Index: stable/12/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_pool.c =================================================================== --- stable/12/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_pool.c (revision 348909) +++ stable/12/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_pool.c (revision 348910) @@ -1,1366 +1,1370 @@ /* * 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) 2005, 2010, Oracle and/or its affiliates. All rights reserved. * Copyright (c) 2011, 2017 by Delphix. All rights reserved. * Copyright (c) 2013 Steven Hartland. All rights reserved. * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved. * Copyright (c) 2014 Integros [integros.com] * Copyright 2016 Nexenta Systems, Inc. All rights reserved. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if defined(__FreeBSD__) && defined(_KERNEL) #include #include #endif /* * ZFS Write Throttle * ------------------ * * ZFS must limit the rate of incoming writes to the rate at which it is able * to sync data modifications to the backend storage. Throttling by too much * creates an artificial limit; throttling by too little can only be sustained * for short periods and would lead to highly lumpy performance. On a per-pool * basis, ZFS tracks the amount of modified (dirty) data. As operations change * data, the amount of dirty data increases; as ZFS syncs out data, the amount * of dirty data decreases. When the amount of dirty data exceeds a * predetermined threshold further modifications are blocked until the amount * of dirty data decreases (as data is synced out). * * The limit on dirty data is tunable, and should be adjusted according to * both the IO capacity and available memory of the system. The larger the * window, the more ZFS is able to aggregate and amortize metadata (and data) * changes. However, memory is a limited resource, and allowing for more dirty * data comes at the cost of keeping other useful data in memory (for example * ZFS data cached by the ARC). * * Implementation * * As buffers are modified dsl_pool_willuse_space() increments both the per- * txg (dp_dirty_pertxg[]) and poolwide (dp_dirty_total) accounting of * dirty space used; dsl_pool_dirty_space() decrements those values as data * is synced out from dsl_pool_sync(). While only the poolwide value is * relevant, the per-txg value is useful for debugging. The tunable * zfs_dirty_data_max determines the dirty space limit. Once that value is * exceeded, new writes are halted until space frees up. * * The zfs_dirty_data_sync tunable dictates the threshold at which we * ensure that there is a txg syncing (see the comment in txg.c for a full * description of transaction group stages). * * The IO scheduler uses both the dirty space limit and current amount of * dirty data as inputs. Those values affect the number of concurrent IOs ZFS * issues. See the comment in vdev_queue.c for details of the IO scheduler. * * The delay is also calculated based on the amount of dirty data. See the * comment above dmu_tx_delay() for details. */ /* * zfs_dirty_data_max will be set to zfs_dirty_data_max_percent% of all memory, * capped at zfs_dirty_data_max_max. It can also be overridden in /etc/system. */ uint64_t zfs_dirty_data_max; uint64_t zfs_dirty_data_max_max = 4ULL * 1024 * 1024 * 1024; int zfs_dirty_data_max_percent = 10; /* - * If there is at least this much dirty data, push out a txg. + * If there's at least this much dirty data (as a percentage of + * zfs_dirty_data_max), push out a txg. This should be less than + * zfs_vdev_async_write_active_min_dirty_percent. */ -uint64_t zfs_dirty_data_sync = 64 * 1024 * 1024; +uint64_t zfs_dirty_data_sync_pct = 20; /* * Once there is this amount of dirty data, the dmu_tx_delay() will kick in * and delay each transaction. * This value should be >= zfs_vdev_async_write_active_max_dirty_percent. */ int zfs_delay_min_dirty_percent = 60; /* * This controls how quickly the delay approaches infinity. * Larger values cause it to delay more for a given amount of dirty data. * Therefore larger values will cause there to be less dirty data for a * given throughput. * * For the smoothest delay, this value should be about 1 billion divided * by the maximum number of operations per second. This will smoothly * handle between 10x and 1/10th this number. * * Note: zfs_delay_scale * zfs_dirty_data_max must be < 2^64, due to the * multiply in dmu_tx_delay(). */ uint64_t zfs_delay_scale = 1000 * 1000 * 1000 / 2000; /* * This determines the number of threads used by the dp_sync_taskq. */ int zfs_sync_taskq_batch_pct = 75; /* * These tunables determine the behavior of how zil_itxg_clean() is * called via zil_clean() in the context of spa_sync(). When an itxg * list needs to be cleaned, TQ_NOSLEEP will be used when dispatching. * If the dispatch fails, the call to zil_itxg_clean() will occur * synchronously in the context of spa_sync(), which can negatively * impact the performance of spa_sync() (e.g. in the case of the itxg * list having a large number of itxs that needs to be cleaned). * * Thus, these tunables can be used to manipulate the behavior of the * taskq used by zil_clean(); they determine the number of taskq entries * that are pre-populated when the taskq is first created (via the * "zfs_zil_clean_taskq_minalloc" tunable) and the maximum number of * taskq entries that are cached after an on-demand allocation (via the * "zfs_zil_clean_taskq_maxalloc"). * * The idea being, we want to try reasonably hard to ensure there will * already be a taskq entry pre-allocated by the time that it is needed * by zil_clean(). This way, we can avoid the possibility of an * on-demand allocation of a new taskq entry from failing, which would * result in zil_itxg_clean() being called synchronously from zil_clean() * (which can adversely affect performance of spa_sync()). * * Additionally, the number of threads used by the taskq can be * configured via the "zfs_zil_clean_taskq_nthr_pct" tunable. */ int zfs_zil_clean_taskq_nthr_pct = 100; int zfs_zil_clean_taskq_minalloc = 1024; int zfs_zil_clean_taskq_maxalloc = 1024 * 1024; #if defined(__FreeBSD__) && defined(_KERNEL) extern int zfs_vdev_async_write_active_max_dirty_percent; SYSCTL_DECL(_vfs_zfs); SYSCTL_UQUAD(_vfs_zfs, OID_AUTO, dirty_data_max, CTLFLAG_RWTUN, &zfs_dirty_data_max, 0, "The maximum amount of dirty data in bytes after which new writes are " "halted until space becomes available"); SYSCTL_UQUAD(_vfs_zfs, OID_AUTO, dirty_data_max_max, CTLFLAG_RDTUN, &zfs_dirty_data_max_max, 0, "The absolute cap on dirty_data_max when auto calculating"); static int sysctl_zfs_dirty_data_max_percent(SYSCTL_HANDLER_ARGS); SYSCTL_PROC(_vfs_zfs, OID_AUTO, dirty_data_max_percent, CTLTYPE_INT | CTLFLAG_MPSAFE | CTLFLAG_RWTUN, 0, sizeof(int), sysctl_zfs_dirty_data_max_percent, "I", "The percent of physical memory used to auto calculate dirty_data_max"); -SYSCTL_UQUAD(_vfs_zfs, OID_AUTO, dirty_data_sync, CTLFLAG_RWTUN, - &zfs_dirty_data_sync, 0, - "Force a txg if the number of dirty buffer bytes exceed this value"); +SYSCTL_UQUAD(_vfs_zfs, OID_AUTO, dirty_data_sync_pct, CTLFLAG_RWTUN, + &zfs_dirty_data_sync_pct, 0, + "Force a txg if the percent of dirty buffer bytes exceed this value"); static int sysctl_zfs_delay_min_dirty_percent(SYSCTL_HANDLER_ARGS); /* No zfs_delay_min_dirty_percent tunable due to limit requirements */ SYSCTL_PROC(_vfs_zfs, OID_AUTO, delay_min_dirty_percent, CTLTYPE_INT | CTLFLAG_MPSAFE | CTLFLAG_RW, 0, sizeof(int), sysctl_zfs_delay_min_dirty_percent, "I", "The limit of outstanding dirty data before transactions are delayed"); static int sysctl_zfs_delay_scale(SYSCTL_HANDLER_ARGS); /* No zfs_delay_scale tunable due to limit requirements */ SYSCTL_PROC(_vfs_zfs, OID_AUTO, delay_scale, CTLTYPE_U64 | CTLFLAG_MPSAFE | CTLFLAG_RW, 0, sizeof(uint64_t), sysctl_zfs_delay_scale, "QU", "Controls how quickly the delay approaches infinity"); static int sysctl_zfs_dirty_data_max_percent(SYSCTL_HANDLER_ARGS) { int val, err; val = zfs_dirty_data_max_percent; err = sysctl_handle_int(oidp, &val, 0, req); if (err != 0 || req->newptr == NULL) return (err); if (val < 0 || val > 100) return (EINVAL); zfs_dirty_data_max_percent = val; return (0); } static int sysctl_zfs_delay_min_dirty_percent(SYSCTL_HANDLER_ARGS) { int val, err; val = zfs_delay_min_dirty_percent; err = sysctl_handle_int(oidp, &val, 0, req); if (err != 0 || req->newptr == NULL) return (err); if (val < zfs_vdev_async_write_active_max_dirty_percent) return (EINVAL); zfs_delay_min_dirty_percent = val; return (0); } static int sysctl_zfs_delay_scale(SYSCTL_HANDLER_ARGS) { uint64_t val; int err; val = zfs_delay_scale; err = sysctl_handle_64(oidp, &val, 0, req); if (err != 0 || req->newptr == NULL) return (err); if (val > UINT64_MAX / zfs_dirty_data_max) return (EINVAL); zfs_delay_scale = val; return (0); } #endif int dsl_pool_open_special_dir(dsl_pool_t *dp, const char *name, dsl_dir_t **ddp) { uint64_t obj; int err; err = zap_lookup(dp->dp_meta_objset, dsl_dir_phys(dp->dp_root_dir)->dd_child_dir_zapobj, name, sizeof (obj), 1, &obj); if (err) return (err); return (dsl_dir_hold_obj(dp, obj, name, dp, ddp)); } static dsl_pool_t * dsl_pool_open_impl(spa_t *spa, uint64_t txg) { dsl_pool_t *dp; blkptr_t *bp = spa_get_rootblkptr(spa); dp = kmem_zalloc(sizeof (dsl_pool_t), KM_SLEEP); dp->dp_spa = spa; dp->dp_meta_rootbp = *bp; rrw_init(&dp->dp_config_rwlock, B_TRUE); txg_init(dp, txg); txg_list_create(&dp->dp_dirty_datasets, spa, offsetof(dsl_dataset_t, ds_dirty_link)); txg_list_create(&dp->dp_dirty_zilogs, spa, offsetof(zilog_t, zl_dirty_link)); txg_list_create(&dp->dp_dirty_dirs, spa, offsetof(dsl_dir_t, dd_dirty_link)); txg_list_create(&dp->dp_sync_tasks, spa, offsetof(dsl_sync_task_t, dst_node)); txg_list_create(&dp->dp_early_sync_tasks, spa, offsetof(dsl_sync_task_t, dst_node)); dp->dp_sync_taskq = taskq_create("dp_sync_taskq", zfs_sync_taskq_batch_pct, minclsyspri, 1, INT_MAX, TASKQ_THREADS_CPU_PCT); dp->dp_zil_clean_taskq = taskq_create("dp_zil_clean_taskq", zfs_zil_clean_taskq_nthr_pct, minclsyspri, zfs_zil_clean_taskq_minalloc, zfs_zil_clean_taskq_maxalloc, TASKQ_PREPOPULATE | TASKQ_THREADS_CPU_PCT); mutex_init(&dp->dp_lock, NULL, MUTEX_DEFAULT, NULL); cv_init(&dp->dp_spaceavail_cv, NULL, CV_DEFAULT, NULL); dp->dp_vnrele_taskq = taskq_create("zfs_vn_rele_taskq", 1, minclsyspri, 1, 4, 0); return (dp); } int dsl_pool_init(spa_t *spa, uint64_t txg, dsl_pool_t **dpp) { int err; dsl_pool_t *dp = dsl_pool_open_impl(spa, txg); err = dmu_objset_open_impl(spa, NULL, &dp->dp_meta_rootbp, &dp->dp_meta_objset); if (err != 0) dsl_pool_close(dp); else *dpp = dp; return (err); } int dsl_pool_open(dsl_pool_t *dp) { int err; dsl_dir_t *dd; dsl_dataset_t *ds; uint64_t obj; rrw_enter(&dp->dp_config_rwlock, RW_WRITER, FTAG); err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_ROOT_DATASET, sizeof (uint64_t), 1, &dp->dp_root_dir_obj); if (err) goto out; err = dsl_dir_hold_obj(dp, dp->dp_root_dir_obj, NULL, dp, &dp->dp_root_dir); if (err) goto out; err = dsl_pool_open_special_dir(dp, MOS_DIR_NAME, &dp->dp_mos_dir); if (err) goto out; if (spa_version(dp->dp_spa) >= SPA_VERSION_ORIGIN) { err = dsl_pool_open_special_dir(dp, ORIGIN_DIR_NAME, &dd); if (err) goto out; err = dsl_dataset_hold_obj(dp, dsl_dir_phys(dd)->dd_head_dataset_obj, FTAG, &ds); if (err == 0) { err = dsl_dataset_hold_obj(dp, dsl_dataset_phys(ds)->ds_prev_snap_obj, dp, &dp->dp_origin_snap); dsl_dataset_rele(ds, FTAG); } dsl_dir_rele(dd, dp); if (err) goto out; } if (spa_version(dp->dp_spa) >= SPA_VERSION_DEADLISTS) { err = dsl_pool_open_special_dir(dp, FREE_DIR_NAME, &dp->dp_free_dir); if (err) goto out; err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_FREE_BPOBJ, sizeof (uint64_t), 1, &obj); if (err) goto out; VERIFY0(bpobj_open(&dp->dp_free_bpobj, dp->dp_meta_objset, obj)); } if (spa_feature_is_active(dp->dp_spa, SPA_FEATURE_OBSOLETE_COUNTS)) { err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_OBSOLETE_BPOBJ, sizeof (uint64_t), 1, &obj); if (err == 0) { VERIFY0(bpobj_open(&dp->dp_obsolete_bpobj, dp->dp_meta_objset, obj)); } else if (err == ENOENT) { /* * We might not have created the remap bpobj yet. */ err = 0; } else { goto out; } } /* * Note: errors ignored, because the these special dirs, used for * space accounting, are only created on demand. */ (void) dsl_pool_open_special_dir(dp, LEAK_DIR_NAME, &dp->dp_leak_dir); if (spa_feature_is_active(dp->dp_spa, SPA_FEATURE_ASYNC_DESTROY)) { err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_BPTREE_OBJ, sizeof (uint64_t), 1, &dp->dp_bptree_obj); if (err != 0) goto out; } if (spa_feature_is_active(dp->dp_spa, SPA_FEATURE_EMPTY_BPOBJ)) { err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_EMPTY_BPOBJ, sizeof (uint64_t), 1, &dp->dp_empty_bpobj); if (err != 0) goto out; } err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_TMP_USERREFS, sizeof (uint64_t), 1, &dp->dp_tmp_userrefs_obj); if (err == ENOENT) err = 0; if (err) goto out; err = dsl_scan_init(dp, dp->dp_tx.tx_open_txg); out: rrw_exit(&dp->dp_config_rwlock, FTAG); return (err); } void dsl_pool_close(dsl_pool_t *dp) { /* * Drop our references from dsl_pool_open(). * * Since we held the origin_snap from "syncing" context (which * includes pool-opening context), it actually only got a "ref" * and not a hold, so just drop that here. */ if (dp->dp_origin_snap != NULL) dsl_dataset_rele(dp->dp_origin_snap, dp); if (dp->dp_mos_dir != NULL) dsl_dir_rele(dp->dp_mos_dir, dp); if (dp->dp_free_dir != NULL) dsl_dir_rele(dp->dp_free_dir, dp); if (dp->dp_leak_dir != NULL) dsl_dir_rele(dp->dp_leak_dir, dp); if (dp->dp_root_dir != NULL) dsl_dir_rele(dp->dp_root_dir, dp); bpobj_close(&dp->dp_free_bpobj); bpobj_close(&dp->dp_obsolete_bpobj); /* undo the dmu_objset_open_impl(mos) from dsl_pool_open() */ if (dp->dp_meta_objset != NULL) dmu_objset_evict(dp->dp_meta_objset); txg_list_destroy(&dp->dp_dirty_datasets); txg_list_destroy(&dp->dp_dirty_zilogs); txg_list_destroy(&dp->dp_sync_tasks); txg_list_destroy(&dp->dp_early_sync_tasks); txg_list_destroy(&dp->dp_dirty_dirs); taskq_destroy(dp->dp_zil_clean_taskq); taskq_destroy(dp->dp_sync_taskq); /* * We can't set retry to TRUE since we're explicitly specifying * a spa to flush. This is good enough; any missed buffers for * this spa won't cause trouble, and they'll eventually fall * out of the ARC just like any other unused buffer. */ arc_flush(dp->dp_spa, FALSE); txg_fini(dp); dsl_scan_fini(dp); dmu_buf_user_evict_wait(); rrw_destroy(&dp->dp_config_rwlock); mutex_destroy(&dp->dp_lock); taskq_destroy(dp->dp_vnrele_taskq); if (dp->dp_blkstats != NULL) { mutex_destroy(&dp->dp_blkstats->zab_lock); kmem_free(dp->dp_blkstats, sizeof (zfs_all_blkstats_t)); } kmem_free(dp, sizeof (dsl_pool_t)); } void dsl_pool_create_obsolete_bpobj(dsl_pool_t *dp, dmu_tx_t *tx) { uint64_t obj; /* * Currently, we only create the obsolete_bpobj where there are * indirect vdevs with referenced mappings. */ ASSERT(spa_feature_is_active(dp->dp_spa, SPA_FEATURE_DEVICE_REMOVAL)); /* create and open the obsolete_bpobj */ obj = bpobj_alloc(dp->dp_meta_objset, SPA_OLD_MAXBLOCKSIZE, tx); VERIFY0(bpobj_open(&dp->dp_obsolete_bpobj, dp->dp_meta_objset, obj)); VERIFY0(zap_add(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_OBSOLETE_BPOBJ, sizeof (uint64_t), 1, &obj, tx)); spa_feature_incr(dp->dp_spa, SPA_FEATURE_OBSOLETE_COUNTS, tx); } void dsl_pool_destroy_obsolete_bpobj(dsl_pool_t *dp, dmu_tx_t *tx) { spa_feature_decr(dp->dp_spa, SPA_FEATURE_OBSOLETE_COUNTS, tx); VERIFY0(zap_remove(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_OBSOLETE_BPOBJ, tx)); bpobj_free(dp->dp_meta_objset, dp->dp_obsolete_bpobj.bpo_object, tx); bpobj_close(&dp->dp_obsolete_bpobj); } dsl_pool_t * dsl_pool_create(spa_t *spa, nvlist_t *zplprops, uint64_t txg) { int err; dsl_pool_t *dp = dsl_pool_open_impl(spa, txg); dmu_tx_t *tx = dmu_tx_create_assigned(dp, txg); dsl_dataset_t *ds; uint64_t obj; rrw_enter(&dp->dp_config_rwlock, RW_WRITER, FTAG); /* create and open the MOS (meta-objset) */ dp->dp_meta_objset = dmu_objset_create_impl(spa, NULL, &dp->dp_meta_rootbp, DMU_OST_META, tx); /* create the pool directory */ err = zap_create_claim(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT, DMU_OT_OBJECT_DIRECTORY, DMU_OT_NONE, 0, tx); ASSERT0(err); /* Initialize scan structures */ VERIFY0(dsl_scan_init(dp, txg)); /* create and open the root dir */ dp->dp_root_dir_obj = dsl_dir_create_sync(dp, NULL, NULL, tx); VERIFY0(dsl_dir_hold_obj(dp, dp->dp_root_dir_obj, NULL, dp, &dp->dp_root_dir)); /* create and open the meta-objset dir */ (void) dsl_dir_create_sync(dp, dp->dp_root_dir, MOS_DIR_NAME, tx); VERIFY0(dsl_pool_open_special_dir(dp, MOS_DIR_NAME, &dp->dp_mos_dir)); if (spa_version(spa) >= SPA_VERSION_DEADLISTS) { /* create and open the free dir */ (void) dsl_dir_create_sync(dp, dp->dp_root_dir, FREE_DIR_NAME, tx); VERIFY0(dsl_pool_open_special_dir(dp, FREE_DIR_NAME, &dp->dp_free_dir)); /* create and open the free_bplist */ obj = bpobj_alloc(dp->dp_meta_objset, SPA_OLD_MAXBLOCKSIZE, tx); VERIFY(zap_add(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_FREE_BPOBJ, sizeof (uint64_t), 1, &obj, tx) == 0); VERIFY0(bpobj_open(&dp->dp_free_bpobj, dp->dp_meta_objset, obj)); } if (spa_version(spa) >= SPA_VERSION_DSL_SCRUB) dsl_pool_create_origin(dp, tx); /* create the root dataset */ obj = dsl_dataset_create_sync_dd(dp->dp_root_dir, NULL, 0, tx); /* create the root objset */ VERIFY0(dsl_dataset_hold_obj(dp, obj, FTAG, &ds)); #ifdef _KERNEL { objset_t *os; rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); os = dmu_objset_create_impl(dp->dp_spa, ds, dsl_dataset_get_blkptr(ds), DMU_OST_ZFS, tx); rrw_exit(&ds->ds_bp_rwlock, FTAG); zfs_create_fs(os, kcred, zplprops, tx); } #endif dsl_dataset_rele(ds, FTAG); dmu_tx_commit(tx); rrw_exit(&dp->dp_config_rwlock, FTAG); return (dp); } /* * Account for the meta-objset space in its placeholder dsl_dir. */ void dsl_pool_mos_diduse_space(dsl_pool_t *dp, int64_t used, int64_t comp, int64_t uncomp) { ASSERT3U(comp, ==, uncomp); /* it's all metadata */ mutex_enter(&dp->dp_lock); dp->dp_mos_used_delta += used; dp->dp_mos_compressed_delta += comp; dp->dp_mos_uncompressed_delta += uncomp; mutex_exit(&dp->dp_lock); } static void dsl_pool_sync_mos(dsl_pool_t *dp, dmu_tx_t *tx) { zio_t *zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED); dmu_objset_sync(dp->dp_meta_objset, zio, tx); VERIFY0(zio_wait(zio)); dprintf_bp(&dp->dp_meta_rootbp, "meta objset rootbp is %s", ""); spa_set_rootblkptr(dp->dp_spa, &dp->dp_meta_rootbp); } static void dsl_pool_dirty_delta(dsl_pool_t *dp, int64_t delta) { ASSERT(MUTEX_HELD(&dp->dp_lock)); if (delta < 0) ASSERT3U(-delta, <=, dp->dp_dirty_total); dp->dp_dirty_total += delta; /* * Note: we signal even when increasing dp_dirty_total. * This ensures forward progress -- each thread wakes the next waiter. */ if (dp->dp_dirty_total < zfs_dirty_data_max) cv_signal(&dp->dp_spaceavail_cv); } static boolean_t dsl_early_sync_task_verify(dsl_pool_t *dp, uint64_t txg) { spa_t *spa = dp->dp_spa; vdev_t *rvd = spa->spa_root_vdev; for (uint64_t c = 0; c < rvd->vdev_children; c++) { vdev_t *vd = rvd->vdev_child[c]; txg_list_t *tl = &vd->vdev_ms_list; metaslab_t *ms; for (ms = txg_list_head(tl, TXG_CLEAN(txg)); ms; ms = txg_list_next(tl, ms, TXG_CLEAN(txg))) { VERIFY(range_tree_is_empty(ms->ms_freeing)); VERIFY(range_tree_is_empty(ms->ms_checkpointing)); } } return (B_TRUE); } void dsl_pool_sync(dsl_pool_t *dp, uint64_t txg) { zio_t *zio; dmu_tx_t *tx; dsl_dir_t *dd; dsl_dataset_t *ds; objset_t *mos = dp->dp_meta_objset; list_t synced_datasets; list_create(&synced_datasets, sizeof (dsl_dataset_t), offsetof(dsl_dataset_t, ds_synced_link)); tx = dmu_tx_create_assigned(dp, txg); /* * Run all early sync tasks before writing out any dirty blocks. * For more info on early sync tasks see block comment in * dsl_early_sync_task(). */ if (!txg_list_empty(&dp->dp_early_sync_tasks, txg)) { dsl_sync_task_t *dst; ASSERT3U(spa_sync_pass(dp->dp_spa), ==, 1); while ((dst = txg_list_remove(&dp->dp_early_sync_tasks, txg)) != NULL) { ASSERT(dsl_early_sync_task_verify(dp, txg)); dsl_sync_task_sync(dst, tx); } ASSERT(dsl_early_sync_task_verify(dp, txg)); } /* * Write out all dirty blocks of dirty datasets. */ zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED); while ((ds = txg_list_remove(&dp->dp_dirty_datasets, txg)) != NULL) { /* * We must not sync any non-MOS datasets twice, because * we may have taken a snapshot of them. However, we * may sync newly-created datasets on pass 2. */ ASSERT(!list_link_active(&ds->ds_synced_link)); list_insert_tail(&synced_datasets, ds); dsl_dataset_sync(ds, zio, tx); } VERIFY0(zio_wait(zio)); /* * We have written all of the accounted dirty data, so our * dp_space_towrite should now be zero. However, some seldom-used * code paths do not adhere to this (e.g. dbuf_undirty(), also * rounding error in dbuf_write_physdone). * Shore up the accounting of any dirtied space now. */ dsl_pool_undirty_space(dp, dp->dp_dirty_pertxg[txg & TXG_MASK], txg); /* * Update the long range free counter after * we're done syncing user data */ mutex_enter(&dp->dp_lock); ASSERT(spa_sync_pass(dp->dp_spa) == 1 || dp->dp_long_free_dirty_pertxg[txg & TXG_MASK] == 0); dp->dp_long_free_dirty_pertxg[txg & TXG_MASK] = 0; mutex_exit(&dp->dp_lock); /* * After the data blocks have been written (ensured by the zio_wait() * above), update the user/group space accounting. This happens * in tasks dispatched to dp_sync_taskq, so wait for them before * continuing. */ for (ds = list_head(&synced_datasets); ds != NULL; ds = list_next(&synced_datasets, ds)) { dmu_objset_do_userquota_updates(ds->ds_objset, tx); } taskq_wait(dp->dp_sync_taskq); /* * Sync the datasets again to push out the changes due to * userspace updates. This must be done before we process the * sync tasks, so that any snapshots will have the correct * user accounting information (and we won't get confused * about which blocks are part of the snapshot). */ zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED); while ((ds = txg_list_remove(&dp->dp_dirty_datasets, txg)) != NULL) { ASSERT(list_link_active(&ds->ds_synced_link)); dmu_buf_rele(ds->ds_dbuf, ds); dsl_dataset_sync(ds, zio, tx); } VERIFY0(zio_wait(zio)); /* * Now that the datasets have been completely synced, we can * clean up our in-memory structures accumulated while syncing: * * - move dead blocks from the pending deadlist to the on-disk deadlist * - release hold from dsl_dataset_dirty() */ while ((ds = list_remove_head(&synced_datasets)) != NULL) { dsl_dataset_sync_done(ds, tx); } while ((dd = txg_list_remove(&dp->dp_dirty_dirs, txg)) != NULL) { dsl_dir_sync(dd, tx); } /* * The MOS's space is accounted for in the pool/$MOS * (dp_mos_dir). We can't modify the mos while we're syncing * it, so we remember the deltas and apply them here. */ if (dp->dp_mos_used_delta != 0 || dp->dp_mos_compressed_delta != 0 || dp->dp_mos_uncompressed_delta != 0) { dsl_dir_diduse_space(dp->dp_mos_dir, DD_USED_HEAD, dp->dp_mos_used_delta, dp->dp_mos_compressed_delta, dp->dp_mos_uncompressed_delta, tx); dp->dp_mos_used_delta = 0; dp->dp_mos_compressed_delta = 0; dp->dp_mos_uncompressed_delta = 0; } if (!multilist_is_empty(mos->os_dirty_dnodes[txg & TXG_MASK])) { dsl_pool_sync_mos(dp, tx); } /* * If we modify a dataset in the same txg that we want to destroy it, * its dsl_dir's dd_dbuf will be dirty, and thus have a hold on it. * dsl_dir_destroy_check() will fail if there are unexpected holds. * Therefore, we want to sync the MOS (thus syncing the dd_dbuf * and clearing the hold on it) before we process the sync_tasks. * The MOS data dirtied by the sync_tasks will be synced on the next * pass. */ if (!txg_list_empty(&dp->dp_sync_tasks, txg)) { dsl_sync_task_t *dst; /* * No more sync tasks should have been added while we * were syncing. */ ASSERT3U(spa_sync_pass(dp->dp_spa), ==, 1); while ((dst = txg_list_remove(&dp->dp_sync_tasks, txg)) != NULL) dsl_sync_task_sync(dst, tx); } dmu_tx_commit(tx); DTRACE_PROBE2(dsl_pool_sync__done, dsl_pool_t *dp, dp, uint64_t, txg); } void dsl_pool_sync_done(dsl_pool_t *dp, uint64_t txg) { zilog_t *zilog; while (zilog = txg_list_head(&dp->dp_dirty_zilogs, txg)) { dsl_dataset_t *ds = dmu_objset_ds(zilog->zl_os); /* * We don't remove the zilog from the dp_dirty_zilogs * list until after we've cleaned it. This ensures that * callers of zilog_is_dirty() receive an accurate * answer when they are racing with the spa sync thread. */ zil_clean(zilog, txg); (void) txg_list_remove_this(&dp->dp_dirty_zilogs, zilog, txg); ASSERT(!dmu_objset_is_dirty(zilog->zl_os, txg)); dmu_buf_rele(ds->ds_dbuf, zilog); } ASSERT(!dmu_objset_is_dirty(dp->dp_meta_objset, txg)); } /* * TRUE if the current thread is the tx_sync_thread or if we * are being called from SPA context during pool initialization. */ int dsl_pool_sync_context(dsl_pool_t *dp) { return (curthread == dp->dp_tx.tx_sync_thread || spa_is_initializing(dp->dp_spa) || taskq_member(dp->dp_sync_taskq, curthread)); } /* * This function returns the amount of allocatable space in the pool * minus whatever space is currently reserved by ZFS for specific * purposes. Specifically: * * 1] Any reserved SLOP space * 2] Any space used by the checkpoint * 3] Any space used for deferred frees * * The latter 2 are especially important because they are needed to * rectify the SPA's and DMU's different understanding of how much space * is used. Now the DMU is aware of that extra space tracked by the SPA * without having to maintain a separate special dir (e.g similar to * $MOS, $FREEING, and $LEAKED). * * Note: By deferred frees here, we mean the frees that were deferred * in spa_sync() after sync pass 1 (spa_deferred_bpobj), and not the * segments placed in ms_defer trees during metaslab_sync_done(). */ uint64_t dsl_pool_adjustedsize(dsl_pool_t *dp, zfs_space_check_t slop_policy) { spa_t *spa = dp->dp_spa; uint64_t space, resv, adjustedsize; uint64_t spa_deferred_frees = spa->spa_deferred_bpobj.bpo_phys->bpo_bytes; space = spa_get_dspace(spa) - spa_get_checkpoint_space(spa) - spa_deferred_frees; resv = spa_get_slop_space(spa); switch (slop_policy) { case ZFS_SPACE_CHECK_NORMAL: break; case ZFS_SPACE_CHECK_RESERVED: resv >>= 1; break; case ZFS_SPACE_CHECK_EXTRA_RESERVED: resv >>= 2; break; case ZFS_SPACE_CHECK_NONE: resv = 0; break; default: panic("invalid slop policy value: %d", slop_policy); break; } adjustedsize = (space >= resv) ? (space - resv) : 0; return (adjustedsize); } uint64_t dsl_pool_unreserved_space(dsl_pool_t *dp, zfs_space_check_t slop_policy) { uint64_t poolsize = dsl_pool_adjustedsize(dp, slop_policy); uint64_t deferred = metaslab_class_get_deferred(spa_normal_class(dp->dp_spa)); uint64_t quota = (poolsize >= deferred) ? (poolsize - deferred) : 0; return (quota); } boolean_t dsl_pool_need_dirty_delay(dsl_pool_t *dp) { uint64_t delay_min_bytes = zfs_dirty_data_max * zfs_delay_min_dirty_percent / 100; + uint64_t dirty_min_bytes = + zfs_dirty_data_max * zfs_dirty_data_sync_pct / 100; boolean_t rv; mutex_enter(&dp->dp_lock); - if (dp->dp_dirty_total > zfs_dirty_data_sync) + if (dp->dp_dirty_total > dirty_min_bytes) txg_kick(dp); rv = (dp->dp_dirty_total > delay_min_bytes); mutex_exit(&dp->dp_lock); return (rv); } void dsl_pool_dirty_space(dsl_pool_t *dp, int64_t space, dmu_tx_t *tx) { if (space > 0) { mutex_enter(&dp->dp_lock); dp->dp_dirty_pertxg[tx->tx_txg & TXG_MASK] += space; dsl_pool_dirty_delta(dp, space); mutex_exit(&dp->dp_lock); } } void dsl_pool_undirty_space(dsl_pool_t *dp, int64_t space, uint64_t txg) { ASSERT3S(space, >=, 0); if (space == 0) return; mutex_enter(&dp->dp_lock); if (dp->dp_dirty_pertxg[txg & TXG_MASK] < space) { /* XXX writing something we didn't dirty? */ space = dp->dp_dirty_pertxg[txg & TXG_MASK]; } ASSERT3U(dp->dp_dirty_pertxg[txg & TXG_MASK], >=, space); dp->dp_dirty_pertxg[txg & TXG_MASK] -= space; ASSERT3U(dp->dp_dirty_total, >=, space); dsl_pool_dirty_delta(dp, -space); mutex_exit(&dp->dp_lock); } /* ARGSUSED */ static int upgrade_clones_cb(dsl_pool_t *dp, dsl_dataset_t *hds, void *arg) { dmu_tx_t *tx = arg; dsl_dataset_t *ds, *prev = NULL; int err; err = dsl_dataset_hold_obj(dp, hds->ds_object, FTAG, &ds); if (err) return (err); while (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0) { err = dsl_dataset_hold_obj(dp, dsl_dataset_phys(ds)->ds_prev_snap_obj, FTAG, &prev); if (err) { dsl_dataset_rele(ds, FTAG); return (err); } if (dsl_dataset_phys(prev)->ds_next_snap_obj != ds->ds_object) break; dsl_dataset_rele(ds, FTAG); ds = prev; prev = NULL; } if (prev == NULL) { prev = dp->dp_origin_snap; /* * The $ORIGIN can't have any data, or the accounting * will be wrong. */ rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG); ASSERT0(dsl_dataset_phys(prev)->ds_bp.blk_birth); rrw_exit(&ds->ds_bp_rwlock, FTAG); /* The origin doesn't get attached to itself */ if (ds->ds_object == prev->ds_object) { dsl_dataset_rele(ds, FTAG); return (0); } dmu_buf_will_dirty(ds->ds_dbuf, tx); dsl_dataset_phys(ds)->ds_prev_snap_obj = prev->ds_object; dsl_dataset_phys(ds)->ds_prev_snap_txg = dsl_dataset_phys(prev)->ds_creation_txg; dmu_buf_will_dirty(ds->ds_dir->dd_dbuf, tx); dsl_dir_phys(ds->ds_dir)->dd_origin_obj = prev->ds_object; dmu_buf_will_dirty(prev->ds_dbuf, tx); dsl_dataset_phys(prev)->ds_num_children++; if (dsl_dataset_phys(ds)->ds_next_snap_obj == 0) { ASSERT(ds->ds_prev == NULL); VERIFY0(dsl_dataset_hold_obj(dp, dsl_dataset_phys(ds)->ds_prev_snap_obj, ds, &ds->ds_prev)); } } ASSERT3U(dsl_dir_phys(ds->ds_dir)->dd_origin_obj, ==, prev->ds_object); ASSERT3U(dsl_dataset_phys(ds)->ds_prev_snap_obj, ==, prev->ds_object); if (dsl_dataset_phys(prev)->ds_next_clones_obj == 0) { dmu_buf_will_dirty(prev->ds_dbuf, tx); dsl_dataset_phys(prev)->ds_next_clones_obj = zap_create(dp->dp_meta_objset, DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx); } VERIFY0(zap_add_int(dp->dp_meta_objset, dsl_dataset_phys(prev)->ds_next_clones_obj, ds->ds_object, tx)); dsl_dataset_rele(ds, FTAG); if (prev != dp->dp_origin_snap) dsl_dataset_rele(prev, FTAG); return (0); } void dsl_pool_upgrade_clones(dsl_pool_t *dp, dmu_tx_t *tx) { ASSERT(dmu_tx_is_syncing(tx)); ASSERT(dp->dp_origin_snap != NULL); VERIFY0(dmu_objset_find_dp(dp, dp->dp_root_dir_obj, upgrade_clones_cb, tx, DS_FIND_CHILDREN | DS_FIND_SERIALIZE)); } /* ARGSUSED */ static int upgrade_dir_clones_cb(dsl_pool_t *dp, dsl_dataset_t *ds, void *arg) { dmu_tx_t *tx = arg; objset_t *mos = dp->dp_meta_objset; if (dsl_dir_phys(ds->ds_dir)->dd_origin_obj != 0) { dsl_dataset_t *origin; VERIFY0(dsl_dataset_hold_obj(dp, dsl_dir_phys(ds->ds_dir)->dd_origin_obj, FTAG, &origin)); if (dsl_dir_phys(origin->ds_dir)->dd_clones == 0) { dmu_buf_will_dirty(origin->ds_dir->dd_dbuf, tx); dsl_dir_phys(origin->ds_dir)->dd_clones = zap_create(mos, DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx); } VERIFY0(zap_add_int(dp->dp_meta_objset, dsl_dir_phys(origin->ds_dir)->dd_clones, ds->ds_object, tx)); dsl_dataset_rele(origin, FTAG); } return (0); } void dsl_pool_upgrade_dir_clones(dsl_pool_t *dp, dmu_tx_t *tx) { ASSERT(dmu_tx_is_syncing(tx)); uint64_t obj; (void) dsl_dir_create_sync(dp, dp->dp_root_dir, FREE_DIR_NAME, tx); VERIFY0(dsl_pool_open_special_dir(dp, FREE_DIR_NAME, &dp->dp_free_dir)); /* * We can't use bpobj_alloc(), because spa_version() still * returns the old version, and we need a new-version bpobj with * subobj support. So call dmu_object_alloc() directly. */ obj = dmu_object_alloc(dp->dp_meta_objset, DMU_OT_BPOBJ, SPA_OLD_MAXBLOCKSIZE, DMU_OT_BPOBJ_HDR, sizeof (bpobj_phys_t), tx); VERIFY0(zap_add(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_FREE_BPOBJ, sizeof (uint64_t), 1, &obj, tx)); VERIFY0(bpobj_open(&dp->dp_free_bpobj, dp->dp_meta_objset, obj)); VERIFY0(dmu_objset_find_dp(dp, dp->dp_root_dir_obj, upgrade_dir_clones_cb, tx, DS_FIND_CHILDREN | DS_FIND_SERIALIZE)); } void dsl_pool_create_origin(dsl_pool_t *dp, dmu_tx_t *tx) { uint64_t dsobj; dsl_dataset_t *ds; ASSERT(dmu_tx_is_syncing(tx)); ASSERT(dp->dp_origin_snap == NULL); ASSERT(rrw_held(&dp->dp_config_rwlock, RW_WRITER)); /* create the origin dir, ds, & snap-ds */ dsobj = dsl_dataset_create_sync(dp->dp_root_dir, ORIGIN_DIR_NAME, NULL, 0, kcred, tx); VERIFY0(dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds)); dsl_dataset_snapshot_sync_impl(ds, ORIGIN_DIR_NAME, tx); VERIFY0(dsl_dataset_hold_obj(dp, dsl_dataset_phys(ds)->ds_prev_snap_obj, dp, &dp->dp_origin_snap)); dsl_dataset_rele(ds, FTAG); } taskq_t * dsl_pool_vnrele_taskq(dsl_pool_t *dp) { return (dp->dp_vnrele_taskq); } /* * Walk through the pool-wide zap object of temporary snapshot user holds * and release them. */ void dsl_pool_clean_tmp_userrefs(dsl_pool_t *dp) { zap_attribute_t za; zap_cursor_t zc; objset_t *mos = dp->dp_meta_objset; uint64_t zapobj = dp->dp_tmp_userrefs_obj; nvlist_t *holds; if (zapobj == 0) return; ASSERT(spa_version(dp->dp_spa) >= SPA_VERSION_USERREFS); holds = fnvlist_alloc(); for (zap_cursor_init(&zc, mos, zapobj); zap_cursor_retrieve(&zc, &za) == 0; zap_cursor_advance(&zc)) { char *htag; nvlist_t *tags; htag = strchr(za.za_name, '-'); *htag = '\0'; ++htag; if (nvlist_lookup_nvlist(holds, za.za_name, &tags) != 0) { tags = fnvlist_alloc(); fnvlist_add_boolean(tags, htag); fnvlist_add_nvlist(holds, za.za_name, tags); fnvlist_free(tags); } else { fnvlist_add_boolean(tags, htag); } } dsl_dataset_user_release_tmp(dp, holds); fnvlist_free(holds); zap_cursor_fini(&zc); } /* * Create the pool-wide zap object for storing temporary snapshot holds. */ void dsl_pool_user_hold_create_obj(dsl_pool_t *dp, dmu_tx_t *tx) { objset_t *mos = dp->dp_meta_objset; ASSERT(dp->dp_tmp_userrefs_obj == 0); ASSERT(dmu_tx_is_syncing(tx)); dp->dp_tmp_userrefs_obj = zap_create_link(mos, DMU_OT_USERREFS, DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_TMP_USERREFS, tx); } static int dsl_pool_user_hold_rele_impl(dsl_pool_t *dp, uint64_t dsobj, const char *tag, uint64_t now, dmu_tx_t *tx, boolean_t holding) { objset_t *mos = dp->dp_meta_objset; uint64_t zapobj = dp->dp_tmp_userrefs_obj; char *name; int error; ASSERT(spa_version(dp->dp_spa) >= SPA_VERSION_USERREFS); ASSERT(dmu_tx_is_syncing(tx)); /* * If the pool was created prior to SPA_VERSION_USERREFS, the * zap object for temporary holds might not exist yet. */ if (zapobj == 0) { if (holding) { dsl_pool_user_hold_create_obj(dp, tx); zapobj = dp->dp_tmp_userrefs_obj; } else { return (SET_ERROR(ENOENT)); } } name = kmem_asprintf("%llx-%s", (u_longlong_t)dsobj, tag); if (holding) error = zap_add(mos, zapobj, name, 8, 1, &now, tx); else error = zap_remove(mos, zapobj, name, tx); strfree(name); return (error); } /* * Add a temporary hold for the given dataset object and tag. */ int dsl_pool_user_hold(dsl_pool_t *dp, uint64_t dsobj, const char *tag, uint64_t now, dmu_tx_t *tx) { return (dsl_pool_user_hold_rele_impl(dp, dsobj, tag, now, tx, B_TRUE)); } /* * Release a temporary hold for the given dataset object and tag. */ int dsl_pool_user_release(dsl_pool_t *dp, uint64_t dsobj, const char *tag, dmu_tx_t *tx) { return (dsl_pool_user_hold_rele_impl(dp, dsobj, tag, 0, tx, B_FALSE)); } /* * DSL Pool Configuration Lock * * The dp_config_rwlock protects against changes to DSL state (e.g. dataset * creation / destruction / rename / property setting). It must be held for * read to hold a dataset or dsl_dir. I.e. you must call * dsl_pool_config_enter() or dsl_pool_hold() before calling * dsl_{dataset,dir}_hold{_obj}. In most circumstances, the dp_config_rwlock * must be held continuously until all datasets and dsl_dirs are released. * * The only exception to this rule is that if a "long hold" is placed on * a dataset, then the dp_config_rwlock may be dropped while the dataset * is still held. The long hold will prevent the dataset from being * destroyed -- the destroy will fail with EBUSY. A long hold can be * obtained by calling dsl_dataset_long_hold(), or by "owning" a dataset * (by calling dsl_{dataset,objset}_{try}own{_obj}). * * Legitimate long-holders (including owners) should be long-running, cancelable * tasks that should cause "zfs destroy" to fail. This includes DMU * consumers (i.e. a ZPL filesystem being mounted or ZVOL being open), * "zfs send", and "zfs diff". There are several other long-holders whose * uses are suboptimal (e.g. "zfs promote", and zil_suspend()). * * The usual formula for long-holding would be: * dsl_pool_hold() * dsl_dataset_hold() * ... perform checks ... * dsl_dataset_long_hold() * dsl_pool_rele() * ... perform long-running task ... * dsl_dataset_long_rele() * dsl_dataset_rele() * * Note that when the long hold is released, the dataset is still held but * the pool is not held. The dataset may change arbitrarily during this time * (e.g. it could be destroyed). Therefore you shouldn't do anything to the * dataset except release it. * * User-initiated operations (e.g. ioctls, zfs_ioc_*()) are either read-only * or modifying operations. * * Modifying operations should generally use dsl_sync_task(). The synctask * infrastructure enforces proper locking strategy with respect to the * dp_config_rwlock. See the comment above dsl_sync_task() for details. * * Read-only operations will manually hold the pool, then the dataset, obtain * information from the dataset, then release the pool and dataset. * dmu_objset_{hold,rele}() are convenience routines that also do the pool * hold/rele. */ int dsl_pool_hold(const char *name, void *tag, dsl_pool_t **dp) { spa_t *spa; int error; error = spa_open(name, &spa, tag); if (error == 0) { *dp = spa_get_dsl(spa); dsl_pool_config_enter(*dp, tag); } return (error); } void dsl_pool_rele(dsl_pool_t *dp, void *tag) { dsl_pool_config_exit(dp, tag); spa_close(dp->dp_spa, tag); } void dsl_pool_config_enter(dsl_pool_t *dp, void *tag) { /* * We use a "reentrant" reader-writer lock, but not reentrantly. * * The rrwlock can (with the track_all flag) track all reading threads, * which is very useful for debugging which code path failed to release * the lock, and for verifying that the *current* thread does hold * the lock. * * (Unlike a rwlock, which knows that N threads hold it for * read, but not *which* threads, so rw_held(RW_READER) returns TRUE * if any thread holds it for read, even if this thread doesn't). */ ASSERT(!rrw_held(&dp->dp_config_rwlock, RW_READER)); rrw_enter(&dp->dp_config_rwlock, RW_READER, tag); } void dsl_pool_config_enter_prio(dsl_pool_t *dp, void *tag) { ASSERT(!rrw_held(&dp->dp_config_rwlock, RW_READER)); rrw_enter_read_prio(&dp->dp_config_rwlock, tag); } void dsl_pool_config_exit(dsl_pool_t *dp, void *tag) { rrw_exit(&dp->dp_config_rwlock, tag); } boolean_t dsl_pool_config_held(dsl_pool_t *dp) { return (RRW_LOCK_HELD(&dp->dp_config_rwlock)); } boolean_t dsl_pool_config_held_writer(dsl_pool_t *dp) { return (RRW_WRITE_HELD(&dp->dp_config_rwlock)); } Index: stable/12/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_pool.h =================================================================== --- stable/12/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_pool.h (revision 348909) +++ stable/12/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_pool.h (revision 348910) @@ -1,190 +1,190 @@ /* * 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) 2005, 2010, Oracle and/or its affiliates. All rights reserved. * Copyright (c) 2013, 2017 by Delphix. All rights reserved. * Copyright 2016 Nexenta Systems, Inc. All rights reserved. */ #ifndef _SYS_DSL_POOL_H #define _SYS_DSL_POOL_H #include #include #include #include #include #include #include #include #include #include #include #include #ifdef __cplusplus extern "C" { #endif struct objset; struct dsl_dir; struct dsl_dataset; struct dsl_pool; struct dmu_tx; struct dsl_scan; extern uint64_t zfs_dirty_data_max; extern uint64_t zfs_dirty_data_max_max; -extern uint64_t zfs_dirty_data_sync; +extern uint64_t zfs_dirty_data_sync_pct; extern int zfs_dirty_data_max_percent; extern int zfs_delay_min_dirty_percent; extern uint64_t zfs_delay_scale; /* These macros are for indexing into the zfs_all_blkstats_t. */ #define DMU_OT_DEFERRED DMU_OT_NONE #define DMU_OT_OTHER DMU_OT_NUMTYPES /* place holder for DMU_OT() types */ #define DMU_OT_TOTAL (DMU_OT_NUMTYPES + 1) typedef struct zfs_blkstat { uint64_t zb_count; uint64_t zb_asize; uint64_t zb_lsize; uint64_t zb_psize; uint64_t zb_gangs; uint64_t zb_ditto_2_of_2_samevdev; uint64_t zb_ditto_2_of_3_samevdev; uint64_t zb_ditto_3_of_3_samevdev; } zfs_blkstat_t; typedef struct zfs_all_blkstats { zfs_blkstat_t zab_type[DN_MAX_LEVELS + 1][DMU_OT_TOTAL + 1]; kmutex_t zab_lock; } zfs_all_blkstats_t; typedef struct dsl_pool { /* Immutable */ spa_t *dp_spa; struct objset *dp_meta_objset; struct dsl_dir *dp_root_dir; struct dsl_dir *dp_mos_dir; struct dsl_dir *dp_free_dir; struct dsl_dir *dp_leak_dir; struct dsl_dataset *dp_origin_snap; uint64_t dp_root_dir_obj; struct taskq *dp_vnrele_taskq; /* No lock needed - sync context only */ blkptr_t dp_meta_rootbp; uint64_t dp_tmp_userrefs_obj; bpobj_t dp_free_bpobj; uint64_t dp_bptree_obj; uint64_t dp_empty_bpobj; bpobj_t dp_obsolete_bpobj; struct dsl_scan *dp_scan; /* Uses dp_lock */ kmutex_t dp_lock; kcondvar_t dp_spaceavail_cv; uint64_t dp_dirty_pertxg[TXG_SIZE]; uint64_t dp_dirty_total; uint64_t dp_long_free_dirty_pertxg[TXG_SIZE]; uint64_t dp_mos_used_delta; uint64_t dp_mos_compressed_delta; uint64_t dp_mos_uncompressed_delta; /* * Time of most recently scheduled (furthest in the future) * wakeup for delayed transactions. */ hrtime_t dp_last_wakeup; /* Has its own locking */ tx_state_t dp_tx; txg_list_t dp_dirty_datasets; txg_list_t dp_dirty_zilogs; txg_list_t dp_dirty_dirs; txg_list_t dp_sync_tasks; txg_list_t dp_early_sync_tasks; taskq_t *dp_sync_taskq; taskq_t *dp_zil_clean_taskq; /* * Protects administrative changes (properties, namespace) * * It is only held for write in syncing context. Therefore * syncing context does not need to ever have it for read, since * nobody else could possibly have it for write. */ rrwlock_t dp_config_rwlock; zfs_all_blkstats_t *dp_blkstats; } dsl_pool_t; int dsl_pool_init(spa_t *spa, uint64_t txg, dsl_pool_t **dpp); int dsl_pool_open(dsl_pool_t *dp); void dsl_pool_close(dsl_pool_t *dp); dsl_pool_t *dsl_pool_create(spa_t *spa, nvlist_t *zplprops, uint64_t txg); void dsl_pool_sync(dsl_pool_t *dp, uint64_t txg); void dsl_pool_sync_done(dsl_pool_t *dp, uint64_t txg); int dsl_pool_sync_context(dsl_pool_t *dp); uint64_t dsl_pool_adjustedsize(dsl_pool_t *dp, zfs_space_check_t slop_policy); uint64_t dsl_pool_unreserved_space(dsl_pool_t *dp, zfs_space_check_t slop_policy); void dsl_pool_dirty_space(dsl_pool_t *dp, int64_t space, dmu_tx_t *tx); void dsl_pool_undirty_space(dsl_pool_t *dp, int64_t space, uint64_t txg); void dsl_free(dsl_pool_t *dp, uint64_t txg, const blkptr_t *bpp); void dsl_free_sync(zio_t *pio, dsl_pool_t *dp, uint64_t txg, const blkptr_t *bpp); void dsl_pool_create_origin(dsl_pool_t *dp, dmu_tx_t *tx); void dsl_pool_upgrade_clones(dsl_pool_t *dp, dmu_tx_t *tx); void dsl_pool_upgrade_dir_clones(dsl_pool_t *dp, dmu_tx_t *tx); void dsl_pool_mos_diduse_space(dsl_pool_t *dp, int64_t used, int64_t comp, int64_t uncomp); void dsl_pool_ckpoint_diduse_space(dsl_pool_t *dp, int64_t used, int64_t comp, int64_t uncomp); void dsl_pool_config_enter(dsl_pool_t *dp, void *tag); void dsl_pool_config_enter_prio(dsl_pool_t *dp, void *tag); void dsl_pool_config_exit(dsl_pool_t *dp, void *tag); boolean_t dsl_pool_config_held(dsl_pool_t *dp); boolean_t dsl_pool_config_held_writer(dsl_pool_t *dp); boolean_t dsl_pool_need_dirty_delay(dsl_pool_t *dp); taskq_t *dsl_pool_vnrele_taskq(dsl_pool_t *dp); int dsl_pool_user_hold(dsl_pool_t *dp, uint64_t dsobj, const char *tag, uint64_t now, dmu_tx_t *tx); int dsl_pool_user_release(dsl_pool_t *dp, uint64_t dsobj, const char *tag, dmu_tx_t *tx); void dsl_pool_clean_tmp_userrefs(dsl_pool_t *dp); int dsl_pool_open_special_dir(dsl_pool_t *dp, const char *name, dsl_dir_t **); int dsl_pool_hold(const char *name, void *tag, dsl_pool_t **dp); void dsl_pool_rele(dsl_pool_t *dp, void *tag); void dsl_pool_create_obsolete_bpobj(dsl_pool_t *dp, dmu_tx_t *tx); void dsl_pool_destroy_obsolete_bpobj(dsl_pool_t *dp, dmu_tx_t *tx); #ifdef __cplusplus } #endif #endif /* _SYS_DSL_POOL_H */ Index: stable/12/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/txg.c =================================================================== --- stable/12/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/txg.c (revision 348909) +++ stable/12/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/txg.c (revision 348910) @@ -1,932 +1,934 @@ /* * 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) 2005, 2010, Oracle and/or its affiliates. All rights reserved. * Portions Copyright 2011 Martin Matuska * Copyright (c) 2012, 2017 by Delphix. All rights reserved. */ #include #include #include #include #include #include #include #include /* * ZFS Transaction Groups * ---------------------- * * ZFS transaction groups are, as the name implies, groups of transactions * that act on persistent state. ZFS asserts consistency at the granularity of * these transaction groups. Each successive transaction group (txg) is * assigned a 64-bit consecutive identifier. There are three active * transaction group states: open, quiescing, or syncing. At any given time, * there may be an active txg associated with each state; each active txg may * either be processing, or blocked waiting to enter the next state. There may * be up to three active txgs, and there is always a txg in the open state * (though it may be blocked waiting to enter the quiescing state). In broad * strokes, transactions -- operations that change in-memory structures -- are * accepted into the txg in the open state, and are completed while the txg is * in the open or quiescing states. The accumulated changes are written to * disk in the syncing state. * * Open * * When a new txg becomes active, it first enters the open state. New * transactions -- updates to in-memory structures -- are assigned to the * currently open txg. There is always a txg in the open state so that ZFS can * accept new changes (though the txg may refuse new changes if it has hit * some limit). ZFS advances the open txg to the next state for a variety of * reasons such as it hitting a time or size threshold, or the execution of an * administrative action that must be completed in the syncing state. * * Quiescing * * After a txg exits the open state, it enters the quiescing state. The * quiescing state is intended to provide a buffer between accepting new * transactions in the open state and writing them out to stable storage in * the syncing state. While quiescing, transactions can continue their * operation without delaying either of the other states. Typically, a txg is * in the quiescing state very briefly since the operations are bounded by * software latencies rather than, say, slower I/O latencies. After all * transactions complete, the txg is ready to enter the next state. * * Syncing * * In the syncing state, the in-memory state built up during the open and (to * a lesser degree) the quiescing states is written to stable storage. The * process of writing out modified data can, in turn modify more data. For * example when we write new blocks, we need to allocate space for them; those * allocations modify metadata (space maps)... which themselves must be * written to stable storage. During the sync state, ZFS iterates, writing out * data until it converges and all in-memory changes have been written out. * The first such pass is the largest as it encompasses all the modified user * data (as opposed to filesystem metadata). Subsequent passes typically have * far less data to write as they consist exclusively of filesystem metadata. * * To ensure convergence, after a certain number of passes ZFS begins * overwriting locations on stable storage that had been allocated earlier in * the syncing state (and subsequently freed). ZFS usually allocates new * blocks to optimize for large, continuous, writes. For the syncing state to * converge however it must complete a pass where no new blocks are allocated * since each allocation requires a modification of persistent metadata. * Further, to hasten convergence, after a prescribed number of passes, ZFS * also defers frees, and stops compressing. * * In addition to writing out user data, we must also execute synctasks during * the syncing context. A synctask is the mechanism by which some * administrative activities work such as creating and destroying snapshots or * datasets. Note that when a synctask is initiated it enters the open txg, * and ZFS then pushes that txg as quickly as possible to completion of the * syncing state in order to reduce the latency of the administrative * activity. To complete the syncing state, ZFS writes out a new uberblock, * the root of the tree of blocks that comprise all state stored on the ZFS * pool. Finally, if there is a quiesced txg waiting, we signal that it can * now transition to the syncing state. */ static void txg_sync_thread(void *arg); static void txg_quiesce_thread(void *arg); int zfs_txg_timeout = 5; /* max seconds worth of delta per txg */ SYSCTL_DECL(_vfs_zfs); SYSCTL_NODE(_vfs_zfs, OID_AUTO, txg, CTLFLAG_RW, 0, "ZFS TXG"); SYSCTL_INT(_vfs_zfs_txg, OID_AUTO, timeout, CTLFLAG_RWTUN, &zfs_txg_timeout, 0, "Maximum seconds worth of delta per txg"); /* * Prepare the txg subsystem. */ void txg_init(dsl_pool_t *dp, uint64_t txg) { tx_state_t *tx = &dp->dp_tx; int c; bzero(tx, sizeof (tx_state_t)); tx->tx_cpu = kmem_zalloc(max_ncpus * sizeof (tx_cpu_t), KM_SLEEP); for (c = 0; c < max_ncpus; c++) { int i; mutex_init(&tx->tx_cpu[c].tc_lock, NULL, MUTEX_DEFAULT, NULL); mutex_init(&tx->tx_cpu[c].tc_open_lock, NULL, MUTEX_DEFAULT, NULL); for (i = 0; i < TXG_SIZE; i++) { cv_init(&tx->tx_cpu[c].tc_cv[i], NULL, CV_DEFAULT, NULL); list_create(&tx->tx_cpu[c].tc_callbacks[i], sizeof (dmu_tx_callback_t), offsetof(dmu_tx_callback_t, dcb_node)); } } mutex_init(&tx->tx_sync_lock, NULL, MUTEX_DEFAULT, NULL); cv_init(&tx->tx_sync_more_cv, NULL, CV_DEFAULT, NULL); cv_init(&tx->tx_sync_done_cv, NULL, CV_DEFAULT, NULL); cv_init(&tx->tx_quiesce_more_cv, NULL, CV_DEFAULT, NULL); cv_init(&tx->tx_quiesce_done_cv, NULL, CV_DEFAULT, NULL); cv_init(&tx->tx_exit_cv, NULL, CV_DEFAULT, NULL); tx->tx_open_txg = txg; } /* * Close down the txg subsystem. */ void txg_fini(dsl_pool_t *dp) { tx_state_t *tx = &dp->dp_tx; int c; ASSERT0(tx->tx_threads); mutex_destroy(&tx->tx_sync_lock); cv_destroy(&tx->tx_sync_more_cv); cv_destroy(&tx->tx_sync_done_cv); cv_destroy(&tx->tx_quiesce_more_cv); cv_destroy(&tx->tx_quiesce_done_cv); cv_destroy(&tx->tx_exit_cv); for (c = 0; c < max_ncpus; c++) { int i; mutex_destroy(&tx->tx_cpu[c].tc_open_lock); mutex_destroy(&tx->tx_cpu[c].tc_lock); for (i = 0; i < TXG_SIZE; i++) { cv_destroy(&tx->tx_cpu[c].tc_cv[i]); list_destroy(&tx->tx_cpu[c].tc_callbacks[i]); } } if (tx->tx_commit_cb_taskq != NULL) taskq_destroy(tx->tx_commit_cb_taskq); kmem_free(tx->tx_cpu, max_ncpus * sizeof (tx_cpu_t)); bzero(tx, sizeof (tx_state_t)); } /* * Start syncing transaction groups. */ void txg_sync_start(dsl_pool_t *dp) { tx_state_t *tx = &dp->dp_tx; mutex_enter(&tx->tx_sync_lock); dprintf("pool %p\n", dp); ASSERT0(tx->tx_threads); tx->tx_threads = 2; tx->tx_quiesce_thread = thread_create(NULL, 0, txg_quiesce_thread, dp, 0, &p0, TS_RUN, minclsyspri); /* * The sync thread can need a larger-than-default stack size on * 32-bit x86. This is due in part to nested pools and * scrub_visitbp() recursion. */ tx->tx_sync_thread = thread_create(NULL, 32<<10, txg_sync_thread, dp, 0, &p0, TS_RUN, minclsyspri); mutex_exit(&tx->tx_sync_lock); } static void txg_thread_enter(tx_state_t *tx, callb_cpr_t *cpr) { CALLB_CPR_INIT(cpr, &tx->tx_sync_lock, callb_generic_cpr, FTAG); mutex_enter(&tx->tx_sync_lock); } static void txg_thread_exit(tx_state_t *tx, callb_cpr_t *cpr, kthread_t **tpp) { ASSERT(*tpp != NULL); *tpp = NULL; tx->tx_threads--; cv_broadcast(&tx->tx_exit_cv); CALLB_CPR_EXIT(cpr); /* drops &tx->tx_sync_lock */ thread_exit(); } static void txg_thread_wait(tx_state_t *tx, callb_cpr_t *cpr, kcondvar_t *cv, clock_t time) { CALLB_CPR_SAFE_BEGIN(cpr); if (time) (void) cv_timedwait(cv, &tx->tx_sync_lock, time); else cv_wait(cv, &tx->tx_sync_lock); CALLB_CPR_SAFE_END(cpr, &tx->tx_sync_lock); } /* * Stop syncing transaction groups. */ void txg_sync_stop(dsl_pool_t *dp) { tx_state_t *tx = &dp->dp_tx; dprintf("pool %p\n", dp); /* * Finish off any work in progress. */ ASSERT3U(tx->tx_threads, ==, 2); /* * We need to ensure that we've vacated the deferred space_maps. */ txg_wait_synced(dp, tx->tx_open_txg + TXG_DEFER_SIZE); /* * Wake all sync threads and wait for them to die. */ mutex_enter(&tx->tx_sync_lock); ASSERT3U(tx->tx_threads, ==, 2); tx->tx_exiting = 1; cv_broadcast(&tx->tx_quiesce_more_cv); cv_broadcast(&tx->tx_quiesce_done_cv); cv_broadcast(&tx->tx_sync_more_cv); while (tx->tx_threads != 0) cv_wait(&tx->tx_exit_cv, &tx->tx_sync_lock); tx->tx_exiting = 0; mutex_exit(&tx->tx_sync_lock); } uint64_t txg_hold_open(dsl_pool_t *dp, txg_handle_t *th) { tx_state_t *tx = &dp->dp_tx; tx_cpu_t *tc = &tx->tx_cpu[CPU_SEQID]; uint64_t txg; mutex_enter(&tc->tc_open_lock); txg = tx->tx_open_txg; mutex_enter(&tc->tc_lock); tc->tc_count[txg & TXG_MASK]++; mutex_exit(&tc->tc_lock); th->th_cpu = tc; th->th_txg = txg; return (txg); } void txg_rele_to_quiesce(txg_handle_t *th) { tx_cpu_t *tc = th->th_cpu; ASSERT(!MUTEX_HELD(&tc->tc_lock)); mutex_exit(&tc->tc_open_lock); } void txg_register_callbacks(txg_handle_t *th, list_t *tx_callbacks) { tx_cpu_t *tc = th->th_cpu; int g = th->th_txg & TXG_MASK; mutex_enter(&tc->tc_lock); list_move_tail(&tc->tc_callbacks[g], tx_callbacks); mutex_exit(&tc->tc_lock); } void txg_rele_to_sync(txg_handle_t *th) { tx_cpu_t *tc = th->th_cpu; int g = th->th_txg & TXG_MASK; mutex_enter(&tc->tc_lock); ASSERT(tc->tc_count[g] != 0); if (--tc->tc_count[g] == 0) cv_broadcast(&tc->tc_cv[g]); mutex_exit(&tc->tc_lock); th->th_cpu = NULL; /* defensive */ } /* * Blocks until all transactions in the group are committed. * * On return, the transaction group has reached a stable state in which it can * then be passed off to the syncing context. */ static __noinline void txg_quiesce(dsl_pool_t *dp, uint64_t txg) { tx_state_t *tx = &dp->dp_tx; int g = txg & TXG_MASK; int c; /* * Grab all tc_open_locks so nobody else can get into this txg. */ for (c = 0; c < max_ncpus; c++) mutex_enter(&tx->tx_cpu[c].tc_open_lock); ASSERT(txg == tx->tx_open_txg); tx->tx_open_txg++; tx->tx_open_time = gethrtime(); DTRACE_PROBE2(txg__quiescing, dsl_pool_t *, dp, uint64_t, txg); DTRACE_PROBE2(txg__opened, dsl_pool_t *, dp, uint64_t, tx->tx_open_txg); /* * Now that we've incremented tx_open_txg, we can let threads * enter the next transaction group. */ for (c = 0; c < max_ncpus; c++) mutex_exit(&tx->tx_cpu[c].tc_open_lock); /* * Quiesce the transaction group by waiting for everyone to txg_exit(). */ for (c = 0; c < max_ncpus; c++) { tx_cpu_t *tc = &tx->tx_cpu[c]; mutex_enter(&tc->tc_lock); while (tc->tc_count[g] != 0) cv_wait(&tc->tc_cv[g], &tc->tc_lock); mutex_exit(&tc->tc_lock); } } static void txg_do_callbacks(void *arg) { list_t *cb_list = arg; dmu_tx_do_callbacks(cb_list, 0); list_destroy(cb_list); kmem_free(cb_list, sizeof (list_t)); } /* * Dispatch the commit callbacks registered on this txg to worker threads. * * If no callbacks are registered for a given TXG, nothing happens. * This function creates a taskq for the associated pool, if needed. */ static void txg_dispatch_callbacks(dsl_pool_t *dp, uint64_t txg) { int c; tx_state_t *tx = &dp->dp_tx; list_t *cb_list; for (c = 0; c < max_ncpus; c++) { tx_cpu_t *tc = &tx->tx_cpu[c]; /* * No need to lock tx_cpu_t at this point, since this can * only be called once a txg has been synced. */ int g = txg & TXG_MASK; if (list_is_empty(&tc->tc_callbacks[g])) continue; if (tx->tx_commit_cb_taskq == NULL) { /* * Commit callback taskq hasn't been created yet. */ tx->tx_commit_cb_taskq = taskq_create("tx_commit_cb", max_ncpus, minclsyspri, max_ncpus, max_ncpus * 2, TASKQ_PREPOPULATE); } cb_list = kmem_alloc(sizeof (list_t), KM_SLEEP); list_create(cb_list, sizeof (dmu_tx_callback_t), offsetof(dmu_tx_callback_t, dcb_node)); list_move_tail(cb_list, &tc->tc_callbacks[g]); (void) taskq_dispatch(tx->tx_commit_cb_taskq, (task_func_t *) txg_do_callbacks, cb_list, TQ_SLEEP); } } static boolean_t txg_is_syncing(dsl_pool_t *dp) { tx_state_t *tx = &dp->dp_tx; ASSERT(MUTEX_HELD(&tx->tx_sync_lock)); return (tx->tx_syncing_txg != 0); } static boolean_t txg_is_quiescing(dsl_pool_t *dp) { tx_state_t *tx = &dp->dp_tx; ASSERT(MUTEX_HELD(&tx->tx_sync_lock)); return (tx->tx_quiescing_txg != 0); } static boolean_t txg_has_quiesced_to_sync(dsl_pool_t *dp) { tx_state_t *tx = &dp->dp_tx; ASSERT(MUTEX_HELD(&tx->tx_sync_lock)); return (tx->tx_quiesced_txg != 0); } static void txg_sync_thread(void *arg) { dsl_pool_t *dp = arg; spa_t *spa = dp->dp_spa; tx_state_t *tx = &dp->dp_tx; callb_cpr_t cpr; uint64_t start, delta; txg_thread_enter(tx, &cpr); start = delta = 0; for (;;) { uint64_t timeout = zfs_txg_timeout * hz; uint64_t timer; uint64_t txg; + uint64_t dirty_min_bytes = + zfs_dirty_data_max * zfs_dirty_data_sync_pct / 100; /* * We sync when we're scanning, there's someone waiting * on us, or the quiesce thread has handed off a txg to * us, or we have reached our timeout. */ timer = (delta >= timeout ? 0 : timeout - delta); while (!dsl_scan_active(dp->dp_scan) && !tx->tx_exiting && timer > 0 && tx->tx_synced_txg >= tx->tx_sync_txg_waiting && !txg_has_quiesced_to_sync(dp) && - dp->dp_dirty_total < zfs_dirty_data_sync) { + dp->dp_dirty_total < dirty_min_bytes) { dprintf("waiting; tx_synced=%llu waiting=%llu dp=%p\n", tx->tx_synced_txg, tx->tx_sync_txg_waiting, dp); txg_thread_wait(tx, &cpr, &tx->tx_sync_more_cv, timer); delta = ddi_get_lbolt() - start; timer = (delta > timeout ? 0 : timeout - delta); } /* * Wait until the quiesce thread hands off a txg to us, * prompting it to do so if necessary. */ while (!tx->tx_exiting && !txg_has_quiesced_to_sync(dp)) { if (tx->tx_quiesce_txg_waiting < tx->tx_open_txg+1) tx->tx_quiesce_txg_waiting = tx->tx_open_txg+1; cv_broadcast(&tx->tx_quiesce_more_cv); txg_thread_wait(tx, &cpr, &tx->tx_quiesce_done_cv, 0); } if (tx->tx_exiting) txg_thread_exit(tx, &cpr, &tx->tx_sync_thread); /* * Consume the quiesced txg which has been handed off to * us. This may cause the quiescing thread to now be * able to quiesce another txg, so we must signal it. */ ASSERT(tx->tx_quiesced_txg != 0); txg = tx->tx_quiesced_txg; tx->tx_quiesced_txg = 0; tx->tx_syncing_txg = txg; DTRACE_PROBE2(txg__syncing, dsl_pool_t *, dp, uint64_t, txg); cv_broadcast(&tx->tx_quiesce_more_cv); dprintf("txg=%llu quiesce_txg=%llu sync_txg=%llu\n", txg, tx->tx_quiesce_txg_waiting, tx->tx_sync_txg_waiting); mutex_exit(&tx->tx_sync_lock); start = ddi_get_lbolt(); spa_sync(spa, txg); delta = ddi_get_lbolt() - start; mutex_enter(&tx->tx_sync_lock); tx->tx_synced_txg = txg; tx->tx_syncing_txg = 0; DTRACE_PROBE2(txg__synced, dsl_pool_t *, dp, uint64_t, txg); cv_broadcast(&tx->tx_sync_done_cv); /* * Dispatch commit callbacks to worker threads. */ txg_dispatch_callbacks(dp, txg); } } static void txg_quiesce_thread(void *arg) { dsl_pool_t *dp = arg; tx_state_t *tx = &dp->dp_tx; callb_cpr_t cpr; txg_thread_enter(tx, &cpr); for (;;) { uint64_t txg; /* * We quiesce when there's someone waiting on us. * However, we can only have one txg in "quiescing" or * "quiesced, waiting to sync" state. So we wait until * the "quiesced, waiting to sync" txg has been consumed * by the sync thread. */ while (!tx->tx_exiting && (tx->tx_open_txg >= tx->tx_quiesce_txg_waiting || txg_has_quiesced_to_sync(dp))) txg_thread_wait(tx, &cpr, &tx->tx_quiesce_more_cv, 0); if (tx->tx_exiting) txg_thread_exit(tx, &cpr, &tx->tx_quiesce_thread); txg = tx->tx_open_txg; dprintf("txg=%llu quiesce_txg=%llu sync_txg=%llu\n", txg, tx->tx_quiesce_txg_waiting, tx->tx_sync_txg_waiting); tx->tx_quiescing_txg = txg; mutex_exit(&tx->tx_sync_lock); txg_quiesce(dp, txg); mutex_enter(&tx->tx_sync_lock); /* * Hand this txg off to the sync thread. */ dprintf("quiesce done, handing off txg %llu\n", txg); tx->tx_quiescing_txg = 0; tx->tx_quiesced_txg = txg; DTRACE_PROBE2(txg__quiesced, dsl_pool_t *, dp, uint64_t, txg); cv_broadcast(&tx->tx_sync_more_cv); cv_broadcast(&tx->tx_quiesce_done_cv); } } /* * Delay this thread by delay nanoseconds if we are still in the open * transaction group and there is already a waiting txg quiesing or quiesced. * Abort the delay if this txg stalls or enters the quiesing state. */ void txg_delay(dsl_pool_t *dp, uint64_t txg, hrtime_t delay, hrtime_t resolution) { tx_state_t *tx = &dp->dp_tx; hrtime_t start = gethrtime(); /* don't delay if this txg could transition to quiescing immediately */ if (tx->tx_open_txg > txg || tx->tx_syncing_txg == txg-1 || tx->tx_synced_txg == txg-1) return; mutex_enter(&tx->tx_sync_lock); if (tx->tx_open_txg > txg || tx->tx_synced_txg == txg-1) { mutex_exit(&tx->tx_sync_lock); return; } while (gethrtime() - start < delay && tx->tx_syncing_txg < txg-1 && !txg_stalled(dp)) { (void) cv_timedwait_hires(&tx->tx_quiesce_more_cv, &tx->tx_sync_lock, delay, resolution, 0); } mutex_exit(&tx->tx_sync_lock); } void txg_wait_synced(dsl_pool_t *dp, uint64_t txg) { tx_state_t *tx = &dp->dp_tx; ASSERT(!dsl_pool_config_held(dp)); mutex_enter(&tx->tx_sync_lock); ASSERT3U(tx->tx_threads, ==, 2); if (txg == 0) txg = tx->tx_open_txg + TXG_DEFER_SIZE; if (tx->tx_sync_txg_waiting < txg) tx->tx_sync_txg_waiting = txg; dprintf("txg=%llu quiesce_txg=%llu sync_txg=%llu\n", txg, tx->tx_quiesce_txg_waiting, tx->tx_sync_txg_waiting); while (tx->tx_synced_txg < txg) { dprintf("broadcasting sync more " "tx_synced=%llu waiting=%llu dp=%p\n", tx->tx_synced_txg, tx->tx_sync_txg_waiting, dp); cv_broadcast(&tx->tx_sync_more_cv); cv_wait(&tx->tx_sync_done_cv, &tx->tx_sync_lock); } mutex_exit(&tx->tx_sync_lock); } void txg_wait_open(dsl_pool_t *dp, uint64_t txg) { tx_state_t *tx = &dp->dp_tx; ASSERT(!dsl_pool_config_held(dp)); mutex_enter(&tx->tx_sync_lock); ASSERT3U(tx->tx_threads, ==, 2); if (txg == 0) txg = tx->tx_open_txg + 1; if (tx->tx_quiesce_txg_waiting < txg) tx->tx_quiesce_txg_waiting = txg; dprintf("txg=%llu quiesce_txg=%llu sync_txg=%llu\n", txg, tx->tx_quiesce_txg_waiting, tx->tx_sync_txg_waiting); while (tx->tx_open_txg < txg) { cv_broadcast(&tx->tx_quiesce_more_cv); cv_wait(&tx->tx_quiesce_done_cv, &tx->tx_sync_lock); } mutex_exit(&tx->tx_sync_lock); } /* * If there isn't a txg syncing or in the pipeline, push another txg through * the pipeline by queiscing the open txg. */ void txg_kick(dsl_pool_t *dp) { tx_state_t *tx = &dp->dp_tx; ASSERT(!dsl_pool_config_held(dp)); mutex_enter(&tx->tx_sync_lock); if (!txg_is_syncing(dp) && !txg_is_quiescing(dp) && tx->tx_quiesce_txg_waiting <= tx->tx_open_txg && tx->tx_sync_txg_waiting <= tx->tx_synced_txg && tx->tx_quiesced_txg <= tx->tx_synced_txg) { tx->tx_quiesce_txg_waiting = tx->tx_open_txg + 1; cv_broadcast(&tx->tx_quiesce_more_cv); } mutex_exit(&tx->tx_sync_lock); } boolean_t txg_stalled(dsl_pool_t *dp) { tx_state_t *tx = &dp->dp_tx; return (tx->tx_quiesce_txg_waiting > tx->tx_open_txg); } boolean_t txg_sync_waiting(dsl_pool_t *dp) { tx_state_t *tx = &dp->dp_tx; return (tx->tx_syncing_txg <= tx->tx_sync_txg_waiting || tx->tx_quiesced_txg != 0); } /* * Verify that this txg is active (open, quiescing, syncing). Non-active * txg's should not be manipulated. */ void txg_verify(spa_t *spa, uint64_t txg) { dsl_pool_t *dp = spa_get_dsl(spa); if (txg <= TXG_INITIAL || txg == ZILTEST_TXG) return; ASSERT3U(txg, <=, dp->dp_tx.tx_open_txg); ASSERT3U(txg, >=, dp->dp_tx.tx_synced_txg); ASSERT3U(txg, >=, dp->dp_tx.tx_open_txg - TXG_CONCURRENT_STATES); } /* * Per-txg object lists. */ void txg_list_create(txg_list_t *tl, spa_t *spa, size_t offset) { int t; mutex_init(&tl->tl_lock, NULL, MUTEX_DEFAULT, NULL); tl->tl_offset = offset; tl->tl_spa = spa; for (t = 0; t < TXG_SIZE; t++) tl->tl_head[t] = NULL; } void txg_list_destroy(txg_list_t *tl) { int t; for (t = 0; t < TXG_SIZE; t++) ASSERT(txg_list_empty(tl, t)); mutex_destroy(&tl->tl_lock); } boolean_t txg_list_empty(txg_list_t *tl, uint64_t txg) { txg_verify(tl->tl_spa, txg); return (tl->tl_head[txg & TXG_MASK] == NULL); } /* * Returns true if all txg lists are empty. * * Warning: this is inherently racy (an item could be added immediately * after this function returns). We don't bother with the lock because * it wouldn't change the semantics. */ boolean_t txg_all_lists_empty(txg_list_t *tl) { for (int i = 0; i < TXG_SIZE; i++) { if (!txg_list_empty(tl, i)) { return (B_FALSE); } } return (B_TRUE); } /* * Add an entry to the list (unless it's already on the list). * Returns B_TRUE if it was actually added. */ boolean_t txg_list_add(txg_list_t *tl, void *p, uint64_t txg) { int t = txg & TXG_MASK; txg_node_t *tn = (txg_node_t *)((char *)p + tl->tl_offset); boolean_t add; txg_verify(tl->tl_spa, txg); mutex_enter(&tl->tl_lock); add = (tn->tn_member[t] == 0); if (add) { tn->tn_member[t] = 1; tn->tn_next[t] = tl->tl_head[t]; tl->tl_head[t] = tn; } mutex_exit(&tl->tl_lock); return (add); } /* * Add an entry to the end of the list, unless it's already on the list. * (walks list to find end) * Returns B_TRUE if it was actually added. */ boolean_t txg_list_add_tail(txg_list_t *tl, void *p, uint64_t txg) { int t = txg & TXG_MASK; txg_node_t *tn = (txg_node_t *)((char *)p + tl->tl_offset); boolean_t add; txg_verify(tl->tl_spa, txg); mutex_enter(&tl->tl_lock); add = (tn->tn_member[t] == 0); if (add) { txg_node_t **tp; for (tp = &tl->tl_head[t]; *tp != NULL; tp = &(*tp)->tn_next[t]) continue; tn->tn_member[t] = 1; tn->tn_next[t] = NULL; *tp = tn; } mutex_exit(&tl->tl_lock); return (add); } /* * Remove the head of the list and return it. */ void * txg_list_remove(txg_list_t *tl, uint64_t txg) { int t = txg & TXG_MASK; txg_node_t *tn; void *p = NULL; txg_verify(tl->tl_spa, txg); mutex_enter(&tl->tl_lock); if ((tn = tl->tl_head[t]) != NULL) { ASSERT(tn->tn_member[t]); ASSERT(tn->tn_next[t] == NULL || tn->tn_next[t]->tn_member[t]); p = (char *)tn - tl->tl_offset; tl->tl_head[t] = tn->tn_next[t]; tn->tn_next[t] = NULL; tn->tn_member[t] = 0; } mutex_exit(&tl->tl_lock); return (p); } /* * Remove a specific item from the list and return it. */ void * txg_list_remove_this(txg_list_t *tl, void *p, uint64_t txg) { int t = txg & TXG_MASK; txg_node_t *tn, **tp; txg_verify(tl->tl_spa, txg); mutex_enter(&tl->tl_lock); for (tp = &tl->tl_head[t]; (tn = *tp) != NULL; tp = &tn->tn_next[t]) { if ((char *)tn - tl->tl_offset == p) { *tp = tn->tn_next[t]; tn->tn_next[t] = NULL; tn->tn_member[t] = 0; mutex_exit(&tl->tl_lock); return (p); } } mutex_exit(&tl->tl_lock); return (NULL); } boolean_t txg_list_member(txg_list_t *tl, void *p, uint64_t txg) { int t = txg & TXG_MASK; txg_node_t *tn = (txg_node_t *)((char *)p + tl->tl_offset); txg_verify(tl->tl_spa, txg); return (tn->tn_member[t] != 0); } /* * Walk a txg list -- only safe if you know it's not changing. */ void * txg_list_head(txg_list_t *tl, uint64_t txg) { int t = txg & TXG_MASK; txg_node_t *tn = tl->tl_head[t]; txg_verify(tl->tl_spa, txg); return (tn == NULL ? NULL : (char *)tn - tl->tl_offset); } void * txg_list_next(txg_list_t *tl, void *p, uint64_t txg) { int t = txg & TXG_MASK; txg_node_t *tn = (txg_node_t *)((char *)p + tl->tl_offset); txg_verify(tl->tl_spa, txg); tn = tn->tn_next[t]; return (tn == NULL ? NULL : (char *)tn - tl->tl_offset); } Index: stable/12 =================================================================== --- stable/12 (revision 348909) +++ stable/12 (revision 348910) Property changes on: stable/12 ___________________________________________________________________ Modified: svn:mergeinfo ## -0,0 +0,1 ## Merged /head:r348561