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    Subject[PATCH 0/4] deterministic random testing
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    This is a bit of a mixed bag.

    The background is that I have some sort() and list_sort() rework
    planned, but as part of that series I want to extend their their test
    suites somewhat to make sure I don't goof up - and I want to use lots
    of random list lengths with random contents to increase the chance of
    somebody eventually hitting "hey, sort() is broken when the length is
    3 less than a power of 2 and only the last two elements are out of
    order". But when such a case is hit, it's vitally important that the
    developer can reproduce the exact same test case, which means using a
    deterministic sequence of random numbers.

    Since Petr noticed [1] the non-determinism in test_printf in
    connection with Arpitha's work on rewriting it to kunit, this prompted
    me to use test_printf as a first place to apply that principle, and
    get the infrastructure in place that will avoid repeating the "module
    parameter/seed the rnd_state/report the seed used" boilerplate in each
    module.

    Shuah, assuming the kselftest_module.h changes are ok, I think it's
    most natural if you carry these patches, though I'd be happy with any
    other route as well.

    [1] https://lore.kernel.org/lkml/20200821113710.GA26290@alley/


    Rasmus Villemoes (4):
    prandom.h: add *_state variant of prandom_u32_max
    kselftest_module.h: unconditionally expand the KSTM_MODULE_GLOBALS()
    macro
    kselftest_module.h: add struct rnd_state and seed parameter
    lib/test_printf.c: use deterministic sequence of random numbers

    Documentation/dev-tools/kselftest.rst | 2 --
    include/linux/prandom.h | 29 ++++++++++++++++
    lib/test_bitmap.c | 3 --
    lib/test_printf.c | 13 ++++---
    lib/test_strscpy.c | 2 --
    tools/testing/selftests/kselftest_module.h | 40 ++++++++++++++++++----
    6 files changed, 72 insertions(+), 17 deletions(-)

    --
    2.23.0

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