Re: [PATCH V6 2/6] block: tracking request allocation with q_usage_counter

Hannes Reinecke
2017-09-27T06:10:08Z

On 09/27/2017 07:48 AM, Ming Lei wrote:
> This usage is basically same with blk-mq, so that we can
> support to freeze legacy queue easily.
>
> Also 'wake_up_all(&q->mq_freeze_wq)' has to be moved
> into blk_set_queue_dying() since both legacy and blk-mq
> may wait on the wait queue of .mq_freeze_wq.
>
> Signed-off-by: Ming Lei <ming.lei@redhat.com>
> ---
> block/blk-core.c | 14 ++++++++++++++
> block/blk-mq.c | 7 -------
> 2 files changed, 14 insertions(+), 7 deletions(-)
>
As indicated in the other (similar) patch from Bart, we have a customer
report running into a q_usage_counter underflow with legacy-sq.
So this patch is actually a bugfix.

Reviewed-by: Hannes Reinecke <hare@suse.com>

Cheers,

Hannes
--
Dr. Hannes Reinecke Teamlead Storage & Networking
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