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 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 #define TXG_WAIT 1ULL 49 #define TXG_NOWAIT 2ULL 50 51 typedef struct tx_cpu tx_cpu_t; 52 53 typedef struct txg_handle { 54 tx_cpu_t *th_cpu; 55 uint64_t th_txg; 56 } txg_handle_t; 57 58 typedef struct txg_node { 59 struct txg_node *tn_next[TXG_SIZE]; 60 uint8_t tn_member[TXG_SIZE]; 61 } txg_node_t; 62 63 typedef struct txg_list { 64 kmutex_t tl_lock; 65 size_t tl_offset; 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 /* 81 * Delay the caller by the specified number of ticks or until 82 * the txg closes (whichever comes first). This is intended 83 * to be used to throttle writers when the system nears its 84 * capacity. 85 */ 86 extern void txg_delay(struct dsl_pool *dp, uint64_t txg, int ticks); 87 88 /* 89 * Wait until the given transaction group has finished syncing. 90 * Try to make this happen as soon as possible (eg. kick off any 91 * necessary syncs immediately). If txg==0, wait for the currently open 92 * txg to finish syncing. 93 */ 94 extern void txg_wait_synced(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). 100 * If txg == 0, wait for the next open txg. 101 */ 102 extern void txg_wait_open(struct dsl_pool *dp, uint64_t txg); 103 104 /* 105 * Returns TRUE if we are "backed up" waiting for the syncing 106 * transaction to complete; otherwise returns FALSE. 107 */ 108 extern boolean_t txg_stalled(struct dsl_pool *dp); 109 110 /* returns TRUE if someone is waiting for the next txg to sync */ 111 extern boolean_t txg_sync_waiting(struct dsl_pool *dp); 112 113 /* 114 * Per-txg object lists. 115 */ 116 117 #define TXG_CLEAN(txg) ((txg) - 1) 118 119 extern void txg_list_create(txg_list_t *tl, size_t offset); 120 extern void txg_list_destroy(txg_list_t *tl); 121 extern boolean_t txg_list_empty(txg_list_t *tl, uint64_t txg); 122 extern int txg_list_add(txg_list_t *tl, void *p, uint64_t txg); 123 extern int txg_list_add_tail(txg_list_t *tl, void *p, uint64_t txg); 124 extern void *txg_list_remove(txg_list_t *tl, uint64_t txg); 125 extern void *txg_list_remove_this(txg_list_t *tl, void *p, uint64_t txg); 126 extern int txg_list_member(txg_list_t *tl, void *p, uint64_t txg); 127 extern void *txg_list_head(txg_list_t *tl, uint64_t txg); 128 extern void *txg_list_next(txg_list_t *tl, void *p, uint64_t txg); 129 130 #ifdef __cplusplus 131 } 132 #endif 133 134 #endif /* _SYS_TXG_H */ 135