From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: xl vcpu-set does not work properly. Date: Mon, 9 Dec 2013 16:52:19 -0500 Message-ID: <20131209215219.GC3000@phenom.dumpdata.com> References: <20131204195723.GB3833@pegasus.dumpdata.com> <20131205122656.GP10855@perard.uk.xensource.com> <20131209171028.GT10855@perard.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta4.messagelabs.com ([85.158.143.247]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1VqOPt-0003FH-QG for xen-devel@lists.xenproject.org; Tue, 10 Dec 2013 14:36:06 +0000 Content-Disposition: inline In-Reply-To: <20131209171028.GT10855@perard.uk.xensource.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Anthony PERARD Cc: xen-devel@lists.xenproject.org, stefano.stabellini@eu.citrix.com List-Id: xen-devel@lists.xenproject.org On Mon, Dec 09, 2013 at 05:10:28PM +0000, Anthony PERARD wrote: > On Thu, Dec 05, 2013 at 12:27:21PM +0000, Anthony PERARD wrote: > > On Wed, Dec 04, 2013 at 02:57:24PM -0500, Konrad Rzeszutek Wilk wrote: > > > When I try this with the "SeaBIOS" QEMU it does not hotplug > > > all of the CPUs and it complains about the existing ones: > > > > > > [...] > > > > > > -bash-4.1# xl vcpu-list > > > Name ID VCPU CPU State Time(s) CPU > > > Affinity > > > Domain-0 0 0 0 -b- 87.4 any > > > cpu > > > Domain-0 0 1 3 -b- 14.6 any > > > cpu > > > Domain-0 0 2 2 -b- 11.1 any > > > cpu > > > Domain-0 0 3 1 r-- 13.7 any > > > cpu > > > latest 7 0 2 -b- 11.7 any > > > cpu > > > latest 7 1 1 -b- 1.7 any > > > cpu > > > latest 7 2 3 -b- 0.0 any > > > cpu > > > > > > And sure enough - in the guest it only added one CPU: > > > > > > [ 85.720139] CPU2 has been hot-added > > > [ 85.726409] installing Xen timer for CPU 2 > > > [ 85.735674] smpboot: Booting Node 0 Processor 2 APIC 0x4 > > > [ 85.755080] cpu 2 spinlock event irq 86 > > > [ 85.763671] microcode: CPU2 sig=0x206a7, pf=0x2, revision=0x28 > > > [ 85.770669] Will online and init hotplugged CPU: 2 > > > > > > Perhaps the SeaBIOS/new qemu needs variants of: > > > > > > f62079c piix4acpi, xen, hotplug: Fix race with ACPI AML code and hotplug. > > > e28e062 piix4acpi, xen: Clarify that the qemu_set_irq calls just do an IRQ pulse. > > > 2133c38 piix4acpi, xen, vcpu hotplug: Split the notification from the changes > > > > Yes, we should fix that in QEMU. > > > > Thanks for reporting, I will work on it. > > Instead of porting those patch, I think we can fix the issue by a small > change in the ACPI table. I tried to reproduce the issue with KVM, but I > could not, so I tried to compare the ACPI table and there is one detail > that could be interesting, they use Edge-Triggered even, where we have > Level-Triggered even. After a quick test, it looks like it works (to use > Edge-Triggered even). Did you do it with a huge amount of VCPUs? Say you boot with 2 and want to hotplug 32 of them? The reason I am asking is b/c the git commits I mentioned - that is what they were fixing (And also made it work for smaller amount of VCPUs). > > -- > Anthony PERARD