On 1/9/18 11:44 AM, Jens Axboe wrote:
> On 1/9/18 11:43 AM, Bart Van Assche wrote:
>> On Tue, 2018-01-09 at 11:27 -0700, Jens Axboe wrote:
>>> static inline int blk_mark_rq_complete(struct request *rq)
>>> {
>>> - return test_and_set_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags);
>>> + return test_and_set_bit(0, &rq->__deadline);
>>> }
>>>
>>> static inline void blk_clear_rq_complete(struct request *rq)
>>> {
>>> - clear_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags);
>>> + clear_bit(0, &rq->__deadline);
>>> +}
>>> +
>>> +static inline bool blk_rq_is_complete(struct request *rq)
>>> +{
>>> + return test_bit(0, &rq->__deadline);
>>> }
>>
>> Hello Jens,
>>
>> With this change setting or changing the deadline clears the COMPLETE flag.
>> Is that the intended behavior? If so, should perhaps a comment be added above
>> blk_rq_set_deadline()?
>
> Yeah, it's intentional. I can add a comment to that effect. It's only done
> before queueing - except for the case where we force a timeout, but for that
> it's only on the blk-mq side, which doesn't care.
Since we clear it when we init the request, we could also just leave the
bit intact when setting the deadline. That's probably the safer choice:
static inline void blk_rq_set_deadline(struct request *rq, unsigned long time)
{
rq->__deadline = (time & ~0x1UL) | (rq->__deadline & 0x1UL);
}
I'll test that, previous testing didn't find anything wrong with clearing
the bit, but this does seem safer.
--
Jens Axboe
