|
|
|
|
|
|
|
|
|
|
xen-devel
[Xen-devel] Re: One (possible) x86 get_user_pages bug
To: |
Jeremy Fitzhardinge <jeremy@xxxxxxxx> |
Subject: |
[Xen-devel] Re: One (possible) x86 get_user_pages bug |
From: |
Avi Kivity <avi@xxxxxxxxxx> |
Date: |
Sun, 30 Jan 2011 15:01:45 +0200 |
Cc: |
Kaushik Barde <kbarde@xxxxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>, Kenneth Lee <liguozhu@xxxxxxxxxx>, Nick Piggin <npiggin@xxxxxxxxx>, Marcelo Tosatti <mtosatti@xxxxxxxxxx>, linux-kernel@xxxxxxxxxxxxxxx, Jan Beulich <JBeulich@xxxxxxxxxx>, wangzhenguo@xxxxxxxxxx, Xiaowei Yang <xiaowei.yang@xxxxxxxxxx>, linqaingmin <linqiangmin@xxxxxxxxxx>, fanhenglong@xxxxxxxxxx, Wu Fengguang <fengguang.wu@xxxxxxxxx>, Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> |
Delivery-date: |
Sun, 30 Jan 2011 05:03:04 -0800 |
Envelope-to: |
www-data@xxxxxxxxxxxxxxxxxxx |
In-reply-to: |
<4D41B90D.5000305@xxxxxxxx> |
List-help: |
<mailto:xen-devel-request@lists.xensource.com?subject=help> |
List-id: |
Xen developer discussion <xen-devel.lists.xensource.com> |
List-post: |
<mailto:xen-devel@lists.xensource.com> |
List-subscribe: |
<http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe> |
List-unsubscribe: |
<http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe> |
References: |
<4D416D9A.9010603@xxxxxxxxxx> <4D419416020000780002ECB7@xxxxxxxxxxxxxxxxxx> <4D41B90D.5000305@xxxxxxxx> |
Sender: |
xen-devel-bounces@xxxxxxxxxxxxxxxxxxx |
User-agent: |
Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.13) Gecko/20101209 Fedora/3.1.7-0.35.b3pre.fc14 Lightning/1.0b3pre Thunderbird/3.1.7 |
On 01/27/2011 08:27 PM, Jeremy Fitzhardinge wrote:
And even just considering virtualization, having non-IPI-based tlb
shootdown is a measurable performance win, since a hypervisor can
optimise away a cross-VCPU shootdown if it knows no physical TLB
contains the target VCPU's entries. I can imagine the KVM folks could
get some benefit from that as well.
It's nice to avoid the IPI (and waking up a cpu if it happens to be
asleep) but I think the risk of deviating too much from the baremetal
arch is too large, as demonstrated by this bug.
(well, async page faults is a counterexample, I wonder if/when it will
bite us)
--
error compiling committee.c: too many arguments to function
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
|
|
|
|
|