Re: [PATCH RFC 10/14] block, bfq: add Early Queue Merge (EQM)

From: Paolo Valente
Date: Wed Mar 15 2017 - 13:03:43 EST



> Il giorno 15 mar 2017, alle ore 17:56, Jens Axboe <axboe@xxxxxxxxx> ha scritto:
>
> On 03/04/2017 09:01 AM, Paolo Valente wrote:
>> @@ -6330,7 +7012,41 @@ static void bfq_rq_enqueued(struct bfq_data *bfqd, struct bfq_queue *bfqq,
>>
>> static void __bfq_insert_request(struct bfq_data *bfqd, struct request *rq)
>> {
>> - struct bfq_queue *bfqq = RQ_BFQQ(rq);
>> + struct bfq_queue *bfqq = RQ_BFQQ(rq), *new_bfqq;
>> +
>> + /*
>> + * An unplug may trigger a requeue of a request from the device
>> + * driver: make sure we are in process context while trying to
>> + * merge two bfq_queues.
>> + */
>> + if (!in_interrupt()) {
>
> What's the reason for this?

None :(

Just pre-existing, working code that I did not update, sorry.

> Don't use in_interrupt() to guide any of
> your decision making here.
>

Of course, sorry for these silly mistakes.

Thanks,
Paolo

> --
> Jens Axboe
>