Re: [PATCH V2 1/7] block/rbd: bump librbd requirement to luminous release

[Peter Lieven]

Am 15.02.21 um 13:13 schrieb Kevin Wolf:
> Am 15.02.2021 um 12:45 hat Peter Lieven geschrieben:
> > Am 15.02.21 um 12:41 schrieb Daniel P. Berrangé:
> > > On Mon, Feb 15, 2021 at 12:32:24PM +0100, Peter Lieven wrote:
> > > > Am 15.02.21 um 11:24 schrieb Daniel P. Berrangé:
> > > > > On Tue, Jan 26, 2021 at 12:25:34PM +0100, Peter Lieven wrote:
> > > > > > even luminous (version 12.2) is unmaintained for over 3 years now.
> > > > > > Bump the requirement to get rid of the ifdef'ry in the code.
> > > > > We have clear rules on when we bump minimum versions, determined by
> > > > > the OS platforms we target:
> > > > >
> > > > >      https://qemu.readthedocs.io/en/latest/system/build-platforms.html
> > > > >
> > > > > At this time RHEL-7 is usually the oldest platform, and it
> > > > > builds with RBD 10.2.5, so we can't bump the version to 12.2.
> > > > >
> > > > > I'm afraid this patch has to be dropped.
> > > > I have asked exactly this question before I started work on this series and got 
> > > > reply
> > > >
> > > > from Jason that he sees no problem in bumping to a release which is already 
> > > > unmaintained
> > > >
> > > > for 3 years.
> > > I'm afraid Jason is wrong here.  It doesn't matter what the upstream
> > > consider the support status to be. QEMU targets what the OS vendors
> > > ship, and they still consider this to be a supported version.
> >
> > Okay, but the whole coroutine stuff would get a total mess with all
> > the ifdef'ry.
> Hm, but how are these ifdefs even related to the coroutine conversation?
> It's a bit more code that you're moving around, but shouldn't it be
> unchanged from the old code, just moving from an AIO callback to a
> coroutine? Or am I missing some complications?


No, the ifdef's only come back in for the write zeroes part.


> > Would it be an option to make a big ifdef in the rbd driver? One with
> > old code for < 12.0.0 and one
> >
> > with new code for >= 12.0.0?
> I don't think this is a good idea, this would be a huge mess to
> maintain.
>
> The conversion is probably a good idea in general, simply because it's
> more in line with the rest of the block layer, but I don't think it adds
> anything per se, so it's hard to justify such duplication with the
> benefits it brings.


I would wait for Jasons comment on the rbd part of the series and then spin a V3

with a for-6.1 tag.


Peter