Extend the existing hung_task detector test module to support multiple
lock types, including mutex and semaphore, with room for future additions
(e.g., spinlock, etc.). This module creates dummy files under
<debugfs>/hung_task, such as 'mutex' and 'semaphore'. The read process on
any of these files will sleep for enough long time (256 seconds) while
holding the respective lock. As a result, the second process will wait on
the lock for a prolonged duration and be detected by the hung_task
detector.
This change unifies the previous mutex-only sample into a single,
extensible hung_task_tests module, reducing code duplication and improving
maintainability.
Usage is:
> cd /sys/kernel/debug/hung_task
> cat mutex & cat mutex # Test mutex blocking
> cat semaphore & cat semaphore # Test semaphore blocking
Update the Kconfig description to reflect multiple debugfs files support.
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Lance Yang <[email protected]>
Signed-off-by: Zi Li <[email protected]>
Suggested-by: Masami Hiramatsu (Google) <[email protected]>
Acked-by: Masami Hiramatsu (Google) <[email protected]>
Cc: Anna Schumaker <[email protected]>
Cc: Boqun Feng <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Joel Granados <[email protected]>
Cc: John Stultz <[email protected]>
Cc: Kent Overstreet <[email protected]>
Cc: Mingzhe Yang <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Sergey Senozhatsky <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Tomasz Figa <[email protected]>
Cc: Waiman Long <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Yongliang Gao <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Zi Li