From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt0-f198.google.com (mail-qt0-f198.google.com [209.85.216.198]) by kanga.kvack.org (Postfix) with ESMTP id 1109F6B0292 for ; Sat, 3 Jun 2017 05:18:50 -0400 (EDT) Received: by mail-qt0-f198.google.com with SMTP id g53so29306442qta.3 for ; Sat, 03 Jun 2017 02:18:50 -0700 (PDT) Received: from mail-qk0-x22c.google.com (mail-qk0-x22c.google.com. [2607:f8b0:400d:c09::22c]) by mx.google.com with ESMTPS id 16si25705393qtv.302.2017.06.03.02.18.49 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 03 Jun 2017 02:18:49 -0700 (PDT) Received: by mail-qk0-x22c.google.com with SMTP id p66so58392700qkf.3 for ; Sat, 03 Jun 2017 02:18:49 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20170601223808.GC2780@redhat.com> References: <20170522165206.6284-1-jglisse@redhat.com> <20170524175349.GB24024@redhat.com> <20170601223808.GC2780@redhat.com> From: Balbir Singh Date: Sat, 3 Jun 2017 19:18:48 +1000 Message-ID: Subject: Re: [HMM 00/15] HMM (Heterogeneous Memory Management) v22 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sender: owner-linux-mm@kvack.org List-ID: To: Jerome Glisse Cc: "akpm@linux-foundation.org" , "linux-kernel@vger.kernel.org" , linux-mm , John Hubbard , David Nellans On Fri, Jun 2, 2017 at 8:38 AM, Jerome Glisse wrote: > On Thu, Jun 01, 2017 at 12:04:02PM +1000, Balbir Singh wrote: >> On Thu, May 25, 2017 at 3:53 AM, Jerome Glisse wrot= e: >> > On Wed, May 24, 2017 at 11:55:12AM +1000, Balbir Singh wrote: >> >> On Tue, May 23, 2017 at 2:51 AM, J=C3=A9r=C3=B4me Glisse wrote: >> >> > Patchset is on top of mmotm mmotm-2017-05-18, git branch: >> >> > >> >> > https://cgit.freedesktop.org/~glisse/linux/log/?h=3Dhmm-v22 >> >> > >> >> > Change since v21 is adding back special refcounting in put_page() t= o >> >> > catch when a ZONE_DEVICE page is free (refcount going from 2 to 1 >> >> > unlike regular page where a refcount of 0 means the page is free). >> >> > See patch 8 of this serie for this refcounting. I did not use stati= c >> >> > keys because it kind of scares me to do that for an inline function= . >> >> > If people strongly feel about this i can try to make static key wor= ks >> >> > here. Kirill will most likely want to review this. >> >> > >> >> > >> >> > Everything else is the same. Below is the long description of what = HMM >> >> > is about and why. At the end of this email i describe briefly each = patch >> >> > and suggest reviewers for each of them. >> >> > >> >> > >> >> > Heterogeneous Memory Management (HMM) (description and justificatio= n) >> >> > >> >> >> >> Thanks for the patches! These patches are very helpful. There are a >> >> few additional things we would need on top of this (once HMM the base >> >> is merged) >> >> >> >> 1. Support for other architectures, we'd like to make sure we can get >> >> this working for powerpc for example. As a first step we have >> >> ZONE_DEVICE enablement patches, but I think we need some additional >> >> patches for iomem space searching and memory hotplug, IIRC >> >> 2. HMM-CDM and physical address based migration bits. In a recent RFC >> >> we decided to try and use the HMM CDM route as a route to implementin= g >> >> coherent device memory as a starting point. It would be nice to have >> >> those patches on top of these once these make it to mm - >> >> https://lwn.net/Articles/720380/ >> >> >> > >> > I intend to post the updated HMM CDM patchset early next week. I am >> > tie in couple internal backport but i should be able to resume work >> > on that this week. >> > >> >> Thanks, I am looking at the HMM CDM branch and trying to forward port >> and see what the results look like on top of HMM-v23. Do we have a timel= ine >> for the v23 merge? >> > > So i am moving to new office and it has taken me more time than i thought > to pack stuff. Attach is first step of CDM on top of lastest HMM. I hope > to have more time tomorrow or next week to finish rebasing patches and to > run some test with stolen ram as CDM memory. > No worries, thanks for the update. I forward ported some of the stuff from HMM-CDM myself for testing on top of v23, with some assumptions and names like MEMORY_PRIVATE_COHERENT (a new type) and arch_add_memory for hotplug. I also modified Reza's driver (test) to see how far I can get with HMM-CDM. I look forward to the HMM-CDM patchset that you post. Balbir Singh -- 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: email@kvack.org