Re: [PATCH] ext4: flag as supporting buffered async reads

From: Jens Axboe
Date: Tue Aug 25 2020 - 10:18:37 EST


On 8/24/20 4:56 AM, Jens Axboe wrote:
> On 8/22/20 9:48 AM, Jens Axboe wrote:
>> On 8/22/20 8:33 AM, Theodore Y. Ts'o wrote:
>>> On Fri, Aug 21, 2020 at 03:26:35PM -0600, Jens Axboe wrote:
>>>>>>> Resending this one, as I've been carrying it privately since May. The
>>>>>>> necessary bits are now upstream (and XFS/btrfs equiv changes as well),
>>>>>>> please consider this one for 5.9. Thanks!
>>>>>>
>>>>>> The necessary commit only hit upstream as of 5.9-rc1, unless I'm
>>>>>> missing something? It's on my queue to send to Linus once I get my
>>>>>> (late) ext4 primary pull request for 5.9.
>>>>>
>>>>> Right, it went in at the start of the merge window for 5.9. Thanks Ted!
>>>>
>>>> Didn't see it in the queue that just sent in, is it still queued up?
>>>
>>> It wasn't in the queue which I queued up because that was based on
>>> 5.8-rc4. Linus was a bit grumpy (fairly so) because it was late, and
>>> that's totally on me.
>>>
>>> He has said that he's going to start ignoring pull requests that
>>> aren't fixes only if this becomes a pattern, so while I can send him
>>> another pull request which will just have that one change, there are
>>> no guarantees he's going to take it at this late date.
>>>
>>> Sorry, when you sent me the commit saying that the changes that were
>>> needed were already upstream on August 3rd, I thought that meant that
>>> they were aready in Linus's tree. I should have checked and noticed
>>> that that in fact "ext4: flag as supporting buffered async reads"
>>> wasn't compiling against Linus's upstream tree, so I didn't realize
>>> this needed to be handled as a special case during the merge window.
>>
>> Well to be honest, this kind of sucks. I've been posting it since May,
>> and the ideal approach would have been to just ack it and I could have
>> carried it in my tree. That's what we did for btrfs and XFS, both of
>> which have it.
>>
>> The required patches *were* upstreamed on August 3rd, which is why I
>> mentioned that. But yes, not in 5.8 or earlier, of course.
>>
>> So I suggest that you either include it for the next pull request for
>> Linus, or that I put it in with your ack. Either is fine with me. I'd
>> consider this a "dropping the ball" kind of thing, it's not like the
>> patch hasn't been in linux-next or hasn't been ready for months. This
>> isn't some "oh I wrote this feature after the merge window" event. It'd
>> be a real shame to ship 5.9 and ext4 not have support for the more
>> efficient async buffered reads, imho, especially since the two other
>> major local file systems already have it.
>>
>> Let me know what you think.
>
> Ted, can you make a call on this, please? It's now post -rc2. Let's
> get this settled and included, one way or another.

Daily ping on this one...

--
Jens Axboe