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|
/*
* 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 https://opensource.org/licenses/CDDL-1.0.
* 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) 2016 by Delphix. All rights reserved.
* Copyright (c) 2019 by Lawrence Livermore National Security, LLC.
* Copyright (c) 2021 Hewlett Packard Enterprise Development LP
*/
#include <sys/spa.h>
#include <sys/spa_impl.h>
#include <sys/txg.h>
#include <sys/vdev_impl.h>
#include <sys/vdev_trim.h>
#include <sys/metaslab_impl.h>
#include <sys/dsl_synctask.h>
#include <sys/zap.h>
#include <sys/dmu_tx.h>
#include <sys/arc_impl.h>
/*
* TRIM is a feature which is used to notify a SSD that some previously
* written space is no longer allocated by the pool. This is useful because
* writes to a SSD must be performed to blocks which have first been erased.
* Ensuring the SSD always has a supply of erased blocks for new writes
* helps prevent the performance from deteriorating.
*
* There are two supported TRIM methods; manual and automatic.
*
* Manual TRIM:
*
* A manual TRIM is initiated by running the 'zpool trim' command. A single
* 'vdev_trim' thread is created for each leaf vdev, and it is responsible for
* managing that vdev TRIM process. This involves iterating over all the
* metaslabs, calculating the unallocated space ranges, and then issuing the
* required TRIM I/Os.
*
* While a metaslab is being actively trimmed it is not eligible to perform
* new allocations. After traversing all of the metaslabs the thread is
* terminated. Finally, both the requested options and current progress of
* the TRIM are regularly written to the pool. This allows the TRIM to be
* suspended and resumed as needed.
*
* Automatic TRIM:
*
* An automatic TRIM is enabled by setting the 'autotrim' pool property
* to 'on'. When enabled, a `vdev_autotrim' thread is created for each
* top-level (not leaf) vdev in the pool. These threads perform the same
* core TRIM process as a manual TRIM, but with a few key differences.
*
* 1) Automatic TRIM happens continuously in the background and operates
* solely on recently freed blocks (ms_trim not ms_allocatable).
*
* 2) Each thread is associated with a top-level (not leaf) vdev. This has
* the benefit of simplifying the threading model, it makes it easier
* to coordinate administrative commands, and it ensures only a single
* metaslab is disabled at a time. Unlike manual TRIM, this means each
* 'vdev_autotrim' thread is responsible for issuing TRIM I/Os for its
* children.
*
* 3) There is no automatic TRIM progress information stored on disk, nor
* is it reported by 'zpool status'.
*
* While the automatic TRIM process is highly effective it is more likely
* than a manual TRIM to encounter tiny ranges. Ranges less than or equal to
* 'zfs_trim_extent_bytes_min' (32k) are considered too small to efficiently
* TRIM and are skipped. This means small amounts of freed space may not
* be automatically trimmed.
*
* Furthermore, devices with attached hot spares and devices being actively
* replaced are skipped. This is done to avoid adding additional stress to
* a potentially unhealthy device and to minimize the required rebuild time.
*
* For this reason it may be beneficial to occasionally manually TRIM a pool
* even when automatic TRIM is enabled.
*/
/*
* Maximum size of TRIM I/O, ranges will be chunked in to 128MiB lengths.
*/
static unsigned int zfs_trim_extent_bytes_max = 128 * 1024 * 1024;
/*
* Minimum size of TRIM I/O, extents smaller than 32Kib will be skipped.
*/
static unsigned int zfs_trim_extent_bytes_min = 32 * 1024;
/*
* Skip uninitialized metaslabs during the TRIM process. This option is
* useful for pools constructed from large thinly-provisioned devices where
* TRIM operations are slow. As a pool ages an increasing fraction of
* the pools metaslabs will be initialized progressively degrading the
* usefulness of this option. This setting is stored when starting a
* manual TRIM and will persist for the duration of the requested TRIM.
*/
unsigned int zfs_trim_metaslab_skip = 0;
/*
* Maximum number of queued TRIM I/Os per leaf vdev. The number of
* concurrent TRIM I/Os issued to the device is controlled by the
* zfs_vdev_trim_min_active and zfs_vdev_trim_max_active module options.
*/
static unsigned int zfs_trim_queue_limit = 10;
/*
* The minimum number of transaction groups between automatic trims of a
* metaslab. This setting represents a trade-off between issuing more
* efficient TRIM operations, by allowing them to be aggregated longer,
* and issuing them promptly so the trimmed space is available. Note
* that this value is a minimum; metaslabs can be trimmed less frequently
* when there are a large number of ranges which need to be trimmed.
*
* Increasing this value will allow frees to be aggregated for a longer
* time. This can result is larger TRIM operations, and increased memory
* usage in order to track the ranges to be trimmed. Decreasing this value
* has the opposite effect. The default value of 32 was determined though
* testing to be a reasonable compromise.
*/
static unsigned int zfs_trim_txg_batch = 32;
/*
* The trim_args are a control structure which describe how a leaf vdev
* should be trimmed. The core elements are the vdev, the metaslab being
* trimmed and a range tree containing the extents to TRIM. All provided
* ranges must be within the metaslab.
*/
typedef struct trim_args {
/*
* These fields are set by the caller of vdev_trim_ranges().
*/
vdev_t *trim_vdev; /* Leaf vdev to TRIM */
metaslab_t *trim_msp; /* Disabled metaslab */
range_tree_t *trim_tree; /* TRIM ranges (in metaslab) */
trim_type_t trim_type; /* Manual or auto TRIM */
uint64_t trim_extent_bytes_max; /* Maximum TRIM I/O size */
uint64_t trim_extent_bytes_min; /* Minimum TRIM I/O size */
enum trim_flag trim_flags; /* TRIM flags (secure) */
/*
* These fields are updated by vdev_trim_ranges().
*/
hrtime_t trim_start_time; /* Start time */
uint64_t trim_bytes_done; /* Bytes trimmed */
} trim_args_t;
/*
* Determines whether a vdev_trim_thread() should be stopped.
*/
static boolean_t
vdev_trim_should_stop(vdev_t *vd)
{
return (vd->vdev_trim_exit_wanted || !vdev_writeable(vd) ||
vd->vdev_detached || vd->vdev_top->vdev_removing);
}
/*
* Determines whether a vdev_autotrim_thread() should be stopped.
*/
static boolean_t
vdev_autotrim_should_stop(vdev_t *tvd)
{
return (tvd->vdev_autotrim_exit_wanted ||
!vdev_writeable(tvd) || tvd->vdev_removing ||
spa_get_autotrim(tvd->vdev_spa) == SPA_AUTOTRIM_OFF);
}
/*
* The sync task for updating the on-disk state of a manual TRIM. This
* is scheduled by vdev_trim_change_state().
*/
static void
vdev_trim_zap_update_sync(void *arg, dmu_tx_t *tx)
{
/*
* We pass in the guid instead of the vdev_t since the vdev may
* have been freed prior to the sync task being processed. This
* happens when a vdev is detached as we call spa_config_vdev_exit(),
* stop the trimming thread, schedule the sync task, and free
* the vdev. Later when the scheduled sync task is invoked, it would
* find that the vdev has been freed.
*/
uint64_t guid = *(uint64_t *)arg;
uint64_t txg = dmu_tx_get_txg(tx);
kmem_free(arg, sizeof (uint64_t));
vdev_t *vd = spa_lookup_by_guid(tx->tx_pool->dp_spa, guid, B_FALSE);
if (vd == NULL || vd->vdev_top->vdev_removing || !vdev_is_concrete(vd))
return;
uint64_t last_offset = vd->vdev_trim_offset[txg & TXG_MASK];
vd->vdev_trim_offset[txg & TXG_MASK] = 0;
VERIFY3U(vd->vdev_leaf_zap, !=, 0);
objset_t *mos = vd->vdev_spa->spa_meta_objset;
if (last_offset > 0 || vd->vdev_trim_last_offset == UINT64_MAX) {
if (vd->vdev_trim_last_offset == UINT64_MAX)
last_offset = 0;
vd->vdev_trim_last_offset = last_offset;
VERIFY0(zap_update(mos, vd->vdev_leaf_zap,
VDEV_LEAF_ZAP_TRIM_LAST_OFFSET,
sizeof (last_offset), 1, &last_offset, tx));
}
if (vd->vdev_trim_action_time > 0) {
uint64_t val = (uint64_t)vd->vdev_trim_action_time;
VERIFY0(zap_update(mos, vd->vdev_leaf_zap,
VDEV_LEAF_ZAP_TRIM_ACTION_TIME, sizeof (val),
1, &val, tx));
}
if (vd->vdev_trim_rate > 0) {
uint64_t rate = (uint64_t)vd->vdev_trim_rate;
if (rate == UINT64_MAX)
rate = 0;
VERIFY0(zap_update(mos, vd->vdev_leaf_zap,
VDEV_LEAF_ZAP_TRIM_RATE, sizeof (rate), 1, &rate, tx));
}
uint64_t partial = vd->vdev_trim_partial;
if (partial == UINT64_MAX)
partial = 0;
VERIFY0(zap_update(mos, vd->vdev_leaf_zap, VDEV_LEAF_ZAP_TRIM_PARTIAL,
sizeof (partial), 1, &partial, tx));
uint64_t secure = vd->vdev_trim_secure;
if (secure == UINT64_MAX)
secure = 0;
VERIFY0(zap_update(mos, vd->vdev_leaf_zap, VDEV_LEAF_ZAP_TRIM_SECURE,
sizeof (secure), 1, &secure, tx));
uint64_t trim_state = vd->vdev_trim_state;
VERIFY0(zap_update(mos, vd->vdev_leaf_zap, VDEV_LEAF_ZAP_TRIM_STATE,
sizeof (trim_state), 1, &trim_state, tx));
}
/*
* Update the on-disk state of a manual TRIM. This is called to request
* that a TRIM be started/suspended/canceled, or to change one of the
* TRIM options (partial, secure, rate).
*/
static void
vdev_trim_change_state(vdev_t *vd, vdev_trim_state_t new_state,
uint64_t rate, boolean_t partial, boolean_t secure)
{
ASSERT(MUTEX_HELD(&vd->vdev_trim_lock));
spa_t *spa = vd->vdev_spa;
if (new_state == vd->vdev_trim_state)
return;
/*
* Copy the vd's guid, this will be freed by the sync task.
*/
uint64_t *guid = kmem_zalloc(sizeof (uint64_t), KM_SLEEP);
*guid = vd->vdev_guid;
/*
* If we're suspending, then preserve the original start time.
*/
if (vd->vdev_trim_state != VDEV_TRIM_SUSPENDED) {
vd->vdev_trim_action_time = gethrestime_sec();
}
/*
* If we're activating, then preserve the requested rate and trim
* method. Setting the last offset and rate to UINT64_MAX is used
* as a sentinel to indicate they should be reset to default values.
*/
if (new_state == VDEV_TRIM_ACTIVE) {
if (vd->vdev_trim_state == VDEV_TRIM_COMPLETE ||
vd->vdev_trim_state == VDEV_TRIM_CANCELED) {
vd->vdev_trim_last_offset = UINT64_MAX;
vd->vdev_trim_rate = UINT64_MAX;
vd->vdev_trim_partial = UINT64_MAX;
vd->vdev_trim_secure = UINT64_MAX;
}
if (rate != 0)
vd->vdev_trim_rate = rate;
if (partial != 0)
vd->vdev_trim_partial = partial;
if (secure != 0)
vd->vdev_trim_secure = secure;
}
vdev_trim_state_t old_state = vd->vdev_trim_state;
boolean_t resumed = (old_state == VDEV_TRIM_SUSPENDED);
vd->vdev_trim_state = new_state;
dmu_tx_t *tx = dmu_tx_create_dd(spa_get_dsl(spa)->dp_mos_dir);
VERIFY0(dmu_tx_assign(tx, TXG_WAIT));
dsl_sync_task_nowait(spa_get_dsl(spa), vdev_trim_zap_update_sync,
guid, tx);
switch (new_state) {
case VDEV_TRIM_ACTIVE:
spa_event_notify(spa, vd, NULL,
resumed ? ESC_ZFS_TRIM_RESUME : ESC_ZFS_TRIM_START);
spa_history_log_internal(spa, "trim", tx,
"vdev=%s activated", vd->vdev_path);
break;
case VDEV_TRIM_SUSPENDED:
spa_event_notify(spa, vd, NULL, ESC_ZFS_TRIM_SUSPEND);
spa_history_log_internal(spa, "trim", tx,
"vdev=%s suspended", vd->vdev_path);
break;
case VDEV_TRIM_CANCELED:
if (old_state == VDEV_TRIM_ACTIVE ||
old_state == VDEV_TRIM_SUSPENDED) {
spa_event_notify(spa, vd, NULL, ESC_ZFS_TRIM_CANCEL);
spa_history_log_internal(spa, "trim", tx,
"vdev=%s canceled", vd->vdev_path);
}
break;
case VDEV_TRIM_COMPLETE:
spa_event_notify(spa, vd, NULL, ESC_ZFS_TRIM_FINISH);
spa_history_log_internal(spa, "trim", tx,
"vdev=%s complete", vd->vdev_path);
break;
default:
panic("invalid state %llu", (unsigned long long)new_state);
}
dmu_tx_commit(tx);
if (new_state != VDEV_TRIM_ACTIVE)
spa_notify_waiters(spa);
}
/*
* The zio_done_func_t done callback for each manual TRIM issued. It is
* responsible for updating the TRIM stats, reissuing failed TRIM I/Os,
* and limiting the number of in flight TRIM I/Os.
*/
static void
vdev_trim_cb(zio_t *zio)
{
vdev_t *vd = zio->io_vd;
mutex_enter(&vd->vdev_trim_io_lock);
if (zio->io_error == ENXIO && !vdev_writeable(vd)) {
/*
* The I/O failed because the vdev was unavailable; roll the
* last offset back. (This works because spa_sync waits on
* spa_txg_zio before it runs sync tasks.)
*/
uint64_t *offset =
&vd->vdev_trim_offset[zio->io_txg & TXG_MASK];
*offset = MIN(*offset, zio->io_offset);
} else {
if (zio->io_error != 0) {
vd->vdev_stat.vs_trim_errors++;
spa_iostats_trim_add(vd->vdev_spa, TRIM_TYPE_MANUAL,
0, 0, 0, 0, 1, zio->io_orig_size);
} else {
spa_iostats_trim_add(vd->vdev_spa, TRIM_TYPE_MANUAL,
1, zio->io_orig_size, 0, 0, 0, 0);
}
vd->vdev_trim_bytes_done += zio->io_orig_size;
}
ASSERT3U(vd->vdev_trim_inflight[TRIM_TYPE_MANUAL], >, 0);
vd->vdev_trim_inflight[TRIM_TYPE_MANUAL]--;
cv_broadcast(&vd->vdev_trim_io_cv);
mutex_exit(&vd->vdev_trim_io_lock);
spa_config_exit(vd->vdev_spa, SCL_STATE_ALL, vd);
}
/*
* The zio_done_func_t done callback for each automatic TRIM issued. It
* is responsible for updating the TRIM stats and limiting the number of
* in flight TRIM I/Os. Automatic TRIM I/Os are best effort and are
* never reissued on failure.
*/
static void
vdev_autotrim_cb(zio_t *zio)
{
vdev_t *vd = zio->io_vd;
mutex_enter(&vd->vdev_trim_io_lock);
if (zio->io_error != 0) {
vd->vdev_stat.vs_trim_errors++;
spa_iostats_trim_add(vd->vdev_spa, TRIM_TYPE_AUTO,
0, 0, 0, 0, 1, zio->io_orig_size);
} else {
spa_iostats_trim_add(vd->vdev_spa, TRIM_TYPE_AUTO,
1, zio->io_orig_size, 0, 0, 0, 0);
}
ASSERT3U(vd->vdev_trim_inflight[TRIM_TYPE_AUTO], >, 0);
vd->vdev_trim_inflight[TRIM_TYPE_AUTO]--;
cv_broadcast(&vd->vdev_trim_io_cv);
mutex_exit(&vd->vdev_trim_io_lock);
spa_config_exit(vd->vdev_spa, SCL_STATE_ALL, vd);
}
/*
* The zio_done_func_t done callback for each TRIM issued via
* vdev_trim_simple(). It is responsible for updating the TRIM stats and
* limiting the number of in flight TRIM I/Os. Simple TRIM I/Os are best
* effort and are never reissued on failure.
*/
static void
vdev_trim_simple_cb(zio_t *zio)
{
vdev_t *vd = zio->io_vd;
mutex_enter(&vd->vdev_trim_io_lock);
if (zio->io_error != 0) {
vd->vdev_stat.vs_trim_errors++;
spa_iostats_trim_add(vd->vdev_spa, TRIM_TYPE_SIMPLE,
0, 0, 0, 0, 1, zio->io_orig_size);
} else {
spa_iostats_trim_add(vd->vdev_spa, TRIM_TYPE_SIMPLE,
1, zio->io_orig_size, 0, 0, 0, 0);
}
ASSERT3U(vd->vdev_trim_inflight[TRIM_TYPE_SIMPLE], >, 0);
vd->vdev_trim_inflight[TRIM_TYPE_SIMPLE]--;
cv_broadcast(&vd->vdev_trim_io_cv);
mutex_exit(&vd->vdev_trim_io_lock);
spa_config_exit(vd->vdev_spa, SCL_STATE_ALL, vd);
}
/*
* Returns the average trim rate in bytes/sec for the ta->trim_vdev.
*/
static uint64_t
vdev_trim_calculate_rate(trim_args_t *ta)
{
return (ta->trim_bytes_done * 1000 /
(NSEC2MSEC(gethrtime() - ta->trim_start_time) + 1));
}
/*
* Issues a physical TRIM and takes care of rate limiting (bytes/sec)
* and number of concurrent TRIM I/Os.
*/
static int
vdev_trim_range(trim_args_t *ta, uint64_t start, uint64_t size)
{
vdev_t *vd = ta->trim_vdev;
spa_t *spa = vd->vdev_spa;
void *cb;
mutex_enter(&vd->vdev_trim_io_lock);
/*
* Limit manual TRIM I/Os to the requested rate. This does not
* apply to automatic TRIM since no per vdev rate can be specified.
*/
if (ta->trim_type == TRIM_TYPE_MANUAL) {
while (vd->vdev_trim_rate != 0 && !vdev_trim_should_stop(vd) &&
vdev_trim_calculate_rate(ta) > vd->vdev_trim_rate) {
cv_timedwait_idle(&vd->vdev_trim_io_cv,
&vd->vdev_trim_io_lock, ddi_get_lbolt() +
MSEC_TO_TICK(10));
}
}
ta->trim_bytes_done += size;
/* Limit in flight trimming I/Os */
while (vd->vdev_trim_inflight[0] + vd->vdev_trim_inflight[1] +
vd->vdev_trim_inflight[2] >= zfs_trim_queue_limit) {
cv_wait(&vd->vdev_trim_io_cv, &vd->vdev_trim_io_lock);
}
vd->vdev_trim_inflight[ta->trim_type]++;
mutex_exit(&vd->vdev_trim_io_lock);
dmu_tx_t *tx = dmu_tx_create_dd(spa_get_dsl(spa)->dp_mos_dir);
VERIFY0(dmu_tx_assign(tx, TXG_WAIT));
uint64_t txg = dmu_tx_get_txg(tx);
spa_config_enter(spa, SCL_STATE_ALL, vd, RW_READER);
mutex_enter(&vd->vdev_trim_lock);
if (ta->trim_type == TRIM_TYPE_MANUAL &&
vd->vdev_trim_offset[txg & TXG_MASK] == 0) {
uint64_t *guid = kmem_zalloc(sizeof (uint64_t), KM_SLEEP);
*guid = vd->vdev_guid;
/* This is the first write of this txg. */
dsl_sync_task_nowait(spa_get_dsl(spa),
vdev_trim_zap_update_sync, guid, tx);
}
/*
* We know the vdev_t will still be around since all consumers of
* vdev_free must stop the trimming first.
*/
if ((ta->trim_type == TRIM_TYPE_MANUAL &&
vdev_trim_should_stop(vd)) ||
(ta->trim_type == TRIM_TYPE_AUTO &&
vdev_autotrim_should_stop(vd->vdev_top))) {
mutex_enter(&vd->vdev_trim_io_lock);
vd->vdev_trim_inflight[ta->trim_type]--;
mutex_exit(&vd->vdev_trim_io_lock);
spa_config_exit(vd->vdev_spa, SCL_STATE_ALL, vd);
mutex_exit(&vd->vdev_trim_lock);
dmu_tx_commit(tx);
return (SET_ERROR(EINTR));
}
mutex_exit(&vd->vdev_trim_lock);
if (ta->trim_type == TRIM_TYPE_MANUAL)
vd->vdev_trim_offset[txg & TXG_MASK] = start + size;
if (ta->trim_type == TRIM_TYPE_MANUAL) {
cb = vdev_trim_cb;
} else if (ta->trim_type == TRIM_TYPE_AUTO) {
cb = vdev_autotrim_cb;
} else {
cb = vdev_trim_simple_cb;
}
zio_nowait(zio_trim(spa->spa_txg_zio[txg & TXG_MASK], vd,
start, size, cb, NULL, ZIO_PRIORITY_TRIM, ZIO_FLAG_CANFAIL,
ta->trim_flags));
/* vdev_trim_cb and vdev_autotrim_cb release SCL_STATE_ALL */
dmu_tx_commit(tx);
return (0);
}
/*
* Issues TRIM I/Os for all ranges in the provided ta->trim_tree range tree.
* Additional parameters describing how the TRIM should be performed must
* be set in the trim_args structure. See the trim_args definition for
* additional information.
*/
static int
vdev_trim_ranges(trim_args_t *ta)
{
vdev_t *vd = ta->trim_vdev;
zfs_btree_t *t = &ta->trim_tree->rt_root;
zfs_btree_index_t idx;
uint64_t extent_bytes_max = ta->trim_extent_bytes_max;
uint64_t extent_bytes_min = ta->trim_extent_bytes_min;
spa_t *spa = vd->vdev_spa;
ta->trim_start_time = gethrtime();
ta->trim_bytes_done = 0;
for (range_seg_t *rs = zfs_btree_first(t, &idx); rs != NULL;
rs = zfs_btree_next(t, &idx, &idx)) {
uint64_t size = rs_get_end(rs, ta->trim_tree) - rs_get_start(rs,
ta->trim_tree);
if (extent_bytes_min && size < extent_bytes_min) {
spa_iostats_trim_add(spa, ta->trim_type,
0, 0, 1, size, 0, 0);
continue;
}
/* Split range into legally-sized physical chunks */
uint64_t writes_required = ((size - 1) / extent_bytes_max) + 1;
for (uint64_t w = 0; w < writes_required; w++) {
int error;
error = vdev_trim_range(ta, VDEV_LABEL_START_SIZE +
rs_get_start(rs, ta->trim_tree) +
(w *extent_bytes_max), MIN(size -
(w * extent_bytes_max), extent_bytes_max));
if (error != 0) {
return (error);
}
}
}
return (0);
}
static void
vdev_trim_xlate_last_rs_end(void *arg, range_seg64_t *physical_rs)
{
uint64_t *last_rs_end = (uint64_t *)arg;
if (physical_rs->rs_end > *last_rs_end)
*last_rs_end = physical_rs->rs_end;
}
static void
vdev_trim_xlate_progress(void *arg, range_seg64_t *physical_rs)
{
vdev_t *vd = (vdev_t *)arg;
uint64_t size = physical_rs->rs_end - physical_rs->rs_start;
vd->vdev_trim_bytes_est += size;
if (vd->vdev_trim_last_offset >= physical_rs->rs_end) {
vd->vdev_trim_bytes_done += size;
} else if (vd->vdev_trim_last_offset > physical_rs->rs_start &&
vd->vdev_trim_last_offset <= physical_rs->rs_end) {
vd->vdev_trim_bytes_done +=
vd->vdev_trim_last_offset - physical_rs->rs_start;
}
}
/*
* Calculates the completion percentage of a manual TRIM.
*/
static void
vdev_trim_calculate_progress(vdev_t *vd)
{
ASSERT(spa_config_held(vd->vdev_spa, SCL_CONFIG, RW_READER) ||
spa_config_held(vd->vdev_spa, SCL_CONFIG, RW_WRITER));
ASSERT(vd->vdev_leaf_zap != 0);
vd->vdev_trim_bytes_est = 0;
vd->vdev_trim_bytes_done = 0;
for (uint64_t i = 0; i < vd->vdev_top->vdev_ms_count; i++) {
metaslab_t *msp = vd->vdev_top->vdev_ms[i];
mutex_enter(&msp->ms_lock);
uint64_t ms_free = (msp->ms_size -
metaslab_allocated_space(msp)) /
vdev_get_ndisks(vd->vdev_top);
/*
* Convert the metaslab range to a physical range
* on our vdev. We use this to determine if we are
* in the middle of this metaslab range.
*/
range_seg64_t logical_rs, physical_rs, remain_rs;
logical_rs.rs_start = msp->ms_start;
logical_rs.rs_end = msp->ms_start + msp->ms_size;
/* Metaslab space after this offset has not been trimmed. */
vdev_xlate(vd, &logical_rs, &physical_rs, &remain_rs);
if (vd->vdev_trim_last_offset <= physical_rs.rs_start) {
vd->vdev_trim_bytes_est += ms_free;
mutex_exit(&msp->ms_lock);
continue;
}
/* Metaslab space before this offset has been trimmed */
uint64_t last_rs_end = physical_rs.rs_end;
if (!vdev_xlate_is_empty(&remain_rs)) {
vdev_xlate_walk(vd, &remain_rs,
vdev_trim_xlate_last_rs_end, &last_rs_end);
}
if (vd->vdev_trim_last_offset > last_rs_end) {
vd->vdev_trim_bytes_done += ms_free;
vd->vdev_trim_bytes_est += ms_free;
mutex_exit(&msp->ms_lock);
continue;
}
/*
* If we get here, we're in the middle of trimming this
* metaslab. Load it and walk the free tree for more
* accurate progress estimation.
*/
VERIFY0(metaslab_load(msp));
range_tree_t *rt = msp->ms_allocatable;
zfs_btree_t *bt = &rt->rt_root;
zfs_btree_index_t idx;
for (range_seg_t *rs = zfs_btree_first(bt, &idx);
rs != NULL; rs = zfs_btree_next(bt, &idx, &idx)) {
logical_rs.rs_start = rs_get_start(rs, rt);
logical_rs.rs_end = rs_get_end(rs, rt);
vdev_xlate_walk(vd, &logical_rs,
vdev_trim_xlate_progress, vd);
}
mutex_exit(&msp->ms_lock);
}
}
/*
* Load from disk the vdev's manual TRIM information. This includes the
* state, progress, and options provided when initiating the manual TRIM.
*/
static int
vdev_trim_load(vdev_t *vd)
{
int err = 0;
ASSERT(spa_config_held(vd->vdev_spa, SCL_CONFIG, RW_READER) ||
spa_config_held(vd->vdev_spa, SCL_CONFIG, RW_WRITER));
ASSERT(vd->vdev_leaf_zap != 0);
if (vd->vdev_trim_state == VDEV_TRIM_ACTIVE ||
vd->vdev_trim_state == VDEV_TRIM_SUSPENDED) {
err = zap_lookup(vd->vdev_spa->spa_meta_objset,
vd->vdev_leaf_zap, VDEV_LEAF_ZAP_TRIM_LAST_OFFSET,
sizeof (vd->vdev_trim_last_offset), 1,
&vd->vdev_trim_last_offset);
if (err == ENOENT) {
vd->vdev_trim_last_offset = 0;
err = 0;
}
if (err == 0) {
err = zap_lookup(vd->vdev_spa->spa_meta_objset,
vd->vdev_leaf_zap, VDEV_LEAF_ZAP_TRIM_RATE,
sizeof (vd->vdev_trim_rate), 1,
&vd->vdev_trim_rate);
if (err == ENOENT) {
vd->vdev_trim_rate = 0;
err = 0;
}
}
if (err == 0) {
err = zap_lookup(vd->vdev_spa->spa_meta_objset,
vd->vdev_leaf_zap, VDEV_LEAF_ZAP_TRIM_PARTIAL,
sizeof (vd->vdev_trim_partial), 1,
&vd->vdev_trim_partial);
if (err == ENOENT) {
vd->vdev_trim_partial = 0;
err = 0;
}
}
if (err == 0) {
err = zap_lookup(vd->vdev_spa->spa_meta_objset,
vd->vdev_leaf_zap, VDEV_LEAF_ZAP_TRIM_SECURE,
sizeof (vd->vdev_trim_secure), 1,
&vd->vdev_trim_secure);
if (err == ENOENT) {
vd->vdev_trim_secure = 0;
err = 0;
}
}
}
vdev_trim_calculate_progress(vd);
return (err);
}
static void
vdev_trim_xlate_range_add(void *arg, range_seg64_t *physical_rs)
{
trim_args_t *ta = arg;
vdev_t *vd = ta->trim_vdev;
/*
* Only a manual trim will be traversing the vdev sequentially.
* For an auto trim all valid ranges should be added.
*/
if (ta->trim_type == TRIM_TYPE_MANUAL) {
/* Only add segments that we have not visited yet */
if (physical_rs->rs_end <= vd->vdev_trim_last_offset)
return;
/* Pick up where we left off mid-range. */
if (vd->vdev_trim_last_offset > physical_rs->rs_start) {
ASSERT3U(physical_rs->rs_end, >,
vd->vdev_trim_last_offset);
physical_rs->rs_start = vd->vdev_trim_last_offset;
}
}
ASSERT3U(physical_rs->rs_end, >, physical_rs->rs_start);
range_tree_add(ta->trim_tree, physical_rs->rs_start,
physical_rs->rs_end - physical_rs->rs_start);
}
/*
* Convert the logical range into physical ranges and add them to the
* range tree passed in the trim_args_t.
*/
static void
vdev_trim_range_add(void *arg, uint64_t start, uint64_t size)
{
trim_args_t *ta = arg;
vdev_t *vd = ta->trim_vdev;
range_seg64_t logical_rs;
logical_rs.rs_start = start;
logical_rs.rs_end = start + size;
/*
* Every range to be trimmed must be part of ms_allocatable.
* When ZFS_DEBUG_TRIM is set load the metaslab to verify this
* is always the case.
*/
if (zfs_flags & ZFS_DEBUG_TRIM) {
metaslab_t *msp = ta->trim_msp;
VERIFY0(metaslab_load(msp));
VERIFY3B(msp->ms_loaded, ==, B_TRUE);
VERIFY(range_tree_contains(msp->ms_allocatable, start, size));
}
ASSERT(vd->vdev_ops->vdev_op_leaf);
vdev_xlate_walk(vd, &logical_rs, vdev_trim_xlate_range_add, arg);
}
/*
* Each manual TRIM thread is responsible for trimming the unallocated
* space for each leaf vdev. This is accomplished by sequentially iterating
* over its top-level metaslabs and issuing TRIM I/O for the space described
* by its ms_allocatable. While a metaslab is undergoing trimming it is
* not eligible for new allocations.
*/
static __attribute__((noreturn)) void
vdev_trim_thread(void *arg)
{
vdev_t *vd = arg;
spa_t *spa = vd->vdev_spa;
trim_args_t ta;
int error = 0;
/*
* The VDEV_LEAF_ZAP_TRIM_* entries may have been updated by
* vdev_trim(). Wait for the updated values to be reflected
* in the zap in order to start with the requested settings.
*/
txg_wait_synced(spa_get_dsl(vd->vdev_spa), 0);
ASSERT(vdev_is_concrete(vd));
spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
vd->vdev_trim_last_offset = 0;
vd->vdev_trim_rate = 0;
vd->vdev_trim_partial = 0;
vd->vdev_trim_secure = 0;
VERIFY0(vdev_trim_load(vd));
ta.trim_vdev = vd;
ta.trim_extent_bytes_max = zfs_trim_extent_bytes_max;
ta.trim_extent_bytes_min = zfs_trim_extent_bytes_min;
ta.trim_tree = range_tree_create(NULL, RANGE_SEG64, NULL, 0, 0);
ta.trim_type = TRIM_TYPE_MANUAL;
ta.trim_flags = 0;
/*
* When a secure TRIM has been requested infer that the intent
* is that everything must be trimmed. Override the default
* minimum TRIM size to prevent ranges from being skipped.
*/
if (vd->vdev_trim_secure) {
ta.trim_flags |= ZIO_TRIM_SECURE;
ta.trim_extent_bytes_min = SPA_MINBLOCKSIZE;
}
uint64_t ms_count = 0;
for (uint64_t i = 0; !vd->vdev_detached &&
i < vd->vdev_top->vdev_ms_count; i++) {
metaslab_t *msp = vd->vdev_top->vdev_ms[i];
/*
* If we've expanded the top-level vdev or it's our
* first pass, calculate our progress.
*/
if (vd->vdev_top->vdev_ms_count != ms_count) {
vdev_trim_calculate_progress(vd);
ms_count = vd->vdev_top->vdev_ms_count;
}
spa_config_exit(spa, SCL_CONFIG, FTAG);
metaslab_disable(msp);
mutex_enter(&msp->ms_lock);
VERIFY0(metaslab_load(msp));
/*
* If a partial TRIM was requested skip metaslabs which have
* never been initialized and thus have never been written.
*/
if (msp->ms_sm == NULL && vd->vdev_trim_partial) {
mutex_exit(&msp->ms_lock);
metaslab_enable(msp, B_FALSE, B_FALSE);
spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
vdev_trim_calculate_progress(vd);
continue;
}
ta.trim_msp = msp;
range_tree_walk(msp->ms_allocatable, vdev_trim_range_add, &ta);
range_tree_vacate(msp->ms_trim, NULL, NULL);
mutex_exit(&msp->ms_lock);
error = vdev_trim_ranges(&ta);
metaslab_enable(msp, B_TRUE, B_FALSE);
spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
range_tree_vacate(ta.trim_tree, NULL, NULL);
if (error != 0)
break;
}
spa_config_exit(spa, SCL_CONFIG, FTAG);
mutex_enter(&vd->vdev_trim_io_lock);
while (vd->vdev_trim_inflight[0] > 0) {
cv_wait(&vd->vdev_trim_io_cv, &vd->vdev_trim_io_lock);
}
mutex_exit(&vd->vdev_trim_io_lock);
range_tree_destroy(ta.trim_tree);
mutex_enter(&vd->vdev_trim_lock);
if (!vd->vdev_trim_exit_wanted) {
if (vdev_writeable(vd)) {
vdev_trim_change_state(vd, VDEV_TRIM_COMPLETE,
vd->vdev_trim_rate, vd->vdev_trim_partial,
vd->vdev_trim_secure);
} else if (vd->vdev_faulted) {
vdev_trim_change_state(vd, VDEV_TRIM_CANCELED,
vd->vdev_trim_rate, vd->vdev_trim_partial,
vd->vdev_trim_secure);
}
}
ASSERT(vd->vdev_trim_thread != NULL || vd->vdev_trim_inflight[0] == 0);
/*
* Drop the vdev_trim_lock while we sync out the txg since it's
* possible that a device might be trying to come online and must
* check to see if it needs to restart a trim. That thread will be
* holding the spa_config_lock which would prevent the txg_wait_synced
* from completing.
*/
mutex_exit(&vd->vdev_trim_lock);
txg_wait_synced(spa_get_dsl(spa), 0);
mutex_enter(&vd->vdev_trim_lock);
vd->vdev_trim_thread = NULL;
cv_broadcast(&vd->vdev_trim_cv);
mutex_exit(&vd->vdev_trim_lock);
thread_exit();
}
/*
* Initiates a manual TRIM for the vdev_t. Callers must hold vdev_trim_lock,
* the vdev_t must be a leaf and cannot already be manually trimming.
*/
void
vdev_trim(vdev_t *vd, uint64_t rate, boolean_t partial, boolean_t secure)
{
ASSERT(MUTEX_HELD(&vd->vdev_trim_lock));
ASSERT(vd->vdev_ops->vdev_op_leaf);
ASSERT(vdev_is_concrete(vd));
ASSERT3P(vd->vdev_trim_thread, ==, NULL);
ASSERT(!vd->vdev_detached);
ASSERT(!vd->vdev_trim_exit_wanted);
ASSERT(!vd->vdev_top->vdev_removing);
vdev_trim_change_state(vd, VDEV_TRIM_ACTIVE, rate, partial, secure);
vd->vdev_trim_thread = thread_create(NULL, 0,
vdev_trim_thread, vd, 0, &p0, TS_RUN, maxclsyspri);
}
/*
* Wait for the trimming thread to be terminated (canceled or stopped).
*/
static void
vdev_trim_stop_wait_impl(vdev_t *vd)
{
ASSERT(MUTEX_HELD(&vd->vdev_trim_lock));
while (vd->vdev_trim_thread != NULL)
cv_wait(&vd->vdev_trim_cv, &vd->vdev_trim_lock);
ASSERT3P(vd->vdev_trim_thread, ==, NULL);
vd->vdev_trim_exit_wanted = B_FALSE;
}
/*
* Wait for vdev trim threads which were listed to cleanly exit.
*/
void
vdev_trim_stop_wait(spa_t *spa, list_t *vd_list)
{
(void) spa;
vdev_t *vd;
ASSERT(MUTEX_HELD(&spa_namespace_lock));
while ((vd = list_remove_head(vd_list)) != NULL) {
mutex_enter(&vd->vdev_trim_lock);
vdev_trim_stop_wait_impl(vd);
mutex_exit(&vd->vdev_trim_lock);
}
}
/*
* Stop trimming a device, with the resultant trimming state being tgt_state.
* For blocking behavior pass NULL for vd_list. Otherwise, when a list_t is
* provided the stopping vdev is inserted in to the list. Callers are then
* required to call vdev_trim_stop_wait() to block for all the trim threads
* to exit. The caller must hold vdev_trim_lock and must not be writing to
* the spa config, as the trimming thread may try to enter the config as a
* reader before exiting.
*/
void
vdev_trim_stop(vdev_t *vd, vdev_trim_state_t tgt_state, list_t *vd_list)
{
ASSERT(!spa_config_held(vd->vdev_spa, SCL_CONFIG|SCL_STATE, RW_WRITER));
ASSERT(MUTEX_HELD(&vd->vdev_trim_lock));
ASSERT(vd->vdev_ops->vdev_op_leaf);
ASSERT(vdev_is_concrete(vd));
/*
* Allow cancel requests to proceed even if the trim thread has
* stopped.
*/
if (vd->vdev_trim_thread == NULL && tgt_state != VDEV_TRIM_CANCELED)
return;
vdev_trim_change_state(vd, tgt_state, 0, 0, 0);
vd->vdev_trim_exit_wanted = B_TRUE;
if (vd_list == NULL) {
vdev_trim_stop_wait_impl(vd);
} else {
ASSERT(MUTEX_HELD(&spa_namespace_lock));
list_insert_tail(vd_list, vd);
}
}
/*
* Requests that all listed vdevs stop trimming.
*/
static void
vdev_trim_stop_all_impl(vdev_t *vd, vdev_trim_state_t tgt_state,
list_t *vd_list)
{
if (vd->vdev_ops->vdev_op_leaf && vdev_is_concrete(vd)) {
mutex_enter(&vd->vdev_trim_lock);
vdev_trim_stop(vd, tgt_state, vd_list);
mutex_exit(&vd->vdev_trim_lock);
return;
}
for (uint64_t i = 0; i < vd->vdev_children; i++) {
vdev_trim_stop_all_impl(vd->vdev_child[i], tgt_state,
vd_list);
}
}
/*
* Convenience function to stop trimming of a vdev tree and set all trim
* thread pointers to NULL.
*/
void
vdev_trim_stop_all(vdev_t *vd, vdev_trim_state_t tgt_state)
{
spa_t *spa = vd->vdev_spa;
list_t vd_list;
vdev_t *vd_l2cache;
ASSERT(MUTEX_HELD(&spa_namespace_lock));
list_create(&vd_list, sizeof (vdev_t),
offsetof(vdev_t, vdev_trim_node));
vdev_trim_stop_all_impl(vd, tgt_state, &vd_list);
/*
* Iterate over cache devices and request stop trimming the
* whole device in case we export the pool or remove the cache
* device prematurely.
*/
for (int i = 0; i < spa->spa_l2cache.sav_count; i++) {
vd_l2cache = spa->spa_l2cache.sav_vdevs[i];
vdev_trim_stop_all_impl(vd_l2cache, tgt_state, &vd_list);
}
vdev_trim_stop_wait(spa, &vd_list);
if (vd->vdev_spa->spa_sync_on) {
/* Make sure that our state has been synced to disk */
txg_wait_synced(spa_get_dsl(vd->vdev_spa), 0);
}
list_destroy(&vd_list);
}
/*
* Conditionally restarts a manual TRIM given its on-disk state.
*/
void
vdev_trim_restart(vdev_t *vd)
{
ASSERT(MUTEX_HELD(&spa_namespace_lock));
ASSERT(!spa_config_held(vd->vdev_spa, SCL_ALL, RW_WRITER));
if (vd->vdev_leaf_zap != 0) {
mutex_enter(&vd->vdev_trim_lock);
uint64_t trim_state = VDEV_TRIM_NONE;
int err = zap_lookup(vd->vdev_spa->spa_meta_objset,
vd->vdev_leaf_zap, VDEV_LEAF_ZAP_TRIM_STATE,
sizeof (trim_state), 1, &trim_state);
ASSERT(err == 0 || err == ENOENT);
vd->vdev_trim_state = trim_state;
uint64_t timestamp = 0;
err = zap_lookup(vd->vdev_spa->spa_meta_objset,
vd->vdev_leaf_zap, VDEV_LEAF_ZAP_TRIM_ACTION_TIME,
sizeof (timestamp), 1, ×tamp);
ASSERT(err == 0 || err == ENOENT);
vd->vdev_trim_action_time = timestamp;
if (vd->vdev_trim_state == VDEV_TRIM_SUSPENDED ||
vd->vdev_offline) {
/* load progress for reporting, but don't resume */
VERIFY0(vdev_trim_load(vd));
} else if (vd->vdev_trim_state == VDEV_TRIM_ACTIVE &&
vdev_writeable(vd) && !vd->vdev_top->vdev_removing &&
vd->vdev_trim_thread == NULL) {
VERIFY0(vdev_trim_load(vd));
vdev_trim(vd, vd->vdev_trim_rate,
vd->vdev_trim_partial, vd->vdev_trim_secure);
}
mutex_exit(&vd->vdev_trim_lock);
}
for (uint64_t i = 0; i < vd->vdev_children; i++) {
vdev_trim_restart(vd->vdev_child[i]);
}
}
/*
* Used by the automatic TRIM when ZFS_DEBUG_TRIM is set to verify that
* every TRIM range is contained within ms_allocatable.
*/
static void
vdev_trim_range_verify(void *arg, uint64_t start, uint64_t size)
{
trim_args_t *ta = arg;
metaslab_t *msp = ta->trim_msp;
VERIFY3B(msp->ms_loaded, ==, B_TRUE);
VERIFY3U(msp->ms_disabled, >, 0);
VERIFY(range_tree_contains(msp->ms_allocatable, start, size));
}
/*
* Each automatic TRIM thread is responsible for managing the trimming of a
* top-level vdev in the pool. No automatic TRIM state is maintained on-disk.
*
* N.B. This behavior is different from a manual TRIM where a thread
* is created for each leaf vdev, instead of each top-level vdev.
*/
static __attribute__((noreturn)) void
vdev_autotrim_thread(void *arg)
{
vdev_t *vd = arg;
spa_t *spa = vd->vdev_spa;
int shift = 0;
mutex_enter(&vd->vdev_autotrim_lock);
ASSERT3P(vd->vdev_top, ==, vd);
ASSERT3P(vd->vdev_autotrim_thread, !=, NULL);
mutex_exit(&vd->vdev_autotrim_lock);
spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
uint64_t extent_bytes_max = zfs_trim_extent_bytes_max;
uint64_t extent_bytes_min = zfs_trim_extent_bytes_min;
while (!vdev_autotrim_should_stop(vd)) {
int txgs_per_trim = MAX(zfs_trim_txg_batch, 1);
boolean_t issued_trim = B_FALSE;
/*
* All of the metaslabs are divided in to groups of size
* num_metaslabs / zfs_trim_txg_batch. Each of these groups
* is composed of metaslabs which are spread evenly over the
* device.
*
* For example, when zfs_trim_txg_batch = 32 (default) then
* group 0 will contain metaslabs 0, 32, 64, ...;
* group 1 will contain metaslabs 1, 33, 65, ...;
* group 2 will contain metaslabs 2, 34, 66, ...; and so on.
*
* On each pass through the while() loop one of these groups
* is selected. This is accomplished by using a shift value
* to select the starting metaslab, then striding over the
* metaslabs using the zfs_trim_txg_batch size. This is
* done to accomplish two things.
*
* 1) By dividing the metaslabs in to groups, and making sure
* that each group takes a minimum of one txg to process.
* Then zfs_trim_txg_batch controls the minimum number of
* txgs which must occur before a metaslab is revisited.
*
* 2) Selecting non-consecutive metaslabs distributes the
* TRIM commands for a group evenly over the entire device.
* This can be advantageous for certain types of devices.
*/
for (uint64_t i = shift % txgs_per_trim; i < vd->vdev_ms_count;
i += txgs_per_trim) {
metaslab_t *msp = vd->vdev_ms[i];
range_tree_t *trim_tree;
spa_config_exit(spa, SCL_CONFIG, FTAG);
metaslab_disable(msp);
spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
mutex_enter(&msp->ms_lock);
/*
* Skip the metaslab when it has never been allocated
* or when there are no recent frees to trim.
*/
if (msp->ms_sm == NULL ||
range_tree_is_empty(msp->ms_trim)) {
mutex_exit(&msp->ms_lock);
metaslab_enable(msp, B_FALSE, B_FALSE);
continue;
}
/*
* Skip the metaslab when it has already been disabled.
* This may happen when a manual TRIM or initialize
* operation is running concurrently. In the case
* of a manual TRIM, the ms_trim tree will have been
* vacated. Only ranges added after the manual TRIM
* disabled the metaslab will be included in the tree.
* These will be processed when the automatic TRIM
* next revisits this metaslab.
*/
if (msp->ms_disabled > 1) {
mutex_exit(&msp->ms_lock);
metaslab_enable(msp, B_FALSE, B_FALSE);
continue;
}
/*
* Allocate an empty range tree which is swapped in
* for the existing ms_trim tree while it is processed.
*/
trim_tree = range_tree_create(NULL, RANGE_SEG64, NULL,
0, 0);
range_tree_swap(&msp->ms_trim, &trim_tree);
ASSERT(range_tree_is_empty(msp->ms_trim));
/*
* There are two cases when constructing the per-vdev
* trim trees for a metaslab. If the top-level vdev
* has no children then it is also a leaf and should
* be trimmed. Otherwise our children are the leaves
* and a trim tree should be constructed for each.
*/
trim_args_t *tap;
uint64_t children = vd->vdev_children;
if (children == 0) {
children = 1;
tap = kmem_zalloc(sizeof (trim_args_t) *
children, KM_SLEEP);
tap[0].trim_vdev = vd;
} else {
tap = kmem_zalloc(sizeof (trim_args_t) *
children, KM_SLEEP);
for (uint64_t c = 0; c < children; c++) {
tap[c].trim_vdev = vd->vdev_child[c];
}
}
for (uint64_t c = 0; c < children; c++) {
trim_args_t *ta = &tap[c];
vdev_t *cvd = ta->trim_vdev;
ta->trim_msp = msp;
ta->trim_extent_bytes_max = extent_bytes_max;
ta->trim_extent_bytes_min = extent_bytes_min;
ta->trim_type = TRIM_TYPE_AUTO;
ta->trim_flags = 0;
if (cvd->vdev_detached ||
!vdev_writeable(cvd) ||
!cvd->vdev_has_trim ||
cvd->vdev_trim_thread != NULL) {
continue;
}
/*
* When a device has an attached hot spare, or
* is being replaced it will not be trimmed.
* This is done to avoid adding additional
* stress to a potentially unhealthy device,
* and to minimize the required rebuild time.
*/
if (!cvd->vdev_ops->vdev_op_leaf)
continue;
ta->trim_tree = range_tree_create(NULL,
RANGE_SEG64, NULL, 0, 0);
range_tree_walk(trim_tree,
vdev_trim_range_add, ta);
}
mutex_exit(&msp->ms_lock);
spa_config_exit(spa, SCL_CONFIG, FTAG);
/*
* Issue the TRIM I/Os for all ranges covered by the
* TRIM trees. These ranges are safe to TRIM because
* no new allocations will be performed until the call
* to metaslab_enabled() below.
*/
for (uint64_t c = 0; c < children; c++) {
trim_args_t *ta = &tap[c];
/*
* Always yield to a manual TRIM if one has
* been started for the child vdev.
*/
if (ta->trim_tree == NULL ||
ta->trim_vdev->vdev_trim_thread != NULL) {
continue;
}
/*
* After this point metaslab_enable() must be
* called with the sync flag set. This is done
* here because vdev_trim_ranges() is allowed
* to be interrupted (EINTR) before issuing all
* of the required TRIM I/Os.
*/
issued_trim = B_TRUE;
int error = vdev_trim_ranges(ta);
if (error)
break;
}
/*
* Verify every range which was trimmed is still
* contained within the ms_allocatable tree.
*/
if (zfs_flags & ZFS_DEBUG_TRIM) {
mutex_enter(&msp->ms_lock);
VERIFY0(metaslab_load(msp));
VERIFY3P(tap[0].trim_msp, ==, msp);
range_tree_walk(trim_tree,
vdev_trim_range_verify, &tap[0]);
mutex_exit(&msp->ms_lock);
}
range_tree_vacate(trim_tree, NULL, NULL);
range_tree_destroy(trim_tree);
metaslab_enable(msp, issued_trim, B_FALSE);
spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
for (uint64_t c = 0; c < children; c++) {
trim_args_t *ta = &tap[c];
if (ta->trim_tree == NULL)
continue;
range_tree_vacate(ta->trim_tree, NULL, NULL);
range_tree_destroy(ta->trim_tree);
}
kmem_free(tap, sizeof (trim_args_t) * children);
}
spa_config_exit(spa, SCL_CONFIG, FTAG);
/*
* After completing the group of metaslabs wait for the next
* open txg. This is done to make sure that a minimum of
* zfs_trim_txg_batch txgs will occur before these metaslabs
* are trimmed again.
*/
txg_wait_open(spa_get_dsl(spa), 0, issued_trim);
shift++;
spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
}
for (uint64_t c = 0; c < vd->vdev_children; c++) {
vdev_t *cvd = vd->vdev_child[c];
mutex_enter(&cvd->vdev_trim_io_lock);
while (cvd->vdev_trim_inflight[1] > 0) {
cv_wait(&cvd->vdev_trim_io_cv,
&cvd->vdev_trim_io_lock);
}
mutex_exit(&cvd->vdev_trim_io_lock);
}
spa_config_exit(spa, SCL_CONFIG, FTAG);
/*
* When exiting because the autotrim property was set to off, then
* abandon any unprocessed ms_trim ranges to reclaim the memory.
*/
if (spa_get_autotrim(spa) == SPA_AUTOTRIM_OFF) {
for (uint64_t i = 0; i < vd->vdev_ms_count; i++) {
metaslab_t *msp = vd->vdev_ms[i];
mutex_enter(&msp->ms_lock);
range_tree_vacate(msp->ms_trim, NULL, NULL);
mutex_exit(&msp->ms_lock);
}
}
mutex_enter(&vd->vdev_autotrim_lock);
ASSERT(vd->vdev_autotrim_thread != NULL);
vd->vdev_autotrim_thread = NULL;
cv_broadcast(&vd->vdev_autotrim_cv);
mutex_exit(&vd->vdev_autotrim_lock);
thread_exit();
}
/*
* Starts an autotrim thread, if needed, for each top-level vdev which can be
* trimmed. A top-level vdev which has been evacuated will never be trimmed.
*/
void
vdev_autotrim(spa_t *spa)
{
vdev_t *root_vd = spa->spa_root_vdev;
for (uint64_t i = 0; i < root_vd->vdev_children; i++) {
vdev_t *tvd = root_vd->vdev_child[i];
mutex_enter(&tvd->vdev_autotrim_lock);
if (vdev_writeable(tvd) && !tvd->vdev_removing &&
tvd->vdev_autotrim_thread == NULL) {
ASSERT3P(tvd->vdev_top, ==, tvd);
tvd->vdev_autotrim_thread = thread_create(NULL, 0,
vdev_autotrim_thread, tvd, 0, &p0, TS_RUN,
maxclsyspri);
ASSERT(tvd->vdev_autotrim_thread != NULL);
}
mutex_exit(&tvd->vdev_autotrim_lock);
}
}
/*
* Wait for the vdev_autotrim_thread associated with the passed top-level
* vdev to be terminated (canceled or stopped).
*/
void
vdev_autotrim_stop_wait(vdev_t *tvd)
{
mutex_enter(&tvd->vdev_autotrim_lock);
if (tvd->vdev_autotrim_thread != NULL) {
tvd->vdev_autotrim_exit_wanted = B_TRUE;
while (tvd->vdev_autotrim_thread != NULL) {
cv_wait(&tvd->vdev_autotrim_cv,
&tvd->vdev_autotrim_lock);
}
ASSERT3P(tvd->vdev_autotrim_thread, ==, NULL);
tvd->vdev_autotrim_exit_wanted = B_FALSE;
}
mutex_exit(&tvd->vdev_autotrim_lock);
}
/*
* Wait for all of the vdev_autotrim_thread associated with the pool to
* be terminated (canceled or stopped).
*/
void
vdev_autotrim_stop_all(spa_t *spa)
{
vdev_t *root_vd = spa->spa_root_vdev;
for (uint64_t i = 0; i < root_vd->vdev_children; i++)
vdev_autotrim_stop_wait(root_vd->vdev_child[i]);
}
/*
* Conditionally restart all of the vdev_autotrim_thread's for the pool.
*/
void
vdev_autotrim_restart(spa_t *spa)
{
ASSERT(MUTEX_HELD(&spa_namespace_lock));
if (spa->spa_autotrim)
vdev_autotrim(spa);
}
static __attribute__((noreturn)) void
vdev_trim_l2arc_thread(void *arg)
{
vdev_t *vd = arg;
spa_t *spa = vd->vdev_spa;
l2arc_dev_t *dev = l2arc_vdev_get(vd);
trim_args_t ta = {0};
range_seg64_t physical_rs;
ASSERT(vdev_is_concrete(vd));
spa_config_enter(spa, SCL_CONFIG, FTAG, RW_READER);
vd->vdev_trim_last_offset = 0;
vd->vdev_trim_rate = 0;
vd->vdev_trim_partial = 0;
vd->vdev_trim_secure = 0;
ta.trim_vdev = vd;
ta.trim_tree = range_tree_create(NULL, RANGE_SEG64, NULL, 0, 0);
ta.trim_type = TRIM_TYPE_MANUAL;
ta.trim_extent_bytes_max = zfs_trim_extent_bytes_max;
ta.trim_extent_bytes_min = SPA_MINBLOCKSIZE;
ta.trim_flags = 0;
physical_rs.rs_start = vd->vdev_trim_bytes_done = 0;
physical_rs.rs_end = vd->vdev_trim_bytes_est =
vdev_get_min_asize(vd);
range_tree_add(ta.trim_tree, physical_rs.rs_start,
physical_rs.rs_end - physical_rs.rs_start);
mutex_enter(&vd->vdev_trim_lock);
vdev_trim_change_state(vd, VDEV_TRIM_ACTIVE, 0, 0, 0);
mutex_exit(&vd->vdev_trim_lock);
(void) vdev_trim_ranges(&ta);
spa_config_exit(spa, SCL_CONFIG, FTAG);
mutex_enter(&vd->vdev_trim_io_lock);
while (vd->vdev_trim_inflight[TRIM_TYPE_MANUAL] > 0) {
cv_wait(&vd->vdev_trim_io_cv, &vd->vdev_trim_io_lock);
}
mutex_exit(&vd->vdev_trim_io_lock);
range_tree_vacate(ta.trim_tree, NULL, NULL);
range_tree_destroy(ta.trim_tree);
mutex_enter(&vd->vdev_trim_lock);
if (!vd->vdev_trim_exit_wanted && vdev_writeable(vd)) {
vdev_trim_change_state(vd, VDEV_TRIM_COMPLETE,
vd->vdev_trim_rate, vd->vdev_trim_partial,
vd->vdev_trim_secure);
}
ASSERT(vd->vdev_trim_thread != NULL ||
vd->vdev_trim_inflight[TRIM_TYPE_MANUAL] == 0);
/*
* Drop the vdev_trim_lock while we sync out the txg since it's
* possible that a device might be trying to come online and
* must check to see if it needs to restart a trim. That thread
* will be holding the spa_config_lock which would prevent the
* txg_wait_synced from completing. Same strategy as in
* vdev_trim_thread().
*/
mutex_exit(&vd->vdev_trim_lock);
txg_wait_synced(spa_get_dsl(vd->vdev_spa), 0);
mutex_enter(&vd->vdev_trim_lock);
/*
* Update the header of the cache device here, before
* broadcasting vdev_trim_cv which may lead to the removal
* of the device. The same applies for setting l2ad_trim_all to
* false.
*/
spa_config_enter(vd->vdev_spa, SCL_L2ARC, vd,
RW_READER);
memset(dev->l2ad_dev_hdr, 0, dev->l2ad_dev_hdr_asize);
l2arc_dev_hdr_update(dev);
spa_config_exit(vd->vdev_spa, SCL_L2ARC, vd);
vd->vdev_trim_thread = NULL;
if (vd->vdev_trim_state == VDEV_TRIM_COMPLETE)
dev->l2ad_trim_all = B_FALSE;
cv_broadcast(&vd->vdev_trim_cv);
mutex_exit(&vd->vdev_trim_lock);
thread_exit();
}
/*
* Punches out TRIM threads for the L2ARC devices in a spa and assigns them
* to vd->vdev_trim_thread variable. This facilitates the management of
* trimming the whole cache device using TRIM_TYPE_MANUAL upon addition
* to a pool or pool creation or when the header of the device is invalid.
*/
void
vdev_trim_l2arc(spa_t *spa)
{
ASSERT(MUTEX_HELD(&spa_namespace_lock));
/*
* Locate the spa's l2arc devices and kick off TRIM threads.
*/
for (int i = 0; i < spa->spa_l2cache.sav_count; i++) {
vdev_t *vd = spa->spa_l2cache.sav_vdevs[i];
l2arc_dev_t *dev = l2arc_vdev_get(vd);
if (dev == NULL || !dev->l2ad_trim_all) {
/*
* Don't attempt TRIM if the vdev is UNAVAIL or if the
* cache device was not marked for whole device TRIM
* (ie l2arc_trim_ahead = 0, or the L2ARC device header
* is valid with trim_state = VDEV_TRIM_COMPLETE and
* l2ad_log_entries > 0).
*/
continue;
}
mutex_enter(&vd->vdev_trim_lock);
ASSERT(vd->vdev_ops->vdev_op_leaf);
ASSERT(vdev_is_concrete(vd));
ASSERT3P(vd->vdev_trim_thread, ==, NULL);
ASSERT(!vd->vdev_detached);
ASSERT(!vd->vdev_trim_exit_wanted);
ASSERT(!vd->vdev_top->vdev_removing);
vdev_trim_change_state(vd, VDEV_TRIM_ACTIVE, 0, 0, 0);
vd->vdev_trim_thread = thread_create(NULL, 0,
vdev_trim_l2arc_thread, vd, 0, &p0, TS_RUN, maxclsyspri);
mutex_exit(&vd->vdev_trim_lock);
}
}
/*
* A wrapper which calls vdev_trim_ranges(). It is intended to be called
* on leaf vdevs.
*/
int
vdev_trim_simple(vdev_t *vd, uint64_t start, uint64_t size)
{
trim_args_t ta = {0};
range_seg64_t physical_rs;
int error;
physical_rs.rs_start = start;
physical_rs.rs_end = start + size;
ASSERT(vdev_is_concrete(vd));
ASSERT(vd->vdev_ops->vdev_op_leaf);
ASSERT(!vd->vdev_detached);
ASSERT(!vd->vdev_top->vdev_removing);
ta.trim_vdev = vd;
ta.trim_tree = range_tree_create(NULL, RANGE_SEG64, NULL, 0, 0);
ta.trim_type = TRIM_TYPE_SIMPLE;
ta.trim_extent_bytes_max = zfs_trim_extent_bytes_max;
ta.trim_extent_bytes_min = SPA_MINBLOCKSIZE;
ta.trim_flags = 0;
ASSERT3U(physical_rs.rs_end, >=, physical_rs.rs_start);
if (physical_rs.rs_end > physical_rs.rs_start) {
range_tree_add(ta.trim_tree, physical_rs.rs_start,
physical_rs.rs_end - physical_rs.rs_start);
} else {
ASSERT3U(physical_rs.rs_end, ==, physical_rs.rs_start);
}
error = vdev_trim_ranges(&ta);
mutex_enter(&vd->vdev_trim_io_lock);
while (vd->vdev_trim_inflight[TRIM_TYPE_SIMPLE] > 0) {
cv_wait(&vd->vdev_trim_io_cv, &vd->vdev_trim_io_lock);
}
mutex_exit(&vd->vdev_trim_io_lock);
range_tree_vacate(ta.trim_tree, NULL, NULL);
range_tree_destroy(ta.trim_tree);
return (error);
}
EXPORT_SYMBOL(vdev_trim);
EXPORT_SYMBOL(vdev_trim_stop);
EXPORT_SYMBOL(vdev_trim_stop_all);
EXPORT_SYMBOL(vdev_trim_stop_wait);
EXPORT_SYMBOL(vdev_trim_restart);
EXPORT_SYMBOL(vdev_autotrim);
EXPORT_SYMBOL(vdev_autotrim_stop_all);
EXPORT_SYMBOL(vdev_autotrim_stop_wait);
EXPORT_SYMBOL(vdev_autotrim_restart);
EXPORT_SYMBOL(vdev_trim_l2arc);
EXPORT_SYMBOL(vdev_trim_simple);
ZFS_MODULE_PARAM(zfs_trim, zfs_trim_, extent_bytes_max, UINT, ZMOD_RW,
"Max size of TRIM commands, larger will be split");
ZFS_MODULE_PARAM(zfs_trim, zfs_trim_, extent_bytes_min, UINT, ZMOD_RW,
"Min size of TRIM commands, smaller will be skipped");
ZFS_MODULE_PARAM(zfs_trim, zfs_trim_, metaslab_skip, UINT, ZMOD_RW,
"Skip metaslabs which have never been initialized");
ZFS_MODULE_PARAM(zfs_trim, zfs_trim_, txg_batch, UINT, ZMOD_RW,
"Min number of txgs to aggregate frees before issuing TRIM");
ZFS_MODULE_PARAM(zfs_trim, zfs_trim_, queue_limit, UINT, ZMOD_RW,
"Max queued TRIMs outstanding per leaf vdev");
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