On 8/8/23 14:19, Jens Axboe wrote:
On 8/4/23 9:47?AM, Bart Van Assche wrote:
Writes in sequential write required zones must happen at the write
pointer. Even if the submitter of the write commands (e.g. a filesystem)
submits writes for sequential write required zones in order, the block
layer or the storage controller may reorder these write commands.
The zone locking mechanism in the mq-deadline I/O scheduler serializes
write commands for sequential zones. Some but not all storage controllers
require this serialization. Introduce a new request queue flag to allow
block drivers to indicate that they preserve the order of write commands
and thus do not require serialization of writes per zone.
Looking at how this is used, why not call it QUEUE_FLAG_ZONE_WRITE_LOCK
instead? That'd make the code easier to immediately grok, rather than
deal with double negations.
Hi Jens,
Do I understand correctly that you want me to set the
QUEUE_FLAG_ZONE_WRITE_LOCK flag for all request queues by adding it to
QUEUE_FLAG_MQ_DEFAULT and also that the UFS driver should clear the
QUEUE_FLAG_ZONE_WRITE_LOCK flag?
Thanks,
Bart.
