|
|
|
|
|
|
|
|
|
|
xen-devel
RE: [Xen-devel] [PATCH 1/5] Add MSI support to XEN
To: |
"Keir Fraser" <keir.fraser@xxxxxxxxxxxxx>, "Tian, Kevin" <kevin.tian@xxxxxxxxx>, "xen-devel" <xen-devel@xxxxxxxxxxxxxxxxxxx> |
Subject: |
RE: [Xen-devel] [PATCH 1/5] Add MSI support to XEN |
From: |
"Shan, Haitao" <haitao.shan@xxxxxxxxx> |
Date: |
Fri, 28 Mar 2008 18:13:09 +0800 |
Cc: |
"Jiang, Yunhong" <yunhong.jiang@xxxxxxxxx>, "Li, Xin B" <xin.b.li@xxxxxxxxx> |
Delivery-date: |
Fri, 28 Mar 2008 03:15:51 -0700 |
Envelope-to: |
www-data@xxxxxxxxxxxxxxxxxx |
In-reply-to: |
<C412725B.1E753%keir.fraser@xxxxxxxxxxxxx> |
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/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe> |
List-unsubscribe: |
<http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe> |
References: |
<D470B4E54465E3469E2ABBC5AFAC390F024D9147@xxxxxxxxxxxxxxxxxxxxxxxxxxxx> <C412725B.1E753%keir.fraser@xxxxxxxxxxxxx> |
Sender: |
xen-devel-bounces@xxxxxxxxxxxxxxxxxxx |
Thread-index: |
AciP14w6vOjg7j6MRbadB0OfiPPBYwAAB/ewADZXTlgAAM4IUAAAnY8YAABghBAAAJlgOQAAWNSw |
Thread-topic: |
[Xen-devel] [PATCH 1/5] Add MSI support to XEN |
OK. I will update the patch and send it out again.
Best Regards
Haitao Shan
Keir Fraser wrote:
> On 28/3/08 09:49, "Tian, Kevin" <kevin.tian@xxxxxxxxx> wrote:
>
>>> Yes, the synchronisation is pretty easy though. We just have to add
>>> a layer of emulation to PV guest accesses to 0xcf8/0xcfc.
>>
>> Yes, a small tricky however is, the owner vcpu may be scheduled
>> out between 0xcf8 and 0xcfc access, when another pcpu is trying
>> to access PCI config space like masking MSI within do_IRQ...
>> Maybe Xen need to emulate 0xcf8/0xcfc pair without return to
>> guest in the middle. :-)
>
> Not at all. You track the guest's 0xcf8 value in the vcpu structure,
> and issue the physical 0xcf8/0xcfc access as a pair, under a
> spinlock, whenever the guest writes 0xcfc.
>
> -- Keir
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
|
|
|
|
|