On Fri 27-10-17 02:47:43, Du, Fan wrote: > > > >-----Original Message----- > >From: Hansen, Dave > >Sent: Thursday, October 26, 2017 10:03 PM > >To: Du, Fan <fan...@intel.com>; a...@linux-foundation.org; h...@lst.de; > >Williams, Dan J <dan.j.willi...@intel.com>; mho...@kernel.org > >Cc: linux-kernel@vger.kernel.org > >Subject: Re: [PATCH v4] Add /proc/PID/smaps support for DAX > > > >I'm honestly not understanding what problem this solves. Could you, > >perhaps, do a before and after of smaps with and without this patch? > > The motivation here is described in the commit message. > ------------------------------------------------------------------------------------------ > Memory behind device DAX is not attached into normal memory > management system, when user mmap /dev/dax, smaps part is > currently missing, so no idea for user to check how much > device DAX memory are actually used in practice.
This might be motivation but you are still not explaining _why_ that is a problem. _Who_ is going to use that information and for _what_ purpose. This is really essential! -- Michal Hocko SUSE Labs
