Messages in this thread |  | | From | "Kani, Toshimitsu" <> | Subject | Re: [PATCH] DAX: enable iostat for read/write | Date | Fri, 14 Oct 2016 18:47:36 +0000 |
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On Fri, 2016-10-14 at 10:35 -0700, Dan Williams wrote: > On Fri, Oct 14, 2016 at 10:25 AM, Toshi Kani <toshi.kani@hpe.com> > wrote: > > > > DAX IO path does not support iostat, but its metadata IO path does. > > Therefore, iostat shows metadata IO statistics only, which has been > > confusing to users. > > > > Add iostat support to the DAX read/write path. > > > > Note, iostat still does not support the DAX mmap path as it allows > > user applications to access directly. > > > > Signed-off-by: Toshi Kani <toshi.kani@hpe.com> > > Cc: Andrew Morton <akpm@linux-foundation.org> > > Cc: Alexander Viro <viro@zeniv.linux.org.uk> > > Cc: Dan Williams <dan.j.williams@intel.com> > > Cc: Ross Zwisler <ross.zwisler@linux.intel.com> > > --- > > fs/dax.c | 37 +++++++++++++++++++++++++++++++++++++ > > 1 file changed, 37 insertions(+) > > > > diff --git a/fs/dax.c b/fs/dax.c > > index 014defd..3aaaac2 100644 > > --- a/fs/dax.c > > +++ b/fs/dax.c > > @@ -144,6 +144,34 @@ static sector_t to_sector(const struct > > buffer_head *bh, > > return sector; > > } > > > > +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; > > Should this be a minimum of one sector since we allow unaligned > transfers through this interface? > > ...or is iov_iter_count() somehow guaranteed to be sector aligned > here?
You are right. I will update to set a minimum of one sector in v2.
Thanks! -Toshi |  |