 Home |
Products |
Support |
Community |
News |
xen-devel
Re: [Xen-devel] [PATCH] Avoid endless loop for vcpu migration
| To: | Juergen Gross <juergen.gross@xxxxxxxxxxxxxx>, Jan Beulich <JBeulich@xxxxxxxxxx> |
|---|---|
| Subject: | Re: [Xen-devel] [PATCH] Avoid endless loop for vcpu migration |
| From: | Keir Fraser <keir.xen@xxxxxxxxx> |
| Date: | Tue, 15 Mar 2011 08:50:20 +0000 |
| Cc: | xen-devel@xxxxxxxxxxxxxxxxxxx |
| Delivery-date: | Tue, 15 Mar 2011 01:51:11 -0700 |
| Dkim-signature: | v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:user-agent:date:subject:from:to:cc:message-id :thread-topic:thread-index:in-reply-to:mime-version:content-type :content-transfer-encoding; bh=Whm2HzmXmG7kcyBRgAoqXF/sY0u51DAy5g/UCd9dUV4=; b=WKxdco4GkirfUHvcChUOeegOs1916wHtyC8+PytsND54yDth48+6D83cyDUyxkq4IT jJpwfqQ8C2obW2muETsVZETLSd3FEGJjIskZJ2BO2MOwnzTe6c/Nlr8UZVvZf9iJczAB UEdlX8N29JxbkKT2z2p8Owa663kMI7KYnFns0= |
| Domainkey-signature: | a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=user-agent:date:subject:from:to:cc:message-id:thread-topic :thread-index:in-reply-to:mime-version:content-type :content-transfer-encoding; b=iY1BY3SswEX/WTt5e48ggZmP8Vc3YRHtZMLzA3NyeRivGh8t8iWLVz+Hjg0k5/Jawd UVR/VGquFwwYNqFzeYOnE3p1nl+QsKPN/D5w5ZDDPKjW2k2NkoYZCwAQFKGwjfisCjzG dTFaAWl1JNQAZzLA2uuBeg70Ro4CUIbQJ2sUE= |
| Envelope-to: | www-data@xxxxxxxxxxxxxxxxxxx |
| In-reply-to: | <4D7F2750.4010607@xxxxxxxxxxxxxx> |
| 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> |
| Sender: | xen-devel-bounces@xxxxxxxxxxxxxxxxxxx |
| Thread-index: | Acvi7gOPtbpbWOXojEaL9qqYoJ1zyw== |
| Thread-topic: | [Xen-devel] [PATCH] Avoid endless loop for vcpu migration |
| User-agent: | Microsoft-Entourage/12.28.0.101117 |
On 15/03/2011 08:46, "Juergen Gross" <juergen.gross@xxxxxxxxxxxxxx> wrote: >> It's not critical, and not affecting correctness. But with updating >> idle_bias on the first invocation you're (on the right hardware) >> basically guaranteeing the second invocation to return a >> different CPU. That way, your loop will be run minimally three >> times on such systems. I already find it odd to require two >> iterations when previously this was a strait code path. > > This was wrong. It was always required to hold the schedule lock of the > picked cpu as well, otherwise a race with cpu hotplug would be possible. What would that race be? CPU offlining is done in stop_machine context. -- Keir _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxxxxxxxx http://lists.xensource.com/xen-devel |
| Previous by Date: | Re: [Xen-devel] [PATCH] Avoid endless loop for vcpu migration, Juergen Gross |
|---|---|
| Next by Date: | Re: [Xen-devel] [PATCH] Avoid endless loop for vcpu migration, Juergen Gross |
| Previous by Thread: | Re: [Xen-devel] [PATCH] Avoid endless loop for vcpu migration, Juergen Gross |
| Next by Thread: | Re: [Xen-devel] [PATCH] Avoid endless loop for vcpu migration, Juergen Gross |
| Indexes: | [Date] [Thread] [Top] [All Lists] |
