From mboxrd@z Thu Jan  1 00:00:00 1970
From: Juergen Gross <jgross@suse.com>
Subject: Re: [PATCH 4/9] xen: sched: add .init_pdata hook to the
 scheduler interface
Date: Thu, 1 Oct 2015 09:43:59 +0200
Message-ID: <560CE43F.3030809@suse.com>
References: <20150929164726.17589.96920.stgit@Solace.station>
	<20150929165556.17589.62924.stgit@Solace.station>
	<560CC2EC.6030801@suse.com> <1443681197.3276.163.camel@citrix.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"; Format="flowed"
Content-Transfer-Encoding: 7bit
Return-path: <xen-devel-bounces@lists.xen.org>
Received: from mail6.bemta5.messagelabs.com ([195.245.231.135])
	by lists.xen.org with esmtp (Exim 4.72)
	(envelope-from <jgross@suse.com>) id 1ZhYX7-0005bK-IW
	for xen-devel@lists.xenproject.org; Thu, 01 Oct 2015 07:44:05 +0000
In-Reply-To: <1443681197.3276.163.camel@citrix.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: Dario Faggioli <dario.faggioli@citrix.com>, xen-devel@lists.xenproject.org
Cc: George Dunlap <george.dunlap@eu.citrix.com>
List-Id: xen-devel@lists.xenproject.org

On 10/01/2015 08:33 AM, Dario Faggioli wrote:
> On Thu, 2015-10-01 at 07:21 +0200, Juergen Gross wrote:
>> On 09/29/2015 06:55 PM, Dario Faggioli wrote:
>
>>> --- a/xen/common/schedule.c
>>> +++ b/xen/common/schedule.c
>>> @@ -1407,6 +1407,9 @@ static int cpu_schedule_callback(
>>>
>>>        switch ( action )
>>>        {
>>> +    case CPU_STARTING:
>>> +        SCHED_OP(&ops, init_pdata, cpu);
>>> +        break;
>>>        case CPU_UP_PREPARE:
>>>            rc = cpu_schedule_up(cpu);
>>>            break;
>>> @@ -1484,6 +1487,7 @@ void __init scheduler_init(void)
>>>        if ( ops.alloc_pdata &&
>>>             !(this_cpu(schedule_data).sched_priv =
>>> ops.alloc_pdata(&ops, 0)) )
>>>            BUG();
>>> +    SCHED_OP(&ops, init_pdata, 0);
>>
>> You can't call this without having it set in all schedulers.
>>
>> I guess using the init_pdata hook has to be introduced after or in
>> patch 5.
>>
> But, if it is not set, it is NULL, in which case, SCHED_OP does the
> trick for me, doesn't it?
>
> #define SCHED_OP(opsptr, fn, ...)                                          \
>           (( (opsptr)->fn != NULL ) ? (opsptr)->fn(opsptr, ##__VA_ARGS__ )  \
>            : (typeof((opsptr)->fn(opsptr, ##__VA_ARGS__)))0 )

Aah, yes, of course.

Sorry for the noise.


Juergen