Integrate kmemleaks and igt

[Peter Senna Tschudin]

Dear Gustavo,

I am reaching out to you after Lucas suggested me to contact you about
integrating kmemleaks with igt.

Currently igt_runner has the -k option allowing the user to choose
between running one kmemleak scan after all tests, or to run one scan
after each test.

The problem with these approaches is that running once after all tests
is not very useful, and running one scan after each test imposes a large
performance overhead, making it not practical for our CI.

Lucas suggested an interesting alternative: Run a scan before module
bind and another after module unbind. This way we will add a relatively
small overhead while strategically running scans when we are more likely
to catch something interesting.

The problem now becomes how integrate kmemleak scans around bind and
unbind operations. Lucas suggested new hooks IGT_HOOK_PRE_MODULE_BIND
/IGT_HOOK_POST_MODULE_UNBIND as a potential approach.

Two related questions for you Gustavo. Any thoughts or preferences about
collecting kmemleak scans around bind operations? What about these new
proposed hooks, do they seem like the way to go?

Thank you,

Peter