From: Michal Hocko <mhocko@kernel.org>
To: Luiz Capitulino <lcapitulino@redhat.com>,
Mike Kravetz <mike.kravetz@oracle.com>
Cc: linux-mm@kvack.org, LKML <linux-kernel@vger.kernel.org>
Subject: gigantic hugepages vs. movable zones
Date: Wed, 26 Jul 2017 12:50:04 +0200 [thread overview]
Message-ID: <20170726105004.GI2981@dhcp22.suse.cz> (raw)
Hi,
I've just noticed that alloc_gigantic_page ignores movability of the
gigantic page and it uses any existing zone. Considering that
hugepage_migration_supported only supports 2MB and pgd level hugepages
then 1GB pages are not migratable and as such allocating them from a
movable zone will break the basic expectation of this zone. Standard
hugetlb allocations try to avoid that by using htlb_alloc_mask and I
believe we should do the same for gigantic pages as well.
I suspect this behavior is not intentional. What do you think about the
following untested patch?
---
next reply other threads:[~2017-07-26 10:50 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-07-26 10:50 Michal Hocko [this message]
2017-07-27 2:22 ` Aneesh Kumar K.V
2017-07-27 7:28 ` Michal Hocko
2017-07-27 8:00 ` Aneesh Kumar K.V
2017-07-27 8:12 ` Michal Hocko
2017-07-27 8:22 ` Michal Hocko
2017-07-27 11:56 ` Vlastimil Babka
2017-07-28 20:48 ` Mike Kravetz
2017-07-31 6:47 ` Michal Hocko
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=20170726105004.GI2981@dhcp22.suse.cz \
--to=mhocko@kernel.org \
--cc=lcapitulino@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mike.kravetz@oracle.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