From mboxrd@z Thu Jan  1 00:00:00 1970
From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Subject: Re: [PATCH] x86/cpuidle: don't count C1 multiple times
Date: Mon, 24 Nov 2014 11:36:22 -0500
Message-ID: <20141124163622.GA7449@laptop.dumpdata.com>
References: <547328E0020000780004A4A1@mail.emea.novell.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Return-path: <xen-devel-bounces@lists.xen.org>
Received: from mail6.bemta4.messagelabs.com ([85.158.143.247])
	by lists.xen.org with esmtp (Exim 4.72)
	(envelope-from <konrad.wilk@oracle.com>) id 1Xswcl-0003z0-UI
	for xen-devel@lists.xenproject.org; Mon, 24 Nov 2014 16:36:28 +0000
Content-Disposition: inline
In-Reply-To: <547328E0020000780004A4A1@mail.emea.novell.com>
List-Unsubscribe: <http://lists.xen.org/cgi-bin/mailman/options/xen-devel>,
	<mailto:xen-devel-request@lists.xen.org?subject=unsubscribe>
List-Post: <mailto:xen-devel@lists.xen.org>
List-Help: <mailto:xen-devel-request@lists.xen.org?subject=help>
List-Subscribe: <http://lists.xen.org/cgi-bin/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xen.org?subject=subscribe>
Sender: xen-devel-bounces@lists.xen.org
Errors-To: xen-devel-bounces@lists.xen.org
To: Jan Beulich <JBeulich@suse.com>
Cc: xen-devel <xen-devel@lists.xenproject.org>
List-Id: xen-devel@lists.xenproject.org

On Mon, Nov 24, 2014 at 11:47:28AM +0000, Jan Beulich wrote:
> Commit 4ca6f9f0 ("x86/cpuidle: publish new states only after fully
> initializing them") resulted in the state counter to be incremented
> for C1 despite that using a fixed table entry (and the statically
> initialized counter value already accounting for it and C0).
> 

Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reported-by: Steve Freitas <sflist@ihonk.com>
Release-Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
(thought it would be good to get from Steve an confirmation that this
fixes it - which I believe is 99% the case).

> Signed-off-by: Jan Beulich <jbeulich@suse.com>
> 
> --- a/xen/arch/x86/acpi/cpu_idle.c
> +++ b/xen/arch/x86/acpi/cpu_idle.c
> @@ -1015,7 +1015,7 @@ static void set_cx(
>      cx->target_residency = cx->latency * latency_factor;
>  
>      smp_wmb();
> -    acpi_power->count++;
> +    acpi_power->count += (cx->type != ACPI_STATE_C1);
>      if ( cx->type == ACPI_STATE_C1 || cx->type == ACPI_STATE_C2 )
>          acpi_power->safe_state = cx;
>  }
> 
> 
> 

> x86/cpuidle: don't count C1 multiple times
> 
> Commit 4ca6f9f0 ("x86/cpuidle: publish new states only after fully
> initializing them") resulted in the state counter to be incremented
> for C1 despite that using a fixed table entry (and the statically
> initialized counter value already accounting for it and C0).
> 
> Signed-off-by: Jan Beulich <jbeulich@suse.com>
> 
> --- a/xen/arch/x86/acpi/cpu_idle.c
> +++ b/xen/arch/x86/acpi/cpu_idle.c
> @@ -1015,7 +1015,7 @@ static void set_cx(
>      cx->target_residency = cx->latency * latency_factor;
>  
>      smp_wmb();
> -    acpi_power->count++;
> +    acpi_power->count += (cx->type != ACPI_STATE_C1);
>      if ( cx->type == ACPI_STATE_C1 || cx->type == ACPI_STATE_C2 )
>          acpi_power->safe_state = cx;
>  }