Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Wed, Dec 21, 2016 at 1:24 PM, Dave Chinner wrote: > On Wed, Dec 21, 2016 at 08:53:46AM -0800, Dan Williams wrote: >> On Tue, Dec 20, 2016 at 4:40 PM, Darrick J. Wong >> wrote: >> > On Mon, Dec 19, 2016 at 05:18:40PM -0800, Dan Williams wrote: >>

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Wed, Dec 21, 2016 at 1:24 PM, Dave Chinner wrote: > On Wed, Dec 21, 2016 at 08:53:46AM -0800, Dan Williams wrote: >> On Tue, Dec 20, 2016 at 4:40 PM, Darrick J. Wong >> wrote: >> > On Mon, Dec 19, 2016 at 05:18:40PM -0800, Dan Williams wrote: >> >> On Mon, Dec 19, 2016 at 5:09 PM, Darrick J.

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Wed, Dec 21, 2016 at 08:53:46AM -0800, Dan Williams wrote: > On Tue, Dec 20, 2016 at 4:40 PM, Darrick J. Wong > wrote: > > On Mon, Dec 19, 2016 at 05:18:40PM -0800, Dan Williams wrote: > >> On Mon, Dec 19, 2016 at 5:09 PM, Darrick J. Wong > >>

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Wed, Dec 21, 2016 at 08:53:46AM -0800, Dan Williams wrote: > On Tue, Dec 20, 2016 at 4:40 PM, Darrick J. Wong > wrote: > > On Mon, Dec 19, 2016 at 05:18:40PM -0800, Dan Williams wrote: > >> On Mon, Dec 19, 2016 at 5:09 PM, Darrick J. Wong > >> wrote: > >> > On Mon, Dec 19, 2016 at 02:11:49PM

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Tue, Dec 20, 2016 at 4:40 PM, Darrick J. Wong wrote: > On Mon, Dec 19, 2016 at 05:18:40PM -0800, Dan Williams wrote: >> On Mon, Dec 19, 2016 at 5:09 PM, Darrick J. Wong >> wrote: >> > On Mon, Dec 19, 2016 at 02:11:49PM -0700, Ross Zwisler

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Tue, Dec 20, 2016 at 4:40 PM, Darrick J. Wong wrote: > On Mon, Dec 19, 2016 at 05:18:40PM -0800, Dan Williams wrote: >> On Mon, Dec 19, 2016 at 5:09 PM, Darrick J. Wong >> wrote: >> > On Mon, Dec 19, 2016 at 02:11:49PM -0700, Ross Zwisler wrote: >> >> On Fri, Sep 16, 2016 at 03:54:05PM +1000,

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, Dec 19, 2016 at 05:18:40PM -0800, Dan Williams wrote: > On Mon, Dec 19, 2016 at 5:09 PM, Darrick J. Wong > wrote: > > On Mon, Dec 19, 2016 at 02:11:49PM -0700, Ross Zwisler wrote: > >> On Fri, Sep 16, 2016 at 03:54:05PM +1000, Nicholas Piggin wrote: > >> <> > >> >

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, Dec 19, 2016 at 05:18:40PM -0800, Dan Williams wrote: > On Mon, Dec 19, 2016 at 5:09 PM, Darrick J. Wong > wrote: > > On Mon, Dec 19, 2016 at 02:11:49PM -0700, Ross Zwisler wrote: > >> On Fri, Sep 16, 2016 at 03:54:05PM +1000, Nicholas Piggin wrote: > >> <> > >> > Definitely the first

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, Dec 19, 2016 at 5:09 PM, Darrick J. Wong wrote: > On Mon, Dec 19, 2016 at 02:11:49PM -0700, Ross Zwisler wrote: >> On Fri, Sep 16, 2016 at 03:54:05PM +1000, Nicholas Piggin wrote: >> <> >> > Definitely the first step would be your simple preallocated per >> >

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, Dec 19, 2016 at 5:09 PM, Darrick J. Wong wrote: > On Mon, Dec 19, 2016 at 02:11:49PM -0700, Ross Zwisler wrote: >> On Fri, Sep 16, 2016 at 03:54:05PM +1000, Nicholas Piggin wrote: >> <> >> > Definitely the first step would be your simple preallocated per >> > inode approach until it is

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, Dec 19, 2016 at 02:11:49PM -0700, Ross Zwisler wrote: > On Fri, Sep 16, 2016 at 03:54:05PM +1000, Nicholas Piggin wrote: > <> > > Definitely the first step would be your simple preallocated per > > inode approach until it is shown to be insufficient. > > Reviving this thread a few months

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, Dec 19, 2016 at 02:11:49PM -0700, Ross Zwisler wrote: > On Fri, Sep 16, 2016 at 03:54:05PM +1000, Nicholas Piggin wrote: > <> > > Definitely the first step would be your simple preallocated per > > inode approach until it is shown to be insufficient. > > Reviving this thread a few months

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Fri, Sep 16, 2016 at 03:54:05PM +1000, Nicholas Piggin wrote: <> > Definitely the first step would be your simple preallocated per > inode approach until it is shown to be insufficient. Reviving this thread a few months later... Dave, we're interested in taking a serious look at what it would

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Fri, Sep 16, 2016 at 03:54:05PM +1000, Nicholas Piggin wrote: <> > Definitely the first step would be your simple preallocated per > inode approach until it is shown to be insufficient. Reviving this thread a few months later... Dave, we're interested in taking a serious look at what it would

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Fri, 16 Sep 2016 08:33:50 +1000 Dave Chinner wrote: > On Thu, Sep 15, 2016 at 09:42:22PM +1000, Nicholas Piggin wrote: > > On Thu, 15 Sep 2016 20:32:10 +1000 > > Dave Chinner wrote: > > > > > > You still haven't described anything about what a

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Fri, 16 Sep 2016 08:33:50 +1000 Dave Chinner wrote: > On Thu, Sep 15, 2016 at 09:42:22PM +1000, Nicholas Piggin wrote: > > On Thu, 15 Sep 2016 20:32:10 +1000 > > Dave Chinner wrote: > > > > > > You still haven't described anything about what a per-block flag > > > design is supposed to

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Thu, Sep 15, 2016 at 09:42:22PM +1000, Nicholas Piggin wrote: > On Thu, 15 Sep 2016 20:32:10 +1000 > Dave Chinner wrote: > > > > You still haven't described anything about what a per-block flag > > design is supposed to look like :/ > > For the API, or

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Thu, Sep 15, 2016 at 09:42:22PM +1000, Nicholas Piggin wrote: > On Thu, 15 Sep 2016 20:32:10 +1000 > Dave Chinner wrote: > > > > You still haven't described anything about what a per-block flag > > design is supposed to look like :/ > > For the API, or implementation? I'm not quite sure

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Thu, 15 Sep 2016 20:32:10 +1000 Dave Chinner wrote: > On Thu, Sep 15, 2016 at 01:49:45PM +1000, Nicholas Piggin wrote: > > On Thu, 15 Sep 2016 12:31:33 +1000 > > Dave Chinner wrote: > > > > > On Wed, Sep 14, 2016 at 08:19:36PM +1000, Nicholas

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Thu, 15 Sep 2016 20:32:10 +1000 Dave Chinner wrote: > On Thu, Sep 15, 2016 at 01:49:45PM +1000, Nicholas Piggin wrote: > > On Thu, 15 Sep 2016 12:31:33 +1000 > > Dave Chinner wrote: > > > > > On Wed, Sep 14, 2016 at 08:19:36PM +1000, Nicholas Piggin wrote: > > > > On Wed, 14 Sep 2016

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Thu, Sep 15, 2016 at 01:49:45PM +1000, Nicholas Piggin wrote: > On Thu, 15 Sep 2016 12:31:33 +1000 > Dave Chinner wrote: > > > On Wed, Sep 14, 2016 at 08:19:36PM +1000, Nicholas Piggin wrote: > > > On Wed, 14 Sep 2016 17:39:02 +1000 > > Sure, but one first has to describe

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Thu, Sep 15, 2016 at 01:49:45PM +1000, Nicholas Piggin wrote: > On Thu, 15 Sep 2016 12:31:33 +1000 > Dave Chinner wrote: > > > On Wed, Sep 14, 2016 at 08:19:36PM +1000, Nicholas Piggin wrote: > > > On Wed, 14 Sep 2016 17:39:02 +1000 > > Sure, but one first has to describe the feature desired

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Wed, Sep 14, 2016 at 10:55:03PM -0700, Darrick J. Wong wrote: > On Mon, Sep 12, 2016 at 11:40:35AM +1000, Dave Chinner wrote: > > On Thu, Sep 08, 2016 at 04:56:36PM -0600, Ross Zwisler wrote: > > > On Wed, Sep 07, 2016 at 09:32:36PM -0700, Dan Williams wrote: > > > > My understanding is that it

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Wed, Sep 14, 2016 at 10:55:03PM -0700, Darrick J. Wong wrote: > On Mon, Sep 12, 2016 at 11:40:35AM +1000, Dave Chinner wrote: > > On Thu, Sep 08, 2016 at 04:56:36PM -0600, Ross Zwisler wrote: > > > On Wed, Sep 07, 2016 at 09:32:36PM -0700, Dan Williams wrote: > > > > My understanding is that it

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, Sep 12, 2016 at 11:40:35AM +1000, Dave Chinner wrote: > On Thu, Sep 08, 2016 at 04:56:36PM -0600, Ross Zwisler wrote: > > On Wed, Sep 07, 2016 at 09:32:36PM -0700, Dan Williams wrote: > > > My understanding is that it is looking for the VM_MIXEDMAP flag which > > > is already ambiguous for

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, Sep 12, 2016 at 11:40:35AM +1000, Dave Chinner wrote: > On Thu, Sep 08, 2016 at 04:56:36PM -0600, Ross Zwisler wrote: > > On Wed, Sep 07, 2016 at 09:32:36PM -0700, Dan Williams wrote: > > > My understanding is that it is looking for the VM_MIXEDMAP flag which > > > is already ambiguous for

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Thu, 15 Sep 2016 12:31:33 +1000 Dave Chinner wrote: > On Wed, Sep 14, 2016 at 08:19:36PM +1000, Nicholas Piggin wrote: > > On Wed, 14 Sep 2016 17:39:02 +1000 > > Dave Chinner wrote: > > > Ok, looking back over your example, you seem to be

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Thu, 15 Sep 2016 12:31:33 +1000 Dave Chinner wrote: > On Wed, Sep 14, 2016 at 08:19:36PM +1000, Nicholas Piggin wrote: > > On Wed, 14 Sep 2016 17:39:02 +1000 > > Dave Chinner wrote: > > > Ok, looking back over your example, you seem to be suggesting a new > > > page fault behaviour is

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Wed, Sep 14, 2016 at 08:19:36PM +1000, Nicholas Piggin wrote: > On Wed, 14 Sep 2016 17:39:02 +1000 > Dave Chinner wrote: > > Ok, looking back over your example, you seem to be suggesting a new > > page fault behaviour is required from filesystems that has not been > >

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Wed, Sep 14, 2016 at 08:19:36PM +1000, Nicholas Piggin wrote: > On Wed, 14 Sep 2016 17:39:02 +1000 > Dave Chinner wrote: > > Ok, looking back over your example, you seem to be suggesting a new > > page fault behaviour is required from filesystems that has not been > > described or explained,

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Wed, 14 Sep 2016 17:39:02 +1000 Dave Chinner wrote: > On Tue, Sep 13, 2016 at 11:53:11AM +1000, Nicholas Piggin wrote: > > On Tue, 13 Sep 2016 07:34:36 +1000 > > Dave Chinner wrote: > > But let me understand your example in the absence of that. > >

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Wed, 14 Sep 2016 17:39:02 +1000 Dave Chinner wrote: > On Tue, Sep 13, 2016 at 11:53:11AM +1000, Nicholas Piggin wrote: > > On Tue, 13 Sep 2016 07:34:36 +1000 > > Dave Chinner wrote: > > But let me understand your example in the absence of that. > > > > - Application mmaps a file, faults in

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Tue, Sep 13, 2016 at 11:53:11AM +1000, Nicholas Piggin wrote: > On Tue, 13 Sep 2016 07:34:36 +1000 > Dave Chinner wrote: > But let me understand your example in the absence of that. > > - Application mmaps a file, faults in block 0 > - FS allocates block, creates

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Tue, Sep 13, 2016 at 11:53:11AM +1000, Nicholas Piggin wrote: > On Tue, 13 Sep 2016 07:34:36 +1000 > Dave Chinner wrote: > But let me understand your example in the absence of that. > > - Application mmaps a file, faults in block 0 > - FS allocates block, creates mappings, syncs metadata,

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Tue, 13 Sep 2016 00:17:32 -0700 Christoph Hellwig wrote: > On Tue, Sep 13, 2016 at 11:53:11AM +1000, Nicholas Piggin wrote: > > - Application mmaps a file, faults in block 0 > > - FS allocates block, creates mappings, syncs metadata, sets "no fsync" > > flag for that

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Tue, 13 Sep 2016 00:17:32 -0700 Christoph Hellwig wrote: > On Tue, Sep 13, 2016 at 11:53:11AM +1000, Nicholas Piggin wrote: > > - Application mmaps a file, faults in block 0 > > - FS allocates block, creates mappings, syncs metadata, sets "no fsync" > > flag for that block, and completes

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Tue, Sep 13, 2016 at 11:53:11AM +1000, Nicholas Piggin wrote: > - Application mmaps a file, faults in block 0 > - FS allocates block, creates mappings, syncs metadata, sets "no fsync" > flag for that block, and completes the fault. > - Application writes some data to block 0, completes

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Tue, Sep 13, 2016 at 11:53:11AM +1000, Nicholas Piggin wrote: > - Application mmaps a file, faults in block 0 > - FS allocates block, creates mappings, syncs metadata, sets "no fsync" > flag for that block, and completes the fault. > - Application writes some data to block 0, completes

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, 12 Sep 2016 21:06:49 -0700 Dan Williams wrote: > On Mon, Sep 12, 2016 at 6:31 PM, Nicholas Piggin wrote: > > On Mon, 12 Sep 2016 08:01:48 -0700 > [..] > > That said, a noop system call is on the order of 100 cycles nowadays, > > so rushing

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, 12 Sep 2016 21:06:49 -0700 Dan Williams wrote: > On Mon, Sep 12, 2016 at 6:31 PM, Nicholas Piggin wrote: > > On Mon, 12 Sep 2016 08:01:48 -0700 > [..] > > That said, a noop system call is on the order of 100 cycles nowadays, > > so rushing to implement these APIs without seeing good

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, Sep 12, 2016 at 6:31 PM, Nicholas Piggin wrote: > On Mon, 12 Sep 2016 08:01:48 -0700 [..] > That said, a noop system call is on the order of 100 cycles nowadays, > so rushing to implement these APIs without seeing good numbers and > actual users ready to go seems

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, Sep 12, 2016 at 6:31 PM, Nicholas Piggin wrote: > On Mon, 12 Sep 2016 08:01:48 -0700 [..] > That said, a noop system call is on the order of 100 cycles nowadays, > so rushing to implement these APIs without seeing good numbers and > actual users ready to go seems premature. *This* is the

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Tue, 13 Sep 2016 07:34:36 +1000 Dave Chinner wrote: > On Mon, Sep 12, 2016 at 06:05:07PM +1000, Nicholas Piggin wrote: > > On Mon, 12 Sep 2016 00:51:28 -0700 > > Christoph Hellwig wrote: > > > > > On Mon, Sep 12, 2016 at 05:25:15PM +1000, Oliver

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Tue, 13 Sep 2016 07:34:36 +1000 Dave Chinner wrote: > On Mon, Sep 12, 2016 at 06:05:07PM +1000, Nicholas Piggin wrote: > > On Mon, 12 Sep 2016 00:51:28 -0700 > > Christoph Hellwig wrote: > > > > > On Mon, Sep 12, 2016 at 05:25:15PM +1000, Oliver O'Halloran wrote: > > > > What are the

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, 12 Sep 2016 08:01:48 -0700 Christoph Hellwig wrote: > On Mon, Sep 12, 2016 at 06:05:07PM +1000, Nicholas Piggin wrote: > > It's not fundamentally broken, it just doesn't fit well existing > > filesystems. > > Or the existing file system architecture for that

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, 12 Sep 2016 08:01:48 -0700 Christoph Hellwig wrote: > On Mon, Sep 12, 2016 at 06:05:07PM +1000, Nicholas Piggin wrote: > > It's not fundamentally broken, it just doesn't fit well existing > > filesystems. > > Or the existing file system architecture for that matter. Which makes > it

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, Sep 12, 2016 at 06:05:07PM +1000, Nicholas Piggin wrote: > On Mon, 12 Sep 2016 00:51:28 -0700 > Christoph Hellwig wrote: > > > On Mon, Sep 12, 2016 at 05:25:15PM +1000, Oliver O'Halloran wrote: > > > What are the problems here? Is this a matter of existing filesystems

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, Sep 12, 2016 at 06:05:07PM +1000, Nicholas Piggin wrote: > On Mon, 12 Sep 2016 00:51:28 -0700 > Christoph Hellwig wrote: > > > On Mon, Sep 12, 2016 at 05:25:15PM +1000, Oliver O'Halloran wrote: > > > What are the problems here? Is this a matter of existing filesystems > > > being

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, Sep 12, 2016 at 06:05:07PM +1000, Nicholas Piggin wrote: > It's not fundamentally broken, it just doesn't fit well existing > filesystems. Or the existing file system architecture for that matter. Which makes it a fundamentally broken model. > Dave's post of requirements is also wrong.

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, Sep 12, 2016 at 06:05:07PM +1000, Nicholas Piggin wrote: > It's not fundamentally broken, it just doesn't fit well existing > filesystems. Or the existing file system architecture for that matter. Which makes it a fundamentally broken model. > Dave's post of requirements is also wrong.

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, 12 Sep 2016 00:51:28 -0700 Christoph Hellwig wrote: > On Mon, Sep 12, 2016 at 05:25:15PM +1000, Oliver O'Halloran wrote: > > What are the problems here? Is this a matter of existing filesystems > > being unable/unwilling to support this or is it just fundamentally > >

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, 12 Sep 2016 00:51:28 -0700 Christoph Hellwig wrote: > On Mon, Sep 12, 2016 at 05:25:15PM +1000, Oliver O'Halloran wrote: > > What are the problems here? Is this a matter of existing filesystems > > being unable/unwilling to support this or is it just fundamentally > > broken? > > It's

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, Sep 12, 2016 at 05:25:15PM +1000, Oliver O'Halloran wrote: > What are the problems here? Is this a matter of existing filesystems > being unable/unwilling to support this or is it just fundamentally > broken? It's a fundamentally broken model. See Dave's post that actually was sent

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, Sep 12, 2016 at 05:25:15PM +1000, Oliver O'Halloran wrote: > What are the problems here? Is this a matter of existing filesystems > being unable/unwilling to support this or is it just fundamentally > broken? It's a fundamentally broken model. See Dave's post that actually was sent

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, Sep 12, 2016 at 3:27 PM, Christoph Hellwig wrote: > On Thu, Sep 08, 2016 at 04:56:36PM -0600, Ross Zwisler wrote: >> I think this goes back to our previous discussion about support for the PMEM >> programming model. Really I think what NVML needs isn't a way to tell

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Mon, Sep 12, 2016 at 3:27 PM, Christoph Hellwig wrote: > On Thu, Sep 08, 2016 at 04:56:36PM -0600, Ross Zwisler wrote: >> I think this goes back to our previous discussion about support for the PMEM >> programming model. Really I think what NVML needs isn't a way to tell if it >> is getting a

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On 09/12/2016 11:44 AM, Rudoff, Andy wrote: Whether msync/fsync can make data persistent depends on ADR feature on memory controller, if it exists everything works well, otherwise, we need to have another interface that is why 'Flush hint table' in ACPI comes in. 'Flush hint table' is

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On 09/12/2016 11:44 AM, Rudoff, Andy wrote: Whether msync/fsync can make data persistent depends on ADR feature on memory controller, if it exists everything works well, otherwise, we need to have another interface that is why 'Flush hint table' in ACPI comes in. 'Flush hint table' is

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On 09/09/2016 11:40 PM, Dan Williams wrote: On Fri, Sep 9, 2016 at 1:55 AM, Xiao Guangrong wrote: [..] Whether a persistent memory mapping requires an msync/fsync is a filesystem specific question. This mincore proposal is separate from that. Consider

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On 09/09/2016 11:40 PM, Dan Williams wrote: On Fri, Sep 9, 2016 at 1:55 AM, Xiao Guangrong wrote: [..] Whether a persistent memory mapping requires an msync/fsync is a filesystem specific question. This mincore proposal is separate from that. Consider device-DAX for volatile memory or

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Thu, Sep 08, 2016 at 04:56:36PM -0600, Ross Zwisler wrote: > I think this goes back to our previous discussion about support for the PMEM > programming model. Really I think what NVML needs isn't a way to tell if it > is getting a DAX mapping, but whether it is getting a DAX mapping on a >

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Thu, Sep 08, 2016 at 04:56:36PM -0600, Ross Zwisler wrote: > I think this goes back to our previous discussion about support for the PMEM > programming model. Really I think what NVML needs isn't a way to tell if it > is getting a DAX mapping, but whether it is getting a DAX mapping on a >

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

>Whether msync/fsync can make data persistent depends on ADR feature on >memory controller, if it exists everything works well, otherwise, we need >to have another interface that is why 'Flush hint table' in ACPI comes >in. 'Flush hint table' is particularly useful for nvdimm virtualization if >we

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

>Whether msync/fsync can make data persistent depends on ADR feature on >memory controller, if it exists everything works well, otherwise, we need >to have another interface that is why 'Flush hint table' in ACPI comes >in. 'Flush hint table' is particularly useful for nvdimm virtualization if >we

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Thu, Sep 08, 2016 at 04:56:36PM -0600, Ross Zwisler wrote: > On Wed, Sep 07, 2016 at 09:32:36PM -0700, Dan Williams wrote: > > My understanding is that it is looking for the VM_MIXEDMAP flag which > > is already ambiguous for determining if DAX is enabled even if this > > dynamic listing issue

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Thu, Sep 08, 2016 at 04:56:36PM -0600, Ross Zwisler wrote: > On Wed, Sep 07, 2016 at 09:32:36PM -0700, Dan Williams wrote: > > My understanding is that it is looking for the VM_MIXEDMAP flag which > > is already ambiguous for determining if DAX is enabled even if this > > dynamic listing issue

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Fri, Sep 9, 2016 at 1:55 AM, Xiao Guangrong wrote: [..] >> >> Whether a persistent memory mapping requires an msync/fsync is a >> filesystem specific question. This mincore proposal is separate from >> that. Consider device-DAX for volatile memory or mincore()

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Fri, Sep 9, 2016 at 1:55 AM, Xiao Guangrong wrote: [..] >> >> Whether a persistent memory mapping requires an msync/fsync is a >> filesystem specific question. This mincore proposal is separate from >> that. Consider device-DAX for volatile memory or mincore() called on >> an anonymous

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On 09/09/2016 07:04 AM, Dan Williams wrote: On Thu, Sep 8, 2016 at 3:56 PM, Ross Zwisler wrote: On Wed, Sep 07, 2016 at 09:32:36PM -0700, Dan Williams wrote: [ adding linux-fsdevel and linux-nvdimm ] On Wed, Sep 7, 2016 at 8:36 PM, Xiao Guangrong

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On 09/09/2016 07:04 AM, Dan Williams wrote: On Thu, Sep 8, 2016 at 3:56 PM, Ross Zwisler wrote: On Wed, Sep 07, 2016 at 09:32:36PM -0700, Dan Williams wrote: [ adding linux-fsdevel and linux-nvdimm ] On Wed, Sep 7, 2016 at 8:36 PM, Xiao Guangrong wrote: [..] However, it is not easy to

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Thu, Sep 8, 2016 at 3:56 PM, Ross Zwisler wrote: > On Wed, Sep 07, 2016 at 09:32:36PM -0700, Dan Williams wrote: >> [ adding linux-fsdevel and linux-nvdimm ] >> >> On Wed, Sep 7, 2016 at 8:36 PM, Xiao Guangrong >> wrote: >> [..] >>

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Thu, Sep 8, 2016 at 3:56 PM, Ross Zwisler wrote: > On Wed, Sep 07, 2016 at 09:32:36PM -0700, Dan Williams wrote: >> [ adding linux-fsdevel and linux-nvdimm ] >> >> On Wed, Sep 7, 2016 at 8:36 PM, Xiao Guangrong >> wrote: >> [..] >> > However, it is not easy to handle the case that the new VMA

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Wed, Sep 07, 2016 at 09:32:36PM -0700, Dan Williams wrote: > [ adding linux-fsdevel and linux-nvdimm ] > > On Wed, Sep 7, 2016 at 8:36 PM, Xiao Guangrong > wrote: > [..] > > However, it is not easy to handle the case that the new VMA overlays with > > the old

Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

On Wed, Sep 07, 2016 at 09:32:36PM -0700, Dan Williams wrote: > [ adding linux-fsdevel and linux-nvdimm ] > > On Wed, Sep 7, 2016 at 8:36 PM, Xiao Guangrong > wrote: > [..] > > However, it is not easy to handle the case that the new VMA overlays with > > the old VMA > > already got by userspace.

DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

[ adding linux-fsdevel and linux-nvdimm ] On Wed, Sep 7, 2016 at 8:36 PM, Xiao Guangrong wrote: [..] > However, it is not easy to handle the case that the new VMA overlays with > the old VMA > already got by userspace. I think we have some choices: > 1: One way is

DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)

[ adding linux-fsdevel and linux-nvdimm ] On Wed, Sep 7, 2016 at 8:36 PM, Xiao Guangrong wrote: [..] > However, it is not easy to handle the case that the new VMA overlays with > the old VMA > already got by userspace. I think we have some choices: > 1: One way is completely skipping the new VMA