The patches introduce a set of tests used to verify the following functionality:
- Controlling the amount of memory used by page cache with memory.cache
- Enforcing migration of cgroup's pages to one or multiple target NUMA nodes
with memory.numa_migrate.
Changes in v4:
- Replace EXPECT with ASSERT.
- Drop crc32 as it is slow (~1 GiB/s on the test machine) and prevents the test
region pages from becoming "active" enough.
- Improve error checking by explicitly asserting a positive return code instead
of asserting absence of a negative error code (where possible).
- Use periodic stat checks with timeouts instead of sleep() calls.
- Remove the expected-to-fail markers from the "inactive" tests. The
inactive_anon test is executed with MGLRU (lru_gen) disabled. See the commit
message for more details.
- Unify verification functionality for active and inactive pages in
numa_migrate.
- Provide some test description at the beginning of the source files.
Notes for reviewers:
- The kselftest harness is designed in such a way that it does not allow to
skip any tests that have been registered before the execution started. This
means, there is no safe and sane way to interrupt the overall flow if one of
the tests has failed. I tried using a state variable but each of the
individual tests seems to be executed in a subprocess so if it fails it has
no way to change anything outside. I also tried creating a marker file but it
is also troublesome as the main harness function terminates the calling
process on its own without letting the external caller perform any cleanup
(e.g. to remove the marker file after all tests have finished).
- Regarding the ASSERT macro and invocation of the teardown function:
- Teardown is not automatically called if ASSERT is used in FIXTURE_SETUP.
- Teardown is called if ASSERT is used from the test functions defined with
the TEST macro and its variants.
- Teardown will be called if ASSERT is used from any non-harness-macro
defined function if the "context" variables (_metadata etc.) are visible
within the function's scope and the function is called from the process
running the main test function.
- Teardown can theoretically be called if ASSERT is used from a child process
started by the main test function if "context" is passed to the function(s)
executed by the child process but in reality it makes little sense as it is
possible that teardown would be then executed twice leading to potentially
harmful outcome (once by the ASSERT plumbing from the child process and
once by the main test function because the child has failed).
Dmitry Sepp (2):
selftests: cgroup: test page cache limiting feature
selftests: cgroup: test numa migration of lruvecs
tools/testing/selftests/cgroup/Makefile | 4 +
tools/testing/selftests/cgroup/config | 4 +
tools/testing/selftests/cgroup/test_cache.c | 327 ++++++++
.../selftests/cgroup/test_numa_migrate.c | 765 ++++++++++++++++++
4 files changed, 1100 insertions(+)
create mode 100644 tools/testing/selftests/cgroup/test_cache.c
create mode 100644 tools/testing/selftests/cgroup/test_numa_migrate.c
--
2.47.1
_______________________________________________
Devel mailing list
[email protected]
https://lists.openvz.org/mailman/listinfo/devel
