| Message ID | 20241216201901.2670237-3-bvanassche@acm.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Move blk_mq_submit_bio() error handling | expand |
On Mon, Dec 16, 2024 at 12:19:01PM -0800, Bart Van Assche wrote: > diff --git a/block/blk-mq.c b/block/blk-mq.c > index 8d2aab4d9ba9..80eb91296142 100644 > --- a/block/blk-mq.c > +++ b/block/blk-mq.c > @@ -2971,8 +2971,6 @@ static struct request *blk_mq_get_new_requests(struct request_queue *q, > if (rq) > return rq; > rq_qos_cleanup(q, bio); > - if (bio->bi_opf & REQ_NOWAIT) > - bio_wouldblock_error(bio); > return NULL; Please turn this into: if (rq) rq_qos_cleanup(q, bio); return rq; Otherwise this looks like a nice cleanup.
On 12/16/24 8:18 PM, Christoph Hellwig wrote: > On Mon, Dec 16, 2024 at 12:19:01PM -0800, Bart Van Assche wrote: >> diff --git a/block/blk-mq.c b/block/blk-mq.c >> index 8d2aab4d9ba9..80eb91296142 100644 >> --- a/block/blk-mq.c >> +++ b/block/blk-mq.c >> @@ -2971,8 +2971,6 @@ static struct request *blk_mq_get_new_requests(struct request_queue *q, >> if (rq) >> return rq; >> rq_qos_cleanup(q, bio); >> - if (bio->bi_opf & REQ_NOWAIT) >> - bio_wouldblock_error(bio); >> return NULL; > > Please turn this into: > > if (rq) > rq_qos_cleanup(q, bio); > return rq; > > Otherwise this looks like a nice cleanup. It seems to me that there is a typo in the above code? Unless if you tell me otherwise, I will assume that this is what you meant: diff --git a/block/blk-mq.c b/block/blk-mq.c index 8d2aab4d9ba9..f4300e608ed8 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2968,12 +2968,9 @@ static struct request *blk_mq_get_new_requests(struct request_queue *q, } rq = __blk_mq_alloc_requests(&data); - if (rq) - return rq; - rq_qos_cleanup(q, bio); - if (bio->bi_opf & REQ_NOWAIT) - bio_wouldblock_error(bio); - return NULL; + if (!rq) + rq_qos_cleanup(q, bio); + return rq; } /* @@ -3106,8 +3103,11 @@ void blk_mq_submit_bio(struct bio *bio) blk_mq_use_cached_rq(rq, plug, bio); } else { rq = blk_mq_get_new_requests(q, plug, bio, nr_segs); - if (unlikely(!rq)) + if (unlikely(!rq)) { + if (bio->bi_opf & REQ_NOWAIT) + bio_wouldblock_error(bio); goto queue_exit; + } } trace_block_getrq(bio); Thanks, Bart.
On Tue, Dec 17, 2024 at 01:06:12PM -0800, Bart Van Assche wrote: > It seems to me that there is a typo in the above code? Unless if you tell > me otherwise, I will assume that this is what you meant: Yes.
diff --git a/block/blk-mq.c b/block/blk-mq.c index 8d2aab4d9ba9..80eb91296142 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2971,8 +2971,6 @@ static struct request *blk_mq_get_new_requests(struct request_queue *q, if (rq) return rq; rq_qos_cleanup(q, bio); - if (bio->bi_opf & REQ_NOWAIT) - bio_wouldblock_error(bio); return NULL; } @@ -3106,8 +3104,11 @@ void blk_mq_submit_bio(struct bio *bio) blk_mq_use_cached_rq(rq, plug, bio); } else { rq = blk_mq_get_new_requests(q, plug, bio, nr_segs); - if (unlikely(!rq)) + if (unlikely(!rq)) { + if (bio->bi_opf & REQ_NOWAIT) + bio_wouldblock_error(bio); goto queue_exit; + } } trace_block_getrq(bio);
The error handling code in blk_mq_get_new_requests() cannot be understood without knowing that this function is only called by blk_mq_submit_bio(). Hence move the code for handling blk_mq_get_new_requests() failures into blk_mq_submit_bio(). Cc: Damien Le Moal <dlemoal@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Bart Van Assche <bvanassche@acm.org> --- block/blk-mq.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)