From: Jerome Glisse <j.glisse@gmail.com>
To: Mark Hairgrove <mhairgrove@nvidia.com>
Cc: "akpm@linux-foundation.org" <akpm@linux-foundation.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"linux-mm@kvack.org" <linux-mm@kvack.org>,
"Linus Torvalds" <torvalds@linux-foundation.org>,
"joro@8bytes.org" <joro@8bytes.org>,
"Mel Gorman" <mgorman@suse.de>, "H. Peter Anvin" <hpa@zytor.com>,
"Peter Zijlstra" <peterz@infradead.org>,
"Andrea Arcangeli" <aarcange@redhat.com>,
"Johannes Weiner" <jweiner@redhat.com>,
"Larry Woodman" <lwoodman@redhat.com>,
"Rik van Riel" <riel@redhat.com>,
"Dave Airlie" <airlied@redhat.com>,
"Brendan Conoboy" <blc@redhat.com>,
"Joe Donohue" <jdonohue@redhat.com>,
"Duncan Poole" <dpoole@nvidia.com>,
"Sherry Cheung" <SCheung@nvidia.com>,
"Subhash Gutti" <sgutti@nvidia.com>,
"John Hubbard" <jhubbard@nvidia.com>,
"Lucien Dunning" <ldunning@nvidia.com>,
"Cameron Buschardt" <cabuschardt@nvidia.com>,
"Arvind Gopalakrishnan" <arvindg@nvidia.com>,
"Haggai Eran" <haggaie@mellanox.com>,
"Shachar Raindel" <raindel@mellanox.com>,
"Liran Liss" <liranl@mellanox.com>,
"Roland Dreier" <roland@purestorage.com>,
"Ben Sander" <ben.sander@amd.com>,
"Greg Stoner" <Greg.Stoner@amd.com>,
"John Bridgman" <John.Bridgman@amd.com>,
"Michael Mantor" <Michael.Mantor@amd.com>,
"Paul Blinzer" <Paul.Blinzer@amd.com>,
"Laurent Morichetti" <Laurent.Morichetti@amd.com>,
"Alexander Deucher" <Alexander.Deucher@amd.com>,
"Oded Gabbay" <Oded.Gabbay@amd.com>,
"Jérôme Glisse" <jglisse@redhat.com>,
"Jatin Kumar" <jakumar@nvidia.com>
Subject: Re: [PATCH 07/36] HMM: add per mirror page table v3.
Date: Mon, 29 Jun 2015 10:50:54 -0400 [thread overview]
Message-ID: <20150629145053.GB2173@gmail.com> (raw)
In-Reply-To: <alpine.DEB.2.00.1506261958010.22464@mdh-linux64-2.nvidia.com>
On Fri, Jun 26, 2015 at 08:02:03PM -0700, Mark Hairgrove wrote:
> On Fri, 26 Jun 2015, Jerome Glisse wrote:
> > On Thu, Jun 25, 2015 at 04:05:48PM -0700, Mark Hairgrove wrote:
> > > On Thu, 21 May 2015, j.glisse@gmail.com wrote:
> > > > From: Jerome Glisse <jglisse@redhat.com>
> > > > [...]
> > > >
> > > > + /* update() - update device mmu following an event.
> > > > + *
> > > > + * @mirror: The mirror that link process address space with the device.
> > > > + * @event: The event that triggered the update.
> > > > + * Returns: 0 on success or error code {-EIO, -ENOMEM}.
> > > > + *
> > > > + * Called to update device page table for a range of address.
> > > > + * The event type provide the nature of the update :
> > > > + * - Range is no longer valid (munmap).
> > > > + * - Range protection changes (mprotect, COW, ...).
> > > > + * - Range is unmapped (swap, reclaim, page migration, ...).
> > > > + * - Device page fault.
> > > > + * - ...
> > > > + *
> > > > + * Thought most device driver only need to use pte_mask as it reflects
> > > > + * change that will happen to the HMM page table ie :
> > > > + * new_pte = old_pte & event->pte_mask;
> > >
> > > Documentation request: It would be useful to break down exactly what is
> > > required from the driver for each event type here, and what extra
> > > information is provided by the type that isn't provided by the pte_mask.
> >
> > Mostly event tell you if you need to free or not the device page table for
> > the range, which is not something you can infer from the pte_mask reliably.
> > Difference btw migration and munmap for instance, same pte_mask but range
> > is still valid in the migration case it will just be backed by a new set of
> > pages.
>
> Given that event->pte_mask and event->type provide redundant information,
> are they both necessary?
Like said, you can not infer event->type from pte_mask but you can infer
pte_mask from event->type. The idea is behind providing pte_mask is that
simple driver can just use that with the iter walk and simply mask the HMM
page table entry they read ((*ptep) & pte_mask) to repopulate the device
page table.
So yes pte_mask is redundant but i think it will be useful for a range of
device driver.
Cheers,
Jerome
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2015-06-29 14:51 UTC|newest]
Thread overview: 79+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-05-21 19:31 HMM (Heterogeneous Memory Management) v8 j.glisse
2015-05-21 19:31 ` [PATCH 01/36] mmu_notifier: add event information to address invalidation v7 j.glisse
2015-05-30 3:43 ` John Hubbard
2015-06-01 19:03 ` Jerome Glisse
2015-06-01 23:10 ` John Hubbard
2015-06-03 16:07 ` Jerome Glisse
2015-06-03 23:02 ` John Hubbard
2015-05-21 19:31 ` [PATCH 02/36] mmu_notifier: keep track of active invalidation ranges v3 j.glisse
2015-05-27 5:09 ` Aneesh Kumar K.V
2015-05-27 14:32 ` Jerome Glisse
2015-06-02 9:32 ` John Hubbard
2015-06-03 17:15 ` Jerome Glisse
2015-06-05 3:29 ` John Hubbard
2015-05-21 19:31 ` [PATCH 03/36] mmu_notifier: pass page pointer to mmu_notifier_invalidate_page() j.glisse
2015-05-27 5:17 ` Aneesh Kumar K.V
2015-05-27 14:33 ` Jerome Glisse
2015-06-03 4:25 ` John Hubbard
2015-05-21 19:31 ` [PATCH 04/36] mmu_notifier: allow range invalidation to exclude a specific mmu_notifier j.glisse
2015-05-21 19:31 ` [PATCH 05/36] HMM: introduce heterogeneous memory management v3 j.glisse
2015-05-27 5:50 ` Aneesh Kumar K.V
2015-05-27 14:38 ` Jerome Glisse
2015-06-08 19:40 ` Mark Hairgrove
2015-06-08 21:17 ` Jerome Glisse
2015-06-09 1:54 ` Mark Hairgrove
2015-06-09 15:56 ` Jerome Glisse
2015-06-10 3:33 ` Mark Hairgrove
2015-06-10 15:42 ` Jerome Glisse
2015-06-11 1:15 ` Mark Hairgrove
2015-06-11 14:23 ` Jerome Glisse
2015-06-11 22:26 ` Mark Hairgrove
2015-06-15 14:32 ` Jerome Glisse
2015-05-21 19:31 ` [PATCH 06/36] HMM: add HMM page table v2 j.glisse
2015-06-19 2:06 ` Mark Hairgrove
2015-06-19 18:07 ` Jerome Glisse
2015-06-20 2:34 ` Mark Hairgrove
2015-06-25 22:57 ` Mark Hairgrove
2015-06-26 16:30 ` Jerome Glisse
2015-06-27 1:34 ` Mark Hairgrove
2015-06-29 14:43 ` Jerome Glisse
2015-07-01 2:51 ` Mark Hairgrove
2015-07-01 15:07 ` Jerome Glisse
2015-05-21 19:31 ` [PATCH 07/36] HMM: add per mirror page table v3 j.glisse
2015-06-25 23:05 ` Mark Hairgrove
2015-06-26 16:43 ` Jerome Glisse
2015-06-27 3:02 ` Mark Hairgrove
2015-06-29 14:50 ` Jerome Glisse [this message]
2015-05-21 19:31 ` [PATCH 08/36] HMM: add device page fault support v3 j.glisse
2015-05-21 19:31 ` [PATCH 09/36] HMM: add mm page table iterator helpers j.glisse
2015-05-21 19:31 ` [PATCH 10/36] HMM: use CPU page table during invalidation j.glisse
2015-05-21 19:31 ` [PATCH 11/36] HMM: add discard range helper (to clear and free resources for a range) j.glisse
2015-05-21 19:31 ` [PATCH 12/36] HMM: add dirty range helper (to toggle dirty bit inside mirror page table) j.glisse
2015-05-21 19:31 ` [PATCH 13/36] HMM: DMA map memory on behalf of device driver j.glisse
2015-05-21 19:31 ` [PATCH 14/36] fork: pass the dst vma to copy_page_range() and its sub-functions j.glisse
2015-05-21 19:31 ` [PATCH 15/36] memcg: export get_mem_cgroup_from_mm() j.glisse
2015-05-21 19:31 ` [PATCH 16/36] HMM: add special swap filetype for memory migrated to HMM device memory j.glisse
2015-06-24 7:49 ` Haggai Eran
2015-05-21 19:31 ` [PATCH 17/36] HMM: add new HMM page table flag (valid device memory) j.glisse
2015-05-21 19:31 ` [PATCH 18/36] HMM: add new HMM page table flag (select flag) j.glisse
2015-05-21 19:31 ` [PATCH 19/36] HMM: handle HMM device page table entry on mirror page table fault and update j.glisse
2015-05-21 20:22 ` [PATCH 20/36] HMM: mm add helper to update page table when migrating memory back jglisse
2015-05-21 20:22 ` [PATCH 21/36] HMM: mm add helper to update page table when migrating memory jglisse
2015-05-21 20:22 ` [PATCH 22/36] HMM: add new callback for copying memory from and to device memory jglisse
2015-05-21 20:22 ` [PATCH 23/36] HMM: allow to get pointer to spinlock protecting a directory jglisse
2015-05-21 20:23 ` [PATCH 24/36] HMM: split DMA mapping function in two jglisse
2015-05-21 20:23 ` [PATCH 25/36] HMM: add helpers for migration back to system memory jglisse
2015-05-21 20:23 ` [PATCH 26/36] HMM: fork copy migrated memory into system memory for child process jglisse
2015-05-21 20:23 ` [PATCH 27/36] HMM: CPU page fault on migrated memory jglisse
2015-05-21 20:23 ` [PATCH 28/36] HMM: add mirror fault support for system to device memory migration jglisse
2015-05-21 20:23 ` [PATCH 29/36] IB/mlx5: add a new paramter to __mlx_ib_populated_pas for ODP with HMM jglisse
2015-05-21 20:23 ` [PATCH 30/36] IB/mlx5: add a new paramter to mlx5_ib_update_mtt() " jglisse
2015-05-21 20:23 ` [PATCH 31/36] IB/odp: export rbt_ib_umem_for_each_in_range() jglisse
2015-05-21 20:23 ` [PATCH 32/36] IB/odp/hmm: add new kernel option to use HMM for ODP jglisse
2015-05-21 20:23 ` [PATCH 33/36] IB/odp/hmm: add core infiniband structure and helper for ODP with HMM jglisse
2015-06-24 13:59 ` Haggai Eran
2015-05-21 20:23 ` [PATCH 34/36] IB/mlx5/hmm: add mlx5 HMM device initialization and callback jglisse
2015-05-21 20:23 ` [PATCH 35/36] IB/mlx5/hmm: add page fault support for ODP on HMM jglisse
2015-05-21 20:23 ` [PATCH 36/36] IB/mlx5/hmm: enable ODP using HMM jglisse
2015-05-30 3:01 ` HMM (Heterogeneous Memory Management) v8 John Hubbard
2015-05-31 6:56 ` Haggai Eran
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20150629145053.GB2173@gmail.com \
--to=j.glisse@gmail.com \
--cc=Alexander.Deucher@amd.com \
--cc=Greg.Stoner@amd.com \
--cc=John.Bridgman@amd.com \
--cc=Laurent.Morichetti@amd.com \
--cc=Michael.Mantor@amd.com \
--cc=Oded.Gabbay@amd.com \
--cc=Paul.Blinzer@amd.com \
--cc=SCheung@nvidia.com \
--cc=aarcange@redhat.com \
--cc=airlied@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=arvindg@nvidia.com \
--cc=ben.sander@amd.com \
--cc=blc@redhat.com \
--cc=cabuschardt@nvidia.com \
--cc=dpoole@nvidia.com \
--cc=haggaie@mellanox.com \
--cc=hpa@zytor.com \
--cc=jakumar@nvidia.com \
--cc=jdonohue@redhat.com \
--cc=jglisse@redhat.com \
--cc=jhubbard@nvidia.com \
--cc=joro@8bytes.org \
--cc=jweiner@redhat.com \
--cc=ldunning@nvidia.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=liranl@mellanox.com \
--cc=lwoodman@redhat.com \
--cc=mgorman@suse.de \
--cc=mhairgrove@nvidia.com \
--cc=peterz@infradead.org \
--cc=raindel@mellanox.com \
--cc=riel@redhat.com \
--cc=roland@purestorage.com \
--cc=sgutti@nvidia.com \
--cc=torvalds@linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).