3696 lines
111 KiB
C
3696 lines
111 KiB
C
/*
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* CDDL HEADER START
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*
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* The contents of this file are subject to the terms of the
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* Common Development and Distribution License (the "License").
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* You may not use this file except in compliance with the License.
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*
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* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
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* or http://www.opensolaris.org/os/licensing.
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* See the License for the specific language governing permissions
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* and limitations under the License.
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*
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* When distributing Covered Code, include this CDDL HEADER in each
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* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
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* If applicable, add the following below this CDDL HEADER, with the
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* fields enclosed by brackets "[]" replaced with your own identifying
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* information: Portions Copyright [yyyy] [name of copyright owner]
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*
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* CDDL HEADER END
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*/
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/*
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* Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
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* Copyright (c) 2011, 2018 by Delphix. All rights reserved.
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* Copyright (c) 2014 Integros [integros.com]
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* Copyright (c) 2018 Datto Inc.
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*/
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/* Portions Copyright 2010 Robert Milkowski */
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#include <sys/zfs_context.h>
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#include <sys/spa.h>
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#include <sys/spa_impl.h>
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#include <sys/dmu.h>
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#include <sys/zap.h>
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#include <sys/arc.h>
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#include <sys/stat.h>
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#include <sys/zil.h>
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#include <sys/zil_impl.h>
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#include <sys/dsl_dataset.h>
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#include <sys/vdev_impl.h>
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#include <sys/dmu_tx.h>
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#include <sys/dsl_pool.h>
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#include <sys/metaslab.h>
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#include <sys/trace_zfs.h>
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#include <sys/abd.h>
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/*
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* The ZFS Intent Log (ZIL) saves "transaction records" (itxs) of system
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* calls that change the file system. Each itx has enough information to
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* be able to replay them after a system crash, power loss, or
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* equivalent failure mode. These are stored in memory until either:
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*
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* 1. they are committed to the pool by the DMU transaction group
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* (txg), at which point they can be discarded; or
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* 2. they are committed to the on-disk ZIL for the dataset being
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* modified (e.g. due to an fsync, O_DSYNC, or other synchronous
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* requirement).
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*
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* In the event of a crash or power loss, the itxs contained by each
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* dataset's on-disk ZIL will be replayed when that dataset is first
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* instantiated (e.g. if the dataset is a normal filesystem, when it is
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* first mounted).
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*
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* As hinted at above, there is one ZIL per dataset (both the in-memory
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* representation, and the on-disk representation). The on-disk format
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* consists of 3 parts:
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*
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* - a single, per-dataset, ZIL header; which points to a chain of
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* - zero or more ZIL blocks; each of which contains
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* - zero or more ZIL records
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*
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* A ZIL record holds the information necessary to replay a single
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* system call transaction. A ZIL block can hold many ZIL records, and
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* the blocks are chained together, similarly to a singly linked list.
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*
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* Each ZIL block contains a block pointer (blkptr_t) to the next ZIL
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* block in the chain, and the ZIL header points to the first block in
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* the chain.
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*
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* Note, there is not a fixed place in the pool to hold these ZIL
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* blocks; they are dynamically allocated and freed as needed from the
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* blocks available on the pool, though they can be preferentially
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* allocated from a dedicated "log" vdev.
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*/
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/*
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* This controls the amount of time that a ZIL block (lwb) will remain
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* "open" when it isn't "full", and it has a thread waiting for it to be
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* committed to stable storage. Please refer to the zil_commit_waiter()
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* function (and the comments within it) for more details.
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*/
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int zfs_commit_timeout_pct = 5;
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/*
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* See zil.h for more information about these fields.
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*/
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zil_stats_t zil_stats = {
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{ "zil_commit_count", KSTAT_DATA_UINT64 },
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{ "zil_commit_writer_count", KSTAT_DATA_UINT64 },
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{ "zil_itx_count", KSTAT_DATA_UINT64 },
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{ "zil_itx_indirect_count", KSTAT_DATA_UINT64 },
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{ "zil_itx_indirect_bytes", KSTAT_DATA_UINT64 },
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{ "zil_itx_copied_count", KSTAT_DATA_UINT64 },
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{ "zil_itx_copied_bytes", KSTAT_DATA_UINT64 },
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{ "zil_itx_needcopy_count", KSTAT_DATA_UINT64 },
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{ "zil_itx_needcopy_bytes", KSTAT_DATA_UINT64 },
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{ "zil_itx_metaslab_normal_count", KSTAT_DATA_UINT64 },
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{ "zil_itx_metaslab_normal_bytes", KSTAT_DATA_UINT64 },
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{ "zil_itx_metaslab_slog_count", KSTAT_DATA_UINT64 },
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{ "zil_itx_metaslab_slog_bytes", KSTAT_DATA_UINT64 },
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};
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static kstat_t *zil_ksp;
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/*
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* Disable intent logging replay. This global ZIL switch affects all pools.
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*/
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int zil_replay_disable = 0;
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/*
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* Disable the DKIOCFLUSHWRITECACHE commands that are normally sent to
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* the disk(s) by the ZIL after an LWB write has completed. Setting this
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* will cause ZIL corruption on power loss if a volatile out-of-order
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* write cache is enabled.
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*/
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int zil_nocacheflush = 0;
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/*
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* Limit SLOG write size per commit executed with synchronous priority.
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* Any writes above that will be executed with lower (asynchronous) priority
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* to limit potential SLOG device abuse by single active ZIL writer.
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*/
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unsigned long zil_slog_bulk = 768 * 1024;
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static kmem_cache_t *zil_lwb_cache;
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static kmem_cache_t *zil_zcw_cache;
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#define LWB_EMPTY(lwb) ((BP_GET_LSIZE(&lwb->lwb_blk) - \
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sizeof (zil_chain_t)) == (lwb->lwb_sz - lwb->lwb_nused))
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static int
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zil_bp_compare(const void *x1, const void *x2)
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{
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const dva_t *dva1 = &((zil_bp_node_t *)x1)->zn_dva;
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const dva_t *dva2 = &((zil_bp_node_t *)x2)->zn_dva;
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int cmp = TREE_CMP(DVA_GET_VDEV(dva1), DVA_GET_VDEV(dva2));
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if (likely(cmp))
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return (cmp);
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return (TREE_CMP(DVA_GET_OFFSET(dva1), DVA_GET_OFFSET(dva2)));
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}
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static void
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zil_bp_tree_init(zilog_t *zilog)
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{
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avl_create(&zilog->zl_bp_tree, zil_bp_compare,
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sizeof (zil_bp_node_t), offsetof(zil_bp_node_t, zn_node));
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}
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static void
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zil_bp_tree_fini(zilog_t *zilog)
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{
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avl_tree_t *t = &zilog->zl_bp_tree;
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zil_bp_node_t *zn;
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void *cookie = NULL;
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while ((zn = avl_destroy_nodes(t, &cookie)) != NULL)
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kmem_free(zn, sizeof (zil_bp_node_t));
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avl_destroy(t);
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}
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int
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zil_bp_tree_add(zilog_t *zilog, const blkptr_t *bp)
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{
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avl_tree_t *t = &zilog->zl_bp_tree;
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const dva_t *dva;
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zil_bp_node_t *zn;
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avl_index_t where;
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if (BP_IS_EMBEDDED(bp))
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return (0);
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dva = BP_IDENTITY(bp);
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if (avl_find(t, dva, &where) != NULL)
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return (SET_ERROR(EEXIST));
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zn = kmem_alloc(sizeof (zil_bp_node_t), KM_SLEEP);
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zn->zn_dva = *dva;
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avl_insert(t, zn, where);
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return (0);
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}
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static zil_header_t *
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zil_header_in_syncing_context(zilog_t *zilog)
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{
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return ((zil_header_t *)zilog->zl_header);
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}
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static void
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zil_init_log_chain(zilog_t *zilog, blkptr_t *bp)
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{
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zio_cksum_t *zc = &bp->blk_cksum;
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zc->zc_word[ZIL_ZC_GUID_0] = spa_get_random(-1ULL);
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zc->zc_word[ZIL_ZC_GUID_1] = spa_get_random(-1ULL);
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zc->zc_word[ZIL_ZC_OBJSET] = dmu_objset_id(zilog->zl_os);
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zc->zc_word[ZIL_ZC_SEQ] = 1ULL;
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}
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/*
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* Read a log block and make sure it's valid.
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*/
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static int
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zil_read_log_block(zilog_t *zilog, boolean_t decrypt, const blkptr_t *bp,
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blkptr_t *nbp, void *dst, char **end)
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{
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enum zio_flag zio_flags = ZIO_FLAG_CANFAIL;
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arc_flags_t aflags = ARC_FLAG_WAIT;
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arc_buf_t *abuf = NULL;
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zbookmark_phys_t zb;
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int error;
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if (zilog->zl_header->zh_claim_txg == 0)
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zio_flags |= ZIO_FLAG_SPECULATIVE | ZIO_FLAG_SCRUB;
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if (!(zilog->zl_header->zh_flags & ZIL_CLAIM_LR_SEQ_VALID))
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zio_flags |= ZIO_FLAG_SPECULATIVE;
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if (!decrypt)
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zio_flags |= ZIO_FLAG_RAW;
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SET_BOOKMARK(&zb, bp->blk_cksum.zc_word[ZIL_ZC_OBJSET],
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ZB_ZIL_OBJECT, ZB_ZIL_LEVEL, bp->blk_cksum.zc_word[ZIL_ZC_SEQ]);
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error = arc_read(NULL, zilog->zl_spa, bp, arc_getbuf_func,
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&abuf, ZIO_PRIORITY_SYNC_READ, zio_flags, &aflags, &zb);
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if (error == 0) {
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zio_cksum_t cksum = bp->blk_cksum;
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/*
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* Validate the checksummed log block.
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*
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* Sequence numbers should be... sequential. The checksum
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* verifier for the next block should be bp's checksum plus 1.
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*
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* Also check the log chain linkage and size used.
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*/
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cksum.zc_word[ZIL_ZC_SEQ]++;
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if (BP_GET_CHECKSUM(bp) == ZIO_CHECKSUM_ZILOG2) {
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zil_chain_t *zilc = abuf->b_data;
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char *lr = (char *)(zilc + 1);
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uint64_t len = zilc->zc_nused - sizeof (zil_chain_t);
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if (bcmp(&cksum, &zilc->zc_next_blk.blk_cksum,
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sizeof (cksum)) || BP_IS_HOLE(&zilc->zc_next_blk)) {
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error = SET_ERROR(ECKSUM);
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} else {
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ASSERT3U(len, <=, SPA_OLD_MAXBLOCKSIZE);
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bcopy(lr, dst, len);
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*end = (char *)dst + len;
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*nbp = zilc->zc_next_blk;
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}
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} else {
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char *lr = abuf->b_data;
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uint64_t size = BP_GET_LSIZE(bp);
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zil_chain_t *zilc = (zil_chain_t *)(lr + size) - 1;
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if (bcmp(&cksum, &zilc->zc_next_blk.blk_cksum,
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sizeof (cksum)) || BP_IS_HOLE(&zilc->zc_next_blk) ||
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(zilc->zc_nused > (size - sizeof (*zilc)))) {
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error = SET_ERROR(ECKSUM);
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} else {
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ASSERT3U(zilc->zc_nused, <=,
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SPA_OLD_MAXBLOCKSIZE);
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bcopy(lr, dst, zilc->zc_nused);
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*end = (char *)dst + zilc->zc_nused;
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*nbp = zilc->zc_next_blk;
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}
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}
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arc_buf_destroy(abuf, &abuf);
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}
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return (error);
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}
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/*
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* Read a TX_WRITE log data block.
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*/
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static int
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zil_read_log_data(zilog_t *zilog, const lr_write_t *lr, void *wbuf)
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{
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enum zio_flag zio_flags = ZIO_FLAG_CANFAIL;
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const blkptr_t *bp = &lr->lr_blkptr;
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arc_flags_t aflags = ARC_FLAG_WAIT;
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arc_buf_t *abuf = NULL;
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zbookmark_phys_t zb;
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int error;
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if (BP_IS_HOLE(bp)) {
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if (wbuf != NULL)
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bzero(wbuf, MAX(BP_GET_LSIZE(bp), lr->lr_length));
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return (0);
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}
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if (zilog->zl_header->zh_claim_txg == 0)
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zio_flags |= ZIO_FLAG_SPECULATIVE | ZIO_FLAG_SCRUB;
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/*
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* If we are not using the resulting data, we are just checking that
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* it hasn't been corrupted so we don't need to waste CPU time
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* decompressing and decrypting it.
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*/
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if (wbuf == NULL)
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zio_flags |= ZIO_FLAG_RAW;
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SET_BOOKMARK(&zb, dmu_objset_id(zilog->zl_os), lr->lr_foid,
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ZB_ZIL_LEVEL, lr->lr_offset / BP_GET_LSIZE(bp));
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error = arc_read(NULL, zilog->zl_spa, bp, arc_getbuf_func, &abuf,
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ZIO_PRIORITY_SYNC_READ, zio_flags, &aflags, &zb);
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if (error == 0) {
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if (wbuf != NULL)
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bcopy(abuf->b_data, wbuf, arc_buf_size(abuf));
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arc_buf_destroy(abuf, &abuf);
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}
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return (error);
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}
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|
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/*
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* Parse the intent log, and call parse_func for each valid record within.
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*/
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int
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zil_parse(zilog_t *zilog, zil_parse_blk_func_t *parse_blk_func,
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zil_parse_lr_func_t *parse_lr_func, void *arg, uint64_t txg,
|
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boolean_t decrypt)
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{
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const zil_header_t *zh = zilog->zl_header;
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boolean_t claimed = !!zh->zh_claim_txg;
|
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uint64_t claim_blk_seq = claimed ? zh->zh_claim_blk_seq : UINT64_MAX;
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uint64_t claim_lr_seq = claimed ? zh->zh_claim_lr_seq : UINT64_MAX;
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uint64_t max_blk_seq = 0;
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uint64_t max_lr_seq = 0;
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uint64_t blk_count = 0;
|
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uint64_t lr_count = 0;
|
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blkptr_t blk, next_blk;
|
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char *lrbuf, *lrp;
|
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int error = 0;
|
|
|
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bzero(&next_blk, sizeof (blkptr_t));
|
|
|
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/*
|
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* Old logs didn't record the maximum zh_claim_lr_seq.
|
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*/
|
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if (!(zh->zh_flags & ZIL_CLAIM_LR_SEQ_VALID))
|
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claim_lr_seq = UINT64_MAX;
|
|
|
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/*
|
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* Starting at the block pointed to by zh_log we read the log chain.
|
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* For each block in the chain we strongly check that block to
|
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* ensure its validity. We stop when an invalid block is found.
|
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* For each block pointer in the chain we call parse_blk_func().
|
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* For each record in each valid block we call parse_lr_func().
|
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* If the log has been claimed, stop if we encounter a sequence
|
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* number greater than the highest claimed sequence number.
|
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*/
|
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lrbuf = zio_buf_alloc(SPA_OLD_MAXBLOCKSIZE);
|
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zil_bp_tree_init(zilog);
|
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|
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for (blk = zh->zh_log; !BP_IS_HOLE(&blk); blk = next_blk) {
|
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uint64_t blk_seq = blk.blk_cksum.zc_word[ZIL_ZC_SEQ];
|
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int reclen;
|
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char *end = NULL;
|
|
|
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if (blk_seq > claim_blk_seq)
|
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break;
|
|
|
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error = parse_blk_func(zilog, &blk, arg, txg);
|
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if (error != 0)
|
|
break;
|
|
ASSERT3U(max_blk_seq, <, blk_seq);
|
|
max_blk_seq = blk_seq;
|
|
blk_count++;
|
|
|
|
if (max_lr_seq == claim_lr_seq && max_blk_seq == claim_blk_seq)
|
|
break;
|
|
|
|
error = zil_read_log_block(zilog, decrypt, &blk, &next_blk,
|
|
lrbuf, &end);
|
|
if (error != 0)
|
|
break;
|
|
|
|
for (lrp = lrbuf; lrp < end; lrp += reclen) {
|
|
lr_t *lr = (lr_t *)lrp;
|
|
reclen = lr->lrc_reclen;
|
|
ASSERT3U(reclen, >=, sizeof (lr_t));
|
|
if (lr->lrc_seq > claim_lr_seq)
|
|
goto done;
|
|
|
|
error = parse_lr_func(zilog, lr, arg, txg);
|
|
if (error != 0)
|
|
goto done;
|
|
ASSERT3U(max_lr_seq, <, lr->lrc_seq);
|
|
max_lr_seq = lr->lrc_seq;
|
|
lr_count++;
|
|
}
|
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}
|
|
done:
|
|
zilog->zl_parse_error = error;
|
|
zilog->zl_parse_blk_seq = max_blk_seq;
|
|
zilog->zl_parse_lr_seq = max_lr_seq;
|
|
zilog->zl_parse_blk_count = blk_count;
|
|
zilog->zl_parse_lr_count = lr_count;
|
|
|
|
ASSERT(!claimed || !(zh->zh_flags & ZIL_CLAIM_LR_SEQ_VALID) ||
|
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(max_blk_seq == claim_blk_seq && max_lr_seq == claim_lr_seq) ||
|
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(decrypt && error == EIO));
|
|
|
|
zil_bp_tree_fini(zilog);
|
|
zio_buf_free(lrbuf, SPA_OLD_MAXBLOCKSIZE);
|
|
|
|
return (error);
|
|
}
|
|
|
|
/* ARGSUSED */
|
|
static int
|
|
zil_clear_log_block(zilog_t *zilog, const blkptr_t *bp, void *tx,
|
|
uint64_t first_txg)
|
|
{
|
|
ASSERT(!BP_IS_HOLE(bp));
|
|
|
|
/*
|
|
* As we call this function from the context of a rewind to a
|
|
* checkpoint, each ZIL block whose txg is later than the txg
|
|
* that we rewind to is invalid. Thus, we return -1 so
|
|
* zil_parse() doesn't attempt to read it.
|
|
*/
|
|
if (bp->blk_birth >= first_txg)
|
|
return (-1);
|
|
|
|
if (zil_bp_tree_add(zilog, bp) != 0)
|
|
return (0);
|
|
|
|
zio_free(zilog->zl_spa, first_txg, bp);
|
|
return (0);
|
|
}
|
|
|
|
/* ARGSUSED */
|
|
static int
|
|
zil_noop_log_record(zilog_t *zilog, const lr_t *lrc, void *tx,
|
|
uint64_t first_txg)
|
|
{
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
zil_claim_log_block(zilog_t *zilog, const blkptr_t *bp, void *tx,
|
|
uint64_t first_txg)
|
|
{
|
|
/*
|
|
* Claim log block if not already committed and not already claimed.
|
|
* If tx == NULL, just verify that the block is claimable.
|
|
*/
|
|
if (BP_IS_HOLE(bp) || bp->blk_birth < first_txg ||
|
|
zil_bp_tree_add(zilog, bp) != 0)
|
|
return (0);
|
|
|
|
return (zio_wait(zio_claim(NULL, zilog->zl_spa,
|
|
tx == NULL ? 0 : first_txg, bp, spa_claim_notify, NULL,
|
|
ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE | ZIO_FLAG_SCRUB)));
|
|
}
|
|
|
|
static int
|
|
zil_claim_log_record(zilog_t *zilog, const lr_t *lrc, void *tx,
|
|
uint64_t first_txg)
|
|
{
|
|
lr_write_t *lr = (lr_write_t *)lrc;
|
|
int error;
|
|
|
|
if (lrc->lrc_txtype != TX_WRITE)
|
|
return (0);
|
|
|
|
/*
|
|
* If the block is not readable, don't claim it. This can happen
|
|
* in normal operation when a log block is written to disk before
|
|
* some of the dmu_sync() blocks it points to. In this case, the
|
|
* transaction cannot have been committed to anyone (we would have
|
|
* waited for all writes to be stable first), so it is semantically
|
|
* correct to declare this the end of the log.
|
|
*/
|
|
if (lr->lr_blkptr.blk_birth >= first_txg) {
|
|
error = zil_read_log_data(zilog, lr, NULL);
|
|
if (error != 0)
|
|
return (error);
|
|
}
|
|
|
|
return (zil_claim_log_block(zilog, &lr->lr_blkptr, tx, first_txg));
|
|
}
|
|
|
|
/* ARGSUSED */
|
|
static int
|
|
zil_free_log_block(zilog_t *zilog, const blkptr_t *bp, void *tx,
|
|
uint64_t claim_txg)
|
|
{
|
|
zio_free(zilog->zl_spa, dmu_tx_get_txg(tx), bp);
|
|
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
zil_free_log_record(zilog_t *zilog, const lr_t *lrc, void *tx,
|
|
uint64_t claim_txg)
|
|
{
|
|
lr_write_t *lr = (lr_write_t *)lrc;
|
|
blkptr_t *bp = &lr->lr_blkptr;
|
|
|
|
/*
|
|
* If we previously claimed it, we need to free it.
|
|
*/
|
|
if (claim_txg != 0 && lrc->lrc_txtype == TX_WRITE &&
|
|
bp->blk_birth >= claim_txg && zil_bp_tree_add(zilog, bp) == 0 &&
|
|
!BP_IS_HOLE(bp))
|
|
zio_free(zilog->zl_spa, dmu_tx_get_txg(tx), bp);
|
|
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
zil_lwb_vdev_compare(const void *x1, const void *x2)
|
|
{
|
|
const uint64_t v1 = ((zil_vdev_node_t *)x1)->zv_vdev;
|
|
const uint64_t v2 = ((zil_vdev_node_t *)x2)->zv_vdev;
|
|
|
|
return (TREE_CMP(v1, v2));
|
|
}
|
|
|
|
static lwb_t *
|
|
zil_alloc_lwb(zilog_t *zilog, blkptr_t *bp, boolean_t slog, uint64_t txg,
|
|
boolean_t fastwrite)
|
|
{
|
|
lwb_t *lwb;
|
|
|
|
lwb = kmem_cache_alloc(zil_lwb_cache, KM_SLEEP);
|
|
lwb->lwb_zilog = zilog;
|
|
lwb->lwb_blk = *bp;
|
|
lwb->lwb_fastwrite = fastwrite;
|
|
lwb->lwb_slog = slog;
|
|
lwb->lwb_state = LWB_STATE_CLOSED;
|
|
lwb->lwb_buf = zio_buf_alloc(BP_GET_LSIZE(bp));
|
|
lwb->lwb_max_txg = txg;
|
|
lwb->lwb_write_zio = NULL;
|
|
lwb->lwb_root_zio = NULL;
|
|
lwb->lwb_tx = NULL;
|
|
lwb->lwb_issued_timestamp = 0;
|
|
if (BP_GET_CHECKSUM(bp) == ZIO_CHECKSUM_ZILOG2) {
|
|
lwb->lwb_nused = sizeof (zil_chain_t);
|
|
lwb->lwb_sz = BP_GET_LSIZE(bp);
|
|
} else {
|
|
lwb->lwb_nused = 0;
|
|
lwb->lwb_sz = BP_GET_LSIZE(bp) - sizeof (zil_chain_t);
|
|
}
|
|
|
|
mutex_enter(&zilog->zl_lock);
|
|
list_insert_tail(&zilog->zl_lwb_list, lwb);
|
|
mutex_exit(&zilog->zl_lock);
|
|
|
|
ASSERT(!MUTEX_HELD(&lwb->lwb_vdev_lock));
|
|
ASSERT(avl_is_empty(&lwb->lwb_vdev_tree));
|
|
VERIFY(list_is_empty(&lwb->lwb_waiters));
|
|
VERIFY(list_is_empty(&lwb->lwb_itxs));
|
|
|
|
return (lwb);
|
|
}
|
|
|
|
static void
|
|
zil_free_lwb(zilog_t *zilog, lwb_t *lwb)
|
|
{
|
|
ASSERT(MUTEX_HELD(&zilog->zl_lock));
|
|
ASSERT(!MUTEX_HELD(&lwb->lwb_vdev_lock));
|
|
VERIFY(list_is_empty(&lwb->lwb_waiters));
|
|
VERIFY(list_is_empty(&lwb->lwb_itxs));
|
|
ASSERT(avl_is_empty(&lwb->lwb_vdev_tree));
|
|
ASSERT3P(lwb->lwb_write_zio, ==, NULL);
|
|
ASSERT3P(lwb->lwb_root_zio, ==, NULL);
|
|
ASSERT3U(lwb->lwb_max_txg, <=, spa_syncing_txg(zilog->zl_spa));
|
|
ASSERT(lwb->lwb_state == LWB_STATE_CLOSED ||
|
|
lwb->lwb_state == LWB_STATE_FLUSH_DONE);
|
|
|
|
/*
|
|
* Clear the zilog's field to indicate this lwb is no longer
|
|
* valid, and prevent use-after-free errors.
|
|
*/
|
|
if (zilog->zl_last_lwb_opened == lwb)
|
|
zilog->zl_last_lwb_opened = NULL;
|
|
|
|
kmem_cache_free(zil_lwb_cache, lwb);
|
|
}
|
|
|
|
/*
|
|
* Called when we create in-memory log transactions so that we know
|
|
* to cleanup the itxs at the end of spa_sync().
|
|
*/
|
|
static void
|
|
zilog_dirty(zilog_t *zilog, uint64_t txg)
|
|
{
|
|
dsl_pool_t *dp = zilog->zl_dmu_pool;
|
|
dsl_dataset_t *ds = dmu_objset_ds(zilog->zl_os);
|
|
|
|
ASSERT(spa_writeable(zilog->zl_spa));
|
|
|
|
if (ds->ds_is_snapshot)
|
|
panic("dirtying snapshot!");
|
|
|
|
if (txg_list_add(&dp->dp_dirty_zilogs, zilog, txg)) {
|
|
/* up the hold count until we can be written out */
|
|
dmu_buf_add_ref(ds->ds_dbuf, zilog);
|
|
|
|
zilog->zl_dirty_max_txg = MAX(txg, zilog->zl_dirty_max_txg);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Determine if the zil is dirty in the specified txg. Callers wanting to
|
|
* ensure that the dirty state does not change must hold the itxg_lock for
|
|
* the specified txg. Holding the lock will ensure that the zil cannot be
|
|
* dirtied (zil_itx_assign) or cleaned (zil_clean) while we check its current
|
|
* state.
|
|
*/
|
|
static boolean_t __maybe_unused
|
|
zilog_is_dirty_in_txg(zilog_t *zilog, uint64_t txg)
|
|
{
|
|
dsl_pool_t *dp = zilog->zl_dmu_pool;
|
|
|
|
if (txg_list_member(&dp->dp_dirty_zilogs, zilog, txg & TXG_MASK))
|
|
return (B_TRUE);
|
|
return (B_FALSE);
|
|
}
|
|
|
|
/*
|
|
* Determine if the zil is dirty. The zil is considered dirty if it has
|
|
* any pending itx records that have not been cleaned by zil_clean().
|
|
*/
|
|
static boolean_t
|
|
zilog_is_dirty(zilog_t *zilog)
|
|
{
|
|
dsl_pool_t *dp = zilog->zl_dmu_pool;
|
|
|
|
for (int t = 0; t < TXG_SIZE; t++) {
|
|
if (txg_list_member(&dp->dp_dirty_zilogs, zilog, t))
|
|
return (B_TRUE);
|
|
}
|
|
return (B_FALSE);
|
|
}
|
|
|
|
/*
|
|
* Create an on-disk intent log.
|
|
*/
|
|
static lwb_t *
|
|
zil_create(zilog_t *zilog)
|
|
{
|
|
const zil_header_t *zh = zilog->zl_header;
|
|
lwb_t *lwb = NULL;
|
|
uint64_t txg = 0;
|
|
dmu_tx_t *tx = NULL;
|
|
blkptr_t blk;
|
|
int error = 0;
|
|
boolean_t fastwrite = FALSE;
|
|
boolean_t slog = FALSE;
|
|
|
|
/*
|
|
* Wait for any previous destroy to complete.
|
|
*/
|
|
txg_wait_synced(zilog->zl_dmu_pool, zilog->zl_destroy_txg);
|
|
|
|
ASSERT(zh->zh_claim_txg == 0);
|
|
ASSERT(zh->zh_replay_seq == 0);
|
|
|
|
blk = zh->zh_log;
|
|
|
|
/*
|
|
* Allocate an initial log block if:
|
|
* - there isn't one already
|
|
* - the existing block is the wrong endianness
|
|
*/
|
|
if (BP_IS_HOLE(&blk) || BP_SHOULD_BYTESWAP(&blk)) {
|
|
tx = dmu_tx_create(zilog->zl_os);
|
|
VERIFY0(dmu_tx_assign(tx, TXG_WAIT));
|
|
dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx);
|
|
txg = dmu_tx_get_txg(tx);
|
|
|
|
if (!BP_IS_HOLE(&blk)) {
|
|
zio_free(zilog->zl_spa, txg, &blk);
|
|
BP_ZERO(&blk);
|
|
}
|
|
|
|
error = zio_alloc_zil(zilog->zl_spa, zilog->zl_os, txg, &blk,
|
|
ZIL_MIN_BLKSZ, &slog);
|
|
fastwrite = TRUE;
|
|
|
|
if (error == 0)
|
|
zil_init_log_chain(zilog, &blk);
|
|
}
|
|
|
|
/*
|
|
* Allocate a log write block (lwb) for the first log block.
|
|
*/
|
|
if (error == 0)
|
|
lwb = zil_alloc_lwb(zilog, &blk, slog, txg, fastwrite);
|
|
|
|
/*
|
|
* If we just allocated the first log block, commit our transaction
|
|
* and wait for zil_sync() to stuff the block pointer into zh_log.
|
|
* (zh is part of the MOS, so we cannot modify it in open context.)
|
|
*/
|
|
if (tx != NULL) {
|
|
dmu_tx_commit(tx);
|
|
txg_wait_synced(zilog->zl_dmu_pool, txg);
|
|
}
|
|
|
|
ASSERT(error != 0 || bcmp(&blk, &zh->zh_log, sizeof (blk)) == 0);
|
|
IMPLY(error == 0, lwb != NULL);
|
|
|
|
return (lwb);
|
|
}
|
|
|
|
/*
|
|
* In one tx, free all log blocks and clear the log header. If keep_first
|
|
* is set, then we're replaying a log with no content. We want to keep the
|
|
* first block, however, so that the first synchronous transaction doesn't
|
|
* require a txg_wait_synced() in zil_create(). We don't need to
|
|
* txg_wait_synced() here either when keep_first is set, because both
|
|
* zil_create() and zil_destroy() will wait for any in-progress destroys
|
|
* to complete.
|
|
*/
|
|
void
|
|
zil_destroy(zilog_t *zilog, boolean_t keep_first)
|
|
{
|
|
const zil_header_t *zh = zilog->zl_header;
|
|
lwb_t *lwb;
|
|
dmu_tx_t *tx;
|
|
uint64_t txg;
|
|
|
|
/*
|
|
* Wait for any previous destroy to complete.
|
|
*/
|
|
txg_wait_synced(zilog->zl_dmu_pool, zilog->zl_destroy_txg);
|
|
|
|
zilog->zl_old_header = *zh; /* debugging aid */
|
|
|
|
if (BP_IS_HOLE(&zh->zh_log))
|
|
return;
|
|
|
|
tx = dmu_tx_create(zilog->zl_os);
|
|
VERIFY0(dmu_tx_assign(tx, TXG_WAIT));
|
|
dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx);
|
|
txg = dmu_tx_get_txg(tx);
|
|
|
|
mutex_enter(&zilog->zl_lock);
|
|
|
|
ASSERT3U(zilog->zl_destroy_txg, <, txg);
|
|
zilog->zl_destroy_txg = txg;
|
|
zilog->zl_keep_first = keep_first;
|
|
|
|
if (!list_is_empty(&zilog->zl_lwb_list)) {
|
|
ASSERT(zh->zh_claim_txg == 0);
|
|
VERIFY(!keep_first);
|
|
while ((lwb = list_head(&zilog->zl_lwb_list)) != NULL) {
|
|
if (lwb->lwb_fastwrite)
|
|
metaslab_fastwrite_unmark(zilog->zl_spa,
|
|
&lwb->lwb_blk);
|
|
|
|
list_remove(&zilog->zl_lwb_list, lwb);
|
|
if (lwb->lwb_buf != NULL)
|
|
zio_buf_free(lwb->lwb_buf, lwb->lwb_sz);
|
|
zio_free(zilog->zl_spa, txg, &lwb->lwb_blk);
|
|
zil_free_lwb(zilog, lwb);
|
|
}
|
|
} else if (!keep_first) {
|
|
zil_destroy_sync(zilog, tx);
|
|
}
|
|
mutex_exit(&zilog->zl_lock);
|
|
|
|
dmu_tx_commit(tx);
|
|
}
|
|
|
|
void
|
|
zil_destroy_sync(zilog_t *zilog, dmu_tx_t *tx)
|
|
{
|
|
ASSERT(list_is_empty(&zilog->zl_lwb_list));
|
|
(void) zil_parse(zilog, zil_free_log_block,
|
|
zil_free_log_record, tx, zilog->zl_header->zh_claim_txg, B_FALSE);
|
|
}
|
|
|
|
int
|
|
zil_claim(dsl_pool_t *dp, dsl_dataset_t *ds, void *txarg)
|
|
{
|
|
dmu_tx_t *tx = txarg;
|
|
zilog_t *zilog;
|
|
uint64_t first_txg;
|
|
zil_header_t *zh;
|
|
objset_t *os;
|
|
int error;
|
|
|
|
error = dmu_objset_own_obj(dp, ds->ds_object,
|
|
DMU_OST_ANY, B_FALSE, B_FALSE, FTAG, &os);
|
|
if (error != 0) {
|
|
/*
|
|
* EBUSY indicates that the objset is inconsistent, in which
|
|
* case it can not have a ZIL.
|
|
*/
|
|
if (error != EBUSY) {
|
|
cmn_err(CE_WARN, "can't open objset for %llu, error %u",
|
|
(unsigned long long)ds->ds_object, error);
|
|
}
|
|
|
|
return (0);
|
|
}
|
|
|
|
zilog = dmu_objset_zil(os);
|
|
zh = zil_header_in_syncing_context(zilog);
|
|
ASSERT3U(tx->tx_txg, ==, spa_first_txg(zilog->zl_spa));
|
|
first_txg = spa_min_claim_txg(zilog->zl_spa);
|
|
|
|
/*
|
|
* If the spa_log_state is not set to be cleared, check whether
|
|
* the current uberblock is a checkpoint one and if the current
|
|
* header has been claimed before moving on.
|
|
*
|
|
* If the current uberblock is a checkpointed uberblock then
|
|
* one of the following scenarios took place:
|
|
*
|
|
* 1] We are currently rewinding to the checkpoint of the pool.
|
|
* 2] We crashed in the middle of a checkpoint rewind but we
|
|
* did manage to write the checkpointed uberblock to the
|
|
* vdev labels, so when we tried to import the pool again
|
|
* the checkpointed uberblock was selected from the import
|
|
* procedure.
|
|
*
|
|
* In both cases we want to zero out all the ZIL blocks, except
|
|
* the ones that have been claimed at the time of the checkpoint
|
|
* (their zh_claim_txg != 0). The reason is that these blocks
|
|
* may be corrupted since we may have reused their locations on
|
|
* disk after we took the checkpoint.
|
|
*
|
|
* We could try to set spa_log_state to SPA_LOG_CLEAR earlier
|
|
* when we first figure out whether the current uberblock is
|
|
* checkpointed or not. Unfortunately, that would discard all
|
|
* the logs, including the ones that are claimed, and we would
|
|
* leak space.
|
|
*/
|
|
if (spa_get_log_state(zilog->zl_spa) == SPA_LOG_CLEAR ||
|
|
(zilog->zl_spa->spa_uberblock.ub_checkpoint_txg != 0 &&
|
|
zh->zh_claim_txg == 0)) {
|
|
if (!BP_IS_HOLE(&zh->zh_log)) {
|
|
(void) zil_parse(zilog, zil_clear_log_block,
|
|
zil_noop_log_record, tx, first_txg, B_FALSE);
|
|
}
|
|
BP_ZERO(&zh->zh_log);
|
|
if (os->os_encrypted)
|
|
os->os_next_write_raw[tx->tx_txg & TXG_MASK] = B_TRUE;
|
|
dsl_dataset_dirty(dmu_objset_ds(os), tx);
|
|
dmu_objset_disown(os, B_FALSE, FTAG);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* If we are not rewinding and opening the pool normally, then
|
|
* the min_claim_txg should be equal to the first txg of the pool.
|
|
*/
|
|
ASSERT3U(first_txg, ==, spa_first_txg(zilog->zl_spa));
|
|
|
|
/*
|
|
* Claim all log blocks if we haven't already done so, and remember
|
|
* the highest claimed sequence number. This ensures that if we can
|
|
* read only part of the log now (e.g. due to a missing device),
|
|
* but we can read the entire log later, we will not try to replay
|
|
* or destroy beyond the last block we successfully claimed.
|
|
*/
|
|
ASSERT3U(zh->zh_claim_txg, <=, first_txg);
|
|
if (zh->zh_claim_txg == 0 && !BP_IS_HOLE(&zh->zh_log)) {
|
|
(void) zil_parse(zilog, zil_claim_log_block,
|
|
zil_claim_log_record, tx, first_txg, B_FALSE);
|
|
zh->zh_claim_txg = first_txg;
|
|
zh->zh_claim_blk_seq = zilog->zl_parse_blk_seq;
|
|
zh->zh_claim_lr_seq = zilog->zl_parse_lr_seq;
|
|
if (zilog->zl_parse_lr_count || zilog->zl_parse_blk_count > 1)
|
|
zh->zh_flags |= ZIL_REPLAY_NEEDED;
|
|
zh->zh_flags |= ZIL_CLAIM_LR_SEQ_VALID;
|
|
if (os->os_encrypted)
|
|
os->os_next_write_raw[tx->tx_txg & TXG_MASK] = B_TRUE;
|
|
dsl_dataset_dirty(dmu_objset_ds(os), tx);
|
|
}
|
|
|
|
ASSERT3U(first_txg, ==, (spa_last_synced_txg(zilog->zl_spa) + 1));
|
|
dmu_objset_disown(os, B_FALSE, FTAG);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Check the log by walking the log chain.
|
|
* Checksum errors are ok as they indicate the end of the chain.
|
|
* Any other error (no device or read failure) returns an error.
|
|
*/
|
|
/* ARGSUSED */
|
|
int
|
|
zil_check_log_chain(dsl_pool_t *dp, dsl_dataset_t *ds, void *tx)
|
|
{
|
|
zilog_t *zilog;
|
|
objset_t *os;
|
|
blkptr_t *bp;
|
|
int error;
|
|
|
|
ASSERT(tx == NULL);
|
|
|
|
error = dmu_objset_from_ds(ds, &os);
|
|
if (error != 0) {
|
|
cmn_err(CE_WARN, "can't open objset %llu, error %d",
|
|
(unsigned long long)ds->ds_object, error);
|
|
return (0);
|
|
}
|
|
|
|
zilog = dmu_objset_zil(os);
|
|
bp = (blkptr_t *)&zilog->zl_header->zh_log;
|
|
|
|
if (!BP_IS_HOLE(bp)) {
|
|
vdev_t *vd;
|
|
boolean_t valid = B_TRUE;
|
|
|
|
/*
|
|
* Check the first block and determine if it's on a log device
|
|
* which may have been removed or faulted prior to loading this
|
|
* pool. If so, there's no point in checking the rest of the
|
|
* log as its content should have already been synced to the
|
|
* pool.
|
|
*/
|
|
spa_config_enter(os->os_spa, SCL_STATE, FTAG, RW_READER);
|
|
vd = vdev_lookup_top(os->os_spa, DVA_GET_VDEV(&bp->blk_dva[0]));
|
|
if (vd->vdev_islog && vdev_is_dead(vd))
|
|
valid = vdev_log_state_valid(vd);
|
|
spa_config_exit(os->os_spa, SCL_STATE, FTAG);
|
|
|
|
if (!valid)
|
|
return (0);
|
|
|
|
/*
|
|
* Check whether the current uberblock is checkpointed (e.g.
|
|
* we are rewinding) and whether the current header has been
|
|
* claimed or not. If it hasn't then skip verifying it. We
|
|
* do this because its ZIL blocks may be part of the pool's
|
|
* state before the rewind, which is no longer valid.
|
|
*/
|
|
zil_header_t *zh = zil_header_in_syncing_context(zilog);
|
|
if (zilog->zl_spa->spa_uberblock.ub_checkpoint_txg != 0 &&
|
|
zh->zh_claim_txg == 0)
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Because tx == NULL, zil_claim_log_block() will not actually claim
|
|
* any blocks, but just determine whether it is possible to do so.
|
|
* In addition to checking the log chain, zil_claim_log_block()
|
|
* will invoke zio_claim() with a done func of spa_claim_notify(),
|
|
* which will update spa_max_claim_txg. See spa_load() for details.
|
|
*/
|
|
error = zil_parse(zilog, zil_claim_log_block, zil_claim_log_record, tx,
|
|
zilog->zl_header->zh_claim_txg ? -1ULL :
|
|
spa_min_claim_txg(os->os_spa), B_FALSE);
|
|
|
|
return ((error == ECKSUM || error == ENOENT) ? 0 : error);
|
|
}
|
|
|
|
/*
|
|
* When an itx is "skipped", this function is used to properly mark the
|
|
* waiter as "done, and signal any thread(s) waiting on it. An itx can
|
|
* be skipped (and not committed to an lwb) for a variety of reasons,
|
|
* one of them being that the itx was committed via spa_sync(), prior to
|
|
* it being committed to an lwb; this can happen if a thread calling
|
|
* zil_commit() is racing with spa_sync().
|
|
*/
|
|
static void
|
|
zil_commit_waiter_skip(zil_commit_waiter_t *zcw)
|
|
{
|
|
mutex_enter(&zcw->zcw_lock);
|
|
ASSERT3B(zcw->zcw_done, ==, B_FALSE);
|
|
zcw->zcw_done = B_TRUE;
|
|
cv_broadcast(&zcw->zcw_cv);
|
|
mutex_exit(&zcw->zcw_lock);
|
|
}
|
|
|
|
/*
|
|
* This function is used when the given waiter is to be linked into an
|
|
* lwb's "lwb_waiter" list; i.e. when the itx is committed to the lwb.
|
|
* At this point, the waiter will no longer be referenced by the itx,
|
|
* and instead, will be referenced by the lwb.
|
|
*/
|
|
static void
|
|
zil_commit_waiter_link_lwb(zil_commit_waiter_t *zcw, lwb_t *lwb)
|
|
{
|
|
/*
|
|
* The lwb_waiters field of the lwb is protected by the zilog's
|
|
* zl_lock, thus it must be held when calling this function.
|
|
*/
|
|
ASSERT(MUTEX_HELD(&lwb->lwb_zilog->zl_lock));
|
|
|
|
mutex_enter(&zcw->zcw_lock);
|
|
ASSERT(!list_link_active(&zcw->zcw_node));
|
|
ASSERT3P(zcw->zcw_lwb, ==, NULL);
|
|
ASSERT3P(lwb, !=, NULL);
|
|
ASSERT(lwb->lwb_state == LWB_STATE_OPENED ||
|
|
lwb->lwb_state == LWB_STATE_ISSUED ||
|
|
lwb->lwb_state == LWB_STATE_WRITE_DONE);
|
|
|
|
list_insert_tail(&lwb->lwb_waiters, zcw);
|
|
zcw->zcw_lwb = lwb;
|
|
mutex_exit(&zcw->zcw_lock);
|
|
}
|
|
|
|
/*
|
|
* This function is used when zio_alloc_zil() fails to allocate a ZIL
|
|
* block, and the given waiter must be linked to the "nolwb waiters"
|
|
* list inside of zil_process_commit_list().
|
|
*/
|
|
static void
|
|
zil_commit_waiter_link_nolwb(zil_commit_waiter_t *zcw, list_t *nolwb)
|
|
{
|
|
mutex_enter(&zcw->zcw_lock);
|
|
ASSERT(!list_link_active(&zcw->zcw_node));
|
|
ASSERT3P(zcw->zcw_lwb, ==, NULL);
|
|
list_insert_tail(nolwb, zcw);
|
|
mutex_exit(&zcw->zcw_lock);
|
|
}
|
|
|
|
void
|
|
zil_lwb_add_block(lwb_t *lwb, const blkptr_t *bp)
|
|
{
|
|
avl_tree_t *t = &lwb->lwb_vdev_tree;
|
|
avl_index_t where;
|
|
zil_vdev_node_t *zv, zvsearch;
|
|
int ndvas = BP_GET_NDVAS(bp);
|
|
int i;
|
|
|
|
if (zil_nocacheflush)
|
|
return;
|
|
|
|
mutex_enter(&lwb->lwb_vdev_lock);
|
|
for (i = 0; i < ndvas; i++) {
|
|
zvsearch.zv_vdev = DVA_GET_VDEV(&bp->blk_dva[i]);
|
|
if (avl_find(t, &zvsearch, &where) == NULL) {
|
|
zv = kmem_alloc(sizeof (*zv), KM_SLEEP);
|
|
zv->zv_vdev = zvsearch.zv_vdev;
|
|
avl_insert(t, zv, where);
|
|
}
|
|
}
|
|
mutex_exit(&lwb->lwb_vdev_lock);
|
|
}
|
|
|
|
static void
|
|
zil_lwb_flush_defer(lwb_t *lwb, lwb_t *nlwb)
|
|
{
|
|
avl_tree_t *src = &lwb->lwb_vdev_tree;
|
|
avl_tree_t *dst = &nlwb->lwb_vdev_tree;
|
|
void *cookie = NULL;
|
|
zil_vdev_node_t *zv;
|
|
|
|
ASSERT3S(lwb->lwb_state, ==, LWB_STATE_WRITE_DONE);
|
|
ASSERT3S(nlwb->lwb_state, !=, LWB_STATE_WRITE_DONE);
|
|
ASSERT3S(nlwb->lwb_state, !=, LWB_STATE_FLUSH_DONE);
|
|
|
|
/*
|
|
* While 'lwb' is at a point in its lifetime where lwb_vdev_tree does
|
|
* not need the protection of lwb_vdev_lock (it will only be modified
|
|
* while holding zilog->zl_lock) as its writes and those of its
|
|
* children have all completed. The younger 'nlwb' may be waiting on
|
|
* future writes to additional vdevs.
|
|
*/
|
|
mutex_enter(&nlwb->lwb_vdev_lock);
|
|
/*
|
|
* Tear down the 'lwb' vdev tree, ensuring that entries which do not
|
|
* exist in 'nlwb' are moved to it, freeing any would-be duplicates.
|
|
*/
|
|
while ((zv = avl_destroy_nodes(src, &cookie)) != NULL) {
|
|
avl_index_t where;
|
|
|
|
if (avl_find(dst, zv, &where) == NULL) {
|
|
avl_insert(dst, zv, where);
|
|
} else {
|
|
kmem_free(zv, sizeof (*zv));
|
|
}
|
|
}
|
|
mutex_exit(&nlwb->lwb_vdev_lock);
|
|
}
|
|
|
|
void
|
|
zil_lwb_add_txg(lwb_t *lwb, uint64_t txg)
|
|
{
|
|
lwb->lwb_max_txg = MAX(lwb->lwb_max_txg, txg);
|
|
}
|
|
|
|
/*
|
|
* This function is a called after all vdevs associated with a given lwb
|
|
* write have completed their DKIOCFLUSHWRITECACHE command; or as soon
|
|
* as the lwb write completes, if "zil_nocacheflush" is set. Further,
|
|
* all "previous" lwb's will have completed before this function is
|
|
* called; i.e. this function is called for all previous lwbs before
|
|
* it's called for "this" lwb (enforced via zio the dependencies
|
|
* configured in zil_lwb_set_zio_dependency()).
|
|
*
|
|
* The intention is for this function to be called as soon as the
|
|
* contents of an lwb are considered "stable" on disk, and will survive
|
|
* any sudden loss of power. At this point, any threads waiting for the
|
|
* lwb to reach this state are signalled, and the "waiter" structures
|
|
* are marked "done".
|
|
*/
|
|
static void
|
|
zil_lwb_flush_vdevs_done(zio_t *zio)
|
|
{
|
|
lwb_t *lwb = zio->io_private;
|
|
zilog_t *zilog = lwb->lwb_zilog;
|
|
dmu_tx_t *tx = lwb->lwb_tx;
|
|
zil_commit_waiter_t *zcw;
|
|
itx_t *itx;
|
|
|
|
spa_config_exit(zilog->zl_spa, SCL_STATE, lwb);
|
|
|
|
zio_buf_free(lwb->lwb_buf, lwb->lwb_sz);
|
|
|
|
mutex_enter(&zilog->zl_lock);
|
|
|
|
/*
|
|
* Ensure the lwb buffer pointer is cleared before releasing the
|
|
* txg. If we have had an allocation failure and the txg is
|
|
* waiting to sync then we want zil_sync() to remove the lwb so
|
|
* that it's not picked up as the next new one in
|
|
* zil_process_commit_list(). zil_sync() will only remove the
|
|
* lwb if lwb_buf is null.
|
|
*/
|
|
lwb->lwb_buf = NULL;
|
|
lwb->lwb_tx = NULL;
|
|
|
|
ASSERT3U(lwb->lwb_issued_timestamp, >, 0);
|
|
zilog->zl_last_lwb_latency = gethrtime() - lwb->lwb_issued_timestamp;
|
|
|
|
lwb->lwb_root_zio = NULL;
|
|
|
|
ASSERT3S(lwb->lwb_state, ==, LWB_STATE_WRITE_DONE);
|
|
lwb->lwb_state = LWB_STATE_FLUSH_DONE;
|
|
|
|
if (zilog->zl_last_lwb_opened == lwb) {
|
|
/*
|
|
* Remember the highest committed log sequence number
|
|
* for ztest. We only update this value when all the log
|
|
* writes succeeded, because ztest wants to ASSERT that
|
|
* it got the whole log chain.
|
|
*/
|
|
zilog->zl_commit_lr_seq = zilog->zl_lr_seq;
|
|
}
|
|
|
|
while ((itx = list_head(&lwb->lwb_itxs)) != NULL) {
|
|
list_remove(&lwb->lwb_itxs, itx);
|
|
zil_itx_destroy(itx);
|
|
}
|
|
|
|
while ((zcw = list_head(&lwb->lwb_waiters)) != NULL) {
|
|
mutex_enter(&zcw->zcw_lock);
|
|
|
|
ASSERT(list_link_active(&zcw->zcw_node));
|
|
list_remove(&lwb->lwb_waiters, zcw);
|
|
|
|
ASSERT3P(zcw->zcw_lwb, ==, lwb);
|
|
zcw->zcw_lwb = NULL;
|
|
|
|
zcw->zcw_zio_error = zio->io_error;
|
|
|
|
ASSERT3B(zcw->zcw_done, ==, B_FALSE);
|
|
zcw->zcw_done = B_TRUE;
|
|
cv_broadcast(&zcw->zcw_cv);
|
|
|
|
mutex_exit(&zcw->zcw_lock);
|
|
}
|
|
|
|
mutex_exit(&zilog->zl_lock);
|
|
|
|
/*
|
|
* Now that we've written this log block, we have a stable pointer
|
|
* to the next block in the chain, so it's OK to let the txg in
|
|
* which we allocated the next block sync.
|
|
*/
|
|
dmu_tx_commit(tx);
|
|
}
|
|
|
|
/*
|
|
* This is called when an lwb's write zio completes. The callback's
|
|
* purpose is to issue the DKIOCFLUSHWRITECACHE commands for the vdevs
|
|
* in the lwb's lwb_vdev_tree. The tree will contain the vdevs involved
|
|
* in writing out this specific lwb's data, and in the case that cache
|
|
* flushes have been deferred, vdevs involved in writing the data for
|
|
* previous lwbs. The writes corresponding to all the vdevs in the
|
|
* lwb_vdev_tree will have completed by the time this is called, due to
|
|
* the zio dependencies configured in zil_lwb_set_zio_dependency(),
|
|
* which takes deferred flushes into account. The lwb will be "done"
|
|
* once zil_lwb_flush_vdevs_done() is called, which occurs in the zio
|
|
* completion callback for the lwb's root zio.
|
|
*/
|
|
static void
|
|
zil_lwb_write_done(zio_t *zio)
|
|
{
|
|
lwb_t *lwb = zio->io_private;
|
|
spa_t *spa = zio->io_spa;
|
|
zilog_t *zilog = lwb->lwb_zilog;
|
|
avl_tree_t *t = &lwb->lwb_vdev_tree;
|
|
void *cookie = NULL;
|
|
zil_vdev_node_t *zv;
|
|
lwb_t *nlwb;
|
|
|
|
ASSERT3S(spa_config_held(spa, SCL_STATE, RW_READER), !=, 0);
|
|
|
|
ASSERT(BP_GET_COMPRESS(zio->io_bp) == ZIO_COMPRESS_OFF);
|
|
ASSERT(BP_GET_TYPE(zio->io_bp) == DMU_OT_INTENT_LOG);
|
|
ASSERT(BP_GET_LEVEL(zio->io_bp) == 0);
|
|
ASSERT(BP_GET_BYTEORDER(zio->io_bp) == ZFS_HOST_BYTEORDER);
|
|
ASSERT(!BP_IS_GANG(zio->io_bp));
|
|
ASSERT(!BP_IS_HOLE(zio->io_bp));
|
|
ASSERT(BP_GET_FILL(zio->io_bp) == 0);
|
|
|
|
abd_put(zio->io_abd);
|
|
|
|
mutex_enter(&zilog->zl_lock);
|
|
ASSERT3S(lwb->lwb_state, ==, LWB_STATE_ISSUED);
|
|
lwb->lwb_state = LWB_STATE_WRITE_DONE;
|
|
lwb->lwb_write_zio = NULL;
|
|
lwb->lwb_fastwrite = FALSE;
|
|
nlwb = list_next(&zilog->zl_lwb_list, lwb);
|
|
mutex_exit(&zilog->zl_lock);
|
|
|
|
if (avl_numnodes(t) == 0)
|
|
return;
|
|
|
|
/*
|
|
* If there was an IO error, we're not going to call zio_flush()
|
|
* on these vdevs, so we simply empty the tree and free the
|
|
* nodes. We avoid calling zio_flush() since there isn't any
|
|
* good reason for doing so, after the lwb block failed to be
|
|
* written out.
|
|
*/
|
|
if (zio->io_error != 0) {
|
|
while ((zv = avl_destroy_nodes(t, &cookie)) != NULL)
|
|
kmem_free(zv, sizeof (*zv));
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* If this lwb does not have any threads waiting for it to
|
|
* complete, we want to defer issuing the DKIOCFLUSHWRITECACHE
|
|
* command to the vdevs written to by "this" lwb, and instead
|
|
* rely on the "next" lwb to handle the DKIOCFLUSHWRITECACHE
|
|
* command for those vdevs. Thus, we merge the vdev tree of
|
|
* "this" lwb with the vdev tree of the "next" lwb in the list,
|
|
* and assume the "next" lwb will handle flushing the vdevs (or
|
|
* deferring the flush(s) again).
|
|
*
|
|
* This is a useful performance optimization, especially for
|
|
* workloads with lots of async write activity and few sync
|
|
* write and/or fsync activity, as it has the potential to
|
|
* coalesce multiple flush commands to a vdev into one.
|
|
*/
|
|
if (list_head(&lwb->lwb_waiters) == NULL && nlwb != NULL) {
|
|
zil_lwb_flush_defer(lwb, nlwb);
|
|
ASSERT(avl_is_empty(&lwb->lwb_vdev_tree));
|
|
return;
|
|
}
|
|
|
|
while ((zv = avl_destroy_nodes(t, &cookie)) != NULL) {
|
|
vdev_t *vd = vdev_lookup_top(spa, zv->zv_vdev);
|
|
if (vd != NULL)
|
|
zio_flush(lwb->lwb_root_zio, vd);
|
|
kmem_free(zv, sizeof (*zv));
|
|
}
|
|
}
|
|
|
|
static void
|
|
zil_lwb_set_zio_dependency(zilog_t *zilog, lwb_t *lwb)
|
|
{
|
|
lwb_t *last_lwb_opened = zilog->zl_last_lwb_opened;
|
|
|
|
ASSERT(MUTEX_HELD(&zilog->zl_issuer_lock));
|
|
ASSERT(MUTEX_HELD(&zilog->zl_lock));
|
|
|
|
/*
|
|
* The zilog's "zl_last_lwb_opened" field is used to build the
|
|
* lwb/zio dependency chain, which is used to preserve the
|
|
* ordering of lwb completions that is required by the semantics
|
|
* of the ZIL. Each new lwb zio becomes a parent of the
|
|
* "previous" lwb zio, such that the new lwb's zio cannot
|
|
* complete until the "previous" lwb's zio completes.
|
|
*
|
|
* This is required by the semantics of zil_commit(); the commit
|
|
* waiters attached to the lwbs will be woken in the lwb zio's
|
|
* completion callback, so this zio dependency graph ensures the
|
|
* waiters are woken in the correct order (the same order the
|
|
* lwbs were created).
|
|
*/
|
|
if (last_lwb_opened != NULL &&
|
|
last_lwb_opened->lwb_state != LWB_STATE_FLUSH_DONE) {
|
|
ASSERT(last_lwb_opened->lwb_state == LWB_STATE_OPENED ||
|
|
last_lwb_opened->lwb_state == LWB_STATE_ISSUED ||
|
|
last_lwb_opened->lwb_state == LWB_STATE_WRITE_DONE);
|
|
|
|
ASSERT3P(last_lwb_opened->lwb_root_zio, !=, NULL);
|
|
zio_add_child(lwb->lwb_root_zio,
|
|
last_lwb_opened->lwb_root_zio);
|
|
|
|
/*
|
|
* If the previous lwb's write hasn't already completed,
|
|
* we also want to order the completion of the lwb write
|
|
* zios (above, we only order the completion of the lwb
|
|
* root zios). This is required because of how we can
|
|
* defer the DKIOCFLUSHWRITECACHE commands for each lwb.
|
|
*
|
|
* When the DKIOCFLUSHWRITECACHE commands are deferred,
|
|
* the previous lwb will rely on this lwb to flush the
|
|
* vdevs written to by that previous lwb. Thus, we need
|
|
* to ensure this lwb doesn't issue the flush until
|
|
* after the previous lwb's write completes. We ensure
|
|
* this ordering by setting the zio parent/child
|
|
* relationship here.
|
|
*
|
|
* Without this relationship on the lwb's write zio,
|
|
* it's possible for this lwb's write to complete prior
|
|
* to the previous lwb's write completing; and thus, the
|
|
* vdevs for the previous lwb would be flushed prior to
|
|
* that lwb's data being written to those vdevs (the
|
|
* vdevs are flushed in the lwb write zio's completion
|
|
* handler, zil_lwb_write_done()).
|
|
*/
|
|
if (last_lwb_opened->lwb_state != LWB_STATE_WRITE_DONE) {
|
|
ASSERT(last_lwb_opened->lwb_state == LWB_STATE_OPENED ||
|
|
last_lwb_opened->lwb_state == LWB_STATE_ISSUED);
|
|
|
|
ASSERT3P(last_lwb_opened->lwb_write_zio, !=, NULL);
|
|
zio_add_child(lwb->lwb_write_zio,
|
|
last_lwb_opened->lwb_write_zio);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* This function's purpose is to "open" an lwb such that it is ready to
|
|
* accept new itxs being committed to it. To do this, the lwb's zio
|
|
* structures are created, and linked to the lwb. This function is
|
|
* idempotent; if the passed in lwb has already been opened, this
|
|
* function is essentially a no-op.
|
|
*/
|
|
static void
|
|
zil_lwb_write_open(zilog_t *zilog, lwb_t *lwb)
|
|
{
|
|
zbookmark_phys_t zb;
|
|
zio_priority_t prio;
|
|
|
|
ASSERT(MUTEX_HELD(&zilog->zl_issuer_lock));
|
|
ASSERT3P(lwb, !=, NULL);
|
|
EQUIV(lwb->lwb_root_zio == NULL, lwb->lwb_state == LWB_STATE_CLOSED);
|
|
EQUIV(lwb->lwb_root_zio != NULL, lwb->lwb_state == LWB_STATE_OPENED);
|
|
|
|
SET_BOOKMARK(&zb, lwb->lwb_blk.blk_cksum.zc_word[ZIL_ZC_OBJSET],
|
|
ZB_ZIL_OBJECT, ZB_ZIL_LEVEL,
|
|
lwb->lwb_blk.blk_cksum.zc_word[ZIL_ZC_SEQ]);
|
|
|
|
/* Lock so zil_sync() doesn't fastwrite_unmark after zio is created */
|
|
mutex_enter(&zilog->zl_lock);
|
|
if (lwb->lwb_root_zio == NULL) {
|
|
abd_t *lwb_abd = abd_get_from_buf(lwb->lwb_buf,
|
|
BP_GET_LSIZE(&lwb->lwb_blk));
|
|
|
|
if (!lwb->lwb_fastwrite) {
|
|
metaslab_fastwrite_mark(zilog->zl_spa, &lwb->lwb_blk);
|
|
lwb->lwb_fastwrite = 1;
|
|
}
|
|
|
|
if (!lwb->lwb_slog || zilog->zl_cur_used <= zil_slog_bulk)
|
|
prio = ZIO_PRIORITY_SYNC_WRITE;
|
|
else
|
|
prio = ZIO_PRIORITY_ASYNC_WRITE;
|
|
|
|
lwb->lwb_root_zio = zio_root(zilog->zl_spa,
|
|
zil_lwb_flush_vdevs_done, lwb, ZIO_FLAG_CANFAIL);
|
|
ASSERT3P(lwb->lwb_root_zio, !=, NULL);
|
|
|
|
lwb->lwb_write_zio = zio_rewrite(lwb->lwb_root_zio,
|
|
zilog->zl_spa, 0, &lwb->lwb_blk, lwb_abd,
|
|
BP_GET_LSIZE(&lwb->lwb_blk), zil_lwb_write_done, lwb,
|
|
prio, ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_PROPAGATE |
|
|
ZIO_FLAG_FASTWRITE, &zb);
|
|
ASSERT3P(lwb->lwb_write_zio, !=, NULL);
|
|
|
|
lwb->lwb_state = LWB_STATE_OPENED;
|
|
|
|
zil_lwb_set_zio_dependency(zilog, lwb);
|
|
zilog->zl_last_lwb_opened = lwb;
|
|
}
|
|
mutex_exit(&zilog->zl_lock);
|
|
|
|
ASSERT3P(lwb->lwb_root_zio, !=, NULL);
|
|
ASSERT3P(lwb->lwb_write_zio, !=, NULL);
|
|
ASSERT3S(lwb->lwb_state, ==, LWB_STATE_OPENED);
|
|
}
|
|
|
|
/*
|
|
* Define a limited set of intent log block sizes.
|
|
*
|
|
* These must be a multiple of 4KB. Note only the amount used (again
|
|
* aligned to 4KB) actually gets written. However, we can't always just
|
|
* allocate SPA_OLD_MAXBLOCKSIZE as the slog space could be exhausted.
|
|
*/
|
|
struct {
|
|
uint64_t limit;
|
|
uint64_t blksz;
|
|
} zil_block_buckets[] = {
|
|
{ 4096, 4096 }, /* non TX_WRITE */
|
|
{ 8192 + 4096, 8192 + 4096 }, /* database */
|
|
{ 32768 + 4096, 32768 + 4096 }, /* NFS writes */
|
|
{ 65536 + 4096, 65536 + 4096 }, /* 64KB writes */
|
|
{ 131072, 131072 }, /* < 128KB writes */
|
|
{ 131072 +4096, 65536 + 4096 }, /* 128KB writes */
|
|
{ UINT64_MAX, SPA_OLD_MAXBLOCKSIZE}, /* > 128KB writes */
|
|
};
|
|
|
|
/*
|
|
* Maximum block size used by the ZIL. This is picked up when the ZIL is
|
|
* initialized. Otherwise this should not be used directly; see
|
|
* zl_max_block_size instead.
|
|
*/
|
|
int zil_maxblocksize = SPA_OLD_MAXBLOCKSIZE;
|
|
|
|
/*
|
|
* Start a log block write and advance to the next log block.
|
|
* Calls are serialized.
|
|
*/
|
|
static lwb_t *
|
|
zil_lwb_write_issue(zilog_t *zilog, lwb_t *lwb)
|
|
{
|
|
lwb_t *nlwb = NULL;
|
|
zil_chain_t *zilc;
|
|
spa_t *spa = zilog->zl_spa;
|
|
blkptr_t *bp;
|
|
dmu_tx_t *tx;
|
|
uint64_t txg;
|
|
uint64_t zil_blksz, wsz;
|
|
int i, error;
|
|
boolean_t slog;
|
|
|
|
ASSERT(MUTEX_HELD(&zilog->zl_issuer_lock));
|
|
ASSERT3P(lwb->lwb_root_zio, !=, NULL);
|
|
ASSERT3P(lwb->lwb_write_zio, !=, NULL);
|
|
ASSERT3S(lwb->lwb_state, ==, LWB_STATE_OPENED);
|
|
|
|
if (BP_GET_CHECKSUM(&lwb->lwb_blk) == ZIO_CHECKSUM_ZILOG2) {
|
|
zilc = (zil_chain_t *)lwb->lwb_buf;
|
|
bp = &zilc->zc_next_blk;
|
|
} else {
|
|
zilc = (zil_chain_t *)(lwb->lwb_buf + lwb->lwb_sz);
|
|
bp = &zilc->zc_next_blk;
|
|
}
|
|
|
|
ASSERT(lwb->lwb_nused <= lwb->lwb_sz);
|
|
|
|
/*
|
|
* Allocate the next block and save its address in this block
|
|
* before writing it in order to establish the log chain.
|
|
* Note that if the allocation of nlwb synced before we wrote
|
|
* the block that points at it (lwb), we'd leak it if we crashed.
|
|
* Therefore, we don't do dmu_tx_commit() until zil_lwb_write_done().
|
|
* We dirty the dataset to ensure that zil_sync() will be called
|
|
* to clean up in the event of allocation failure or I/O failure.
|
|
*/
|
|
|
|
tx = dmu_tx_create(zilog->zl_os);
|
|
|
|
/*
|
|
* Since we are not going to create any new dirty data, and we
|
|
* can even help with clearing the existing dirty data, we
|
|
* should not be subject to the dirty data based delays. We
|
|
* use TXG_NOTHROTTLE to bypass the delay mechanism.
|
|
*/
|
|
VERIFY0(dmu_tx_assign(tx, TXG_WAIT | TXG_NOTHROTTLE));
|
|
|
|
dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx);
|
|
txg = dmu_tx_get_txg(tx);
|
|
|
|
lwb->lwb_tx = tx;
|
|
|
|
/*
|
|
* Log blocks are pre-allocated. Here we select the size of the next
|
|
* block, based on size used in the last block.
|
|
* - first find the smallest bucket that will fit the block from a
|
|
* limited set of block sizes. This is because it's faster to write
|
|
* blocks allocated from the same metaslab as they are adjacent or
|
|
* close.
|
|
* - next find the maximum from the new suggested size and an array of
|
|
* previous sizes. This lessens a picket fence effect of wrongly
|
|
* guessing the size if we have a stream of say 2k, 64k, 2k, 64k
|
|
* requests.
|
|
*
|
|
* Note we only write what is used, but we can't just allocate
|
|
* the maximum block size because we can exhaust the available
|
|
* pool log space.
|
|
*/
|
|
zil_blksz = zilog->zl_cur_used + sizeof (zil_chain_t);
|
|
for (i = 0; zil_blksz > zil_block_buckets[i].limit; i++)
|
|
continue;
|
|
zil_blksz = MIN(zil_block_buckets[i].blksz, zilog->zl_max_block_size);
|
|
zilog->zl_prev_blks[zilog->zl_prev_rotor] = zil_blksz;
|
|
for (i = 0; i < ZIL_PREV_BLKS; i++)
|
|
zil_blksz = MAX(zil_blksz, zilog->zl_prev_blks[i]);
|
|
zilog->zl_prev_rotor = (zilog->zl_prev_rotor + 1) & (ZIL_PREV_BLKS - 1);
|
|
|
|
BP_ZERO(bp);
|
|
error = zio_alloc_zil(spa, zilog->zl_os, txg, bp, zil_blksz, &slog);
|
|
if (slog) {
|
|
ZIL_STAT_BUMP(zil_itx_metaslab_slog_count);
|
|
ZIL_STAT_INCR(zil_itx_metaslab_slog_bytes, lwb->lwb_nused);
|
|
} else {
|
|
ZIL_STAT_BUMP(zil_itx_metaslab_normal_count);
|
|
ZIL_STAT_INCR(zil_itx_metaslab_normal_bytes, lwb->lwb_nused);
|
|
}
|
|
if (error == 0) {
|
|
ASSERT3U(bp->blk_birth, ==, txg);
|
|
bp->blk_cksum = lwb->lwb_blk.blk_cksum;
|
|
bp->blk_cksum.zc_word[ZIL_ZC_SEQ]++;
|
|
|
|
/*
|
|
* Allocate a new log write block (lwb).
|
|
*/
|
|
nlwb = zil_alloc_lwb(zilog, bp, slog, txg, TRUE);
|
|
}
|
|
|
|
if (BP_GET_CHECKSUM(&lwb->lwb_blk) == ZIO_CHECKSUM_ZILOG2) {
|
|
/* For Slim ZIL only write what is used. */
|
|
wsz = P2ROUNDUP_TYPED(lwb->lwb_nused, ZIL_MIN_BLKSZ, uint64_t);
|
|
ASSERT3U(wsz, <=, lwb->lwb_sz);
|
|
zio_shrink(lwb->lwb_write_zio, wsz);
|
|
|
|
} else {
|
|
wsz = lwb->lwb_sz;
|
|
}
|
|
|
|
zilc->zc_pad = 0;
|
|
zilc->zc_nused = lwb->lwb_nused;
|
|
zilc->zc_eck.zec_cksum = lwb->lwb_blk.blk_cksum;
|
|
|
|
/*
|
|
* clear unused data for security
|
|
*/
|
|
bzero(lwb->lwb_buf + lwb->lwb_nused, wsz - lwb->lwb_nused);
|
|
|
|
spa_config_enter(zilog->zl_spa, SCL_STATE, lwb, RW_READER);
|
|
|
|
zil_lwb_add_block(lwb, &lwb->lwb_blk);
|
|
lwb->lwb_issued_timestamp = gethrtime();
|
|
lwb->lwb_state = LWB_STATE_ISSUED;
|
|
|
|
zio_nowait(lwb->lwb_root_zio);
|
|
zio_nowait(lwb->lwb_write_zio);
|
|
|
|
/*
|
|
* If there was an allocation failure then nlwb will be null which
|
|
* forces a txg_wait_synced().
|
|
*/
|
|
return (nlwb);
|
|
}
|
|
|
|
/*
|
|
* Maximum amount of write data that can be put into single log block.
|
|
*/
|
|
uint64_t
|
|
zil_max_log_data(zilog_t *zilog)
|
|
{
|
|
return (zilog->zl_max_block_size -
|
|
sizeof (zil_chain_t) - sizeof (lr_write_t));
|
|
}
|
|
|
|
/*
|
|
* Maximum amount of log space we agree to waste to reduce number of
|
|
* WR_NEED_COPY chunks to reduce zl_get_data() overhead (~12%).
|
|
*/
|
|
static inline uint64_t
|
|
zil_max_waste_space(zilog_t *zilog)
|
|
{
|
|
return (zil_max_log_data(zilog) / 8);
|
|
}
|
|
|
|
/*
|
|
* Maximum amount of write data for WR_COPIED. For correctness, consumers
|
|
* must fall back to WR_NEED_COPY if we can't fit the entire record into one
|
|
* maximum sized log block, because each WR_COPIED record must fit in a
|
|
* single log block. For space efficiency, we want to fit two records into a
|
|
* max-sized log block.
|
|
*/
|
|
uint64_t
|
|
zil_max_copied_data(zilog_t *zilog)
|
|
{
|
|
return ((zilog->zl_max_block_size - sizeof (zil_chain_t)) / 2 -
|
|
sizeof (lr_write_t));
|
|
}
|
|
|
|
static lwb_t *
|
|
zil_lwb_commit(zilog_t *zilog, itx_t *itx, lwb_t *lwb)
|
|
{
|
|
lr_t *lrcb, *lrc;
|
|
lr_write_t *lrwb, *lrw;
|
|
char *lr_buf;
|
|
uint64_t dlen, dnow, lwb_sp, reclen, txg, max_log_data;
|
|
|
|
ASSERT(MUTEX_HELD(&zilog->zl_issuer_lock));
|
|
ASSERT3P(lwb, !=, NULL);
|
|
ASSERT3P(lwb->lwb_buf, !=, NULL);
|
|
|
|
zil_lwb_write_open(zilog, lwb);
|
|
|
|
lrc = &itx->itx_lr;
|
|
lrw = (lr_write_t *)lrc;
|
|
|
|
/*
|
|
* A commit itx doesn't represent any on-disk state; instead
|
|
* it's simply used as a place holder on the commit list, and
|
|
* provides a mechanism for attaching a "commit waiter" onto the
|
|
* correct lwb (such that the waiter can be signalled upon
|
|
* completion of that lwb). Thus, we don't process this itx's
|
|
* log record if it's a commit itx (these itx's don't have log
|
|
* records), and instead link the itx's waiter onto the lwb's
|
|
* list of waiters.
|
|
*
|
|
* For more details, see the comment above zil_commit().
|
|
*/
|
|
if (lrc->lrc_txtype == TX_COMMIT) {
|
|
mutex_enter(&zilog->zl_lock);
|
|
zil_commit_waiter_link_lwb(itx->itx_private, lwb);
|
|
itx->itx_private = NULL;
|
|
mutex_exit(&zilog->zl_lock);
|
|
return (lwb);
|
|
}
|
|
|
|
if (lrc->lrc_txtype == TX_WRITE && itx->itx_wr_state == WR_NEED_COPY) {
|
|
dlen = P2ROUNDUP_TYPED(
|
|
lrw->lr_length, sizeof (uint64_t), uint64_t);
|
|
} else {
|
|
dlen = 0;
|
|
}
|
|
reclen = lrc->lrc_reclen;
|
|
zilog->zl_cur_used += (reclen + dlen);
|
|
txg = lrc->lrc_txg;
|
|
|
|
ASSERT3U(zilog->zl_cur_used, <, UINT64_MAX - (reclen + dlen));
|
|
|
|
cont:
|
|
/*
|
|
* If this record won't fit in the current log block, start a new one.
|
|
* For WR_NEED_COPY optimize layout for minimal number of chunks.
|
|
*/
|
|
lwb_sp = lwb->lwb_sz - lwb->lwb_nused;
|
|
max_log_data = zil_max_log_data(zilog);
|
|
if (reclen > lwb_sp || (reclen + dlen > lwb_sp &&
|
|
lwb_sp < zil_max_waste_space(zilog) &&
|
|
(dlen % max_log_data == 0 ||
|
|
lwb_sp < reclen + dlen % max_log_data))) {
|
|
lwb = zil_lwb_write_issue(zilog, lwb);
|
|
if (lwb == NULL)
|
|
return (NULL);
|
|
zil_lwb_write_open(zilog, lwb);
|
|
ASSERT(LWB_EMPTY(lwb));
|
|
lwb_sp = lwb->lwb_sz - lwb->lwb_nused;
|
|
|
|
/*
|
|
* There must be enough space in the new, empty log block to
|
|
* hold reclen. For WR_COPIED, we need to fit the whole
|
|
* record in one block, and reclen is the header size + the
|
|
* data size. For WR_NEED_COPY, we can create multiple
|
|
* records, splitting the data into multiple blocks, so we
|
|
* only need to fit one word of data per block; in this case
|
|
* reclen is just the header size (no data).
|
|
*/
|
|
ASSERT3U(reclen + MIN(dlen, sizeof (uint64_t)), <=, lwb_sp);
|
|
}
|
|
|
|
dnow = MIN(dlen, lwb_sp - reclen);
|
|
lr_buf = lwb->lwb_buf + lwb->lwb_nused;
|
|
bcopy(lrc, lr_buf, reclen);
|
|
lrcb = (lr_t *)lr_buf; /* Like lrc, but inside lwb. */
|
|
lrwb = (lr_write_t *)lrcb; /* Like lrw, but inside lwb. */
|
|
|
|
ZIL_STAT_BUMP(zil_itx_count);
|
|
|
|
/*
|
|
* If it's a write, fetch the data or get its blkptr as appropriate.
|
|
*/
|
|
if (lrc->lrc_txtype == TX_WRITE) {
|
|
if (txg > spa_freeze_txg(zilog->zl_spa))
|
|
txg_wait_synced(zilog->zl_dmu_pool, txg);
|
|
if (itx->itx_wr_state == WR_COPIED) {
|
|
ZIL_STAT_BUMP(zil_itx_copied_count);
|
|
ZIL_STAT_INCR(zil_itx_copied_bytes, lrw->lr_length);
|
|
} else {
|
|
char *dbuf;
|
|
int error;
|
|
|
|
if (itx->itx_wr_state == WR_NEED_COPY) {
|
|
dbuf = lr_buf + reclen;
|
|
lrcb->lrc_reclen += dnow;
|
|
if (lrwb->lr_length > dnow)
|
|
lrwb->lr_length = dnow;
|
|
lrw->lr_offset += dnow;
|
|
lrw->lr_length -= dnow;
|
|
ZIL_STAT_BUMP(zil_itx_needcopy_count);
|
|
ZIL_STAT_INCR(zil_itx_needcopy_bytes, dnow);
|
|
} else {
|
|
ASSERT3S(itx->itx_wr_state, ==, WR_INDIRECT);
|
|
dbuf = NULL;
|
|
ZIL_STAT_BUMP(zil_itx_indirect_count);
|
|
ZIL_STAT_INCR(zil_itx_indirect_bytes,
|
|
lrw->lr_length);
|
|
}
|
|
|
|
/*
|
|
* We pass in the "lwb_write_zio" rather than
|
|
* "lwb_root_zio" so that the "lwb_write_zio"
|
|
* becomes the parent of any zio's created by
|
|
* the "zl_get_data" callback. The vdevs are
|
|
* flushed after the "lwb_write_zio" completes,
|
|
* so we want to make sure that completion
|
|
* callback waits for these additional zio's,
|
|
* such that the vdevs used by those zio's will
|
|
* be included in the lwb's vdev tree, and those
|
|
* vdevs will be properly flushed. If we passed
|
|
* in "lwb_root_zio" here, then these additional
|
|
* vdevs may not be flushed; e.g. if these zio's
|
|
* completed after "lwb_write_zio" completed.
|
|
*/
|
|
error = zilog->zl_get_data(itx->itx_private,
|
|
lrwb, dbuf, lwb, lwb->lwb_write_zio);
|
|
|
|
if (error == EIO) {
|
|
txg_wait_synced(zilog->zl_dmu_pool, txg);
|
|
return (lwb);
|
|
}
|
|
if (error != 0) {
|
|
ASSERT(error == ENOENT || error == EEXIST ||
|
|
error == EALREADY);
|
|
return (lwb);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* We're actually making an entry, so update lrc_seq to be the
|
|
* log record sequence number. Note that this is generally not
|
|
* equal to the itx sequence number because not all transactions
|
|
* are synchronous, and sometimes spa_sync() gets there first.
|
|
*/
|
|
lrcb->lrc_seq = ++zilog->zl_lr_seq;
|
|
lwb->lwb_nused += reclen + dnow;
|
|
|
|
zil_lwb_add_txg(lwb, txg);
|
|
|
|
ASSERT3U(lwb->lwb_nused, <=, lwb->lwb_sz);
|
|
ASSERT0(P2PHASE(lwb->lwb_nused, sizeof (uint64_t)));
|
|
|
|
dlen -= dnow;
|
|
if (dlen > 0) {
|
|
zilog->zl_cur_used += reclen;
|
|
goto cont;
|
|
}
|
|
|
|
return (lwb);
|
|
}
|
|
|
|
itx_t *
|
|
zil_itx_create(uint64_t txtype, size_t lrsize)
|
|
{
|
|
size_t itxsize;
|
|
itx_t *itx;
|
|
|
|
lrsize = P2ROUNDUP_TYPED(lrsize, sizeof (uint64_t), size_t);
|
|
itxsize = offsetof(itx_t, itx_lr) + lrsize;
|
|
|
|
itx = zio_data_buf_alloc(itxsize);
|
|
itx->itx_lr.lrc_txtype = txtype;
|
|
itx->itx_lr.lrc_reclen = lrsize;
|
|
itx->itx_lr.lrc_seq = 0; /* defensive */
|
|
itx->itx_sync = B_TRUE; /* default is synchronous */
|
|
itx->itx_callback = NULL;
|
|
itx->itx_callback_data = NULL;
|
|
itx->itx_size = itxsize;
|
|
|
|
return (itx);
|
|
}
|
|
|
|
void
|
|
zil_itx_destroy(itx_t *itx)
|
|
{
|
|
IMPLY(itx->itx_lr.lrc_txtype == TX_COMMIT, itx->itx_callback == NULL);
|
|
IMPLY(itx->itx_callback != NULL, itx->itx_lr.lrc_txtype != TX_COMMIT);
|
|
|
|
if (itx->itx_callback != NULL)
|
|
itx->itx_callback(itx->itx_callback_data);
|
|
|
|
zio_data_buf_free(itx, itx->itx_size);
|
|
}
|
|
|
|
/*
|
|
* Free up the sync and async itxs. The itxs_t has already been detached
|
|
* so no locks are needed.
|
|
*/
|
|
static void
|
|
zil_itxg_clean(itxs_t *itxs)
|
|
{
|
|
itx_t *itx;
|
|
list_t *list;
|
|
avl_tree_t *t;
|
|
void *cookie;
|
|
itx_async_node_t *ian;
|
|
|
|
list = &itxs->i_sync_list;
|
|
while ((itx = list_head(list)) != NULL) {
|
|
/*
|
|
* In the general case, commit itxs will not be found
|
|
* here, as they'll be committed to an lwb via
|
|
* zil_lwb_commit(), and free'd in that function. Having
|
|
* said that, it is still possible for commit itxs to be
|
|
* found here, due to the following race:
|
|
*
|
|
* - a thread calls zil_commit() which assigns the
|
|
* commit itx to a per-txg i_sync_list
|
|
* - zil_itxg_clean() is called (e.g. via spa_sync())
|
|
* while the waiter is still on the i_sync_list
|
|
*
|
|
* There's nothing to prevent syncing the txg while the
|
|
* waiter is on the i_sync_list. This normally doesn't
|
|
* happen because spa_sync() is slower than zil_commit(),
|
|
* but if zil_commit() calls txg_wait_synced() (e.g.
|
|
* because zil_create() or zil_commit_writer_stall() is
|
|
* called) we will hit this case.
|
|
*/
|
|
if (itx->itx_lr.lrc_txtype == TX_COMMIT)
|
|
zil_commit_waiter_skip(itx->itx_private);
|
|
|
|
list_remove(list, itx);
|
|
zil_itx_destroy(itx);
|
|
}
|
|
|
|
cookie = NULL;
|
|
t = &itxs->i_async_tree;
|
|
while ((ian = avl_destroy_nodes(t, &cookie)) != NULL) {
|
|
list = &ian->ia_list;
|
|
while ((itx = list_head(list)) != NULL) {
|
|
list_remove(list, itx);
|
|
/* commit itxs should never be on the async lists. */
|
|
ASSERT3U(itx->itx_lr.lrc_txtype, !=, TX_COMMIT);
|
|
zil_itx_destroy(itx);
|
|
}
|
|
list_destroy(list);
|
|
kmem_free(ian, sizeof (itx_async_node_t));
|
|
}
|
|
avl_destroy(t);
|
|
|
|
kmem_free(itxs, sizeof (itxs_t));
|
|
}
|
|
|
|
static int
|
|
zil_aitx_compare(const void *x1, const void *x2)
|
|
{
|
|
const uint64_t o1 = ((itx_async_node_t *)x1)->ia_foid;
|
|
const uint64_t o2 = ((itx_async_node_t *)x2)->ia_foid;
|
|
|
|
return (TREE_CMP(o1, o2));
|
|
}
|
|
|
|
/*
|
|
* Remove all async itx with the given oid.
|
|
*/
|
|
void
|
|
zil_remove_async(zilog_t *zilog, uint64_t oid)
|
|
{
|
|
uint64_t otxg, txg;
|
|
itx_async_node_t *ian;
|
|
avl_tree_t *t;
|
|
avl_index_t where;
|
|
list_t clean_list;
|
|
itx_t *itx;
|
|
|
|
ASSERT(oid != 0);
|
|
list_create(&clean_list, sizeof (itx_t), offsetof(itx_t, itx_node));
|
|
|
|
if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) /* ziltest support */
|
|
otxg = ZILTEST_TXG;
|
|
else
|
|
otxg = spa_last_synced_txg(zilog->zl_spa) + 1;
|
|
|
|
for (txg = otxg; txg < (otxg + TXG_CONCURRENT_STATES); txg++) {
|
|
itxg_t *itxg = &zilog->zl_itxg[txg & TXG_MASK];
|
|
|
|
mutex_enter(&itxg->itxg_lock);
|
|
if (itxg->itxg_txg != txg) {
|
|
mutex_exit(&itxg->itxg_lock);
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Locate the object node and append its list.
|
|
*/
|
|
t = &itxg->itxg_itxs->i_async_tree;
|
|
ian = avl_find(t, &oid, &where);
|
|
if (ian != NULL)
|
|
list_move_tail(&clean_list, &ian->ia_list);
|
|
mutex_exit(&itxg->itxg_lock);
|
|
}
|
|
while ((itx = list_head(&clean_list)) != NULL) {
|
|
list_remove(&clean_list, itx);
|
|
/* commit itxs should never be on the async lists. */
|
|
ASSERT3U(itx->itx_lr.lrc_txtype, !=, TX_COMMIT);
|
|
zil_itx_destroy(itx);
|
|
}
|
|
list_destroy(&clean_list);
|
|
}
|
|
|
|
void
|
|
zil_itx_assign(zilog_t *zilog, itx_t *itx, dmu_tx_t *tx)
|
|
{
|
|
uint64_t txg;
|
|
itxg_t *itxg;
|
|
itxs_t *itxs, *clean = NULL;
|
|
|
|
/*
|
|
* Ensure the data of a renamed file is committed before the rename.
|
|
*/
|
|
if ((itx->itx_lr.lrc_txtype & ~TX_CI) == TX_RENAME)
|
|
zil_async_to_sync(zilog, itx->itx_oid);
|
|
|
|
if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX)
|
|
txg = ZILTEST_TXG;
|
|
else
|
|
txg = dmu_tx_get_txg(tx);
|
|
|
|
itxg = &zilog->zl_itxg[txg & TXG_MASK];
|
|
mutex_enter(&itxg->itxg_lock);
|
|
itxs = itxg->itxg_itxs;
|
|
if (itxg->itxg_txg != txg) {
|
|
if (itxs != NULL) {
|
|
/*
|
|
* The zil_clean callback hasn't got around to cleaning
|
|
* this itxg. Save the itxs for release below.
|
|
* This should be rare.
|
|
*/
|
|
zfs_dbgmsg("zil_itx_assign: missed itx cleanup for "
|
|
"txg %llu", itxg->itxg_txg);
|
|
clean = itxg->itxg_itxs;
|
|
}
|
|
itxg->itxg_txg = txg;
|
|
itxs = itxg->itxg_itxs = kmem_zalloc(sizeof (itxs_t),
|
|
KM_SLEEP);
|
|
|
|
list_create(&itxs->i_sync_list, sizeof (itx_t),
|
|
offsetof(itx_t, itx_node));
|
|
avl_create(&itxs->i_async_tree, zil_aitx_compare,
|
|
sizeof (itx_async_node_t),
|
|
offsetof(itx_async_node_t, ia_node));
|
|
}
|
|
if (itx->itx_sync) {
|
|
list_insert_tail(&itxs->i_sync_list, itx);
|
|
} else {
|
|
avl_tree_t *t = &itxs->i_async_tree;
|
|
uint64_t foid =
|
|
LR_FOID_GET_OBJ(((lr_ooo_t *)&itx->itx_lr)->lr_foid);
|
|
itx_async_node_t *ian;
|
|
avl_index_t where;
|
|
|
|
ian = avl_find(t, &foid, &where);
|
|
if (ian == NULL) {
|
|
ian = kmem_alloc(sizeof (itx_async_node_t),
|
|
KM_SLEEP);
|
|
list_create(&ian->ia_list, sizeof (itx_t),
|
|
offsetof(itx_t, itx_node));
|
|
ian->ia_foid = foid;
|
|
avl_insert(t, ian, where);
|
|
}
|
|
list_insert_tail(&ian->ia_list, itx);
|
|
}
|
|
|
|
itx->itx_lr.lrc_txg = dmu_tx_get_txg(tx);
|
|
|
|
/*
|
|
* We don't want to dirty the ZIL using ZILTEST_TXG, because
|
|
* zil_clean() will never be called using ZILTEST_TXG. Thus, we
|
|
* need to be careful to always dirty the ZIL using the "real"
|
|
* TXG (not itxg_txg) even when the SPA is frozen.
|
|
*/
|
|
zilog_dirty(zilog, dmu_tx_get_txg(tx));
|
|
mutex_exit(&itxg->itxg_lock);
|
|
|
|
/* Release the old itxs now we've dropped the lock */
|
|
if (clean != NULL)
|
|
zil_itxg_clean(clean);
|
|
}
|
|
|
|
/*
|
|
* If there are any in-memory intent log transactions which have now been
|
|
* synced then start up a taskq to free them. We should only do this after we
|
|
* have written out the uberblocks (i.e. txg has been committed) so that
|
|
* don't inadvertently clean out in-memory log records that would be required
|
|
* by zil_commit().
|
|
*/
|
|
void
|
|
zil_clean(zilog_t *zilog, uint64_t synced_txg)
|
|
{
|
|
itxg_t *itxg = &zilog->zl_itxg[synced_txg & TXG_MASK];
|
|
itxs_t *clean_me;
|
|
|
|
ASSERT3U(synced_txg, <, ZILTEST_TXG);
|
|
|
|
mutex_enter(&itxg->itxg_lock);
|
|
if (itxg->itxg_itxs == NULL || itxg->itxg_txg == ZILTEST_TXG) {
|
|
mutex_exit(&itxg->itxg_lock);
|
|
return;
|
|
}
|
|
ASSERT3U(itxg->itxg_txg, <=, synced_txg);
|
|
ASSERT3U(itxg->itxg_txg, !=, 0);
|
|
clean_me = itxg->itxg_itxs;
|
|
itxg->itxg_itxs = NULL;
|
|
itxg->itxg_txg = 0;
|
|
mutex_exit(&itxg->itxg_lock);
|
|
/*
|
|
* Preferably start a task queue to free up the old itxs but
|
|
* if taskq_dispatch can't allocate resources to do that then
|
|
* free it in-line. This should be rare. Note, using TQ_SLEEP
|
|
* created a bad performance problem.
|
|
*/
|
|
ASSERT3P(zilog->zl_dmu_pool, !=, NULL);
|
|
ASSERT3P(zilog->zl_dmu_pool->dp_zil_clean_taskq, !=, NULL);
|
|
taskqid_t id = taskq_dispatch(zilog->zl_dmu_pool->dp_zil_clean_taskq,
|
|
(void (*)(void *))zil_itxg_clean, clean_me, TQ_NOSLEEP);
|
|
if (id == TASKQID_INVALID)
|
|
zil_itxg_clean(clean_me);
|
|
}
|
|
|
|
/*
|
|
* This function will traverse the queue of itxs that need to be
|
|
* committed, and move them onto the ZIL's zl_itx_commit_list.
|
|
*/
|
|
static void
|
|
zil_get_commit_list(zilog_t *zilog)
|
|
{
|
|
uint64_t otxg, txg;
|
|
list_t *commit_list = &zilog->zl_itx_commit_list;
|
|
|
|
ASSERT(MUTEX_HELD(&zilog->zl_issuer_lock));
|
|
|
|
if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) /* ziltest support */
|
|
otxg = ZILTEST_TXG;
|
|
else
|
|
otxg = spa_last_synced_txg(zilog->zl_spa) + 1;
|
|
|
|
/*
|
|
* This is inherently racy, since there is nothing to prevent
|
|
* the last synced txg from changing. That's okay since we'll
|
|
* only commit things in the future.
|
|
*/
|
|
for (txg = otxg; txg < (otxg + TXG_CONCURRENT_STATES); txg++) {
|
|
itxg_t *itxg = &zilog->zl_itxg[txg & TXG_MASK];
|
|
|
|
mutex_enter(&itxg->itxg_lock);
|
|
if (itxg->itxg_txg != txg) {
|
|
mutex_exit(&itxg->itxg_lock);
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* If we're adding itx records to the zl_itx_commit_list,
|
|
* then the zil better be dirty in this "txg". We can assert
|
|
* that here since we're holding the itxg_lock which will
|
|
* prevent spa_sync from cleaning it. Once we add the itxs
|
|
* to the zl_itx_commit_list we must commit it to disk even
|
|
* if it's unnecessary (i.e. the txg was synced).
|
|
*/
|
|
ASSERT(zilog_is_dirty_in_txg(zilog, txg) ||
|
|
spa_freeze_txg(zilog->zl_spa) != UINT64_MAX);
|
|
list_move_tail(commit_list, &itxg->itxg_itxs->i_sync_list);
|
|
|
|
mutex_exit(&itxg->itxg_lock);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Move the async itxs for a specified object to commit into sync lists.
|
|
*/
|
|
void
|
|
zil_async_to_sync(zilog_t *zilog, uint64_t foid)
|
|
{
|
|
uint64_t otxg, txg;
|
|
itx_async_node_t *ian;
|
|
avl_tree_t *t;
|
|
avl_index_t where;
|
|
|
|
if (spa_freeze_txg(zilog->zl_spa) != UINT64_MAX) /* ziltest support */
|
|
otxg = ZILTEST_TXG;
|
|
else
|
|
otxg = spa_last_synced_txg(zilog->zl_spa) + 1;
|
|
|
|
/*
|
|
* This is inherently racy, since there is nothing to prevent
|
|
* the last synced txg from changing.
|
|
*/
|
|
for (txg = otxg; txg < (otxg + TXG_CONCURRENT_STATES); txg++) {
|
|
itxg_t *itxg = &zilog->zl_itxg[txg & TXG_MASK];
|
|
|
|
mutex_enter(&itxg->itxg_lock);
|
|
if (itxg->itxg_txg != txg) {
|
|
mutex_exit(&itxg->itxg_lock);
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* If a foid is specified then find that node and append its
|
|
* list. Otherwise walk the tree appending all the lists
|
|
* to the sync list. We add to the end rather than the
|
|
* beginning to ensure the create has happened.
|
|
*/
|
|
t = &itxg->itxg_itxs->i_async_tree;
|
|
if (foid != 0) {
|
|
ian = avl_find(t, &foid, &where);
|
|
if (ian != NULL) {
|
|
list_move_tail(&itxg->itxg_itxs->i_sync_list,
|
|
&ian->ia_list);
|
|
}
|
|
} else {
|
|
void *cookie = NULL;
|
|
|
|
while ((ian = avl_destroy_nodes(t, &cookie)) != NULL) {
|
|
list_move_tail(&itxg->itxg_itxs->i_sync_list,
|
|
&ian->ia_list);
|
|
list_destroy(&ian->ia_list);
|
|
kmem_free(ian, sizeof (itx_async_node_t));
|
|
}
|
|
}
|
|
mutex_exit(&itxg->itxg_lock);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* This function will prune commit itxs that are at the head of the
|
|
* commit list (it won't prune past the first non-commit itx), and
|
|
* either: a) attach them to the last lwb that's still pending
|
|
* completion, or b) skip them altogether.
|
|
*
|
|
* This is used as a performance optimization to prevent commit itxs
|
|
* from generating new lwbs when it's unnecessary to do so.
|
|
*/
|
|
static void
|
|
zil_prune_commit_list(zilog_t *zilog)
|
|
{
|
|
itx_t *itx;
|
|
|
|
ASSERT(MUTEX_HELD(&zilog->zl_issuer_lock));
|
|
|
|
while ((itx = list_head(&zilog->zl_itx_commit_list)) != NULL) {
|
|
lr_t *lrc = &itx->itx_lr;
|
|
if (lrc->lrc_txtype != TX_COMMIT)
|
|
break;
|
|
|
|
mutex_enter(&zilog->zl_lock);
|
|
|
|
lwb_t *last_lwb = zilog->zl_last_lwb_opened;
|
|
if (last_lwb == NULL ||
|
|
last_lwb->lwb_state == LWB_STATE_FLUSH_DONE) {
|
|
/*
|
|
* All of the itxs this waiter was waiting on
|
|
* must have already completed (or there were
|
|
* never any itx's for it to wait on), so it's
|
|
* safe to skip this waiter and mark it done.
|
|
*/
|
|
zil_commit_waiter_skip(itx->itx_private);
|
|
} else {
|
|
zil_commit_waiter_link_lwb(itx->itx_private, last_lwb);
|
|
itx->itx_private = NULL;
|
|
}
|
|
|
|
mutex_exit(&zilog->zl_lock);
|
|
|
|
list_remove(&zilog->zl_itx_commit_list, itx);
|
|
zil_itx_destroy(itx);
|
|
}
|
|
|
|
IMPLY(itx != NULL, itx->itx_lr.lrc_txtype != TX_COMMIT);
|
|
}
|
|
|
|
static void
|
|
zil_commit_writer_stall(zilog_t *zilog)
|
|
{
|
|
/*
|
|
* When zio_alloc_zil() fails to allocate the next lwb block on
|
|
* disk, we must call txg_wait_synced() to ensure all of the
|
|
* lwbs in the zilog's zl_lwb_list are synced and then freed (in
|
|
* zil_sync()), such that any subsequent ZIL writer (i.e. a call
|
|
* to zil_process_commit_list()) will have to call zil_create(),
|
|
* and start a new ZIL chain.
|
|
*
|
|
* Since zil_alloc_zil() failed, the lwb that was previously
|
|
* issued does not have a pointer to the "next" lwb on disk.
|
|
* Thus, if another ZIL writer thread was to allocate the "next"
|
|
* on-disk lwb, that block could be leaked in the event of a
|
|
* crash (because the previous lwb on-disk would not point to
|
|
* it).
|
|
*
|
|
* We must hold the zilog's zl_issuer_lock while we do this, to
|
|
* ensure no new threads enter zil_process_commit_list() until
|
|
* all lwb's in the zl_lwb_list have been synced and freed
|
|
* (which is achieved via the txg_wait_synced() call).
|
|
*/
|
|
ASSERT(MUTEX_HELD(&zilog->zl_issuer_lock));
|
|
txg_wait_synced(zilog->zl_dmu_pool, 0);
|
|
ASSERT3P(list_tail(&zilog->zl_lwb_list), ==, NULL);
|
|
}
|
|
|
|
/*
|
|
* This function will traverse the commit list, creating new lwbs as
|
|
* needed, and committing the itxs from the commit list to these newly
|
|
* created lwbs. Additionally, as a new lwb is created, the previous
|
|
* lwb will be issued to the zio layer to be written to disk.
|
|
*/
|
|
static void
|
|
zil_process_commit_list(zilog_t *zilog)
|
|
{
|
|
spa_t *spa = zilog->zl_spa;
|
|
list_t nolwb_itxs;
|
|
list_t nolwb_waiters;
|
|
lwb_t *lwb;
|
|
itx_t *itx;
|
|
|
|
ASSERT(MUTEX_HELD(&zilog->zl_issuer_lock));
|
|
|
|
/*
|
|
* Return if there's nothing to commit before we dirty the fs by
|
|
* calling zil_create().
|
|
*/
|
|
if (list_head(&zilog->zl_itx_commit_list) == NULL)
|
|
return;
|
|
|
|
list_create(&nolwb_itxs, sizeof (itx_t), offsetof(itx_t, itx_node));
|
|
list_create(&nolwb_waiters, sizeof (zil_commit_waiter_t),
|
|
offsetof(zil_commit_waiter_t, zcw_node));
|
|
|
|
lwb = list_tail(&zilog->zl_lwb_list);
|
|
if (lwb == NULL) {
|
|
lwb = zil_create(zilog);
|
|
} else {
|
|
ASSERT3S(lwb->lwb_state, !=, LWB_STATE_ISSUED);
|
|
ASSERT3S(lwb->lwb_state, !=, LWB_STATE_WRITE_DONE);
|
|
ASSERT3S(lwb->lwb_state, !=, LWB_STATE_FLUSH_DONE);
|
|
}
|
|
|
|
while ((itx = list_head(&zilog->zl_itx_commit_list)) != NULL) {
|
|
lr_t *lrc = &itx->itx_lr;
|
|
uint64_t txg = lrc->lrc_txg;
|
|
|
|
ASSERT3U(txg, !=, 0);
|
|
|
|
if (lrc->lrc_txtype == TX_COMMIT) {
|
|
DTRACE_PROBE2(zil__process__commit__itx,
|
|
zilog_t *, zilog, itx_t *, itx);
|
|
} else {
|
|
DTRACE_PROBE2(zil__process__normal__itx,
|
|
zilog_t *, zilog, itx_t *, itx);
|
|
}
|
|
|
|
list_remove(&zilog->zl_itx_commit_list, itx);
|
|
|
|
boolean_t synced = txg <= spa_last_synced_txg(spa);
|
|
boolean_t frozen = txg > spa_freeze_txg(spa);
|
|
|
|
/*
|
|
* If the txg of this itx has already been synced out, then
|
|
* we don't need to commit this itx to an lwb. This is
|
|
* because the data of this itx will have already been
|
|
* written to the main pool. This is inherently racy, and
|
|
* it's still ok to commit an itx whose txg has already
|
|
* been synced; this will result in a write that's
|
|
* unnecessary, but will do no harm.
|
|
*
|
|
* With that said, we always want to commit TX_COMMIT itxs
|
|
* to an lwb, regardless of whether or not that itx's txg
|
|
* has been synced out. We do this to ensure any OPENED lwb
|
|
* will always have at least one zil_commit_waiter_t linked
|
|
* to the lwb.
|
|
*
|
|
* As a counter-example, if we skipped TX_COMMIT itx's
|
|
* whose txg had already been synced, the following
|
|
* situation could occur if we happened to be racing with
|
|
* spa_sync:
|
|
*
|
|
* 1. We commit a non-TX_COMMIT itx to an lwb, where the
|
|
* itx's txg is 10 and the last synced txg is 9.
|
|
* 2. spa_sync finishes syncing out txg 10.
|
|
* 3. We move to the next itx in the list, it's a TX_COMMIT
|
|
* whose txg is 10, so we skip it rather than committing
|
|
* it to the lwb used in (1).
|
|
*
|
|
* If the itx that is skipped in (3) is the last TX_COMMIT
|
|
* itx in the commit list, than it's possible for the lwb
|
|
* used in (1) to remain in the OPENED state indefinitely.
|
|
*
|
|
* To prevent the above scenario from occurring, ensuring
|
|
* that once an lwb is OPENED it will transition to ISSUED
|
|
* and eventually DONE, we always commit TX_COMMIT itx's to
|
|
* an lwb here, even if that itx's txg has already been
|
|
* synced.
|
|
*
|
|
* Finally, if the pool is frozen, we _always_ commit the
|
|
* itx. The point of freezing the pool is to prevent data
|
|
* from being written to the main pool via spa_sync, and
|
|
* instead rely solely on the ZIL to persistently store the
|
|
* data; i.e. when the pool is frozen, the last synced txg
|
|
* value can't be trusted.
|
|
*/
|
|
if (frozen || !synced || lrc->lrc_txtype == TX_COMMIT) {
|
|
if (lwb != NULL) {
|
|
lwb = zil_lwb_commit(zilog, itx, lwb);
|
|
|
|
if (lwb == NULL)
|
|
list_insert_tail(&nolwb_itxs, itx);
|
|
else
|
|
list_insert_tail(&lwb->lwb_itxs, itx);
|
|
} else {
|
|
if (lrc->lrc_txtype == TX_COMMIT) {
|
|
zil_commit_waiter_link_nolwb(
|
|
itx->itx_private, &nolwb_waiters);
|
|
}
|
|
|
|
list_insert_tail(&nolwb_itxs, itx);
|
|
}
|
|
} else {
|
|
ASSERT3S(lrc->lrc_txtype, !=, TX_COMMIT);
|
|
zil_itx_destroy(itx);
|
|
}
|
|
}
|
|
|
|
if (lwb == NULL) {
|
|
/*
|
|
* This indicates zio_alloc_zil() failed to allocate the
|
|
* "next" lwb on-disk. When this happens, we must stall
|
|
* the ZIL write pipeline; see the comment within
|
|
* zil_commit_writer_stall() for more details.
|
|
*/
|
|
zil_commit_writer_stall(zilog);
|
|
|
|
/*
|
|
* Additionally, we have to signal and mark the "nolwb"
|
|
* waiters as "done" here, since without an lwb, we
|
|
* can't do this via zil_lwb_flush_vdevs_done() like
|
|
* normal.
|
|
*/
|
|
zil_commit_waiter_t *zcw;
|
|
while ((zcw = list_head(&nolwb_waiters)) != NULL) {
|
|
zil_commit_waiter_skip(zcw);
|
|
list_remove(&nolwb_waiters, zcw);
|
|
}
|
|
|
|
/*
|
|
* And finally, we have to destroy the itx's that
|
|
* couldn't be committed to an lwb; this will also call
|
|
* the itx's callback if one exists for the itx.
|
|
*/
|
|
while ((itx = list_head(&nolwb_itxs)) != NULL) {
|
|
list_remove(&nolwb_itxs, itx);
|
|
zil_itx_destroy(itx);
|
|
}
|
|
} else {
|
|
ASSERT(list_is_empty(&nolwb_waiters));
|
|
ASSERT3P(lwb, !=, NULL);
|
|
ASSERT3S(lwb->lwb_state, !=, LWB_STATE_ISSUED);
|
|
ASSERT3S(lwb->lwb_state, !=, LWB_STATE_WRITE_DONE);
|
|
ASSERT3S(lwb->lwb_state, !=, LWB_STATE_FLUSH_DONE);
|
|
|
|
/*
|
|
* At this point, the ZIL block pointed at by the "lwb"
|
|
* variable is in one of the following states: "closed"
|
|
* or "open".
|
|
*
|
|
* If it's "closed", then no itxs have been committed to
|
|
* it, so there's no point in issuing its zio (i.e. it's
|
|
* "empty").
|
|
*
|
|
* If it's "open", then it contains one or more itxs that
|
|
* eventually need to be committed to stable storage. In
|
|
* this case we intentionally do not issue the lwb's zio
|
|
* to disk yet, and instead rely on one of the following
|
|
* two mechanisms for issuing the zio:
|
|
*
|
|
* 1. Ideally, there will be more ZIL activity occurring
|
|
* on the system, such that this function will be
|
|
* immediately called again (not necessarily by the same
|
|
* thread) and this lwb's zio will be issued via
|
|
* zil_lwb_commit(). This way, the lwb is guaranteed to
|
|
* be "full" when it is issued to disk, and we'll make
|
|
* use of the lwb's size the best we can.
|
|
*
|
|
* 2. If there isn't sufficient ZIL activity occurring on
|
|
* the system, such that this lwb's zio isn't issued via
|
|
* zil_lwb_commit(), zil_commit_waiter() will issue the
|
|
* lwb's zio. If this occurs, the lwb is not guaranteed
|
|
* to be "full" by the time its zio is issued, and means
|
|
* the size of the lwb was "too large" given the amount
|
|
* of ZIL activity occurring on the system at that time.
|
|
*
|
|
* We do this for a couple of reasons:
|
|
*
|
|
* 1. To try and reduce the number of IOPs needed to
|
|
* write the same number of itxs. If an lwb has space
|
|
* available in its buffer for more itxs, and more itxs
|
|
* will be committed relatively soon (relative to the
|
|
* latency of performing a write), then it's beneficial
|
|
* to wait for these "next" itxs. This way, more itxs
|
|
* can be committed to stable storage with fewer writes.
|
|
*
|
|
* 2. To try and use the largest lwb block size that the
|
|
* incoming rate of itxs can support. Again, this is to
|
|
* try and pack as many itxs into as few lwbs as
|
|
* possible, without significantly impacting the latency
|
|
* of each individual itx.
|
|
*/
|
|
}
|
|
}
|
|
|
|
/*
|
|
* This function is responsible for ensuring the passed in commit waiter
|
|
* (and associated commit itx) is committed to an lwb. If the waiter is
|
|
* not already committed to an lwb, all itxs in the zilog's queue of
|
|
* itxs will be processed. The assumption is the passed in waiter's
|
|
* commit itx will found in the queue just like the other non-commit
|
|
* itxs, such that when the entire queue is processed, the waiter will
|
|
* have been committed to an lwb.
|
|
*
|
|
* The lwb associated with the passed in waiter is not guaranteed to
|
|
* have been issued by the time this function completes. If the lwb is
|
|
* not issued, we rely on future calls to zil_commit_writer() to issue
|
|
* the lwb, or the timeout mechanism found in zil_commit_waiter().
|
|
*/
|
|
static void
|
|
zil_commit_writer(zilog_t *zilog, zil_commit_waiter_t *zcw)
|
|
{
|
|
ASSERT(!MUTEX_HELD(&zilog->zl_lock));
|
|
ASSERT(spa_writeable(zilog->zl_spa));
|
|
|
|
mutex_enter(&zilog->zl_issuer_lock);
|
|
|
|
if (zcw->zcw_lwb != NULL || zcw->zcw_done) {
|
|
/*
|
|
* It's possible that, while we were waiting to acquire
|
|
* the "zl_issuer_lock", another thread committed this
|
|
* waiter to an lwb. If that occurs, we bail out early,
|
|
* without processing any of the zilog's queue of itxs.
|
|
*
|
|
* On certain workloads and system configurations, the
|
|
* "zl_issuer_lock" can become highly contended. In an
|
|
* attempt to reduce this contention, we immediately drop
|
|
* the lock if the waiter has already been processed.
|
|
*
|
|
* We've measured this optimization to reduce CPU spent
|
|
* contending on this lock by up to 5%, using a system
|
|
* with 32 CPUs, low latency storage (~50 usec writes),
|
|
* and 1024 threads performing sync writes.
|
|
*/
|
|
goto out;
|
|
}
|
|
|
|
ZIL_STAT_BUMP(zil_commit_writer_count);
|
|
|
|
zil_get_commit_list(zilog);
|
|
zil_prune_commit_list(zilog);
|
|
zil_process_commit_list(zilog);
|
|
|
|
out:
|
|
mutex_exit(&zilog->zl_issuer_lock);
|
|
}
|
|
|
|
static void
|
|
zil_commit_waiter_timeout(zilog_t *zilog, zil_commit_waiter_t *zcw)
|
|
{
|
|
ASSERT(!MUTEX_HELD(&zilog->zl_issuer_lock));
|
|
ASSERT(MUTEX_HELD(&zcw->zcw_lock));
|
|
ASSERT3B(zcw->zcw_done, ==, B_FALSE);
|
|
|
|
lwb_t *lwb = zcw->zcw_lwb;
|
|
ASSERT3P(lwb, !=, NULL);
|
|
ASSERT3S(lwb->lwb_state, !=, LWB_STATE_CLOSED);
|
|
|
|
/*
|
|
* If the lwb has already been issued by another thread, we can
|
|
* immediately return since there's no work to be done (the
|
|
* point of this function is to issue the lwb). Additionally, we
|
|
* do this prior to acquiring the zl_issuer_lock, to avoid
|
|
* acquiring it when it's not necessary to do so.
|
|
*/
|
|
if (lwb->lwb_state == LWB_STATE_ISSUED ||
|
|
lwb->lwb_state == LWB_STATE_WRITE_DONE ||
|
|
lwb->lwb_state == LWB_STATE_FLUSH_DONE)
|
|
return;
|
|
|
|
/*
|
|
* In order to call zil_lwb_write_issue() we must hold the
|
|
* zilog's "zl_issuer_lock". We can't simply acquire that lock,
|
|
* since we're already holding the commit waiter's "zcw_lock",
|
|
* and those two locks are acquired in the opposite order
|
|
* elsewhere.
|
|
*/
|
|
mutex_exit(&zcw->zcw_lock);
|
|
mutex_enter(&zilog->zl_issuer_lock);
|
|
mutex_enter(&zcw->zcw_lock);
|
|
|
|
/*
|
|
* Since we just dropped and re-acquired the commit waiter's
|
|
* lock, we have to re-check to see if the waiter was marked
|
|
* "done" during that process. If the waiter was marked "done",
|
|
* the "lwb" pointer is no longer valid (it can be free'd after
|
|
* the waiter is marked "done"), so without this check we could
|
|
* wind up with a use-after-free error below.
|
|
*/
|
|
if (zcw->zcw_done)
|
|
goto out;
|
|
|
|
ASSERT3P(lwb, ==, zcw->zcw_lwb);
|
|
|
|
/*
|
|
* We've already checked this above, but since we hadn't acquired
|
|
* the zilog's zl_issuer_lock, we have to perform this check a
|
|
* second time while holding the lock.
|
|
*
|
|
* We don't need to hold the zl_lock since the lwb cannot transition
|
|
* from OPENED to ISSUED while we hold the zl_issuer_lock. The lwb
|
|
* _can_ transition from ISSUED to DONE, but it's OK to race with
|
|
* that transition since we treat the lwb the same, whether it's in
|
|
* the ISSUED or DONE states.
|
|
*
|
|
* The important thing, is we treat the lwb differently depending on
|
|
* if it's ISSUED or OPENED, and block any other threads that might
|
|
* attempt to issue this lwb. For that reason we hold the
|
|
* zl_issuer_lock when checking the lwb_state; we must not call
|
|
* zil_lwb_write_issue() if the lwb had already been issued.
|
|
*
|
|
* See the comment above the lwb_state_t structure definition for
|
|
* more details on the lwb states, and locking requirements.
|
|
*/
|
|
if (lwb->lwb_state == LWB_STATE_ISSUED ||
|
|
lwb->lwb_state == LWB_STATE_WRITE_DONE ||
|
|
lwb->lwb_state == LWB_STATE_FLUSH_DONE)
|
|
goto out;
|
|
|
|
ASSERT3S(lwb->lwb_state, ==, LWB_STATE_OPENED);
|
|
|
|
/*
|
|
* As described in the comments above zil_commit_waiter() and
|
|
* zil_process_commit_list(), we need to issue this lwb's zio
|
|
* since we've reached the commit waiter's timeout and it still
|
|
* hasn't been issued.
|
|
*/
|
|
lwb_t *nlwb = zil_lwb_write_issue(zilog, lwb);
|
|
|
|
IMPLY(nlwb != NULL, lwb->lwb_state != LWB_STATE_OPENED);
|
|
|
|
/*
|
|
* Since the lwb's zio hadn't been issued by the time this thread
|
|
* reached its timeout, we reset the zilog's "zl_cur_used" field
|
|
* to influence the zil block size selection algorithm.
|
|
*
|
|
* By having to issue the lwb's zio here, it means the size of the
|
|
* lwb was too large, given the incoming throughput of itxs. By
|
|
* setting "zl_cur_used" to zero, we communicate this fact to the
|
|
* block size selection algorithm, so it can take this information
|
|
* into account, and potentially select a smaller size for the
|
|
* next lwb block that is allocated.
|
|
*/
|
|
zilog->zl_cur_used = 0;
|
|
|
|
if (nlwb == NULL) {
|
|
/*
|
|
* When zil_lwb_write_issue() returns NULL, this
|
|
* indicates zio_alloc_zil() failed to allocate the
|
|
* "next" lwb on-disk. When this occurs, the ZIL write
|
|
* pipeline must be stalled; see the comment within the
|
|
* zil_commit_writer_stall() function for more details.
|
|
*
|
|
* We must drop the commit waiter's lock prior to
|
|
* calling zil_commit_writer_stall() or else we can wind
|
|
* up with the following deadlock:
|
|
*
|
|
* - This thread is waiting for the txg to sync while
|
|
* holding the waiter's lock; txg_wait_synced() is
|
|
* used within txg_commit_writer_stall().
|
|
*
|
|
* - The txg can't sync because it is waiting for this
|
|
* lwb's zio callback to call dmu_tx_commit().
|
|
*
|
|
* - The lwb's zio callback can't call dmu_tx_commit()
|
|
* because it's blocked trying to acquire the waiter's
|
|
* lock, which occurs prior to calling dmu_tx_commit()
|
|
*/
|
|
mutex_exit(&zcw->zcw_lock);
|
|
zil_commit_writer_stall(zilog);
|
|
mutex_enter(&zcw->zcw_lock);
|
|
}
|
|
|
|
out:
|
|
mutex_exit(&zilog->zl_issuer_lock);
|
|
ASSERT(MUTEX_HELD(&zcw->zcw_lock));
|
|
}
|
|
|
|
/*
|
|
* This function is responsible for performing the following two tasks:
|
|
*
|
|
* 1. its primary responsibility is to block until the given "commit
|
|
* waiter" is considered "done".
|
|
*
|
|
* 2. its secondary responsibility is to issue the zio for the lwb that
|
|
* the given "commit waiter" is waiting on, if this function has
|
|
* waited "long enough" and the lwb is still in the "open" state.
|
|
*
|
|
* Given a sufficient amount of itxs being generated and written using
|
|
* the ZIL, the lwb's zio will be issued via the zil_lwb_commit()
|
|
* function. If this does not occur, this secondary responsibility will
|
|
* ensure the lwb is issued even if there is not other synchronous
|
|
* activity on the system.
|
|
*
|
|
* For more details, see zil_process_commit_list(); more specifically,
|
|
* the comment at the bottom of that function.
|
|
*/
|
|
static void
|
|
zil_commit_waiter(zilog_t *zilog, zil_commit_waiter_t *zcw)
|
|
{
|
|
ASSERT(!MUTEX_HELD(&zilog->zl_lock));
|
|
ASSERT(!MUTEX_HELD(&zilog->zl_issuer_lock));
|
|
ASSERT(spa_writeable(zilog->zl_spa));
|
|
|
|
mutex_enter(&zcw->zcw_lock);
|
|
|
|
/*
|
|
* The timeout is scaled based on the lwb latency to avoid
|
|
* significantly impacting the latency of each individual itx.
|
|
* For more details, see the comment at the bottom of the
|
|
* zil_process_commit_list() function.
|
|
*/
|
|
int pct = MAX(zfs_commit_timeout_pct, 1);
|
|
hrtime_t sleep = (zilog->zl_last_lwb_latency * pct) / 100;
|
|
hrtime_t wakeup = gethrtime() + sleep;
|
|
boolean_t timedout = B_FALSE;
|
|
|
|
while (!zcw->zcw_done) {
|
|
ASSERT(MUTEX_HELD(&zcw->zcw_lock));
|
|
|
|
lwb_t *lwb = zcw->zcw_lwb;
|
|
|
|
/*
|
|
* Usually, the waiter will have a non-NULL lwb field here,
|
|
* but it's possible for it to be NULL as a result of
|
|
* zil_commit() racing with spa_sync().
|
|
*
|
|
* When zil_clean() is called, it's possible for the itxg
|
|
* list (which may be cleaned via a taskq) to contain
|
|
* commit itxs. When this occurs, the commit waiters linked
|
|
* off of these commit itxs will not be committed to an
|
|
* lwb. Additionally, these commit waiters will not be
|
|
* marked done until zil_commit_waiter_skip() is called via
|
|
* zil_itxg_clean().
|
|
*
|
|
* Thus, it's possible for this commit waiter (i.e. the
|
|
* "zcw" variable) to be found in this "in between" state;
|
|
* where it's "zcw_lwb" field is NULL, and it hasn't yet
|
|
* been skipped, so it's "zcw_done" field is still B_FALSE.
|
|
*/
|
|
IMPLY(lwb != NULL, lwb->lwb_state != LWB_STATE_CLOSED);
|
|
|
|
if (lwb != NULL && lwb->lwb_state == LWB_STATE_OPENED) {
|
|
ASSERT3B(timedout, ==, B_FALSE);
|
|
|
|
/*
|
|
* If the lwb hasn't been issued yet, then we
|
|
* need to wait with a timeout, in case this
|
|
* function needs to issue the lwb after the
|
|
* timeout is reached; responsibility (2) from
|
|
* the comment above this function.
|
|
*/
|
|
int rc = cv_timedwait_hires(&zcw->zcw_cv,
|
|
&zcw->zcw_lock, wakeup, USEC2NSEC(1),
|
|
CALLOUT_FLAG_ABSOLUTE);
|
|
|
|
if (rc != -1 || zcw->zcw_done)
|
|
continue;
|
|
|
|
timedout = B_TRUE;
|
|
zil_commit_waiter_timeout(zilog, zcw);
|
|
|
|
if (!zcw->zcw_done) {
|
|
/*
|
|
* If the commit waiter has already been
|
|
* marked "done", it's possible for the
|
|
* waiter's lwb structure to have already
|
|
* been freed. Thus, we can only reliably
|
|
* make these assertions if the waiter
|
|
* isn't done.
|
|
*/
|
|
ASSERT3P(lwb, ==, zcw->zcw_lwb);
|
|
ASSERT3S(lwb->lwb_state, !=, LWB_STATE_OPENED);
|
|
}
|
|
} else {
|
|
/*
|
|
* If the lwb isn't open, then it must have already
|
|
* been issued. In that case, there's no need to
|
|
* use a timeout when waiting for the lwb to
|
|
* complete.
|
|
*
|
|
* Additionally, if the lwb is NULL, the waiter
|
|
* will soon be signaled and marked done via
|
|
* zil_clean() and zil_itxg_clean(), so no timeout
|
|
* is required.
|
|
*/
|
|
|
|
IMPLY(lwb != NULL,
|
|
lwb->lwb_state == LWB_STATE_ISSUED ||
|
|
lwb->lwb_state == LWB_STATE_WRITE_DONE ||
|
|
lwb->lwb_state == LWB_STATE_FLUSH_DONE);
|
|
cv_wait(&zcw->zcw_cv, &zcw->zcw_lock);
|
|
}
|
|
}
|
|
|
|
mutex_exit(&zcw->zcw_lock);
|
|
}
|
|
|
|
static zil_commit_waiter_t *
|
|
zil_alloc_commit_waiter(void)
|
|
{
|
|
zil_commit_waiter_t *zcw = kmem_cache_alloc(zil_zcw_cache, KM_SLEEP);
|
|
|
|
cv_init(&zcw->zcw_cv, NULL, CV_DEFAULT, NULL);
|
|
mutex_init(&zcw->zcw_lock, NULL, MUTEX_DEFAULT, NULL);
|
|
list_link_init(&zcw->zcw_node);
|
|
zcw->zcw_lwb = NULL;
|
|
zcw->zcw_done = B_FALSE;
|
|
zcw->zcw_zio_error = 0;
|
|
|
|
return (zcw);
|
|
}
|
|
|
|
static void
|
|
zil_free_commit_waiter(zil_commit_waiter_t *zcw)
|
|
{
|
|
ASSERT(!list_link_active(&zcw->zcw_node));
|
|
ASSERT3P(zcw->zcw_lwb, ==, NULL);
|
|
ASSERT3B(zcw->zcw_done, ==, B_TRUE);
|
|
mutex_destroy(&zcw->zcw_lock);
|
|
cv_destroy(&zcw->zcw_cv);
|
|
kmem_cache_free(zil_zcw_cache, zcw);
|
|
}
|
|
|
|
/*
|
|
* This function is used to create a TX_COMMIT itx and assign it. This
|
|
* way, it will be linked into the ZIL's list of synchronous itxs, and
|
|
* then later committed to an lwb (or skipped) when
|
|
* zil_process_commit_list() is called.
|
|
*/
|
|
static void
|
|
zil_commit_itx_assign(zilog_t *zilog, zil_commit_waiter_t *zcw)
|
|
{
|
|
dmu_tx_t *tx = dmu_tx_create(zilog->zl_os);
|
|
VERIFY0(dmu_tx_assign(tx, TXG_WAIT));
|
|
|
|
itx_t *itx = zil_itx_create(TX_COMMIT, sizeof (lr_t));
|
|
itx->itx_sync = B_TRUE;
|
|
itx->itx_private = zcw;
|
|
|
|
zil_itx_assign(zilog, itx, tx);
|
|
|
|
dmu_tx_commit(tx);
|
|
}
|
|
|
|
/*
|
|
* Commit ZFS Intent Log transactions (itxs) to stable storage.
|
|
*
|
|
* When writing ZIL transactions to the on-disk representation of the
|
|
* ZIL, the itxs are committed to a Log Write Block (lwb). Multiple
|
|
* itxs can be committed to a single lwb. Once a lwb is written and
|
|
* committed to stable storage (i.e. the lwb is written, and vdevs have
|
|
* been flushed), each itx that was committed to that lwb is also
|
|
* considered to be committed to stable storage.
|
|
*
|
|
* When an itx is committed to an lwb, the log record (lr_t) contained
|
|
* by the itx is copied into the lwb's zio buffer, and once this buffer
|
|
* is written to disk, it becomes an on-disk ZIL block.
|
|
*
|
|
* As itxs are generated, they're inserted into the ZIL's queue of
|
|
* uncommitted itxs. The semantics of zil_commit() are such that it will
|
|
* block until all itxs that were in the queue when it was called, are
|
|
* committed to stable storage.
|
|
*
|
|
* If "foid" is zero, this means all "synchronous" and "asynchronous"
|
|
* itxs, for all objects in the dataset, will be committed to stable
|
|
* storage prior to zil_commit() returning. If "foid" is non-zero, all
|
|
* "synchronous" itxs for all objects, but only "asynchronous" itxs
|
|
* that correspond to the foid passed in, will be committed to stable
|
|
* storage prior to zil_commit() returning.
|
|
*
|
|
* Generally speaking, when zil_commit() is called, the consumer doesn't
|
|
* actually care about _all_ of the uncommitted itxs. Instead, they're
|
|
* simply trying to waiting for a specific itx to be committed to disk,
|
|
* but the interface(s) for interacting with the ZIL don't allow such
|
|
* fine-grained communication. A better interface would allow a consumer
|
|
* to create and assign an itx, and then pass a reference to this itx to
|
|
* zil_commit(); such that zil_commit() would return as soon as that
|
|
* specific itx was committed to disk (instead of waiting for _all_
|
|
* itxs to be committed).
|
|
*
|
|
* When a thread calls zil_commit() a special "commit itx" will be
|
|
* generated, along with a corresponding "waiter" for this commit itx.
|
|
* zil_commit() will wait on this waiter's CV, such that when the waiter
|
|
* is marked done, and signaled, zil_commit() will return.
|
|
*
|
|
* This commit itx is inserted into the queue of uncommitted itxs. This
|
|
* provides an easy mechanism for determining which itxs were in the
|
|
* queue prior to zil_commit() having been called, and which itxs were
|
|
* added after zil_commit() was called.
|
|
*
|
|
* The commit it is special; it doesn't have any on-disk representation.
|
|
* When a commit itx is "committed" to an lwb, the waiter associated
|
|
* with it is linked onto the lwb's list of waiters. Then, when that lwb
|
|
* completes, each waiter on the lwb's list is marked done and signaled
|
|
* -- allowing the thread waiting on the waiter to return from zil_commit().
|
|
*
|
|
* It's important to point out a few critical factors that allow us
|
|
* to make use of the commit itxs, commit waiters, per-lwb lists of
|
|
* commit waiters, and zio completion callbacks like we're doing:
|
|
*
|
|
* 1. The list of waiters for each lwb is traversed, and each commit
|
|
* waiter is marked "done" and signaled, in the zio completion
|
|
* callback of the lwb's zio[*].
|
|
*
|
|
* * Actually, the waiters are signaled in the zio completion
|
|
* callback of the root zio for the DKIOCFLUSHWRITECACHE commands
|
|
* that are sent to the vdevs upon completion of the lwb zio.
|
|
*
|
|
* 2. When the itxs are inserted into the ZIL's queue of uncommitted
|
|
* itxs, the order in which they are inserted is preserved[*]; as
|
|
* itxs are added to the queue, they are added to the tail of
|
|
* in-memory linked lists.
|
|
*
|
|
* When committing the itxs to lwbs (to be written to disk), they
|
|
* are committed in the same order in which the itxs were added to
|
|
* the uncommitted queue's linked list(s); i.e. the linked list of
|
|
* itxs to commit is traversed from head to tail, and each itx is
|
|
* committed to an lwb in that order.
|
|
*
|
|
* * To clarify:
|
|
*
|
|
* - the order of "sync" itxs is preserved w.r.t. other
|
|
* "sync" itxs, regardless of the corresponding objects.
|
|
* - the order of "async" itxs is preserved w.r.t. other
|
|
* "async" itxs corresponding to the same object.
|
|
* - the order of "async" itxs is *not* preserved w.r.t. other
|
|
* "async" itxs corresponding to different objects.
|
|
* - the order of "sync" itxs w.r.t. "async" itxs (or vice
|
|
* versa) is *not* preserved, even for itxs that correspond
|
|
* to the same object.
|
|
*
|
|
* For more details, see: zil_itx_assign(), zil_async_to_sync(),
|
|
* zil_get_commit_list(), and zil_process_commit_list().
|
|
*
|
|
* 3. The lwbs represent a linked list of blocks on disk. Thus, any
|
|
* lwb cannot be considered committed to stable storage, until its
|
|
* "previous" lwb is also committed to stable storage. This fact,
|
|
* coupled with the fact described above, means that itxs are
|
|
* committed in (roughly) the order in which they were generated.
|
|
* This is essential because itxs are dependent on prior itxs.
|
|
* Thus, we *must not* deem an itx as being committed to stable
|
|
* storage, until *all* prior itxs have also been committed to
|
|
* stable storage.
|
|
*
|
|
* To enforce this ordering of lwb zio's, while still leveraging as
|
|
* much of the underlying storage performance as possible, we rely
|
|
* on two fundamental concepts:
|
|
*
|
|
* 1. The creation and issuance of lwb zio's is protected by
|
|
* the zilog's "zl_issuer_lock", which ensures only a single
|
|
* thread is creating and/or issuing lwb's at a time
|
|
* 2. The "previous" lwb is a child of the "current" lwb
|
|
* (leveraging the zio parent-child dependency graph)
|
|
*
|
|
* By relying on this parent-child zio relationship, we can have
|
|
* many lwb zio's concurrently issued to the underlying storage,
|
|
* but the order in which they complete will be the same order in
|
|
* which they were created.
|
|
*/
|
|
void
|
|
zil_commit(zilog_t *zilog, uint64_t foid)
|
|
{
|
|
/*
|
|
* We should never attempt to call zil_commit on a snapshot for
|
|
* a couple of reasons:
|
|
*
|
|
* 1. A snapshot may never be modified, thus it cannot have any
|
|
* in-flight itxs that would have modified the dataset.
|
|
*
|
|
* 2. By design, when zil_commit() is called, a commit itx will
|
|
* be assigned to this zilog; as a result, the zilog will be
|
|
* dirtied. We must not dirty the zilog of a snapshot; there's
|
|
* checks in the code that enforce this invariant, and will
|
|
* cause a panic if it's not upheld.
|
|
*/
|
|
ASSERT3B(dmu_objset_is_snapshot(zilog->zl_os), ==, B_FALSE);
|
|
|
|
if (zilog->zl_sync == ZFS_SYNC_DISABLED)
|
|
return;
|
|
|
|
if (!spa_writeable(zilog->zl_spa)) {
|
|
/*
|
|
* If the SPA is not writable, there should never be any
|
|
* pending itxs waiting to be committed to disk. If that
|
|
* weren't true, we'd skip writing those itxs out, and
|
|
* would break the semantics of zil_commit(); thus, we're
|
|
* verifying that truth before we return to the caller.
|
|
*/
|
|
ASSERT(list_is_empty(&zilog->zl_lwb_list));
|
|
ASSERT3P(zilog->zl_last_lwb_opened, ==, NULL);
|
|
for (int i = 0; i < TXG_SIZE; i++)
|
|
ASSERT3P(zilog->zl_itxg[i].itxg_itxs, ==, NULL);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* If the ZIL is suspended, we don't want to dirty it by calling
|
|
* zil_commit_itx_assign() below, nor can we write out
|
|
* lwbs like would be done in zil_commit_write(). Thus, we
|
|
* simply rely on txg_wait_synced() to maintain the necessary
|
|
* semantics, and avoid calling those functions altogether.
|
|
*/
|
|
if (zilog->zl_suspend > 0) {
|
|
txg_wait_synced(zilog->zl_dmu_pool, 0);
|
|
return;
|
|
}
|
|
|
|
zil_commit_impl(zilog, foid);
|
|
}
|
|
|
|
void
|
|
zil_commit_impl(zilog_t *zilog, uint64_t foid)
|
|
{
|
|
ZIL_STAT_BUMP(zil_commit_count);
|
|
|
|
/*
|
|
* Move the "async" itxs for the specified foid to the "sync"
|
|
* queues, such that they will be later committed (or skipped)
|
|
* to an lwb when zil_process_commit_list() is called.
|
|
*
|
|
* Since these "async" itxs must be committed prior to this
|
|
* call to zil_commit returning, we must perform this operation
|
|
* before we call zil_commit_itx_assign().
|
|
*/
|
|
zil_async_to_sync(zilog, foid);
|
|
|
|
/*
|
|
* We allocate a new "waiter" structure which will initially be
|
|
* linked to the commit itx using the itx's "itx_private" field.
|
|
* Since the commit itx doesn't represent any on-disk state,
|
|
* when it's committed to an lwb, rather than copying the its
|
|
* lr_t into the lwb's buffer, the commit itx's "waiter" will be
|
|
* added to the lwb's list of waiters. Then, when the lwb is
|
|
* committed to stable storage, each waiter in the lwb's list of
|
|
* waiters will be marked "done", and signalled.
|
|
*
|
|
* We must create the waiter and assign the commit itx prior to
|
|
* calling zil_commit_writer(), or else our specific commit itx
|
|
* is not guaranteed to be committed to an lwb prior to calling
|
|
* zil_commit_waiter().
|
|
*/
|
|
zil_commit_waiter_t *zcw = zil_alloc_commit_waiter();
|
|
zil_commit_itx_assign(zilog, zcw);
|
|
|
|
zil_commit_writer(zilog, zcw);
|
|
zil_commit_waiter(zilog, zcw);
|
|
|
|
if (zcw->zcw_zio_error != 0) {
|
|
/*
|
|
* If there was an error writing out the ZIL blocks that
|
|
* this thread is waiting on, then we fallback to
|
|
* relying on spa_sync() to write out the data this
|
|
* thread is waiting on. Obviously this has performance
|
|
* implications, but the expectation is for this to be
|
|
* an exceptional case, and shouldn't occur often.
|
|
*/
|
|
DTRACE_PROBE2(zil__commit__io__error,
|
|
zilog_t *, zilog, zil_commit_waiter_t *, zcw);
|
|
txg_wait_synced(zilog->zl_dmu_pool, 0);
|
|
}
|
|
|
|
zil_free_commit_waiter(zcw);
|
|
}
|
|
|
|
/*
|
|
* Called in syncing context to free committed log blocks and update log header.
|
|
*/
|
|
void
|
|
zil_sync(zilog_t *zilog, dmu_tx_t *tx)
|
|
{
|
|
zil_header_t *zh = zil_header_in_syncing_context(zilog);
|
|
uint64_t txg = dmu_tx_get_txg(tx);
|
|
spa_t *spa = zilog->zl_spa;
|
|
uint64_t *replayed_seq = &zilog->zl_replayed_seq[txg & TXG_MASK];
|
|
lwb_t *lwb;
|
|
|
|
/*
|
|
* We don't zero out zl_destroy_txg, so make sure we don't try
|
|
* to destroy it twice.
|
|
*/
|
|
if (spa_sync_pass(spa) != 1)
|
|
return;
|
|
|
|
mutex_enter(&zilog->zl_lock);
|
|
|
|
ASSERT(zilog->zl_stop_sync == 0);
|
|
|
|
if (*replayed_seq != 0) {
|
|
ASSERT(zh->zh_replay_seq < *replayed_seq);
|
|
zh->zh_replay_seq = *replayed_seq;
|
|
*replayed_seq = 0;
|
|
}
|
|
|
|
if (zilog->zl_destroy_txg == txg) {
|
|
blkptr_t blk = zh->zh_log;
|
|
|
|
ASSERT(list_head(&zilog->zl_lwb_list) == NULL);
|
|
|
|
bzero(zh, sizeof (zil_header_t));
|
|
bzero(zilog->zl_replayed_seq, sizeof (zilog->zl_replayed_seq));
|
|
|
|
if (zilog->zl_keep_first) {
|
|
/*
|
|
* If this block was part of log chain that couldn't
|
|
* be claimed because a device was missing during
|
|
* zil_claim(), but that device later returns,
|
|
* then this block could erroneously appear valid.
|
|
* To guard against this, assign a new GUID to the new
|
|
* log chain so it doesn't matter what blk points to.
|
|
*/
|
|
zil_init_log_chain(zilog, &blk);
|
|
zh->zh_log = blk;
|
|
}
|
|
}
|
|
|
|
while ((lwb = list_head(&zilog->zl_lwb_list)) != NULL) {
|
|
zh->zh_log = lwb->lwb_blk;
|
|
if (lwb->lwb_buf != NULL || lwb->lwb_max_txg > txg)
|
|
break;
|
|
list_remove(&zilog->zl_lwb_list, lwb);
|
|
zio_free(spa, txg, &lwb->lwb_blk);
|
|
zil_free_lwb(zilog, lwb);
|
|
|
|
/*
|
|
* If we don't have anything left in the lwb list then
|
|
* we've had an allocation failure and we need to zero
|
|
* out the zil_header blkptr so that we don't end
|
|
* up freeing the same block twice.
|
|
*/
|
|
if (list_head(&zilog->zl_lwb_list) == NULL)
|
|
BP_ZERO(&zh->zh_log);
|
|
}
|
|
|
|
/*
|
|
* Remove fastwrite on any blocks that have been pre-allocated for
|
|
* the next commit. This prevents fastwrite counter pollution by
|
|
* unused, long-lived LWBs.
|
|
*/
|
|
for (; lwb != NULL; lwb = list_next(&zilog->zl_lwb_list, lwb)) {
|
|
if (lwb->lwb_fastwrite && !lwb->lwb_write_zio) {
|
|
metaslab_fastwrite_unmark(zilog->zl_spa, &lwb->lwb_blk);
|
|
lwb->lwb_fastwrite = 0;
|
|
}
|
|
}
|
|
|
|
mutex_exit(&zilog->zl_lock);
|
|
}
|
|
|
|
/* ARGSUSED */
|
|
static int
|
|
zil_lwb_cons(void *vbuf, void *unused, int kmflag)
|
|
{
|
|
lwb_t *lwb = vbuf;
|
|
list_create(&lwb->lwb_itxs, sizeof (itx_t), offsetof(itx_t, itx_node));
|
|
list_create(&lwb->lwb_waiters, sizeof (zil_commit_waiter_t),
|
|
offsetof(zil_commit_waiter_t, zcw_node));
|
|
avl_create(&lwb->lwb_vdev_tree, zil_lwb_vdev_compare,
|
|
sizeof (zil_vdev_node_t), offsetof(zil_vdev_node_t, zv_node));
|
|
mutex_init(&lwb->lwb_vdev_lock, NULL, MUTEX_DEFAULT, NULL);
|
|
return (0);
|
|
}
|
|
|
|
/* ARGSUSED */
|
|
static void
|
|
zil_lwb_dest(void *vbuf, void *unused)
|
|
{
|
|
lwb_t *lwb = vbuf;
|
|
mutex_destroy(&lwb->lwb_vdev_lock);
|
|
avl_destroy(&lwb->lwb_vdev_tree);
|
|
list_destroy(&lwb->lwb_waiters);
|
|
list_destroy(&lwb->lwb_itxs);
|
|
}
|
|
|
|
void
|
|
zil_init(void)
|
|
{
|
|
zil_lwb_cache = kmem_cache_create("zil_lwb_cache",
|
|
sizeof (lwb_t), 0, zil_lwb_cons, zil_lwb_dest, NULL, NULL, NULL, 0);
|
|
|
|
zil_zcw_cache = kmem_cache_create("zil_zcw_cache",
|
|
sizeof (zil_commit_waiter_t), 0, NULL, NULL, NULL, NULL, NULL, 0);
|
|
|
|
zil_ksp = kstat_create("zfs", 0, "zil", "misc",
|
|
KSTAT_TYPE_NAMED, sizeof (zil_stats) / sizeof (kstat_named_t),
|
|
KSTAT_FLAG_VIRTUAL);
|
|
|
|
if (zil_ksp != NULL) {
|
|
zil_ksp->ks_data = &zil_stats;
|
|
kstat_install(zil_ksp);
|
|
}
|
|
}
|
|
|
|
void
|
|
zil_fini(void)
|
|
{
|
|
kmem_cache_destroy(zil_zcw_cache);
|
|
kmem_cache_destroy(zil_lwb_cache);
|
|
|
|
if (zil_ksp != NULL) {
|
|
kstat_delete(zil_ksp);
|
|
zil_ksp = NULL;
|
|
}
|
|
}
|
|
|
|
void
|
|
zil_set_sync(zilog_t *zilog, uint64_t sync)
|
|
{
|
|
zilog->zl_sync = sync;
|
|
}
|
|
|
|
void
|
|
zil_set_logbias(zilog_t *zilog, uint64_t logbias)
|
|
{
|
|
zilog->zl_logbias = logbias;
|
|
}
|
|
|
|
zilog_t *
|
|
zil_alloc(objset_t *os, zil_header_t *zh_phys)
|
|
{
|
|
zilog_t *zilog;
|
|
|
|
zilog = kmem_zalloc(sizeof (zilog_t), KM_SLEEP);
|
|
|
|
zilog->zl_header = zh_phys;
|
|
zilog->zl_os = os;
|
|
zilog->zl_spa = dmu_objset_spa(os);
|
|
zilog->zl_dmu_pool = dmu_objset_pool(os);
|
|
zilog->zl_destroy_txg = TXG_INITIAL - 1;
|
|
zilog->zl_logbias = dmu_objset_logbias(os);
|
|
zilog->zl_sync = dmu_objset_syncprop(os);
|
|
zilog->zl_dirty_max_txg = 0;
|
|
zilog->zl_last_lwb_opened = NULL;
|
|
zilog->zl_last_lwb_latency = 0;
|
|
zilog->zl_max_block_size = zil_maxblocksize;
|
|
|
|
mutex_init(&zilog->zl_lock, NULL, MUTEX_DEFAULT, NULL);
|
|
mutex_init(&zilog->zl_issuer_lock, NULL, MUTEX_DEFAULT, NULL);
|
|
|
|
for (int i = 0; i < TXG_SIZE; i++) {
|
|
mutex_init(&zilog->zl_itxg[i].itxg_lock, NULL,
|
|
MUTEX_DEFAULT, NULL);
|
|
}
|
|
|
|
list_create(&zilog->zl_lwb_list, sizeof (lwb_t),
|
|
offsetof(lwb_t, lwb_node));
|
|
|
|
list_create(&zilog->zl_itx_commit_list, sizeof (itx_t),
|
|
offsetof(itx_t, itx_node));
|
|
|
|
cv_init(&zilog->zl_cv_suspend, NULL, CV_DEFAULT, NULL);
|
|
|
|
return (zilog);
|
|
}
|
|
|
|
void
|
|
zil_free(zilog_t *zilog)
|
|
{
|
|
int i;
|
|
|
|
zilog->zl_stop_sync = 1;
|
|
|
|
ASSERT0(zilog->zl_suspend);
|
|
ASSERT0(zilog->zl_suspending);
|
|
|
|
ASSERT(list_is_empty(&zilog->zl_lwb_list));
|
|
list_destroy(&zilog->zl_lwb_list);
|
|
|
|
ASSERT(list_is_empty(&zilog->zl_itx_commit_list));
|
|
list_destroy(&zilog->zl_itx_commit_list);
|
|
|
|
for (i = 0; i < TXG_SIZE; i++) {
|
|
/*
|
|
* It's possible for an itx to be generated that doesn't dirty
|
|
* a txg (e.g. ztest TX_TRUNCATE). So there's no zil_clean()
|
|
* callback to remove the entry. We remove those here.
|
|
*
|
|
* Also free up the ziltest itxs.
|
|
*/
|
|
if (zilog->zl_itxg[i].itxg_itxs)
|
|
zil_itxg_clean(zilog->zl_itxg[i].itxg_itxs);
|
|
mutex_destroy(&zilog->zl_itxg[i].itxg_lock);
|
|
}
|
|
|
|
mutex_destroy(&zilog->zl_issuer_lock);
|
|
mutex_destroy(&zilog->zl_lock);
|
|
|
|
cv_destroy(&zilog->zl_cv_suspend);
|
|
|
|
kmem_free(zilog, sizeof (zilog_t));
|
|
}
|
|
|
|
/*
|
|
* Open an intent log.
|
|
*/
|
|
zilog_t *
|
|
zil_open(objset_t *os, zil_get_data_t *get_data)
|
|
{
|
|
zilog_t *zilog = dmu_objset_zil(os);
|
|
|
|
ASSERT3P(zilog->zl_get_data, ==, NULL);
|
|
ASSERT3P(zilog->zl_last_lwb_opened, ==, NULL);
|
|
ASSERT(list_is_empty(&zilog->zl_lwb_list));
|
|
|
|
zilog->zl_get_data = get_data;
|
|
|
|
return (zilog);
|
|
}
|
|
|
|
/*
|
|
* Close an intent log.
|
|
*/
|
|
void
|
|
zil_close(zilog_t *zilog)
|
|
{
|
|
lwb_t *lwb;
|
|
uint64_t txg;
|
|
|
|
if (!dmu_objset_is_snapshot(zilog->zl_os)) {
|
|
zil_commit(zilog, 0);
|
|
} else {
|
|
ASSERT3P(list_tail(&zilog->zl_lwb_list), ==, NULL);
|
|
ASSERT0(zilog->zl_dirty_max_txg);
|
|
ASSERT3B(zilog_is_dirty(zilog), ==, B_FALSE);
|
|
}
|
|
|
|
mutex_enter(&zilog->zl_lock);
|
|
lwb = list_tail(&zilog->zl_lwb_list);
|
|
if (lwb == NULL)
|
|
txg = zilog->zl_dirty_max_txg;
|
|
else
|
|
txg = MAX(zilog->zl_dirty_max_txg, lwb->lwb_max_txg);
|
|
mutex_exit(&zilog->zl_lock);
|
|
|
|
/*
|
|
* We need to use txg_wait_synced() to wait long enough for the
|
|
* ZIL to be clean, and to wait for all pending lwbs to be
|
|
* written out.
|
|
*/
|
|
if (txg != 0)
|
|
txg_wait_synced(zilog->zl_dmu_pool, txg);
|
|
|
|
if (zilog_is_dirty(zilog))
|
|
zfs_dbgmsg("zil (%px) is dirty, txg %llu", zilog, txg);
|
|
if (txg < spa_freeze_txg(zilog->zl_spa))
|
|
VERIFY(!zilog_is_dirty(zilog));
|
|
|
|
zilog->zl_get_data = NULL;
|
|
|
|
/*
|
|
* We should have only one lwb left on the list; remove it now.
|
|
*/
|
|
mutex_enter(&zilog->zl_lock);
|
|
lwb = list_head(&zilog->zl_lwb_list);
|
|
if (lwb != NULL) {
|
|
ASSERT3P(lwb, ==, list_tail(&zilog->zl_lwb_list));
|
|
ASSERT3S(lwb->lwb_state, !=, LWB_STATE_ISSUED);
|
|
|
|
if (lwb->lwb_fastwrite)
|
|
metaslab_fastwrite_unmark(zilog->zl_spa, &lwb->lwb_blk);
|
|
|
|
list_remove(&zilog->zl_lwb_list, lwb);
|
|
zio_buf_free(lwb->lwb_buf, lwb->lwb_sz);
|
|
zil_free_lwb(zilog, lwb);
|
|
}
|
|
mutex_exit(&zilog->zl_lock);
|
|
}
|
|
|
|
static char *suspend_tag = "zil suspending";
|
|
|
|
/*
|
|
* Suspend an intent log. While in suspended mode, we still honor
|
|
* synchronous semantics, but we rely on txg_wait_synced() to do it.
|
|
* On old version pools, we suspend the log briefly when taking a
|
|
* snapshot so that it will have an empty intent log.
|
|
*
|
|
* Long holds are not really intended to be used the way we do here --
|
|
* held for such a short time. A concurrent caller of dsl_dataset_long_held()
|
|
* could fail. Therefore we take pains to only put a long hold if it is
|
|
* actually necessary. Fortunately, it will only be necessary if the
|
|
* objset is currently mounted (or the ZVOL equivalent). In that case it
|
|
* will already have a long hold, so we are not really making things any worse.
|
|
*
|
|
* Ideally, we would locate the existing long-holder (i.e. the zfsvfs_t or
|
|
* zvol_state_t), and use their mechanism to prevent their hold from being
|
|
* dropped (e.g. VFS_HOLD()). However, that would be even more pain for
|
|
* very little gain.
|
|
*
|
|
* if cookiep == NULL, this does both the suspend & resume.
|
|
* Otherwise, it returns with the dataset "long held", and the cookie
|
|
* should be passed into zil_resume().
|
|
*/
|
|
int
|
|
zil_suspend(const char *osname, void **cookiep)
|
|
{
|
|
objset_t *os;
|
|
zilog_t *zilog;
|
|
const zil_header_t *zh;
|
|
int error;
|
|
|
|
error = dmu_objset_hold(osname, suspend_tag, &os);
|
|
if (error != 0)
|
|
return (error);
|
|
zilog = dmu_objset_zil(os);
|
|
|
|
mutex_enter(&zilog->zl_lock);
|
|
zh = zilog->zl_header;
|
|
|
|
if (zh->zh_flags & ZIL_REPLAY_NEEDED) { /* unplayed log */
|
|
mutex_exit(&zilog->zl_lock);
|
|
dmu_objset_rele(os, suspend_tag);
|
|
return (SET_ERROR(EBUSY));
|
|
}
|
|
|
|
/*
|
|
* Don't put a long hold in the cases where we can avoid it. This
|
|
* is when there is no cookie so we are doing a suspend & resume
|
|
* (i.e. called from zil_vdev_offline()), and there's nothing to do
|
|
* for the suspend because it's already suspended, or there's no ZIL.
|
|
*/
|
|
if (cookiep == NULL && !zilog->zl_suspending &&
|
|
(zilog->zl_suspend > 0 || BP_IS_HOLE(&zh->zh_log))) {
|
|
mutex_exit(&zilog->zl_lock);
|
|
dmu_objset_rele(os, suspend_tag);
|
|
return (0);
|
|
}
|
|
|
|
dsl_dataset_long_hold(dmu_objset_ds(os), suspend_tag);
|
|
dsl_pool_rele(dmu_objset_pool(os), suspend_tag);
|
|
|
|
zilog->zl_suspend++;
|
|
|
|
if (zilog->zl_suspend > 1) {
|
|
/*
|
|
* Someone else is already suspending it.
|
|
* Just wait for them to finish.
|
|
*/
|
|
|
|
while (zilog->zl_suspending)
|
|
cv_wait(&zilog->zl_cv_suspend, &zilog->zl_lock);
|
|
mutex_exit(&zilog->zl_lock);
|
|
|
|
if (cookiep == NULL)
|
|
zil_resume(os);
|
|
else
|
|
*cookiep = os;
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* If there is no pointer to an on-disk block, this ZIL must not
|
|
* be active (e.g. filesystem not mounted), so there's nothing
|
|
* to clean up.
|
|
*/
|
|
if (BP_IS_HOLE(&zh->zh_log)) {
|
|
ASSERT(cookiep != NULL); /* fast path already handled */
|
|
|
|
*cookiep = os;
|
|
mutex_exit(&zilog->zl_lock);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* The ZIL has work to do. Ensure that the associated encryption
|
|
* key will remain mapped while we are committing the log by
|
|
* grabbing a reference to it. If the key isn't loaded we have no
|
|
* choice but to return an error until the wrapping key is loaded.
|
|
*/
|
|
if (os->os_encrypted &&
|
|
dsl_dataset_create_key_mapping(dmu_objset_ds(os)) != 0) {
|
|
zilog->zl_suspend--;
|
|
mutex_exit(&zilog->zl_lock);
|
|
dsl_dataset_long_rele(dmu_objset_ds(os), suspend_tag);
|
|
dsl_dataset_rele(dmu_objset_ds(os), suspend_tag);
|
|
return (SET_ERROR(EACCES));
|
|
}
|
|
|
|
zilog->zl_suspending = B_TRUE;
|
|
mutex_exit(&zilog->zl_lock);
|
|
|
|
/*
|
|
* We need to use zil_commit_impl to ensure we wait for all
|
|
* LWB_STATE_OPENED and LWB_STATE_ISSUED lwbs to be committed
|
|
* to disk before proceeding. If we used zil_commit instead, it
|
|
* would just call txg_wait_synced(), because zl_suspend is set.
|
|
* txg_wait_synced() doesn't wait for these lwb's to be
|
|
* LWB_STATE_FLUSH_DONE before returning.
|
|
*/
|
|
zil_commit_impl(zilog, 0);
|
|
|
|
/*
|
|
* Now that we've ensured all lwb's are LWB_STATE_FLUSH_DONE, we
|
|
* use txg_wait_synced() to ensure the data from the zilog has
|
|
* migrated to the main pool before calling zil_destroy().
|
|
*/
|
|
txg_wait_synced(zilog->zl_dmu_pool, 0);
|
|
|
|
zil_destroy(zilog, B_FALSE);
|
|
|
|
mutex_enter(&zilog->zl_lock);
|
|
zilog->zl_suspending = B_FALSE;
|
|
cv_broadcast(&zilog->zl_cv_suspend);
|
|
mutex_exit(&zilog->zl_lock);
|
|
|
|
if (os->os_encrypted)
|
|
dsl_dataset_remove_key_mapping(dmu_objset_ds(os));
|
|
|
|
if (cookiep == NULL)
|
|
zil_resume(os);
|
|
else
|
|
*cookiep = os;
|
|
return (0);
|
|
}
|
|
|
|
void
|
|
zil_resume(void *cookie)
|
|
{
|
|
objset_t *os = cookie;
|
|
zilog_t *zilog = dmu_objset_zil(os);
|
|
|
|
mutex_enter(&zilog->zl_lock);
|
|
ASSERT(zilog->zl_suspend != 0);
|
|
zilog->zl_suspend--;
|
|
mutex_exit(&zilog->zl_lock);
|
|
dsl_dataset_long_rele(dmu_objset_ds(os), suspend_tag);
|
|
dsl_dataset_rele(dmu_objset_ds(os), suspend_tag);
|
|
}
|
|
|
|
typedef struct zil_replay_arg {
|
|
zil_replay_func_t **zr_replay;
|
|
void *zr_arg;
|
|
boolean_t zr_byteswap;
|
|
char *zr_lr;
|
|
} zil_replay_arg_t;
|
|
|
|
static int
|
|
zil_replay_error(zilog_t *zilog, const lr_t *lr, int error)
|
|
{
|
|
char name[ZFS_MAX_DATASET_NAME_LEN];
|
|
|
|
zilog->zl_replaying_seq--; /* didn't actually replay this one */
|
|
|
|
dmu_objset_name(zilog->zl_os, name);
|
|
|
|
cmn_err(CE_WARN, "ZFS replay transaction error %d, "
|
|
"dataset %s, seq 0x%llx, txtype %llu %s\n", error, name,
|
|
(u_longlong_t)lr->lrc_seq,
|
|
(u_longlong_t)(lr->lrc_txtype & ~TX_CI),
|
|
(lr->lrc_txtype & TX_CI) ? "CI" : "");
|
|
|
|
return (error);
|
|
}
|
|
|
|
static int
|
|
zil_replay_log_record(zilog_t *zilog, const lr_t *lr, void *zra,
|
|
uint64_t claim_txg)
|
|
{
|
|
zil_replay_arg_t *zr = zra;
|
|
const zil_header_t *zh = zilog->zl_header;
|
|
uint64_t reclen = lr->lrc_reclen;
|
|
uint64_t txtype = lr->lrc_txtype;
|
|
int error = 0;
|
|
|
|
zilog->zl_replaying_seq = lr->lrc_seq;
|
|
|
|
if (lr->lrc_seq <= zh->zh_replay_seq) /* already replayed */
|
|
return (0);
|
|
|
|
if (lr->lrc_txg < claim_txg) /* already committed */
|
|
return (0);
|
|
|
|
/* Strip case-insensitive bit, still present in log record */
|
|
txtype &= ~TX_CI;
|
|
|
|
if (txtype == 0 || txtype >= TX_MAX_TYPE)
|
|
return (zil_replay_error(zilog, lr, EINVAL));
|
|
|
|
/*
|
|
* If this record type can be logged out of order, the object
|
|
* (lr_foid) may no longer exist. That's legitimate, not an error.
|
|
*/
|
|
if (TX_OOO(txtype)) {
|
|
error = dmu_object_info(zilog->zl_os,
|
|
LR_FOID_GET_OBJ(((lr_ooo_t *)lr)->lr_foid), NULL);
|
|
if (error == ENOENT || error == EEXIST)
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Make a copy of the data so we can revise and extend it.
|
|
*/
|
|
bcopy(lr, zr->zr_lr, reclen);
|
|
|
|
/*
|
|
* If this is a TX_WRITE with a blkptr, suck in the data.
|
|
*/
|
|
if (txtype == TX_WRITE && reclen == sizeof (lr_write_t)) {
|
|
error = zil_read_log_data(zilog, (lr_write_t *)lr,
|
|
zr->zr_lr + reclen);
|
|
if (error != 0)
|
|
return (zil_replay_error(zilog, lr, error));
|
|
}
|
|
|
|
/*
|
|
* The log block containing this lr may have been byteswapped
|
|
* so that we can easily examine common fields like lrc_txtype.
|
|
* However, the log is a mix of different record types, and only the
|
|
* replay vectors know how to byteswap their records. Therefore, if
|
|
* the lr was byteswapped, undo it before invoking the replay vector.
|
|
*/
|
|
if (zr->zr_byteswap)
|
|
byteswap_uint64_array(zr->zr_lr, reclen);
|
|
|
|
/*
|
|
* We must now do two things atomically: replay this log record,
|
|
* and update the log header sequence number to reflect the fact that
|
|
* we did so. At the end of each replay function the sequence number
|
|
* is updated if we are in replay mode.
|
|
*/
|
|
error = zr->zr_replay[txtype](zr->zr_arg, zr->zr_lr, zr->zr_byteswap);
|
|
if (error != 0) {
|
|
/*
|
|
* The DMU's dnode layer doesn't see removes until the txg
|
|
* commits, so a subsequent claim can spuriously fail with
|
|
* EEXIST. So if we receive any error we try syncing out
|
|
* any removes then retry the transaction. Note that we
|
|
* specify B_FALSE for byteswap now, so we don't do it twice.
|
|
*/
|
|
txg_wait_synced(spa_get_dsl(zilog->zl_spa), 0);
|
|
error = zr->zr_replay[txtype](zr->zr_arg, zr->zr_lr, B_FALSE);
|
|
if (error != 0)
|
|
return (zil_replay_error(zilog, lr, error));
|
|
}
|
|
return (0);
|
|
}
|
|
|
|
/* ARGSUSED */
|
|
static int
|
|
zil_incr_blks(zilog_t *zilog, const blkptr_t *bp, void *arg, uint64_t claim_txg)
|
|
{
|
|
zilog->zl_replay_blks++;
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* If this dataset has a non-empty intent log, replay it and destroy it.
|
|
*/
|
|
void
|
|
zil_replay(objset_t *os, void *arg, zil_replay_func_t *replay_func[TX_MAX_TYPE])
|
|
{
|
|
zilog_t *zilog = dmu_objset_zil(os);
|
|
const zil_header_t *zh = zilog->zl_header;
|
|
zil_replay_arg_t zr;
|
|
|
|
if ((zh->zh_flags & ZIL_REPLAY_NEEDED) == 0) {
|
|
zil_destroy(zilog, B_TRUE);
|
|
return;
|
|
}
|
|
|
|
zr.zr_replay = replay_func;
|
|
zr.zr_arg = arg;
|
|
zr.zr_byteswap = BP_SHOULD_BYTESWAP(&zh->zh_log);
|
|
zr.zr_lr = vmem_alloc(2 * SPA_MAXBLOCKSIZE, KM_SLEEP);
|
|
|
|
/*
|
|
* Wait for in-progress removes to sync before starting replay.
|
|
*/
|
|
txg_wait_synced(zilog->zl_dmu_pool, 0);
|
|
|
|
zilog->zl_replay = B_TRUE;
|
|
zilog->zl_replay_time = ddi_get_lbolt();
|
|
ASSERT(zilog->zl_replay_blks == 0);
|
|
(void) zil_parse(zilog, zil_incr_blks, zil_replay_log_record, &zr,
|
|
zh->zh_claim_txg, B_TRUE);
|
|
vmem_free(zr.zr_lr, 2 * SPA_MAXBLOCKSIZE);
|
|
|
|
zil_destroy(zilog, B_FALSE);
|
|
txg_wait_synced(zilog->zl_dmu_pool, zilog->zl_destroy_txg);
|
|
zilog->zl_replay = B_FALSE;
|
|
}
|
|
|
|
boolean_t
|
|
zil_replaying(zilog_t *zilog, dmu_tx_t *tx)
|
|
{
|
|
if (zilog->zl_sync == ZFS_SYNC_DISABLED)
|
|
return (B_TRUE);
|
|
|
|
if (zilog->zl_replay) {
|
|
dsl_dataset_dirty(dmu_objset_ds(zilog->zl_os), tx);
|
|
zilog->zl_replayed_seq[dmu_tx_get_txg(tx) & TXG_MASK] =
|
|
zilog->zl_replaying_seq;
|
|
return (B_TRUE);
|
|
}
|
|
|
|
return (B_FALSE);
|
|
}
|
|
|
|
/* ARGSUSED */
|
|
int
|
|
zil_reset(const char *osname, void *arg)
|
|
{
|
|
int error;
|
|
|
|
error = zil_suspend(osname, NULL);
|
|
/* EACCES means crypto key not loaded */
|
|
if ((error == EACCES) || (error == EBUSY))
|
|
return (SET_ERROR(error));
|
|
if (error != 0)
|
|
return (SET_ERROR(EEXIST));
|
|
return (0);
|
|
}
|
|
|
|
EXPORT_SYMBOL(zil_alloc);
|
|
EXPORT_SYMBOL(zil_free);
|
|
EXPORT_SYMBOL(zil_open);
|
|
EXPORT_SYMBOL(zil_close);
|
|
EXPORT_SYMBOL(zil_replay);
|
|
EXPORT_SYMBOL(zil_replaying);
|
|
EXPORT_SYMBOL(zil_destroy);
|
|
EXPORT_SYMBOL(zil_destroy_sync);
|
|
EXPORT_SYMBOL(zil_itx_create);
|
|
EXPORT_SYMBOL(zil_itx_destroy);
|
|
EXPORT_SYMBOL(zil_itx_assign);
|
|
EXPORT_SYMBOL(zil_commit);
|
|
EXPORT_SYMBOL(zil_claim);
|
|
EXPORT_SYMBOL(zil_check_log_chain);
|
|
EXPORT_SYMBOL(zil_sync);
|
|
EXPORT_SYMBOL(zil_clean);
|
|
EXPORT_SYMBOL(zil_suspend);
|
|
EXPORT_SYMBOL(zil_resume);
|
|
EXPORT_SYMBOL(zil_lwb_add_block);
|
|
EXPORT_SYMBOL(zil_bp_tree_add);
|
|
EXPORT_SYMBOL(zil_set_sync);
|
|
EXPORT_SYMBOL(zil_set_logbias);
|
|
|
|
/* BEGIN CSTYLED */
|
|
ZFS_MODULE_PARAM(zfs, zfs_, commit_timeout_pct, INT, ZMOD_RW,
|
|
"ZIL block open timeout percentage");
|
|
|
|
ZFS_MODULE_PARAM(zfs_zil, zil_, replay_disable, INT, ZMOD_RW,
|
|
"Disable intent logging replay");
|
|
|
|
ZFS_MODULE_PARAM(zfs_zil, zil_, nocacheflush, INT, ZMOD_RW,
|
|
"Disable ZIL cache flushes");
|
|
|
|
ZFS_MODULE_PARAM(zfs_zil, zil_, slog_bulk, ULONG, ZMOD_RW,
|
|
"Limit in bytes slog sync writes per commit");
|
|
|
|
ZFS_MODULE_PARAM(zfs_zil, zil_, maxblocksize, INT, ZMOD_RW,
|
|
"Limit in bytes of ZIL log block size");
|
|
/* END CSTYLED */
|