| Message ID | 20230822191822.337080-2-bvanassche@acm.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Improve write performance for zoned UFS devices | expand |
On 8/22/23 21:16, Bart Van Assche wrote: > Many but not all storage controllers require serialization of zoned writes. > Introduce two new request queue limit member variables related to write > serialization. 'driver_preserves_write_order' allows block drivers to > indicate that the order of write commands is preserved and hence that > serialization of writes per zone is not required. 'use_zone_write_lock' is > set by disk_set_zoned() if and only if the block device has zones and if > the block driver does not preserve the order of write requests. > > Reviewed-by: Damien Le Moal <dlemoal@kernel.org> > Cc: Christoph Hellwig <hch@lst.de> > Cc: Ming Lei <ming.lei@redhat.com> > Signed-off-by: Bart Van Assche <bvanassche@acm.org> > --- > block/blk-settings.c | 15 +++++++++++++++ > block/blk-zoned.c | 1 + > include/linux/blkdev.h | 10 ++++++++++ > 3 files changed, 26 insertions(+) > Reviewed-by: Hannes Reinecke <hare@suse.de> Cheers, Hannes
On 23/08/22 12:16PM, Bart Van Assche wrote: >Many but not all storage controllers require serialization of zoned writes. >Introduce two new request queue limit member variables related to write >serialization. 'driver_preserves_write_order' allows block drivers to >indicate that the order of write commands is preserved and hence that >serialization of writes per zone is not required. 'use_zone_write_lock' is >set by disk_set_zoned() if and only if the block device has zones and if >the block driver does not preserve the order of write requests. > >Reviewed-by: Damien Le Moal <dlemoal@kernel.org> >Cc: Christoph Hellwig <hch@lst.de> >Cc: Ming Lei <ming.lei@redhat.com> >Signed-off-by: Bart Van Assche <bvanassche@acm.org> >--- Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
diff --git a/block/blk-settings.c b/block/blk-settings.c index 0046b447268f..4c776c08f190 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -56,6 +56,8 @@ void blk_set_default_limits(struct queue_limits *lim) lim->alignment_offset = 0; lim->io_opt = 0; lim->misaligned = 0; + lim->driver_preserves_write_order = false; + lim->use_zone_write_lock = false; lim->zoned = BLK_ZONED_NONE; lim->zone_write_granularity = 0; lim->dma_alignment = 511; @@ -82,6 +84,8 @@ void blk_set_stacking_limits(struct queue_limits *lim) lim->max_dev_sectors = UINT_MAX; lim->max_write_zeroes_sectors = UINT_MAX; lim->max_zone_append_sectors = UINT_MAX; + /* Request-based stacking drivers do not reorder requests. */ + lim->driver_preserves_write_order = true; } EXPORT_SYMBOL(blk_set_stacking_limits); @@ -685,6 +689,10 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, b->max_secure_erase_sectors); t->zone_write_granularity = max(t->zone_write_granularity, b->zone_write_granularity); + t->driver_preserves_write_order = t->driver_preserves_write_order && + b->driver_preserves_write_order; + t->use_zone_write_lock = t->use_zone_write_lock || + b->use_zone_write_lock; t->zoned = max(t->zoned, b->zoned); return ret; } @@ -949,6 +957,13 @@ void disk_set_zoned(struct gendisk *disk, enum blk_zoned_model model) } q->limits.zoned = model; + /* + * Use the zone write lock only for zoned block devices and only if + * the block driver does not preserve the order of write commands. + */ + q->limits.use_zone_write_lock = model != BLK_ZONED_NONE && + !q->limits.driver_preserves_write_order; + if (model != BLK_ZONED_NONE) { /* * Set the zone write granularity to the device logical block diff --git a/block/blk-zoned.c b/block/blk-zoned.c index 619ee41a51cc..112620985bff 100644 --- a/block/blk-zoned.c +++ b/block/blk-zoned.c @@ -631,6 +631,7 @@ void disk_clear_zone_settings(struct gendisk *disk) q->limits.chunk_sectors = 0; q->limits.zone_write_granularity = 0; q->limits.max_zone_append_sectors = 0; + q->limits.use_zone_write_lock = false; blk_mq_unfreeze_queue(q); } diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index c1421da8d45e..38a1a71b2bcc 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -316,6 +316,16 @@ struct queue_limits { unsigned char misaligned; unsigned char discard_misaligned; unsigned char raid_partial_stripes_expensive; + /* + * Whether or not the block driver preserves the order of write + * requests. Set by the block driver. + */ + bool driver_preserves_write_order; + /* + * Whether or not zone write locking should be used. Set by + * disk_set_zoned(). + */ + bool use_zone_write_lock; enum blk_zoned_model zoned; /*