Add files missed from r331695.
This commit is contained in:
Alexander Motin
parent
b8a528e092
commit
bce155015b
623
uts/common/fs/zfs/spa_checkpoint.c
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623
uts/common/fs/zfs/spa_checkpoint.c
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/*
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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) 2017 by Delphix. All rights reserved.
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*/
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/*
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* Storage Pool Checkpoint
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*
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* A storage pool checkpoint can be thought of as a pool-wide snapshot or
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* a stable version of extreme rewind that guarantees no blocks from the
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* checkpointed state will have been overwritten. It remembers the entire
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* state of the storage pool (e.g. snapshots, dataset names, etc..) from the
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* point that it was taken and the user can rewind back to that point even if
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* they applied destructive operations on their datasets or even enabled new
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* zpool on-disk features. If a pool has a checkpoint that is no longer
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* needed, the user can discard it.
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*
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* == On disk data structures used ==
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*
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* - The pool has a new feature flag and a new entry in the MOS. The feature
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* flag is set to active when we create the checkpoint and remains active
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* until the checkpoint is fully discarded. The entry in the MOS config
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* (DMU_POOL_ZPOOL_CHECKPOINT) is populated with the uberblock that
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* references the state of the pool when we take the checkpoint. The entry
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* remains populated until we start discarding the checkpoint or we rewind
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* back to it.
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*
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* - Each vdev contains a vdev-wide space map while the pool has a checkpoint,
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* which persists until the checkpoint is fully discarded. The space map
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* contains entries that have been freed in the current state of the pool
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* but we want to keep around in case we decide to rewind to the checkpoint.
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* [see vdev_checkpoint_sm]
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*
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* - Each metaslab's ms_sm space map behaves the same as without the
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* checkpoint, with the only exception being the scenario when we free
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* blocks that belong to the checkpoint. In this case, these blocks remain
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* ALLOCATED in the metaslab's space map and they are added as FREE in the
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* vdev's checkpoint space map.
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*
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* - Each uberblock has a field (ub_checkpoint_txg) which holds the txg that
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* the uberblock was checkpointed. For normal uberblocks this field is 0.
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*
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* == Overview of operations ==
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*
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* - To create a checkpoint, we first wait for the current TXG to be synced,
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* so we can use the most recently synced uberblock (spa_ubsync) as the
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* checkpointed uberblock. Then we use an early synctask to place that
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* uberblock in MOS config, increment the feature flag for the checkpoint
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* (marking it active), and setting spa_checkpoint_txg (see its use below)
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* to the TXG of the checkpointed uberblock. We use an early synctask for
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* the aforementioned operations to ensure that no blocks were dirtied
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* between the current TXG and the TXG of the checkpointed uberblock
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* (e.g the previous txg).
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*
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* - When a checkpoint exists, we need to ensure that the blocks that
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* belong to the checkpoint are freed but never reused. This means that
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* these blocks should never end up in the ms_allocatable or the ms_freeing
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* trees of a metaslab. Therefore, whenever there is a checkpoint the new
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* ms_checkpointing tree is used in addition to the aforementioned ones.
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*
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* Whenever a block is freed and we find out that it is referenced by the
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* checkpoint (we find out by comparing its birth to spa_checkpoint_txg),
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* we place it in the ms_checkpointing tree instead of the ms_freeingtree.
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* This way, we divide the blocks that are being freed into checkpointed
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* and not-checkpointed blocks.
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*
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* In order to persist these frees, we write the extents from the
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* ms_freeingtree to the ms_sm as usual, and the extents from the
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* ms_checkpointing tree to the vdev_checkpoint_sm. This way, these
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* checkpointed extents will remain allocated in the metaslab's ms_sm space
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* map, and therefore won't be reused [see metaslab_sync()]. In addition,
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* when we discard the checkpoint, we can find the entries that have
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* actually been freed in vdev_checkpoint_sm.
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* [see spa_checkpoint_discard_thread_sync()]
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*
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* - To discard the checkpoint we use an early synctask to delete the
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* checkpointed uberblock from the MOS config, set spa_checkpoint_txg to 0,
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* and wakeup the discarding zthr thread (an open-context async thread).
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* We use an early synctask to ensure that the operation happens before any
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* new data end up in the checkpoint's data structures.
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*
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* Once the synctask is done and the discarding zthr is awake, we discard
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* the checkpointed data over multiple TXGs by having the zthr prefetching
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* entries from vdev_checkpoint_sm and then starting a synctask that places
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* them as free blocks in to their respective ms_allocatable and ms_sm
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* structures.
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* [see spa_checkpoint_discard_thread()]
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*
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* When there are no entries left in the vdev_checkpoint_sm of all
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* top-level vdevs, a final synctask runs that decrements the feature flag.
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*
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* - To rewind to the checkpoint, we first use the current uberblock and
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* open the MOS so we can access the checkpointed uberblock from the MOS
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* config. After we retrieve the checkpointed uberblock, we use it as the
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* current uberblock for the pool by writing it to disk with an updated
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* TXG, opening its version of the MOS, and moving on as usual from there.
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* [see spa_ld_checkpoint_rewind()]
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*
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* An important note on rewinding to the checkpoint has to do with how we
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* handle ZIL blocks. In the scenario of a rewind, we clear out any ZIL
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* blocks that have not been claimed by the time we took the checkpoint
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* as they should no longer be valid.
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* [see comment in zil_claim()]
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*
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* == Miscellaneous information ==
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*
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* - In the hypothetical event that we take a checkpoint, remove a vdev,
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* and attempt to rewind, the rewind would fail as the checkpointed
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* uberblock would reference data in the removed device. For this reason
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* and others of similar nature, we disallow the following operations that
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* can change the config:
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* vdev removal and attach/detach, mirror splitting, and pool reguid.
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*
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* - As most of the checkpoint logic is implemented in the SPA and doesn't
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* distinguish datasets when it comes to space accounting, having a
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* checkpoint can potentially break the boundaries set by dataset
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* reservations.
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*/
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#include <sys/dmu_tx.h>
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#include <sys/dsl_dir.h>
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#include <sys/dsl_synctask.h>
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#include <sys/metaslab_impl.h>
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#include <sys/spa.h>
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#include <sys/spa_impl.h>
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#include <sys/spa_checkpoint.h>
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#include <sys/vdev_impl.h>
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#include <sys/zap.h>
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#include <sys/zfeature.h>
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/*
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* The following parameter limits the amount of memory to be used for the
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* prefetching of the checkpoint space map done on each vdev while
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* discarding the checkpoint.
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*
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* The reason it exists is because top-level vdevs with long checkpoint
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* space maps can potentially take up a lot of memory depending on the
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* amount of checkpointed data that has been freed within them while
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* the pool had a checkpoint.
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*/
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uint64_t zfs_spa_discard_memory_limit = 16 * 1024 * 1024;
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int
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spa_checkpoint_get_stats(spa_t *spa, pool_checkpoint_stat_t *pcs)
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{
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if (!spa_feature_is_active(spa, SPA_FEATURE_POOL_CHECKPOINT))
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return (SET_ERROR(ZFS_ERR_NO_CHECKPOINT));
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bzero(pcs, sizeof (pool_checkpoint_stat_t));
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int error = zap_contains(spa_meta_objset(spa),
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DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_ZPOOL_CHECKPOINT);
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ASSERT(error == 0 || error == ENOENT);
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if (error == ENOENT)
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pcs->pcs_state = CS_CHECKPOINT_DISCARDING;
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else
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pcs->pcs_state = CS_CHECKPOINT_EXISTS;
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pcs->pcs_space = spa->spa_checkpoint_info.sci_dspace;
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pcs->pcs_start_time = spa->spa_checkpoint_info.sci_timestamp;
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return (0);
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}
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static void
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spa_checkpoint_discard_complete_sync(void *arg, dmu_tx_t *tx)
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{
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spa_t *spa = arg;
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spa->spa_checkpoint_info.sci_timestamp = 0;
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spa_feature_decr(spa, SPA_FEATURE_POOL_CHECKPOINT, tx);
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spa_history_log_internal(spa, "spa discard checkpoint", tx,
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"finished discarding checkpointed state from the pool");
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}
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typedef struct spa_checkpoint_discard_sync_callback_arg {
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vdev_t *sdc_vd;
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uint64_t sdc_txg;
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uint64_t sdc_entry_limit;
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} spa_checkpoint_discard_sync_callback_arg_t;
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static int
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spa_checkpoint_discard_sync_callback(maptype_t type, uint64_t offset,
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uint64_t size, void *arg)
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{
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spa_checkpoint_discard_sync_callback_arg_t *sdc = arg;
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vdev_t *vd = sdc->sdc_vd;
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metaslab_t *ms = vd->vdev_ms[offset >> vd->vdev_ms_shift];
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uint64_t end = offset + size;
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if (sdc->sdc_entry_limit == 0)
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return (EINTR);
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/*
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* Since the space map is not condensed, we know that
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* none of its entries is crossing the boundaries of
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* its respective metaslab.
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*
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* That said, there is no fundamental requirement that
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* the checkpoint's space map entries should not cross
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* metaslab boundaries. So if needed we could add code
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* that handles metaslab-crossing segments in the future.
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*/
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VERIFY3U(type, ==, SM_FREE);
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VERIFY3U(offset, >=, ms->ms_start);
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VERIFY3U(end, <=, ms->ms_start + ms->ms_size);
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/*
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* At this point we should not be processing any
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* other frees concurrently, so the lock is technically
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* unnecessary. We use the lock anyway though to
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* potentially save ourselves from future headaches.
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*/
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mutex_enter(&ms->ms_lock);
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if (range_tree_is_empty(ms->ms_freeing))
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vdev_dirty(vd, VDD_METASLAB, ms, sdc->sdc_txg);
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range_tree_add(ms->ms_freeing, offset, size);
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mutex_exit(&ms->ms_lock);
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ASSERT3U(vd->vdev_spa->spa_checkpoint_info.sci_dspace, >=, size);
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ASSERT3U(vd->vdev_stat.vs_checkpoint_space, >=, size);
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vd->vdev_spa->spa_checkpoint_info.sci_dspace -= size;
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vd->vdev_stat.vs_checkpoint_space -= size;
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sdc->sdc_entry_limit--;
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return (0);
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}
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static void
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spa_checkpoint_accounting_verify(spa_t *spa)
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{
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vdev_t *rvd = spa->spa_root_vdev;
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uint64_t ckpoint_sm_space_sum = 0;
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uint64_t vs_ckpoint_space_sum = 0;
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for (uint64_t c = 0; c < rvd->vdev_children; c++) {
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vdev_t *vd = rvd->vdev_child[c];
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if (vd->vdev_checkpoint_sm != NULL) {
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ckpoint_sm_space_sum +=
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-vd->vdev_checkpoint_sm->sm_alloc;
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vs_ckpoint_space_sum +=
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vd->vdev_stat.vs_checkpoint_space;
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ASSERT3U(ckpoint_sm_space_sum, ==,
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vs_ckpoint_space_sum);
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} else {
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ASSERT0(vd->vdev_stat.vs_checkpoint_space);
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}
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}
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ASSERT3U(spa->spa_checkpoint_info.sci_dspace, ==, ckpoint_sm_space_sum);
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}
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static void
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spa_checkpoint_discard_thread_sync(void *arg, dmu_tx_t *tx)
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{
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vdev_t *vd = arg;
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int error;
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/*
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* The space map callback is applied only to non-debug entries.
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* Because the number of debug entries is less or equal to the
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* number of non-debug entries, we want to ensure that we only
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* read what we prefetched from open-context.
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*
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* Thus, we set the maximum entries that the space map callback
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* will be applied to be half the entries that could fit in the
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* imposed memory limit.
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*/
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uint64_t max_entry_limit =
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(zfs_spa_discard_memory_limit / sizeof (uint64_t)) >> 1;
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uint64_t entries_in_sm =
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space_map_length(vd->vdev_checkpoint_sm) / sizeof (uint64_t);
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/*
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* Iterate from the end of the space map towards the beginning,
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* placing its entries on ms_freeing and removing them from the
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* space map. The iteration stops if one of the following
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* conditions is true:
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*
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* 1] We reached the beginning of the space map. At this point
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* the space map should be completely empty and
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* space_map_incremental_destroy should have returned 0.
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* The next step would be to free and close the space map
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* and remove its entry from its vdev's top zap. This allows
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* spa_checkpoint_discard_thread() to move on to the next vdev.
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*
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* 2] We reached the memory limit (amount of memory used to hold
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* space map entries in memory) and space_map_incremental_destroy
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* returned EINTR. This means that there are entries remaining
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* in the space map that will be cleared in a future invocation
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* of this function by spa_checkpoint_discard_thread().
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*/
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spa_checkpoint_discard_sync_callback_arg_t sdc;
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sdc.sdc_vd = vd;
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sdc.sdc_txg = tx->tx_txg;
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sdc.sdc_entry_limit = MIN(entries_in_sm, max_entry_limit);
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uint64_t entries_before = entries_in_sm;
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error = space_map_incremental_destroy(vd->vdev_checkpoint_sm,
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spa_checkpoint_discard_sync_callback, &sdc, tx);
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uint64_t entries_after =
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space_map_length(vd->vdev_checkpoint_sm) / sizeof (uint64_t);
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#ifdef DEBUG
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spa_checkpoint_accounting_verify(vd->vdev_spa);
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#endif
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zfs_dbgmsg("discarding checkpoint: txg %llu, vdev id %d, "
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"deleted %llu entries - %llu entries are left",
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tx->tx_txg, vd->vdev_id, (entries_before - entries_after),
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entries_after);
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if (error != EINTR) {
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if (error != 0) {
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zfs_panic_recover("zfs: error %d was returned "
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"while incrementally destroying the checkpoint "
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"space map of vdev %llu\n",
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error, vd->vdev_id);
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}
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ASSERT0(entries_after);
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ASSERT0(vd->vdev_checkpoint_sm->sm_alloc);
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ASSERT0(vd->vdev_checkpoint_sm->sm_length);
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space_map_free(vd->vdev_checkpoint_sm, tx);
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space_map_close(vd->vdev_checkpoint_sm);
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vd->vdev_checkpoint_sm = NULL;
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VERIFY0(zap_remove(vd->vdev_spa->spa_meta_objset,
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vd->vdev_top_zap, VDEV_TOP_ZAP_POOL_CHECKPOINT_SM, tx));
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}
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}
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static boolean_t
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spa_checkpoint_discard_is_done(spa_t *spa)
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{
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vdev_t *rvd = spa->spa_root_vdev;
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ASSERT(!spa_has_checkpoint(spa));
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ASSERT(spa_feature_is_active(spa, SPA_FEATURE_POOL_CHECKPOINT));
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for (uint64_t c = 0; c < rvd->vdev_children; c++) {
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if (rvd->vdev_child[c]->vdev_checkpoint_sm != NULL)
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return (B_FALSE);
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ASSERT0(rvd->vdev_child[c]->vdev_stat.vs_checkpoint_space);
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}
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return (B_TRUE);
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}
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/* ARGSUSED */
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boolean_t
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spa_checkpoint_discard_thread_check(void *arg, zthr_t *zthr)
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{
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spa_t *spa = arg;
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if (!spa_feature_is_active(spa, SPA_FEATURE_POOL_CHECKPOINT))
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return (B_FALSE);
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if (spa_has_checkpoint(spa))
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return (B_FALSE);
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return (B_TRUE);
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}
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int
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spa_checkpoint_discard_thread(void *arg, zthr_t *zthr)
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{
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spa_t *spa = arg;
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vdev_t *rvd = spa->spa_root_vdev;
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for (uint64_t c = 0; c < rvd->vdev_children; c++) {
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vdev_t *vd = rvd->vdev_child[c];
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while (vd->vdev_checkpoint_sm != NULL) {
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space_map_t *checkpoint_sm = vd->vdev_checkpoint_sm;
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int numbufs;
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dmu_buf_t **dbp;
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if (zthr_iscancelled(zthr))
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return (0);
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ASSERT3P(vd->vdev_ops, !=, &vdev_indirect_ops);
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uint64_t size = MIN(space_map_length(checkpoint_sm),
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zfs_spa_discard_memory_limit);
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uint64_t offset =
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space_map_length(checkpoint_sm) - size;
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/*
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* Ensure that the part of the space map that will
|
||||
* be destroyed by the synctask, is prefetched in
|
||||
* memory before the synctask runs.
|
||||
*/
|
||||
int error = dmu_buf_hold_array_by_bonus(
|
||||
checkpoint_sm->sm_dbuf, offset, size,
|
||||
B_TRUE, FTAG, &numbufs, &dbp);
|
||||
if (error != 0) {
|
||||
zfs_panic_recover("zfs: error %d was returned "
|
||||
"while prefetching checkpoint space map "
|
||||
"entries of vdev %llu\n",
|
||||
error, vd->vdev_id);
|
||||
}
|
||||
|
||||
VERIFY0(dsl_sync_task(spa->spa_name, NULL,
|
||||
spa_checkpoint_discard_thread_sync, vd,
|
||||
0, ZFS_SPACE_CHECK_NONE));
|
||||
|
||||
dmu_buf_rele_array(dbp, numbufs, FTAG);
|
||||
}
|
||||
}
|
||||
|
||||
VERIFY(spa_checkpoint_discard_is_done(spa));
|
||||
VERIFY0(spa->spa_checkpoint_info.sci_dspace);
|
||||
VERIFY0(dsl_sync_task(spa->spa_name, NULL,
|
||||
spa_checkpoint_discard_complete_sync, spa,
|
||||
0, ZFS_SPACE_CHECK_NONE));
|
||||
|
||||
return (0);
|
||||
}
|
||||
|
||||
|
||||
/* ARGSUSED */
|
||||
static int
|
||||
spa_checkpoint_check(void *arg, dmu_tx_t *tx)
|
||||
{
|
||||
spa_t *spa = dmu_tx_pool(tx)->dp_spa;
|
||||
|
||||
if (!spa_feature_is_enabled(spa, SPA_FEATURE_POOL_CHECKPOINT))
|
||||
return (SET_ERROR(ENOTSUP));
|
||||
|
||||
if (!spa_top_vdevs_spacemap_addressable(spa))
|
||||
return (SET_ERROR(ZFS_ERR_VDEV_TOO_BIG));
|
||||
|
||||
if (spa->spa_vdev_removal != NULL)
|
||||
return (SET_ERROR(ZFS_ERR_DEVRM_IN_PROGRESS));
|
||||
|
||||
if (spa->spa_checkpoint_txg != 0)
|
||||
return (SET_ERROR(ZFS_ERR_CHECKPOINT_EXISTS));
|
||||
|
||||
if (spa_feature_is_active(spa, SPA_FEATURE_POOL_CHECKPOINT))
|
||||
return (SET_ERROR(ZFS_ERR_DISCARDING_CHECKPOINT));
|
||||
|
||||
return (0);
|
||||
}
|
||||
|
||||
/* ARGSUSED */
|
||||
static void
|
||||
spa_checkpoint_sync(void *arg, dmu_tx_t *tx)
|
||||
{
|
||||
dsl_pool_t *dp = dmu_tx_pool(tx);
|
||||
spa_t *spa = dp->dp_spa;
|
||||
uberblock_t checkpoint = spa->spa_ubsync;
|
||||
|
||||
/*
|
||||
* At this point, there should not be a checkpoint in the MOS.
|
||||
*/
|
||||
ASSERT3U(zap_contains(spa_meta_objset(spa), DMU_POOL_DIRECTORY_OBJECT,
|
||||
DMU_POOL_ZPOOL_CHECKPOINT), ==, ENOENT);
|
||||
|
||||
ASSERT0(spa->spa_checkpoint_info.sci_timestamp);
|
||||
ASSERT0(spa->spa_checkpoint_info.sci_dspace);
|
||||
|
||||
/*
|
||||
* Since the checkpointed uberblock is the one that just got synced
|
||||
* (we use spa_ubsync), its txg must be equal to the txg number of
|
||||
* the txg we are syncing, minus 1.
|
||||
*/
|
||||
ASSERT3U(checkpoint.ub_txg, ==, spa->spa_syncing_txg - 1);
|
||||
|
||||
/*
|
||||
* Once the checkpoint is in place, we need to ensure that none of
|
||||
* its blocks will be marked for reuse after it has been freed.
|
||||
* When there is a checkpoint and a block is freed, we compare its
|
||||
* birth txg to the txg of the checkpointed uberblock to see if the
|
||||
* block is part of the checkpoint or not. Therefore, we have to set
|
||||
* spa_checkpoint_txg before any frees happen in this txg (which is
|
||||
* why this is done as an early_synctask as explained in the comment
|
||||
* in spa_checkpoint()).
|
||||
*/
|
||||
spa->spa_checkpoint_txg = checkpoint.ub_txg;
|
||||
spa->spa_checkpoint_info.sci_timestamp = checkpoint.ub_timestamp;
|
||||
|
||||
checkpoint.ub_checkpoint_txg = checkpoint.ub_txg;
|
||||
VERIFY0(zap_add(spa->spa_dsl_pool->dp_meta_objset,
|
||||
DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_ZPOOL_CHECKPOINT,
|
||||
sizeof (uint64_t), sizeof (uberblock_t) / sizeof (uint64_t),
|
||||
&checkpoint, tx));
|
||||
|
||||
/*
|
||||
* Increment the feature refcount and thus activate the feature.
|
||||
* Note that the feature will be deactivated when we've
|
||||
* completely discarded all checkpointed state (both vdev
|
||||
* space maps and uberblock).
|
||||
*/
|
||||
spa_feature_incr(spa, SPA_FEATURE_POOL_CHECKPOINT, tx);
|
||||
|
||||
spa_history_log_internal(spa, "spa checkpoint", tx,
|
||||
"checkpointed uberblock txg=%llu", checkpoint.ub_txg);
|
||||
}
|
||||
|
||||
/*
|
||||
* Create a checkpoint for the pool.
|
||||
*/
|
||||
int
|
||||
spa_checkpoint(const char *pool)
|
||||
{
|
||||
int error;
|
||||
spa_t *spa;
|
||||
|
||||
error = spa_open(pool, &spa, FTAG);
|
||||
if (error != 0)
|
||||
return (error);
|
||||
|
||||
mutex_enter(&spa->spa_vdev_top_lock);
|
||||
|
||||
/*
|
||||
* Wait for current syncing txg to finish so the latest synced
|
||||
* uberblock (spa_ubsync) has all the changes that we expect
|
||||
* to see if we were to revert later to the checkpoint. In other
|
||||
* words we want the checkpointed uberblock to include/reference
|
||||
* all the changes that were pending at the time that we issued
|
||||
* the checkpoint command.
|
||||
*/
|
||||
txg_wait_synced(spa_get_dsl(spa), 0);
|
||||
|
||||
/*
|
||||
* As the checkpointed uberblock references blocks from the previous
|
||||
* txg (spa_ubsync) we want to ensure that are not freeing any of
|
||||
* these blocks in the same txg that the following synctask will
|
||||
* run. Thus, we run it as an early synctask, so the dirty changes
|
||||
* that are synced to disk afterwards during zios and other synctasks
|
||||
* do not reuse checkpointed blocks.
|
||||
*/
|
||||
error = dsl_early_sync_task(pool, spa_checkpoint_check,
|
||||
spa_checkpoint_sync, NULL, 0, ZFS_SPACE_CHECK_NORMAL);
|
||||
|
||||
mutex_exit(&spa->spa_vdev_top_lock);
|
||||
|
||||
spa_close(spa, FTAG);
|
||||
return (error);
|
||||
}
|
||||
|
||||
/* ARGSUSED */
|
||||
static int
|
||||
spa_checkpoint_discard_check(void *arg, dmu_tx_t *tx)
|
||||
{
|
||||
spa_t *spa = dmu_tx_pool(tx)->dp_spa;
|
||||
|
||||
if (!spa_feature_is_active(spa, SPA_FEATURE_POOL_CHECKPOINT))
|
||||
return (SET_ERROR(ZFS_ERR_NO_CHECKPOINT));
|
||||
|
||||
if (spa->spa_checkpoint_txg == 0)
|
||||
return (SET_ERROR(ZFS_ERR_DISCARDING_CHECKPOINT));
|
||||
|
||||
VERIFY0(zap_contains(spa_meta_objset(spa),
|
||||
DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_ZPOOL_CHECKPOINT));
|
||||
|
||||
return (0);
|
||||
}
|
||||
|
||||
/* ARGSUSED */
|
||||
static void
|
||||
spa_checkpoint_discard_sync(void *arg, dmu_tx_t *tx)
|
||||
{
|
||||
spa_t *spa = dmu_tx_pool(tx)->dp_spa;
|
||||
|
||||
VERIFY0(zap_remove(spa_meta_objset(spa), DMU_POOL_DIRECTORY_OBJECT,
|
||||
DMU_POOL_ZPOOL_CHECKPOINT, tx));
|
||||
|
||||
spa->spa_checkpoint_txg = 0;
|
||||
|
||||
zthr_wakeup(spa->spa_checkpoint_discard_zthr);
|
||||
|
||||
spa_history_log_internal(spa, "spa discard checkpoint", tx,
|
||||
"started discarding checkpointed state from the pool");
|
||||
}
|
||||
|
||||
/*
|
||||
* Discard the checkpoint from a pool.
|
||||
*/
|
||||
int
|
||||
spa_checkpoint_discard(const char *pool)
|
||||
{
|
||||
/*
|
||||
* Similarly to spa_checkpoint(), we want our synctask to run
|
||||
* before any pending dirty data are written to disk so they
|
||||
* won't end up in the checkpoint's data structures (e.g.
|
||||
* ms_checkpointing and vdev_checkpoint_sm) and re-create any
|
||||
* space maps that the discarding open-context thread has
|
||||
* deleted.
|
||||
* [see spa_discard_checkpoint_sync and spa_discard_checkpoint_thread]
|
||||
*/
|
||||
return (dsl_early_sync_task(pool, spa_checkpoint_discard_check,
|
||||
spa_checkpoint_discard_sync, NULL, 0,
|
||||
ZFS_SPACE_CHECK_DISCARD_CHECKPOINT));
|
||||
}
|
||||
44
uts/common/fs/zfs/sys/spa_checkpoint.h
Normal file
44
uts/common/fs/zfs/sys/spa_checkpoint.h
Normal file
@ -0,0 +1,44 @@
|
||||
/*
|
||||
* CDDL HEADER START
|
||||
*
|
||||
* The contents of this file are subject to the terms of the
|
||||
* Common Development and Distribution License (the "License").
|
||||
* You may not use this file except in compliance with the License.
|
||||
*
|
||||
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
|
||||
* or http://www.opensolaris.org/os/licensing.
|
||||
* See the License for the specific language governing permissions
|
||||
* and limitations under the License.
|
||||
*
|
||||
* When distributing Covered Code, include this CDDL HEADER in each
|
||||
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
|
||||
* If applicable, add the following below this CDDL HEADER, with the
|
||||
* fields enclosed by brackets "[]" replaced with your own identifying
|
||||
* information: Portions Copyright [yyyy] [name of copyright owner]
|
||||
*
|
||||
* CDDL HEADER END
|
||||
*/
|
||||
|
||||
/*
|
||||
* Copyright (c) 2017 by Delphix. All rights reserved.
|
||||
*/
|
||||
|
||||
#ifndef _SYS_SPA_CHECKPOINT_H
|
||||
#define _SYS_SPA_CHECKPOINT_H
|
||||
|
||||
#include <sys/zthr.h>
|
||||
|
||||
typedef struct spa_checkpoint_info {
|
||||
uint64_t sci_timestamp; /* when checkpointed uberblock was synced */
|
||||
uint64_t sci_dspace; /* disk space used by checkpoint in bytes */
|
||||
} spa_checkpoint_info_t;
|
||||
|
||||
int spa_checkpoint(const char *);
|
||||
int spa_checkpoint_discard(const char *);
|
||||
|
||||
boolean_t spa_checkpoint_discard_thread_check(void *, zthr_t *);
|
||||
int spa_checkpoint_discard_thread(void *, zthr_t *);
|
||||
|
||||
int spa_checkpoint_get_stats(spa_t *, pool_checkpoint_stat_t *);
|
||||
|
||||
#endif /* _SYS_SPA_CHECKPOINT_H */
|
||||
Loading…
Reference in New Issue
Block a user