Re: [PATCHSET] Add support for simplified async direct-io

[Jens Axboe <axboe@kernel.dk>]

On 11/17/2016 05:50 AM, Christoph Hellwig wrote:
> On Wed, Nov 16, 2016 at 09:43:57PM -0700, Jens Axboe wrote:
>> OK, I'm getting reasonably happy with it now:
>>
>> http://git.kernel.dk/cgit/linux-block/log/?h=for-4.10/hch-dio
>>
>> Sharing the FUA setting to avoid the manual flush between the two, and
>> removing the remnants of SYNC support from __blkdev_direct_IO().
>>
>> I'll fire off some overnight testing now and leave it for the day.
>
> This looks reasonable, a couple questions and comments:
>
>  - why the 8 * BIO_MAX_PAGES in the call to iov_iter_npages,
>    that probably needs a comment

Looks like I forgot to push out the latest changes, that is gone. We're
just using + 1 now to see if we should use the multibio function or not.

>  - I'll probably need to write up a proper changelog and fold
>    in at least the multi_bio patch.

That's fine.

>  - I'd just return the op from dio_bio_set_write_op instead of
>    passing the bio, that reads a lot easier.

Fine with me.

>  - I should probably get rid of blkdev_dio_pool in favour
>    of bio_kmalloc

Agree, though not a requirement imho.

> I can look into doing these fixups this afternoon and prepare a tre
> for you.

Sounds good.

-- 
Jens Axboe