include/sys/txg.h

   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, 2014 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         txg_node_t      *tl_head[TXG_SIZE];
  64 } txg_list_t;
  65
  66 struct dsl_pool;
  67
  68 extern void txg_init(struct dsl_pool *dp, uint64_t txg);
  69 extern void txg_fini(struct dsl_pool *dp);
  70 extern void txg_sync_start(struct dsl_pool *dp);
  71 extern void txg_sync_stop(struct dsl_pool *dp);
  72 extern uint64_t txg_hold_open(struct dsl_pool *dp, txg_handle_t *txghp);
  73 extern void txg_rele_to_quiesce(txg_handle_t *txghp);
  74 extern void txg_rele_to_sync(txg_handle_t *txghp);
  75 extern void txg_register_callbacks(txg_handle_t *txghp, list_t *tx_callbacks);
  76
  77 extern void txg_delay(struct dsl_pool *dp, uint64_t txg, hrtime_t delta,
  78     hrtime_t resolution);
  79 extern void txg_kick(struct dsl_pool *dp);
  80
  81 /*
  82  * Wait until the given transaction group has finished syncing.
  83  * Try to make this happen as soon as possible (eg. kick off any
  84  * necessary syncs immediately).  If txg==0, wait for the currently open
  85  * txg to finish syncing.
  86  */
  87 extern void txg_wait_synced(struct dsl_pool *dp, uint64_t txg);
  88
  89 /*
  90  * Wait until the given transaction group, or one after it, is
  91  * the open transaction group.  Try to make this happen as soon
  92  * as possible (eg. kick off any necessary syncs immediately).
  93  * If txg == 0, wait for the next open txg.
  94  */
  95 extern void txg_wait_open(struct dsl_pool *dp, uint64_t txg);
  96
  97 /*
  98  * Returns TRUE if we are "backed up" waiting for the syncing
  99  * transaction to complete; otherwise returns FALSE.
 100  */
 101 extern boolean_t txg_stalled(struct dsl_pool *dp);
 102
 103 /* returns TRUE if someone is waiting for the next txg to sync */
 104 extern boolean_t txg_sync_waiting(struct dsl_pool *dp);
 105
 106 /*
 107  * Wait for pending commit callbacks of already-synced transactions to finish
 108  * processing.
 109  */
 110 extern void txg_wait_callbacks(struct dsl_pool *dp);
 111
 112 /*
 113  * Per-txg object lists.
 114  */
 115
 116 #define TXG_CLEAN(txg)  ((txg) - 1)
 117
 118 extern void txg_list_create(txg_list_t *tl, size_t offset);
 119 extern void txg_list_destroy(txg_list_t *tl);
 120 extern boolean_t txg_list_empty(txg_list_t *tl, uint64_t txg);
 121 extern boolean_t txg_all_lists_empty(txg_list_t *tl);
 122 extern boolean_t txg_list_add(txg_list_t *tl, void *p, uint64_t txg);
 123 extern boolean_t 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 boolean_t 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 /* Global tuning */
 131 extern int zfs_txg_timeout;
 132
 133 #ifdef  __cplusplus
 134 }
 135 #endif
 136
 137 #endif  /* _SYS_TXG_H */