From e71aa913e26543768d5acaef50abe14913c6c496 Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Wed, 27 Oct 2021 13:21:09 +0100 Subject: [PATCH] block: kill DIO_MULTI_BIO Now __blkdev_direct_IO() serves only multi-bio I/O, thus remove not used anymore single bio refcounting optimisations. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/88eb488aae9ed4852a30f3a7132f296f56e43b80.1635337135.git.asml.silence@gmail.com Signed-off-by: Jens Axboe --- block/fops.c | 33 ++++++++++++--------------------- 1 file changed, 12 insertions(+), 21 deletions(-) diff --git a/block/fops.c b/block/fops.c index 983e993..8594852 100644 --- a/block/fops.c +++ b/block/fops.c @@ -124,9 +124,8 @@ out: } enum { - DIO_MULTI_BIO = 1, - DIO_SHOULD_DIRTY = 2, - DIO_IS_SYNC = 4, + DIO_SHOULD_DIRTY = 1, + DIO_IS_SYNC = 2, }; struct blkdev_dio { @@ -150,7 +149,7 @@ static void blkdev_bio_end_io(struct bio *bio) if (bio->bi_status && !dio->bio.bi_status) dio->bio.bi_status = bio->bi_status; - if (!(dio->flags & DIO_MULTI_BIO) || atomic_dec_and_test(&dio->ref)) { + if (atomic_dec_and_test(&dio->ref)) { if (!(dio->flags & DIO_IS_SYNC)) { struct kiocb *iocb = dio->iocb; ssize_t ret; @@ -165,8 +164,7 @@ static void blkdev_bio_end_io(struct bio *bio) } dio->iocb->ki_complete(iocb, ret, 0); - if (dio->flags & DIO_MULTI_BIO) - bio_put(&dio->bio); + bio_put(&dio->bio); } else { struct task_struct *waiter = dio->waiter; @@ -201,11 +199,17 @@ static ssize_t __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, bio = bio_alloc_kiocb(iocb, nr_pages, &blkdev_dio_pool); dio = container_of(bio, struct blkdev_dio, bio); + atomic_set(&dio->ref, 1); + /* + * Grab an extra reference to ensure the dio structure which is embedded + * into the first bio stays around. + */ + bio_get(bio); + is_sync = is_sync_kiocb(iocb); if (is_sync) { dio->flags = DIO_IS_SYNC; dio->waiter = current; - bio_get(bio); } else { dio->flags = 0; dio->iocb = iocb; @@ -251,20 +255,7 @@ static ssize_t __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, submit_bio(bio); break; } - if (!(dio->flags & DIO_MULTI_BIO)) { - /* - * AIO needs an extra reference to ensure the dio - * structure which is embedded into the first bio - * stays around. - */ - if (!is_sync) - bio_get(bio); - dio->flags |= DIO_MULTI_BIO; - atomic_set(&dio->ref, 2); - } else { - atomic_inc(&dio->ref); - } - + atomic_inc(&dio->ref); submit_bio(bio); bio = bio_alloc(GFP_KERNEL, nr_pages); } -- 2.7.4