Unfortunately what I've found is that the O3 dynamic thread creation
code is broken, beyond a quick fix.  I'll try and file a bug report on
it with more details later.

Steve

On Tue, Jun 24, 2008 at 8:51 AM, Sujay Phadke <[EMAIL PROTECTED]> wrote:
> Thanks for looking into it Steve. Let me know if you find anything.
>
> ----- Original Message -----
> From: "Steve Reinhardt" <[EMAIL PROTECTED]>
> To: "M5 users mailing list" <[email protected]>
> Sent: Monday, June 23, 2008 11:57 PM
> Subject: Re: [m5-users] error running O3 directly with more than 1 cpu
>
>
>> OK, I tracked it down a little further... the problem with having O3
>> initialize threads to Unallocated is in the activate() method in
>> cpu/o3/thread_context_impl.hh, where the CPU checks to make sure that
>> there are enough resources to activate a thread if it's in Unallocated
>> state (as opposed to Suspended state, where it assumes those resources
>> are already allocated).  There must be a bug in that code since even
>> if the very first thread is in Unallocated it still doesn't start up
>> properly.  However there's potentially a more general problem if the
>> CPU doesn't reserve the physical registers for a thread from the very
>> beginning.  I'll keep probing as time permits...
>>
>> Steve
>>
>> On Mon, Jun 23, 2008 at 8:41 PM, Steve Reinhardt <[EMAIL PROTECTED]> wrote:
>>> It's a bug in M5.  The SE threading code expects the "idle" contexts
>>> to be in state Unallocated (see nxm_thread_createFunc in
>>> src/kern/tru64/tru64.hh), which is what SimpleCPU does.  However O3
>>> initializes unused threads to Suspended (see
>>> src/cpu/o3/alpha/cpu_impl.hh).  Unfortunately just changing the O3
>>> initialization to Suspended caused other problems which I haven't
>>> figured out yet.
>>>
>>> Steve
>>>
>>> On Mon, Jun 23, 2008 at 2:47 PM, Sujay Phadke <[EMAIL PROTECTED]>
>>> wrote:
>>>> Well I wanted to run the O3 (n>1) for testing wattch. Is it wrong to run
>>>> it
>>>> in detailed mode directly w/o using any switching?
>>>> If so, can you give me an example file and command line which does
>>>> switching
>>>> for say Splash2?
>>>>
>>>> thanks,
>>>> Sujay
>>>>
>>>> ----- Original Message -----
>>>> From: "Ali Saidi" <[EMAIL PROTECTED]>
>>>> To: "M5 users mailing list" <[email protected]>
>>>> Sent: Monday, June 23, 2008 5:39 PM
>>>> Subject: Re: [m5-users] error running O3 directly with more than 1 cpu
>>>>
>>>>
>>>>>
>>>>> On Jun 23, 2008, at 1:23 PM, Sujay Phadke wrote:
>>>>>
>>>>>> Hello,
>>>>>>         If I try to run O3 in SE mode directly, without using any
>>>>>> fastforwarding, it gives me the error:
>>>>>>
>>>>>>  build/ALPHA_SE/m5.opt configs/splash2/runsplash.py -d -n4 -b
>>>>>> OceanContig
>>>>>>
>>>>>> warn: Increasing stack size by one page.
>>>>>> warn: ignoring syscall sigprocmask(3, 18446744073709551615, ...)
>>>>>> warn: ignoring syscall sigprocmask(3, 0, ...)
>>>>>> warn: ignoring syscall sigaction(8, 4831387552, ...)
>>>>>> warn: ignoring syscall sigaction(11, 4831387552, ...)
>>>>>> warn: ignoring syscall sigaction(10, 4831387552, ...)
>>>>>> warn: ignoring syscall sigaction(4, 4831387552, ...)
>>>>>> warn: ignoring syscall sigaction(7, 4831387552, ...)
>>>>>> warn: ignoring syscall sigaction(6, 4831387552, ...)
>>>>>> warn: ignoring syscall sigaction(12, 4831387552, ...)
>>>>>> warn: ignoring syscall sigaction(5, 4831387552, ...)
>>>>>> warn: ignoring syscall sigaction(13, 4831387552, ...)
>>>>>> nxm_thread_create: no idle contexts available.
>>>>>> Program aborted at cycle 378945000
>>>>>> It works fine of numcpus (-n) = 1, or if I use atomic or timing
>>>>>> mode. The statement
>>>>>>
>>>>>> thread->setStatus(ThreadContext::Unallocated);
>>>>>>
>>>>>> appears in src/cpu/simple/base.cc and src/cpu/o3/
>>>>>> thread_context_impl.hh.
>>>>>>
>>>>> The statement and the context the statement is in are two different
>>>>> things. From a cursory look of the O3CPU, it appears as though the
>>>>> state of the thread context is never initialized when the thread
>>>>> context is created, and the places where it is set to unallocated are
>>>>> for switching CPUs. Initializing it to Unallocated should solve the
>>>>> problem.
>>>>>
>>>>> Are you planning on running a detailed CPU for the entirety of the
>>>>> benchmark?
>>>>>
>>>>> Ali
>>>>>
>>>>> _______________________________________________
>>>>> m5-users mailing list
>>>>> [email protected]
>>>>> http://m5sim.org/cgi-bin/mailman/listinfo/m5-users
>>>>>
>>>>
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