[LTP] [PATCH V3 4/5] libswap: add function to prealloc contiguous file

[Petr Vorel]

> On Tue, Jan 23, 2024 at 11:47 PM Petr Vorel <pvorel@suse.cz> wrote:

> > > Hi Petr,

> > > On Tue, Jan 23, 2024 at 8:37 PM Petr Vorel <pvorel@suse.cz> wrote:

> > > > Hi Li,

> > > > > Hi Li,

> > > > > swapoff01 fails on TMPDIR on btrfs (regardless kernel version):

> > > > FYI it works on Tumbleweed with 6.7 kernel. It's broken on some older
> > SLES
> > > > with 5.14 and all older kernels. I suppose with nocow (fixes I
> > suggested
> > > > previously) would work as expected (TPASS, or TCONF on kernel < 5.0).


> > > You're right.

> > > We have to guarantee the swapfile is a contiguous file whatever the FS
> > type
> > > is.
> > > So here making use of make_swapfile() is a hard requirement.
> > > And, I don't think the file first with 65536 blocks (in swapoff01) is not
> > > necessary.

> > Maybe not, but now we test on single swap size. Testing small swap and big
> > swap
> > was IMHO more testing coverage (various filesystems behave differently on
> > different size), but given this would be more important for whole
> > .all_filesystems = 1 testing I'm ok with the change.


> Ok, that could be achieved by customizing the swap file size later.
> It's not very hard. But now I don't want to increase the patchset number
> just for more coverage, that will be a burden for release testing work.

Hi Li,

+1, sure.

Kind regards,
Petr