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

From: Kani, Toshimitsu
Date: Mon Oct 17 2016 - 13:56:26 EST


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:
Â:
> > +static void dax_iostat_start(struct gendisk *disk, struct iov_iter
> > *iter,
> > + ÂÂÂÂÂunsigned 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(). ÂI agree
that we can useÂgeneric_start_io_acct() and generic_end_io_acct() here.

Should we also change the nd interface to use the generic version as
well?

Thanks,
-Toshi

ps.
Sorry I realized this comment after sending out v2...