Re: [PATCH v2 1/1] nfsstat01: Update client RPC calls for kernel 6.9

[Petr Vorel <pvorel@suse.cz>]

> > On Aug 23, 2024, at 2:46 AM, Petr Vorel <pvorel@suse.cz> wrote:

> > Hi Chuck, Neil, all,

> >> On Wed, Aug 14, 2024 at 10:57:21AM +0200, Petr Vorel wrote:
> >>> 6.9 moved client RPC calls to namespace in "Make nfs stats visible in
> >>> network NS" patchet.

> >>> https://lore.kernel.org/linux-nfs/cover.1708026931.git.josef@toxicpanda.com/

> >>> Signed-off-by: Petr Vorel <pvorel@suse.cz>
> >>> ---
> >>> Changes v1->v2:
> >>> * Point out whole patchset, not just single commit
> >>> * Add a comment about the patchset

> >>> Hi all,

> >>> could you please ack this so that we have fixed mainline?

> >>> FYI Some parts has been backported, e.g.:
> >>> d47151b79e322 ("nfs: expose /proc/net/sunrpc/nfs in net namespaces")
> >>> to all stable/LTS: 5.4.276, 5.10.217, 5.15.159, 6.1.91, 6.6.31.

> >>> But most of that is not yet (but planned to be backported), e.g.
> >>> 93483ac5fec62 ("nfsd: expose /proc/net/sunrpc/nfsd in net namespaces")
> >>> see Chuck's patchset for 6.6
> >>> https://lore.kernel.org/linux-nfs/20240812223604.32592-1-cel@kernel.org/

> >>> Once all kernels up to 5.4 fixed we should update the version.

> >>> Kind regards,
> >>> Petr

> >>> testcases/network/nfs/nfsstat01/nfsstat01.sh | 9 ++++++++-
> >>> 1 file changed, 8 insertions(+), 1 deletion(-)

> >>> diff --git a/testcases/network/nfs/nfsstat01/nfsstat01.sh b/testcases/network/nfs/nfsstat01/nfsstat01.sh
> >>> index c2856eff1f..1beecbec43 100755
> >>> --- a/testcases/network/nfs/nfsstat01/nfsstat01.sh
> >>> +++ b/testcases/network/nfs/nfsstat01/nfsstat01.sh
> >>> @@ -15,7 +15,14 @@ get_calls()
> >>> local calls opt

> >>> [ "$name" = "rpc" ] && opt="r" || opt="n"
> >>> - ! tst_net_use_netns && [ "$nfs_f" != "nfs" ] && type="rhost"
> >>> +
> >>> + if tst_net_use_netns; then
> >>> + # "Make nfs stats visible in network NS" patchet
> >>> + # https://lore.kernel.org/linux-nfs/cover.1708026931.git.josef@toxicpanda.com/
> >>> + tst_kvcmp -ge "6.9" && [ "$nfs_f" = "nfs" ] && type="rhost"

> >> Hello Petr-

> >> My concern with this fix is it targets v6.9 specifically, yet we
> >> know these fixes will appear in LTS/stable kernels as well.

> > Great! I see you already fixed up to 5.15. I suppose the code is really
> > backportable to the other still active branches (5.10, 5.4, 4.19).

> I plan to work on backporting to v5.10 next week.

> I've been asked to look at v5.4, but I'm not sure how difficult
> that will be because it's missing a lot of NFSD patches. I will
> look into that in a couple of weeks.

> I'm very likely to punt on v4.19, though Oracle's stable backport
> team might try to tackle it at some point. (pun intended)

Thanks a lot for info, we'll see what you / your Oracle backport team will
manage in the end.

> > We discussed in v1 how to fix tests.  Neil suggested to fix the test the way so
> > that it works on all kernels. As I note [1]

> > 1) either we give up on checking the new functionality still works (if we
> > fallback to old behavior)
> > 2) or we need to specify from which kernel we expect new functionality
> > (so far it's 5.15, I suppose it will be older).

> > I would prefer 2) to have new functionality always tested.
> > Or am I missing something obvious?

> I don't quite understand the question.

> The "old functionality" of reporting these statistics globally
> is broken, but we're stuck with it in the older kernels. I guess
> you might want to confirm that, for a given recent kernel
> release, the stats are actually per-namespace -- that's what we
> expect in fixed kernels. Is that what you mean?

Yes. I'm just trying to say that Neil's proposal "work everywhere without
checking kernel version" will not work. I would like next week, after you send
5.10 patches to expect anything >= 5.10 will have new functionality
and update kernel version if more gets backported.

Kind regards,
Petr

> > Kind regards,
> > Petr

> > [1] https://lore.kernel.org/linux-nfs/172367387549.6062.7078032983644586462@noble.neil.brown.name/

> >> Neil Brown suggested an alternative approach that might not depend
> >> on knowing the specific kernel version:

> >> https://lore.kernel.org/linux-nfs/172078283934.15471.13377048166707693692@noble.neil.brown.name/

> >> HTH


> >>> + else
> >>> + [ "$nfs_f" != "nfs" ] && type="rhost"
> >>> + fi

> >>> if [ "$type" = "lhost" ]; then
> >>> calls="$(grep $name /proc/net/rpc/$nfs_f | cut -d' ' -f$field)"
> >>> -- 
> >>> 2.45.2