From: David Hildenbrand <david@redhat.com>
To: Peter Xu <peterx@redhat.com>,
linux-kernel@vger.kernel.org, linux-mm@kvack.org
Cc: Andrew Morton <akpm@linux-foundation.org>,
Hugh Dickins <hughd@google.com>,
Andrea Arcangeli <aarcange@redhat.com>,
Mike Rapoport <rppt@linux.vnet.ibm.com>
Subject: Re: [PATCH] mm: Don't fault around userfaultfd-registered regions on reads
Date: Fri, 27 Nov 2020 18:00:44 +0100 [thread overview]
Message-ID: <a240da04-1446-9282-c250-00507b745744@redhat.com> (raw)
In-Reply-To: <20201126222359.8120-1-peterx@redhat.com>
On 26.11.20 23:23, Peter Xu wrote:
> Faulting around for reads are in most cases helpful for the performance so that
> continuous memory accesses may avoid another trip of page fault. However it
> may not always work as expected.
>
> For example, userfaultfd registered regions may not be the best candidate for
> pre-faults around the reads.
Are we getting uffd faults even though no-one actually accessed it? So
in case I would track what some part of my program actually reads, I
would get wrong notifications?
--
Thanks,
David / dhildenb
next prev parent reply other threads:[~2020-11-27 17:00 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-26 22:23 Peter Xu
2020-11-27 8:16 ` Mike Rapoport
2020-11-27 13:31 ` Peter Xu
2020-11-27 12:22 ` Matthew Wilcox
2020-11-27 13:51 ` Peter Xu
2020-11-28 0:33 ` Andrea Arcangeli
2020-11-28 15:29 ` Peter Xu
2020-12-01 19:08 ` Andrea Arcangeli
2020-12-01 21:31 ` Hugh Dickins
2020-12-01 23:42 ` Andrea Arcangeli
2020-11-27 17:00 ` David Hildenbrand [this message]
2020-11-27 18:28 ` Peter Xu
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