Re: [PATCH v3] rwsem: Support optimistic spinning

[Jason Low]

On Thu, May 1, 2014 at 9:39 AM, Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx> wrote:
> On Wed, 2014-04-30 at 20:21 -0700, Davidlohr Bueso wrote:
>
>> +
>> +static inline bool rwsem_can_spin_on_owner(struct rw_semaphore *sem)
>> +{
>> +     struct task_struct *owner;
>> +     bool on_cpu = true;
>> +
>> +     if (need_resched())
>> +             return 0;
>> +
>> +     rcu_read_lock();
>> +     owner = ACCESS_ONCE(sem->owner);
>> +     if (owner)
>> +             on_cpu = owner->on_cpu;
>> +     rcu_read_unlock();
>> +
>> +     /*
>> +      * If lock->owner is not set, the mutex owner may have
>> +      * just acquired it and not set the owner yet or the mutex
>
> Nitpick. Change the above 2 mutex in comment to rwsem.

On that note, we may also change "lock->owner" to "sem->owner" for consistency.

Thanks,
Jason
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