|
|
|
|
|
|
|
|
|
|
xen-devel
[Xen-devel] Re: [PATCH] xen: drop anti-dependency on X86_VISWS
To: |
Ian Campbell <Ian.Campbell@xxxxxxxxxxxxx> |
Subject: |
[Xen-devel] Re: [PATCH] xen: drop anti-dependency on X86_VISWS |
From: |
Jeremy Fitzhardinge <jeremy@xxxxxxxx> |
Date: |
Fri, 08 Apr 2011 08:25:50 -0700 |
Cc: |
"randy.dunlap@xxxxxxxxxx" <randy.dunlap@xxxxxxxxxx>, Jeremy Fitzhardinge <Jeremy.Fitzhardinge@xxxxxxxxxx>, "eric.dumazet@xxxxxxxxx" <eric.dumazet@xxxxxxxxx>, "konrad.wilk@xxxxxxxxxx" <konrad.wilk@xxxxxxxxxx>, David Miller <davem@xxxxxxxxxxxxx>, "mirq-linux@xxxxxxxxxxxx" <mirq-linux@xxxxxxxxxxxx>, "mingo@xxxxxxxxxx" <mingo@xxxxxxxxxx>, "hpa@xxxxxxxxx" <hpa@xxxxxxxxx>, "tglx@xxxxxxxxxxxxx" <tglx@xxxxxxxxxxxxx>, "virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx" <virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx>, "pazke@xxxxxxxxx" <pazke@xxxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx> |
Delivery-date: |
Fri, 08 Apr 2011 08:26:27 -0700 |
Envelope-to: |
www-data@xxxxxxxxxxxxxxxxxxx |
In-reply-to: |
<1302244694.31620.44.camel@xxxxxxxxxxxxxxxxxxxxx> |
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: |
<1301828839.2837.143.camel@edumazet-laptop> <20110403.172407.91341067.davem@xxxxxxxxxxxxx> <1301910955.23887.75.camel@xxxxxxxxxxxxxxxxxxxxxx> <20110406.144515.235693855.davem@xxxxxxxxxxxxx> <1302159483.31620.36.camel@xxxxxxxxxxxxxxxxxxxxx> <4D9DFD6A.1060200@xxxxxxxx> <1302244694.31620.44.camel@xxxxxxxxxxxxxxxxxxxxx> |
Sender: |
xen-devel-bounces@xxxxxxxxxxxxxxxxxxx |
User-agent: |
Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.15) Gecko/20110307 Fedora/3.1.9-0.39.b3pre.fc14 Lightning/1.0b3pre Thunderbird/3.1.9 |
On 04/07/2011 11:38 PM, Ian Campbell wrote:
>> Not really. The TSC register is a requirement, but that's going to be
>> present on any CPU which can boot Xen. We don't need any of the
>> kernel's TSC machinery though.
> So why the Kconfig dependency then? In principal a kernel compiled for a
> non-TSC processor (which meets the other requirements for Xen, such as
> PAE support) will run just fine under Xen on a newer piece of hardware.
Not sure where it came from. It was probably never needed, or just
added for some secondary effect we wanted.
> Is there any downside to this patch (is X86_CMPXCHG in the same sort of
> boat?)
Only if we don't use cmpxchg in shared memory with other domains or the
hypervisor. (I don't think it will dynamically switch between real and
emulated cmpxchg depending on availability.)
J
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
|
|
|
|
|