The .bd_inode field of block_device is used in IO fast path of
blkdev_write_iter() and blkdev_llseek(), so it is more efficient to keep
it into the 1st cacheline.
.bd_openers is only touched in open()/close(), and .bd_size_lock is only
for updating bdev capacity, which is in slow path too.
So swap .bd_inode layout with .bd_openers & .bd_size_lock to move
.bd_inode into the 1st cache line.
Cc: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231128123027.971610-2-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
bool bd_write_holder;
bool bd_has_submit_bio;
dev_t bd_dev;
+ struct inode *bd_inode; /* will die */
+
atomic_t bd_openers;
spinlock_t bd_size_lock; /* for bd_inode->i_size updates */
- struct inode * bd_inode; /* will die */
void * bd_claiming;
void * bd_holder;
const struct blk_holder_ops *bd_holder_ops;