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To:     Axel Rasmussen <axelrasmussen@google.com>
CC:     Alexander Viro <viro@zeniv.linux.org.uk>,
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Subject: Re: [PATCH v3 5/6] userfaultfd: selftests: make /dev/userfaultfd
 testing configurable
Thread-Topic: [PATCH v3 5/6] userfaultfd: selftests: make /dev/userfaultfd
 testing configurable
Thread-Index: AQHYdfv6fDyMczipnEG9l81JJqWcj61RIZWA
Date:   Wed, 15 Jun 2022 22:25:11 +0000
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On Jun 1, 2022, at 2:09 PM, Axel Rasmussen <axelrasmussen@google.com> wrote=
:

> Instead of always testing both userfaultfd(2) and /dev/userfaultfd,
> let the user choose which to test.
>=20
> As with other test features, change the behavior based on a new
> command line flag. Introduce the idea of "test mods", which are
> generic (not specific to a test type) modifications to the behavior of
> the test. This is sort of borrowed from this RFC patch series [1], but
> simplified a bit.
>=20
> The benefit is, in "typical" configurations this test is somewhat slow
> (say, 30sec or something). Testing both clearly doubles it, so it may
> not always be desirable, as users are likely to use one or the other,
> but never both, in the "real world".
>=20
> [1]: https://patchwork.kernel.org/project/linux-mm/patch/20201129004548.1=
619714-14-namit@vmware.com/

Thanks for pushing this change! Your code is better.