| Message ID | 20220720142456.1414262-2-hch@lst.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/5] block: move ->bio_split to the gendisk | expand |
On 7/20/22 23:24, Christoph Hellwig wrote: > Only non-passthrough requests are split by the block layer and use the > ->bio_split bio_set. Move it from the request_queue to the gendisk. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > block/blk-core.c | 9 +-------- > block/blk-merge.c | 20 ++++++++++---------- > block/blk-sysfs.c | 2 -- > block/genhd.c | 9 ++++++++- > drivers/md/dm.c | 2 +- > include/linux/blkdev.h | 3 ++- > 6 files changed, 22 insertions(+), 23 deletions(-) > > diff --git a/block/blk-core.c b/block/blk-core.c > index 123468b9d2e43..59f13d011949d 100644 > --- a/block/blk-core.c > +++ b/block/blk-core.c > @@ -377,7 +377,6 @@ static void blk_timeout_work(struct work_struct *work) > struct request_queue *blk_alloc_queue(int node_id, bool alloc_srcu) > { > struct request_queue *q; > - int ret; > > q = kmem_cache_alloc_node(blk_get_queue_kmem_cache(alloc_srcu), > GFP_KERNEL | __GFP_ZERO, node_id); > @@ -396,13 +395,9 @@ struct request_queue *blk_alloc_queue(int node_id, bool alloc_srcu) > if (q->id < 0) > goto fail_srcu; > > - ret = bioset_init(&q->bio_split, BIO_POOL_SIZE, 0, 0); > - if (ret) > - goto fail_id; > - > q->stats = blk_alloc_queue_stats(); > if (!q->stats) > - goto fail_split; > + goto fail_id; > > q->node = node_id; > > @@ -439,8 +434,6 @@ struct request_queue *blk_alloc_queue(int node_id, bool alloc_srcu) > > fail_stats: > blk_free_queue_stats(q->stats); > -fail_split: > - bioset_exit(&q->bio_split); > fail_id: > ida_free(&blk_queue_ida, q->id); > fail_srcu: > diff --git a/block/blk-merge.c b/block/blk-merge.c > index 3c3f785f558af..e657f1dc824cb 100644 > --- a/block/blk-merge.c > +++ b/block/blk-merge.c > @@ -328,26 +328,26 @@ static struct bio *blk_bio_segment_split(struct request_queue *q, > * Split a bio into two bios, chain the two bios, submit the second half and > * store a pointer to the first half in *@bio. If the second bio is still too > * big it will be split by a recursive call to this function. Since this > - * function may allocate a new bio from q->bio_split, it is the responsibility > - * of the caller to ensure that q->bio_split is only released after processing > - * of the split bio has finished. > + * function may allocate a new bio from disk->bio_split, it is the > + * responsibility of the caller to ensure that disk->bio_split is only released > + * after processing of the split bio has finished. > */ > void __blk_queue_split(struct request_queue *q, struct bio **bio, > unsigned int *nr_segs) > { > + struct bio_set *bs = &(*bio)->bi_bdev->bd_disk->bio_split; > struct bio *split = NULL; > > switch (bio_op(*bio)) { > case REQ_OP_DISCARD: > case REQ_OP_SECURE_ERASE: > - split = blk_bio_discard_split(q, *bio, &q->bio_split, nr_segs); > + split = blk_bio_discard_split(q, *bio, bs, nr_segs); > break; > case REQ_OP_WRITE_ZEROES: > - split = blk_bio_write_zeroes_split(q, *bio, &q->bio_split, > - nr_segs); > + split = blk_bio_write_zeroes_split(q, *bio, bs, nr_segs); > break; > default: > - split = blk_bio_segment_split(q, *bio, &q->bio_split, nr_segs); > + split = blk_bio_segment_split(q, *bio, bs, nr_segs); > break; > } Suggestion for a follow-up patch: we could save the *bio pointer in a local variable instead of constantly de-referencing bio. > > @@ -368,9 +368,9 @@ void __blk_queue_split(struct request_queue *q, struct bio **bio, > * > * Split a bio into two bios, chains the two bios, submit the second half and > * store a pointer to the first half in *@bio. Since this function may allocate > - * a new bio from q->bio_split, it is the responsibility of the caller to ensure > - * that q->bio_split is only released after processing of the split bio has > - * finished. > + * a new bio from disk->bio_split, it is the responsibility of the caller to > + * ensure that disk->bio_split is only released after processing of the split > + * bio has finished. > */ > void blk_queue_split(struct bio **bio) > { > diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c > index c0303026752d5..e1f009aba6fd2 100644 > --- a/block/blk-sysfs.c > +++ b/block/blk-sysfs.c > @@ -779,8 +779,6 @@ static void blk_release_queue(struct kobject *kobj) > if (queue_is_mq(q)) > blk_mq_release(q); > > - bioset_exit(&q->bio_split); > - > if (blk_queue_has_srcu(q)) > cleanup_srcu_struct(q->srcu); > > diff --git a/block/genhd.c b/block/genhd.c > index 44dfcf67ed96a..150494e8742b0 100644 > --- a/block/genhd.c > +++ b/block/genhd.c > @@ -1138,6 +1138,8 @@ static void disk_release(struct device *dev) > might_sleep(); > WARN_ON_ONCE(disk_live(disk)); > > + bioset_exit(&disk->bio_split); > + > blkcg_exit_queue(disk->queue); > > disk_release_events(disk); > @@ -1330,9 +1332,12 @@ struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id, > if (!disk) > goto out_put_queue; > > + if (bioset_init(&disk->bio_split, BIO_POOL_SIZE, 0, 0)) > + goto out_free_disk; > + > disk->bdi = bdi_alloc(node_id); > if (!disk->bdi) > - goto out_free_disk; > + goto out_free_bioset; > > /* bdev_alloc() might need the queue, set before the first call */ > disk->queue = q; > @@ -1370,6 +1375,8 @@ struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id, > iput(disk->part0->bd_inode); > out_free_bdi: > bdi_put(disk->bdi); > +out_free_bioset: > + bioset_exit(&disk->bio_split); > out_free_disk: > kfree(disk); > out_put_queue: > diff --git a/drivers/md/dm.c b/drivers/md/dm.c > index 54c2a23f4e55c..b163de50f3c6b 100644 > --- a/drivers/md/dm.c > +++ b/drivers/md/dm.c > @@ -1693,7 +1693,7 @@ static void dm_split_and_process_bio(struct mapped_device *md, > */ > WARN_ON_ONCE(!dm_io_flagged(io, DM_IO_WAS_SPLIT)); > io->split_bio = bio_split(bio, io->sectors, GFP_NOIO, > - &md->queue->bio_split); > + &md->disk->bio_split); > bio_chain(io->split_bio, bio); > trace_block_split(io->split_bio, bio->bi_iter.bi_sector); > submit_bio_noacct(bio); > diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h > index d04bdf549efa9..97d3ef8f3f416 100644 > --- a/include/linux/blkdev.h > +++ b/include/linux/blkdev.h > @@ -140,6 +140,8 @@ struct gendisk { > struct request_queue *queue; > void *private_data; > > + struct bio_set bio_split; > + > int flags; > unsigned long state; > #define GD_NEED_PART_SCAN 0 > @@ -531,7 +533,6 @@ struct request_queue { > > struct blk_mq_tag_set *tag_set; > struct list_head tag_set_list; > - struct bio_set bio_split; > > struct dentry *debugfs_dir; > struct dentry *sched_debugfs_dir; Looks good. Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
On Fri, Jul 22, 2022 at 02:56:13PM +0900, Damien Le Moal wrote: > Suggestion for a follow-up patch: we could save the *bio pointer in a > local variable instead of constantly de-referencing bio. I suspect a better calling convention might be to just return the new bio. I'll give that a spin for the follow up and see what it does to code size.
diff --git a/block/blk-core.c b/block/blk-core.c index 123468b9d2e43..59f13d011949d 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -377,7 +377,6 @@ static void blk_timeout_work(struct work_struct *work) struct request_queue *blk_alloc_queue(int node_id, bool alloc_srcu) { struct request_queue *q; - int ret; q = kmem_cache_alloc_node(blk_get_queue_kmem_cache(alloc_srcu), GFP_KERNEL | __GFP_ZERO, node_id); @@ -396,13 +395,9 @@ struct request_queue *blk_alloc_queue(int node_id, bool alloc_srcu) if (q->id < 0) goto fail_srcu; - ret = bioset_init(&q->bio_split, BIO_POOL_SIZE, 0, 0); - if (ret) - goto fail_id; - q->stats = blk_alloc_queue_stats(); if (!q->stats) - goto fail_split; + goto fail_id; q->node = node_id; @@ -439,8 +434,6 @@ struct request_queue *blk_alloc_queue(int node_id, bool alloc_srcu) fail_stats: blk_free_queue_stats(q->stats); -fail_split: - bioset_exit(&q->bio_split); fail_id: ida_free(&blk_queue_ida, q->id); fail_srcu: diff --git a/block/blk-merge.c b/block/blk-merge.c index 3c3f785f558af..e657f1dc824cb 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -328,26 +328,26 @@ static struct bio *blk_bio_segment_split(struct request_queue *q, * Split a bio into two bios, chain the two bios, submit the second half and * store a pointer to the first half in *@bio. If the second bio is still too * big it will be split by a recursive call to this function. Since this - * function may allocate a new bio from q->bio_split, it is the responsibility - * of the caller to ensure that q->bio_split is only released after processing - * of the split bio has finished. + * function may allocate a new bio from disk->bio_split, it is the + * responsibility of the caller to ensure that disk->bio_split is only released + * after processing of the split bio has finished. */ void __blk_queue_split(struct request_queue *q, struct bio **bio, unsigned int *nr_segs) { + struct bio_set *bs = &(*bio)->bi_bdev->bd_disk->bio_split; struct bio *split = NULL; switch (bio_op(*bio)) { case REQ_OP_DISCARD: case REQ_OP_SECURE_ERASE: - split = blk_bio_discard_split(q, *bio, &q->bio_split, nr_segs); + split = blk_bio_discard_split(q, *bio, bs, nr_segs); break; case REQ_OP_WRITE_ZEROES: - split = blk_bio_write_zeroes_split(q, *bio, &q->bio_split, - nr_segs); + split = blk_bio_write_zeroes_split(q, *bio, bs, nr_segs); break; default: - split = blk_bio_segment_split(q, *bio, &q->bio_split, nr_segs); + split = blk_bio_segment_split(q, *bio, bs, nr_segs); break; } @@ -368,9 +368,9 @@ void __blk_queue_split(struct request_queue *q, struct bio **bio, * * Split a bio into two bios, chains the two bios, submit the second half and * store a pointer to the first half in *@bio. Since this function may allocate - * a new bio from q->bio_split, it is the responsibility of the caller to ensure - * that q->bio_split is only released after processing of the split bio has - * finished. + * a new bio from disk->bio_split, it is the responsibility of the caller to + * ensure that disk->bio_split is only released after processing of the split + * bio has finished. */ void blk_queue_split(struct bio **bio) { diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index c0303026752d5..e1f009aba6fd2 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -779,8 +779,6 @@ static void blk_release_queue(struct kobject *kobj) if (queue_is_mq(q)) blk_mq_release(q); - bioset_exit(&q->bio_split); - if (blk_queue_has_srcu(q)) cleanup_srcu_struct(q->srcu); diff --git a/block/genhd.c b/block/genhd.c index 44dfcf67ed96a..150494e8742b0 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -1138,6 +1138,8 @@ static void disk_release(struct device *dev) might_sleep(); WARN_ON_ONCE(disk_live(disk)); + bioset_exit(&disk->bio_split); + blkcg_exit_queue(disk->queue); disk_release_events(disk); @@ -1330,9 +1332,12 @@ struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id, if (!disk) goto out_put_queue; + if (bioset_init(&disk->bio_split, BIO_POOL_SIZE, 0, 0)) + goto out_free_disk; + disk->bdi = bdi_alloc(node_id); if (!disk->bdi) - goto out_free_disk; + goto out_free_bioset; /* bdev_alloc() might need the queue, set before the first call */ disk->queue = q; @@ -1370,6 +1375,8 @@ struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id, iput(disk->part0->bd_inode); out_free_bdi: bdi_put(disk->bdi); +out_free_bioset: + bioset_exit(&disk->bio_split); out_free_disk: kfree(disk); out_put_queue: diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 54c2a23f4e55c..b163de50f3c6b 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1693,7 +1693,7 @@ static void dm_split_and_process_bio(struct mapped_device *md, */ WARN_ON_ONCE(!dm_io_flagged(io, DM_IO_WAS_SPLIT)); io->split_bio = bio_split(bio, io->sectors, GFP_NOIO, - &md->queue->bio_split); + &md->disk->bio_split); bio_chain(io->split_bio, bio); trace_block_split(io->split_bio, bio->bi_iter.bi_sector); submit_bio_noacct(bio); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index d04bdf549efa9..97d3ef8f3f416 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -140,6 +140,8 @@ struct gendisk { struct request_queue *queue; void *private_data; + struct bio_set bio_split; + int flags; unsigned long state; #define GD_NEED_PART_SCAN 0 @@ -531,7 +533,6 @@ struct request_queue { struct blk_mq_tag_set *tag_set; struct list_head tag_set_list; - struct bio_set bio_split; struct dentry *debugfs_dir; struct dentry *sched_debugfs_dir;
Only non-passthrough requests are split by the block layer and use the ->bio_split bio_set. Move it from the request_queue to the gendisk. Signed-off-by: Christoph Hellwig <hch@lst.de> --- block/blk-core.c | 9 +-------- block/blk-merge.c | 20 ++++++++++---------- block/blk-sysfs.c | 2 -- block/genhd.c | 9 ++++++++- drivers/md/dm.c | 2 +- include/linux/blkdev.h | 3 ++- 6 files changed, 22 insertions(+), 23 deletions(-)