Re: [PATCH] blk-mq: kick requeue list in blk_mq_requeue_request()

[Ming Lei]

On Tue, Jun 10, 2014 at 7:28 PM, Christoph Hellwig <hch@xxxxxx> wrote:
> On Tue, Jun 10, 2014 at 12:52:05PM +0800, Ming Lei wrote:
>> blk_mq_requeue_request() should kick off the requeue list so
>> that the request can be scheduled to queue finally.
>>
>> In nvme conversion patch, blk_mq_requeue_request() is called
>> to requeue failed request from completion handler, this patch
>> fixes the issue and makes the block API working as expected.
>
> I've intentionally kepts the two separate so that we can batch operations
> and just do a single kick for multiple requeued commands.
>

OK, but the API name is a bit confusing, and that is easy to cause
misuse, like in nvme.

Also requeue one request in completion handler may be a
common case, so maybe it is better to let blk_mq_requeue_request()
handle both adding to request list and kicking off, and introduce
blk_mq_prep_requeue_req()(or better name) to batch operations.


Thanks,
-- 
Ming Lei
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