| Message ID | 20170924070247.25560-11-damien.lemoal@wdc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
> + > + struct request_queue *q; Do you really need the queue backpointer? At least as far as this patch is concerned we could just pass the queue on to deadline_enable_zones_wlock and be fine. And in general we should always passing the q, as we can trivial go from queue to deadline_data using queue->elevator->elevator_data. > +static int deadline_zoned_init_queue(struct request_queue *q, > + struct deadline_data *dd) > +{ > + if (!blk_queue_is_zoned(q) || > + !blk_queue_nr_zones(q)) { Shouldn't !blk_queue_nr_zones(q) be enough? If not both conditionals could easily fit into the same line, and I'd be tempted to move them to the caller and call deadline_enable_zones_wlock straight from there. > @@ -341,6 +387,15 @@ static int dd_init_queue(struct request_queue *q, struct elevator_type *e) > spin_lock_init(&dd->lock); > INIT_LIST_HEAD(&dd->dispatch); > > + dd->q = q; > + spin_lock_init(&dd->zone_lock); > + ret = deadline_zoned_init_queue(q, dd); > + if (ret) { > + kfree(dd); > + kobject_put(&eq->kobj); > + return ret; > + } > + > q->elevator = eq; > return 0; This should probably grow goto based unwinding, e.g. int ret = -ENOMEM; ... dd = kzalloc_node(sizeof(*dd), GFP_KERNEL, q->node); if (!dd) goto out_put_object; ... if (blk_queue_nr_zones(q))) { ret = deadline_enable_zones_wlock(...); if (ret) goto out_free_dd; } q->elevator = eq; return 0; out_free_dd: kfree(dd); out_put_object kobject_put(&eq->kobj); return ret;
On 9/24/17 17:14, Christoph Hellwig wrote: >> + >> + struct request_queue *q; > > Do you really need the queue backpointer? At least as far as this > patch is concerned we could just pass the queue on to > deadline_enable_zones_wlock and be fine. And in general we should > always passing the q, as we can trivial go from queue to deadline_data > using queue->elevator->elevator_data. This is for the sysfs zones_wlock store function which does not give the queue. Instead of this backpointer, I can copy the queue node, number of zones and zone model so that cdeadline_enable_zones_wlock() can be called equally from init_queue context and from the sysfs zones_wlock store context. >> +static int deadline_zoned_init_queue(struct request_queue *q, >> + struct deadline_data *dd) >> +{ >> + if (!blk_queue_is_zoned(q) || >> + !blk_queue_nr_zones(q)) { > > Shouldn't !blk_queue_nr_zones(q) be enough? If not both conditionals > could easily fit into the same line, and I'd be tempted to move them > to the caller and call deadline_enable_zones_wlock straight from there. OK. Will update. >> @@ -341,6 +387,15 @@ static int dd_init_queue(struct request_queue *q, struct elevator_type *e) >> spin_lock_init(&dd->lock); >> INIT_LIST_HEAD(&dd->dispatch); >> >> + dd->q = q; >> + spin_lock_init(&dd->zone_lock); >> + ret = deadline_zoned_init_queue(q, dd); >> + if (ret) { >> + kfree(dd); >> + kobject_put(&eq->kobj); >> + return ret; >> + } >> + >> q->elevator = eq; >> return 0; > > This should probably grow goto based unwinding, e.g. OK. Will update. Thanks !
diff --git a/block/mq-deadline.c b/block/mq-deadline.c index a1cad4331edd..53b1d16179ad 100644 --- a/block/mq-deadline.c +++ b/block/mq-deadline.c @@ -60,6 +60,10 @@ struct deadline_data { spinlock_t lock; struct list_head dispatch; + + struct request_queue *q; + spinlock_t zone_lock; + unsigned long *zones_wlock; }; static inline struct rb_root * @@ -300,6 +304,24 @@ static struct request *dd_dispatch_request(struct blk_mq_hw_ctx *hctx) return rq; } +static int deadline_enable_zones_wlock(struct deadline_data *dd, + gfp_t gfp_mask) +{ + dd->zones_wlock = kzalloc_node(BITS_TO_LONGS(blk_queue_nr_zones(dd->q)) + * sizeof(unsigned long), + gfp_mask, dd->q->node); + if (!dd->zones_wlock) + return -ENOMEM; + + return 0; +} + +static void deadline_disable_zones_wlock(struct deadline_data *dd) +{ + kfree(dd->zones_wlock); + dd->zones_wlock = NULL; +} + static void dd_exit_queue(struct elevator_queue *e) { struct deadline_data *dd = e->elevator_data; @@ -307,16 +329,40 @@ static void dd_exit_queue(struct elevator_queue *e) BUG_ON(!list_empty(&dd->fifo_list[READ])); BUG_ON(!list_empty(&dd->fifo_list[WRITE])); + deadline_disable_zones_wlock(dd); kfree(dd); } /* + * initialize zoned block device related elevator private data. + */ +static int deadline_zoned_init_queue(struct request_queue *q, + struct deadline_data *dd) +{ + if (!blk_queue_is_zoned(q) || + !blk_queue_nr_zones(q)) { + /* + * Regular drive, or non-conforming zoned block device. + * Do not use zone write locking. + */ + return 0; + } + + /* + * Enable zone write locking by default for any zoned + * block device model. + */ + return deadline_enable_zones_wlock(dd, GFP_KERNEL); +} + +/* * initialize elevator private data (deadline_data). */ static int dd_init_queue(struct request_queue *q, struct elevator_type *e) { struct deadline_data *dd; struct elevator_queue *eq; + int ret; eq = elevator_alloc(q, e); if (!eq) @@ -341,6 +387,15 @@ static int dd_init_queue(struct request_queue *q, struct elevator_type *e) spin_lock_init(&dd->lock); INIT_LIST_HEAD(&dd->dispatch); + dd->q = q; + spin_lock_init(&dd->zone_lock); + ret = deadline_zoned_init_queue(q, dd); + if (ret) { + kfree(dd); + kobject_put(&eq->kobj); + return ret; + } + q->elevator = eq; return 0; }
Introduce new fields to mq-deadline private data to support zoned block devices. The fields added provide a back pointer to the device request queue to give access to the device zone model and zone information. Also added are a zone bitmap used to implement zone write locking and a spinlock to atomically handle zone locking with other processing. Modify mq-dealine init_queue and exit_queue elevator methods to handle initialization and cleanup of these fields. Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> --- block/mq-deadline.c | 55 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+)