Re: [PATCH v9 15/15] selftests/sgx: Add scripts for EPC cgroup testing

["Jarkko Sakkinen" <jarkko@kernel.org>]

On Thu Mar 28, 2024 at 5:54 AM EET, Haitao Huang wrote:
> On Wed, 27 Mar 2024 07:55:34 -0500, Jarkko Sakkinen <jarkko@kernel.org>  
> wrote:
>
> > On Mon, 2024-02-05 at 13:06 -0800, Haitao Huang wrote:
> >> The scripts rely on cgroup-tools package from libcgroup [1].
> >>
> >> To run selftests for epc cgroup:
> >>
> >> sudo ./run_epc_cg_selftests.sh
> >>
> >> To watch misc cgroup 'current' changes during testing, run this in a
> >> separate terminal:
> >>
> >> ./watch_misc_for_tests.sh current
> >>
> >> With different cgroups, the script starts one or multiple concurrent
> >> SGX
> >> selftests, each to run one unclobbered_vdso_oversubscribed test.Each
> >> of such test tries to load an enclave of EPC size equal to the EPC
> >> capacity available on the platform. The script checks results against
> >> the expectation set for each cgroup and reports success or failure.
> >>
> >> The script creates 3 different cgroups at the beginning with
> >> following
> >> expectations:
> >>
> >> 1) SMALL - intentionally small enough to fail the test loading an
> >> enclave of size equal to the capacity.
> >> 2) LARGE - large enough to run up to 4 concurrent tests but fail some
> >> if
> >> more than 4 concurrent tests are run. The script starts 4 expecting
> >> at
> >> least one test to pass, and then starts 5 expecting at least one test
> >> to fail.
> >> 3) LARGER - limit is the same as the capacity, large enough to run
> >> lots of
> >> concurrent tests. The script starts 8 of them and expects all pass.
> >> Then it reruns the same test with one process randomly killed and
> >> usage checked to be zero after all process exit.
> >>
> >> The script also includes a test with low mem_cg limit and LARGE
> >> sgx_epc
> >> limit to verify that the RAM used for per-cgroup reclamation is
> >> charged
> >> to a proper mem_cg.
> >>
> >> [1] https://github.com/libcgroup/libcgroup/blob/main/README
> >>
> >> Signed-off-by: Haitao Huang <haitao.huang@linux.intel.com>
> >> ---
> >> V7:
> >> - Added memcontrol test.
> >>
> >> V5:
> >> - Added script with automatic results checking, remove the
> >> interactive
> >> script.
> >> - The script can run independent from the series below.
> >> ---
> >>  .../selftests/sgx/run_epc_cg_selftests.sh     | 246
> >> ++++++++++++++++++
> >>  .../selftests/sgx/watch_misc_for_tests.sh     |  13 +
> >>  2 files changed, 259 insertions(+)
> >>  create mode 100755
> >> tools/testing/selftests/sgx/run_epc_cg_selftests.sh
> >>  create mode 100755
> >> tools/testing/selftests/sgx/watch_misc_for_tests.sh
> >>
> >> diff --git a/tools/testing/selftests/sgx/run_epc_cg_selftests.sh
> >> b/tools/testing/selftests/sgx/run_epc_cg_selftests.sh
> >> new file mode 100755
> >> index 000000000000..e027bf39f005
> >> --- /dev/null
> >> +++ b/tools/testing/selftests/sgx/run_epc_cg_selftests.sh
> >> @@ -0,0 +1,246 @@
> >> +#!/bin/bash
> >
> > This is not portable and neither does hold in the wild.
> >
> > It does not even often hold as it is not uncommon to place bash
> > to the path /usr/bin/bash. If I recall correctly, e.g. NixOS has
> > a path that is neither of those two.
> >
> > Should be #!/usr/bin/env bash
> >
> > That is POSIX compatible form.
> >
>
> Sure
>
> > Just got around trying to test this in NUC7 so looking into this in
> > more detail.
>
> Thanks. Could you please check if this version works for you?
>
> https://github.com/haitaohuang/linux/commit/3c424b841cf3cf66b085a424f4b537fbc3bbff6f
>
> >
> > That said can you make the script work with just "#!/usr/bin/env sh"
> > and make sure that it is busybox ash compatible?
>
> Yes.
>
> >
> > I don't see any necessity to make this bash only and it adds to the
> > compilation time of the image. Otherwise lot of this could be tested
> > just with qemu+bzImage+busybox(inside initramfs).
> >
>
> will still need cgroup-tools as you pointed out later. Compiling from its  
> upstream code OK?

Can you explain why you need it?

What is the thing you cannot do without it?

BR, Jarkko