From 9f4107b07b17b5ee68af680150f91227bea2df6f Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Fri, 14 Apr 2023 07:32:02 -0600 Subject: block: store bdev->bd_disk->fops->submit_bio state in bdev We have a long chain of memory dereferencing just to whether or not this disk has a special submit_bio helper. As that's not necessarily the common case, add a bd_has_submit_bio state in the bdev to avoid traversing this memory dependency chain if we don't need to. Signed-off-by: Jens Axboe --- block/bdev.c | 1 + block/blk-core.c | 8 ++++---- block/genhd.c | 3 +++ include/linux/blk_types.h | 1 + 4 files changed, 9 insertions(+), 4 deletions(-) diff --git a/block/bdev.c b/block/bdev.c index 1795c7d4b99e..850852fe4b78 100644 --- a/block/bdev.c +++ b/block/bdev.c @@ -419,6 +419,7 @@ struct block_device *bdev_alloc(struct gendisk *disk, u8 partno) bdev->bd_inode = inode; bdev->bd_queue = disk->queue; bdev->bd_stats = alloc_percpu(struct disk_stats); + bdev->bd_has_submit_bio = false; if (!bdev->bd_stats) { iput(inode); return NULL; diff --git a/block/blk-core.c b/block/blk-core.c index 269765d16cfd..06bdb352568c 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -587,14 +587,14 @@ static inline blk_status_t blk_check_zone_append(struct request_queue *q, static void __submit_bio(struct bio *bio) { - struct gendisk *disk = bio->bi_bdev->bd_disk; - if (unlikely(!blk_crypto_bio_prep(&bio))) return; - if (!disk->fops->submit_bio) { + if (!bio->bi_bdev->bd_has_submit_bio) { blk_mq_submit_bio(bio); } else if (likely(bio_queue_enter(bio) == 0)) { + struct gendisk *disk = bio->bi_bdev->bd_disk; + disk->fops->submit_bio(bio); blk_queue_exit(disk->queue); } @@ -698,7 +698,7 @@ void submit_bio_noacct_nocheck(struct bio *bio) */ if (current->bio_list) bio_list_add(¤t->bio_list[0], bio); - else if (!bio->bi_bdev->bd_disk->fops->submit_bio) + else if (!bio->bi_bdev->bd_has_submit_bio) __submit_bio_noacct_mq(bio); else __submit_bio_noacct(bio); diff --git a/block/genhd.c b/block/genhd.c index 02d9cfb9e077..cadcb472dfc3 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -420,6 +420,9 @@ int __must_check device_add_disk(struct device *parent, struct gendisk *disk, */ elevator_init_mq(disk->queue); + /* Mark bdev as having a submit_bio, if needed */ + disk->part0->bd_has_submit_bio = disk->fops->submit_bio != NULL; + /* * If the driver provides an explicit major number it also must provide * the number of minors numbers supported, and those will be used to diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index c1da616fadae..3e8e9a97de46 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -47,6 +47,7 @@ struct block_device { bool bd_read_only; /* read-only policy */ u8 bd_partno; bool bd_write_holder; + bool bd_has_submit_bio; dev_t bd_dev; atomic_t bd_openers; spinlock_t bd_size_lock; /* for bd_inode->i_size updates */ -- cgit v1.2.3-58-ga151