diff mbox series

[3/3] block: only call bio_integrity_prep() if necessary

Message ID 20240111160226.1936351-4-axboe@kernel.dk (mailing list archive)
State New, archived
Headers show
Series Integrity cleanups and optimization | expand

Commit Message

Jens Axboe Jan. 11, 2024, 4 p.m. UTC
Now that the queue is flag as having an actual profile or not, avoid
calling into the integrity code unless we have one. This removes some
overhead from blk_mq_submit_bio() if BLK_DEV_INTEGRITY is enabled and
we don't have any profiles attached, which is the default and expected
case.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 block/blk-mq.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Keith Busch Jan. 11, 2024, 4:28 p.m. UTC | #1
On Thu, Jan 11, 2024 at 09:00:21AM -0700, Jens Axboe wrote:
> Now that the queue is flag as having an actual profile or not, avoid
> calling into the integrity code unless we have one. This removes some
> overhead from blk_mq_submit_bio() if BLK_DEV_INTEGRITY is enabled and
> we don't have any profiles attached, which is the default and expected
> case.
> 
> Signed-off-by: Jens Axboe <axboe@kernel.dk>
> ---
>  block/blk-mq.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/block/blk-mq.c b/block/blk-mq.c
> index 37268656aae9..965e42a1bbde 100644
> --- a/block/blk-mq.c
> +++ b/block/blk-mq.c
> @@ -2961,7 +2961,8 @@ bool blk_mq_submit_bio(struct bio *bio)
>  
>  	bio_set_ioprio(bio);
>  
> -	if (!bio_integrity_prep(bio))
> +	if (test_bit(QUEUE_FLAG_INTG_PROFILE, &q->queue_flags) &&
> +	    !bio_integrity_prep(bio))
>  		return false;

I'm confused. The bio_integrity_prep() allocates the metadata buffer.
Drivers that were previoulsy using the 'nop' profile for odd formats
don't get a metadata buffer anymore?
Jens Axboe Jan. 11, 2024, 6:50 p.m. UTC | #2
On 1/11/24 9:28 AM, Keith Busch wrote:
> On Thu, Jan 11, 2024 at 09:00:21AM -0700, Jens Axboe wrote:
>> Now that the queue is flag as having an actual profile or not, avoid
>> calling into the integrity code unless we have one. This removes some
>> overhead from blk_mq_submit_bio() if BLK_DEV_INTEGRITY is enabled and
>> we don't have any profiles attached, which is the default and expected
>> case.
>>
>> Signed-off-by: Jens Axboe <axboe@kernel.dk>
>> ---
>>  block/blk-mq.c | 3 ++-
>>  1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/block/blk-mq.c b/block/blk-mq.c
>> index 37268656aae9..965e42a1bbde 100644
>> --- a/block/blk-mq.c
>> +++ b/block/blk-mq.c
>> @@ -2961,7 +2961,8 @@ bool blk_mq_submit_bio(struct bio *bio)
>>  
>>  	bio_set_ioprio(bio);
>>  
>> -	if (!bio_integrity_prep(bio))
>> +	if (test_bit(QUEUE_FLAG_INTG_PROFILE, &q->queue_flags) &&
>> +	    !bio_integrity_prep(bio))
>>  		return false;
> 
> I'm confused. The bio_integrity_prep() allocates the metadata buffer.
> Drivers that were previoulsy using the 'nop' profile for odd formats
> don't get a metadata buffer anymore?

Yeah, I just came to the same conclusion diving a bit deeper into
this. It's a bit of a mess imho, but you are right that previously,
by default, we'd get metadata buffers attached with a dummy profile
and with this we would not.

I'll drop this for now, I think this requires more involved work
to make this sane.
diff mbox series

Patch

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 37268656aae9..965e42a1bbde 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -2961,7 +2961,8 @@  bool blk_mq_submit_bio(struct bio *bio)
 
 	bio_set_ioprio(bio);
 
-	if (!bio_integrity_prep(bio))
+	if (test_bit(QUEUE_FLAG_INTG_PROFILE, &q->queue_flags) &&
+	    !bio_integrity_prep(bio))
 		return false;
 
 	if (plug) {