| /* |
| * 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, 2019 by Delphix. All rights reserved. |
| * Copyright (c) 2013 by Saso Kiselkov. All rights reserved. |
| * Copyright (c) 2017, Intel Corporation. |
| */ |
| |
| #include <sys/zfs_context.h> |
| #include <sys/dmu.h> |
| #include <sys/dmu_tx.h> |
| #include <sys/space_map.h> |
| #include <sys/metaslab_impl.h> |
| #include <sys/vdev_impl.h> |
| #include <sys/zio.h> |
| #include <sys/spa_impl.h> |
| #include <sys/zfeature.h> |
| #include <sys/vdev_indirect_mapping.h> |
| #include <sys/zap.h> |
| |
| #define WITH_DF_BLOCK_ALLOCATOR |
| |
| #define GANG_ALLOCATION(flags) \ |
| ((flags) & (METASLAB_GANG_CHILD | METASLAB_GANG_HEADER)) |
| |
| /* |
| * Metaslab granularity, in bytes. This is roughly similar to what would be |
| * referred to as the "stripe size" in traditional RAID arrays. In normal |
| * operation, we will try to write this amount of data to a top-level vdev |
| * before moving on to the next one. |
| */ |
| unsigned long metaslab_aliquot = 512 << 10; |
| |
| /* |
| * For testing, make some blocks above a certain size be gang blocks. |
| */ |
| unsigned long metaslab_force_ganging = SPA_MAXBLOCKSIZE + 1; |
| |
| /* |
| * Since we can touch multiple metaslabs (and their respective space maps) |
| * with each transaction group, we benefit from having a smaller space map |
| * block size since it allows us to issue more I/O operations scattered |
| * around the disk. |
| */ |
| int zfs_metaslab_sm_blksz = (1 << 12); |
| |
| /* |
| * The in-core space map representation is more compact than its on-disk form. |
| * The zfs_condense_pct determines how much more compact the in-core |
| * space map representation must be before we compact it on-disk. |
| * Values should be greater than or equal to 100. |
| */ |
| int zfs_condense_pct = 200; |
| |
| /* |
| * Condensing a metaslab is not guaranteed to actually reduce the amount of |
| * space used on disk. In particular, a space map uses data in increments of |
| * MAX(1 << ashift, space_map_blksz), so a metaslab might use the |
| * same number of blocks after condensing. Since the goal of condensing is to |
| * reduce the number of IOPs required to read the space map, we only want to |
| * condense when we can be sure we will reduce the number of blocks used by the |
| * space map. Unfortunately, we cannot precisely compute whether or not this is |
| * the case in metaslab_should_condense since we are holding ms_lock. Instead, |
| * we apply the following heuristic: do not condense a spacemap unless the |
| * uncondensed size consumes greater than zfs_metaslab_condense_block_threshold |
| * blocks. |
| */ |
| int zfs_metaslab_condense_block_threshold = 4; |
| |
| /* |
| * The zfs_mg_noalloc_threshold defines which metaslab groups should |
| * be eligible for allocation. The value is defined as a percentage of |
| * free space. Metaslab groups that have more free space than |
| * zfs_mg_noalloc_threshold are always eligible for allocations. Once |
| * a metaslab group's free space is less than or equal to the |
| * zfs_mg_noalloc_threshold the allocator will avoid allocating to that |
| * group unless all groups in the pool have reached zfs_mg_noalloc_threshold. |
| * Once all groups in the pool reach zfs_mg_noalloc_threshold then all |
| * groups are allowed to accept allocations. Gang blocks are always |
| * eligible to allocate on any metaslab group. The default value of 0 means |
| * no metaslab group will be excluded based on this criterion. |
| */ |
| int zfs_mg_noalloc_threshold = 0; |
| |
| /* |
| * Metaslab groups are considered eligible for allocations if their |
| * fragmenation metric (measured as a percentage) is less than or |
| * equal to zfs_mg_fragmentation_threshold. If a metaslab group |
| * exceeds this threshold then it will be skipped unless all metaslab |
| * groups within the metaslab class have also crossed this threshold. |
| * |
| * This tunable was introduced to avoid edge cases where we continue |
| * allocating from very fragmented disks in our pool while other, less |
| * fragmented disks, exists. On the other hand, if all disks in the |
| * pool are uniformly approaching the threshold, the threshold can |
| * be a speed bump in performance, where we keep switching the disks |
| * that we allocate from (e.g. we allocate some segments from disk A |
| * making it bypassing the threshold while freeing segments from disk |
| * B getting its fragmentation below the threshold). |
| * |
| * Empirically, we've seen that our vdev selection for allocations is |
| * good enough that fragmentation increases uniformly across all vdevs |
| * the majority of the time. Thus we set the threshold percentage high |
| * enough to avoid hitting the speed bump on pools that are being pushed |
| * to the edge. |
| */ |
| int zfs_mg_fragmentation_threshold = 95; |
| |
| /* |
| * Allow metaslabs to keep their active state as long as their fragmentation |
| * percentage is less than or equal to zfs_metaslab_fragmentation_threshold. An |
| * active metaslab that exceeds this threshold will no longer keep its active |
| * status allowing better metaslabs to be selected. |
| */ |
| int zfs_metaslab_fragmentation_threshold = 70; |
| |
| /* |
| * When set will load all metaslabs when pool is first opened. |
| */ |
| int metaslab_debug_load = 0; |
| |
| /* |
| * When set will prevent metaslabs from being unloaded. |
| */ |
| int metaslab_debug_unload = 0; |
| |
| /* |
| * Minimum size which forces the dynamic allocator to change |
| * it's allocation strategy. Once the space map cannot satisfy |
| * an allocation of this size then it switches to using more |
| * aggressive strategy (i.e search by size rather than offset). |
| */ |
| uint64_t metaslab_df_alloc_threshold = SPA_OLD_MAXBLOCKSIZE; |
| |
| /* |
| * The minimum free space, in percent, which must be available |
| * in a space map to continue allocations in a first-fit fashion. |
| * Once the space map's free space drops below this level we dynamically |
| * switch to using best-fit allocations. |
| */ |
| int metaslab_df_free_pct = 4; |
| |
| /* |
| * Maximum distance to search forward from the last offset. Without this |
| * limit, fragmented pools can see >100,000 iterations and |
| * metaslab_block_picker() becomes the performance limiting factor on |
| * high-performance storage. |
| * |
| * With the default setting of 16MB, we typically see less than 500 |
| * iterations, even with very fragmented, ashift=9 pools. The maximum number |
| * of iterations possible is: |
| * metaslab_df_max_search / (2 * (1<<ashift)) |
| * With the default setting of 16MB this is 16*1024 (with ashift=9) or |
| * 2048 (with ashift=12). |
| */ |
| int metaslab_df_max_search = 16 * 1024 * 1024; |
| |
| /* |
| * If we are not searching forward (due to metaslab_df_max_search, |
| * metaslab_df_free_pct, or metaslab_df_alloc_threshold), this tunable |
| * controls what segment is used. If it is set, we will use the largest free |
| * segment. If it is not set, we will use a segment of exactly the requested |
| * size (or larger). |
| */ |
| int metaslab_df_use_largest_segment = B_FALSE; |
| |
| /* |
| * Percentage of all cpus that can be used by the metaslab taskq. |
| */ |
| int metaslab_load_pct = 50; |
| |
| /* |
| * Determines how many txgs a metaslab may remain loaded without having any |
| * allocations from it. As long as a metaslab continues to be used we will |
| * keep it loaded. |
| */ |
| int metaslab_unload_delay = TXG_SIZE * 2; |
| |
| /* |
| * Max number of metaslabs per group to preload. |
| */ |
| int metaslab_preload_limit = SPA_DVAS_PER_BP; |
| |
| /* |
| * Enable/disable preloading of metaslab. |
| */ |
| int metaslab_preload_enabled = B_TRUE; |
| |
| /* |
| * Enable/disable fragmentation weighting on metaslabs. |
| */ |
| int metaslab_fragmentation_factor_enabled = B_TRUE; |
| |
| /* |
| * Enable/disable lba weighting (i.e. outer tracks are given preference). |
| */ |
| int metaslab_lba_weighting_enabled = B_TRUE; |
| |
| /* |
| * Enable/disable metaslab group biasing. |
| */ |
| int metaslab_bias_enabled = B_TRUE; |
| |
| /* |
| * Enable/disable remapping of indirect DVAs to their concrete vdevs. |
| */ |
| boolean_t zfs_remap_blkptr_enable = B_TRUE; |
| |
| /* |
| * Enable/disable segment-based metaslab selection. |
| */ |
| int zfs_metaslab_segment_weight_enabled = B_TRUE; |
| |
| /* |
| * When using segment-based metaslab selection, we will continue |
| * allocating from the active metaslab until we have exhausted |
| * zfs_metaslab_switch_threshold of its buckets. |
| */ |
| int zfs_metaslab_switch_threshold = 2; |
| |
| /* |
| * Internal switch to enable/disable the metaslab allocation tracing |
| * facility. |
| */ |
| #ifdef _METASLAB_TRACING |
| boolean_t metaslab_trace_enabled = B_TRUE; |
| #endif |
| |
| /* |
| * Maximum entries that the metaslab allocation tracing facility will keep |
| * in a given list when running in non-debug mode. We limit the number |
| * of entries in non-debug mode to prevent us from using up too much memory. |
| * The limit should be sufficiently large that we don't expect any allocation |
| * to every exceed this value. In debug mode, the system will panic if this |
| * limit is ever reached allowing for further investigation. |
| */ |
| #ifdef _METASLAB_TRACING |
| uint64_t metaslab_trace_max_entries = 5000; |
| #endif |
| |
| /* |
| * Maximum number of metaslabs per group that can be disabled |
| * simultaneously. |
| */ |
| int max_disabled_ms = 3; |
| |
| static uint64_t metaslab_weight(metaslab_t *); |
| static void metaslab_set_fragmentation(metaslab_t *); |
| static void metaslab_free_impl(vdev_t *, uint64_t, uint64_t, boolean_t); |
| static void metaslab_check_free_impl(vdev_t *, uint64_t, uint64_t); |
| |
| static void metaslab_passivate(metaslab_t *msp, uint64_t weight); |
| static uint64_t metaslab_weight_from_range_tree(metaslab_t *msp); |
| #ifdef _METASLAB_TRACING |
| kmem_cache_t *metaslab_alloc_trace_cache; |
| #endif |
| |
| /* |
| * ========================================================================== |
| * Metaslab classes |
| * ========================================================================== |
| */ |
| metaslab_class_t * |
| metaslab_class_create(spa_t *spa, metaslab_ops_t *ops) |
| { |
| metaslab_class_t *mc; |
| |
| mc = kmem_zalloc(sizeof (metaslab_class_t), KM_SLEEP); |
| |
| mc->mc_spa = spa; |
| mc->mc_rotor = NULL; |
| mc->mc_ops = ops; |
| mutex_init(&mc->mc_lock, NULL, MUTEX_DEFAULT, NULL); |
| mc->mc_alloc_slots = kmem_zalloc(spa->spa_alloc_count * |
| sizeof (zfs_refcount_t), KM_SLEEP); |
| mc->mc_alloc_max_slots = kmem_zalloc(spa->spa_alloc_count * |
| sizeof (uint64_t), KM_SLEEP); |
| for (int i = 0; i < spa->spa_alloc_count; i++) |
| zfs_refcount_create_tracked(&mc->mc_alloc_slots[i]); |
| |
| return (mc); |
| } |
| |
| void |
| metaslab_class_destroy(metaslab_class_t *mc) |
| { |
| ASSERT(mc->mc_rotor == NULL); |
| ASSERT(mc->mc_alloc == 0); |
| ASSERT(mc->mc_deferred == 0); |
| ASSERT(mc->mc_space == 0); |
| ASSERT(mc->mc_dspace == 0); |
| |
| for (int i = 0; i < mc->mc_spa->spa_alloc_count; i++) |
| zfs_refcount_destroy(&mc->mc_alloc_slots[i]); |
| kmem_free(mc->mc_alloc_slots, mc->mc_spa->spa_alloc_count * |
| sizeof (zfs_refcount_t)); |
| kmem_free(mc->mc_alloc_max_slots, mc->mc_spa->spa_alloc_count * |
| sizeof (uint64_t)); |
| mutex_destroy(&mc->mc_lock); |
| kmem_free(mc, sizeof (metaslab_class_t)); |
| } |
| |
| int |
| metaslab_class_validate(metaslab_class_t *mc) |
| { |
| metaslab_group_t *mg; |
| vdev_t *vd; |
| |
| /* |
| * Must hold one of the spa_config locks. |
| */ |
| ASSERT(spa_config_held(mc->mc_spa, SCL_ALL, RW_READER) || |
| spa_config_held(mc->mc_spa, SCL_ALL, RW_WRITER)); |
| |
| if ((mg = mc->mc_rotor) == NULL) |
| return (0); |
| |
| do { |
| vd = mg->mg_vd; |
| ASSERT(vd->vdev_mg != NULL); |
| ASSERT3P(vd->vdev_top, ==, vd); |
| ASSERT3P(mg->mg_class, ==, mc); |
| ASSERT3P(vd->vdev_ops, !=, &vdev_hole_ops); |
| } while ((mg = mg->mg_next) != mc->mc_rotor); |
| |
| return (0); |
| } |
| |
| static void |
| metaslab_class_space_update(metaslab_class_t *mc, int64_t alloc_delta, |
| int64_t defer_delta, int64_t space_delta, int64_t dspace_delta) |
| { |
| atomic_add_64(&mc->mc_alloc, alloc_delta); |
| atomic_add_64(&mc->mc_deferred, defer_delta); |
| atomic_add_64(&mc->mc_space, space_delta); |
| atomic_add_64(&mc->mc_dspace, dspace_delta); |
| } |
| |
| uint64_t |
| metaslab_class_get_alloc(metaslab_class_t *mc) |
| { |
| return (mc->mc_alloc); |
| } |
| |
| uint64_t |
| metaslab_class_get_deferred(metaslab_class_t *mc) |
| { |
| return (mc->mc_deferred); |
| } |
| |
| uint64_t |
| metaslab_class_get_space(metaslab_class_t *mc) |
| { |
| return (mc->mc_space); |
| } |
| |
| uint64_t |
| metaslab_class_get_dspace(metaslab_class_t *mc) |
| { |
| return (spa_deflate(mc->mc_spa) ? mc->mc_dspace : mc->mc_space); |
| } |
| |
| void |
| metaslab_class_histogram_verify(metaslab_class_t *mc) |
| { |
| spa_t *spa = mc->mc_spa; |
| vdev_t *rvd = spa->spa_root_vdev; |
| uint64_t *mc_hist; |
| int i; |
| |
| if ((zfs_flags & ZFS_DEBUG_HISTOGRAM_VERIFY) == 0) |
| return; |
| |
| mc_hist = kmem_zalloc(sizeof (uint64_t) * RANGE_TREE_HISTOGRAM_SIZE, |
| KM_SLEEP); |
| |
| for (int c = 0; c < rvd->vdev_children; c++) { |
| vdev_t *tvd = rvd->vdev_child[c]; |
| metaslab_group_t *mg = tvd->vdev_mg; |
| |
| /* |
| * Skip any holes, uninitialized top-levels, or |
| * vdevs that are not in this metalab class. |
| */ |
| if (!vdev_is_concrete(tvd) || tvd->vdev_ms_shift == 0 || |
| mg->mg_class != mc) { |
| continue; |
| } |
| |
| for (i = 0; i < RANGE_TREE_HISTOGRAM_SIZE; i++) |
| mc_hist[i] += mg->mg_histogram[i]; |
| } |
| |
| for (i = 0; i < RANGE_TREE_HISTOGRAM_SIZE; i++) |
| VERIFY3U(mc_hist[i], ==, mc->mc_histogram[i]); |
| |
| kmem_free(mc_hist, sizeof (uint64_t) * RANGE_TREE_HISTOGRAM_SIZE); |
| } |
| |
| /* |
| * Calculate the metaslab class's fragmentation metric. The metric |
| * is weighted based on the space contribution of each metaslab group. |
| * The return value will be a number between 0 and 100 (inclusive), or |
| * ZFS_FRAG_INVALID if the metric has not been set. See comment above the |
| * zfs_frag_table for more information about the metric. |
| */ |
| uint64_t |
| metaslab_class_fragmentation(metaslab_class_t *mc) |
| { |
| vdev_t *rvd = mc->mc_spa->spa_root_vdev; |
| uint64_t fragmentation = 0; |
| |
| spa_config_enter(mc->mc_spa, SCL_VDEV, FTAG, RW_READER); |
| |
| for (int c = 0; c < rvd->vdev_children; c++) { |
| vdev_t *tvd = rvd->vdev_child[c]; |
| metaslab_group_t *mg = tvd->vdev_mg; |
| |
| /* |
| * Skip any holes, uninitialized top-levels, |
| * or vdevs that are not in this metalab class. |
| */ |
| if (!vdev_is_concrete(tvd) || tvd->vdev_ms_shift == 0 || |
| mg->mg_class != mc) { |
| continue; |
| } |
| |
| /* |
| * If a metaslab group does not contain a fragmentation |
| * metric then just bail out. |
| */ |
| if (mg->mg_fragmentation == ZFS_FRAG_INVALID) { |
| spa_config_exit(mc->mc_spa, SCL_VDEV, FTAG); |
| return (ZFS_FRAG_INVALID); |
| } |
| |
| /* |
| * Determine how much this metaslab_group is contributing |
| * to the overall pool fragmentation metric. |
| */ |
| fragmentation += mg->mg_fragmentation * |
| metaslab_group_get_space(mg); |
| } |
| fragmentation /= metaslab_class_get_space(mc); |
| |
| ASSERT3U(fragmentation, <=, 100); |
| spa_config_exit(mc->mc_spa, SCL_VDEV, FTAG); |
| return (fragmentation); |
| } |
| |
| /* |
| * Calculate the amount of expandable space that is available in |
| * this metaslab class. If a device is expanded then its expandable |
| * space will be the amount of allocatable space that is currently not |
| * part of this metaslab class. |
| */ |
| uint64_t |
| metaslab_class_expandable_space(metaslab_class_t *mc) |
| { |
| vdev_t *rvd = mc->mc_spa->spa_root_vdev; |
| uint64_t space = 0; |
| |
| spa_config_enter(mc->mc_spa, SCL_VDEV, FTAG, RW_READER); |
| for (int c = 0; c < rvd->vdev_children; c++) { |
| vdev_t *tvd = rvd->vdev_child[c]; |
| metaslab_group_t *mg = tvd->vdev_mg; |
| |
| if (!vdev_is_concrete(tvd) || tvd->vdev_ms_shift == 0 || |
| mg->mg_class != mc) { |
| continue; |
| } |
| |
| /* |
| * Calculate if we have enough space to add additional |
| * metaslabs. We report the expandable space in terms |
| * of the metaslab size since that's the unit of expansion. |
| */ |
| space += P2ALIGN(tvd->vdev_max_asize - tvd->vdev_asize, |
| 1ULL << tvd->vdev_ms_shift); |
| } |
| spa_config_exit(mc->mc_spa, SCL_VDEV, FTAG); |
| return (space); |
| } |
| |
| static int |
| metaslab_compare(const void *x1, const void *x2) |
| { |
| const metaslab_t *m1 = (const metaslab_t *)x1; |
| const metaslab_t *m2 = (const metaslab_t *)x2; |
| |
| int sort1 = 0; |
| int sort2 = 0; |
| if (m1->ms_allocator != -1 && m1->ms_primary) |
| sort1 = 1; |
| else if (m1->ms_allocator != -1 && !m1->ms_primary) |
| sort1 = 2; |
| if (m2->ms_allocator != -1 && m2->ms_primary) |
| sort2 = 1; |
| else if (m2->ms_allocator != -1 && !m2->ms_primary) |
| sort2 = 2; |
| |
| /* |
| * Sort inactive metaslabs first, then primaries, then secondaries. When |
| * selecting a metaslab to allocate from, an allocator first tries its |
| * primary, then secondary active metaslab. If it doesn't have active |
| * metaslabs, or can't allocate from them, it searches for an inactive |
| * metaslab to activate. If it can't find a suitable one, it will steal |
| * a primary or secondary metaslab from another allocator. |
| */ |
| if (sort1 < sort2) |
| return (-1); |
| if (sort1 > sort2) |
| return (1); |
| |
| int cmp = AVL_CMP(m2->ms_weight, m1->ms_weight); |
| if (likely(cmp)) |
| return (cmp); |
| |
| IMPLY(AVL_CMP(m1->ms_start, m2->ms_start) == 0, m1 == m2); |
| |
| return (AVL_CMP(m1->ms_start, m2->ms_start)); |
| } |
| |
| uint64_t |
| metaslab_allocated_space(metaslab_t *msp) |
| { |
| return (msp->ms_allocated_space); |
| } |
| |
| /* |
| * Verify that the space accounting on disk matches the in-core range_trees. |
| */ |
| static void |
| metaslab_verify_space(metaslab_t *msp, uint64_t txg) |
| { |
| spa_t *spa = msp->ms_group->mg_vd->vdev_spa; |
| uint64_t allocating = 0; |
| uint64_t sm_free_space, msp_free_space; |
| |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| ASSERT(!msp->ms_condensing); |
| |
| if ((zfs_flags & ZFS_DEBUG_METASLAB_VERIFY) == 0) |
| return; |
| |
| /* |
| * We can only verify the metaslab space when we're called |
| * from syncing context with a loaded metaslab that has an |
| * allocated space map. Calling this in non-syncing context |
| * does not provide a consistent view of the metaslab since |
| * we're performing allocations in the future. |
| */ |
| if (txg != spa_syncing_txg(spa) || msp->ms_sm == NULL || |
| !msp->ms_loaded) |
| return; |
| |
| /* |
| * Even though the smp_alloc field can get negative (e.g. |
| * see vdev_checkpoint_sm), that should never be the case |
| * when it come's to a metaslab's space map. |
| */ |
| ASSERT3S(space_map_allocated(msp->ms_sm), >=, 0); |
| |
| sm_free_space = msp->ms_size - metaslab_allocated_space(msp); |
| |
| /* |
| * Account for future allocations since we would have |
| * already deducted that space from the ms_allocatable. |
| */ |
| for (int t = 0; t < TXG_CONCURRENT_STATES; t++) { |
| allocating += |
| range_tree_space(msp->ms_allocating[(txg + t) & TXG_MASK]); |
| } |
| |
| ASSERT3U(msp->ms_deferspace, ==, |
| range_tree_space(msp->ms_defer[0]) + |
| range_tree_space(msp->ms_defer[1])); |
| |
| msp_free_space = range_tree_space(msp->ms_allocatable) + allocating + |
| msp->ms_deferspace + range_tree_space(msp->ms_freed); |
| |
| VERIFY3U(sm_free_space, ==, msp_free_space); |
| } |
| |
| /* |
| * ========================================================================== |
| * Metaslab groups |
| * ========================================================================== |
| */ |
| /* |
| * Update the allocatable flag and the metaslab group's capacity. |
| * The allocatable flag is set to true if the capacity is below |
| * the zfs_mg_noalloc_threshold or has a fragmentation value that is |
| * greater than zfs_mg_fragmentation_threshold. If a metaslab group |
| * transitions from allocatable to non-allocatable or vice versa then the |
| * metaslab group's class is updated to reflect the transition. |
| */ |
| static void |
| metaslab_group_alloc_update(metaslab_group_t *mg) |
| { |
| vdev_t *vd = mg->mg_vd; |
| metaslab_class_t *mc = mg->mg_class; |
| vdev_stat_t *vs = &vd->vdev_stat; |
| boolean_t was_allocatable; |
| boolean_t was_initialized; |
| |
| ASSERT(vd == vd->vdev_top); |
| ASSERT3U(spa_config_held(mc->mc_spa, SCL_ALLOC, RW_READER), ==, |
| SCL_ALLOC); |
| |
| mutex_enter(&mg->mg_lock); |
| was_allocatable = mg->mg_allocatable; |
| was_initialized = mg->mg_initialized; |
| |
| mg->mg_free_capacity = ((vs->vs_space - vs->vs_alloc) * 100) / |
| (vs->vs_space + 1); |
| |
| mutex_enter(&mc->mc_lock); |
| |
| /* |
| * If the metaslab group was just added then it won't |
| * have any space until we finish syncing out this txg. |
| * At that point we will consider it initialized and available |
| * for allocations. We also don't consider non-activated |
| * metaslab groups (e.g. vdevs that are in the middle of being removed) |
| * to be initialized, because they can't be used for allocation. |
| */ |
| mg->mg_initialized = metaslab_group_initialized(mg); |
| if (!was_initialized && mg->mg_initialized) { |
| mc->mc_groups++; |
| } else if (was_initialized && !mg->mg_initialized) { |
| ASSERT3U(mc->mc_groups, >, 0); |
| mc->mc_groups--; |
| } |
| if (mg->mg_initialized) |
| mg->mg_no_free_space = B_FALSE; |
| |
| /* |
| * A metaslab group is considered allocatable if it has plenty |
| * of free space or is not heavily fragmented. We only take |
| * fragmentation into account if the metaslab group has a valid |
| * fragmentation metric (i.e. a value between 0 and 100). |
| */ |
| mg->mg_allocatable = (mg->mg_activation_count > 0 && |
| mg->mg_free_capacity > zfs_mg_noalloc_threshold && |
| (mg->mg_fragmentation == ZFS_FRAG_INVALID || |
| mg->mg_fragmentation <= zfs_mg_fragmentation_threshold)); |
| |
| /* |
| * The mc_alloc_groups maintains a count of the number of |
| * groups in this metaslab class that are still above the |
| * zfs_mg_noalloc_threshold. This is used by the allocating |
| * threads to determine if they should avoid allocations to |
| * a given group. The allocator will avoid allocations to a group |
| * if that group has reached or is below the zfs_mg_noalloc_threshold |
| * and there are still other groups that are above the threshold. |
| * When a group transitions from allocatable to non-allocatable or |
| * vice versa we update the metaslab class to reflect that change. |
| * When the mc_alloc_groups value drops to 0 that means that all |
| * groups have reached the zfs_mg_noalloc_threshold making all groups |
| * eligible for allocations. This effectively means that all devices |
| * are balanced again. |
| */ |
| if (was_allocatable && !mg->mg_allocatable) |
| mc->mc_alloc_groups--; |
| else if (!was_allocatable && mg->mg_allocatable) |
| mc->mc_alloc_groups++; |
| mutex_exit(&mc->mc_lock); |
| |
| mutex_exit(&mg->mg_lock); |
| } |
| |
| metaslab_group_t * |
| metaslab_group_create(metaslab_class_t *mc, vdev_t *vd, int allocators) |
| { |
| metaslab_group_t *mg; |
| |
| mg = kmem_zalloc(sizeof (metaslab_group_t), KM_SLEEP); |
| mutex_init(&mg->mg_lock, NULL, MUTEX_DEFAULT, NULL); |
| mutex_init(&mg->mg_ms_disabled_lock, NULL, MUTEX_DEFAULT, NULL); |
| cv_init(&mg->mg_ms_disabled_cv, NULL, CV_DEFAULT, NULL); |
| mg->mg_primaries = kmem_zalloc(allocators * sizeof (metaslab_t *), |
| KM_SLEEP); |
| mg->mg_secondaries = kmem_zalloc(allocators * sizeof (metaslab_t *), |
| KM_SLEEP); |
| avl_create(&mg->mg_metaslab_tree, metaslab_compare, |
| sizeof (metaslab_t), offsetof(struct metaslab, ms_group_node)); |
| mg->mg_vd = vd; |
| mg->mg_class = mc; |
| mg->mg_activation_count = 0; |
| mg->mg_initialized = B_FALSE; |
| mg->mg_no_free_space = B_TRUE; |
| mg->mg_allocators = allocators; |
| |
| mg->mg_alloc_queue_depth = kmem_zalloc(allocators * |
| sizeof (zfs_refcount_t), KM_SLEEP); |
| mg->mg_cur_max_alloc_queue_depth = kmem_zalloc(allocators * |
| sizeof (uint64_t), KM_SLEEP); |
| for (int i = 0; i < allocators; i++) { |
| zfs_refcount_create_tracked(&mg->mg_alloc_queue_depth[i]); |
| mg->mg_cur_max_alloc_queue_depth[i] = 0; |
| } |
| |
| mg->mg_taskq = taskq_create("metaslab_group_taskq", metaslab_load_pct, |
| maxclsyspri, 10, INT_MAX, TASKQ_THREADS_CPU_PCT | TASKQ_DYNAMIC); |
| |
| return (mg); |
| } |
| |
| void |
| metaslab_group_destroy(metaslab_group_t *mg) |
| { |
| ASSERT(mg->mg_prev == NULL); |
| ASSERT(mg->mg_next == NULL); |
| /* |
| * We may have gone below zero with the activation count |
| * either because we never activated in the first place or |
| * because we're done, and possibly removing the vdev. |
| */ |
| ASSERT(mg->mg_activation_count <= 0); |
| |
| taskq_destroy(mg->mg_taskq); |
| avl_destroy(&mg->mg_metaslab_tree); |
| kmem_free(mg->mg_primaries, mg->mg_allocators * sizeof (metaslab_t *)); |
| kmem_free(mg->mg_secondaries, mg->mg_allocators * |
| sizeof (metaslab_t *)); |
| mutex_destroy(&mg->mg_lock); |
| mutex_destroy(&mg->mg_ms_disabled_lock); |
| cv_destroy(&mg->mg_ms_disabled_cv); |
| |
| for (int i = 0; i < mg->mg_allocators; i++) { |
| zfs_refcount_destroy(&mg->mg_alloc_queue_depth[i]); |
| mg->mg_cur_max_alloc_queue_depth[i] = 0; |
| } |
| kmem_free(mg->mg_alloc_queue_depth, mg->mg_allocators * |
| sizeof (zfs_refcount_t)); |
| kmem_free(mg->mg_cur_max_alloc_queue_depth, mg->mg_allocators * |
| sizeof (uint64_t)); |
| |
| kmem_free(mg, sizeof (metaslab_group_t)); |
| } |
| |
| void |
| metaslab_group_activate(metaslab_group_t *mg) |
| { |
| metaslab_class_t *mc = mg->mg_class; |
| metaslab_group_t *mgprev, *mgnext; |
| |
| ASSERT3U(spa_config_held(mc->mc_spa, SCL_ALLOC, RW_WRITER), !=, 0); |
| |
| ASSERT(mc->mc_rotor != mg); |
| ASSERT(mg->mg_prev == NULL); |
| ASSERT(mg->mg_next == NULL); |
| ASSERT(mg->mg_activation_count <= 0); |
| |
| if (++mg->mg_activation_count <= 0) |
| return; |
| |
| mg->mg_aliquot = metaslab_aliquot * MAX(1, mg->mg_vd->vdev_children); |
| metaslab_group_alloc_update(mg); |
| |
| if ((mgprev = mc->mc_rotor) == NULL) { |
| mg->mg_prev = mg; |
| mg->mg_next = mg; |
| } else { |
| mgnext = mgprev->mg_next; |
| mg->mg_prev = mgprev; |
| mg->mg_next = mgnext; |
| mgprev->mg_next = mg; |
| mgnext->mg_prev = mg; |
| } |
| mc->mc_rotor = mg; |
| } |
| |
| /* |
| * Passivate a metaslab group and remove it from the allocation rotor. |
| * Callers must hold both the SCL_ALLOC and SCL_ZIO lock prior to passivating |
| * a metaslab group. This function will momentarily drop spa_config_locks |
| * that are lower than the SCL_ALLOC lock (see comment below). |
| */ |
| void |
| metaslab_group_passivate(metaslab_group_t *mg) |
| { |
| metaslab_class_t *mc = mg->mg_class; |
| spa_t *spa = mc->mc_spa; |
| metaslab_group_t *mgprev, *mgnext; |
| int locks = spa_config_held(spa, SCL_ALL, RW_WRITER); |
| |
| ASSERT3U(spa_config_held(spa, SCL_ALLOC | SCL_ZIO, RW_WRITER), ==, |
| (SCL_ALLOC | SCL_ZIO)); |
| |
| if (--mg->mg_activation_count != 0) { |
| ASSERT(mc->mc_rotor != mg); |
| ASSERT(mg->mg_prev == NULL); |
| ASSERT(mg->mg_next == NULL); |
| ASSERT(mg->mg_activation_count < 0); |
| return; |
| } |
| |
| /* |
| * The spa_config_lock is an array of rwlocks, ordered as |
| * follows (from highest to lowest): |
| * SCL_CONFIG > SCL_STATE > SCL_L2ARC > SCL_ALLOC > |
| * SCL_ZIO > SCL_FREE > SCL_VDEV |
| * (For more information about the spa_config_lock see spa_misc.c) |
| * The higher the lock, the broader its coverage. When we passivate |
| * a metaslab group, we must hold both the SCL_ALLOC and the SCL_ZIO |
| * config locks. However, the metaslab group's taskq might be trying |
| * to preload metaslabs so we must drop the SCL_ZIO lock and any |
| * lower locks to allow the I/O to complete. At a minimum, |
| * we continue to hold the SCL_ALLOC lock, which prevents any future |
| * allocations from taking place and any changes to the vdev tree. |
| */ |
| spa_config_exit(spa, locks & ~(SCL_ZIO - 1), spa); |
| taskq_wait_outstanding(mg->mg_taskq, 0); |
| spa_config_enter(spa, locks & ~(SCL_ZIO - 1), spa, RW_WRITER); |
| metaslab_group_alloc_update(mg); |
| for (int i = 0; i < mg->mg_allocators; i++) { |
| metaslab_t *msp = mg->mg_primaries[i]; |
| if (msp != NULL) { |
| mutex_enter(&msp->ms_lock); |
| metaslab_passivate(msp, |
| metaslab_weight_from_range_tree(msp)); |
| mutex_exit(&msp->ms_lock); |
| } |
| msp = mg->mg_secondaries[i]; |
| if (msp != NULL) { |
| mutex_enter(&msp->ms_lock); |
| metaslab_passivate(msp, |
| metaslab_weight_from_range_tree(msp)); |
| mutex_exit(&msp->ms_lock); |
| } |
| } |
| |
| mgprev = mg->mg_prev; |
| mgnext = mg->mg_next; |
| |
| if (mg == mgnext) { |
| mc->mc_rotor = NULL; |
| } else { |
| mc->mc_rotor = mgnext; |
| mgprev->mg_next = mgnext; |
| mgnext->mg_prev = mgprev; |
| } |
| |
| mg->mg_prev = NULL; |
| mg->mg_next = NULL; |
| } |
| |
| boolean_t |
| metaslab_group_initialized(metaslab_group_t *mg) |
| { |
| vdev_t *vd = mg->mg_vd; |
| vdev_stat_t *vs = &vd->vdev_stat; |
| |
| return (vs->vs_space != 0 && mg->mg_activation_count > 0); |
| } |
| |
| uint64_t |
| metaslab_group_get_space(metaslab_group_t *mg) |
| { |
| return ((1ULL << mg->mg_vd->vdev_ms_shift) * mg->mg_vd->vdev_ms_count); |
| } |
| |
| void |
| metaslab_group_histogram_verify(metaslab_group_t *mg) |
| { |
| uint64_t *mg_hist; |
| vdev_t *vd = mg->mg_vd; |
| uint64_t ashift = vd->vdev_ashift; |
| int i; |
| |
| if ((zfs_flags & ZFS_DEBUG_HISTOGRAM_VERIFY) == 0) |
| return; |
| |
| mg_hist = kmem_zalloc(sizeof (uint64_t) * RANGE_TREE_HISTOGRAM_SIZE, |
| KM_SLEEP); |
| |
| ASSERT3U(RANGE_TREE_HISTOGRAM_SIZE, >=, |
| SPACE_MAP_HISTOGRAM_SIZE + ashift); |
| |
| for (int m = 0; m < vd->vdev_ms_count; m++) { |
| metaslab_t *msp = vd->vdev_ms[m]; |
| ASSERT(msp != NULL); |
| |
| /* skip if not active or not a member */ |
| if (msp->ms_sm == NULL || msp->ms_group != mg) |
| continue; |
| |
| for (i = 0; i < SPACE_MAP_HISTOGRAM_SIZE; i++) |
| mg_hist[i + ashift] += |
| msp->ms_sm->sm_phys->smp_histogram[i]; |
| } |
| |
| for (i = 0; i < RANGE_TREE_HISTOGRAM_SIZE; i ++) |
| VERIFY3U(mg_hist[i], ==, mg->mg_histogram[i]); |
| |
| kmem_free(mg_hist, sizeof (uint64_t) * RANGE_TREE_HISTOGRAM_SIZE); |
| } |
| |
| static void |
| metaslab_group_histogram_add(metaslab_group_t *mg, metaslab_t *msp) |
| { |
| metaslab_class_t *mc = mg->mg_class; |
| uint64_t ashift = mg->mg_vd->vdev_ashift; |
| |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| if (msp->ms_sm == NULL) |
| return; |
| |
| mutex_enter(&mg->mg_lock); |
| for (int i = 0; i < SPACE_MAP_HISTOGRAM_SIZE; i++) { |
| mg->mg_histogram[i + ashift] += |
| msp->ms_sm->sm_phys->smp_histogram[i]; |
| mc->mc_histogram[i + ashift] += |
| msp->ms_sm->sm_phys->smp_histogram[i]; |
| } |
| mutex_exit(&mg->mg_lock); |
| } |
| |
| void |
| metaslab_group_histogram_remove(metaslab_group_t *mg, metaslab_t *msp) |
| { |
| metaslab_class_t *mc = mg->mg_class; |
| uint64_t ashift = mg->mg_vd->vdev_ashift; |
| |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| if (msp->ms_sm == NULL) |
| return; |
| |
| mutex_enter(&mg->mg_lock); |
| for (int i = 0; i < SPACE_MAP_HISTOGRAM_SIZE; i++) { |
| ASSERT3U(mg->mg_histogram[i + ashift], >=, |
| msp->ms_sm->sm_phys->smp_histogram[i]); |
| ASSERT3U(mc->mc_histogram[i + ashift], >=, |
| msp->ms_sm->sm_phys->smp_histogram[i]); |
| |
| mg->mg_histogram[i + ashift] -= |
| msp->ms_sm->sm_phys->smp_histogram[i]; |
| mc->mc_histogram[i + ashift] -= |
| msp->ms_sm->sm_phys->smp_histogram[i]; |
| } |
| mutex_exit(&mg->mg_lock); |
| } |
| |
| static void |
| metaslab_group_add(metaslab_group_t *mg, metaslab_t *msp) |
| { |
| ASSERT(msp->ms_group == NULL); |
| mutex_enter(&mg->mg_lock); |
| msp->ms_group = mg; |
| msp->ms_weight = 0; |
| avl_add(&mg->mg_metaslab_tree, msp); |
| mutex_exit(&mg->mg_lock); |
| |
| mutex_enter(&msp->ms_lock); |
| metaslab_group_histogram_add(mg, msp); |
| mutex_exit(&msp->ms_lock); |
| } |
| |
| static void |
| metaslab_group_remove(metaslab_group_t *mg, metaslab_t *msp) |
| { |
| mutex_enter(&msp->ms_lock); |
| metaslab_group_histogram_remove(mg, msp); |
| mutex_exit(&msp->ms_lock); |
| |
| mutex_enter(&mg->mg_lock); |
| ASSERT(msp->ms_group == mg); |
| avl_remove(&mg->mg_metaslab_tree, msp); |
| msp->ms_group = NULL; |
| mutex_exit(&mg->mg_lock); |
| } |
| |
| static void |
| metaslab_group_sort_impl(metaslab_group_t *mg, metaslab_t *msp, uint64_t weight) |
| { |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| ASSERT(MUTEX_HELD(&mg->mg_lock)); |
| ASSERT(msp->ms_group == mg); |
| |
| avl_remove(&mg->mg_metaslab_tree, msp); |
| msp->ms_weight = weight; |
| avl_add(&mg->mg_metaslab_tree, msp); |
| |
| } |
| |
| static void |
| metaslab_group_sort(metaslab_group_t *mg, metaslab_t *msp, uint64_t weight) |
| { |
| /* |
| * Although in principle the weight can be any value, in |
| * practice we do not use values in the range [1, 511]. |
| */ |
| ASSERT(weight >= SPA_MINBLOCKSIZE || weight == 0); |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| |
| mutex_enter(&mg->mg_lock); |
| metaslab_group_sort_impl(mg, msp, weight); |
| mutex_exit(&mg->mg_lock); |
| } |
| |
| /* |
| * Calculate the fragmentation for a given metaslab group. We can use |
| * a simple average here since all metaslabs within the group must have |
| * the same size. The return value will be a value between 0 and 100 |
| * (inclusive), or ZFS_FRAG_INVALID if less than half of the metaslab in this |
| * group have a fragmentation metric. |
| */ |
| uint64_t |
| metaslab_group_fragmentation(metaslab_group_t *mg) |
| { |
| vdev_t *vd = mg->mg_vd; |
| uint64_t fragmentation = 0; |
| uint64_t valid_ms = 0; |
| |
| for (int m = 0; m < vd->vdev_ms_count; m++) { |
| metaslab_t *msp = vd->vdev_ms[m]; |
| |
| if (msp->ms_fragmentation == ZFS_FRAG_INVALID) |
| continue; |
| if (msp->ms_group != mg) |
| continue; |
| |
| valid_ms++; |
| fragmentation += msp->ms_fragmentation; |
| } |
| |
| if (valid_ms <= mg->mg_vd->vdev_ms_count / 2) |
| return (ZFS_FRAG_INVALID); |
| |
| fragmentation /= valid_ms; |
| ASSERT3U(fragmentation, <=, 100); |
| return (fragmentation); |
| } |
| |
| /* |
| * Determine if a given metaslab group should skip allocations. A metaslab |
| * group should avoid allocations if its free capacity is less than the |
| * zfs_mg_noalloc_threshold or its fragmentation metric is greater than |
| * zfs_mg_fragmentation_threshold and there is at least one metaslab group |
| * that can still handle allocations. If the allocation throttle is enabled |
| * then we skip allocations to devices that have reached their maximum |
| * allocation queue depth unless the selected metaslab group is the only |
| * eligible group remaining. |
| */ |
| static boolean_t |
| metaslab_group_allocatable(metaslab_group_t *mg, metaslab_group_t *rotor, |
| uint64_t psize, int allocator, int d) |
| { |
| spa_t *spa = mg->mg_vd->vdev_spa; |
| metaslab_class_t *mc = mg->mg_class; |
| |
| /* |
| * We can only consider skipping this metaslab group if it's |
| * in the normal metaslab class and there are other metaslab |
| * groups to select from. Otherwise, we always consider it eligible |
| * for allocations. |
| */ |
| if ((mc != spa_normal_class(spa) && |
| mc != spa_special_class(spa) && |
| mc != spa_dedup_class(spa)) || |
| mc->mc_groups <= 1) |
| return (B_TRUE); |
| |
| /* |
| * If the metaslab group's mg_allocatable flag is set (see comments |
| * in metaslab_group_alloc_update() for more information) and |
| * the allocation throttle is disabled then allow allocations to this |
| * device. However, if the allocation throttle is enabled then |
| * check if we have reached our allocation limit (mg_alloc_queue_depth) |
| * to determine if we should allow allocations to this metaslab group. |
| * If all metaslab groups are no longer considered allocatable |
| * (mc_alloc_groups == 0) or we're trying to allocate the smallest |
| * gang block size then we allow allocations on this metaslab group |
| * regardless of the mg_allocatable or throttle settings. |
| */ |
| if (mg->mg_allocatable) { |
| metaslab_group_t *mgp; |
| int64_t qdepth; |
| uint64_t qmax = mg->mg_cur_max_alloc_queue_depth[allocator]; |
| |
| if (!mc->mc_alloc_throttle_enabled) |
| return (B_TRUE); |
| |
| /* |
| * If this metaslab group does not have any free space, then |
| * there is no point in looking further. |
| */ |
| if (mg->mg_no_free_space) |
| return (B_FALSE); |
| |
| /* |
| * Relax allocation throttling for ditto blocks. Due to |
| * random imbalances in allocation it tends to push copies |
| * to one vdev, that looks a bit better at the moment. |
| */ |
| qmax = qmax * (4 + d) / 4; |
| |
| qdepth = zfs_refcount_count( |
| &mg->mg_alloc_queue_depth[allocator]); |
| |
| /* |
| * If this metaslab group is below its qmax or it's |
| * the only allocatable metasable group, then attempt |
| * to allocate from it. |
| */ |
| if (qdepth < qmax || mc->mc_alloc_groups == 1) |
| return (B_TRUE); |
| ASSERT3U(mc->mc_alloc_groups, >, 1); |
| |
| /* |
| * Since this metaslab group is at or over its qmax, we |
| * need to determine if there are metaslab groups after this |
| * one that might be able to handle this allocation. This is |
| * racy since we can't hold the locks for all metaslab |
| * groups at the same time when we make this check. |
| */ |
| for (mgp = mg->mg_next; mgp != rotor; mgp = mgp->mg_next) { |
| qmax = mgp->mg_cur_max_alloc_queue_depth[allocator]; |
| qmax = qmax * (4 + d) / 4; |
| qdepth = zfs_refcount_count( |
| &mgp->mg_alloc_queue_depth[allocator]); |
| |
| /* |
| * If there is another metaslab group that |
| * might be able to handle the allocation, then |
| * we return false so that we skip this group. |
| */ |
| if (qdepth < qmax && !mgp->mg_no_free_space) |
| return (B_FALSE); |
| } |
| |
| /* |
| * We didn't find another group to handle the allocation |
| * so we can't skip this metaslab group even though |
| * we are at or over our qmax. |
| */ |
| return (B_TRUE); |
| |
| } else if (mc->mc_alloc_groups == 0 || psize == SPA_MINBLOCKSIZE) { |
| return (B_TRUE); |
| } |
| return (B_FALSE); |
| } |
| |
| /* |
| * ========================================================================== |
| * Range tree callbacks |
| * ========================================================================== |
| */ |
| |
| /* |
| * Comparison function for the private size-ordered tree. Tree is sorted |
| * by size, larger sizes at the end of the tree. |
| */ |
| static int |
| metaslab_rangesize_compare(const void *x1, const void *x2) |
| { |
| const range_seg_t *r1 = x1; |
| const range_seg_t *r2 = x2; |
| uint64_t rs_size1 = r1->rs_end - r1->rs_start; |
| uint64_t rs_size2 = r2->rs_end - r2->rs_start; |
| |
| int cmp = AVL_CMP(rs_size1, rs_size2); |
| if (likely(cmp)) |
| return (cmp); |
| |
| return (AVL_CMP(r1->rs_start, r2->rs_start)); |
| } |
| |
| /* |
| * ========================================================================== |
| * Common allocator routines |
| * ========================================================================== |
| */ |
| |
| /* |
| * Return the maximum contiguous segment within the metaslab. |
| */ |
| uint64_t |
| metaslab_block_maxsize(metaslab_t *msp) |
| { |
| avl_tree_t *t = &msp->ms_allocatable_by_size; |
| range_seg_t *rs; |
| |
| if (t == NULL || (rs = avl_last(t)) == NULL) |
| return (0ULL); |
| |
| return (rs->rs_end - rs->rs_start); |
| } |
| |
| static range_seg_t * |
| metaslab_block_find(avl_tree_t *t, uint64_t start, uint64_t size) |
| { |
| range_seg_t *rs, rsearch; |
| avl_index_t where; |
| |
| rsearch.rs_start = start; |
| rsearch.rs_end = start + size; |
| |
| rs = avl_find(t, &rsearch, &where); |
| if (rs == NULL) { |
| rs = avl_nearest(t, where, AVL_AFTER); |
| } |
| |
| return (rs); |
| } |
| |
| #if defined(WITH_DF_BLOCK_ALLOCATOR) || \ |
| defined(WITH_CF_BLOCK_ALLOCATOR) |
| /* |
| * This is a helper function that can be used by the allocator to find |
| * a suitable block to allocate. This will search the specified AVL |
| * tree looking for a block that matches the specified criteria. |
| */ |
| static uint64_t |
| metaslab_block_picker(avl_tree_t *t, uint64_t *cursor, uint64_t size, |
| uint64_t max_search) |
| { |
| range_seg_t *rs = metaslab_block_find(t, *cursor, size); |
| uint64_t first_found; |
| |
| if (rs != NULL) |
| first_found = rs->rs_start; |
| |
| while (rs != NULL && rs->rs_start - first_found <= max_search) { |
| uint64_t offset = rs->rs_start; |
| if (offset + size <= rs->rs_end) { |
| *cursor = offset + size; |
| return (offset); |
| } |
| rs = AVL_NEXT(t, rs); |
| } |
| |
| *cursor = 0; |
| return (-1ULL); |
| } |
| #endif /* WITH_DF/CF_BLOCK_ALLOCATOR */ |
| |
| #if defined(WITH_DF_BLOCK_ALLOCATOR) |
| /* |
| * ========================================================================== |
| * Dynamic Fit (df) block allocator |
| * |
| * Search for a free chunk of at least this size, starting from the last |
| * offset (for this alignment of block) looking for up to |
| * metaslab_df_max_search bytes (16MB). If a large enough free chunk is not |
| * found within 16MB, then return a free chunk of exactly the requested size (or |
| * larger). |
| * |
| * If it seems like searching from the last offset will be unproductive, skip |
| * that and just return a free chunk of exactly the requested size (or larger). |
| * This is based on metaslab_df_alloc_threshold and metaslab_df_free_pct. This |
| * mechanism is probably not very useful and may be removed in the future. |
| * |
| * The behavior when not searching can be changed to return the largest free |
| * chunk, instead of a free chunk of exactly the requested size, by setting |
| * metaslab_df_use_largest_segment. |
| * ========================================================================== |
| */ |
| static uint64_t |
| metaslab_df_alloc(metaslab_t *msp, uint64_t size) |
| { |
| /* |
| * Find the largest power of 2 block size that evenly divides the |
| * requested size. This is used to try to allocate blocks with similar |
| * alignment from the same area of the metaslab (i.e. same cursor |
| * bucket) but it does not guarantee that other allocations sizes |
| * may exist in the same region. |
| */ |
| uint64_t align = size & -size; |
| uint64_t *cursor = &msp->ms_lbas[highbit64(align) - 1]; |
| range_tree_t *rt = msp->ms_allocatable; |
| int free_pct = range_tree_space(rt) * 100 / msp->ms_size; |
| uint64_t offset; |
| |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| ASSERT3U(avl_numnodes(&rt->rt_root), ==, |
| avl_numnodes(&msp->ms_allocatable_by_size)); |
| |
| /* |
| * If we're running low on space, find a segment based on size, |
| * rather than iterating based on offset. |
| */ |
| if (metaslab_block_maxsize(msp) < metaslab_df_alloc_threshold || |
| free_pct < metaslab_df_free_pct) { |
| offset = -1; |
| } else { |
| offset = metaslab_block_picker(&rt->rt_root, |
| cursor, size, metaslab_df_max_search); |
| } |
| |
| if (offset == -1) { |
| range_seg_t *rs; |
| if (metaslab_df_use_largest_segment) { |
| /* use largest free segment */ |
| rs = avl_last(&msp->ms_allocatable_by_size); |
| } else { |
| /* use segment of this size, or next largest */ |
| rs = metaslab_block_find(&msp->ms_allocatable_by_size, |
| 0, size); |
| } |
| if (rs != NULL && rs->rs_start + size <= rs->rs_end) { |
| offset = rs->rs_start; |
| *cursor = offset + size; |
| } |
| } |
| |
| return (offset); |
| } |
| |
| static metaslab_ops_t metaslab_df_ops = { |
| metaslab_df_alloc |
| }; |
| |
| metaslab_ops_t *zfs_metaslab_ops = &metaslab_df_ops; |
| #endif /* WITH_DF_BLOCK_ALLOCATOR */ |
| |
| #if defined(WITH_CF_BLOCK_ALLOCATOR) |
| /* |
| * ========================================================================== |
| * Cursor fit block allocator - |
| * Select the largest region in the metaslab, set the cursor to the beginning |
| * of the range and the cursor_end to the end of the range. As allocations |
| * are made advance the cursor. Continue allocating from the cursor until |
| * the range is exhausted and then find a new range. |
| * ========================================================================== |
| */ |
| static uint64_t |
| metaslab_cf_alloc(metaslab_t *msp, uint64_t size) |
| { |
| range_tree_t *rt = msp->ms_allocatable; |
| avl_tree_t *t = &msp->ms_allocatable_by_size; |
| uint64_t *cursor = &msp->ms_lbas[0]; |
| uint64_t *cursor_end = &msp->ms_lbas[1]; |
| uint64_t offset = 0; |
| |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| ASSERT3U(avl_numnodes(t), ==, avl_numnodes(&rt->rt_root)); |
| |
| ASSERT3U(*cursor_end, >=, *cursor); |
| |
| if ((*cursor + size) > *cursor_end) { |
| range_seg_t *rs; |
| |
| rs = avl_last(&msp->ms_allocatable_by_size); |
| if (rs == NULL || (rs->rs_end - rs->rs_start) < size) |
| return (-1ULL); |
| |
| *cursor = rs->rs_start; |
| *cursor_end = rs->rs_end; |
| } |
| |
| offset = *cursor; |
| *cursor += size; |
| |
| return (offset); |
| } |
| |
| static metaslab_ops_t metaslab_cf_ops = { |
| metaslab_cf_alloc |
| }; |
| |
| metaslab_ops_t *zfs_metaslab_ops = &metaslab_cf_ops; |
| #endif /* WITH_CF_BLOCK_ALLOCATOR */ |
| |
| #if defined(WITH_NDF_BLOCK_ALLOCATOR) |
| /* |
| * ========================================================================== |
| * New dynamic fit allocator - |
| * Select a region that is large enough to allocate 2^metaslab_ndf_clump_shift |
| * contiguous blocks. If no region is found then just use the largest segment |
| * that remains. |
| * ========================================================================== |
| */ |
| |
| /* |
| * Determines desired number of contiguous blocks (2^metaslab_ndf_clump_shift) |
| * to request from the allocator. |
| */ |
| uint64_t metaslab_ndf_clump_shift = 4; |
| |
| static uint64_t |
| metaslab_ndf_alloc(metaslab_t *msp, uint64_t size) |
| { |
| avl_tree_t *t = &msp->ms_allocatable->rt_root; |
| avl_index_t where; |
| range_seg_t *rs, rsearch; |
| uint64_t hbit = highbit64(size); |
| uint64_t *cursor = &msp->ms_lbas[hbit - 1]; |
| uint64_t max_size = metaslab_block_maxsize(msp); |
| |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| ASSERT3U(avl_numnodes(t), ==, |
| avl_numnodes(&msp->ms_allocatable_by_size)); |
| |
| if (max_size < size) |
| return (-1ULL); |
| |
| rsearch.rs_start = *cursor; |
| rsearch.rs_end = *cursor + size; |
| |
| rs = avl_find(t, &rsearch, &where); |
| if (rs == NULL || (rs->rs_end - rs->rs_start) < size) { |
| t = &msp->ms_allocatable_by_size; |
| |
| rsearch.rs_start = 0; |
| rsearch.rs_end = MIN(max_size, |
| 1ULL << (hbit + metaslab_ndf_clump_shift)); |
| rs = avl_find(t, &rsearch, &where); |
| if (rs == NULL) |
| rs = avl_nearest(t, where, AVL_AFTER); |
| ASSERT(rs != NULL); |
| } |
| |
| if ((rs->rs_end - rs->rs_start) >= size) { |
| *cursor = rs->rs_start + size; |
| return (rs->rs_start); |
| } |
| return (-1ULL); |
| } |
| |
| static metaslab_ops_t metaslab_ndf_ops = { |
| metaslab_ndf_alloc |
| }; |
| |
| metaslab_ops_t *zfs_metaslab_ops = &metaslab_ndf_ops; |
| #endif /* WITH_NDF_BLOCK_ALLOCATOR */ |
| |
| |
| /* |
| * ========================================================================== |
| * Metaslabs |
| * ========================================================================== |
| */ |
| |
| static void |
| metaslab_aux_histograms_clear(metaslab_t *msp) |
| { |
| /* |
| * Auxiliary histograms are only cleared when resetting them, |
| * which can only happen while the metaslab is loaded. |
| */ |
| ASSERT(msp->ms_loaded); |
| |
| bzero(msp->ms_synchist, sizeof (msp->ms_synchist)); |
| for (int t = 0; t < TXG_DEFER_SIZE; t++) |
| bzero(msp->ms_deferhist[t], sizeof (msp->ms_deferhist[t])); |
| } |
| |
| static void |
| metaslab_aux_histogram_add(uint64_t *histogram, uint64_t shift, |
| range_tree_t *rt) |
| { |
| /* |
| * This is modeled after space_map_histogram_add(), so refer to that |
| * function for implementation details. We want this to work like |
| * the space map histogram, and not the range tree histogram, as we |
| * are essentially constructing a delta that will be later subtracted |
| * from the space map histogram. |
| */ |
| int idx = 0; |
| for (int i = shift; i < RANGE_TREE_HISTOGRAM_SIZE; i++) { |
| ASSERT3U(i, >=, idx + shift); |
| histogram[idx] += rt->rt_histogram[i] << (i - idx - shift); |
| |
| if (idx < SPACE_MAP_HISTOGRAM_SIZE - 1) { |
| ASSERT3U(idx + shift, ==, i); |
| idx++; |
| ASSERT3U(idx, <, SPACE_MAP_HISTOGRAM_SIZE); |
| } |
| } |
| } |
| |
| /* |
| * Called at every sync pass that the metaslab gets synced. |
| * |
| * The reason is that we want our auxiliary histograms to be updated |
| * wherever the metaslab's space map histogram is updated. This way |
| * we stay consistent on which parts of the metaslab space map's |
| * histogram are currently not available for allocations (e.g because |
| * they are in the defer, freed, and freeing trees). |
| */ |
| static void |
| metaslab_aux_histograms_update(metaslab_t *msp) |
| { |
| space_map_t *sm = msp->ms_sm; |
| ASSERT(sm != NULL); |
| |
| /* |
| * This is similar to the metaslab's space map histogram updates |
| * that take place in metaslab_sync(). The only difference is that |
| * we only care about segments that haven't made it into the |
| * ms_allocatable tree yet. |
| */ |
| if (msp->ms_loaded) { |
| metaslab_aux_histograms_clear(msp); |
| |
| metaslab_aux_histogram_add(msp->ms_synchist, |
| sm->sm_shift, msp->ms_freed); |
| |
| for (int t = 0; t < TXG_DEFER_SIZE; t++) { |
| metaslab_aux_histogram_add(msp->ms_deferhist[t], |
| sm->sm_shift, msp->ms_defer[t]); |
| } |
| } |
| |
| metaslab_aux_histogram_add(msp->ms_synchist, |
| sm->sm_shift, msp->ms_freeing); |
| } |
| |
| /* |
| * Called every time we are done syncing (writing to) the metaslab, |
| * i.e. at the end of each sync pass. |
| * [see the comment in metaslab_impl.h for ms_synchist, ms_deferhist] |
| */ |
| static void |
| metaslab_aux_histograms_update_done(metaslab_t *msp, boolean_t defer_allowed) |
| { |
| spa_t *spa = msp->ms_group->mg_vd->vdev_spa; |
| space_map_t *sm = msp->ms_sm; |
| |
| if (sm == NULL) { |
| /* |
| * We came here from metaslab_init() when creating/opening a |
| * pool, looking at a metaslab that hasn't had any allocations |
| * yet. |
| */ |
| return; |
| } |
| |
| /* |
| * This is similar to the actions that we take for the ms_freed |
| * and ms_defer trees in metaslab_sync_done(). |
| */ |
| uint64_t hist_index = spa_syncing_txg(spa) % TXG_DEFER_SIZE; |
| if (defer_allowed) { |
| bcopy(msp->ms_synchist, msp->ms_deferhist[hist_index], |
| sizeof (msp->ms_synchist)); |
| } else { |
| bzero(msp->ms_deferhist[hist_index], |
| sizeof (msp->ms_deferhist[hist_index])); |
| } |
| bzero(msp->ms_synchist, sizeof (msp->ms_synchist)); |
| } |
| |
| /* |
| * Ensure that the metaslab's weight and fragmentation are consistent |
| * with the contents of the histogram (either the range tree's histogram |
| * or the space map's depending whether the metaslab is loaded). |
| */ |
| static void |
| metaslab_verify_weight_and_frag(metaslab_t *msp) |
| { |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| |
| if ((zfs_flags & ZFS_DEBUG_METASLAB_VERIFY) == 0) |
| return; |
| |
| /* see comment in metaslab_verify_unflushed_changes() */ |
| if (msp->ms_group == NULL) |
| return; |
| |
| /* |
| * Devices being removed always return a weight of 0 and leave |
| * fragmentation and ms_max_size as is - there is nothing for |
| * us to verify here. |
| */ |
| vdev_t *vd = msp->ms_group->mg_vd; |
| if (vd->vdev_removing) |
| return; |
| |
| /* |
| * If the metaslab is dirty it probably means that we've done |
| * some allocations or frees that have changed our histograms |
| * and thus the weight. |
| */ |
| for (int t = 0; t < TXG_SIZE; t++) { |
| if (txg_list_member(&vd->vdev_ms_list, msp, t)) |
| return; |
| } |
| |
| /* |
| * This verification checks that our in-memory state is consistent |
| * with what's on disk. If the pool is read-only then there aren't |
| * any changes and we just have the initially-loaded state. |
| */ |
| if (!spa_writeable(msp->ms_group->mg_vd->vdev_spa)) |
| return; |
| |
| /* some extra verification for in-core tree if you can */ |
| if (msp->ms_loaded) { |
| range_tree_stat_verify(msp->ms_allocatable); |
| VERIFY(space_map_histogram_verify(msp->ms_sm, |
| msp->ms_allocatable)); |
| } |
| |
| uint64_t weight = msp->ms_weight; |
| uint64_t was_active = msp->ms_weight & METASLAB_ACTIVE_MASK; |
| boolean_t space_based = WEIGHT_IS_SPACEBASED(msp->ms_weight); |
| uint64_t frag = msp->ms_fragmentation; |
| uint64_t max_segsize = msp->ms_max_size; |
| |
| msp->ms_weight = 0; |
| msp->ms_fragmentation = 0; |
| msp->ms_max_size = 0; |
| |
| /* |
| * This function is used for verification purposes. Regardless of |
| * whether metaslab_weight() thinks this metaslab should be active or |
| * not, we want to ensure that the actual weight (and therefore the |
| * value of ms_weight) would be the same if it was to be recalculated |
| * at this point. |
| */ |
| msp->ms_weight = metaslab_weight(msp) | was_active; |
| |
| VERIFY3U(max_segsize, ==, msp->ms_max_size); |
| |
| /* |
| * If the weight type changed then there is no point in doing |
| * verification. Revert fields to their original values. |
| */ |
| if ((space_based && !WEIGHT_IS_SPACEBASED(msp->ms_weight)) || |
| (!space_based && WEIGHT_IS_SPACEBASED(msp->ms_weight))) { |
| msp->ms_fragmentation = frag; |
| msp->ms_weight = weight; |
| return; |
| } |
| |
| VERIFY3U(msp->ms_fragmentation, ==, frag); |
| VERIFY3U(msp->ms_weight, ==, weight); |
| } |
| |
| /* |
| * Wait for any in-progress metaslab loads to complete. |
| */ |
| static void |
| metaslab_load_wait(metaslab_t *msp) |
| { |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| |
| while (msp->ms_loading) { |
| ASSERT(!msp->ms_loaded); |
| cv_wait(&msp->ms_load_cv, &msp->ms_lock); |
| } |
| } |
| |
| static int |
| metaslab_load_impl(metaslab_t *msp) |
| { |
| int error = 0; |
| |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| ASSERT(msp->ms_loading); |
| ASSERT(!msp->ms_condensing); |
| |
| /* |
| * We temporarily drop the lock to unblock other operations while we |
| * are reading the space map. Therefore, metaslab_sync() and |
| * metaslab_sync_done() can run at the same time as we do. |
| * |
| * metaslab_sync() can append to the space map while we are loading. |
| * Therefore we load only entries that existed when we started the |
| * load. Additionally, metaslab_sync_done() has to wait for the load |
| * to complete because there are potential races like metaslab_load() |
| * loading parts of the space map that are currently being appended |
| * by metaslab_sync(). If we didn't, the ms_allocatable would have |
| * entries that metaslab_sync_done() would try to re-add later. |
| * |
| * That's why before dropping the lock we remember the synced length |
| * of the metaslab and read up to that point of the space map, |
| * ignoring entries appended by metaslab_sync() that happen after we |
| * drop the lock. |
| */ |
| uint64_t length = msp->ms_synced_length; |
| mutex_exit(&msp->ms_lock); |
| |
| if (msp->ms_sm != NULL) { |
| error = space_map_load_length(msp->ms_sm, msp->ms_allocatable, |
| SM_FREE, length); |
| } else { |
| /* |
| * The space map has not been allocated yet, so treat |
| * all the space in the metaslab as free and add it to the |
| * ms_allocatable tree. |
| */ |
| range_tree_add(msp->ms_allocatable, |
| msp->ms_start, msp->ms_size); |
| } |
| |
| /* |
| * We need to grab the ms_sync_lock to prevent metaslab_sync() from |
| * changing the ms_sm and the metaslab's range trees while we are |
| * about to use them and populate the ms_allocatable. The ms_lock |
| * is insufficient for this because metaslab_sync() doesn't hold |
| * the ms_lock while writing the ms_checkpointing tree to disk. |
| */ |
| mutex_enter(&msp->ms_sync_lock); |
| mutex_enter(&msp->ms_lock); |
| ASSERT(!msp->ms_condensing); |
| |
| if (error != 0) { |
| mutex_exit(&msp->ms_sync_lock); |
| return (error); |
| } |
| |
| ASSERT3P(msp->ms_group, !=, NULL); |
| msp->ms_loaded = B_TRUE; |
| |
| /* |
| * The ms_allocatable contains the segments that exist in the |
| * ms_defer trees [see ms_synced_length]. Thus we need to remove |
| * them from ms_allocatable as they will be added again in |
| * metaslab_sync_done(). |
| */ |
| for (int t = 0; t < TXG_DEFER_SIZE; t++) { |
| range_tree_walk(msp->ms_defer[t], |
| range_tree_remove, msp->ms_allocatable); |
| } |
| |
| /* |
| * Call metaslab_recalculate_weight_and_sort() now that the |
| * metaslab is loaded so we get the metaslab's real weight. |
| * |
| * Unless this metaslab was created with older software and |
| * has not yet been converted to use segment-based weight, we |
| * expect the new weight to be better or equal to the weight |
| * that the metaslab had while it was not loaded. This is |
| * because the old weight does not take into account the |
| * consolidation of adjacent segments between TXGs. [see |
| * comment for ms_synchist and ms_deferhist[] for more info] |
| */ |
| uint64_t weight = msp->ms_weight; |
| metaslab_recalculate_weight_and_sort(msp); |
| if (!WEIGHT_IS_SPACEBASED(weight)) |
| ASSERT3U(weight, <=, msp->ms_weight); |
| msp->ms_max_size = metaslab_block_maxsize(msp); |
| |
| spa_t *spa = msp->ms_group->mg_vd->vdev_spa; |
| metaslab_verify_space(msp, spa_syncing_txg(spa)); |
| mutex_exit(&msp->ms_sync_lock); |
| |
| return (0); |
| } |
| |
| int |
| metaslab_load(metaslab_t *msp) |
| { |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| |
| /* |
| * There may be another thread loading the same metaslab, if that's |
| * the case just wait until the other thread is done and return. |
| */ |
| metaslab_load_wait(msp); |
| if (msp->ms_loaded) |
| return (0); |
| VERIFY(!msp->ms_loading); |
| ASSERT(!msp->ms_condensing); |
| |
| msp->ms_loading = B_TRUE; |
| int error = metaslab_load_impl(msp); |
| msp->ms_loading = B_FALSE; |
| cv_broadcast(&msp->ms_load_cv); |
| |
| return (error); |
| } |
| |
| void |
| metaslab_unload(metaslab_t *msp) |
| { |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| |
| metaslab_verify_weight_and_frag(msp); |
| |
| range_tree_vacate(msp->ms_allocatable, NULL, NULL); |
| msp->ms_loaded = B_FALSE; |
| |
| msp->ms_activation_weight = 0; |
| msp->ms_weight &= ~METASLAB_ACTIVE_MASK; |
| msp->ms_max_size = 0; |
| |
| /* |
| * We explicitly recalculate the metaslab's weight based on its space |
| * map (as it is now not loaded). We want unload metaslabs to always |
| * have their weights calculated from the space map histograms, while |
| * loaded ones have it calculated from their in-core range tree |
| * [see metaslab_load()]. This way, the weight reflects the information |
| * available in-core, whether it is loaded or not |
| * |
| * If ms_group == NULL means that we came here from metaslab_fini(), |
| * at which point it doesn't make sense for us to do the recalculation |
| * and the sorting. |
| */ |
| if (msp->ms_group != NULL) |
| metaslab_recalculate_weight_and_sort(msp); |
| } |
| |
| static void |
| metaslab_space_update(vdev_t *vd, metaslab_class_t *mc, int64_t alloc_delta, |
| int64_t defer_delta, int64_t space_delta) |
| { |
| vdev_space_update(vd, alloc_delta, defer_delta, space_delta); |
| |
| ASSERT3P(vd->vdev_spa->spa_root_vdev, ==, vd->vdev_parent); |
| ASSERT(vd->vdev_ms_count != 0); |
| |
| metaslab_class_space_update(mc, alloc_delta, defer_delta, space_delta, |
| vdev_deflated_space(vd, space_delta)); |
| } |
| |
| int |
| metaslab_init(metaslab_group_t *mg, uint64_t id, uint64_t object, uint64_t txg, |
| metaslab_t **msp) |
| { |
| vdev_t *vd = mg->mg_vd; |
| spa_t *spa = vd->vdev_spa; |
| objset_t *mos = spa->spa_meta_objset; |
| metaslab_t *ms; |
| int error; |
| |
| ms = kmem_zalloc(sizeof (metaslab_t), KM_SLEEP); |
| mutex_init(&ms->ms_lock, NULL, MUTEX_DEFAULT, NULL); |
| mutex_init(&ms->ms_sync_lock, NULL, MUTEX_DEFAULT, NULL); |
| cv_init(&ms->ms_load_cv, NULL, CV_DEFAULT, NULL); |
| |
| ms->ms_id = id; |
| ms->ms_start = id << vd->vdev_ms_shift; |
| ms->ms_size = 1ULL << vd->vdev_ms_shift; |
| ms->ms_allocator = -1; |
| ms->ms_new = B_TRUE; |
| |
| /* |
| * We only open space map objects that already exist. All others |
| * will be opened when we finally allocate an object for it. |
| * |
| * Note: |
| * When called from vdev_expand(), we can't call into the DMU as |
| * we are holding the spa_config_lock as a writer and we would |
| * deadlock [see relevant comment in vdev_metaslab_init()]. in |
| * that case, the object parameter is zero though, so we won't |
| * call into the DMU. |
| */ |
| if (object != 0) { |
| error = space_map_open(&ms->ms_sm, mos, object, ms->ms_start, |
| ms->ms_size, vd->vdev_ashift); |
| |
| if (error != 0) { |
| kmem_free(ms, sizeof (metaslab_t)); |
| return (error); |
| } |
| |
| ASSERT(ms->ms_sm != NULL); |
| ms->ms_allocated_space = space_map_allocated(ms->ms_sm); |
| } |
| |
| /* |
| * We create the ms_allocatable here, but we don't create the |
| * other range trees until metaslab_sync_done(). This serves |
| * two purposes: it allows metaslab_sync_done() to detect the |
| * addition of new space; and for debugging, it ensures that |
| * we'd data fault on any attempt to use this metaslab before |
| * it's ready. |
| */ |
| ms->ms_allocatable = range_tree_create_impl(&rt_avl_ops, |
| &ms->ms_allocatable_by_size, metaslab_rangesize_compare, 0); |
| |
| ms->ms_trim = range_tree_create(NULL, NULL); |
| |
| metaslab_group_add(mg, ms); |
| metaslab_set_fragmentation(ms); |
| |
| /* |
| * If we're opening an existing pool (txg == 0) or creating |
| * a new one (txg == TXG_INITIAL), all space is available now. |
| * If we're adding space to an existing pool, the new space |
| * does not become available until after this txg has synced. |
| * The metaslab's weight will also be initialized when we sync |
| * out this txg. This ensures that we don't attempt to allocate |
| * from it before we have initialized it completely. |
| */ |
| if (txg <= TXG_INITIAL) { |
| metaslab_sync_done(ms, 0); |
| metaslab_space_update(vd, mg->mg_class, |
| metaslab_allocated_space(ms), 0, 0); |
| } |
| |
| /* |
| * If metaslab_debug_load is set and we're initializing a metaslab |
| * that has an allocated space map object then load the space map |
| * so that we can verify frees. |
| */ |
| if (metaslab_debug_load && ms->ms_sm != NULL) { |
| mutex_enter(&ms->ms_lock); |
| VERIFY0(metaslab_load(ms)); |
| mutex_exit(&ms->ms_lock); |
| } |
| |
| if (txg != 0) { |
| vdev_dirty(vd, 0, NULL, txg); |
| vdev_dirty(vd, VDD_METASLAB, ms, txg); |
| } |
| |
| *msp = ms; |
| |
| return (0); |
| } |
| |
| void |
| metaslab_fini(metaslab_t *msp) |
| { |
| metaslab_group_t *mg = msp->ms_group; |
| vdev_t *vd = mg->mg_vd; |
| |
| metaslab_group_remove(mg, msp); |
| |
| mutex_enter(&msp->ms_lock); |
| VERIFY(msp->ms_group == NULL); |
| metaslab_space_update(vd, mg->mg_class, |
| -metaslab_allocated_space(msp), 0, -msp->ms_size); |
| |
| space_map_close(msp->ms_sm); |
| |
| metaslab_unload(msp); |
| |
| range_tree_destroy(msp->ms_allocatable); |
| range_tree_destroy(msp->ms_freeing); |
| range_tree_destroy(msp->ms_freed); |
| |
| for (int t = 0; t < TXG_SIZE; t++) { |
| range_tree_destroy(msp->ms_allocating[t]); |
| } |
| |
| for (int t = 0; t < TXG_DEFER_SIZE; t++) { |
| range_tree_destroy(msp->ms_defer[t]); |
| } |
| ASSERT0(msp->ms_deferspace); |
| |
| range_tree_destroy(msp->ms_checkpointing); |
| |
| for (int t = 0; t < TXG_SIZE; t++) |
| ASSERT(!txg_list_member(&vd->vdev_ms_list, msp, t)); |
| |
| range_tree_vacate(msp->ms_trim, NULL, NULL); |
| range_tree_destroy(msp->ms_trim); |
| |
| mutex_exit(&msp->ms_lock); |
| cv_destroy(&msp->ms_load_cv); |
| mutex_destroy(&msp->ms_lock); |
| mutex_destroy(&msp->ms_sync_lock); |
| ASSERT3U(msp->ms_allocator, ==, -1); |
| |
| kmem_free(msp, sizeof (metaslab_t)); |
| } |
| |
| #define FRAGMENTATION_TABLE_SIZE 17 |
| |
| /* |
| * This table defines a segment size based fragmentation metric that will |
| * allow each metaslab to derive its own fragmentation value. This is done |
| * by calculating the space in each bucket of the spacemap histogram and |
| * multiplying that by the fragmentation metric in this table. Doing |
| * this for all buckets and dividing it by the total amount of free |
| * space in this metaslab (i.e. the total free space in all buckets) gives |
| * us the fragmentation metric. This means that a high fragmentation metric |
| * equates to most of the free space being comprised of small segments. |
| * Conversely, if the metric is low, then most of the free space is in |
| * large segments. A 10% change in fragmentation equates to approximately |
| * double the number of segments. |
| * |
| * This table defines 0% fragmented space using 16MB segments. Testing has |
| * shown that segments that are greater than or equal to 16MB do not suffer |
| * from drastic performance problems. Using this value, we derive the rest |
| * of the table. Since the fragmentation value is never stored on disk, it |
| * is possible to change these calculations in the future. |
| */ |
| int zfs_frag_table[FRAGMENTATION_TABLE_SIZE] = { |
| 100, /* 512B */ |
| 100, /* 1K */ |
| 98, /* 2K */ |
| 95, /* 4K */ |
| 90, /* 8K */ |
| 80, /* 16K */ |
| 70, /* 32K */ |
| 60, /* 64K */ |
| 50, /* 128K */ |
| 40, /* 256K */ |
| 30, /* 512K */ |
| 20, /* 1M */ |
| 15, /* 2M */ |
| 10, /* 4M */ |
| 5, /* 8M */ |
| 0 /* 16M */ |
| }; |
| |
| /* |
| * Calculate the metaslab's fragmentation metric and set ms_fragmentation. |
| * Setting this value to ZFS_FRAG_INVALID means that the metaslab has not |
| * been upgraded and does not support this metric. Otherwise, the return |
| * value should be in the range [0, 100]. |
| */ |
| static void |
| metaslab_set_fragmentation(metaslab_t *msp) |
| { |
| spa_t *spa = msp->ms_group->mg_vd->vdev_spa; |
| uint64_t fragmentation = 0; |
| uint64_t total = 0; |
| boolean_t feature_enabled = spa_feature_is_enabled(spa, |
| SPA_FEATURE_SPACEMAP_HISTOGRAM); |
| |
| if (!feature_enabled) { |
| msp->ms_fragmentation = ZFS_FRAG_INVALID; |
| return; |
| } |
| |
| /* |
| * A null space map means that the entire metaslab is free |
| * and thus is not fragmented. |
| */ |
| if (msp->ms_sm == NULL) { |
| msp->ms_fragmentation = 0; |
| return; |
| } |
| |
| /* |
| * If this metaslab's space map has not been upgraded, flag it |
| * so that we upgrade next time we encounter it. |
| */ |
| if (msp->ms_sm->sm_dbuf->db_size != sizeof (space_map_phys_t)) { |
| uint64_t txg = spa_syncing_txg(spa); |
| vdev_t *vd = msp->ms_group->mg_vd; |
| |
| /* |
| * If we've reached the final dirty txg, then we must |
| * be shutting down the pool. We don't want to dirty |
| * any data past this point so skip setting the condense |
| * flag. We can retry this action the next time the pool |
| * is imported. |
| */ |
| if (spa_writeable(spa) && txg < spa_final_dirty_txg(spa)) { |
| msp->ms_condense_wanted = B_TRUE; |
| vdev_dirty(vd, VDD_METASLAB, msp, txg + 1); |
| zfs_dbgmsg("txg %llu, requesting force condense: " |
| "ms_id %llu, vdev_id %llu", txg, msp->ms_id, |
| vd->vdev_id); |
| } |
| msp->ms_fragmentation = ZFS_FRAG_INVALID; |
| return; |
| } |
| |
| for (int i = 0; i < SPACE_MAP_HISTOGRAM_SIZE; i++) { |
| uint64_t space = 0; |
| uint8_t shift = msp->ms_sm->sm_shift; |
| |
| int idx = MIN(shift - SPA_MINBLOCKSHIFT + i, |
| FRAGMENTATION_TABLE_SIZE - 1); |
| |
| if (msp->ms_sm->sm_phys->smp_histogram[i] == 0) |
| continue; |
| |
| space = msp->ms_sm->sm_phys->smp_histogram[i] << (i + shift); |
| total += space; |
| |
| ASSERT3U(idx, <, FRAGMENTATION_TABLE_SIZE); |
| fragmentation += space * zfs_frag_table[idx]; |
| } |
| |
| if (total > 0) |
| fragmentation /= total; |
| ASSERT3U(fragmentation, <=, 100); |
| |
| msp->ms_fragmentation = fragmentation; |
| } |
| |
| /* |
| * Compute a weight -- a selection preference value -- for the given metaslab. |
| * This is based on the amount of free space, the level of fragmentation, |
| * the LBA range, and whether the metaslab is loaded. |
| */ |
| static uint64_t |
| metaslab_space_weight(metaslab_t *msp) |
| { |
| metaslab_group_t *mg = msp->ms_group; |
| vdev_t *vd = mg->mg_vd; |
| uint64_t weight, space; |
| |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| ASSERT(!vd->vdev_removing); |
| |
| /* |
| * The baseline weight is the metaslab's free space. |
| */ |
| space = msp->ms_size - metaslab_allocated_space(msp); |
| |
| if (metaslab_fragmentation_factor_enabled && |
| msp->ms_fragmentation != ZFS_FRAG_INVALID) { |
| /* |
| * Use the fragmentation information to inversely scale |
| * down the baseline weight. We need to ensure that we |
| * don't exclude this metaslab completely when it's 100% |
| * fragmented. To avoid this we reduce the fragmented value |
| * by 1. |
| */ |
| space = (space * (100 - (msp->ms_fragmentation - 1))) / 100; |
| |
| /* |
| * If space < SPA_MINBLOCKSIZE, then we will not allocate from |
| * this metaslab again. The fragmentation metric may have |
| * decreased the space to something smaller than |
| * SPA_MINBLOCKSIZE, so reset the space to SPA_MINBLOCKSIZE |
| * so that we can consume any remaining space. |
| */ |
| if (space > 0 && space < SPA_MINBLOCKSIZE) |
| space = SPA_MINBLOCKSIZE; |
| } |
| weight = space; |
| |
| /* |
| * Modern disks have uniform bit density and constant angular velocity. |
| * Therefore, the outer recording zones are faster (higher bandwidth) |
| * than the inner zones by the ratio of outer to inner track diameter, |
| * which is typically around 2:1. We account for this by assigning |
| * higher weight to lower metaslabs (multiplier ranging from 2x to 1x). |
| * In effect, this means that we'll select the metaslab with the most |
| * free bandwidth rather than simply the one with the most free space. |
| */ |
| if (!vd->vdev_nonrot && metaslab_lba_weighting_enabled) { |
| weight = 2 * weight - (msp->ms_id * weight) / vd->vdev_ms_count; |
| ASSERT(weight >= space && weight <= 2 * space); |
| } |
| |
| /* |
| * If this metaslab is one we're actively using, adjust its |
| * weight to make it preferable to any inactive metaslab so |
| * we'll polish it off. If the fragmentation on this metaslab |
| * has exceed our threshold, then don't mark it active. |
| */ |
| if (msp->ms_loaded && msp->ms_fragmentation != ZFS_FRAG_INVALID && |
| msp->ms_fragmentation <= zfs_metaslab_fragmentation_threshold) { |
| weight |= (msp->ms_weight & METASLAB_ACTIVE_MASK); |
| } |
| |
| WEIGHT_SET_SPACEBASED(weight); |
| return (weight); |
| } |
| |
| /* |
| * Return the weight of the specified metaslab, according to the segment-based |
| * weighting algorithm. The metaslab must be loaded. This function can |
| * be called within a sync pass since it relies only on the metaslab's |
| * range tree which is always accurate when the metaslab is loaded. |
| */ |
| static uint64_t |
| metaslab_weight_from_range_tree(metaslab_t *msp) |
| { |
| uint64_t weight = 0; |
| uint32_t segments = 0; |
| |
| ASSERT(msp->ms_loaded); |
| |
| for (int i = RANGE_TREE_HISTOGRAM_SIZE - 1; i >= SPA_MINBLOCKSHIFT; |
| i--) { |
| uint8_t shift = msp->ms_group->mg_vd->vdev_ashift; |
| int max_idx = SPACE_MAP_HISTOGRAM_SIZE + shift - 1; |
| |
| segments <<= 1; |
| segments += msp->ms_allocatable->rt_histogram[i]; |
| |
| /* |
| * The range tree provides more precision than the space map |
| * and must be downgraded so that all values fit within the |
| * space map's histogram. This allows us to compare loaded |
| * vs. unloaded metaslabs to determine which metaslab is |
| * considered "best". |
| */ |
| if (i > max_idx) |
| continue; |
| |
| if (segments != 0) { |
| WEIGHT_SET_COUNT(weight, segments); |
| WEIGHT_SET_INDEX(weight, i); |
| WEIGHT_SET_ACTIVE(weight, 0); |
| break; |
| } |
| } |
| return (weight); |
| } |
| |
| /* |
| * Calculate the weight based on the on-disk histogram. This should only |
| * be called after a sync pass has completely finished since the on-disk |
| * information is updated in metaslab_sync(). |
| */ |
| static uint64_t |
| metaslab_weight_from_spacemap(metaslab_t *msp) |
| { |
| space_map_t *sm = msp->ms_sm; |
| ASSERT(!msp->ms_loaded); |
| ASSERT(sm != NULL); |
| ASSERT3U(space_map_object(sm), !=, 0); |
| ASSERT3U(sm->sm_dbuf->db_size, ==, sizeof (space_map_phys_t)); |
| |
| /* |
| * Create a joint histogram from all the segments that have made |
| * it to the metaslab's space map histogram, that are not yet |
| * available for allocation because they are still in the freeing |
| * pipeline (e.g. freeing, freed, and defer trees). Then subtract |
| * these segments from the space map's histogram to get a more |
| * accurate weight. |
| */ |
| uint64_t deferspace_histogram[SPACE_MAP_HISTOGRAM_SIZE] = {0}; |
| for (int i = 0; i < SPACE_MAP_HISTOGRAM_SIZE; i++) |
| deferspace_histogram[i] += msp->ms_synchist[i]; |
| for (int t = 0; t < TXG_DEFER_SIZE; t++) { |
| for (int i = 0; i < SPACE_MAP_HISTOGRAM_SIZE; i++) { |
| deferspace_histogram[i] += msp->ms_deferhist[t][i]; |
| } |
| } |
| |
| uint64_t weight = 0; |
| for (int i = SPACE_MAP_HISTOGRAM_SIZE - 1; i >= 0; i--) { |
| ASSERT3U(sm->sm_phys->smp_histogram[i], >=, |
| deferspace_histogram[i]); |
| uint64_t count = |
| sm->sm_phys->smp_histogram[i] - deferspace_histogram[i]; |
| if (count != 0) { |
| WEIGHT_SET_COUNT(weight, count); |
| WEIGHT_SET_INDEX(weight, i + sm->sm_shift); |
| WEIGHT_SET_ACTIVE(weight, 0); |
| break; |
| } |
| } |
| return (weight); |
| } |
| |
| /* |
| * Compute a segment-based weight for the specified metaslab. The weight |
| * is determined by highest bucket in the histogram. The information |
| * for the highest bucket is encoded into the weight value. |
| */ |
| static uint64_t |
| metaslab_segment_weight(metaslab_t *msp) |
| { |
| metaslab_group_t *mg = msp->ms_group; |
| uint64_t weight = 0; |
| uint8_t shift = mg->mg_vd->vdev_ashift; |
| |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| |
| /* |
| * The metaslab is completely free. |
| */ |
| if (metaslab_allocated_space(msp) == 0) { |
| int idx = highbit64(msp->ms_size) - 1; |
| int max_idx = SPACE_MAP_HISTOGRAM_SIZE + shift - 1; |
| |
| if (idx < max_idx) { |
| WEIGHT_SET_COUNT(weight, 1ULL); |
| WEIGHT_SET_INDEX(weight, idx); |
| } else { |
| WEIGHT_SET_COUNT(weight, 1ULL << (idx - max_idx)); |
| WEIGHT_SET_INDEX(weight, max_idx); |
| } |
| WEIGHT_SET_ACTIVE(weight, 0); |
| ASSERT(!WEIGHT_IS_SPACEBASED(weight)); |
| |
| return (weight); |
| } |
| |
| ASSERT3U(msp->ms_sm->sm_dbuf->db_size, ==, sizeof (space_map_phys_t)); |
| |
| /* |
| * If the metaslab is fully allocated then just make the weight 0. |
| */ |
| if (metaslab_allocated_space(msp) == msp->ms_size) |
| return (0); |
| /* |
| * If the metaslab is already loaded, then use the range tree to |
| * determine the weight. Otherwise, we rely on the space map information |
| * to generate the weight. |
| */ |
| if (msp->ms_loaded) { |
| weight = metaslab_weight_from_range_tree(msp); |
| } else { |
| weight = metaslab_weight_from_spacemap(msp); |
| } |
| |
| /* |
| * If the metaslab was active the last time we calculated its weight |
| * then keep it active. We want to consume the entire region that |
| * is associated with this weight. |
| */ |
| if (msp->ms_activation_weight != 0 && weight != 0) |
| WEIGHT_SET_ACTIVE(weight, WEIGHT_GET_ACTIVE(msp->ms_weight)); |
| return (weight); |
| } |
| |
| /* |
| * Determine if we should attempt to allocate from this metaslab. If the |
| * metaslab has a maximum size then we can quickly determine if the desired |
| * allocation size can be satisfied. Otherwise, if we're using segment-based |
| * weighting then we can determine the maximum allocation that this metaslab |
| * can accommodate based on the index encoded in the weight. If we're using |
| * space-based weights then rely on the entire weight (excluding the weight |
| * type bit). |
| */ |
| boolean_t |
| metaslab_should_allocate(metaslab_t *msp, uint64_t asize) |
| { |
| if (msp->ms_max_size != 0) |
| return (msp->ms_max_size >= asize); |
| |
| boolean_t should_allocate; |
| if (!WEIGHT_IS_SPACEBASED(msp->ms_weight)) { |
| /* |
| * The metaslab segment weight indicates segments in the |
| * range [2^i, 2^(i+1)), where i is the index in the weight. |
| * Since the asize might be in the middle of the range, we |
| * should attempt the allocation if asize < 2^(i+1). |
| */ |
| should_allocate = (asize < |
| 1ULL << (WEIGHT_GET_INDEX(msp->ms_weight) + 1)); |
| } else { |
| should_allocate = (asize <= |
| (msp->ms_weight & ~METASLAB_WEIGHT_TYPE)); |
| } |
| |
| return (should_allocate); |
| } |
| static uint64_t |
| metaslab_weight(metaslab_t *msp) |
| { |
| vdev_t *vd = msp->ms_group->mg_vd; |
| spa_t *spa = vd->vdev_spa; |
| uint64_t weight; |
| |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| |
| /* |
| * If this vdev is in the process of being removed, there is nothing |
| * for us to do here. |
| */ |
| if (vd->vdev_removing) |
| return (0); |
| |
| metaslab_set_fragmentation(msp); |
| |
| /* |
| * Update the maximum size if the metaslab is loaded. This will |
| * ensure that we get an accurate maximum size if newly freed space |
| * has been added back into the free tree. |
| */ |
| if (msp->ms_loaded) |
| msp->ms_max_size = metaslab_block_maxsize(msp); |
| else |
| ASSERT0(msp->ms_max_size); |
| |
| /* |
| * Segment-based weighting requires space map histogram support. |
| */ |
| if (zfs_metaslab_segment_weight_enabled && |
| spa_feature_is_enabled(spa, SPA_FEATURE_SPACEMAP_HISTOGRAM) && |
| (msp->ms_sm == NULL || msp->ms_sm->sm_dbuf->db_size == |
| sizeof (space_map_phys_t))) { |
| weight = metaslab_segment_weight(msp); |
| } else { |
| weight = metaslab_space_weight(msp); |
| } |
| return (weight); |
| } |
| |
| void |
| metaslab_recalculate_weight_and_sort(metaslab_t *msp) |
| { |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| |
| /* note: we preserve the mask (e.g. indication of primary, etc..) */ |
| uint64_t was_active = msp->ms_weight & METASLAB_ACTIVE_MASK; |
| metaslab_group_sort(msp->ms_group, msp, |
| metaslab_weight(msp) | was_active); |
| } |
| |
| static int |
| metaslab_activate_allocator(metaslab_group_t *mg, metaslab_t *msp, |
| int allocator, uint64_t activation_weight) |
| { |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| |
| /* |
| * If we're activating for the claim code, we don't want to actually |
| * set the metaslab up for a specific allocator. |
| */ |
| if (activation_weight == METASLAB_WEIGHT_CLAIM) |
| return (0); |
| |
| metaslab_t **arr = (activation_weight == METASLAB_WEIGHT_PRIMARY ? |
| mg->mg_primaries : mg->mg_secondaries); |
| |
| mutex_enter(&mg->mg_lock); |
| if (arr[allocator] != NULL) { |
| mutex_exit(&mg->mg_lock); |
| return (EEXIST); |
| } |
| |
| arr[allocator] = msp; |
| ASSERT3S(msp->ms_allocator, ==, -1); |
| msp->ms_allocator = allocator; |
| msp->ms_primary = (activation_weight == METASLAB_WEIGHT_PRIMARY); |
| mutex_exit(&mg->mg_lock); |
| |
| return (0); |
| } |
| |
| static int |
| metaslab_activate(metaslab_t *msp, int allocator, uint64_t activation_weight) |
| { |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| |
| /* |
| * The current metaslab is already activated for us so there |
| * is nothing to do. Already activated though, doesn't mean |
| * that this metaslab is activated for our allocator nor our |
| * requested activation weight. The metaslab could have started |
| * as an active one for our allocator but changed allocators |
| * while we were waiting to grab its ms_lock or we stole it |
| * [see find_valid_metaslab()]. This means that there is a |
| * possibility of passivating a metaslab of another allocator |
| * or from a different activation mask, from this thread. |
| */ |
| if ((msp->ms_weight & METASLAB_ACTIVE_MASK) != 0) { |
| ASSERT(msp->ms_loaded); |
| return (0); |
| } |
| |
| int error = metaslab_load(msp); |
| if (error != 0) { |
| metaslab_group_sort(msp->ms_group, msp, 0); |
| return (error); |
| } |
| |
| /* |
| * When entering metaslab_load() we may have dropped the |
| * ms_lock because we were loading this metaslab, or we |
| * were waiting for another thread to load it for us. In |
| * that scenario, we recheck the weight of the metaslab |
| * to see if it was activated by another thread. |
| * |
| * If the metaslab was activated for another allocator or |
| * it was activated with a different activation weight (e.g. |
| * we wanted to make it a primary but it was activated as |
| * secondary) we return error (EBUSY). |
| * |
| * If the metaslab was activated for the same allocator |
| * and requested activation mask, skip activating it. |
| */ |
| if ((msp->ms_weight & METASLAB_ACTIVE_MASK) != 0) { |
| if (msp->ms_allocator != allocator) |
| return (EBUSY); |
| |
| if ((msp->ms_weight & activation_weight) == 0) |
| return (SET_ERROR(EBUSY)); |
| |
| EQUIV((activation_weight == METASLAB_WEIGHT_PRIMARY), |
| msp->ms_primary); |
| return (0); |
| } |
| |
| /* |
| * If the metaslab has literally 0 space, it will have weight 0. In |
| * that case, don't bother activating it. This can happen if the |
| * metaslab had space during find_valid_metaslab, but another thread |
| * loaded it and used all that space while we were waiting to grab the |
| * lock. |
| */ |
| if (msp->ms_weight == 0) { |
| ASSERT0(range_tree_space(msp->ms_allocatable)); |
| return (SET_ERROR(ENOSPC)); |
| } |
| |
| if ((error = metaslab_activate_allocator(msp->ms_group, msp, |
| allocator, activation_weight)) != 0) { |
| return (error); |
| } |
| |
| ASSERT0(msp->ms_activation_weight); |
| msp->ms_activation_weight = msp->ms_weight; |
| metaslab_group_sort(msp->ms_group, msp, |
| msp->ms_weight | activation_weight); |
| |
| ASSERT(msp->ms_loaded); |
| ASSERT(msp->ms_weight & METASLAB_ACTIVE_MASK); |
| |
| return (0); |
| } |
| |
| static void |
| metaslab_passivate_allocator(metaslab_group_t *mg, metaslab_t *msp, |
| uint64_t weight) |
| { |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| ASSERT(msp->ms_loaded); |
| |
| if (msp->ms_weight & METASLAB_WEIGHT_CLAIM) { |
| metaslab_group_sort(mg, msp, weight); |
| return; |
| } |
| |
| mutex_enter(&mg->mg_lock); |
| ASSERT3P(msp->ms_group, ==, mg); |
| ASSERT3S(0, <=, msp->ms_allocator); |
| ASSERT3U(msp->ms_allocator, <, mg->mg_allocators); |
| |
| if (msp->ms_primary) { |
| ASSERT3P(mg->mg_primaries[msp->ms_allocator], ==, msp); |
| ASSERT(msp->ms_weight & METASLAB_WEIGHT_PRIMARY); |
| mg->mg_primaries[msp->ms_allocator] = NULL; |
| } else { |
| ASSERT3P(mg->mg_secondaries[msp->ms_allocator], ==, msp); |
| ASSERT(msp->ms_weight & METASLAB_WEIGHT_SECONDARY); |
| mg->mg_secondaries[msp->ms_allocator] = NULL; |
| } |
| msp->ms_allocator = -1; |
| metaslab_group_sort_impl(mg, msp, weight); |
| mutex_exit(&mg->mg_lock); |
| } |
| |
| static void |
| metaslab_passivate(metaslab_t *msp, uint64_t weight) |
| { |
| ASSERTV(uint64_t size = weight & ~METASLAB_WEIGHT_TYPE); |
| |
| /* |
| * If size < SPA_MINBLOCKSIZE, then we will not allocate from |
| * this metaslab again. In that case, it had better be empty, |
| * or we would be leaving space on the table. |
| */ |
| ASSERT(!WEIGHT_IS_SPACEBASED(msp->ms_weight) || |
| size >= SPA_MINBLOCKSIZE || |
| range_tree_space(msp->ms_allocatable) == 0); |
| ASSERT0(weight & METASLAB_ACTIVE_MASK); |
| |
| ASSERT(msp->ms_activation_weight != 0); |
| msp->ms_activation_weight = 0; |
| metaslab_passivate_allocator(msp->ms_group, msp, weight); |
| ASSERT0(msp->ms_weight & METASLAB_ACTIVE_MASK); |
| } |
| |
| /* |
| * Segment-based metaslabs are activated once and remain active until |
| * we either fail an allocation attempt (similar to space-based metaslabs) |
| * or have exhausted the free space in zfs_metaslab_switch_threshold |
| * buckets since the metaslab was activated. This function checks to see |
| * if we've exhaused the zfs_metaslab_switch_threshold buckets in the |
| * metaslab and passivates it proactively. This will allow us to select a |
| * metaslab with a larger contiguous region, if any, remaining within this |
| * metaslab group. If we're in sync pass > 1, then we continue using this |
| * metaslab so that we don't dirty more block and cause more sync passes. |
| */ |
| void |
| metaslab_segment_may_passivate(metaslab_t *msp) |
| { |
| spa_t *spa = msp->ms_group->mg_vd->vdev_spa; |
| |
| if (WEIGHT_IS_SPACEBASED(msp->ms_weight) || spa_sync_pass(spa) > 1) |
| return; |
| |
| /* |
| * Since we are in the middle of a sync pass, the most accurate |
| * information that is accessible to us is the in-core range tree |
| * histogram; calculate the new weight based on that information. |
| */ |
| uint64_t weight = metaslab_weight_from_range_tree(msp); |
| int activation_idx = WEIGHT_GET_INDEX(msp->ms_activation_weight); |
| int current_idx = WEIGHT_GET_INDEX(weight); |
| |
| if (current_idx <= activation_idx - zfs_metaslab_switch_threshold) |
| metaslab_passivate(msp, weight); |
| } |
| |
| static void |
| metaslab_preload(void *arg) |
| { |
| metaslab_t *msp = arg; |
| spa_t *spa = msp->ms_group->mg_vd->vdev_spa; |
| fstrans_cookie_t cookie = spl_fstrans_mark(); |
| |
| ASSERT(!MUTEX_HELD(&msp->ms_group->mg_lock)); |
| |
| mutex_enter(&msp->ms_lock); |
| (void) metaslab_load(msp); |
| msp->ms_selected_txg = spa_syncing_txg(spa); |
| mutex_exit(&msp->ms_lock); |
| spl_fstrans_unmark(cookie); |
| } |
| |
| static void |
| metaslab_group_preload(metaslab_group_t *mg) |
| { |
| spa_t *spa = mg->mg_vd->vdev_spa; |
| metaslab_t *msp; |
| avl_tree_t *t = &mg->mg_metaslab_tree; |
| int m = 0; |
| |
| if (spa_shutting_down(spa) || !metaslab_preload_enabled) { |
| taskq_wait_outstanding(mg->mg_taskq, 0); |
| return; |
| } |
| |
| mutex_enter(&mg->mg_lock); |
| |
| /* |
| * Load the next potential metaslabs |
| */ |
| for (msp = avl_first(t); msp != NULL; msp = AVL_NEXT(t, msp)) { |
| ASSERT3P(msp->ms_group, ==, mg); |
| |
| /* |
| * We preload only the maximum number of metaslabs specified |
| * by metaslab_preload_limit. If a metaslab is being forced |
| * to condense then we preload it too. This will ensure |
| * that force condensing happens in the next txg. |
| */ |
| if (++m > metaslab_preload_limit && !msp->ms_condense_wanted) { |
| continue; |
| } |
| |
| VERIFY(taskq_dispatch(mg->mg_taskq, metaslab_preload, |
| msp, TQ_SLEEP) != TASKQID_INVALID); |
| } |
| mutex_exit(&mg->mg_lock); |
| } |
| |
| /* |
| * Determine if the space map's on-disk footprint is past our tolerance |
| * for inefficiency. We would like to use the following criteria to make |
| * our decision: |
| * |
| * 1. The size of the space map object should not dramatically increase as a |
| * result of writing out the free space range tree. |
| * |
| * 2. The minimal on-disk space map representation is zfs_condense_pct/100 |
| * times the size than the free space range tree representation |
| * (i.e. zfs_condense_pct = 110 and in-core = 1MB, minimal = 1.1MB). |
| * |
| * 3. The on-disk size of the space map should actually decrease. |
| * |
| * Unfortunately, we cannot compute the on-disk size of the space map in this |
| * context because we cannot accurately compute the effects of compression, etc. |
| * Instead, we apply the heuristic described in the block comment for |
| * zfs_metaslab_condense_block_threshold - we only condense if the space used |
| * is greater than a threshold number of blocks. |
| */ |
| static boolean_t |
| metaslab_should_condense(metaslab_t *msp) |
| { |
| space_map_t *sm = msp->ms_sm; |
| vdev_t *vd = msp->ms_group->mg_vd; |
| uint64_t vdev_blocksize = 1 << vd->vdev_ashift; |
| uint64_t current_txg = spa_syncing_txg(vd->vdev_spa); |
| |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| ASSERT(msp->ms_loaded); |
| |
| /* |
| * Allocations and frees in early passes are generally more space |
| * efficient (in terms of blocks described in space map entries) |
| * than the ones in later passes (e.g. we don't compress after |
| * sync pass 5) and condensing a metaslab multiple times in a txg |
| * could degrade performance. |
| * |
| * Thus we prefer condensing each metaslab at most once every txg at |
| * the earliest sync pass possible. If a metaslab is eligible for |
| * condensing again after being considered for condensing within the |
| * same txg, it will hopefully be dirty in the next txg where it will |
| * be condensed at an earlier pass. |
| */ |
| if (msp->ms_condense_checked_txg == current_txg) |
| return (B_FALSE); |
| msp->ms_condense_checked_txg = current_txg; |
| |
| /* |
| * We always condense metaslabs that are empty and metaslabs for |
| * which a condense request has been made. |
| */ |
| if (avl_is_empty(&msp->ms_allocatable_by_size) || |
| msp->ms_condense_wanted) |
| return (B_TRUE); |
| |
| uint64_t object_size = space_map_length(msp->ms_sm); |
| uint64_t optimal_size = space_map_estimate_optimal_size(sm, |
| msp->ms_allocatable, SM_NO_VDEVID); |
| |
| dmu_object_info_t doi; |
| dmu_object_info_from_db(sm->sm_dbuf, &doi); |
| uint64_t record_size = MAX(doi.doi_data_block_size, vdev_blocksize); |
| |
| return (object_size >= (optimal_size * zfs_condense_pct / 100) && |
| object_size > zfs_metaslab_condense_block_threshold * record_size); |
| } |
| |
| /* |
| * Condense the on-disk space map representation to its minimized form. |
| * The minimized form consists of a small number of allocations followed by |
| * the entries of the free range tree. |
| */ |
| static void |
| metaslab_condense(metaslab_t *msp, uint64_t txg, dmu_tx_t *tx) |
| { |
| range_tree_t *condense_tree; |
| space_map_t *sm = msp->ms_sm; |
| |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| ASSERT(msp->ms_loaded); |
| |
| |
| zfs_dbgmsg("condensing: txg %llu, msp[%llu] %px, vdev id %llu, " |
| "spa %s, smp size %llu, segments %lu, forcing condense=%s", txg, |
| msp->ms_id, msp, msp->ms_group->mg_vd->vdev_id, |
| msp->ms_group->mg_vd->vdev_spa->spa_name, |
| space_map_length(msp->ms_sm), |
| avl_numnodes(&msp->ms_allocatable->rt_root), |
| msp->ms_condense_wanted ? "TRUE" : "FALSE"); |
| |
| msp->ms_condense_wanted = B_FALSE; |
| |
| /* |
| * Create an range tree that is 100% allocated. We remove segments |
| * that have been freed in this txg, any deferred frees that exist, |
| * and any allocation in the future. Removing segments should be |
| * a relatively inexpensive operation since we expect these trees to |
| * have a small number of nodes. |
| */ |
| condense_tree = range_tree_create(NULL, NULL); |
| range_tree_add(condense_tree, msp->ms_start, msp->ms_size); |
| |
| range_tree_walk(msp->ms_freeing, range_tree_remove, condense_tree); |
| range_tree_walk(msp->ms_freed, range_tree_remove, condense_tree); |
| |
| for (int t = 0; t < TXG_DEFER_SIZE; t++) { |
| range_tree_walk(msp->ms_defer[t], |
| range_tree_remove, condense_tree); |
| } |
| |
| for (int t = 1; t < TXG_CONCURRENT_STATES; t++) { |
| range_tree_walk(msp->ms_allocating[(txg + t) & TXG_MASK], |
| range_tree_remove, condense_tree); |
| } |
| |
| /* |
| * We're about to drop the metaslab's lock thus allowing |
| * other consumers to change it's content. Set the |
| * metaslab's ms_condensing flag to ensure that |
| * allocations on this metaslab do not occur while we're |
| * in the middle of committing it to disk. This is only critical |
| * for ms_allocatable as all other range trees use per txg |
| * views of their content. |
| */ |
| msp->ms_condensing = B_TRUE; |
| |
| mutex_exit(&msp->ms_lock); |
| space_map_truncate(sm, zfs_metaslab_sm_blksz, tx); |
| |
| /* |
| * While we would ideally like to create a space map representation |
| * that consists only of allocation records, doing so can be |
| * prohibitively expensive because the in-core free tree can be |
| * large, and therefore computationally expensive to subtract |
| * from the condense_tree. Instead we sync out two trees, a cheap |
| * allocation only tree followed by the in-core free tree. While not |
| * optimal, this is typically close to optimal, and much cheaper to |
| * compute. |
| */ |
| space_map_write(sm, condense_tree, SM_ALLOC, SM_NO_VDEVID, tx); |
| range_tree_vacate(condense_tree, NULL, NULL); |
| range_tree_destroy(condense_tree); |
| |
| space_map_write(sm, msp->ms_allocatable, SM_FREE, SM_NO_VDEVID, tx); |
| mutex_enter(&msp->ms_lock); |
| msp->ms_condensing = B_FALSE; |
| } |
| |
| /* |
| * Write a metaslab to disk in the context of the specified transaction group. |
| */ |
| void |
| metaslab_sync(metaslab_t *msp, uint64_t txg) |
| { |
| metaslab_group_t *mg = msp->ms_group; |
| vdev_t *vd = mg->mg_vd; |
| spa_t *spa = vd->vdev_spa; |
| objset_t *mos = spa_meta_objset(spa); |
| range_tree_t *alloctree = msp->ms_allocating[txg & TXG_MASK]; |
| dmu_tx_t *tx; |
| uint64_t object = space_map_object(msp->ms_sm); |
| |
| ASSERT(!vd->vdev_ishole); |
| |
| /* |
| * This metaslab has just been added so there's no work to do now. |
| */ |
| if (msp->ms_freeing == NULL) { |
| ASSERT3P(alloctree, ==, NULL); |
| return; |
| } |
| |
| ASSERT3P(alloctree, !=, NULL); |
| ASSERT3P(msp->ms_freeing, !=, NULL); |
| ASSERT3P(msp->ms_freed, !=, NULL); |
| ASSERT3P(msp->ms_checkpointing, !=, NULL); |
| ASSERT3P(msp->ms_trim, !=, NULL); |
| |
| /* |
| * Normally, we don't want to process a metaslab if there are no |
| * allocations or frees to perform. However, if the metaslab is being |
| * forced to condense, it's loaded and we're not beyond the final |
| * dirty txg, we need to let it through. Not condensing beyond the |
| * final dirty txg prevents an issue where metaslabs that need to be |
| * condensed but were loaded for other reasons could cause a panic |
| * here. By only checking the txg in that branch of the conditional, |
| * we preserve the utility of the VERIFY statements in all other |
| * cases. |
| */ |
| if (range_tree_is_empty(alloctree) && |
| range_tree_is_empty(msp->ms_freeing) && |
| range_tree_is_empty(msp->ms_checkpointing) && |
| !(msp->ms_loaded && msp->ms_condense_wanted && |
| txg <= spa_final_dirty_txg(spa))) |
| return; |
| |
| |
| VERIFY(txg <= spa_final_dirty_txg(spa)); |
| |
| /* |
| * The only state that can actually be changing concurrently |
| * with metaslab_sync() is the metaslab's ms_allocatable. No |
| * other thread can be modifying this txg's alloc, freeing, |
| * freed, or space_map_phys_t. We drop ms_lock whenever we |
| * could call into the DMU, because the DMU can call down to |
| * us (e.g. via zio_free()) at any time. |
| * |
| * The spa_vdev_remove_thread() can be reading metaslab state |
| * concurrently, and it is locked out by the ms_sync_lock. |
| * Note that the ms_lock is insufficient for this, because it |
| * is dropped by space_map_write(). |
| */ |
| tx = dmu_tx_create_assigned(spa_get_dsl(spa), txg); |
| |
| if (msp->ms_sm == NULL) { |
| uint64_t new_object; |
| |
| new_object = space_map_alloc(mos, zfs_metaslab_sm_blksz, tx); |
| VERIFY3U(new_object, !=, 0); |
| |
| VERIFY0(space_map_open(&msp->ms_sm, mos, new_object, |
| msp->ms_start, msp->ms_size, vd->vdev_ashift)); |
| |
| ASSERT(msp->ms_sm != NULL); |
| ASSERT0(metaslab_allocated_space(msp)); |
| } |
| |
| if (!range_tree_is_empty(msp->ms_checkpointing) && |
| vd->vdev_checkpoint_sm == NULL) { |
| ASSERT(spa_has_checkpoint(spa)); |
| |
| uint64_t new_object = space_map_alloc(mos, |
| vdev_standard_sm_blksz, tx); |
| VERIFY3U(new_object, !=, 0); |
| |
| VERIFY0(space_map_open(&vd->vdev_checkpoint_sm, |
| mos, new_object, 0, vd->vdev_asize, vd->vdev_ashift)); |
| ASSERT3P(vd->vdev_checkpoint_sm, !=, NULL); |
| |
| /* |
| * We save the space map object as an entry in vdev_top_zap |
| * so it can be retrieved when the pool is reopened after an |
| * export or through zdb. |
| */ |
| VERIFY0(zap_add(vd->vdev_spa->spa_meta_objset, |
| vd->vdev_top_zap, VDEV_TOP_ZAP_POOL_CHECKPOINT_SM, |
| sizeof (new_object), 1, &new_object, tx)); |
| } |
| |
| mutex_enter(&msp->ms_sync_lock); |
| mutex_enter(&msp->ms_lock); |
| |
| /* |
| * Note: metaslab_condense() clears the space map's histogram. |
| * Therefore we must verify and remove this histogram before |
| * condensing. |
| */ |
| metaslab_group_histogram_verify(mg); |
| metaslab_class_histogram_verify(mg->mg_class); |
| metaslab_group_histogram_remove(mg, msp); |
| |
| if (msp->ms_loaded && metaslab_should_condense(msp)) { |
| metaslab_condense(msp, txg, tx); |
| } else { |
| mutex_exit(&msp->ms_lock); |
| space_map_write(msp->ms_sm, alloctree, SM_ALLOC, |
| SM_NO_VDEVID, tx); |
| space_map_write(msp->ms_sm, msp->ms_freeing, SM_FREE, |
| SM_NO_VDEVID, tx); |
| mutex_enter(&msp->ms_lock); |
| } |
| |
| msp->ms_allocated_space += range_tree_space(alloctree); |
| ASSERT3U(msp->ms_allocated_space, >=, |
| range_tree_space(msp->ms_freeing)); |
| msp->ms_allocated_space -= range_tree_space(msp->ms_freeing); |
| |
| if (!range_tree_is_empty(msp->ms_checkpointing)) { |
| ASSERT(spa_has_checkpoint(spa)); |
| ASSERT3P(vd->vdev_checkpoint_sm, !=, NULL); |
| |
| /* |
| * Since we are doing writes to disk and the ms_checkpointing |
| * tree won't be changing during that time, we drop the |
| * ms_lock while writing to the checkpoint space map. |
| */ |
| mutex_exit(&msp->ms_lock); |
| space_map_write(vd->vdev_checkpoint_sm, |
| msp->ms_checkpointing, SM_FREE, SM_NO_VDEVID, tx); |
| mutex_enter(&msp->ms_lock); |
| |
| spa->spa_checkpoint_info.sci_dspace += |
| range_tree_space(msp->ms_checkpointing); |
| vd->vdev_stat.vs_checkpoint_space += |
| range_tree_space(msp->ms_checkpointing); |
| ASSERT3U(vd->vdev_stat.vs_checkpoint_space, ==, |
| -space_map_allocated(vd->vdev_checkpoint_sm)); |
| |
| range_tree_vacate(msp->ms_checkpointing, NULL, NULL); |
| } |
| |
| if (msp->ms_loaded) { |
| /* |
| * When the space map is loaded, we have an accurate |
| * histogram in the range tree. This gives us an opportunity |
| * to bring the space map's histogram up-to-date so we clear |
| * it first before updating it. |
| */ |
| space_map_histogram_clear(msp->ms_sm); |
| space_map_histogram_add(msp->ms_sm, msp->ms_allocatable, tx); |
| |
| /* |
| * Since we've cleared the histogram we need to add back |
| * any free space that has already been processed, plus |
| * any deferred space. This allows the on-disk histogram |
| * to accurately reflect all free space even if some space |
| * is not yet available for allocation (i.e. deferred). |
| */ |
| space_map_histogram_add(msp->ms_sm, msp->ms_freed, tx); |
| |
| /* |
| * Add back any deferred free space that has not been |
| * added back into the in-core free tree yet. This will |
| * ensure that we don't end up with a space map histogram |
| * that is completely empty unless the metaslab is fully |
| * allocated. |
| */ |
| for (int t = 0; t < TXG_DEFER_SIZE; t++) { |
| space_map_histogram_add(msp->ms_sm, |
| msp->ms_defer[t], tx); |
| } |
| } |
| |
| /* |
| * Always add the free space from this sync pass to the space |
| * map histogram. We want to make sure that the on-disk histogram |
| * accounts for all free space. If the space map is not loaded, |
| * then we will lose some accuracy but will correct it the next |
| * time we load the space map. |
| */ |
| space_map_histogram_add(msp->ms_sm, msp->ms_freeing, tx); |
| metaslab_aux_histograms_update(msp); |
| |
| metaslab_group_histogram_add(mg, msp); |
| metaslab_group_histogram_verify(mg); |
| metaslab_class_histogram_verify(mg->mg_class); |
| |
| /* |
| * For sync pass 1, we avoid traversing this txg's free range tree |
| * and instead will just swap the pointers for freeing and freed. |
| * We can safely do this since the freed_tree is guaranteed to be |
| * empty on the initial pass. |
| */ |
| if (spa_sync_pass(spa) == 1) { |
| range_tree_swap(&msp->ms_freeing, &msp->ms_freed); |
| ASSERT0(msp->ms_allocated_this_txg); |
| } else { |
| range_tree_vacate(msp->ms_freeing, |
| range_tree_add, msp->ms_freed); |
| } |
| msp->ms_allocated_this_txg += range_tree_space(alloctree); |
| range_tree_vacate(alloctree, NULL, NULL); |
| |
| ASSERT0(range_tree_space(msp->ms_allocating[txg & TXG_MASK])); |
| ASSERT0(range_tree_space(msp->ms_allocating[TXG_CLEAN(txg) |
| & TXG_MASK])); |
| ASSERT0(range_tree_space(msp->ms_freeing)); |
| ASSERT0(range_tree_space(msp->ms_checkpointing)); |
| |
| mutex_exit(&msp->ms_lock); |
| |
| if (object != space_map_object(msp->ms_sm)) { |
| object = space_map_object(msp->ms_sm); |
| dmu_write(mos, vd->vdev_ms_array, sizeof (uint64_t) * |
| msp->ms_id, sizeof (uint64_t), &object, tx); |
| } |
| mutex_exit(&msp->ms_sync_lock); |
| dmu_tx_commit(tx); |
| } |
| |
| void |
| metaslab_potentially_unload(metaslab_t *msp, uint64_t txg) |
| { |
| /* |
| * If the metaslab is loaded and we've not tried to load or allocate |
| * from it in 'metaslab_unload_delay' txgs, then unload it. |
| */ |
| if (msp->ms_loaded && |
| msp->ms_disabled == 0 && |
| msp->ms_selected_txg + metaslab_unload_delay < txg) { |
| for (int t = 1; t < TXG_CONCURRENT_STATES; t++) { |
| VERIFY0(range_tree_space( |
| msp->ms_allocating[(txg + t) & TXG_MASK])); |
| } |
| if (msp->ms_allocator != -1) { |
| metaslab_passivate(msp, msp->ms_weight & |
| ~METASLAB_ACTIVE_MASK); |
| } |
| |
| if (!metaslab_debug_unload) |
| metaslab_unload(msp); |
| } |
| } |
| |
| /* |
| * Called after a transaction group has completely synced to mark |
| * all of the metaslab's free space as usable. |
| */ |
| void |
| metaslab_sync_done(metaslab_t *msp, uint64_t txg) |
| { |
| metaslab_group_t *mg = msp->ms_group; |
| vdev_t *vd = mg->mg_vd; |
| spa_t *spa = vd->vdev_spa; |
| range_tree_t **defer_tree; |
| int64_t alloc_delta, defer_delta; |
| boolean_t defer_allowed = B_TRUE; |
| |
| ASSERT(!vd->vdev_ishole); |
| |
| mutex_enter(&msp->ms_lock); |
| |
| /* |
| * If this metaslab is just becoming available, initialize its |
| * range trees and add its capacity to the vdev. |
| */ |
| if (msp->ms_freed == NULL) { |
| for (int t = 0; t < TXG_SIZE; t++) { |
| ASSERT(msp->ms_allocating[t] == NULL); |
| |
| msp->ms_allocating[t] = range_tree_create(NULL, NULL); |
| } |
| |
| ASSERT3P(msp->ms_freeing, ==, NULL); |
| msp->ms_freeing = range_tree_create(NULL, NULL); |
| |
| ASSERT3P(msp->ms_freed, ==, NULL); |
| msp->ms_freed = range_tree_create(NULL, NULL); |
| |
| for (int t = 0; t < TXG_DEFER_SIZE; t++) { |
| ASSERT(msp->ms_defer[t] == NULL); |
| |
| msp->ms_defer[t] = range_tree_create(NULL, NULL); |
| } |
| |
| ASSERT3P(msp->ms_checkpointing, ==, NULL); |
| msp->ms_checkpointing = range_tree_create(NULL, NULL); |
| |
| metaslab_space_update(vd, mg->mg_class, 0, 0, msp->ms_size); |
| } |
| ASSERT0(range_tree_space(msp->ms_freeing)); |
| ASSERT0(range_tree_space(msp->ms_checkpointing)); |
| |
| defer_tree = &msp->ms_defer[txg % TXG_DEFER_SIZE]; |
| |
| uint64_t free_space = metaslab_class_get_space(spa_normal_class(spa)) - |
| metaslab_class_get_alloc(spa_normal_class(spa)); |
| if (free_space <= spa_get_slop_space(spa) || vd->vdev_removing) { |
| defer_allowed = B_FALSE; |
| } |
| |
| defer_delta = 0; |
| alloc_delta = msp->ms_allocated_this_txg - |
| range_tree_space(msp->ms_freed); |
| if (defer_allowed) { |
| defer_delta = range_tree_space(msp->ms_freed) - |
| range_tree_space(*defer_tree); |
| } else { |
| defer_delta -= range_tree_space(*defer_tree); |
| } |
| |
| metaslab_space_update(vd, mg->mg_class, alloc_delta + defer_delta, |
| defer_delta, 0); |
| |
| /* |
| * If there's a metaslab_load() in progress, wait for it to complete |
| * so that we have a consistent view of the in-core space map. |
| */ |
| metaslab_load_wait(msp); |
| |
| /* |
| * When auto-trimming is enabled, free ranges which are added to |
| * ms_allocatable are also be added to ms_trim. The ms_trim tree is |
| * periodically consumed by the vdev_autotrim_thread() which issues |
| * trims for all ranges and then vacates the tree. The ms_trim tree |
| * can be discarded at any time with the sole consequence of recent |
| * frees not being trimmed. |
| */ |
| if (spa_get_autotrim(spa) == SPA_AUTOTRIM_ON) { |
| range_tree_walk(*defer_tree, range_tree_add, msp->ms_trim); |
| if (!defer_allowed) { |
| range_tree_walk(msp->ms_freed, range_tree_add, |
| msp->ms_trim); |
| } |
| } else { |
| range_tree_vacate(msp->ms_trim, NULL, NULL); |
| } |
| |
| /* |
| * Move the frees from the defer_tree back to the free |
| * range tree (if it's loaded). Swap the freed_tree and |
| * the defer_tree -- this is safe to do because we've |
| * just emptied out the defer_tree. |
| */ |
| range_tree_vacate(*defer_tree, |
| msp->ms_loaded ? range_tree_add : NULL, msp->ms_allocatable); |
| if (defer_allowed) { |
| range_tree_swap(&msp->ms_freed, defer_tree); |
| } else { |
| range_tree_vacate(msp->ms_freed, |
| msp->ms_loaded ? range_tree_add : NULL, |
| msp->ms_allocatable); |
| } |
| |
| msp->ms_synced_length = space_map_length(msp->ms_sm); |
| |
| msp->ms_deferspace += defer_delta; |
| ASSERT3S(msp->ms_deferspace, >=, 0); |
| ASSERT3S(msp->ms_deferspace, <=, msp->ms_size); |
| if (msp->ms_deferspace != 0) { |
| /* |
| * Keep syncing this metaslab until all deferred frees |
| * are back in circulation. |
| */ |
| vdev_dirty(vd, VDD_METASLAB, msp, txg + 1); |
| } |
| metaslab_aux_histograms_update_done(msp, defer_allowed); |
| |
| if (msp->ms_new) { |
| msp->ms_new = B_FALSE; |
| mutex_enter(&mg->mg_lock); |
| mg->mg_ms_ready++; |
| mutex_exit(&mg->mg_lock); |
| } |
| |
| /* |
| * Re-sort metaslab within its group now that we've adjusted |
| * its allocatable space. |
| */ |
| metaslab_recalculate_weight_and_sort(msp); |
| |
| ASSERT0(range_tree_space(msp->ms_allocating[txg & TXG_MASK])); |
| ASSERT0(range_tree_space(msp->ms_freeing)); |
| ASSERT0(range_tree_space(msp->ms_freed)); |
| ASSERT0(range_tree_space(msp->ms_checkpointing)); |
| |
| msp->ms_allocated_this_txg = 0; |
| mutex_exit(&msp->ms_lock); |
| } |
| |
| void |
| metaslab_sync_reassess(metaslab_group_t *mg) |
| { |
| spa_t *spa = mg->mg_class->mc_spa; |
| |
| spa_config_enter(spa, SCL_ALLOC, FTAG, RW_READER); |
| metaslab_group_alloc_update(mg); |
| mg->mg_fragmentation = metaslab_group_fragmentation(mg); |
| |
| /* |
| * Preload the next potential metaslabs but only on active |
| * metaslab groups. We can get into a state where the metaslab |
| * is no longer active since we dirty metaslabs as we remove a |
| * a device, thus potentially making the metaslab group eligible |
| * for preloading. |
| */ |
| if (mg->mg_activation_count > 0) { |
| metaslab_group_preload(mg); |
| } |
| spa_config_exit(spa, SCL_ALLOC, FTAG); |
| } |
| |
| /* |
| * When writing a ditto block (i.e. more than one DVA for a given BP) on |
| * the same vdev as an existing DVA of this BP, then try to allocate it |
| * on a different metaslab than existing DVAs (i.e. a unique metaslab). |
| */ |
| static boolean_t |
| metaslab_is_unique(metaslab_t *msp, dva_t *dva) |
| { |
| uint64_t dva_ms_id; |
| |
| if (DVA_GET_ASIZE(dva) == 0) |
| return (B_TRUE); |
| |
| if (msp->ms_group->mg_vd->vdev_id != DVA_GET_VDEV(dva)) |
| return (B_TRUE); |
| |
| dva_ms_id = DVA_GET_OFFSET(dva) >> msp->ms_group->mg_vd->vdev_ms_shift; |
| |
| return (msp->ms_id != dva_ms_id); |
| } |
| |
| /* |
| * ========================================================================== |
| * Metaslab allocation tracing facility |
| * ========================================================================== |
| */ |
| #ifdef _METASLAB_TRACING |
| kstat_t *metaslab_trace_ksp; |
| kstat_named_t metaslab_trace_over_limit; |
| |
| void |
| metaslab_alloc_trace_init(void) |
| { |
| ASSERT(metaslab_alloc_trace_cache == NULL); |
| metaslab_alloc_trace_cache = kmem_cache_create( |
| "metaslab_alloc_trace_cache", sizeof (metaslab_alloc_trace_t), |
| 0, NULL, NULL, NULL, NULL, NULL, 0); |
| metaslab_trace_ksp = kstat_create("zfs", 0, "metaslab_trace_stats", |
| "misc", KSTAT_TYPE_NAMED, 1, KSTAT_FLAG_VIRTUAL); |
| if (metaslab_trace_ksp != NULL) { |
| metaslab_trace_ksp->ks_data = &metaslab_trace_over_limit; |
| kstat_named_init(&metaslab_trace_over_limit, |
| "metaslab_trace_over_limit", KSTAT_DATA_UINT64); |
| kstat_install(metaslab_trace_ksp); |
| } |
| } |
| |
| void |
| metaslab_alloc_trace_fini(void) |
| { |
| if (metaslab_trace_ksp != NULL) { |
| kstat_delete(metaslab_trace_ksp); |
| metaslab_trace_ksp = NULL; |
| } |
| kmem_cache_destroy(metaslab_alloc_trace_cache); |
| metaslab_alloc_trace_cache = NULL; |
| } |
| |
| /* |
| * Add an allocation trace element to the allocation tracing list. |
| */ |
| static void |
| metaslab_trace_add(zio_alloc_list_t *zal, metaslab_group_t *mg, |
| metaslab_t *msp, uint64_t psize, uint32_t dva_id, uint64_t offset, |
| int allocator) |
| { |
| metaslab_alloc_trace_t *mat; |
| |
| if (!metaslab_trace_enabled) |
| return; |
| |
| /* |
| * When the tracing list reaches its maximum we remove |
| * the second element in the list before adding a new one. |
| * By removing the second element we preserve the original |
| * entry as a clue to what allocations steps have already been |
| * performed. |
| */ |
| if (zal->zal_size == metaslab_trace_max_entries) { |
| metaslab_alloc_trace_t *mat_next; |
| #ifdef DEBUG |
| panic("too many entries in allocation list"); |
| #endif |
| atomic_inc_64(&metaslab_trace_over_limit.value.ui64); |
| zal->zal_size--; |
| mat_next = list_next(&zal->zal_list, list_head(&zal->zal_list)); |
| list_remove(&zal->zal_list, mat_next); |
| kmem_cache_free(metaslab_alloc_trace_cache, mat_next); |
| } |
| |
| mat = kmem_cache_alloc(metaslab_alloc_trace_cache, KM_SLEEP); |
| list_link_init(&mat->mat_list_node); |
| mat->mat_mg = mg; |
| mat->mat_msp = msp; |
| mat->mat_size = psize; |
| mat->mat_dva_id = dva_id; |
| mat->mat_offset = offset; |
| mat->mat_weight = 0; |
| mat->mat_allocator = allocator; |
| |
| if (msp != NULL) |
| mat->mat_weight = msp->ms_weight; |
| |
| /* |
| * The list is part of the zio so locking is not required. Only |
| * a single thread will perform allocations for a given zio. |
| */ |
| list_insert_tail(&zal->zal_list, mat); |
| zal->zal_size++; |
| |
| ASSERT3U(zal->zal_size, <=, metaslab_trace_max_entries); |
| } |
| |
| void |
| metaslab_trace_init(zio_alloc_list_t *zal) |
| { |
| list_create(&zal->zal_list, sizeof (metaslab_alloc_trace_t), |
| offsetof(metaslab_alloc_trace_t, mat_list_node)); |
| zal->zal_size = 0; |
| } |
| |
| void |
| metaslab_trace_fini(zio_alloc_list_t *zal) |
| { |
| metaslab_alloc_trace_t *mat; |
| |
| while ((mat = list_remove_head(&zal->zal_list)) != NULL) |
| kmem_cache_free(metaslab_alloc_trace_cache, mat); |
| list_destroy(&zal->zal_list); |
| zal->zal_size = 0; |
| } |
| #else |
| |
| #define metaslab_trace_add(zal, mg, msp, psize, id, off, alloc) |
| |
| void |
| metaslab_alloc_trace_init(void) |
| { |
| } |
| |
| void |
| metaslab_alloc_trace_fini(void) |
| { |
| } |
| |
| void |
| metaslab_trace_init(zio_alloc_list_t *zal) |
| { |
| } |
| |
| void |
| metaslab_trace_fini(zio_alloc_list_t *zal) |
| { |
| } |
| |
| #endif /* _METASLAB_TRACING */ |
| |
| /* |
| * ========================================================================== |
| * Metaslab block operations |
| * ========================================================================== |
| */ |
| |
| static void |
| metaslab_group_alloc_increment(spa_t *spa, uint64_t vdev, void *tag, int flags, |
| int allocator) |
| { |
| if (!(flags & METASLAB_ASYNC_ALLOC) || |
| (flags & METASLAB_DONT_THROTTLE)) |
| return; |
| |
| metaslab_group_t *mg = vdev_lookup_top(spa, vdev)->vdev_mg; |
| if (!mg->mg_class->mc_alloc_throttle_enabled) |
| return; |
| |
| (void) zfs_refcount_add(&mg->mg_alloc_queue_depth[allocator], tag); |
| } |
| |
| static void |
| metaslab_group_increment_qdepth(metaslab_group_t *mg, int allocator) |
| { |
| uint64_t max = mg->mg_max_alloc_queue_depth; |
| uint64_t cur = mg->mg_cur_max_alloc_queue_depth[allocator]; |
| while (cur < max) { |
| if (atomic_cas_64(&mg->mg_cur_max_alloc_queue_depth[allocator], |
| cur, cur + 1) == cur) { |
| atomic_inc_64( |
| &mg->mg_class->mc_alloc_max_slots[allocator]); |
| return; |
| } |
| cur = mg->mg_cur_max_alloc_queue_depth[allocator]; |
| } |
| } |
| |
| void |
| metaslab_group_alloc_decrement(spa_t *spa, uint64_t vdev, void *tag, int flags, |
| int allocator, boolean_t io_complete) |
| { |
| if (!(flags & METASLAB_ASYNC_ALLOC) || |
| (flags & METASLAB_DONT_THROTTLE)) |
| return; |
| |
| metaslab_group_t *mg = vdev_lookup_top(spa, vdev)->vdev_mg; |
| if (!mg->mg_class->mc_alloc_throttle_enabled) |
| return; |
| |
| (void) zfs_refcount_remove(&mg->mg_alloc_queue_depth[allocator], tag); |
| if (io_complete) |
| metaslab_group_increment_qdepth(mg, allocator); |
| } |
| |
| void |
| metaslab_group_alloc_verify(spa_t *spa, const blkptr_t *bp, void *tag, |
| int allocator) |
| { |
| #ifdef ZFS_DEBUG |
| const dva_t *dva = bp->blk_dva; |
| int ndvas = BP_GET_NDVAS(bp); |
| |
| for (int d = 0; d < ndvas; d++) { |
| uint64_t vdev = DVA_GET_VDEV(&dva[d]); |
| metaslab_group_t *mg = vdev_lookup_top(spa, vdev)->vdev_mg; |
| VERIFY(zfs_refcount_not_held( |
| &mg->mg_alloc_queue_depth[allocator], tag)); |
| } |
| #endif |
| } |
| |
| static uint64_t |
| metaslab_block_alloc(metaslab_t *msp, uint64_t size, uint64_t txg) |
| { |
| uint64_t start; |
| range_tree_t *rt = msp->ms_allocatable; |
| metaslab_class_t *mc = msp->ms_group->mg_class; |
| |
| VERIFY(!msp->ms_condensing); |
| VERIFY0(msp->ms_disabled); |
| |
| start = mc->mc_ops->msop_alloc(msp, size); |
| if (start != -1ULL) { |
| metaslab_group_t *mg = msp->ms_group; |
| vdev_t *vd = mg->mg_vd; |
| |
| VERIFY0(P2PHASE(start, 1ULL << vd->vdev_ashift)); |
| VERIFY0(P2PHASE(size, 1ULL << vd->vdev_ashift)); |
| VERIFY3U(range_tree_space(rt) - size, <=, msp->ms_size); |
| range_tree_remove(rt, start, size); |
| range_tree_clear(msp->ms_trim, start, size); |
| |
| if (range_tree_is_empty(msp->ms_allocating[txg & TXG_MASK])) |
| vdev_dirty(mg->mg_vd, VDD_METASLAB, msp, txg); |
| |
| range_tree_add(msp->ms_allocating[txg & TXG_MASK], start, size); |
| |
| /* Track the last successful allocation */ |
| msp->ms_alloc_txg = txg; |
| metaslab_verify_space(msp, txg); |
| } |
| |
| /* |
| * Now that we've attempted the allocation we need to update the |
| * metaslab's maximum block size since it may have changed. |
| */ |
| msp->ms_max_size = metaslab_block_maxsize(msp); |
| return (start); |
| } |
| |
| /* |
| * Find the metaslab with the highest weight that is less than what we've |
| * already tried. In the common case, this means that we will examine each |
| * metaslab at most once. Note that concurrent callers could reorder metaslabs |
| * by activation/passivation once we have dropped the mg_lock. If a metaslab is |
| * activated by another thread, and we fail to allocate from the metaslab we |
| * have selected, we may not try the newly-activated metaslab, and instead |
| * activate another metaslab. This is not optimal, but generally does not cause |
| * any problems (a possible exception being if every metaslab is completely full |
| * except for the the newly-activated metaslab which we fail to examine). |
| */ |
| static metaslab_t * |
| find_valid_metaslab(metaslab_group_t *mg, uint64_t activation_weight, |
| dva_t *dva, int d, boolean_t want_unique, uint64_t asize, int allocator, |
| zio_alloc_list_t *zal, metaslab_t *search, boolean_t *was_active) |
| { |
| avl_index_t idx; |
| avl_tree_t *t = &mg->mg_metaslab_tree; |
| metaslab_t *msp = avl_find(t, search, &idx); |
| if (msp == NULL) |
| msp = avl_nearest(t, idx, AVL_AFTER); |
| |
| for (; msp != NULL; msp = AVL_NEXT(t, msp)) { |
| int i; |
| if (!metaslab_should_allocate(msp, asize)) { |
| metaslab_trace_add(zal, mg, msp, asize, d, |
| TRACE_TOO_SMALL, allocator); |
| continue; |
| } |
| |
| /* |
| * If the selected metaslab is condensing or disabled, |
| * skip it. |
| */ |
| if (msp->ms_condensing || msp->ms_disabled > 0) |
| continue; |
| |
| *was_active = msp->ms_allocator != -1; |
| /* |
| * If we're activating as primary, this is our first allocation |
| * from this disk, so we don't need to check how close we are. |
| * If the metaslab under consideration was already active, |
| * we're getting desperate enough to steal another allocator's |
| * metaslab, so we still don't care about distances. |
| */ |
| if (activation_weight == METASLAB_WEIGHT_PRIMARY || *was_active) |
| break; |
| |
| for (i = 0; i < d; i++) { |
| if (want_unique && |
| !metaslab_is_unique(msp, &dva[i])) |
| break; /* try another metaslab */ |
| } |
| if (i == d) |
| break; |
| } |
| |
| if (msp != NULL) { |
| search->ms_weight = msp->ms_weight; |
| search->ms_start = msp->ms_start + 1; |
| search->ms_allocator = msp->ms_allocator; |
| search->ms_primary = msp->ms_primary; |
| } |
| return (msp); |
| } |
| |
| void |
| metaslab_active_mask_verify(metaslab_t *msp) |
| { |
| ASSERT(MUTEX_HELD(&msp->ms_lock)); |
| |
| if ((zfs_flags & ZFS_DEBUG_METASLAB_VERIFY) == 0) |
| return; |
| |
| if ((msp->ms_weight & METASLAB_ACTIVE_MASK) == 0) |
| return; |
| |
| if (msp->ms_weight & METASLAB_WEIGHT_PRIMARY) { |
| VERIFY0(msp->ms_weight & METASLAB_WEIGHT_SECONDARY); |
| VERIFY0(msp->ms_weight & METASLAB_WEIGHT_CLAIM); |
| VERIFY3S(msp->ms_allocator, !=, -1); |
| VERIFY(msp->ms_primary); |
| return; |
| } |
| |
| if (msp->ms_weight & METASLAB_WEIGHT_SECONDARY) { |
| VERIFY0(msp->ms_weight & METASLAB_WEIGHT_PRIMARY); |
| VERIFY0(msp->ms_weight & METASLAB_WEIGHT_CLAIM); |
| VERIFY3S(msp->ms_allocator, !=, -1); |
| VERIFY(!msp->ms_primary); |
| return; |
| } |
| |
| if (msp->ms_weight & METASLAB_WEIGHT_CLAIM) { |
| VERIFY0(msp->ms_weight & METASLAB_WEIGHT_PRIMARY); |
| VERIFY0(msp->ms_weight & METASLAB_WEIGHT_SECONDARY); |
| VERIFY3S(msp->ms_allocator, ==, -1); |
| return; |
| } |
| } |
| |
| /* ARGSUSED */ |
| static uint64_t |
| metaslab_group_alloc_normal(metaslab_group_t *mg, zio_alloc_list_t *zal, |
| uint64_t asize, uint64_t txg, boolean_t want_unique, dva_t *dva, |
| int d, int allocator) |
| { |
| metaslab_t *msp = NULL; |
| uint64_t offset = -1ULL; |
| |
| uint64_t activation_weight = METASLAB_WEIGHT_PRIMARY; |
| for (int i = 0; i < d; i++) { |
| if (activation_weight == METASLAB_WEIGHT_PRIMARY && |
| DVA_GET_VDEV(&dva[i]) == mg->mg_vd->vdev_id) { |
| activation_weight = METASLAB_WEIGHT_SECONDARY; |
| } else if (activation_weight == METASLAB_WEIGHT_SECONDARY && |
| DVA_GET_VDEV(&dva[i]) == mg->mg_vd->vdev_id) { |
| activation_weight = METASLAB_WEIGHT_CLAIM; |
| break; |
| } |
| } |
| |
| /* |
| * If we don't have enough metaslabs active to fill the entire array, we |
| * just use the 0th slot. |
| */ |
| if (mg->mg_ms_ready < mg->mg_allocators * 3) |
| allocator = 0; |
| |
| ASSERT3U(mg->mg_vd->vdev_ms_count, >=, 2); |
| |
| metaslab_t *search = kmem_alloc(sizeof (*search), KM_SLEEP); |
| search->ms_weight = UINT64_MAX; |
| search->ms_start = 0; |
| /* |
| * At the end of the metaslab tree are the already-active metaslabs, |
| * first the primaries, then the secondaries. When we resume searching |
| * through the tree, we need to consider ms_allocator and ms_primary so |
| * we start in the location right after where we left off, and don't |
| * accidentally loop forever considering the same metaslabs. |
| */ |
| search->ms_allocator = -1; |
| search->ms_primary = B_TRUE; |
| for (;;) { |
| boolean_t was_active = B_FALSE; |
| |
| mutex_enter(&mg->mg_lock); |
| |
| if (activation_weight == METASLAB_WEIGHT_PRIMARY && |
| mg->mg_primaries[allocator] != NULL) { |
| msp = mg->mg_primaries[allocator]; |
| |
| /* |
| * Even though we don't hold the ms_lock for the |
| * primary metaslab, those fields should not |
| * change while we hold the mg_lock. Thus is is |
| * safe to make assertions on them. |
| */ |
| ASSERT(msp->ms_primary); |
| ASSERT3S(msp->ms_allocator, ==, allocator); |
| ASSERT(msp->ms_loaded); |
| |
| was_active = B_TRUE; |
| } else if (activation_weight == METASLAB_WEIGHT_SECONDARY && |
| mg->mg_secondaries[allocator] != NULL) { |
| msp = mg->mg_secondaries[allocator]; |
| |
| /* |
| * See comment above about the similar assertions |
| * for the primary metaslab. |
| */ |
| ASSERT(!msp->ms_primary); |
| ASSERT3S(msp->ms_allocator, ==, allocator); |
| ASSERT(msp->ms_loaded); |
| |
| was_active = B_TRUE; |
| } else { |
| msp = find_valid_metaslab(mg, activation_weight, dva, d, |
| want_unique, asize, allocator, zal, search, |
| &was_active); |
| } |
| |
| mutex_exit(&mg->mg_lock); |
| if (msp == NULL) { |
| kmem_free(search, sizeof (*search)); |
| return (-1ULL); |
| } |
| mutex_enter(&msp->ms_lock); |
| |
| metaslab_active_mask_verify(msp); |
| |
| /* |
| * This code is disabled out because of issues with |
| * tracepoints in non-gpl kernel modules. |
| */ |
| #if 0 |
| DTRACE_PROBE3(ms__activation__attempt, |
| metaslab_t *, msp, uint64_t, activation_weight, |
| boolean_t, was_active); |
| #endif |
| |
| /* |
| * Ensure that the metaslab we have selected is still |
| * capable of handling our request. It's possible that |
| * another thread may have changed the weight while we |
| * were blocked on the metaslab lock. We check the |
| * active status first to see if we need to reselect |
| * a new metaslab. |
| */ |
| if (was_active && !(msp->ms_weight & METASLAB_ACTIVE_MASK)) { |
| ASSERT3S(msp->ms_allocator, ==, -1); |
| mutex_exit(&msp->ms_lock); |
| continue; |
| } |
| |
| /* |
| * If the metaslab was activated for another allocator |
| * while we were waiting in the ms_lock above, or it's |
| * a primary and we're seeking a secondary (or vice versa), |
| * we go back and select a new metaslab. |
| */ |
| if (!was_active && (msp->ms_weight & METASLAB_ACTIVE_MASK) && |
| (msp->ms_allocator != -1) && |
| (msp->ms_allocator != allocator || ((activation_weight == |
| METASLAB_WEIGHT_PRIMARY) != msp->ms_primary))) { |
| ASSERT(msp->ms_loaded); |
| ASSERT((msp->ms_weight & METASLAB_WEIGHT_CLAIM) || |
| msp->ms_allocator != -1); |
| mutex_exit(&msp->ms_lock); |
| continue; |
| } |
| |
| /* |
| * This metaslab was used for claiming regions allocated |
| * by the ZIL during pool import. Once these regions are |
| * claimed we don't need to keep the CLAIM bit set |
| * anymore. Passivate this metaslab to zero its activation |
| * mask. |
| */ |
| if (msp->ms_weight & METASLAB_WEIGHT_CLAIM && |
| activation_weight != METASLAB_WEIGHT_CLAIM) { |
| ASSERT(msp->ms_loaded); |
| ASSERT3S(msp->ms_allocator, ==, -1); |
| metaslab_passivate(msp, msp->ms_weight & |
| ~METASLAB_WEIGHT_CLAIM); |
| mutex_exit(&msp->ms_lock); |
| continue; |
| } |
| |
| msp->ms_selected_txg = txg; |
| |
| int activation_error = |
| metaslab_activate(msp, allocator, activation_weight); |
| metaslab_active_mask_verify(msp); |
| |
| /* |
| * If the metaslab was activated by another thread for |
| * another allocator or activation_weight (EBUSY), or it |
| * failed because another metaslab was assigned as primary |
| * for this allocator (EEXIST) we continue using this |
| * metaslab for our allocation, rather than going on to a |
| * worse metaslab (we waited for that metaslab to be loaded |
| * after all). |
| * |
| * If the activation failed due to an I/O error or ENOSPC we |
| * skip to the next metaslab. |
| */ |
| boolean_t activated; |
| if (activation_error == 0) { |
| activated = B_TRUE; |
| } else if (activation_error == EBUSY || |
| activation_error == EEXIST) { |
| activated = B_FALSE; |
| } else { |
| mutex_exit(&msp->ms_lock); |
| continue; |
| } |
| ASSERT(msp->ms_loaded); |
| |
| /* |
| * Now that we have the lock, recheck to see if we should |
| * continue to use this metaslab for this allocation. The |
| * the metaslab is now loaded so metaslab_should_allocate() |
| * can accurately determine if the allocation attempt should |
| * proceed. |
| */ |
| if (!metaslab_should_allocate(msp, asize)) { |
| /* Passivate this metaslab and select a new one. */ |
| metaslab_trace_add(zal, mg, msp, asize, d, |
| TRACE_TOO_SMALL, allocator); |
| goto next; |
| } |
| |
| /* |
| * If this metaslab is currently condensing then pick again |
| * as we can't manipulate this metaslab until it's committed |
| * to disk. If this metaslab is being initialized, we shouldn't |
| * allocate from it since the allocated region might be |
| * overwritten after allocation. |
| */ |
| if (msp->ms_condensing) { |
| metaslab_trace_add(zal, mg, msp, asize, d, |
| TRACE_CONDENSING, allocator); |
| if (activated) { |
| metaslab_passivate(msp, msp->ms_weight & |
| ~METASLAB_ACTIVE_MASK); |
| } |
| mutex_exit(&msp->ms_lock); |
| continue; |
| } else if (msp->ms_disabled > 0) { |
| metaslab_trace_add(zal, mg, msp, asize, d, |
| TRACE_DISABLED, allocator); |
| if (activated) { |
| metaslab_passivate(msp, msp->ms_weight & |
| ~METASLAB_ACTIVE_MASK); |
| } |
| mutex_exit(&msp->ms_lock); |
| continue; |
| } |
| |
| offset = metaslab_block_alloc(msp, asize, txg); |
| metaslab_trace_add(zal, mg, msp, asize, d, offset, allocator); |
| |
| if (offset != -1ULL) { |
| /* Proactively passivate the metaslab, if needed */ |
| if (activated) |
| metaslab_segment_may_passivate(msp); |
| break; |
| } |
| next: |
| ASSERT(msp->ms_loaded); |
| |
| /* |
| * This code is disabled out because of issues with |
| * tracepoints in non-gpl kernel modules. |
| */ |
| #if 0 |
| DTRACE_PROBE2(ms__alloc__failure, metaslab_t *, msp, |
| uint64_t, asize); |
| #endif |
| |
| /* |
| * We were unable to allocate from this metaslab so determine |
| * a new weight for this metaslab. Now that we have loaded |
| * the metaslab we can provide a better hint to the metaslab |
| * selector. |
| * |
| * For space-based metaslabs, we use the maximum block size. |
| * This information is only available when the metaslab |
| * is loaded and is more accurate than the generic free |
| * space weight that was calculated by metaslab_weight(). |
| * This information allows us to quickly compare the maximum |
| * available allocation in the metaslab to the allocation |
| * size being requested. |
| * |
| * For segment-based metaslabs, determine the new weight |
| * based on the highest bucket in the range tree. We |
| * explicitly use the loaded segment weight (i.e. the range |
| * tree histogram) since it contains the space that is |
| * currently available for allocation and is accurate |
| * even within a sync pass. |
| */ |
| uint64_t weight; |
| if (WEIGHT_IS_SPACEBASED(msp->ms_weight)) { |
| weight = metaslab_block_maxsize(msp); |
| WEIGHT_SET_SPACEBASED(weight); |
| } else { |
| weight = metaslab_weight_from_range_tree(msp); |
| } |
| |
| if (activated) { |
| metaslab_passivate(msp, weight); |
| } else { |
| /* |
| * For the case where we use the metaslab that is |
| * active for another allocator we want to make |
| * sure that we retain the activation mask. |
| * |
| * Note that we could attempt to use something like |
| * metaslab_recalculate_weight_and_sort() that |
| * retains the activation mask here. That function |
| * uses metaslab_weight() to set the weight though |
| * which is not as accurate as the calculations |
| * above. |
| */ |
| weight |= msp->ms_weight & METASLAB_ACTIVE_MASK; |
| metaslab_group_sort(mg, msp, weight); |
| } |
| metaslab_active_mask_verify(msp); |
| |
| /* |
| * We have just failed an allocation attempt, check |
| * that metaslab_should_allocate() agrees. Otherwise, |
| * we may end up in an infinite loop retrying the same |
| * metaslab. |
| */ |
| ASSERT(!metaslab_should_allocate(msp, asize)); |
| |
| mutex_exit(&msp->ms_lock); |
| } |
| mutex_exit(&msp->ms_lock); |
| kmem_free(search, sizeof (*search)); |
| return (offset); |
| } |
| |
| static uint64_t |
| metaslab_group_alloc(metaslab_group_t *mg, zio_alloc_list_t *zal, |
| uint64_t asize, uint64_t txg, boolean_t want_unique, dva_t *dva, |
| int d, int allocator) |
| { |
| uint64_t offset; |
| ASSERT(mg->mg_initialized); |
| |
| offset = metaslab_group_alloc_normal(mg, zal, asize, txg, want_unique, |
| dva, d, allocator); |
| |
| mutex_enter(&mg->mg_lock); |
| if (offset == -1ULL) { |
| mg->mg_failed_allocations++; |
| metaslab_trace_add(zal, mg, NULL, asize, d, |
| TRACE_GROUP_FAILURE, allocator); |
| if (asize == SPA_GANGBLOCKSIZE) { |
| /* |
| * This metaslab group was unable to allocate |
| * the minimum gang block size so it must be out of |
| * space. We must notify the allocation throttle |
| * to start skipping allocation attempts to this |
| * metaslab group until more space becomes available. |
| * Note: this failure cannot be caused by the |
| * allocation throttle since the allocation throttle |
| * is only responsible for skipping devices and |
| * not failing block allocations. |
| */ |
| mg->mg_no_free_space = B_TRUE; |
| } |
| } |
| mg->mg_allocations++; |
| mutex_exit(&mg->mg_lock); |
| return (offset); |
| } |
| |
| /* |
| * Allocate a block for the specified i/o. |
| */ |
| int |
| metaslab_alloc_dva(spa_t *spa, metaslab_class_t *mc, uint64_t psize, |
| dva_t *dva, int d, dva_t *hintdva, uint64_t txg, int flags, |
| zio_alloc_list_t *zal, int allocator) |
| { |
| metaslab_group_t *mg, *fast_mg, *rotor; |
| vdev_t *vd; |
| boolean_t try_hard = B_FALSE; |
| |
| ASSERT(!DVA_IS_VALID(&dva[d])); |
| |
| /* |
| * For testing, make some blocks above a certain size be gang blocks. |
| * This will result in more split blocks when using device removal, |
| * and a large number of split blocks coupled with ztest-induced |
| * damage can result in extremely long reconstruction times. This |
| * will also test spilling from special to normal. |
| */ |
| if (psize >= metaslab_force_ganging && (spa_get_random(100) < 3)) { |
| metaslab_trace_add(zal, NULL, NULL, psize, d, TRACE_FORCE_GANG, |
| allocator); |
| return (SET_ERROR(ENOSPC)); |
| } |
| |
| /* |
| * Start at the rotor and loop through all mgs until we find something. |
| * Note that there's no locking on mc_rotor or mc_aliquot because |
| * nothing actually breaks if we miss a few updates -- we just won't |
| * allocate quite as evenly. It all balances out over time. |
| * |
| * If we are doing ditto or log blocks, try to spread them across |
| * consecutive vdevs. If we're forced to reuse a vdev before we've |
| * allocated all of our ditto blocks, then try and spread them out on |
| * that vdev as much as possible. If it turns out to not be possible, |
| * gradually lower our standards until anything becomes acceptable. |
| * Also, allocating on consecutive vdevs (as opposed to random vdevs) |
| * gives us hope of containing our fault domains to something we're |
| * able to reason about. Otherwise, any two top-level vdev failures |
| * will guarantee the loss of data. With consecutive allocation, |
| * only two adjacent top-level vdev failures will result in data loss. |
| * |
| * If we are doing gang blocks (hintdva is non-NULL), try to keep |
| * ourselves on the same vdev as our gang block header. That |
| * way, we can hope for locality in vdev_cache, plus it makes our |
| * fault domains something tractable. |
| */ |
| if (hintdva) { |
| vd = vdev_lookup_top(spa, DVA_GET_VDEV(&hintdva[d])); |
| |
| /* |
| * It's possible the vdev we're using as the hint no |
| * longer exists or its mg has been closed (e.g. by |
| * device removal). Consult the rotor when |
| * all else fails. |
| */ |
| if (vd != NULL && vd->vdev_mg != NULL) { |
| mg = vd->vdev_mg; |
| |
| if (flags & METASLAB_HINTBP_AVOID && |
| mg->mg_next != NULL) |
| mg = mg->mg_next; |
| } else { |
| mg = mc->mc_rotor; |
| } |
| } else if (d != 0) { |
| vd = vdev_lookup_top(spa, DVA_GET_VDEV(&dva[d - 1])); |
| mg = vd->vdev_mg->mg_next; |
| } else if (flags & METASLAB_FASTWRITE) { |
| mg = fast_mg = mc->mc_rotor; |
| |
| do { |
| if (fast_mg->mg_vd->vdev_pending_fastwrite < |
| mg->mg_vd->vdev_pending_fastwrite) |
| mg = fast_mg; |
| } while ((fast_mg = fast_mg->mg_next) != mc->mc_rotor); |
| |
| } else { |
| ASSERT(mc->mc_rotor != NULL); |
| mg = mc->mc_rotor; |
| } |
| |
| /* |
| * If the hint put us into the wrong metaslab class, or into a |
| * metaslab group that has been passivated, just follow the rotor. |
| */ |
| if (mg->mg_class != mc || mg->mg_activation_count <= 0) |
| mg = mc->mc_rotor; |
| |
| rotor = mg; |
| top: |
| do { |
| boolean_t allocatable; |
| |
| ASSERT(mg->mg_activation_count == 1); |
| vd = mg->mg_vd; |
| |
| /* |
| * Don't allocate from faulted devices. |
| */ |
| if (try_hard) { |
| spa_config_enter(spa, SCL_ZIO, FTAG, RW_READER); |
| allocatable = vdev_allocatable(vd); |
| spa_config_exit(spa, SCL_ZIO, FTAG); |
| } else { |
| allocatable = vdev_allocatable(vd); |
| } |
| |
| /* |
| * Determine if the selected metaslab group is eligible |
| * for allocations. If we're ganging then don't allow |
| * this metaslab group to skip allocations since that would |
| * inadvertently return ENOSPC and suspend the pool |
| * even though space is still available. |
| */ |
| if (allocatable && !GANG_ALLOCATION(flags) && !try_hard) { |
| allocatable = metaslab_group_allocatable(mg, rotor, |
| psize, allocator, d); |
| } |
| |
| if (!allocatable) { |
| metaslab_trace_add(zal, mg, NULL, psize, d, |
| TRACE_NOT_ALLOCATABLE, allocator); |
| goto next; |
| } |
| |
| ASSERT(mg->mg_initialized); |
| |
| /* |
| * Avoid writing single-copy data to a failing, |
| * non-redundant vdev, unless we've already tried all |
| * other vdevs. |
| */ |
| if ((vd->vdev_stat.vs_write_errors > 0 || |
| vd->vdev_state < VDEV_STATE_HEALTHY) && |
| d == 0 && !try_hard && vd->vdev_children == 0) { |
| metaslab_trace_add(zal, mg, NULL, psize, d, |
| TRACE_VDEV_ERROR, allocator); |
| goto next; |
| } |
| |
| ASSERT(mg->mg_class == mc); |
| |
| uint64_t asize = vdev_psize_to_asize(vd, psize); |
| ASSERT(P2PHASE(asize, 1ULL << vd->vdev_ashift) == 0); |
| |
| /* |
| * If we don't need to try hard, then require that the |
| * block be on an different metaslab from any other DVAs |
| * in this BP (unique=true). If we are trying hard, then |
| * allow any metaslab to be used (unique=false). |
| */ |
| uint64_t offset = metaslab_group_alloc(mg, zal, asize, txg, |
| !try_hard, dva, d, allocator); |
| |
| if (offset != -1ULL) { |
| /* |
| * If we've just selected this metaslab group, |
| * figure out whether the corresponding vdev is |
| * over- or under-used relative to the pool, |
| * and set an allocation bias to even it out. |
| * |
| * Bias is also used to compensate for unequally |
| * sized vdevs so that space is allocated fairly. |
| */ |
| if (mc->mc_aliquot == 0 && metaslab_bias_enabled) { |
| vdev_stat_t *vs = &vd->vdev_stat; |
| int64_t vs_free = vs->vs_space - vs->vs_alloc; |
| int64_t mc_free = mc->mc_space - mc->mc_alloc; |
| int64_t ratio; |
| |
| /* |
| * Calculate how much more or less we should |
| * try to allocate from this device during |
| * this iteration around the rotor. |
| * |
| * This basically introduces a zero-centered |
| * bias towards the devices with the most |
| * free space, while compensating for vdev |
| * size differences. |
| * |
| * Examples: |
| * vdev V1 = 16M/128M |
| * vdev V2 = 16M/128M |
| * ratio(V1) = 100% ratio(V2) = 100% |
| * |
| * vdev V1 = 16M/128M |
| * vdev V2 = 64M/128M |
| * ratio(V1) = 127% ratio(V2) = 72% |
| * |
| * vdev V1 = 16M/128M |
| * vdev V2 = 64M/512M |
| * ratio(V1) = 40% ratio(V2) = 160% |
| */ |
| ratio = (vs_free * mc->mc_alloc_groups * 100) / |
| (mc_free + 1); |
| mg->mg_bias = ((ratio - 100) * |
| (int64_t)mg->mg_aliquot) / 100; |
| } else if (!metaslab_bias_enabled) { |
| mg->mg_bias = 0; |
| } |
| |
| if ((flags & METASLAB_FASTWRITE) || |
| atomic_add_64_nv(&mc->mc_aliquot, asize) >= |
| mg->mg_aliquot + mg->mg_bias) { |
| mc->mc_rotor = mg->mg_next; |
| mc->mc_aliquot = 0; |
| } |
| |
| DVA_SET_VDEV(&dva[d], vd->vdev_id); |
| DVA_SET_OFFSET(&dva[d], offset); |
| DVA_SET_GANG(&dva[d], |
| ((flags & METASLAB_GANG_HEADER) ? 1 : 0)); |
| DVA_SET_ASIZE(&dva[d], asize); |
| |
| if (flags & METASLAB_FASTWRITE) { |
| atomic_add_64(&vd->vdev_pending_fastwrite, |
| psize); |
| } |
| |
| return (0); |
| } |
| next: |
| mc->mc_rotor = mg->mg_next; |
| mc->mc_aliquot = 0; |
| } while ((mg = mg->mg_next) != rotor); |
| |
| /* |
| * If we haven't tried hard, do so now. |
| */ |
| if (!try_hard) { |
| try_hard = B_TRUE; |
| goto top; |
| } |
| |
| bzero(&dva[d], sizeof (dva_t)); |
| |
| metaslab_trace_add(zal, rotor, NULL, psize, d, TRACE_ENOSPC, allocator); |
| return (SET_ERROR(ENOSPC)); |
| } |
| |
| void |
| metaslab_free_concrete(vdev_t *vd, uint64_t offset, uint64_t asize, |
| boolean_t checkpoint) |
| { |
| metaslab_t *msp; |
| spa_t *spa = vd->vdev_spa; |
| |
| ASSERT(vdev_is_concrete(vd)); |
| ASSERT3U(spa_config_held(spa, SCL_ALL, RW_READER), !=, 0); |
| ASSERT3U(offset >> vd->vdev_ms_shift, <, vd->vdev_ms_count); |
| |
| msp = vd->vdev_ms[offset >> vd->vdev_ms_shift]; |
| |
| VERIFY(!msp->ms_condensing); |
| VERIFY3U(offset, >=, msp->ms_start); |
| VERIFY3U(offset + asize, <=, msp->ms_start + msp->ms_size); |
| VERIFY0(P2PHASE(offset, 1ULL << vd->vdev_ashift)); |
| VERIFY0(P2PHASE(asize, 1ULL << vd->vdev_ashift)); |
| |
| metaslab_check_free_impl(vd, offset, asize); |
| |
| mutex_enter(&msp->ms_lock); |
| if (range_tree_is_empty(msp->ms_freeing) && |
| range_tree_is_empty(msp->ms_checkpointing)) { |
| vdev_dirty(vd, VDD_METASLAB, msp, spa_syncing_txg(spa)); |
| } |
| |
| if (checkpoint) { |
| ASSERT(spa_has_checkpoint(spa)); |
| range_tree_add(msp->ms_checkpointing, offset, asize); |
| } else { |
| range_tree_add(msp->ms_freeing, offset, asize); |
| } |
| mutex_exit(&msp->ms_lock); |
| } |
| |
| /* ARGSUSED */ |
| void |
| metaslab_free_impl_cb(uint64_t inner_offset, vdev_t *vd, uint64_t offset, |
| uint64_t size, void *arg) |
| { |
| boolean_t *checkpoint = arg; |
| |
| ASSERT3P(checkpoint, !=, NULL); |
| |
| if (vd->vdev_ops->vdev_op_remap != NULL) |
| vdev_indirect_mark_obsolete(vd, offset, size); |
| else |
| metaslab_free_impl(vd, offset, size, *checkpoint); |
| } |
| |
| static void |
| metaslab_free_impl(vdev_t *vd, uint64_t offset, uint64_t size, |
| boolean_t checkpoint) |
| { |
| spa_t *spa = vd->vdev_spa; |
| |
| ASSERT3U(spa_config_held(spa, SCL_ALL, RW_READER), !=, 0); |
| |
| if (spa_syncing_txg(spa) > spa_freeze_txg(spa)) |
| return; |
| |
| if (spa->spa_vdev_removal != NULL && |
| spa->spa_vdev_removal->svr_vdev_id == vd->vdev_id && |
| vdev_is_concrete(vd)) { |
| /* |
| * Note: we check if the vdev is concrete because when |
| * we complete the removal, we first change the vdev to be |
| * an indirect vdev (in open context), and then (in syncing |
| * context) clear spa_vdev_removal. |
| */ |
| free_from_removing_vdev(vd, offset, size); |
| } else if (vd->vdev_ops->vdev_op_remap != NULL) { |
| vdev_indirect_mark_obsolete(vd, offset, size); |
| vd->vdev_ops->vdev_op_remap(vd, offset, size, |
| metaslab_free_impl_cb, &checkpoint); |
| } else { |
| metaslab_free_concrete(vd, offset, size, checkpoint); |
| } |
| } |
| |
| typedef struct remap_blkptr_cb_arg { |
| blkptr_t *rbca_bp; |
| spa_remap_cb_t rbca_cb; |
| vdev_t *rbca_remap_vd; |
| uint64_t rbca_remap_offset; |
| void *rbca_cb_arg; |
| } remap_blkptr_cb_arg_t; |
| |
| void |
| remap_blkptr_cb(uint64_t inner_offset, vdev_t *vd, uint64_t offset, |
| uint64_t size, void *arg) |
| { |
| remap_blkptr_cb_arg_t *rbca = arg; |
| blkptr_t *bp = rbca->rbca_bp; |
| |
| /* We can not remap split blocks. */ |
| if (size != DVA_GET_ASIZE(&bp->blk_dva[0])) |
| return; |
| ASSERT0(inner_offset); |
| |
| if (rbca->rbca_cb != NULL) { |
| /* |
| * At this point we know that we are not handling split |
| * blocks and we invoke the callback on the previous |
| * vdev which must be indirect. |
| */ |
| ASSERT3P(rbca->rbca_remap_vd->vdev_ops, ==, &vdev_indirect_ops); |
| |
| rbca->rbca_cb(rbca->rbca_remap_vd->vdev_id, |
| rbca->rbca_remap_offset, size, rbca->rbca_cb_arg); |
| |
| /* set up remap_blkptr_cb_arg for the next call */ |
| rbca->rbca_remap_vd = vd; |
| rbca->rbca_remap_offset = offset; |
| } |
| |
| /* |
| * The phys birth time is that of dva[0]. This ensures that we know |
| * when each dva was written, so that resilver can determine which |
| * blocks need to be scrubbed (i.e. those written during the time |
| * the vdev was offline). It also ensures that the key used in |
| * the ARC hash table is unique (i.e. dva[0] + phys_birth). If |
| * we didn't change the phys_birth, a lookup in the ARC for a |
| * remapped BP could find the data that was previously stored at |
| * this vdev + offset. |
| */ |
| vdev_t *oldvd = vdev_lookup_top(vd->vdev_spa, |
| DVA_GET_VDEV(&bp->blk_dva[0])); |
| vdev_indirect_births_t *vib = oldvd->vdev_indirect_births; |
| bp->blk_phys_birth = vdev_indirect_births_physbirth(vib, |
| DVA_GET_OFFSET(&bp->blk_dva[0]), DVA_GET_ASIZE(&bp->blk_dva[0])); |
| |
| DVA_SET_VDEV(&bp->blk_dva[0], vd->vdev_id); |
| DVA_SET_OFFSET(&bp->blk_dva[0], offset); |
| } |
| |
| /* |
| * If the block pointer contains any indirect DVAs, modify them to refer to |
| * concrete DVAs. Note that this will sometimes not be possible, leaving |
| * the indirect DVA in place. This happens if the indirect DVA spans multiple |
| * segments in the mapping (i.e. it is a "split block"). |
| * |
| * If the BP was remapped, calls the callback on the original dva (note the |
| * callback can be called multiple times if the original indirect DVA refers |
| * to another indirect DVA, etc). |
| * |
| * Returns TRUE if the BP was remapped. |
| */ |
| boolean_t |
| spa_remap_blkptr(spa_t *spa, blkptr_t *bp, spa_remap_cb_t callback, void *arg) |
| { |
| remap_blkptr_cb_arg_t rbca; |
| |
| if (!zfs_remap_blkptr_enable) |
| return (B_FALSE); |
| |
| if (!spa_feature_is_enabled(spa, SPA_FEATURE_OBSOLETE_COUNTS)) |
| return (B_FALSE); |
| |
| /* |
| * Dedup BP's can not be remapped, because ddt_phys_select() depends |
| * on DVA[0] being the same in the BP as in the DDT (dedup table). |
| */ |
| if (BP_GET_DEDUP(bp)) |
| return (B_FALSE); |
| |
| /* |
| * Gang blocks can not be remapped, because |
| * zio_checksum_gang_verifier() depends on the DVA[0] that's in |
| * the BP used to read the gang block header (GBH) being the same |
| * as the DVA[0] that we allocated for the GBH. |
| */ |
| if (BP_IS_GANG(bp)) |
| return (B_FALSE); |
| |
| /* |
| * Embedded BP's have no DVA to remap. |
| */ |
| if (BP_GET_NDVAS(bp) < 1) |
| return (B_FALSE); |
| |
| /* |
| * Note: we only remap dva[0]. If we remapped other dvas, we |
| * would no longer know what their phys birth txg is. |
| */ |
| dva_t *dva = &bp->blk_dva[0]; |
| |
| uint64_t offset = DVA_GET_OFFSET(dva); |
| uint64_t size = DVA_GET_ASIZE(dva); |
| vdev_t *vd = vdev_lookup_top(spa, DVA_GET_VDEV(dva)); |
| |
| if (vd->vdev_ops->vdev_op_remap == NULL) |
| return (B_FALSE); |
| |
| rbca.rbca_bp = bp; |
| rbca.rbca_cb = callback; |
| rbca.rbca_remap_vd = vd; |
| rbca.rbca_remap_offset = offset; |
| rbca.rbca_cb_arg = arg; |
| |
| /* |
| * remap_blkptr_cb() will be called in order for each level of |
| * indirection, until a concrete vdev is reached or a split block is |
| * encountered. old_vd and old_offset are updated within the callback |
| * as we go from the one indirect vdev to the next one (either concrete |
| * or indirect again) in that order. |
| */ |
| vd->vdev_ops->vdev_op_remap(vd, offset, size, remap_blkptr_cb, &rbca); |
| |
| /* Check if the DVA wasn't remapped because it is a split block */ |
| if (DVA_GET_VDEV(&rbca.rbca_bp->blk_dva[0]) == vd->vdev_id) |
| return (B_FALSE); |
| |
| return (B_TRUE); |
| } |
| |
| /* |
| * Undo the allocation of a DVA which happened in the given transaction group. |
| */ |
| void |
| metaslab_unalloc_dva(spa_t *spa, const dva_t *dva, uint64_t txg) |
| { |
| metaslab_t *msp; |
| vdev_t *vd; |
| uint64_t vdev = DVA_GET_VDEV(dva); |
| uint64_t offset = DVA_GET_OFFSET(dva); |
| uint64_t size = DVA_GET_ASIZE(dva); |
| |
| ASSERT(DVA_IS_VALID(dva)); |
| ASSERT3U(spa_config_held(spa, SCL_ALL, RW_READER), !=, 0); |
| |
| if (txg > spa_freeze_txg(spa)) |
| return; |
| |
| if ((vd = vdev_lookup_top(spa, vdev)) == NULL || !DVA_IS_VALID(dva) || |
| (offset >> vd->vdev_ms_shift) >= vd->vdev_ms_count) { |
| zfs_panic_recover("metaslab_free_dva(): bad DVA %llu:%llu:%llu", |
| (u_longlong_t)vdev, (u_longlong_t)offset, |
| (u_longlong_t)size); |
| return; |
| } |
| |
| ASSERT(!vd->vdev_removing); |
| ASSERT(vdev_is_concrete(vd)); |
| ASSERT0(vd->vdev_indirect_config.vic_mapping_object); |
| ASSERT3P(vd->vdev_indirect_mapping, ==, NULL); |
| |
| if (DVA_GET_GANG(dva)) |
| size = vdev_psize_to_asize(vd, SPA_GANGBLOCKSIZE); |
| |
| msp = vd->vdev_ms[offset >> vd->vdev_ms_shift]; |
| |
| mutex_enter(&msp->ms_lock); |
| range_tree_remove(msp->ms_allocating[txg & TXG_MASK], |
| offset, size); |
| |
| VERIFY(!msp->ms_condensing); |
| VERIFY3U(offset, >=, msp->ms_start); |
| VERIFY3U(offset + size, <=, msp->ms_start + msp->ms_size); |
| VERIFY3U(range_tree_space(msp->ms_allocatable) + size, <=, |
| msp->ms_size); |
| VERIFY0(P2PHASE(offset, 1ULL << vd->vdev_ashift)); |
| VERIFY0(P2PHASE(size, 1ULL << vd->vdev_ashift)); |
| range_tree_add(msp->ms_allocatable, offset, size); |
| mutex_exit(&msp->ms_lock); |
| } |
| |
| /* |
| * Free the block represented by the given DVA. |
| */ |
| void |
| metaslab_free_dva(spa_t *spa, const dva_t *dva, boolean_t checkpoint) |
| { |
| uint64_t vdev = DVA_GET_VDEV(dva); |
| uint64_t offset = DVA_GET_OFFSET(dva); |
| uint64_t size = DVA_GET_ASIZE(dva); |
| vdev_t *vd = vdev_lookup_top(spa, vdev); |
| |
| ASSERT(DVA_IS_VALID(dva)); |
| ASSERT3U(spa_config_held(spa, SCL_ALL, RW_READER), !=, 0); |
| |
| if (DVA_GET_GANG(dva)) { |
| size = vdev_psize_to_asize(vd, SPA_GANGBLOCKSIZE); |
| } |
| |
| metaslab_free_impl(vd, offset, size, checkpoint); |
| } |
| |
| /* |
| * Reserve some allocation slots. The reservation system must be called |
| * before we call into the allocator. If there aren't any available slots |
| * then the I/O will be throttled until an I/O completes and its slots are |
| * freed up. The function returns true if it was successful in placing |
| * the reservation. |
| */ |
| boolean_t |
| metaslab_class_throttle_reserve(metaslab_class_t *mc, int slots, int allocator, |
| zio_t *zio, int flags) |
| { |
| uint64_t available_slots = 0; |
| boolean_t slot_reserved = B_FALSE; |
| uint64_t max = mc->mc_alloc_max_slots[allocator]; |
| |
| ASSERT(mc->mc_alloc_throttle_enabled); |
| mutex_enter(&mc->mc_lock); |
| |
| uint64_t reserved_slots = |
| zfs_refcount_count(&mc->mc_alloc_slots[allocator]); |
| if (reserved_slots < max) |
| available_slots = max - reserved_slots; |
| |
| if (slots <= available_slots || GANG_ALLOCATION(flags) || |
| flags & METASLAB_MUST_RESERVE) { |
| /* |
| * We reserve the slots individually so that we can unreserve |
| * them individually when an I/O completes. |
| */ |
| for (int d = 0; d < slots; d++) { |
| reserved_slots = |
| zfs_refcount_add(&mc->mc_alloc_slots[allocator], |
| zio); |
| } |
| zio->io_flags |= ZIO_FLAG_IO_ALLOCATING; |
| slot_reserved = B_TRUE; |
| } |
| |
| mutex_exit(&mc->mc_lock); |
| return (slot_reserved); |
| } |
| |
| void |
| metaslab_class_throttle_unreserve(metaslab_class_t *mc, int slots, |
| int allocator, zio_t *zio) |
| { |
| ASSERT(mc->mc_alloc_throttle_enabled); |
| mutex_enter(&mc->mc_lock); |
| for (int d = 0; d < slots; d++) { |
| (void) zfs_refcount_remove(&mc->mc_alloc_slots[allocator], |
| zio); |
| } |
| mutex_exit(&mc->mc_lock); |
| } |
| |
| static int |
| metaslab_claim_concrete(vdev_t *vd, uint64_t offset, uint64_t size, |
| uint64_t txg) |
| { |
| metaslab_t *msp; |
| spa_t *spa = vd->vdev_spa; |
| int error = 0; |
| |
| if (offset >> vd->vdev_ms_shift >= vd->vdev_ms_count) |
| return (SET_ERROR(ENXIO)); |
| |
| ASSERT3P(vd->vdev_ms, !=, NULL); |
| msp = vd->vdev_ms[offset >> vd->vdev_ms_shift]; |
| |
| mutex_enter(&msp->ms_lock); |
| |
| if ((txg != 0 && spa_writeable(spa)) || !msp->ms_loaded) { |
| error = metaslab_activate(msp, 0, METASLAB_WEIGHT_CLAIM); |
| if (error == EBUSY) { |
| ASSERT(msp->ms_loaded); |
| ASSERT(msp->ms_weight & METASLAB_ACTIVE_MASK); |
| error = 0; |
| } |
| } |
| |
| if (error == 0 && |
| !range_tree_contains(msp->ms_allocatable, offset, size)) |
| error = SET_ERROR(ENOENT); |
| |
| if (error || txg == 0) { /* txg == 0 indicates dry run */ |
| mutex_exit(&msp->ms_lock); |
| return (error); |
| } |
| |
| VERIFY(!msp->ms_condensing); |
| VERIFY0(P2PHASE(offset, 1ULL << vd->vdev_ashift)); |
| VERIFY0(P2PHASE(size, 1ULL << vd->vdev_ashift)); |
| VERIFY3U(range_tree_space(msp->ms_allocatable) - size, <=, |
| msp->ms_size); |
| range_tree_remove(msp->ms_allocatable, offset, size); |
| range_tree_clear(msp->ms_trim, offset, size); |
| |
| if (spa_writeable(spa)) { /* don't dirty if we're zdb(1M) */ |
| if (range_tree_is_empty(msp->ms_allocating[txg & TXG_MASK])) |
| vdev_dirty(vd, VDD_METASLAB, msp, txg); |
| range_tree_add(msp->ms_allocating[txg & TXG_MASK], |
| offset, size); |
| } |
| |
| mutex_exit(&msp->ms_lock); |
| |
| return (0); |
| } |
| |
| typedef struct metaslab_claim_cb_arg_t { |
| uint64_t mcca_txg; |
| int mcca_error; |
| } metaslab_claim_cb_arg_t; |
| |
| /* ARGSUSED */ |
| static void |
| metaslab_claim_impl_cb(uint64_t inner_offset, vdev_t *vd, uint64_t offset, |
| uint64_t size, void *arg) |
| { |
| metaslab_claim_cb_arg_t *mcca_arg = arg; |
| |
| if (mcca_arg->mcca_error == 0) { |
| mcca_arg->mcca_error = metaslab_claim_concrete(vd, offset, |
| size, mcca_arg->mcca_txg); |
| } |
| } |
| |
| int |
| metaslab_claim_impl(vdev_t *vd, uint64_t offset, uint64_t size, uint64_t txg) |
| { |
| if (vd->vdev_ops->vdev_op_remap != NULL) { |
| metaslab_claim_cb_arg_t arg; |
| |
| /* |
| * Only zdb(1M) can claim on indirect vdevs. This is used |
| * to detect leaks of mapped space (that are not accounted |
| * for in the obsolete counts, spacemap, or bpobj). |
| */ |
| ASSERT(!spa_writeable(vd->vdev_spa)); |
| arg.mcca_error = 0; |
| arg.mcca_txg = txg; |
| |
| vd->vdev_ops->vdev_op_remap(vd, offset, size, |
| metaslab_claim_impl_cb, &arg); |
| |
| if (arg.mcca_error == 0) { |
| arg.mcca_error = metaslab_claim_concrete(vd, |
| offset, size, txg); |
| } |
| return (arg.mcca_error); |
| } else { |
| return (metaslab_claim_concrete(vd, offset, size, txg)); |
| } |
| } |
| |
| /* |
| * Intent log support: upon opening the pool after a crash, notify the SPA |
| * of blocks that the intent log has allocated for immediate write, but |
| * which are still considered free by the SPA because the last transaction |
| * group didn't commit yet. |
| */ |
| static int |
| metaslab_claim_dva(spa_t *spa, const dva_t *dva, uint64_t txg) |
| { |
| uint64_t vdev = DVA_GET_VDEV(dva); |
| uint64_t offset = DVA_GET_OFFSET(dva); |
| uint64_t size = DVA_GET_ASIZE(dva); |
| vdev_t *vd; |
| |
| if ((vd = vdev_lookup_top(spa, vdev)) == NULL) { |
| return (SET_ERROR(ENXIO)); |
| } |
| |
| ASSERT(DVA_IS_VALID(dva)); |
| |
| if (DVA_GET_GANG(dva)) |
| size = vdev_psize_to_asize(vd, SPA_GANGBLOCKSIZE); |
| |
| return (metaslab_claim_impl(vd, offset, size, txg)); |
| } |
| |
| int |
| metaslab_alloc(spa_t *spa, metaslab_class_t *mc, uint64_t psize, blkptr_t *bp, |
| int ndvas, uint64_t txg, blkptr_t *hintbp, int flags, |
| zio_alloc_list_t *zal, zio_t *zio, int allocator) |
| { |
| dva_t *dva = bp->blk_dva; |
| dva_t *hintdva = (hintbp != NULL) ? hintbp->blk_dva : NULL; |
| int error = 0; |
| |
| ASSERT(bp->blk_birth == 0); |
| ASSERT(BP_PHYSICAL_BIRTH(bp) == 0); |
| |
| spa_config_enter(spa, SCL_ALLOC, FTAG, RW_READER); |
| |
| if (mc->mc_rotor == NULL) { /* no vdevs in this class */ |
| spa_config_exit(spa, SCL_ALLOC, FTAG); |
| return (SET_ERROR(ENOSPC)); |
| } |
| |
| ASSERT(ndvas > 0 && ndvas <= spa_max_replication(spa)); |
| ASSERT(BP_GET_NDVAS(bp) == 0); |
| ASSERT(hintbp == NULL || ndvas <= BP_GET_NDVAS(hintbp)); |
| ASSERT3P(zal, !=, NULL); |
| |
| for (int d = 0; d < ndvas; d++) { |
| error = metaslab_alloc_dva(spa, mc, psize, dva, d, hintdva, |
| txg, flags, zal, allocator); |
| if (error != 0) { |
| for (d--; d >= 0; d--) { |
| metaslab_unalloc_dva(spa, &dva[d], txg); |
| metaslab_group_alloc_decrement(spa, |
| DVA_GET_VDEV(&dva[d]), zio, flags, |
| allocator, B_FALSE); |
| bzero(&dva[d], sizeof (dva_t)); |
| } |
| spa_config_exit(spa, SCL_ALLOC, FTAG); |
| return (error); |
| } else { |
| /* |
| * Update the metaslab group's queue depth |
| * based on the newly allocated dva. |
| */ |
| metaslab_group_alloc_increment(spa, |
| DVA_GET_VDEV(&dva[d]), zio, flags, allocator); |
| } |
| |
| } |
| ASSERT(error == 0); |
| ASSERT(BP_GET_NDVAS(bp) == ndvas); |
| |
| spa_config_exit(spa, SCL_ALLOC, FTAG); |
| |
| BP_SET_BIRTH(bp, txg, 0); |
| |
| return (0); |
| } |
| |
| void |
| metaslab_free(spa_t *spa, const blkptr_t *bp, uint64_t txg, boolean_t now) |
| { |
| const dva_t *dva = bp->blk_dva; |
| int ndvas = BP_GET_NDVAS(bp); |
| |
| ASSERT(!BP_IS_HOLE(bp)); |
| ASSERT(!now || bp->blk_birth >= spa_syncing_txg(spa)); |
| |
| /* |
| * If we have a checkpoint for the pool we need to make sure that |
| * the blocks that we free that are part of the checkpoint won't be |
| * reused until the checkpoint is discarded or we revert to it. |
| * |
| * The checkpoint flag is passed down the metaslab_free code path |
| * and is set whenever we want to add a block to the checkpoint's |
| * accounting. That is, we "checkpoint" blocks that existed at the |
| * time the checkpoint was created and are therefore referenced by |
| * the checkpointed uberblock. |
| * |
| * Note that, we don't checkpoint any blocks if the current |
| * syncing txg <= spa_checkpoint_txg. We want these frees to sync |
| * normally as they will be referenced by the checkpointed uberblock. |
| */ |
| boolean_t checkpoint = B_FALSE; |
| if (bp->blk_birth <= spa->spa_checkpoint_txg && |
| spa_syncing_txg(spa) > spa->spa_checkpoint_txg) { |
| /* |
| * At this point, if the block is part of the checkpoint |
| * there is no way it was created in the current txg. |
| */ |
| ASSERT(!now); |
| ASSERT3U(spa_syncing_txg(spa), ==, txg); |
| checkpoint = B_TRUE; |
| } |
| |
| spa_config_enter(spa, SCL_FREE, FTAG, RW_READER); |
| |
| for (int d = 0; d < ndvas; d++) { |
| if (now) { |
| metaslab_unalloc_dva(spa, &dva[d], txg); |
| } else { |
| ASSERT3U(txg, ==, spa_syncing_txg(spa)); |
| metaslab_free_dva(spa, &dva[d], checkpoint); |
| } |
| } |
| |
| spa_config_exit(spa, SCL_FREE, FTAG); |
| } |
| |
| int |
| metaslab_claim(spa_t *spa, const blkptr_t *bp, uint64_t txg) |
| { |
| const dva_t *dva = bp->blk_dva; |
| int ndvas = BP_GET_NDVAS(bp); |
| int error = 0; |
| |
| ASSERT(!BP_IS_HOLE(bp)); |
| |
| if (txg != 0) { |
| /* |
| * First do a dry run to make sure all DVAs are claimable, |
| * so we don't have to unwind from partial failures below. |
| */ |
| if ((error = metaslab_claim(spa, bp, 0)) != 0) |
| return (error); |
| } |
| |
| spa_config_enter(spa, SCL_ALLOC, FTAG, RW_READER); |
| |
| for (int d = 0; d < ndvas; d++) { |
| error = metaslab_claim_dva(spa, &dva[d], txg); |
| if (error != 0) |
| break; |
| } |
| |
| spa_config_exit(spa, SCL_ALLOC, FTAG); |
| |
| ASSERT(error == 0 || txg == 0); |
| |
| return (error); |
| } |
| |
| void |
| metaslab_fastwrite_mark(spa_t *spa, const blkptr_t *bp) |
| { |
| const dva_t *dva = bp->blk_dva; |
| int ndvas = BP_GET_NDVAS(bp); |
| uint64_t psize = BP_GET_PSIZE(bp); |
| int d; |
| vdev_t *vd; |
| |
| ASSERT(!BP_IS_HOLE(bp)); |
| ASSERT(!BP_IS_EMBEDDED(bp)); |
| ASSERT(psize > 0); |
| |
| spa_config_enter(spa, SCL_VDEV, FTAG, RW_READER); |
| |
| for (d = 0; d < ndvas; d++) { |
| if ((vd = vdev_lookup_top(spa, DVA_GET_VDEV(&dva[d]))) == NULL) |
| continue; |
| atomic_add_64(&vd->vdev_pending_fastwrite, psize); |
| } |
| |
| spa_config_exit(spa, SCL_VDEV, FTAG); |
| } |
| |
| void |
| metaslab_fastwrite_unmark(spa_t *spa, const blkptr_t *bp) |
| { |
| const dva_t *dva = bp->blk_dva; |
| int ndvas = BP_GET_NDVAS(bp); |
| uint64_t psize = BP_GET_PSIZE(bp); |
| int d; |
| vdev_t *vd; |
| |
| ASSERT(!BP_IS_HOLE(bp)); |
| ASSERT(!BP_IS_EMBEDDED(bp)); |
| ASSERT(psize > 0); |
| |
| spa_config_enter(spa, SCL_VDEV, FTAG, RW_READER); |
| |
| for (d = 0; d < ndvas; d++) { |
| if ((vd = vdev_lookup_top(spa, DVA_GET_VDEV(&dva[d]))) == NULL) |
| continue; |
| ASSERT3U(vd->vdev_pending_fastwrite, >=, psize); |
| atomic_sub_64(&vd->vdev_pending_fastwrite, psize); |
| } |
| |
| spa_config_exit(spa, SCL_VDEV, FTAG); |
| } |
| |
| /* ARGSUSED */ |
| static void |
| metaslab_check_free_impl_cb(uint64_t inner, vdev_t *vd, uint64_t offset, |
| uint64_t size, void *arg) |
| { |
| if (vd->vdev_ops == &vdev_indirect_ops) |
| return; |
| |
| metaslab_check_free_impl(vd, offset, size); |
| } |
| |
| static void |
| metaslab_check_free_impl(vdev_t *vd, uint64_t offset, uint64_t size) |
| { |
| metaslab_t *msp; |
| ASSERTV(spa_t *spa = vd->vdev_spa); |
| |
| if ((zfs_flags & ZFS_DEBUG_ZIO_FREE) == 0) |
| return; |
| |
| if (vd->vdev_ops->vdev_op_remap != NULL) { |
| vd->vdev_ops->vdev_op_remap(vd, offset, size, |
| metaslab_check_free_impl_cb, NULL); |
| return; |
| } |
| |
| ASSERT(vdev_is_concrete(vd)); |
| ASSERT3U(offset >> vd->vdev_ms_shift, <, vd->vdev_ms_count); |
| ASSERT3U(spa_config_held(spa, SCL_ALL, RW_READER), !=, 0); |
| |
| msp = vd->vdev_ms[offset >> vd->vdev_ms_shift]; |
| |
| mutex_enter(&msp->ms_lock); |
| if (msp->ms_loaded) { |
| range_tree_verify_not_present(msp->ms_allocatable, |
| offset, size); |
| } |
| |
| range_tree_verify_not_present(msp->ms_trim, offset, size); |
| range_tree_verify_not_present(msp->ms_freeing, offset, size); |
| range_tree_verify_not_present(msp->ms_checkpointing, offset, size); |
| range_tree_verify_not_present(msp->ms_freed, offset, size); |
| for (int j = 0; j < TXG_DEFER_SIZE; j++) |
| range_tree_verify_not_present(msp->ms_defer[j], offset, size); |
| mutex_exit(&msp->ms_lock); |
| } |
| |
| void |
| metaslab_check_free(spa_t *spa, const blkptr_t *bp) |
| { |
| if ((zfs_flags & ZFS_DEBUG_ZIO_FREE) == 0) |
| return; |
| |
| spa_config_enter(spa, SCL_VDEV, FTAG, RW_READER); |
| for (int i = 0; i < BP_GET_NDVAS(bp); i++) { |
| uint64_t vdev = DVA_GET_VDEV(&bp->blk_dva[i]); |
| vdev_t *vd = vdev_lookup_top(spa, vdev); |
| uint64_t offset = DVA_GET_OFFSET(&bp->blk_dva[i]); |
| uint64_t size = DVA_GET_ASIZE(&bp->blk_dva[i]); |
| |
| if (DVA_GET_GANG(&bp->blk_dva[i])) |
| size = vdev_psize_to_asize(vd, SPA_GANGBLOCKSIZE); |
| |
| ASSERT3P(vd, !=, NULL); |
| |
| metaslab_check_free_impl(vd, offset, size); |
| } |
| spa_config_exit(spa, SCL_VDEV, FTAG); |
| } |
| |
| static void |
| metaslab_group_disable_wait(metaslab_group_t *mg) |
| { |
| ASSERT(MUTEX_HELD(&mg->mg_ms_disabled_lock)); |
| while (mg->mg_disabled_updating) { |
| cv_wait(&mg->mg_ms_disabled_cv, &mg->mg_ms_disabled_lock); |
| } |
| } |
| |
| static void |
| metaslab_group_disabled_increment(metaslab_group_t *mg) |
| { |
| ASSERT(MUTEX_HELD(&mg->mg_ms_disabled_lock)); |
| ASSERT(mg->mg_disabled_updating); |
| |
| while (mg->mg_ms_disabled >= max_disabled_ms) { |
| cv_wait(&mg->mg_ms_disabled_cv, &mg->mg_ms_disabled_lock); |
| } |
| mg->mg_ms_disabled++; |
| ASSERT3U(mg->mg_ms_disabled, <=, max_disabled_ms); |
| } |
| |
| /* |
| * Mark the metaslab as disabled to prevent any allocations on this metaslab. |
| * We must also track how many metaslabs are currently disabled within a |
| * metaslab group and limit them to prevent allocation failures from |
| * occurring because all metaslabs are disabled. |
| */ |
| void |
| metaslab_disable(metaslab_t *msp) |
| { |
| ASSERT(!MUTEX_HELD(&msp->ms_lock)); |
| metaslab_group_t *mg = msp->ms_group; |
| |
| mutex_enter(&mg->mg_ms_disabled_lock); |
| |
| /* |
| * To keep an accurate count of how many threads have disabled |
| * a specific metaslab group, we only allow one thread to mark |
| * the metaslab group at a time. This ensures that the value of |
| * ms_disabled will be accurate when we decide to mark a metaslab |
| * group as disabled. To do this we force all other threads |
| * to wait till the metaslab's mg_disabled_updating flag is no |
| * longer set. |
| */ |
| metaslab_group_disable_wait(mg); |
| mg->mg_disabled_updating = B_TRUE; |
| if (msp->ms_disabled == 0) { |
| metaslab_group_disabled_increment(mg); |
| } |
| mutex_enter(&msp->ms_lock); |
| msp->ms_disabled++; |
| mutex_exit(&msp->ms_lock); |
| |
| mg->mg_disabled_updating = B_FALSE; |
| cv_broadcast(&mg->mg_ms_disabled_cv); |
| mutex_exit(&mg->mg_ms_disabled_lock); |
| } |
| |
| void |
| metaslab_enable(metaslab_t *msp, boolean_t sync) |
| { |
| metaslab_group_t *mg = msp->ms_group; |
| spa_t *spa = mg->mg_vd->vdev_spa; |
| |
| /* |
| * Wait for the outstanding IO to be synced to prevent newly |
| * allocated blocks from being overwritten. This used by |
| * initialize and TRIM which are modifying unallocated space. |
| */ |
| if (sync) |
| txg_wait_synced(spa_get_dsl(spa), 0); |
| |
| mutex_enter(&mg->mg_ms_disabled_lock); |
| mutex_enter(&msp->ms_lock); |
| if (--msp->ms_disabled == 0) { |
| mg->mg_ms_disabled--; |
| cv_broadcast(&mg->mg_ms_disabled_cv); |
| } |
| mutex_exit(&msp->ms_lock); |
| mutex_exit(&mg->mg_ms_disabled_lock); |
| } |
| |
| #if defined(_KERNEL) |
| /* BEGIN CSTYLED */ |
| module_param(metaslab_aliquot, ulong, 0644); |
| MODULE_PARM_DESC(metaslab_aliquot, |
| "allocation granularity (a.k.a. stripe size)"); |
| |
| module_param(metaslab_debug_load, int, 0644); |
| MODULE_PARM_DESC(metaslab_debug_load, |
| "load all metaslabs when pool is first opened"); |
| |
| module_param(metaslab_debug_unload, int, 0644); |
| MODULE_PARM_DESC(metaslab_debug_unload, |
| "prevent metaslabs from being unloaded"); |
| |
| module_param(metaslab_preload_enabled, int, 0644); |
| MODULE_PARM_DESC(metaslab_preload_enabled, |
| "preload potential metaslabs during reassessment"); |
| |
| module_param(zfs_mg_noalloc_threshold, int, 0644); |
| MODULE_PARM_DESC(zfs_mg_noalloc_threshold, |
| "percentage of free space for metaslab group to allow allocation"); |
| |
| module_param(zfs_mg_fragmentation_threshold, int, 0644); |
| MODULE_PARM_DESC(zfs_mg_fragmentation_threshold, |
| "fragmentation for metaslab group to allow allocation"); |
| |
| module_param(zfs_metaslab_fragmentation_threshold, int, 0644); |
| MODULE_PARM_DESC(zfs_metaslab_fragmentation_threshold, |
| "fragmentation for metaslab to allow allocation"); |
| |
| module_param(metaslab_fragmentation_factor_enabled, int, 0644); |
| MODULE_PARM_DESC(metaslab_fragmentation_factor_enabled, |
| "use the fragmentation metric to prefer less fragmented metaslabs"); |
| |
| module_param(metaslab_lba_weighting_enabled, int, 0644); |
| MODULE_PARM_DESC(metaslab_lba_weighting_enabled, |
| "prefer metaslabs with lower LBAs"); |
| |
| module_param(metaslab_bias_enabled, int, 0644); |
| MODULE_PARM_DESC(metaslab_bias_enabled, |
| "enable metaslab group biasing"); |
| |
| module_param(zfs_metaslab_segment_weight_enabled, int, 0644); |
| MODULE_PARM_DESC(zfs_metaslab_segment_weight_enabled, |
| "enable segment-based metaslab selection"); |
| |
| module_param(zfs_metaslab_switch_threshold, int, 0644); |
| MODULE_PARM_DESC(zfs_metaslab_switch_threshold, |
| "segment-based metaslab selection maximum buckets before switching"); |
| |
| module_param(metaslab_force_ganging, ulong, 0644); |
| MODULE_PARM_DESC(metaslab_force_ganging, |
| "blocks larger than this size are forced to be gang blocks"); |
| |
| module_param(metaslab_df_max_search, int, 0644); |
| MODULE_PARM_DESC(metaslab_df_max_search, |
| "max distance (bytes) to search forward before using size tree"); |
| |
| module_param(metaslab_df_use_largest_segment, int, 0644); |
| MODULE_PARM_DESC(metaslab_df_use_largest_segment, |
| "when looking in size tree, use largest segment instead of exact fit"); |
| /* END CSTYLED */ |
| |
| #endif |