Patchwork [1/4] hotplug, x86: Fix online state in cpu0 debug interface

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Submitter Toshi Kani
Date Aug. 17, 2013, 7:46 p.m.
Message ID <1376768819-28975-2-git-send-email-toshi.kani@hp.com>
Download mbox | patch
Permalink /patch/267997/
State Not Applicable
Headers show

Comments

Toshi Kani - Aug. 17, 2013, 7:46 p.m.
_debug_hotplug_cpu() is a debug interface that puts cpu0 offline during
boot-up when CONFIG_DEBUG_HOTPLUG_CPU0 is set.  After cpu0 is put offline
in this interface, however, /sys/devices/system/cpu/cpu0/online still
shows 1 (online).

This patch fixes _debug_hotplug_cpu() to update dev->offline when CPU
online/offline operation succeeded.

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
---
 arch/x86/kernel/topology.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)
Rafael J. Wysocki - Aug. 18, 2013, 12:59 a.m.
On Saturday, August 17, 2013 01:46:56 PM Toshi Kani wrote:
> _debug_hotplug_cpu() is a debug interface that puts cpu0 offline during
> boot-up when CONFIG_DEBUG_HOTPLUG_CPU0 is set.  After cpu0 is put offline
> in this interface, however, /sys/devices/system/cpu/cpu0/online still
> shows 1 (online).
> 
> This patch fixes _debug_hotplug_cpu() to update dev->offline when CPU
> online/offline operation succeeded.
> 
> Signed-off-by: Toshi Kani <toshi.kani@hp.com>

Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

> ---
>  arch/x86/kernel/topology.c |    7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/x86/kernel/topology.c b/arch/x86/kernel/topology.c
> index 6e60b5f..5823bbd 100644
> --- a/arch/x86/kernel/topology.c
> +++ b/arch/x86/kernel/topology.c
> @@ -72,16 +72,19 @@ int __ref _debug_hotplug_cpu(int cpu, int action)
>  		ret = cpu_down(cpu);
>  		if (!ret) {
>  			pr_info("CPU %u is now offline\n", cpu);
> +			dev->offline = true;
>  			kobject_uevent(&dev->kobj, KOBJ_OFFLINE);
>  		} else
>  			pr_debug("Can't offline CPU%d.\n", cpu);
>  		break;
>  	case 1:
>  		ret = cpu_up(cpu);
> -		if (!ret)
> +		if (!ret) {
> +			dev->offline = false;
>  			kobject_uevent(&dev->kobj, KOBJ_ONLINE);
> -		else
> +		} else {
>  			pr_debug("Can't online CPU%d.\n", cpu);
> +		}
>  		break;
>  	default:
>  		ret = -EINVAL;
> --
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Patch

diff --git a/arch/x86/kernel/topology.c b/arch/x86/kernel/topology.c
index 6e60b5f..5823bbd 100644
--- a/arch/x86/kernel/topology.c
+++ b/arch/x86/kernel/topology.c
@@ -72,16 +72,19 @@  int __ref _debug_hotplug_cpu(int cpu, int action)
 		ret = cpu_down(cpu);
 		if (!ret) {
 			pr_info("CPU %u is now offline\n", cpu);
+			dev->offline = true;
 			kobject_uevent(&dev->kobj, KOBJ_OFFLINE);
 		} else
 			pr_debug("Can't offline CPU%d.\n", cpu);
 		break;
 	case 1:
 		ret = cpu_up(cpu);
-		if (!ret)
+		if (!ret) {
+			dev->offline = false;
 			kobject_uevent(&dev->kobj, KOBJ_ONLINE);
-		else
+		} else {
 			pr_debug("Can't online CPU%d.\n", cpu);
+		}
 		break;
 	default:
 		ret = -EINVAL;