From: Mike Rapoport <rppt@kernel.org>
To: David Carlier <devnexen@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Peter Xu <peterx@redhat.com>,
linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] mm/userfaultfd: fix wrong likely() hint on mmap_changing check in move_pages()
Date: Tue, 31 Mar 2026 14:42:54 +0300 [thread overview]
Message-ID: <acuzPjzx9byIJ2tG@kernel.org> (raw)
In-Reply-To: <20260328170101.184163-2-devnexen@gmail.com>
On Sat, Mar 28, 2026 at 05:01:01PM +0000, David Carlier wrote:
> The mmap_changing check in move_pages() uses likely() but the condition
> being true (concurrent mapping changes during UFFDIO_MOVE) is the
> exceptional case, not the common one. All other mmap_changing checks in
> the same file correctly use no branch hint or use unlikely().
>
> Replace likely() with unlikely() to match the expected branch behavior.
>
> Signed-off-by: David Carlier <devnexen@gmail.com>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
> ---
> mm/userfaultfd.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
--
Sincerely yours,
Mike.
next prev parent reply other threads:[~2026-03-31 11:43 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-03-28 17:01 [PATCH 1/2] mm/userfaultfd: fix stale ops and VMA type mismatch after copy retry David Carlier
2026-03-28 17:01 ` [PATCH 2/2] mm/userfaultfd: fix wrong likely() hint on mmap_changing check in move_pages() David Carlier
2026-03-30 19:39 ` Peter Xu
2026-03-31 11:42 ` Mike Rapoport [this message]
2026-03-30 19:38 ` [PATCH 1/2] mm/userfaultfd: fix stale ops and VMA type mismatch after copy retry Peter Xu
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=acuzPjzx9byIJ2tG@kernel.org \
--to=rppt@kernel.org \
--cc=akpm@linux-foundation.org \
--cc=devnexen@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=peterx@redhat.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