Message ID | 20210324121927.362525-14-ming.lei@redhat.com (mailing list archive) |
---|---|
State | Superseded, archived |
Delegated to: | Mike Snitzer |
Headers | show |
Series | block: support bio based io polling | expand |
On Wed, Mar 24 2021 at 8:19am -0400, Ming Lei <ming.lei@redhat.com> wrote: > From: Jeffle Xu <jefflexu@linux.alibaba.com> > > IO polling is enabled when all underlying target devices are capable > of IO polling. The sanity check supports the stacked device model, in > which one dm device may be build upon another dm device. In this case, > the mapped device will check if the underlying dm target device > supports IO polling. > > Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com> > Signed-off-by: Ming Lei <ming.lei@redhat.com> > --- > drivers/md/dm-table.c | 24 ++++++++++++++++++++++++ > drivers/md/dm.c | 14 ++++++++++++++ > include/linux/device-mapper.h | 1 + > 3 files changed, 39 insertions(+) > ... > diff --git a/drivers/md/dm.c b/drivers/md/dm.c > index 50b693d776d6..fe6893b078dc 100644 > --- a/drivers/md/dm.c > +++ b/drivers/md/dm.c > @@ -1720,6 +1720,19 @@ static blk_qc_t dm_submit_bio(struct bio *bio) > return ret; > } > > +static bool dm_bio_poll_capable(struct gendisk *disk) > +{ > + int ret, srcu_idx; > + struct mapped_device *md = disk->private_data; > + struct dm_table *t; > + > + t = dm_get_live_table(md, &srcu_idx); > + ret = dm_table_supports_poll(t); > + dm_put_live_table(md, srcu_idx); > + > + return ret; > +} > + I know this code will only get called by blk-core if bio-based but there isn't anything about this method's implementation that is inherently bio-based only. So please rename from dm_bio_poll_capable to dm_poll_capable Other than that: Reviewed-by: Mike Snitzer <snitzer@redhat.com> > /*----------------------------------------------------------------- > * An IDR is used to keep track of allocated minor numbers. > *---------------------------------------------------------------*/ > @@ -3132,6 +3145,7 @@ static const struct pr_ops dm_pr_ops = { > }; > > static const struct block_device_operations dm_blk_dops = { > + .poll_capable = dm_bio_poll_capable, > .submit_bio = dm_submit_bio, > .open = dm_blk_open, > .release = dm_blk_close, -- dm-devel mailing list dm-devel@redhat.com https://listman.redhat.com/mailman/listinfo/dm-devel
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index 95391f78b8d5..a8f3575fb118 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -1509,6 +1509,12 @@ struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector) return &t->targets[(KEYS_PER_NODE * n) + k]; } +static int device_not_poll_capable(struct dm_target *ti, struct dm_dev *dev, + sector_t start, sector_t len, void *data) +{ + return !blk_queue_poll(bdev_get_queue(dev->bdev)); +} + /* * type->iterate_devices() should be called when the sanity check needs to * iterate and check all underlying data devices. iterate_devices() will @@ -1559,6 +1565,11 @@ static int count_device(struct dm_target *ti, struct dm_dev *dev, return 0; } +int dm_table_supports_poll(struct dm_table *t) +{ + return !dm_table_any_dev_attr(t, device_not_poll_capable, NULL); +} + /* * Check whether a table has no data devices attached using each * target's iterate_devices method. @@ -2079,6 +2090,19 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q, dm_update_keyslot_manager(q, t); blk_queue_update_readahead(q); + + /* + * Check for request-based device is remained to + * dm_mq_init_request_queue()->blk_mq_init_allocated_queue(). + * For bio-based device, only set QUEUE_FLAG_POLL when all underlying + * devices supporting polling. + */ + if (__table_type_bio_based(t->type)) { + if (dm_table_supports_poll(t)) + blk_queue_flag_set(QUEUE_FLAG_POLL, q); + else + blk_queue_flag_clear(QUEUE_FLAG_POLL, q); + } } unsigned int dm_table_get_num_targets(struct dm_table *t) diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 50b693d776d6..fe6893b078dc 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1720,6 +1720,19 @@ static blk_qc_t dm_submit_bio(struct bio *bio) return ret; } +static bool dm_bio_poll_capable(struct gendisk *disk) +{ + int ret, srcu_idx; + struct mapped_device *md = disk->private_data; + struct dm_table *t; + + t = dm_get_live_table(md, &srcu_idx); + ret = dm_table_supports_poll(t); + dm_put_live_table(md, srcu_idx); + + return ret; +} + /*----------------------------------------------------------------- * An IDR is used to keep track of allocated minor numbers. *---------------------------------------------------------------*/ @@ -3132,6 +3145,7 @@ static const struct pr_ops dm_pr_ops = { }; static const struct block_device_operations dm_blk_dops = { + .poll_capable = dm_bio_poll_capable, .submit_bio = dm_submit_bio, .open = dm_blk_open, .release = dm_blk_close, diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h index 7f4ac87c0b32..31bfd6f70013 100644 --- a/include/linux/device-mapper.h +++ b/include/linux/device-mapper.h @@ -538,6 +538,7 @@ unsigned int dm_table_get_num_targets(struct dm_table *t); fmode_t dm_table_get_mode(struct dm_table *t); struct mapped_device *dm_table_get_md(struct dm_table *t); const char *dm_table_device_name(struct dm_table *t); +int dm_table_supports_poll(struct dm_table *t); /* * Trigger an event.