WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

Re: [Xen-devel] [PATCH] Add cpu hotplug support for 2.6.32 branch

To: "Jiang, Yunhong" <yunhong.jiang@xxxxxxxxx>
Subject: Re: [Xen-devel] [PATCH] Add cpu hotplug support for 2.6.32 branch
From: Jeremy Fitzhardinge <jeremy@xxxxxxxx>
Date: Wed, 18 Aug 2010 12:41:06 -0700
Cc: Xen-devel <xen-devel@xxxxxxxxxxxxxxxxxxx>
Delivery-date: Wed, 18 Aug 2010 12:42:04 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <789F9655DD1B8F43B48D77C5D306597328C6827D@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>
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: <789F9655DD1B8F43B48D77C5D306597328C6827D@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.7) Gecko/20100720 Fedora/3.1.1-1.fc13 Lightning/1.0b2pre Thunderbird/3.1.1
 On 08/17/2010 08:04 PM, Jiang, Yunhong wrote:
> Hi, Jeremy, followed patch port pcpu hotplug support to 2.6.32 pvops dom0. I 
> don't know if xen/next-2.6.32 branch is the right base. If it is not, can you 
> please advice me which branch should I base on?

No, that's not really a good base.  Ideally you should base on plain
v2.6.32, but if that doesn't work, base it on whatever topic branch has
your pre-requisite changes.  If that's too complex (too many changes
from multiple branches), then base on xen/next.

The existing xen/dom0/pcpu-hotplug branch should a useful guide.

Alternatively, if you can provide me with a merge of
xen/dom0/pcpu-hotplug into xen/next (ie, with conflict resolution done),
then I could just use that. (Though it looks like certain parts may have
already been merged - I didn't look closely.)

Thanks,
    J

> Thanks
> --jyh
>
> Add cpu hotplug support for 2.6.32 branch
>
> Add physical CPU hotplug support to origin/xen/next-2.6.32 branch.
> Please notice that, even with this change, the acpi_processor->id is 
> still always -1. This is because several workaround in PM side depends
> on acpi_processor->id == -1. As the CPU hotplug logic does not depends
> on acpi_processor->id, I'd still keep it no changes.
>
> But we need change the acpi_processor->id in the future.
>
> Signed-off-by: Jiang, Yunhong <yunhong.jiang@xxxxxxxxx>
>
>
> diff --git a/drivers/acpi/processor_xen.c b/drivers/acpi/processor_xen.c
> index 2f37c9c..305398d 100644
> --- a/drivers/acpi/processor_xen.c
> +++ b/drivers/acpi/processor_xen.c
> @@ -39,6 +39,7 @@
>  #include <acpi/acpi_drivers.h>
>  #include <acpi/processor.h>
>  #include <xen/acpi.h>
> +#include <xen/pcpu.h>
>  
>  #define PREFIX "ACPI: "
>  
> @@ -82,6 +83,42 @@ struct acpi_driver xen_acpi_processor_driver = {
>               },
>  };
>  
> +static int is_processor_present(acpi_handle handle)
> +{
> +     acpi_status status;
> +     unsigned long long sta = 0;
> +
> +
> +     status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
> +
> +     if (ACPI_SUCCESS(status) && (sta & ACPI_STA_DEVICE_PRESENT))
> +             return 1;
> +
> +     /*
> +      * _STA is mandatory for a processor that supports hot plug
> +      */
> +     if (status == AE_NOT_FOUND)
> +             ACPI_DEBUG_PRINT((ACPI_DB_INFO,
> +                             "Processor does not support hot plug\n"));
> +     else
> +             ACPI_EXCEPTION((AE_INFO, status,
> +                             "Processor Device is not present"));
> +     return 0;
> +}
> +
> +static acpi_status
> +xen_acpi_processor_hotadd_init(struct acpi_processor *pr, int *p_cpu)
> +{
> +     if (!is_processor_present(pr->handle))
> +             return AE_ERROR;
> +
> +     if (processor_cntl_xen_notify(pr,
> +                             PROCESSOR_HOTPLUG, HOTPLUG_TYPE_ADD))
> +             return AE_ERROR;
> +
> +     return AE_OK;
> +}
> +
>  static int xen_acpi_processor_get_info(struct acpi_device *device)
>  {
>       acpi_status status = 0;
> @@ -164,14 +201,12 @@ static int xen_acpi_processor_get_info(struct 
> acpi_device *device)
>        *  They should be ignored _iff they are physically not present.
>        *
>        */
> -#if 0
> -     if (pr->id == -1) {
> +     if (xen_pcpu_index(pr->acpi_id, 1) == -1) {
>               if (ACPI_FAILURE
> -                 (acpi_processor_hotadd_init(pr->handle, &pr->id))) {
> +                 (xen_acpi_processor_hotadd_init(pr, &pr->id))) {
>                       return -ENODEV;
>               }
>       }
> -#endif
>  
>       /*
>        * On some boxes several processors use the same processor bus id.
> diff --git a/drivers/xen/pcpu.c b/drivers/xen/pcpu.c
> index 6450c17..6d1a770 100644
> --- a/drivers/xen/pcpu.c
> +++ b/drivers/xen/pcpu.c
> @@ -313,6 +313,38 @@ static struct pcpu *_sync_pcpu(int cpu_num, int *max_id, 
> int *result)
>       return pcpu;
>  }
>  
> +int xen_pcpu_index(uint32_t id, int is_acpiid)
> +{
> +     int cpu_num = 0, max_id = 0, ret;
> +     xen_platform_op_t op = {
> +             .cmd            = XENPF_get_cpuinfo,
> +             .interface_version  = XENPF_INTERFACE_VERSION,
> +     };
> +     struct xenpf_pcpuinfo *info = &op.u.pcpu_info;
> +
> +     info->xen_cpuid = 0;
> +     ret = HYPERVISOR_dom0_op(&op);
> +     if (ret)
> +             return -1;
> +     max_id = op.u.pcpu_info.max_present;
> +
> +     while ((cpu_num <= max_id)) {
> +             info->xen_cpuid = cpu_num;
> +             ret = HYPERVISOR_dom0_op(&op);
> +             if (ret)
> +                     continue;
> +
> +             if (op.u.pcpu_info.max_present > max_id)
> +                     max_id = op.u.pcpu_info.max_present;
> +             if (id == (is_acpiid ? info->acpi_id : info->apic_id))
> +                     return cpu_num;
> +             cpu_num++;
> +     }
> +
> +    return -1;
> +}
> +EXPORT_SYMBOL(xen_pcpu_index);
> +
>  /*
>   * Sync dom0's pcpu information with xen hypervisor's
>   */
> @@ -417,4 +449,4 @@ static int __init xen_pcpu_init(void)
>       return err;
>  }
>  
> -subsys_initcall(xen_pcpu_init);
> +arch_initcall(xen_pcpu_init);
> diff --git a/include/xen/pcpu.h b/include/xen/pcpu.h
> index fb2bf6b..7e8f9d1 100644
> --- a/include/xen/pcpu.h
> +++ b/include/xen/pcpu.h
> @@ -27,4 +27,6 @@ static inline int xen_pcpu_online(uint32_t flags)
>  extern int register_xen_pcpu_notifier(struct notifier_block *nb);
>  
>  extern void unregister_xen_pcpu_notifier(struct notifier_block *nb);
> +
> +extern int xen_pcpu_index(uint32_t acpi_id, int is_acpiid);
>  #endif
>
>
>
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@xxxxxxxxxxxxxxxxxxx
> http://lists.xensource.com/xen-devel


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel