Re: [PATCH] locking/osq: Drop the overload of osq lock

From: panxinhui
Date: Sat Jun 25 2016 - 13:29:14 EST



> 在 2016年6月26日,00:13,Peter Zijlstra <peterz@xxxxxxxxxxxxx> 写道:
>
> On Sat, Jun 25, 2016 at 06:09:22PM +0200, Peter Zijlstra wrote:
>> That works here, but it would not work for the need_resched() in
>> mutex_spin_on_owner() and mutex_optimistic_spin() which need equal
>> treatment.
>>
>> Because those too we want to limit.
>>
>> The count thing, while a little more cumbersome, is more widely
>> applicable than just the one OSQ case where we happen to have a cpu
>> number.
>
> Although I suppose that mutex_spin_on_owner() (and with that the rsem
> variant) could use task_cpu(lock->owner) once we've established that the
> owner pointer is still valid.
>
>
yes, What I am going to fix next is these XXX_spin_on_owner, including mutex_spin_on_owner, rwsem_spin_on_owner ….

by the way I still think mutex_unlock has a big overload too.