From 1933192a91be0a570663a3c6310c46e4ce3b2baa Mon Sep 17 00:00:00 2001 From: Damien Le Moal Date: Fri, 7 Jun 2024 09:21:26 +0900 Subject: [PATCH] block: Optimize disk zone resource cleanup For zoned block devices using zone write plugging, an rcu_barrier() call is needed in disk_free_zone_resources() to synchronize freeing of zone write plugs and the destrution of the mempool used to allocate the plugs. The barrier call does slow down a little teardown of zoned block devices but should not affect teardown of regular block devices or zoned block devices that do not use zone write plugging (e.g. zoned DM devices that do not require zone append emulation). Modify disk_free_zone_resources() to return early if we do not have a mempool to start with, that is, if the device does not use zone write plugging. This avoids the costly rcu_barrier() and speeds up disk teardown. Reported-by: Mikulas Patocka Fixes: dd291d77cc90 ("block: Introduce zone write plugging") Signed-off-by: Damien Le Moal Reviewed-by: Christoph Hellwig Tested-by: Mikulas Patocka Reviewed-by: Niklas Cassel Link: https://lore.kernel.org/r/20240607002126.104227-1-dlemoal@kernel.org Signed-off-by: Jens Axboe --- block/blk-zoned.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/block/blk-zoned.c b/block/blk-zoned.c index 52abebf56027..08d7dfe8bd93 100644 --- a/block/blk-zoned.c +++ b/block/blk-zoned.c @@ -1552,6 +1552,9 @@ static void disk_destroy_zone_wplugs_hash_table(struct gendisk *disk) void disk_free_zone_resources(struct gendisk *disk) { + if (!disk->zone_wplugs_pool) + return; + cancel_work_sync(&disk->zone_wplugs_work); if (disk->zone_wplugs_wq) {