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

[David Vrabel]

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?

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