Re: [Xen-devel] xen,arm: enable cpu_hotplug

2015-10-16 Thread Stefano Stabellini
On Thu, 15 Oct 2015, Ian Campbell wrote: > On Thu, 2015-10-15 at 00:23 +0100, Julien Grall wrote: > > My second point is related to how Xen is handling interrupt with vCPU. > > When PSCI off is called, we will set the _VFP_down flag. This flag is > > used in vgic_vcpu_inject_irq and when it's set

Re: [Xen-devel] xen,arm: enable cpu_hotplug

2015-10-16 Thread Stefano Stabellini
On Thu, 15 Oct 2015, Julien Grall wrote: > On 14/10/2015 18:49, Stefano Stabellini wrote: > > Hi all, > > Hi Stefano, > > > this small patch series enable cpu_hotplug in ARM and ARM64 guests, > > using the PV path to plug and unplug the cpus and psci to enable/disable > > them. > > That's a cool

Re: [Xen-devel] xen,arm: enable cpu_hotplug

2015-10-16 Thread Julien Grall
On 16/10/15 16:41, Stefano Stabellini wrote: > It is possible to shut down cpu1 (psci->cpu_off, which pauses the vcpu) > but it is not possible to remove cpu1 without removing cpu2 first. > > If the user configures the target to be cpu 2-4, then shuts down cpu2, it > won't receive any interrupts a

Re: [Xen-devel] xen,arm: enable cpu_hotplug

2015-10-16 Thread Stefano Stabellini
On Thu, 15 Oct 2015, Julien Grall wrote: > Hi Ian, > > On 15/10/15 09:39, Ian Campbell wrote: > > On Thu, 2015-10-15 at 00:23 +0100, Julien Grall wrote: > >> My second point is related to how Xen is handling interrupt with vCPU. > >> When PSCI off is called, we will set the _VFP_down flag. This fla

Re: [Xen-devel] xen,arm: enable cpu_hotplug

2015-10-15 Thread Julien Grall
On 15/10/15 10:57, Julien Grall wrote: > Hi Ian, > > On 15/10/15 09:39, Ian Campbell wrote: >> On Thu, 2015-10-15 at 00:23 +0100, Julien Grall wrote: >>> My second point is related to how Xen is handling interrupt with vCPU. >>> When PSCI off is called, we will set the _VFP_down flag. This flag i

Re: [Xen-devel] xen,arm: enable cpu_hotplug

2015-10-15 Thread Julien Grall
Hi Ian, On 15/10/15 09:39, Ian Campbell wrote: > On Thu, 2015-10-15 at 00:23 +0100, Julien Grall wrote: >> My second point is related to how Xen is handling interrupt with vCPU. >> When PSCI off is called, we will set the _VFP_down flag. This flag is >> used in vgic_vcpu_inject_irq and when it's

Re: [Xen-devel] xen,arm: enable cpu_hotplug

2015-10-15 Thread Ian Campbell
On Thu, 2015-10-15 at 00:23 +0100, Julien Grall wrote: > My second point is related to how Xen is handling interrupt with vCPU. > When PSCI off is called, we will set the _VFP_down flag. This flag is > used in vgic_vcpu_inject_irq and when it's set the interrupt will be > ignored and stay active

Re: [Xen-devel] xen,arm: enable cpu_hotplug

2015-10-14 Thread Julien Grall
On 14/10/2015 18:49, Stefano Stabellini wrote: Hi all, Hi Stefano, this small patch series enable cpu_hotplug in ARM and ARM64 guests, using the PV path to plug and unplug the cpus and psci to enable/disable them. That's a cool things to have on ARM! I've got few questions related to CPU h

[Xen-devel] xen,arm: enable cpu_hotplug

2015-10-14 Thread Stefano Stabellini
Hi all, this small patch series enable cpu_hotplug in ARM and ARM64 guests, using the PV path to plug and unplug the cpus and psci to enable/disable them. Stefano Stabellini (3): xen/arm: Enable cpu_hotplug.c xen, cpu_hotplug: call device_offline instead of cpu_down xen/arm: do