Re: [PATCH v2 2/2] xentrace: Add TRC_HVM_VCHIP

[Don Slutz <dslutz@verizon.com>]

On 04/01/14 09:23, George Dunlap wrote:
> On 03/28/2014 04:56 PM, Don Slutz wrote:
>> This add a set of trace events that track the setup of various
>> virtual chips related to timers in domU.

[snip]

>> @@ -255,6 +257,9 @@ static void hpet_set_timer(HPETState *h, unsigned int tn)
>>        * being enabled (now).
>>        */
>>       oneshot = !timer_is_periodic(h, tn);
>> +    TRACE_4D(TRC_HVM_VCHIP_HPET_START_TIMER, tn, irq,
>> +             hpet_tick_to_ns(h, diff),
>
> This will only be 32 bits wide; is there ever any risk that this may exceed 4 seconds (4 billion nanoseconds)?
>

Yes.  Will change to pass these all as 2 values.  I see no reason to set TRC_64_FLAG since these will allways be 64 bit values.

Will also see about using TRC_PAR_LONG(). And switch to hex in formats.

>
>> diff --git a/xen/include/public/trace.h b/xen/include/public/trace.h
>> index e2f60a6..410f0fe 100644
>> --- a/xen/include/public/trace.h
>> +++ b/xen/include/public/trace.h
>> @@ -52,6 +52,7 @@
>>   /* trace subclasses for SVM */
>>   #define TRC_HVM_ENTRYEXIT 0x00081000   /* VMENTRY and #VMEXIT       */
>>   #define TRC_HVM_HANDLER   0x00082000   /* various HVM handlers      */
>> +#define TRC_HVM_VCHIP     0x00084000   /* virtual chips */
>
> Maybe TRC_HVM_EMUL, for emulated devices?
>

That would be fine with me.  Just going to wait to see if any other comments on the name.

    -Don Slutz

>  -George
>