Re: [PATCH] generic: add missing $FSX_AVOID to fsx invocations

[Zorro Lang <zlang@redhat.com>]

On Fri, Jul 28, 2023 at 04:30:40PM -0400, Theodore Ts'o wrote:
> On Wed, Feb 08, 2023 at 02:26:56AM +0800, Zorro Lang wrote:
> > fstests has merged below change 2 month ago:
> >   [PATCH] fstests: update group name according to xfs_io command requirement
> >   https://lore.kernel.org/fstests/20221108183242.3362013-1-zlang@kernel.org/
> > 
> > So I'd like to check if it helps for the problem you described above?
> > If not, I think we can think about the patch you metioned above.
> 
> Oops, sorry, this got lost in my inbox.  :-(
> 
> It definitely helped, thanks.  My one observation about this patch is
> that it's a one-time fix-up.  I tried rerunning the script referenced
> in the patch, and there were 11 tests that it "fixed up".  Now, they
> were all adding tests to the "prealloc" group, which I think you had
> deliberately excluded, because they weren't actually testing prealloc,
> but it's the worry that future fstests developers might forget to set
> the group name correctly, which is why I still have "common: introduce
> XFS_IO_AVOID env var"[1] as an out of tree patch.
> 
> [1] https://lore.kernel.org/all/1445107518-32022-1-git-send-email-tytso@mit.edu/
> 
> It's a small change, it almost never conflicts with upstream changes
> (generally the only time I have to deal with a conflcit when rebasing
> is when a new environment variable is added to the documentation in
> README), and it means that when I run "kvm-xfstests --no-collapse", my
> wrapper scripts do this:
> 
>     no_collapse)
>         ALL_FSSTRESS_AVOID="$ALL_FSSTRESS_AVOID -f collapse=0"
>         ALL_FSX_AVOID="$ALL_FSX_AVOID -C"
>         ALL_XFS_IO_AVOID="$ALL_XFS_IO_AVOID fcollapse"
>         FSTESTSET="$FSTESTSET -x collapse"
>         ;;
> 
> and I'm *guaranteed* to make sure that any tests involving
> collapse_range will be skipped.  Do I strictly speaking need the
> out-of-tree patch in [1], probably not, assuming the group list is
> always kept up to date, and to be honest it's been a *long* time since
> I've never needed to use gce-xfstests --no-collapse or --no-insert.

Many thanks, glad to know that helps.

Tell the truth, the "XFS_IO_AVOID" is more like a trick of the "exclude
individual tests (./check -X)". If a case contains an operation (e.g. collapse),
we can't skip it by group name, but can do that through a trick. That
cause fstests leave a "group name missing bug" there, and we even try to hide
it.

So the best way I think is anyone who can't skip a test properly by a
group name, please report that bug to fstests. Let's fix it. BTW, I really
tried to notice the missed group name from that day when I review new cases,
especially if there're some obvious xfs_io operations. But some operations
might be hide, feel free to report/fix that if anyone find :)

Thanks,
Zorro

> 
> However, the cost of keeping the out-of-tree patch in my local
> xfstests git repo is quite low, so I've just kept it.  But do I *need*
> it?  Arguably, no, which is why I haven't been bugging you about it.
> :-)
> 
> 						- Ted
>