On 2020/05/13 16:07, Hannes Reinecke wrote:
> Instead of emulating zones on the regular disk as random zones
> this patch adds a new 'cache' zone type.
> This allows us to use the random zones on the zoned disk as
> data zones (if cache zones are present), and improves performance
> as the zones on the (slower) zoned disk are then never used
> for caching.
>
> Signed-off-by: Hannes Reinecke <[email protected]>
> ---
> .../admin-guide/device-mapper/dm-zoned.rst | 17 +-
> drivers/md/dm-zoned-metadata.c | 145 ++++++++++++++----
> drivers/md/dm-zoned-reclaim.c | 70 +++++----
> drivers/md/dm-zoned-target.c | 19 ++-
> drivers/md/dm-zoned.h | 7 +-
> 5 files changed, 181 insertions(+), 77 deletions(-)
>
> diff --git a/Documentation/admin-guide/device-mapper/dm-zoned.rst
> b/Documentation/admin-guide/device-mapper/dm-zoned.rst
> index 553752ea2521..d4933638737a 100644
> --- a/Documentation/admin-guide/device-mapper/dm-zoned.rst
> +++ b/Documentation/admin-guide/device-mapper/dm-zoned.rst
> @@ -174,17 +174,18 @@ Ex::
>
> will return a line
>
> - 0 <size> zoned <nr_zones> zones <nr_unmap_rnd>/<nr_rnd> random
> <nr_unmap_seq>/<nr_seq> sequential
> + 0 <size> zoned <nr_zones> zones <nr_unmap/nr_total> cache
> <nr_unmap>/<nr_total> random <nr_unmap>/<nr_total> sequential
>
> -where <nr_zones> is the total number of zones, <nr_unmap_rnd> is the number
> -of unmapped (ie free) random zones, <nr_rnd> the total number of zones,
> -<nr_unmap_seq> the number of unmapped sequential zones, and <nr_seq> the
> -total number of sequential zones.
> +where <nr_zones> is the total number of zones, followed by statistics for
> +the zone types (cache, random, and sequential), where <nr_unmap>/<nr_total>
> +is the number of unmapped (ie free) vs the overall number of zones.
> +'cache' zones are located on the regular disk, 'random' and 'sequential'
> +on the zoned disk.
>
> Normally the reclaim process will be started once there are less than 50
> -percent free random zones. In order to start the reclaim process manually
> -even before reaching this threshold the 'dmsetup message' function can be
> -used:
> +percent free cache or random zones. In order to start the reclaim process
> +manually even before reaching this threshold the 'dmsetup message' function
> +can be used:
>
> Ex::
>
> diff --git a/drivers/md/dm-zoned-metadata.c b/drivers/md/dm-zoned-metadata.c
> index 9b93d7ff1dfc..dbcbcb0ddf56 100644
> --- a/drivers/md/dm-zoned-metadata.c
> +++ b/drivers/md/dm-zoned-metadata.c
> @@ -166,6 +166,7 @@ struct dmz_metadata {
> unsigned int nr_meta_blocks;
> unsigned int nr_meta_zones;
> unsigned int nr_data_zones;
> + unsigned int nr_cache_zones;
> unsigned int nr_rnd_zones;
> unsigned int nr_reserved_seq;
> unsigned int nr_chunks;
> @@ -196,6 +197,11 @@ struct dmz_metadata {
> struct list_head unmap_rnd_list;
> struct list_head map_rnd_list;
>
> + unsigned int nr_cache;
> + atomic_t unmap_nr_cache;
> + struct list_head unmap_cache_list;
> + struct list_head map_cache_list;
> +
> unsigned int nr_seq;
> atomic_t unmap_nr_seq;
> struct list_head unmap_seq_list;
> @@ -301,6 +307,16 @@ unsigned int dmz_nr_unmap_rnd_zones(struct dmz_metadata
> *zmd)
> return atomic_read(&zmd->unmap_nr_rnd);
> }
>
> +unsigned int dmz_nr_cache_zones(struct dmz_metadata *zmd)
> +{
> + return zmd->nr_cache;
> +}
> +
> +unsigned int dmz_nr_unmap_cache_zones(struct dmz_metadata *zmd)
> +{
> + return atomic_read(&zmd->unmap_nr_cache);
> +}
> +
> unsigned int dmz_nr_seq_zones(struct dmz_metadata *zmd)
> {
> return zmd->nr_seq;
> @@ -1390,9 +1406,9 @@ static void dmz_emulate_zones(struct dmz_metadata *zmd,
> struct dmz_dev *dev)
> atomic_set(&zone->refcount, 0);
> zone->id = idx;
> zone->chunk = DMZ_MAP_UNMAPPED;
> - set_bit(DMZ_RND, &zone->flags);
> + set_bit(DMZ_CACHE, &zone->flags);
> zone->wp_block = 0;
> - zmd->nr_rnd_zones++;
> + zmd->nr_cache_zones++;
> zmd->nr_useable_zones++;
> if (dev->capacity - zone_offset < zmd->zone_nr_sectors) {
> /* Disable runt zone */
> @@ -1651,7 +1667,9 @@ static int dmz_load_mapping(struct dmz_metadata *zmd)
> dzone->chunk = chunk;
> dmz_get_zone_weight(zmd, dzone);
>
> - if (dmz_is_rnd(dzone))
> + if (dmz_is_cache(dzone))
> + list_add_tail(&dzone->link, &zmd->map_cache_list);
> + else if (dmz_is_rnd(dzone))
> list_add_tail(&dzone->link, &zmd->map_rnd_list);
> else
> list_add_tail(&dzone->link, &zmd->map_seq_list);
> @@ -1668,7 +1686,7 @@ static int dmz_load_mapping(struct dmz_metadata *zmd)
> }
>
> bzone = dmz_get(zmd, bzone_id);
> - if (!dmz_is_rnd(bzone)) {
> + if (!dmz_is_rnd(bzone) && !dmz_is_cache(bzone)) {
> dmz_zmd_err(zmd, "Chunk %u mapping: invalid buffer zone
> %u",
> chunk, bzone_id);
> return -EIO;
> @@ -1680,7 +1698,10 @@ static int dmz_load_mapping(struct dmz_metadata *zmd)
> bzone->bzone = dzone;
> dzone->bzone = bzone;
> dmz_get_zone_weight(zmd, bzone);
> - list_add_tail(&bzone->link, &zmd->map_rnd_list);
> + if (dmz_is_cache(bzone))
> + list_add_tail(&bzone->link, &zmd->map_cache_list);
> + else
> + list_add_tail(&bzone->link, &zmd->map_rnd_list);
> next:
> chunk++;
> e++;
> @@ -1697,8 +1718,12 @@ static int dmz_load_mapping(struct dmz_metadata *zmd)
> dzone = dmz_get(zmd, i);
> if (dmz_is_meta(dzone))
> continue;
> + if (dmz_is_offline(dzone))
> + continue;
>
> - if (dmz_is_rnd(dzone))
> + if (dmz_is_cache(dzone))
> + zmd->nr_cache++;
> + else if (dmz_is_rnd(dzone))
> zmd->nr_rnd++;
> else
> zmd->nr_seq++;
> @@ -1711,7 +1736,10 @@ static int dmz_load_mapping(struct dmz_metadata *zmd)
> /* Unmapped data zone */
> set_bit(DMZ_DATA, &dzone->flags);
> dzone->chunk = DMZ_MAP_UNMAPPED;
> - if (dmz_is_rnd(dzone)) {
> + if (dmz_is_cache(dzone)) {
> + list_add_tail(&dzone->link, &zmd->unmap_cache_list);
> + atomic_inc(&zmd->unmap_nr_cache);
> + } else if (dmz_is_rnd(dzone)) {
> list_add_tail(&dzone->link, &zmd->unmap_rnd_list);
> atomic_inc(&zmd->unmap_nr_rnd);
> } else if (atomic_read(&zmd->nr_reserved_seq_zones) <
> zmd->nr_reserved_seq) {
> @@ -1755,6 +1783,9 @@ static void __dmz_lru_zone(struct dmz_metadata *zmd,
> struct dm_zone *zone)
> if (dmz_is_seq(zone)) {
> /* LRU rotate sequential zone */
> list_add_tail(&zone->link, &zmd->map_seq_list);
> + } else if (dmz_is_cache(zone)) {
> + /* LRU rotate cache zone */
> + list_add_tail(&zone->link, &zmd->map_cache_list);
> } else {
> /* LRU rotate random zone */
> list_add_tail(&zone->link, &zmd->map_rnd_list);
> @@ -1830,17 +1861,19 @@ static void dmz_wait_for_reclaim(struct dmz_metadata
> *zmd, struct dm_zone *zone)
> }
>
> /*
> - * Select a random write zone for reclaim.
> + * Select a cache or random write zone for reclaim.
> */
> static struct dm_zone *dmz_get_rnd_zone_for_reclaim(struct dmz_metadata *zmd)
> {
> struct dm_zone *dzone = NULL;
> struct dm_zone *zone;
> + struct list_head *zone_list = &zmd->map_rnd_list;
>
> - if (list_empty(&zmd->map_rnd_list))
> - return ERR_PTR(-EBUSY);
> + /* If we have cache zones select from the cache zone list */
> + if (zmd->nr_cache)
> + zone_list = &zmd->map_cache_list;
>
> - list_for_each_entry(zone, &zmd->map_rnd_list, link) {
> + list_for_each_entry(zone, zone_list, link) {
> if (dmz_is_buf(zone))
> dzone = zone->bzone;
> else
> @@ -1853,15 +1886,21 @@ static struct dm_zone
> *dmz_get_rnd_zone_for_reclaim(struct dmz_metadata *zmd)
> }
>
> /*
> - * Select a buffered sequential zone for reclaim.
> + * Select a buffered random write or sequential zone for reclaim.
Random write zoned should never be "buffered", or to be very precise, they will
be only during the time reclaim moves a cache zone data to a random zone. That
is visible in the dmz_handle_write() change that execute
dmz_handle_direct_write() for cache or buffered zones instead of using
dmz_handle_buffered_write(). So I think this comment can stay as is.
> */
> static struct dm_zone *dmz_get_seq_zone_for_reclaim(struct dmz_metadata *zmd)
> {
> struct dm_zone *zone;
>
> - if (list_empty(&zmd->map_seq_list))
> - return ERR_PTR(-EBUSY);
> -
> + if (zmd->nr_cache) {
> + /* If we have cache zones start with random zones */
> + list_for_each_entry(zone, &zmd->map_rnd_list, link) {
> + if (!zone->bzone)
> + continue;
> + if (dmz_lock_zone_reclaim(zone))
> + return zone;
> + }
> + }
For the reason stated above, I think this change is not necessary either.
> list_for_each_entry(zone, &zmd->map_seq_list, link) {
> if (!zone->bzone)
> continue;
> @@ -1911,6 +1950,7 @@ struct dm_zone *dmz_get_chunk_mapping(struct
> dmz_metadata *zmd, unsigned int chu
> unsigned int dzone_id;
> struct dm_zone *dzone = NULL;
> int ret = 0;
> + int alloc_flags = zmd->nr_cache ? DMZ_ALLOC_CACHE : DMZ_ALLOC_RND;
>
> dmz_lock_map(zmd);
> again:
> @@ -1925,7 +1965,7 @@ struct dm_zone *dmz_get_chunk_mapping(struct
> dmz_metadata *zmd, unsigned int chu
> goto out;
>
> /* Allocate a random zone */
> - dzone = dmz_alloc_zone(zmd, DMZ_ALLOC_RND);
> + dzone = dmz_alloc_zone(zmd, alloc_flags);
> if (!dzone) {
> if (dmz_dev_is_dying(zmd)) {
> dzone = ERR_PTR(-EIO);
> @@ -2018,6 +2058,7 @@ struct dm_zone *dmz_get_chunk_buffer(struct
> dmz_metadata *zmd,
> struct dm_zone *dzone)
> {
> struct dm_zone *bzone;
> + int alloc_flags = zmd->nr_cache ? DMZ_ALLOC_CACHE : DMZ_ALLOC_RND;
>
> dmz_lock_map(zmd);
> again:
> @@ -2026,7 +2067,7 @@ struct dm_zone *dmz_get_chunk_buffer(struct
> dmz_metadata *zmd,
> goto out;
>
> /* Allocate a random zone */
> - bzone = dmz_alloc_zone(zmd, DMZ_ALLOC_RND);
> + bzone = dmz_alloc_zone(zmd, alloc_flags);
> if (!bzone) {
> if (dmz_dev_is_dying(zmd)) {
> bzone = ERR_PTR(-EIO);
> @@ -2043,7 +2084,10 @@ struct dm_zone *dmz_get_chunk_buffer(struct
> dmz_metadata *zmd,
> bzone->chunk = dzone->chunk;
> bzone->bzone = dzone;
> dzone->bzone = bzone;
> - list_add_tail(&bzone->link, &zmd->map_rnd_list);
> + if (alloc_flags == DMZ_ALLOC_CACHE)
> + list_add_tail(&bzone->link, &zmd->map_cache_list);
> + else
> + list_add_tail(&bzone->link, &zmd->map_rnd_list);
> out:
> dmz_unlock_map(zmd);
>
> @@ -2059,31 +2103,53 @@ struct dm_zone *dmz_alloc_zone(struct dmz_metadata
> *zmd, unsigned long flags)
> struct list_head *list;
> struct dm_zone *zone;
>
> - if (flags & DMZ_ALLOC_RND)
> + switch (flags) {
> + case DMZ_ALLOC_CACHE:
> + list = &zmd->unmap_cache_list;
> + break;
> + case DMZ_ALLOC_RND:
> list = &zmd->unmap_rnd_list;
> - else
> - list = &zmd->unmap_seq_list;
> + break;
> + default:
> + if (zmd->nr_cache)> + list =
> &zmd->unmap_rnd_list;
> + else
> + list = &zmd->unmap_seq_list;
> + break;
> + }
> again:
> if (list_empty(list)) {
> /*
> - * No free zone: if this is for reclaim, allow using the
> - * reserved sequential zones.
> + * No free zone: return NULL if this is for not reclaim.
s/for not reclaim/not for reclaim
> */
> - if (!(flags & DMZ_ALLOC_RECLAIM) ||
> - list_empty(&zmd->reserved_seq_zones_list))
> + if (!(flags & DMZ_ALLOC_RECLAIM))
> return NULL;
> -
> - zone = list_first_entry(&zmd->reserved_seq_zones_list,
> - struct dm_zone, link);
> - list_del_init(&zone->link);
> - atomic_dec(&zmd->nr_reserved_seq_zones);
> + /*
> + * Use sequential write zones if we started off with random
> + * zones and the list is empty
> + */
> + if (list == &zmd->unmap_rnd_list) {
> + list = &zmd->unmap_seq_list;
> + goto again;
> + }
> + /*
> + * Fallback to the reserved sequential zones
> + */
> + zone = list_first_entry_or_null(&zmd->reserved_seq_zones_list,
> + struct dm_zone, link);
> + if (zone) {
> + list_del_init(&zone->link);
> + atomic_dec(&zmd->nr_reserved_seq_zones);
> + }
> return zone;
> }
>
> zone = list_first_entry(list, struct dm_zone, link);
> list_del_init(&zone->link);
>
> - if (dmz_is_rnd(zone))
> + if (dmz_is_cache(zone))
> + atomic_dec(&zmd->unmap_nr_cache);
> + else if (dmz_is_rnd(zone))
> atomic_dec(&zmd->unmap_nr_rnd);
> else
> atomic_dec(&zmd->unmap_nr_seq);
> @@ -2114,7 +2180,10 @@ void dmz_free_zone(struct dmz_metadata *zmd, struct
> dm_zone *zone)
> dmz_reset_zone(zmd, zone);
>
> /* Return the zone to its type unmap list */
> - if (dmz_is_rnd(zone)) {
> + if (dmz_is_cache(zone)) {
> + list_add_tail(&zone->link, &zmd->unmap_cache_list);
> + atomic_inc(&zmd->unmap_nr_cache);
> + } else if (dmz_is_rnd(zone)) {
> list_add_tail(&zone->link, &zmd->unmap_rnd_list);
> atomic_inc(&zmd->unmap_nr_rnd);
> } else if (atomic_read(&zmd->nr_reserved_seq_zones) <
> @@ -2140,7 +2209,9 @@ void dmz_map_zone(struct dmz_metadata *zmd, struct
> dm_zone *dzone,
> dmz_set_chunk_mapping(zmd, chunk, dzone->id,
> DMZ_MAP_UNMAPPED);
> dzone->chunk = chunk;
> - if (dmz_is_rnd(dzone))
> + if (dmz_is_cache(dzone))
> + list_add_tail(&dzone->link, &zmd->map_cache_list);
> + else if (dmz_is_rnd(dzone))
> list_add_tail(&dzone->link, &zmd->map_rnd_list);
> else
> list_add_tail(&dzone->link, &zmd->map_seq_list);
> @@ -2714,6 +2785,10 @@ int dmz_ctr_metadata(struct dmz_dev *dev, int num_dev,
> INIT_LIST_HEAD(&zmd->unmap_rnd_list);
> INIT_LIST_HEAD(&zmd->map_rnd_list);
>
> + atomic_set(&zmd->unmap_nr_cache, 0);
> + INIT_LIST_HEAD(&zmd->unmap_cache_list);
> + INIT_LIST_HEAD(&zmd->map_cache_list);
> +
> atomic_set(&zmd->unmap_nr_seq, 0);
> INIT_LIST_HEAD(&zmd->unmap_seq_list);
> INIT_LIST_HEAD(&zmd->map_seq_list);
> @@ -2736,7 +2811,7 @@ int dmz_ctr_metadata(struct dmz_dev *dev, int num_dev,
> /* Set metadata zones starting from sb_zone */
> for (i = 0; i < zmd->nr_meta_zones << 1; i++) {
> zone = dmz_get(zmd, zmd->sb[0].zone->id + i);
> - if (!dmz_is_rnd(zone)) {
> + if (!dmz_is_rnd(zone) && !dmz_is_cache(zone)) {
> dmz_zmd_err(zmd,
> "metadata zone %d is not random", i);
> ret = -ENXIO;
> @@ -2788,6 +2863,8 @@ int dmz_ctr_metadata(struct dmz_dev *dev, int num_dev,
> zmd->nr_meta_zones * 2);
> dmz_zmd_debug(zmd, " %u data zones for %u chunks",
> zmd->nr_data_zones, zmd->nr_chunks);
> + dmz_zmd_debug(zmd, " %u cache zones (%u unmapped)",
> + zmd->nr_cache, atomic_read(&zmd->unmap_nr_cache));
> dmz_zmd_debug(zmd, " %u random zones (%u unmapped)",
> zmd->nr_rnd, atomic_read(&zmd->unmap_nr_rnd));
> dmz_zmd_debug(zmd, " %u sequential zones (%u unmapped)",
> diff --git a/drivers/md/dm-zoned-reclaim.c b/drivers/md/dm-zoned-reclaim.c
> index 39ea0d5d4706..6004cf71a000 100644
> --- a/drivers/md/dm-zoned-reclaim.c
> +++ b/drivers/md/dm-zoned-reclaim.c
> @@ -43,13 +43,13 @@ enum {
> * Percentage of unmapped (free) random zones below which reclaim starts
> * even if the target is busy.
> */
> -#define DMZ_RECLAIM_LOW_UNMAP_RND 30
> +#define DMZ_RECLAIM_LOW_UNMAP_ZONES 30
>
> /*
> * Percentage of unmapped (free) random zones above which reclaim will
> * stop if the target is busy.
> */
> -#define DMZ_RECLAIM_HIGH_UNMAP_RND 50
> +#define DMZ_RECLAIM_HIGH_UNMAP_ZONES 50
>
> /*
> * Align a sequential zone write pointer to chunk_block.
> @@ -289,9 +289,11 @@ static int dmz_reclaim_rnd_data(struct dmz_reclaim *zrc,
> struct dm_zone *dzone)
> if (!szone)
> return -ENOSPC;
>
> - DMDEBUG("(%s): Chunk %u, move rnd zone %u (weight %u) to seq zone %u",
> - dmz_metadata_label(zmd),
> - chunk, dzone->id, dmz_weight(dzone), szone->id);
> + DMDEBUG("(%s): Chunk %u, move %s zone %u (weight %u) to %s zone %u",
> + dmz_metadata_label(zmd), chunk,
> + dmz_is_cache(dzone) ? "cache" : "rnd",
> + dzone->id, dmz_weight(dzone),
> + dmz_is_rnd(szone) ? "rnd" : "seq", szone->id);
>
> /* Flush the random data zone into the sequential zone */
> ret = dmz_reclaim_copy(zrc, dzone, szone);
> @@ -358,7 +360,7 @@ static int dmz_do_reclaim(struct dmz_reclaim *zrc)
>
> start = jiffies;
> dev = dmz_zone_to_dev(zmd, dzone);
> - if (dmz_is_rnd(dzone)) {
> + if (dmz_is_cache(dzone) || dmz_is_rnd(dzone)) {
> if (!dmz_weight(dzone)) {
> /* Empty zone */
> dmz_reclaim_empty(zrc, dzone);
> @@ -424,29 +426,41 @@ static inline int dmz_target_idle(struct dmz_reclaim
> *zrc)
> return time_is_before_jiffies(zrc->atime + DMZ_IDLE_PERIOD);
> }
>
> -/*
> - * Test if reclaim is necessary.
> - */
> -static bool dmz_should_reclaim(struct dmz_reclaim *zrc)
> +static unsigned int dmz_reclaim_percentage(struct dmz_reclaim *zrc)
> {
> struct dmz_metadata *zmd = zrc->metadata;
> + unsigned int nr_cache = dmz_nr_cache_zones(zmd);
> unsigned int nr_rnd = dmz_nr_rnd_zones(zmd);
> - unsigned int nr_unmap_rnd = dmz_nr_unmap_rnd_zones(zmd);
> - unsigned int p_unmap_rnd = nr_unmap_rnd * 100 / nr_rnd;
> + unsigned int nr_unmap, nr_zones;
>
> + if (nr_cache) {
> + nr_zones = nr_cache;
> + nr_unmap = dmz_nr_unmap_cache_zones(zmd);
> + } else {
> + nr_zones = nr_rnd;
> + nr_unmap = dmz_nr_unmap_rnd_zones(zmd);
> + }
> + return nr_unmap * 100 / nr_zones;
> +}
> +
> +/*
> + * Test if reclaim is necessary.
> + */
> +static bool dmz_should_reclaim(struct dmz_reclaim *zrc, unsigned int p_unmap)
> +{
> /* Reclaim when idle */
> - if (dmz_target_idle(zrc) && nr_unmap_rnd < nr_rnd)
> + if (dmz_target_idle(zrc) && p_unmap < 100)
> return true;
>
> - /* If there are still plenty of random zones, do not reclaim */
> - if (p_unmap_rnd >= DMZ_RECLAIM_HIGH_UNMAP_RND)
> + /* If there are still plenty of cache zones, do not reclaim */
> + if (p_unmap >= DMZ_RECLAIM_HIGH_UNMAP_ZONES)
> return false;
>
> /*
> - * If the percentage of unmapped random zones is low,
> + * If the percentage of unmapped cache zones is low,
> * reclaim even if the target is busy.
> */
> - return p_unmap_rnd <= DMZ_RECLAIM_LOW_UNMAP_RND;
> + return p_unmap <= DMZ_RECLAIM_LOW_UNMAP_ZONES;
> }
>
> /*
> @@ -456,14 +470,14 @@ static void dmz_reclaim_work(struct work_struct *work)
> {
> struct dmz_reclaim *zrc = container_of(work, struct dmz_reclaim,
> work.work);
> struct dmz_metadata *zmd = zrc->metadata;
> - unsigned int nr_rnd, nr_unmap_rnd;
> - unsigned int p_unmap_rnd;
> + unsigned int p_unmap;
> int ret;
>
> if (dmz_dev_is_dying(zmd))
> return;
>
> - if (!dmz_should_reclaim(zrc)) {
> + p_unmap = dmz_reclaim_percentage(zrc);
> + if (!dmz_should_reclaim(zrc, p_unmap)) {
> mod_delayed_work(zrc->wq, &zrc->work, DMZ_IDLE_PERIOD);
> return;
> }
> @@ -474,22 +488,20 @@ static void dmz_reclaim_work(struct work_struct *work)
> * and slower if there are still some free random zones to avoid
> * as much as possible to negatively impact the user workload.
> */
> - nr_rnd = dmz_nr_rnd_zones(zmd);
> - nr_unmap_rnd = dmz_nr_unmap_rnd_zones(zmd);
> - p_unmap_rnd = nr_unmap_rnd * 100 / nr_rnd;
> - if (dmz_target_idle(zrc) || p_unmap_rnd < DMZ_RECLAIM_LOW_UNMAP_RND /
> 2) {
> + if (dmz_target_idle(zrc) || p_unmap < DMZ_RECLAIM_LOW_UNMAP_ZONES / 2) {
> /* Idle or very low percentage: go fast */
> zrc->kc_throttle.throttle = 100;
> } else {
> /* Busy but we still have some random zone: throttle */
> - zrc->kc_throttle.throttle = min(75U, 100U - p_unmap_rnd / 2);
> + zrc->kc_throttle.throttle = min(75U, 100U - p_unmap / 2);
> }
>
> - DMDEBUG("(%s): Reclaim (%u): %s, %u%% free rnd zones (%u/%u)",
> + DMDEBUG("(%s): Reclaim (%u): %s, %u%% free cache zones (%u/%u)",
> dmz_metadata_label(zmd),
> zrc->kc_throttle.throttle,
> (dmz_target_idle(zrc) ? "Idle" : "Busy"),
> - p_unmap_rnd, nr_unmap_rnd, nr_rnd);
> + p_unmap, dmz_nr_unmap_cache_zones(zmd),
> + dmz_nr_cache_zones(zmd));
>
> ret = dmz_do_reclaim(zrc);
> if (ret) {
> @@ -587,7 +599,9 @@ void dmz_reclaim_bio_acc(struct dmz_reclaim *zrc)
> */
> void dmz_schedule_reclaim(struct dmz_reclaim *zrc)
> {
> - if (dmz_should_reclaim(zrc))
> + unsigned int p_unmap = dmz_reclaim_percentage(zrc);
> +
> + if (dmz_should_reclaim(zrc, p_unmap))
> mod_delayed_work(zrc->wq, &zrc->work, 0);
> }
>
> diff --git a/drivers/md/dm-zoned-target.c b/drivers/md/dm-zoned-target.c
> index ea43f6892ced..8999de07cddb 100644
> --- a/drivers/md/dm-zoned-target.c
> +++ b/drivers/md/dm-zoned-target.c
> @@ -190,7 +190,8 @@ static int dmz_handle_read(struct dmz_target *dmz, struct
> dm_zone *zone,
> DMDEBUG("(%s): READ chunk %llu -> %s zone %u, block %llu, %u blocks",
> dmz_metadata_label(zmd),
> (unsigned long long)dmz_bio_chunk(zmd, bio),
> - (dmz_is_rnd(zone) ? "RND" : "SEQ"),
> + (dmz_is_rnd(zone) ? "RND" :
> + (dmz_is_cache(zone) ? "CACHE" : "SEQ")),
> zone->id,
> (unsigned long long)chunk_block, nr_blocks);
>
> @@ -198,7 +199,8 @@ static int dmz_handle_read(struct dmz_target *dmz, struct
> dm_zone *zone,
> bzone = zone->bzone;
> while (chunk_block < end_block) {
> nr_blocks = 0;
> - if (dmz_is_rnd(zone) || chunk_block < zone->wp_block) {
> + if (dmz_is_rnd(zone) || dmz_is_cache(zone) ||
> + chunk_block < zone->wp_block) {
> /* Test block validity in the data zone */
> ret = dmz_block_valid(zmd, zone, chunk_block);
> if (ret < 0)
> @@ -331,11 +333,13 @@ static int dmz_handle_write(struct dmz_target *dmz,
> struct dm_zone *zone,
> DMDEBUG("(%s): WRITE chunk %llu -> %s zone %u, block %llu, %u blocks",
> dmz_metadata_label(zmd),
> (unsigned long long)dmz_bio_chunk(zmd, bio),
> - (dmz_is_rnd(zone) ? "RND" : "SEQ"),
> + (dmz_is_rnd(zone) ? "RND" :
> + (dmz_is_cache(zone) ? "CACHE" : "SEQ")),
> zone->id,
> (unsigned long long)chunk_block, nr_blocks);
>
> - if (dmz_is_rnd(zone) || chunk_block == zone->wp_block) {
> + if (dmz_is_rnd(zone) || dmz_is_cache(zone) ||
> + chunk_block == zone->wp_block) {
> /*
> * zone is a random zone or it is a sequential zone
> * and the BIO is aligned to the zone write pointer:
> @@ -381,7 +385,8 @@ static int dmz_handle_discard(struct dmz_target *dmz,
> struct dm_zone *zone,
> * Invalidate blocks in the data zone and its
> * buffer zone if one is mapped.
> */
> - if (dmz_is_rnd(zone) || chunk_block < zone->wp_block)
> + if (dmz_is_rnd(zone) || dmz_is_cache(zone) ||
> + chunk_block < zone->wp_block)
> ret = dmz_invalidate_blocks(zmd, zone, chunk_block, nr_blocks);
> if (ret == 0 && zone->bzone)
> ret = dmz_invalidate_blocks(zmd, zone->bzone,
> @@ -1064,8 +1069,10 @@ static void dmz_status(struct dm_target *ti,
> status_type_t type,
>
> switch (type) {
> case STATUSTYPE_INFO:
> - DMEMIT("%u zones %u/%u random %u/%u sequential",
> + DMEMIT("%u zones %u/%u cache %u/%u random %u/%u sequential",
> dmz_nr_zones(dmz->metadata),
> + dmz_nr_unmap_cache_zones(dmz->metadata),
> + dmz_nr_cache_zones(dmz->metadata),
> dmz_nr_unmap_rnd_zones(dmz->metadata),
> dmz_nr_rnd_zones(dmz->metadata),
> dmz_nr_unmap_seq_zones(dmz->metadata),
> diff --git a/drivers/md/dm-zoned.h b/drivers/md/dm-zoned.h
> index 4971a765be55..b1bdfa3c957a 100644
> --- a/drivers/md/dm-zoned.h
> +++ b/drivers/md/dm-zoned.h
> @@ -111,6 +111,7 @@ struct dm_zone {
> */
> enum {
> /* Zone write type */
> + DMZ_CACHE,
> DMZ_RND,
> DMZ_SEQ,
>
> @@ -131,6 +132,7 @@ enum {
> /*
> * Zone data accessors.
> */
> +#define dmz_is_cache(z) test_bit(DMZ_CACHE, &(z)->flags)
> #define dmz_is_rnd(z) test_bit(DMZ_RND, &(z)->flags)
> #define dmz_is_seq(z) test_bit(DMZ_SEQ, &(z)->flags)
> #define dmz_is_empty(z) ((z)->wp_block == 0)
> @@ -189,7 +191,8 @@ bool dmz_check_dev(struct dmz_metadata *zmd);
> bool dmz_dev_is_dying(struct dmz_metadata *zmd);
>
> #define DMZ_ALLOC_RND 0x01
> -#define DMZ_ALLOC_RECLAIM 0x02
> +#define DMZ_ALLOC_CACHE 0x02
> +#define DMZ_ALLOC_RECLAIM 0x04
>
> struct dm_zone *dmz_alloc_zone(struct dmz_metadata *zmd, unsigned long
> flags);
> void dmz_free_zone(struct dmz_metadata *zmd, struct dm_zone *zone);
> @@ -198,6 +201,8 @@ void dmz_map_zone(struct dmz_metadata *zmd, struct
> dm_zone *zone,
> unsigned int chunk);
> void dmz_unmap_zone(struct dmz_metadata *zmd, struct dm_zone *zone);
> unsigned int dmz_nr_zones(struct dmz_metadata *zmd);
> +unsigned int dmz_nr_cache_zones(struct dmz_metadata *zmd);
> +unsigned int dmz_nr_unmap_cache_zones(struct dmz_metadata *zmd);
> unsigned int dmz_nr_rnd_zones(struct dmz_metadata *zmd);
> unsigned int dmz_nr_unmap_rnd_zones(struct dmz_metadata *zmd);
> unsigned int dmz_nr_seq_zones(struct dmz_metadata *zmd);
>
Apart from the nits above, all look good. I am running this right now and it is
running at SMR drive speed ! Awesome ! Will send a plot once the run is over.
Cheers.
--
Damien Le Moal
Western Digital Research
--
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