void *p, uint64_t txg);
140 
141 /* Global tuning */
142 extern uint_t zfs_txg_timeout;
143 
144 
145 #ifdef ZFS_DEBUG
146 #define	TXG_VERIFY(spa, txg)		txg_verify(spa, txg)
147 #else
148 #define	TXG_VERIFY(spa, txg)
149 #endif
150 
151 #ifdef	__cplusplus
152 }
153 #endif
154 
155 #endif	/* _SYS_TXG_H */
156