From: Jason Gunthorpe <jgg@ziepe.ca>
To: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
linux-mm <linux-mm@kvack.org>,
Andrew Morton <akpm@linux-foundation.org>,
Vlastimil Babka <vbabka@suse.cz>, Michal Hocko <mhocko@suse.com>,
David Hildenbrand <david@redhat.com>,
Oscar Salvador <osalvador@suse.de>,
Dan Williams <dan.j.williams@intel.com>,
Sasha Levin <sashal@kernel.org>,
Tyler Hicks <tyhicks@linux.microsoft.com>,
Joonsoo Kim <iamjoonsoo.kim@lge.com>,
mike.kravetz@oracle.com, Steven Rostedt <rostedt@goodmis.org>,
Ingo Molnar <mingo@redhat.com>,
Peter Zijlstra <peterz@infradead.org>,
Mel Gorman <mgorman@suse.de>,
Matthew Wilcox <willy@infradead.org>,
David Rientjes <rientjes@google.com>,
John Hubbard <jhubbard@nvidia.com>,
Linux Doc Mailing List <linux-doc@vger.kernel.org>,
Ira Weiny <ira.weiny@intel.com>,
linux-kselftest@vger.kernel.org
Subject: Re: [PATCH v6 08/14] mm/gup: do not migrate zero page
Date: Mon, 25 Jan 2021 10:28:19 -0400 [thread overview]
Message-ID: <20210125142819.GU4605@ziepe.ca> (raw)
In-Reply-To: <CA+CK2bCu-uWWOxS_sPhfgzXTq-cqYFsHK_QFo7F+rStKpJJDRA@mail.gmail.com>
On Wed, Jan 20, 2021 at 09:26:41AM -0500, Pavel Tatashin wrote:
> I thought about this, and it would code a little cleaner. But, the
> reason I did not is because zero_page is perfectly pinnable, it is not
> pinnable only when it is in a movable zone (and it should not be in a
> movable zones for other reasons as well), but that is another bug that
> needs to be resolved, and once that bug is resolved this condition can
> be removed from gup migration.
My point is you've defined the zero page to be pinnable no matter what
zone it is in, so is_pinnable(zero_page) == true
Jason
next prev parent reply other threads:[~2021-01-25 14:28 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-20 1:43 [PATCH v6 00/14] prohibit pinning pages in ZONE_MOVABLE Pavel Tatashin
2021-01-20 1:43 ` [PATCH v6 01/14] mm/gup: don't pin migrated cma pages in movable zone Pavel Tatashin
2021-01-20 1:43 ` [PATCH v6 02/14] mm/gup: check every subpage of a compound page during isolation Pavel Tatashin
2021-01-20 1:43 ` [PATCH v6 03/14] mm/gup: return an error on migration failure Pavel Tatashin
2021-01-20 1:43 ` [PATCH v6 04/14] mm/gup: check for isolation errors Pavel Tatashin
2021-01-20 1:43 ` [PATCH v6 05/14] mm cma: rename PF_MEMALLOC_NOCMA to PF_MEMALLOC_PIN Pavel Tatashin
2021-01-20 1:43 ` [PATCH v6 06/14] mm: apply per-task gfp constraints in fast path Pavel Tatashin
2021-01-20 1:43 ` [PATCH v6 07/14] mm: honor PF_MEMALLOC_PIN for all movable pages Pavel Tatashin
2021-01-20 1:43 ` [PATCH v6 08/14] mm/gup: do not migrate zero page Pavel Tatashin
2021-01-20 13:14 ` Jason Gunthorpe
2021-01-20 14:26 ` Pavel Tatashin
2021-01-25 14:28 ` Jason Gunthorpe [this message]
2021-01-25 15:38 ` Pavel Tatashin
2021-01-20 1:43 ` [PATCH v6 09/14] mm/gup: migrate pinned pages out of movable zone Pavel Tatashin
2021-01-20 17:50 ` kernel test robot
2021-01-20 21:31 ` Pavel Tatashin
2021-01-20 1:43 ` [PATCH v6 10/14] memory-hotplug.rst: add a note about ZONE_MOVABLE and page pinning Pavel Tatashin
2021-01-20 13:22 ` Jason Gunthorpe
2021-01-20 14:28 ` Pavel Tatashin
2021-01-20 1:43 ` [PATCH v6 11/14] mm/gup: change index type to long as it counts pages Pavel Tatashin
2021-01-20 1:43 ` [PATCH v6 12/14] mm/gup: longterm pin migration cleaup Pavel Tatashin
2021-01-20 13:19 ` Jason Gunthorpe
2021-01-20 14:17 ` Pavel Tatashin
2021-01-20 1:43 ` [PATCH v6 13/14] selftests/vm: test flag is broken Pavel Tatashin
2021-01-20 1:43 ` [PATCH v6 14/14] selftests/vm: test faulting in kernel, and verify pinnable pages Pavel Tatashin
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=20210125142819.GU4605@ziepe.ca \
--to=jgg@ziepe.ca \
--cc=akpm@linux-foundation.org \
--cc=dan.j.williams@intel.com \
--cc=david@redhat.com \
--cc=iamjoonsoo.kim@lge.com \
--cc=ira.weiny@intel.com \
--cc=jhubbard@nvidia.com \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-kselftest@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mgorman@suse.de \
--cc=mhocko@suse.com \
--cc=mike.kravetz@oracle.com \
--cc=mingo@redhat.com \
--cc=osalvador@suse.de \
--cc=pasha.tatashin@soleen.com \
--cc=peterz@infradead.org \
--cc=rientjes@google.com \
--cc=rostedt@goodmis.org \
--cc=sashal@kernel.org \
--cc=tyhicks@linux.microsoft.com \
--cc=vbabka@suse.cz \
--cc=willy@infradead.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