From: Michal Hocko <mhocko@kernel.org>
To: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Alexandru Moise <00moses.alexander00@gmail.com>,
Andrew Morton <akpm@linux-foundation.org>,
Andi Kleen <ak@linux.intel.com>, Andrey Vagin <avagin@openvz.org>,
"Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>,
Anshuman Khandual <khandual@linux.vnet.ibm.com>,
Anton Vorontsov <anton.vorontsov@linaro.org>,
"Artem S. Tashkinov" <t.artem@lycos.com>,
Balbir Singh <bsingharora@gmail.com>,
Chris Salls <salls@cs.ucsb.edu>,
Christopher Lameter <cl@linux.com>,
"Darrick J. Wong" <darrick.wong@oracle.com>,
Dave Chinner <david@fromorbit.com>,
David Rientjes <rientjes@google.com>,
Gerald Schaefer <gerald.schaefer@de.ibm.com>,
Glauber Costa <glommer@openvz.org>,
Henrique de Moraes Holschuh <hmh@hmh.eng.br>,
Ingo Molnar <mingo@kernel.org>, Jan Kara <jack@suse.cz>,
Johannes Weiner <hannes@cmpxchg.org>,
Joonsoo Kim <iamjoonsoo.kim@lge.com>,
Konstantin Khlebnikov <khlebnikov@yandex-team.ru>,
Laurent Dufour <ldufour@linux.vnet.ibm.com>,
Maxim Patlasov <MPatlasov@parallels.com>,
Mel Gorman <mgorman@techsingularity.net>,
Mike Kravetz <mike.kravetz@oracle.com>,
Minchan Kim <minchan@kernel.org>,
Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>,
Punit Agrawal <punit.agrawal@arm.com>,
Rik van Riel <riel@redhat.com>,
Shiraz Hashim <shashim@codeaurora.org>,
Tan Xiaojun <tanxiaojun@huawei.com>,
Theodore Ts'o <tytso@mit.edu>,
Vinayak Menon <vinmenon@codeaurora.org>,
Vladimir Davydov <vdavydov.dev@gmail.com>,
Vlastimil Babka <vbabka@suse.cz>,
Wu Fengguang <fengguang.wu@intel.com>,
Yisheng Xie <xieyisheng1@huawei.com>,
zhong jiang <zhongjiang@huawei.com>,
linux-mm@kvack.org
Subject: Re: stalled MM patches
Date: Fri, 1 Dec 2017 11:17:34 +0100 [thread overview]
Message-ID: <20171201101734.65tubivkejlduq34@dhcp22.suse.cz> (raw)
In-Reply-To: <20171201101147.t62ouec3ebnv7lz5@node.shutemov.name>
On Fri 01-12-17 13:11:47, Kirill A. Shutemov wrote:
> On Fri, Dec 01, 2017 at 09:45:10AM +0100, Michal Hocko wrote:
> > On Fri 01-12-17 09:31:55, Alexandru Moise wrote:
> > [...]
> > > > Subject: mm/madvise: enable soft offline of HugeTLB pages at PUD level
> > > >
> > > > Hoping for Kirill review. I wanted additional code comments (I
> > > > think). mhocko nacked it.
> > >
> > > TBH I'd rather give up this one if mhocko feels that there's no point to it.
> > > Rather drop it than risk adding crap in the kernel :).
> > >
> > > It is a bit weird though that currently we have the behavior that on some PPC platforms
> > > you can migrate 1G hugepages but on x86_64 you cannot.
> >
> > I _think_ we can apply this patch in the end. But there is more work to
> > be done before we can do that. PPC is probably broken in that regard as
> > well, we just haven't noticed before this got merged. I find the
> > hwpoison based reasons for merging disputable at best but this is not
> > serious enough to call for a revert. I am currently working on patches
> > to make giga pages migratable for real and then we can apply your patch
> > on top.
>
> One way we can approach it is to make architecture code to provide
> hugepage_migration_supported() with fallback to "return false;" in generic
> code. It will give us more control on what can be migrated.
>
> And we can kill CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION.
>
> Then we can include new page sizes into migration one-by-one with proper
> testing.
I do not think this is the biggest problem here. The page migration code
is basically generic for hugetlb pages. I seriously suspect anybody has
tested PGD pages migration on PPC. This is all hwpoison driven thing.
So, really, we should make giga pages migration work better first and
then play with hugepage_migration_supported. Arch specific treatment
might be needed but that is not the biggest problem we have.
--
Michal Hocko
SUSE Labs
--
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:[~2017-12-01 10:17 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-11-30 22:14 Andrew Morton
2017-12-01 8:31 ` Alexandru Moise
2017-12-01 8:45 ` Michal Hocko
2017-12-01 10:11 ` Kirill A. Shutemov
2017-12-01 10:17 ` Michal Hocko [this message]
2017-12-01 9:58 ` Yisheng Xie
2017-12-01 12:35 ` Jan Kara
2017-12-01 18:30 ` Darrick J. Wong
2017-12-04 12:23 ` Jan Kara
2017-12-04 15:24 ` Vinayak Menon
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=20171201101734.65tubivkejlduq34@dhcp22.suse.cz \
--to=mhocko@kernel.org \
--cc=00moses.alexander00@gmail.com \
--cc=MPatlasov@parallels.com \
--cc=ak@linux.intel.com \
--cc=akpm@linux-foundation.org \
--cc=aneesh.kumar@linux.vnet.ibm.com \
--cc=anton.vorontsov@linaro.org \
--cc=avagin@openvz.org \
--cc=bsingharora@gmail.com \
--cc=cl@linux.com \
--cc=darrick.wong@oracle.com \
--cc=david@fromorbit.com \
--cc=fengguang.wu@intel.com \
--cc=gerald.schaefer@de.ibm.com \
--cc=glommer@openvz.org \
--cc=hannes@cmpxchg.org \
--cc=hmh@hmh.eng.br \
--cc=iamjoonsoo.kim@lge.com \
--cc=jack@suse.cz \
--cc=khandual@linux.vnet.ibm.com \
--cc=khlebnikov@yandex-team.ru \
--cc=kirill@shutemov.name \
--cc=ldufour@linux.vnet.ibm.com \
--cc=linux-mm@kvack.org \
--cc=mgorman@techsingularity.net \
--cc=mike.kravetz@oracle.com \
--cc=minchan@kernel.org \
--cc=mingo@kernel.org \
--cc=n-horiguchi@ah.jp.nec.com \
--cc=punit.agrawal@arm.com \
--cc=riel@redhat.com \
--cc=rientjes@google.com \
--cc=salls@cs.ucsb.edu \
--cc=shashim@codeaurora.org \
--cc=t.artem@lycos.com \
--cc=tanxiaojun@huawei.com \
--cc=tytso@mit.edu \
--cc=vbabka@suse.cz \
--cc=vdavydov.dev@gmail.com \
--cc=vinmenon@codeaurora.org \
--cc=xieyisheng1@huawei.com \
--cc=zhongjiang@huawei.com \
/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