Re: Locking API testsuite: Failures

[Ingo Molnar <mingo@elte.hu>]

* Peter Teoh <htmldeveloper@gmail.com> wrote:

> Several questions:

[...]
> 3.  My current .config (which gave rise to the failure errors) [...]

You should have read this bit of the self-test printout:

[    0.004000] 133 out of 218 testcases failed, as expected. |

there was no unexpected failure. A real test-case failure is displayed 
as: 'FAILED', and you'll get a verbose printout about the unexpected 
testcase failures.

> 1.   I noticed there is a Kconfig.debug with this entry:
> 
> config DEBUG_LOCKING_API_SELFTESTS
>         bool "Locking API boot-time self-tests"
>         depends on DEBUG_KERNEL
>         help
>           Say Y here if you want the kernel to run a short self-test during
>           bootup. The self-test checks whether common types of locking bugs
>           are detected by debugging mechanisms or not. (if you disable
>           lock debugging then those bugs wont be detected of course.)
>           The following locking APIs are covered: spinlocks, rwlocks,
>           mutexes and rwsems.
> 
> How do I use this Kconfig.debug, just overwriting the standard
> lib/Kconfig? [...]

no, that messes up the kernel. Kconfig.debug is a separate, unique 
kconfig file with debugging related options.

> 2.   So does it make sense to  compile with
> CONFIG_DEBUG_LOCKING_API_SELFTESTS without CONFIG_LOCKDEP?

yes. It shows the kinds of bugs we dont find when PROVE_LOCKING is 
disabled. It also shows that the test-cases are working as expected.

	Ingo