Re: [PATCH] DAX: enable iostat for read/write

[Dan Williams]

On Mon, Oct 17, 2016 at 10:40 AM, Kani, Toshimitsu <toshi.kani@xxxxxxx> wrote:
> On Sat, 2016-10-15 at 18:54 +1100, Dave Chinner wrote:
>> On Fri, Oct 14, 2016 at 11:25:13AM -0600, Toshi Kani wrote:
>  :
>> > +static void dax_iostat_start(struct gendisk *disk, struct iov_iter
>> > *iter,
>> > +     unsigned long *start)
>> > +{
>> > +int rw = iov_iter_rw(iter);
>> > +int sec = iov_iter_count(iter) >> 9;
>> > +int cpu = part_stat_lock();
>> > +
>> > +*start = jiffies;
>> > +part_round_stats(cpu, &disk->part0);
>> > +part_stat_inc(cpu, &disk->part0, ios[rw]);
>> > +part_stat_add(cpu, &disk->part0, sectors[rw], sec);
>> > +part_inc_in_flight(&disk->part0, rw);
>> > +part_stat_unlock();
>> > +}
>>
>> Why reimplement generic_start_io_acct() and generic_end_io_acct()?
>
> It was modeled after __nd_iostat_start() / nd_iostart_end().  I agree
> that we can use generic_start_io_acct() and generic_end_io_acct() here.
>
> Should we also change the nd interface to use the generic version as
> well?

Yes, sounds good to me.