Re: [Xen-devel] [PATCH] xen: Add comment for missing FROZEN notifier transitions

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From	Boris Ostrovsky <boris.ostrovsky@oracle.com>
Newsgroups	linux.kernel
Subject	Re: [Xen-devel] [PATCH] xen: Add comment for missing FROZEN notifier transitions
Date	Mon, 04 Apr 2016 18:50:02 +0200
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On 04/04/2016 12:30 PM, David Vrabel wrote:
> On 04/04/16 17:21, Julien Grall wrote:
>> (CC Stefano new e-mail address)
>>
>> Hello Anna-Maria,
>>
>> On 04/04/2016 13:32, Anna-Maria Gleixner wrote:
>>> Xen guests do not offline/online CPUs during suspend/resume and
>>> therefore FROZEN notifier transitions are not required. Add this
>>> explanation as a comment in the code to get not confused why
>>> CPU_TASKS_FROZEN masked transitions are not considered.
> Alternatively, these could be added even if they are not encountered.
> This might be more future-proof but the documentation might be clearer.
>
> Boris, Juergen, any opinion?

Wouldn't the same comment need to be added to xen_hvm_cpu_notify()?


-boris


>
> David>> --- a/drivers/xen/events/events_fifo.c
>>> +++ b/drivers/xen/events/events_fifo.c
>>> @@ -425,6 +425,12 @@ static int evtchn_fifo_cpu_notification(
>>>        int cpu = (long)hcpu;
>>>        int ret = 0;
>>>
>>> +    /*
>>> +     * Xen guests do not offline/online CPUs during
>>> +     * suspend/resume, thus CPU_TASKS_FROZEN masked transitions
>>> +     * are not considered.
>>> +    */
>> NIT: The '*' is not aligned with the others.
> If this doesn't need any other changes, I'll fix this on commit.
>
> David

Thread

[PATCH] xen: Add comment for missing FROZEN notifier transitions Anna-Maria Gleixner <anna-maria@linutronix.de> - 2016-04-04 14:40 +0200
  Re: [Xen-devel] [PATCH] xen: Add comment for missing FROZEN notifier  transitions Julien Grall <julien.grall@arm.com> - 2016-04-04 18:30 +0200
    Re: [Xen-devel] [PATCH] xen: Add comment for missing FROZEN notifier  transitions David Vrabel <david.vrabel@citrix.com> - 2016-04-04 18:40 +0200
      Re: [Xen-devel] [PATCH] xen: Add comment for missing FROZEN notifier  transitions Boris Ostrovsky <boris.ostrovsky@oracle.com> - 2016-04-04 18:50 +0200
        Re: [Xen-devel] [PATCH] xen: Add comment for missing FROZEN notifier  transitions Juergen Gross <jgross@suse.com> - 2016-04-05 06:30 +0200
          Re: [Xen-devel] [PATCH] xen: Add comment for missing FROZEN notifier  transitions Stefano Stabellini <sstabellini@kernel.org> - 2016-04-07 02:00 +0200
  Re: [Xen-devel] [PATCH] xen: Add comment for missing FROZEN notifier  transitions David Vrabel <dvrabel@cantab.net> - 2016-04-06 15:20 +0200
    Re: [PREEMPT-RT] [Xen-devel] [PATCH] xen: Add comment for missing  FROZEN notifier transitions Anna-Maria Gleixner <anna-maria@linutronix.de> - 2016-04-06 16:10 +0200
    Re: [Xen-devel] [PATCH] xen: Add comment for missing FROZEN notifier  transitions Stefano Stabellini <sstabellini@kernel.org> - 2016-04-07 02:00 +0200

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