Re: [RFC PATCH 1/3] blk-mq: Add blk_mq_complete_request_direct()

[Jens Axboe <axboe@kernel.dk>]

On 10/15/21 10:15 AM, Sebastian Andrzej Siewior wrote:
> On 2021-10-15 09:03:28 [-0700], Christoph Hellwig wrote:
>> On Fri, Oct 15, 2021 at 05:14:10PM +0200, Sebastian Andrzej Siewior wrote:
>>> +void blk_mq_complete_request_direct(struct request *rq)
>>> +{
>>> +	WRITE_ONCE(rq->state, MQ_RQ_COMPLETE);
>>> +	rq->q->mq_ops->complete(rq);
>>> +}
>>
>> As this is called by the driver we known what ->complete this helper
>> would call.  So instead of doing this we could just call
>> blk_mq_set_request_complete and the actual completion helper.
>> The comment above it will need some updates of course.
> 
> So
> 	blk_mq_set_request_complete();
> 	mmc_blk_mq_complete();
> 
> for the mmc driver and no fiddling in the blk-mq then.

Just pass in the handler:

void blk_mq_complete_request_direct(struct request *rq,
				    void (*complete)(struct request *rq))
{
	WRITE_ONCE(rq->state, MQ_RQ_COMPLETE);
	complete(rq);
}

And we should probably put it in blk-mq.h so it inlines nicely, and
that'll be faster than the indirect call.

-- 
Jens Axboe