On Wed, Jun 15, 2011 at 1:41 PM, DRAM Ninjas <[email protected]> wrote:

> Getting back to this question -- what happens if the -corefreq parameter in
> simconfig doesn't match PTLSIM_FREQ and core_freq_hz? core_freq_hz is
> primarily used by the scheduler, right? If there's a mismatch between the
> parameters, does that mean that the length of a time slice is going to be
> messed up?
>
> If you are talking about kernel scheduler then no. It uses 'rdtsc' and
other hpet IO to read system time/clock cycles. Both rdtsc and hpet use same
clock for reference. This clock runs with PTLSIM_FREQ in simulation mode so
length of a time slice is not going to be messed up. I looked at
configuration options and all the options from 'Timer and Interrupt' section
is not used and should be removed.

- Avadh

>
>
> On Wed, Jun 8, 2011 at 8:56 PM, Hz Xes <[email protected]> wrote:
>
>>  Hi Avadh,
>>
>> Thanks a  lot for reply! And Please correct me if my understanding is
>> wrong.
>>
>> PTLSIM_FREQ defined in "vl.c" is actually real clock used by both PTLsim
>> and and Qemu when Marss enters the simulation mode. And It is necessary that
>> we make qemu clock same as the ptlsim clock for the correctness of
>> simulation. Is my understanding right? And, for making core_freq_hz
>> configurable, the place I need to change is the function call of
>> "cpu_get_sim_clock()" in "vl.c" to replace the hardcoded PTLSIM_FREQ by
>> core_freq_hz input. Could you reminder me if anywhere else I have to change
>> to make core_freq_hz configurable?
>>
>> Thanks,
>> HZ
>>
>>
>>
>> ------------------------------
>> *From:* avadh patel <[email protected]>
>> *To:* Hz Xes <[email protected]>
>> *Cc:* "[email protected]" <[email protected]>
>> *Sent:* Wed, June 8, 2011 2:25:09 PM
>> *Subject:* Re: [marss86-devel] can not change cpu core frequency by the
>> parameter of core_freq_hz
>>
>> Core frequency is hardcoded in qemu/vl.c (qemu/qemu-timer.c for
>> qemu-0.14) file for simulation mode.
>> Look for PTLsim_freq.
>>
>> - Avadh
>>
>> On Wednesday, June 8, 2011, Hz Xes <[email protected]> wrote:
>> > Are there anybody have similar problem or I just made a mistake on
>> configuration or somewhere else?
>> >
>> > Thanks
>> > HZ
>>
>> _______________________________________________
>> http://www.marss86.org
>> Marss86-Devel mailing list
>> [email protected]
>> https://www.cs.binghamton.edu/mailman/listinfo/marss86-devel
>>
>>
>
> _______________________________________________
> http://www.marss86.org
> Marss86-Devel mailing list
> [email protected]
> https://www.cs.binghamton.edu/mailman/listinfo/marss86-devel
>
>
_______________________________________________
http://www.marss86.org
Marss86-Devel mailing list
[email protected]
https://www.cs.binghamton.edu/mailman/listinfo/marss86-devel

Reply via email to