From: Andrea Arcangeli <aarcange@redhat.com>
To: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Avi Kivity <avi@redhat.com>, KVM list <kvm@vger.kernel.org>
Subject: Re: unit tests and get_user_pages_ptes_fast()
Date: Tue, 5 Oct 2010 16:15:47 +0200 [thread overview]
Message-ID: <20101005141547.GV26357@random.random> (raw)
In-Reply-To: <20101005092217.GA15663@amt.cnet>
On Tue, Oct 05, 2010 at 06:22:17AM -0300, Marcelo Tosatti wrote:
> It'll not be so advantageous for ksm because there should be read-faults
> very rarely on that case.
It'll also make all clean swapcache dirty for no good.
> Will post.
If we've to walk pagetables twice, why don't you do this:
writable=1
get_user_pages_fast(write=write_fault)
if (!write_fault)
writable = __get_user_pages_fast(write=1)
That will solve the debugging knob and it'll solve ksm and it'll be
optimal for read swapins on exclusive clean swapcache too.
next prev parent reply other threads:[~2010-10-05 14:15 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-10-04 9:35 unit tests and get_user_pages_ptes_fast() Avi Kivity
2010-10-04 13:40 ` Andrea Arcangeli
2010-10-04 23:59 ` Marcelo Tosatti
2010-10-05 7:36 ` Avi Kivity
2010-10-05 9:22 ` Marcelo Tosatti
2010-10-05 14:15 ` Andrea Arcangeli [this message]
2010-10-05 14:25 ` Avi Kivity
2010-10-05 14:32 ` Andrea Arcangeli
2010-10-05 14:36 ` Avi Kivity
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=20101005141547.GV26357@random.random \
--to=aarcange@redhat.com \
--cc=avi@redhat.com \
--cc=kvm@vger.kernel.org \
--cc=mtosatti@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