On 9/27/19 9:50 AM, Roman Penyaev wrote:
On Fri, Sep 27, 2019 at 6:37 PM Bart Van Assche <bvanassche@xxxxxxx> wrote:
I agree that BLK_MQ_F_HOST_TAGS partitions a tag set across hardware
queues while ibnbd shares a single tag set across multiple hardware
queues. Since such sharing may be useful for other block drivers, isn't
that something that should be implemented in the block layer core
instead of in the ibnbd driver? If that logic would be moved into the
block layer core, would that allow to reuse the queue restarting logic
that already exists in the block layer core?
Definitely yes, but what other block drivers you have in mind?
I'd like to hear the opinion of Jens and Christoph about this topic. My
concern is that if the code for sharing a tag set across hwqs stays in
the ibnbd driver and if another block driver is submitted in the future
that needs the same logic that in order to end up with a single
implementation of the tag set sharing code that the authors of the new
driver would have to be asked to modify the ibnbd driver. I think it
would be inappropriate to ask the authors of such a new driver to modify
the ibnbd driver.
Bart.
