xref: /freebsd/sys/contrib/openzfs/include/sys/txg.h (revision 8eb2bee6c0f4957c6c1cea826e59cda4d18a2a64)
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 #define	TXG_UNKNOWN		0
45 
46 /* Number of txgs worth of frees we defer adding to in-core spacemaps */
47 #define	TXG_DEFER_SIZE		2
48 
49 typedef struct tx_cpu tx_cpu_t;
50 
51 typedef struct txg_handle {
52 	tx_cpu_t	*th_cpu;
53 	uint64_t	th_txg;
54 } txg_handle_t;
55 
56 typedef struct txg_node {
57 	struct txg_node	*tn_next[TXG_SIZE];
58 	uint8_t		tn_member[TXG_SIZE];
59 } txg_node_t;
60 
61 typedef struct txg_list {
62 	kmutex_t	tl_lock;
63 	size_t		tl_offset;
64 	spa_t		*tl_spa;
65 	txg_node_t	*tl_head[TXG_SIZE];
66 } txg_list_t;
67 
68 struct dsl_pool;
69 
70 extern void txg_init(struct dsl_pool *dp, uint64_t txg);
71 extern void txg_fini(struct dsl_pool *dp);
72 extern void txg_sync_start(struct dsl_pool *dp);
73 extern void txg_sync_stop(struct dsl_pool *dp);
74 extern uint64_t txg_hold_open(struct dsl_pool *dp, txg_handle_t *txghp);
75 extern void txg_rele_to_quiesce(txg_handle_t *txghp);
76 extern void txg_rele_to_sync(txg_handle_t *txghp);
77 extern void txg_register_callbacks(txg_handle_t *txghp, list_t *tx_callbacks);
78 
79 extern void txg_delay(struct dsl_pool *dp, uint64_t txg, hrtime_t delta,
80     hrtime_t resolution);
81 extern void txg_kick(struct dsl_pool *dp, uint64_t txg);
82 
83 /*
84  * Wait until the given transaction group has finished syncing.
85  * Try to make this happen as soon as possible (eg. kick off any
86  * necessary syncs immediately).  If txg==0, wait for the currently open
87  * txg to finish syncing.
88  */
89 extern void txg_wait_synced(struct dsl_pool *dp, uint64_t txg);
90 
91 /*
92  * Wait as above. Returns true if the thread was signaled while waiting.
93  */
94 extern boolean_t txg_wait_synced_sig(struct dsl_pool *dp, uint64_t txg);
95 
96 /*
97  * Wait until the given transaction group, or one after it, is
98  * the open transaction group.  Try to make this happen as soon
99  * as possible (eg. kick off any necessary syncs immediately) when
100  * should_quiesce is set.  If txg == 0, wait for the next open txg.
101  */
102 extern void txg_wait_open(struct dsl_pool *dp, uint64_t txg,
103     boolean_t should_quiesce);
104 
105 /*
106  * Returns TRUE if we are "backed up" waiting for the syncing
107  * transaction to complete; otherwise returns FALSE.
108  */
109 extern boolean_t txg_stalled(struct dsl_pool *dp);
110 
111 /* returns TRUE if someone is waiting for the next txg to sync */
112 extern boolean_t txg_sync_waiting(struct dsl_pool *dp);
113 
114 extern void txg_verify(spa_t *spa, uint64_t txg);
115 
116 /*
117  * Wait for pending commit callbacks of already-synced transactions to finish
118  * processing.
119  */
120 extern void txg_wait_callbacks(struct dsl_pool *dp);
121 
122 /*
123  * Per-txg object lists.
124  */
125 
126 #define	TXG_CLEAN(txg)	((txg) - 1)
127 
128 extern void txg_list_create(txg_list_t *tl, spa_t *spa, size_t offset);
129 extern void txg_list_destroy(txg_list_t *tl);
130 extern boolean_t txg_list_empty(txg_list_t *tl, uint64_t txg);
131 extern boolean_t txg_all_lists_empty(txg_list_t *tl);
132 extern boolean_t txg_list_add(txg_list_t *tl, void *p, uint64_t txg);
133 extern boolean_t txg_list_add_tail(txg_list_t *tl, void *p, uint64_t txg);
134 extern void *txg_list_remove(txg_list_t *tl, uint64_t txg);
135 extern void *txg_list_remove_this(txg_list_t *tl, void *p, uint64_t txg);
136 extern boolean_t txg_list_member(txg_list_t *tl, void *p, uint64_t txg);
137 extern void *txg_list_head(txg_list_t *tl, uint64_t txg);
138 extern void *txg_list_next(txg_list_t *tl, void *p, uint64_t txg);
139 
140 /* Global tuning */
141 extern int zfs_txg_timeout;
142 
143 
144 #ifdef ZFS_DEBUG
145 #define	TXG_VERIFY(spa, txg)		txg_verify(spa, txg)
146 #else
147 #define	TXG_VERIFY(spa, txg)
148 #endif
149 
150 #ifdef	__cplusplus
151 }
152 #endif
153 
154 #endif	/* _SYS_TXG_H */
155