Verma, Vishal L wrote:
> On Wed, 2022-07-13 at 11:50 -0700, Davidlohr Bueso wrote:
> > On Wed, 13 Jul 2022, Vishal Verma wrote:
> >
> > > Add a unit test to test writing, reading, and zeroing LSA aread for
> > > cxl_test based memdevs using ndctl commands.
> > >
> > > Cc: Dan Williams <[email protected]>
> > > Signed-off-by: Vishal Verma <[email protected]>
> > > ---
> > > test/cxl-labels.sh | 53 ++++++++++++++++++++++++++++++++++++++++++++++
> > > test/meson.build | 2 ++
> > > 2 files changed, 55 insertions(+)
> > > create mode 100644 test/cxl-labels.sh
> > >
> > > diff --git a/test/cxl-labels.sh b/test/cxl-labels.sh
> > > new file mode 100644
> > > index 0000000..ce73963
> > > --- /dev/null
> > > +++ b/test/cxl-labels.sh
> > > @@ -0,0 +1,53 @@
> > > +#!/bin/bash
> > > +# SPDX-License-Identifier: GPL-2.0
> > > +# Copyright (C) 2022 Intel Corporation. All rights reserved.
> > > +
> > > +. $(dirname $0)/common
> > > +
> > > +rc=1
> > > +
> > > +set -ex
> > > +
> > > +trap 'err $LINENO' ERR
> > > +
> > > +check_prereq "jq"
> > > +
> > > +modprobe -r cxl_test
> > > +modprobe cxl_test
> > > +udevadm settle
> > > +
> > > +test_label_ops()
> > > +{
> > > + nmem="$1"
> > > + lsa=$(mktemp /tmp/lsa-$nmem.XXXX)
> > > + lsa_read=$(mktemp /tmp/lsa-read-$nmem.XXXX)
> > > +
> > > + # determine LSA size
> > > + "$NDCTL" read-labels -o "$lsa_read" "$nmem"
> > > + lsa_size=$(stat -c %s "$lsa_read")
> > > +
> > > + dd "if=/dev/urandom" "of=$lsa" "bs=$lsa_size" "count=1"
> > > + "$NDCTL" write-labels -i "$lsa" "$nmem"
> > > + "$NDCTL" read-labels -o "$lsa_read" "$nmem"
> > > +
> > > + # compare what was written vs read
> > > + diff "$lsa" "$lsa_read"
> > > +
> > > + # zero the LSA and test
> > > + "$NDCTL" zero-labels "$nmem"
> > > + dd "if=/dev/zero" "of=$lsa" "bs=$lsa_size" "count=1"
> > > + "$NDCTL" read-labels -o "$lsa_read" "$nmem"
> > > + diff "$lsa" "$lsa_read"
> > > +
> > > + # cleanup
> > > + rm "$lsa" "$lsa_read"
> > > +}
> > > +
> > > +# find nmem devices corresponding to cxl memdevs
> > > +readarray -t nmems < <("$NDCTL" list -b cxl_test -Di | jq -r '.[].dev')
> >
> > s/$NDCTL/$CXL
> >
> > Beyond sharing a repo, I would really avoid mixing and matching ndctl and
> > cxl
> > tooling and thereby keep them self sufficient. I understand that there are
> > cases
> > where pmem specific operations can can be done reusing relevant
> > pmem/nvdimm/ndctl
> > machinery and interfaces, but I don't see this as the case for something
> > like lsa
> > unit testing.
> >
> > Thanks,
> > Davidlohr
> >
> Hi David,
>
> Thanks for the review - however this was intentional. cxl-cli may block
> LSA write access because libnvdimm could 'own' the label space.
>
> cxl memdev: action_write: mem0: has active nvdimm bridge, abort label write
>
> So the test has to use ndctl for label writes. Reads could be done with
> 'cxl', but for now there isn't a good/predictable mapping between ndctl
> 'nmemX' and cxl 'memX'. Once that is solved, either by a shared id
> allocator, or by listings showing the nmem->mem mapping, I will at
> least add another cxl read-labels here which would validate the same
> LSA data through cxl-cli.
I do think this test should eventually do both to validate that the
nvdimm passthrough and the native CXL operations are working. However,
the native CXL case needs a bit more infrastructure to disconnect the
memdev from nvdimm. Something like:
cxl disable-pmem mem0
cxl write-labels mem0 ...
You can add a "cxl read-labels" test though since that is not blocked
while the memdev is attached to nvdimm, only label writes.
