| Message ID | 1499154912-10420-7-git-send-email-sagi@grimberg.me (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Jul 04, 2017 at 10:55:10AM +0300, Sagi Grimberg wrote: > Unlike blk_mq_stop_hw_queues, blk_mq_quiesce_queue respects the > submission path rcu grace. quiesce the queue before iterating > on live tags, or performing device io quiescing. > > Signed-off-by: Sagi Grimberg <sagi@grimberg.me> > --- > drivers/block/mtip32xx/mtip32xx.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c > index 61b046f256ca..69a62aeace2a 100644 > --- a/drivers/block/mtip32xx/mtip32xx.c > +++ b/drivers/block/mtip32xx/mtip32xx.c > @@ -950,7 +950,7 @@ static int mtip_quiesce_io(struct mtip_port *port, unsigned long timeout) > unsigned long to; > bool active = true; > > - blk_mq_stop_hw_queues(port->dd->queue); > + blk_mq_quiesce_queue(port->dd->queue); > > to = jiffies + msecs_to_jiffies(timeout); > do { > @@ -970,10 +970,10 @@ static int mtip_quiesce_io(struct mtip_port *port, unsigned long timeout) > break; > } while (time_before(jiffies, to)); > > - blk_mq_start_stopped_hw_queues(port->dd->queue, true); > + blk_mq_unquiesce_queue(port->dd->queue); > return active ? -EBUSY : 0; > err_fault: > - blk_mq_start_stopped_hw_queues(port->dd->queue, true); > + blk_mq_unquiesce_queue(port->dd->queue); > return -EFAULT; > } The above change looks correct. > > @@ -3995,7 +3995,7 @@ static int mtip_block_remove(struct driver_data *dd) > dd->disk->disk_name); > > blk_freeze_queue_start(dd->queue); > - blk_mq_stop_hw_queues(dd->queue); > + blk_mq_quiesce_queue(dd->queue); > blk_mq_tagset_busy_iter(&dd->tags, mtip_no_dev_cleanup, dd); We still need to unquiesce queue for avoiding hanging blk_freeze_queue() in blk_cleanup_queue() since any new request queued during quiescing can't be dispatched to driver/device. There are other blk_mq_tagset_busy_iter() in mtip_service_thread(), which looks need quiesce too. This case is even worse, because both mtip_abort_cmd() and mtip_queue_cmd() do not check if the req is started.
>> @@ -3995,7 +3995,7 @@ static int mtip_block_remove(struct driver_data *dd) >> dd->disk->disk_name); >> >> blk_freeze_queue_start(dd->queue); >> - blk_mq_stop_hw_queues(dd->queue); >> + blk_mq_quiesce_queue(dd->queue); >> blk_mq_tagset_busy_iter(&dd->tags, mtip_no_dev_cleanup, dd); > > We still need to unquiesce queue for avoiding hanging blk_freeze_queue() > in blk_cleanup_queue() since any new request queued during quiescing > can't be dispatched to driver/device. Yes, already added it in v2. > There are other blk_mq_tagset_busy_iter() in mtip_service_thread(), > which looks need quiesce too. Wasn't sure about those two... I agree it looks like quiescing is needed, will add in v2. > This case is even worse, because both > mtip_abort_cmd() and mtip_queue_cmd() do not check if the req is > started. Its easy enough to add.
diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c index 61b046f256ca..69a62aeace2a 100644 --- a/drivers/block/mtip32xx/mtip32xx.c +++ b/drivers/block/mtip32xx/mtip32xx.c @@ -950,7 +950,7 @@ static int mtip_quiesce_io(struct mtip_port *port, unsigned long timeout) unsigned long to; bool active = true; - blk_mq_stop_hw_queues(port->dd->queue); + blk_mq_quiesce_queue(port->dd->queue); to = jiffies + msecs_to_jiffies(timeout); do { @@ -970,10 +970,10 @@ static int mtip_quiesce_io(struct mtip_port *port, unsigned long timeout) break; } while (time_before(jiffies, to)); - blk_mq_start_stopped_hw_queues(port->dd->queue, true); + blk_mq_unquiesce_queue(port->dd->queue); return active ? -EBUSY : 0; err_fault: - blk_mq_start_stopped_hw_queues(port->dd->queue, true); + blk_mq_unquiesce_queue(port->dd->queue); return -EFAULT; } @@ -3995,7 +3995,7 @@ static int mtip_block_remove(struct driver_data *dd) dd->disk->disk_name); blk_freeze_queue_start(dd->queue); - blk_mq_stop_hw_queues(dd->queue); + blk_mq_quiesce_queue(dd->queue); blk_mq_tagset_busy_iter(&dd->tags, mtip_no_dev_cleanup, dd); /*
Unlike blk_mq_stop_hw_queues, blk_mq_quiesce_queue respects the submission path rcu grace. quiesce the queue before iterating on live tags, or performing device io quiescing. Signed-off-by: Sagi Grimberg <sagi@grimberg.me> --- drivers/block/mtip32xx/mtip32xx.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)