From: "Michael S. Tsirkin" <mst@redhat.com>
To: Rafael Aquini <aquini@redhat.com>
Cc: Rik van Riel <riel@redhat.com>,
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
Peter Zijlstra <peterz@infradead.org>,
linux-kernel@vger.kernel.org,
virtualization@lists.linux-foundation.org, linux-mm@kvack.org,
Andi Kleen <andi@firstfloor.org>,
Minchan Kim <minchan@kernel.org>,
Andrew Morton <akpm@linux-foundation.org>,
"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Subject: Re: [PATCH v8 1/5] mm: introduce a common interface for balloon pages mobility
Date: Tue, 21 Aug 2012 22:30:31 +0300 [thread overview]
Message-ID: <20120821193031.GC9027@redhat.com> (raw)
In-Reply-To: <20120821192357.GD12294@t510.redhat.com>
On Tue, Aug 21, 2012 at 04:23:58PM -0300, Rafael Aquini wrote:
> On Tue, Aug 21, 2012 at 10:13:30PM +0300, Michael S. Tsirkin wrote:
> > >
> > > I believe rcu_dereference_protected() is what I want/need here, since this code
> > > is always called for pages which we hold locked (PG_locked bit).
> >
> > It would only help if we locked the page while updating the mapping,
> > as far as I can see we don't.
> >
>
> But we can do it. In fact, by doing it (locking the page) we can easily avoid
> the nasty race balloon_isolate_page / leak_balloon, in a much simpler way, IMHO.
Absolutely. Further, we should look hard at whether most RCU uses
in this patchset can be replaced with page lock.
--
MST
next prev parent reply other threads:[~2012-08-21 19:30 UTC|newest]
Thread overview: 51+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <cover.1345519422.git.aquini@redhat.com>
2012-08-21 12:47 ` [PATCH v8 1/5] mm: introduce a common interface for balloon pages mobility Rafael Aquini
2012-08-21 13:52 ` Michael S. Tsirkin
2012-08-21 15:20 ` Peter Zijlstra
[not found] ` <1345562411.23018.111.camel@twins>
2012-08-21 16:24 ` Paul E. McKenney
2012-08-21 17:28 ` Rafael Aquini
[not found] ` <20120821172819.GA12294@t510.redhat.com>
2012-08-21 19:13 ` Michael S. Tsirkin
2012-08-21 19:23 ` Rafael Aquini
[not found] ` <20120821192357.GD12294@t510.redhat.com>
2012-08-21 19:30 ` Michael S. Tsirkin [this message]
2012-08-21 20:45 ` Rafael Aquini
[not found] ` <20120821204556.GF12294@t510.redhat.com>
2012-08-22 0:07 ` Michael S. Tsirkin
[not found] ` <20120822000741.GI9027@redhat.com>
2012-08-22 1:19 ` Rafael Aquini
[not found] ` <20120822011930.GA23753@t510.redhat.com>
2012-08-22 9:33 ` Michael S. Tsirkin
[not found] ` <20120822093317.GC10680@redhat.com>
2012-08-23 2:19 ` Rafael Aquini
[not found] ` <20120823021903.GA23660@x61.redhat.com>
2012-08-23 10:01 ` Michael S. Tsirkin
[not found] ` <20120823100107.GA17409@redhat.com>
2012-08-23 12:13 ` Rafael Aquini
[not found] ` <20120823121338.GA3062@t510.redhat.com>
2012-08-23 12:34 ` Michael S. Tsirkin
[not found] ` <20120823123432.GA25659@redhat.com>
2012-08-23 13:06 ` Rafael Aquini
[not found] ` <20120823130606.GB3746@t510.redhat.com>
2012-08-23 13:53 ` Michael S. Tsirkin
[not found] ` <20120823135328.GB25709@redhat.com>
2012-08-23 15:21 ` Rafael Aquini
[not found] ` <20120823152128.GA8975@t510.redhat.com>
2012-08-23 15:54 ` Michael S. Tsirkin
[not found] ` <20120823155401.GA28876@redhat.com>
2012-08-23 16:03 ` Rik van Riel
[not found] ` <50365443.1070104@redhat.com>
2012-08-23 16:06 ` Rafael Aquini
[not found] ` <20120823160647.GA10777@t510.redhat.com>
2012-08-23 16:10 ` Michael S. Tsirkin
2012-08-23 16:25 ` Michael S. Tsirkin
[not found] ` <20120823162504.GA1522@redhat.com>
2012-08-23 17:28 ` Rafael Aquini
[not found] ` <20120823172844.GC10777@t510.redhat.com>
2012-08-23 17:59 ` Rik van Riel
2012-08-23 23:36 ` Michael S. Tsirkin
[not found] ` <20120823233616.GB2775@redhat.com>
2012-08-24 0:26 ` Rafael Aquini
2012-08-24 0:33 ` Rafael Aquini
[not found] ` <20120824003353.GG10777@t510.redhat.com>
2012-08-24 0:38 ` Rafael Aquini
[not found] ` <20120824003848.GH10777@t510.redhat.com>
2012-08-24 0:49 ` Rafael Aquini
2012-08-24 3:12 ` Rik van Riel
[not found] ` <5036F111.4040607@redhat.com>
2012-08-24 8:03 ` Michael S. Tsirkin
[not found] ` <20120821135223.GA7117@redhat.com>
2012-08-21 14:25 ` Michael S. Tsirkin
2012-08-21 15:16 ` Peter Zijlstra
[not found] ` <1345562166.23018.109.camel@twins>
2012-08-21 15:41 ` Michael S. Tsirkin
[not found] ` <20120821154142.GA8268@redhat.com>
2012-08-21 17:42 ` Rafael Aquini
[not found] ` <20120821174251.GB12294@t510.redhat.com>
2012-08-21 19:28 ` Michael S. Tsirkin
2012-08-21 17:55 ` Rafael Aquini
[not found] ` <20120821175502.GC12294@t510.redhat.com>
2012-08-21 19:16 ` Michael S. Tsirkin
[not found] ` <20120821191612.GA9027@redhat.com>
2012-08-21 19:34 ` Rafael Aquini
2012-08-22 0:06 ` Michael S. Tsirkin
2012-08-21 12:47 ` [PATCH v8 2/5] mm: introduce compaction and migration for ballooned pages Rafael Aquini
2012-08-21 12:47 ` [PATCH v8 3/5] virtio_balloon: introduce migration primitives to balloon pages Rafael Aquini
2012-08-21 12:47 ` [PATCH v8 4/5] mm: introduce putback_movable_pages() Rafael Aquini
2012-08-21 12:47 ` [PATCH v8 5/5] mm: add vm event counters for balloon pages compaction Rafael Aquini
[not found] ` <16a7bbe6c1d4df624679646ef13566798a82798f.1345519422.git.aquini@redhat.com>
2012-08-21 14:42 ` [PATCH v8 4/5] mm: introduce putback_movable_pages() Michael S. Tsirkin
[not found] ` <c5f02c618c99b0da11240c1b504672de6f70a074.1345519422.git.aquini@redhat.com>
2012-08-21 14:40 ` [PATCH v8 3/5] virtio_balloon: introduce migration primitives to balloon pages Michael S. Tsirkin
2012-08-21 14:57 ` Michael S. Tsirkin
[not found] ` <20120821144013.GA7784@redhat.com>
2012-08-21 15:34 ` Peter Zijlstra
2012-08-21 15:37 ` Peter Zijlstra
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=20120821193031.GC9027@redhat.com \
--to=mst@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=andi@firstfloor.org \
--cc=aquini@redhat.com \
--cc=konrad.wilk@oracle.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=minchan@kernel.org \
--cc=paulmck@linux.vnet.ibm.com \
--cc=peterz@infradead.org \
--cc=riel@redhat.com \
--cc=virtualization@lists.linux-foundation.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;
as well as URLs for NNTP newsgroup(s).