From: Christoph Hellwig <hch@infradead.org>
To: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Christoph Hellwig <hch@infradead.org>,
Mikulas Patocka <mpatocka@redhat.com>,
Jens Axboe <axboe@kernel.dk>, Jooyung Han <jooyung@google.com>,
Alasdair Kergon <agk@redhat.com>,
Mike Snitzer <snitzer@kernel.org>,
Heinz Mauelshagen <heinzm@redhat.com>,
zkabelac@redhat.com, dm-devel@lists.linux.dev,
linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] the dm-loop target
Date: Wed, 12 Mar 2025 07:20:11 -0700 [thread overview]
Message-ID: <Z9GYGyjJcXLvtDfv@infradead.org> (raw)
In-Reply-To: <2pwjcvwkfasiwq5cum63ytgurs6wqzhlh6r25amofjz74ykybi@ru2qpz7ug6eb>
On Wed, Mar 12, 2025 at 09:26:55AM -0400, Kent Overstreet wrote:
> We might be able to provide an API to _request_ a stable mapping to a
> file - with proper synchronization, of course.
We already have that with the pNFS layouts.
> I don't recall anyone ever trying that, it'd replace all the weird
> IF_SWAPFILE() hacks and be a safe way to do these kinds of performance
> optimizations.
IS_SWAPFILE isn't going way, as can't allow other writers to it.
Also asides from the that the layouts are fairly complex.
The right way ahead for swap is to literally just treat it as a slightly
special case of direct I/o that is allowed to IS_SWAPFILE files. We
can safely do writeback to file backed folios under memory pressure,
so we can also go through the normal file system path.
next prev parent reply other threads:[~2025-03-12 14:20 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <7d6ae2c9-df8e-50d0-7ad6-b787cb3cfab4@redhat.com>
2025-03-03 13:59 ` [PATCH] the dm-loop target Christoph Hellwig
[not found] ` <CAM23VxprhJgOPfhxQf6QNWzHd6+-ZwbjSo-oMHCD2WDQiKntMg@mail.gmail.com>
2025-03-03 15:13 ` Christoph Hellwig
2025-03-03 15:22 ` Matthew Wilcox
2025-03-03 15:31 ` Christoph Hellwig
[not found] ` <CAM23VxprSduDDK8qvLVkUt9WWmLMPFjhqKB8X4e6gw7Wv-6R2w@mail.gmail.com>
2025-03-03 17:24 ` Christoph Hellwig
[not found] ` <CAM23Vxoxyrf9nwJd1Xe8uncAPiyK8yaNZNsugwX8p=qo1n6yVg@mail.gmail.com>
2025-03-04 13:52 ` Christoph Hellwig
2025-03-03 16:16 ` Mikulas Patocka
2025-03-03 17:24 ` Christoph Hellwig
2025-03-03 21:03 ` Mikulas Patocka
2025-03-04 2:13 ` Dave Chinner
2025-03-04 11:18 ` Mikulas Patocka
2025-03-04 13:50 ` Christoph Hellwig
2025-03-05 0:01 ` Dave Chinner
2025-03-07 15:21 ` Mikulas Patocka
2025-03-08 3:49 ` Darrick J. Wong
2025-03-08 20:45 ` Mikulas Patocka
2025-03-09 0:05 ` Ming Lei
2025-03-10 11:18 ` Mikulas Patocka
2025-03-11 1:27 ` Dave Chinner
2025-03-11 10:43 ` Ming Lei
2025-03-12 2:34 ` Dave Chinner
2025-03-12 6:24 ` Christoph Hellwig
2025-03-12 8:26 ` Ming Lei
2025-03-13 1:36 ` Ming Lei
2025-03-13 16:36 ` Mikulas Patocka
2025-03-18 4:27 ` Dave Chinner
2025-03-18 7:57 ` Christoph Hellwig
2025-03-18 9:34 ` Ming Lei
2025-03-20 7:08 ` Christoph Hellwig
2025-03-20 7:41 ` Ming Lei
2025-03-20 14:22 ` Christoph Hellwig
2025-03-20 14:36 ` Ming Lei
2025-03-25 10:15 ` Dave Chinner
2025-03-25 12:23 ` Ming Lei
2025-03-09 0:16 ` Ming Lei
2025-03-10 11:20 ` Mikulas Patocka
2025-03-04 13:49 ` Christoph Hellwig
[not found] ` <CAM23Vxr=fKy-0L1R5P-5h6A95acKT_d=CC1E+TAzAs8v6q9gHw@mail.gmail.com>
2025-03-04 16:04 ` Christoph Hellwig
[not found] ` <CAM23VxqJX46DCpCiH5qxPpDLtMVg87Ba8sx55aQ4hvt-XaHzuQ@mail.gmail.com>
2025-03-04 17:17 ` Christoph Hellwig
2025-03-12 13:26 ` Kent Overstreet
2025-03-12 14:20 ` Christoph Hellwig [this message]
2025-03-12 16:09 ` Kent Overstreet
2025-03-13 12:44 ` Christoph Hellwig
2025-03-13 16:21 ` Mikulas Patocka
2025-03-13 16:33 ` Kent Overstreet
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