| Message ID | 20220727162300.3089193-4-hch@lst.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/6] block: change the blk_queue_split calling convention | expand |
On 7/27/22 18:22, 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> > Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> > Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> > --- > block/blk-core.c | 9 +-------- > block/blk-merge.c | 7 ++++--- > block/blk-sysfs.c | 2 -- > block/genhd.c | 8 +++++++- > drivers/md/dm.c | 2 +- > include/linux/blkdev.h | 3 ++- > 6 files changed, 15 insertions(+), 16 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 6e29fb28584ef..30872a3537648 100644 > --- a/block/blk-merge.c > +++ b/block/blk-merge.c > @@ -331,18 +331,19 @@ static struct bio *bio_split_rw(struct bio *bio, struct request_queue *q, > struct bio *__bio_split_to_limits(struct bio *bio, struct request_queue *q, > unsigned int *nr_segs) > { > + struct bio_set *bs = &bio->bi_bdev->bd_disk->bio_split; > struct bio *split; > What happens for nvme-multipath? While I know that we shouldn't split on a path, experience shows that we _will_ do it eventually. Hence, shouldn't we take precaution for hidden disks with no gendisk attached here? Cheers, Hannes
On Thu, Jul 28, 2022 at 10:07:14AM +0200, Hannes Reinecke wrote: >> + struct bio_set *bs = &bio->bi_bdev->bd_disk->bio_split; >> struct bio *split; >> > > What happens for nvme-multipath? > While I know that we shouldn't split on a path, experience shows that we > _will_ do it eventually. > Hence, shouldn't we take precaution for hidden disks with no gendisk > attached here? Every block device including nvme-multioath has a valid gendisk.
On Thu, Jul 28, 2022 at 10:07:14AM +0200, Hannes Reinecke wrote: > On 7/27/22 18:22, 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> > > Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> > > Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> > > --- > > block/blk-core.c | 9 +-------- > > block/blk-merge.c | 7 ++++--- > > block/blk-sysfs.c | 2 -- > > block/genhd.c | 8 +++++++- > > drivers/md/dm.c | 2 +- > > include/linux/blkdev.h | 3 ++- > > 6 files changed, 15 insertions(+), 16 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 6e29fb28584ef..30872a3537648 100644 > > --- a/block/blk-merge.c > > +++ b/block/blk-merge.c > > @@ -331,18 +331,19 @@ static struct bio *bio_split_rw(struct bio *bio, struct request_queue *q, > > struct bio *__bio_split_to_limits(struct bio *bio, struct request_queue *q, > > unsigned int *nr_segs) > > { > > + struct bio_set *bs = &bio->bi_bdev->bd_disk->bio_split; > > struct bio *split; > > What happens for nvme-multipath? > While I know that we shouldn't split on a path, experience shows that we > _will_ do it eventually. You mean contiguous bios should be mapped to one same path? If yes, at least the current block layer can't do that, here dm-mapth is same with nvme-mpath, since bio is always split first, and the split small bio can be mapped to other path. Thanks, Ming
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 6e29fb28584ef..30872a3537648 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -331,18 +331,19 @@ static struct bio *bio_split_rw(struct bio *bio, struct request_queue *q, struct bio *__bio_split_to_limits(struct bio *bio, struct request_queue *q, unsigned int *nr_segs) { + struct bio_set *bs = &bio->bi_bdev->bd_disk->bio_split; struct bio *split; switch (bio_op(bio)) { case REQ_OP_DISCARD: case REQ_OP_SECURE_ERASE: - split = bio_split_discard(bio, q, nr_segs, &q->bio_split); + split = bio_split_discard(bio, q, nr_segs, bs); break; case REQ_OP_WRITE_ZEROES: - split = bio_split_write_zeroes(bio, q, nr_segs, &q->bio_split); + split = bio_split_write_zeroes(bio, q, nr_segs, bs); break; default: - split = bio_split_rw(bio, q, nr_segs, &q->bio_split); + split = bio_split_rw(bio, q, nr_segs, bs); break; } 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..e3daebeaf9ae9 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -1139,6 +1139,7 @@ static void disk_release(struct device *dev) WARN_ON_ONCE(disk_live(disk)); blkcg_exit_queue(disk->queue); + bioset_exit(&disk->bio_split); disk_release_events(disk); kfree(disk->random); @@ -1330,9 +1331,12 @@ 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 +1374,8 @@ 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 a014a002298bd..b7458f2dd3e45 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 5eef8d2eddc1c..49dcd31e283e8 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;