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Subject: Re: [PATCH v2 1/1] blk-mq: fill header with kernel-doc
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        Gabriel Krisman Bertazi <krisman@collabora.com>
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From:   Bart Van Assche <bvanassche@acm.org>
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Date:   Fri, 11 Oct 2019 10:00:41 -0700
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On 10/10/19 1:38 PM, André Almeida wrote:
> Seems that it's not clear for me the role of these members. Could you
> please check if those definitions make sense for you?
> 
> - hctx->dispatch: This queue is used for requests that are ready to be
> dispatched to the hardware but for some reason (e.g. lack of resources,
> the hardware is to busy and can't get more requests) could not be sent
> to the hardware. As soon as the driver can send new requests, those
> queued at this list will be sent first for a more fair dispatch. Since
> those requests are at the hctx, they can't be requeued or rescheduled
> anymore.
> 
> - request_queue->requeue_list: This list is used when it's not possible
> to send the request to the associated hctx. This can happen if the
> associated CPU or hctx is not available anymore. When requeueing those
> requests, it will be possible to send them to new and function queues.

Hi André,

The hctx->dispatch description looks mostly fine. Can the following part 
be left out since it looks confusing to me: "Since those requests are at 
the hctx, they can't be requeued or rescheduled anymore."

How about changing the requeue_list description into the following: 
"requests requeued by a call to blk_mq_requeue_request()".

Thanks,

Bart.