Re: [PATCH v4 1/2] locking/rwsem: Add DEBUG_RWSEMS to look for lock/unlock mismatches

[Waiman Long]

On 03/28/2018 09:32 PM, Davidlohr Bueso wrote:
> On Wed, 28 Mar 2018, Waiman Long wrote:
>
>> +config DEBUG_RWSEMS
>> +    bool "RW Semaphore debugging: basic checks"
>> +    depends on DEBUG_KERNEL && RWSEM_SPIN_ON_OWNER
>
> Why depend on RWSEM_SPIN_ON_OWNER? Doesn't everyone benefit from this?
> For example, DEBUG_MUTEXES does not need it.
>
> Thanks,
> Davidlohr

Because it checks the owner field which is present only if
RWSEM_SPIN_ON_OWNER is defined. Mutex is different in the sense that the
owner field is always there no matter if MUTEX_SPIN_ON_OWNER is set or not.

Cheers,
Longman