From: Andrew Morton <akpm@linux-foundation.org>
To: Evan Green <evgreen@chromium.org>
Cc: David Hildenbrand <david@redhat.com>, Pavel Machek <pavel@ucw.cz>,
Alex Shi <alexs@kernel.org>, Alistair Popple <apopple@nvidia.com>,
Jens Axboe <axboe@kernel.dk>,
Johannes Weiner <hannes@cmpxchg.org>,
Joonsoo Kim <iamjoonsoo.kim@lge.com>,
"Matthew Wilcox (Oracle)" <willy@infradead.org>,
Miaohe Lin <linmiaohe@huawei.com>, Michal Hocko <mhocko@suse.com>,
Minchan Kim <minchan@kernel.org>,
Vlastimil Babka <vbabka@suse.cz>,
linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [PATCH v2] mm: Enable suspend-only swap spaces
Date: Fri, 9 Jul 2021 15:20:24 -0700 [thread overview]
Message-ID: <20210709152024.36f650dfec4c66ef3a60a845@linux-foundation.org> (raw)
In-Reply-To: <20210709105012.v2.1.I09866d90c6de14f21223a03e9e6a31f8a02ecbaf@changeid>
On Fri, 9 Jul 2021 10:50:48 -0700 Evan Green <evgreen@chromium.org> wrote:
> Currently it's not possible to enable hibernation without also enabling
> generic swap for a given swap area. These two use cases are not the
> same. For example there may be users who want to enable hibernation,
> but whose drives don't have the write endurance for generic swap
> activities.
>
> Add a new SWAP_FLAG_NOSWAP that adds a swap region but refuses to allow
> generic swapping to it. This region can still be wired up for use in
> suspend-to-disk activities, but will never have regular pages swapped to
> it.
>
> Swap regions with SWAP_FLAG_NOSWAP set will not appear in /proc/meminfo
> under SwapTotal and SwapFree, since they are not usable as general swap.
>
This patch doesn't appear to set SWAP_FLAG_NOSWAP anywhere. Perhaps
there's another patch somewhere which changes the hibernation code? If
so, can we please have both patches in a series?
Once we have a description of how this thing gets set, please let's
discuss what happens if someone tries to enable generic swap onto that
device after hibernation has set SWAP_FLAG_NOSWAP (I'm basically
guessing now). Will it work? Is there a backward-compatibility issue
here?
next prev parent reply other threads:[~2021-07-09 22:20 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-09 17:50 Evan Green
2021-07-09 22:20 ` Andrew Morton [this message]
2021-07-09 23:23 ` Evan Green
2021-07-09 23:33 ` Andrew Morton
2021-07-12 21:36 ` Evan Green
2021-07-12 7:03 ` Michal Hocko
2021-07-12 7:41 ` David Hildenbrand
2021-07-14 5:43 ` Michal Hocko
2021-07-14 7:51 ` David Hildenbrand
2021-07-14 8:00 ` Michal Hocko
2021-07-27 12:04 ` Pavel Machek
2021-07-27 12:19 ` David Hildenbrand
2021-07-27 12:01 ` Pavel Machek
2021-07-12 21:32 ` Evan Green
2021-07-14 5:41 ` Michal Hocko
2021-07-14 22:39 ` Evan Green
2021-07-27 12:10 ` Pavel Machek
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=20210709152024.36f650dfec4c66ef3a60a845@linux-foundation.org \
--to=akpm@linux-foundation.org \
--cc=alexs@kernel.org \
--cc=apopple@nvidia.com \
--cc=axboe@kernel.dk \
--cc=david@redhat.com \
--cc=evgreen@chromium.org \
--cc=hannes@cmpxchg.org \
--cc=iamjoonsoo.kim@lge.com \
--cc=linmiaohe@huawei.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mhocko@suse.com \
--cc=minchan@kernel.org \
--cc=pavel@ucw.cz \
--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