| Message ID | 20240226103004.281412-5-hch@lst.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [01/16] block: add a queue_limits_set helper | expand |
Hi, 在 2024/02/26 18:29, Christoph Hellwig 写道: > Add a few helpers that wrap the block queue limits API for use in MD. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > drivers/md/md.c | 37 +++++++++++++++++++++++++++++++++++++ > drivers/md/md.h | 3 +++ > 2 files changed, 40 insertions(+) > > diff --git a/drivers/md/md.c b/drivers/md/md.c > index 75266c34b1f99b..23823823f80c6b 100644 > --- a/drivers/md/md.c > +++ b/drivers/md/md.c > @@ -5699,6 +5699,43 @@ static const struct kobj_type md_ktype = { > > int mdp_major = 0; > > +/* stack the limit for all rdevs into lim */ > +void mddev_stack_rdev_limits(struct mddev *mddev, struct queue_limits *lim) > +{ > + struct md_rdev *rdev; > + > + rdev_for_each(rdev, mddev) { > + queue_limits_stack_bdev(lim, rdev->bdev, rdev->data_offset, > + mddev->gendisk->disk_name); > + } > +} > +EXPORT_SYMBOL_GPL(mddev_stack_rdev_limits); > + > +/* apply the extra stacking limits from a new rdev into mddev */ > +int mddev_stack_new_rdev(struct mddev *mddev, struct md_rdev *rdev) > +{ > + struct queue_limits lim = queue_limits_start_update(mddev->queue); > + > + queue_limits_stack_bdev(&lim, rdev->bdev, rdev->data_offset, > + mddev->gendisk->disk_name); > + return queue_limits_commit_update(mddev->queue, &lim); > +} > +EXPORT_SYMBOL_GPL(mddev_stack_new_rdev); > + > +/* update the optimal I/O size after a reshape */ > +void mddev_update_io_opt(struct mddev *mddev, unsigned int nr_stripes) > +{ > + struct queue_limits lim; > + int ret; > + > + blk_mq_freeze_queue(mddev->queue); > + lim = queue_limits_start_update(mddev->queue); > + lim.io_opt = lim.io_min * nr_stripes; > + ret = queue_limits_commit_update(mddev->queue, &lim); > + blk_mq_unfreeze_queue(mddev->queue); Any reason to use blk_mq_freeze/unfreeze_queue ? I don't think this is meaningful for raid, this only wait for IO submission, not IO done. raid should already handle concurrent IO with reshape, so I think this can just be removed. Thanks, Kuai > +} > +EXPORT_SYMBOL_GPL(mddev_update_io_opt); > + > static void mddev_delayed_delete(struct work_struct *ws) > { > struct mddev *mddev = container_of(ws, struct mddev, del_work); > diff --git a/drivers/md/md.h b/drivers/md/md.h > index 8d881cc597992f..25b19614aa3239 100644 > --- a/drivers/md/md.h > +++ b/drivers/md/md.h > @@ -860,6 +860,9 @@ void md_autostart_arrays(int part); > int md_set_array_info(struct mddev *mddev, struct mdu_array_info_s *info); > int md_add_new_disk(struct mddev *mddev, struct mdu_disk_info_s *info); > int do_md_run(struct mddev *mddev); > +void mddev_stack_rdev_limits(struct mddev *mddev, struct queue_limits *lim); > +int mddev_stack_new_rdev(struct mddev *mddev, struct md_rdev *rdev); > +void mddev_update_io_opt(struct mddev *mddev, unsigned int nr_stripes); > > extern const struct block_device_operations md_fops; > >
On Mon, Feb 26, 2024 at 07:38:17PM +0800, Yu Kuai wrote: > Any reason to use blk_mq_freeze/unfreeze_queue ? I don't think this is > meaningful for raid, this only wait for IO submission, not IO done. > > raid should already handle concurrent IO with reshape, so I think this > can just be removed. We can't just change limits under the driver if I/Os are being sumitted. That is one of the points of the whole queue limits exercises.
Hi, 在 2024/02/27 22:36, Christoph Hellwig 写道: > On Mon, Feb 26, 2024 at 07:38:17PM +0800, Yu Kuai wrote: >> Any reason to use blk_mq_freeze/unfreeze_queue ? I don't think this is >> meaningful for raid, this only wait for IO submission, not IO done. >> >> raid should already handle concurrent IO with reshape, so I think this >> can just be removed. > > We can't just change limits under the driver if I/Os are being sumitted. > That is one of the points of the whole queue limits exercises. > Agree with this, it's just these apis can't gurantee this in raid, there could still be IO inflight, perhaps you can use: mddev_suspend(mddev) ... mddev_resume(mddev) Thanks, Kuai > . >
diff --git a/drivers/md/md.c b/drivers/md/md.c index 75266c34b1f99b..23823823f80c6b 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -5699,6 +5699,43 @@ static const struct kobj_type md_ktype = { int mdp_major = 0; +/* stack the limit for all rdevs into lim */ +void mddev_stack_rdev_limits(struct mddev *mddev, struct queue_limits *lim) +{ + struct md_rdev *rdev; + + rdev_for_each(rdev, mddev) { + queue_limits_stack_bdev(lim, rdev->bdev, rdev->data_offset, + mddev->gendisk->disk_name); + } +} +EXPORT_SYMBOL_GPL(mddev_stack_rdev_limits); + +/* apply the extra stacking limits from a new rdev into mddev */ +int mddev_stack_new_rdev(struct mddev *mddev, struct md_rdev *rdev) +{ + struct queue_limits lim = queue_limits_start_update(mddev->queue); + + queue_limits_stack_bdev(&lim, rdev->bdev, rdev->data_offset, + mddev->gendisk->disk_name); + return queue_limits_commit_update(mddev->queue, &lim); +} +EXPORT_SYMBOL_GPL(mddev_stack_new_rdev); + +/* update the optimal I/O size after a reshape */ +void mddev_update_io_opt(struct mddev *mddev, unsigned int nr_stripes) +{ + struct queue_limits lim; + int ret; + + blk_mq_freeze_queue(mddev->queue); + lim = queue_limits_start_update(mddev->queue); + lim.io_opt = lim.io_min * nr_stripes; + ret = queue_limits_commit_update(mddev->queue, &lim); + blk_mq_unfreeze_queue(mddev->queue); +} +EXPORT_SYMBOL_GPL(mddev_update_io_opt); + static void mddev_delayed_delete(struct work_struct *ws) { struct mddev *mddev = container_of(ws, struct mddev, del_work); diff --git a/drivers/md/md.h b/drivers/md/md.h index 8d881cc597992f..25b19614aa3239 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -860,6 +860,9 @@ void md_autostart_arrays(int part); int md_set_array_info(struct mddev *mddev, struct mdu_array_info_s *info); int md_add_new_disk(struct mddev *mddev, struct mdu_disk_info_s *info); int do_md_run(struct mddev *mddev); +void mddev_stack_rdev_limits(struct mddev *mddev, struct queue_limits *lim); +int mddev_stack_new_rdev(struct mddev *mddev, struct md_rdev *rdev); +void mddev_update_io_opt(struct mddev *mddev, unsigned int nr_stripes); extern const struct block_device_operations md_fops;
Add a few helpers that wrap the block queue limits API for use in MD. Signed-off-by: Christoph Hellwig <hch@lst.de> --- drivers/md/md.c | 37 +++++++++++++++++++++++++++++++++++++ drivers/md/md.h | 3 +++ 2 files changed, 40 insertions(+)