commit 47fe1c3064c6bc1bfa3c032ff78e603e5dd6e5bc upstream.

The scsi driver function sd_read_block_characteristics() always calls blk_queue_set_zoned() to set a disk zoned model correctly, in case the device model changed. This is done even for regular disks to set the zoned model to BLK_ZONED_NONE and free any zone related resources if the drive previously was zoned.

This behavior significantly impact the time it takes to revalidate disks on a large system as the call to blk_queue_clear_zone_settings() done from blk_queue_set_zoned() for the BLK_ZONED_NONE case results in the device request queued to be frozen, even if there are no zone resources to free.

Avoid this overhead for non-zoned devices by not calling blk_queue_clear_zone_settings() in blk_queue_set_zoned() if the device model was already set to BLK_ZONED_NONE, which is always the case for regular devices.

Reported by: Brian Bunker brian@purestorage.com Fixes: 508aebb80527 ("block: introduce blk_queue_clear_zone_settings()") Cc: stable@vger.kernel.org Signed-off-by: Damien Le Moal dlemoal@kernel.org Reviewed-by: Ming Lei ming.lei@redhat.com Link: https://lore.kernel.org/r/20230529073237.1339862-1-dlemoal@kernel.org Signed-off-by: Jens Axboe axboe@kernel.dk --- block/blk-settings.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/block/blk-settings.c b/block/blk-settings.c index b880c70e22e4..73a80895e3ae 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -875,6 +875,7 @@ static bool disk_has_partitions(struct gendisk *disk) void blk_queue_set_zoned(struct gendisk *disk, enum blk_zoned_model model) { struct request_queue *q = disk->queue; + unsigned int old_model = q->limits.zoned;

switch (model) { case BLK_ZONED_HM: @@ -912,7 +913,7 @@ void blk_queue_set_zoned(struct gendisk *disk, enum blk_zoned_model model) */ blk_queue_zone_write_granularity(q, queue_logical_block_size(q)); - } else { + } else if (old_model != BLK_ZONED_NONE) { blk_queue_clear_zone_settings(q); } }

On 6/6/23 04:52, gregkh@linuxfoundation.org wrote:

The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x 47fe1c3064c6bc1bfa3c032ff78e603e5dd6e5bc # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2023060549-smolder-human-a813@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Hi Greg,

I sent a backport using the above command. Thanks !

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 47fe1c3064c6bc1bfa3c032ff78e603e5dd6e5bc Mon Sep 17 00:00:00 2001 From: Damien Le Moal dlemoal@kernel.org Date: Mon, 29 May 2023 16:32:37 +0900 Subject: [PATCH] block: fix revalidate performance regression

The scsi driver function sd_read_block_characteristics() always calls disk_set_zoned() to a disk zoned model correctly, in case the device model changed. This is done even for regular disks to set the zoned model to BLK_ZONED_NONE and free any zone related resources if the drive previously was zoned.

This behavior significantly impact the time it takes to revalidate disks on a large system as the call to disk_clear_zone_settings() done from disk_set_zoned() for the BLK_ZONED_NONE case results in the device request queued to be frozen, even if there are no zone resources to free.

Avoid this overhead for non-zoned devices by not calling disk_clear_zone_settings() in disk_set_zoned() if the device model was already set to BLK_ZONED_NONE, which is always the case for regular devices.

Reported by: Brian Bunker brian@purestorage.com

Fixes: 508aebb80527 ("block: introduce blk_queue_clear_zone_settings()") Cc: stable@vger.kernel.org Signed-off-by: Damien Le Moal dlemoal@kernel.org Reviewed-by: Ming Lei ming.lei@redhat.com Link: https://lore.kernel.org/r/20230529073237.1339862-1-dlemoal@kernel.org Signed-off-by: Jens Axboe axboe@kernel.dk

diff --git a/block/blk-settings.c b/block/blk-settings.c index 896b4654ab00..4dd59059b788 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -915,6 +915,7 @@ static bool disk_has_partitions(struct gendisk *disk) void disk_set_zoned(struct gendisk *disk, enum blk_zoned_model model) { struct request_queue *q = disk->queue;

• unsigned int old_model = q->limits.zoned;

switch (model) { case BLK_ZONED_HM: @@ -952,7 +953,7 @@ void disk_set_zoned(struct gendisk *disk, enum blk_zoned_model model) */ blk_queue_zone_write_granularity(q, queue_logical_block_size(q));

• } else {

• } else if (old_model != BLK_ZONED_NONE) { disk_clear_zone_settings(disk); }

}