* Re: [Qemu-devel] Qemu workstation
@ 2004-04-05 15:19 Mike Nordell
2004-04-05 20:40 ` Filip Navara
0 siblings, 1 reply; 26+ messages in thread
From: Mike Nordell @ 2004-04-05 15:19 UTC (permalink / raw)
To: qemu-devel
Browsing the archives I spotted something I wanted to comment on.
John R. Hogerhuis wrote:
> More like saying the Win32 version is probably vaporware (i.e.
> implementation not complete, with initial mock-up of running
> system for marketing purposes).
As I've talked to a person on IRC presenting itself as the author, the
information I got was that the thing at the .co.uk site is a Visual Basic
application that works by hijacking the SDL window from the QEMU process and
displaying it as if it was its own output.
Possibly that's where the 733MHz CPU and 500MB free harddisk space
requirments (http://www.revenitor.co.uk/qews.asp) might be from...
As for running ReactOS under QEMU (on Win32); yes, I have run it.
/Mike
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Qemu workstation
2004-04-05 15:19 [Qemu-devel] Qemu workstation Mike Nordell
@ 2004-04-05 20:40 ` Filip Navara
2004-04-05 21:05 ` John R. Hogerhuis
0 siblings, 1 reply; 26+ messages in thread
From: Filip Navara @ 2004-04-05 20:40 UTC (permalink / raw)
To: qemu-devel
Mike Nordell wrote:
>As for running ReactOS under QEMU (on Win32); yes, I have run it.
>
>
+1
I'm running it inside QEMU everyday.
- Filip
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Qemu workstation
2004-04-05 20:40 ` Filip Navara
@ 2004-04-05 21:05 ` John R. Hogerhuis
2004-04-05 21:15 ` Filip Navara
2004-04-05 21:15 ` [Qemu-devel] " Martin Fuchs
0 siblings, 2 replies; 26+ messages in thread
From: John R. Hogerhuis @ 2004-04-05 21:05 UTC (permalink / raw)
To: qemu-devel
[-- Attachment #1: Type: text/plain, Size: 248 bytes --]
Okay first it seems I was largely wrong about this shell... it seems
that although it is not complete it is not vaporware (apologies to Alex)
Filip, are you running the windows port from CVS? Or are you running
ReactOS from QEMU under Linux?
[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 189 bytes --]
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Qemu workstation
2004-04-05 21:05 ` John R. Hogerhuis
@ 2004-04-05 21:15 ` Filip Navara
2004-04-05 21:15 ` [Qemu-devel] " Martin Fuchs
1 sibling, 0 replies; 26+ messages in thread
From: Filip Navara @ 2004-04-05 21:15 UTC (permalink / raw)
To: jhoger, qemu-devel
John R. Hogerhuis wrote:
>Filip, are you running the windows port from CVS? Or are you running
>ReactOS from QEMU under Linux?
>
>
I'm running the Windows port from CVS with some local fixes (i think
most of then appered on the mailing list already) and I also the tried
the port made by Mike Nordell with similar results.
- Filip
^ permalink raw reply [flat|nested] 26+ messages in thread
* [Qemu-devel] Re: Qemu workstation
2004-04-05 21:05 ` John R. Hogerhuis
2004-04-05 21:15 ` Filip Navara
@ 2004-04-05 21:15 ` Martin Fuchs
2004-04-05 21:40 ` John R. Hogerhuis
2004-04-05 22:12 ` Filip Navara
1 sibling, 2 replies; 26+ messages in thread
From: Martin Fuchs @ 2004-04-05 21:15 UTC (permalink / raw)
To: qemu-devel
Hi,
On 05.04.2004 23:05:10 John R. Hogerhuis wrote:
> Okay first it seems I was largely wrong about this shell... it seems
> that although it is not complete it is not vaporware (apologies to Alex)
>
> Filip, are you running the windows port from CVS? Or are you running
> ReactOS from QEMU under Linux?
Where can the WIN32 port be downloaded?
Thanks,
Martin
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Re: Qemu workstation
2004-04-05 21:15 ` [Qemu-devel] " Martin Fuchs
@ 2004-04-05 21:40 ` John R. Hogerhuis
2004-04-05 22:12 ` Filip Navara
1 sibling, 0 replies; 26+ messages in thread
From: John R. Hogerhuis @ 2004-04-05 21:40 UTC (permalink / raw)
To: qemu-devel
[-- Attachment #1: Type: text/plain, Size: 482 bytes --]
Martin --
You must build Win32 port from CVS AFAIK. It has patches from Kazu and I
think some from Mike as well.
I made an effort to get it to cross compile (Debian Mingw32), but the
last time I tried it, the end product silently exits without doing
anything. When I have a chance I am going to debug it and figure out
what's up.
Others have been building on the MSYS/Mingw32 under windows, you should
have better luck in that environment.
Later,
-- John.
[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 189 bytes --]
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Re: Qemu workstation
2004-04-05 21:15 ` [Qemu-devel] " Martin Fuchs
2004-04-05 21:40 ` John R. Hogerhuis
@ 2004-04-05 22:12 ` Filip Navara
1 sibling, 0 replies; 26+ messages in thread
From: Filip Navara @ 2004-04-05 22:12 UTC (permalink / raw)
To: qemu-devel
Martin Fuchs wrote:
>Where can the WIN32 port be downloaded?
>
>
You can get my binaries from www.volny.cz/xnavara/qemu.zip. It's build
from today's CVS with two changes:
- Commented out code for translating scancodes, because it's not needed
on WIN32.
- Make the application a console type, so I can see the help. (And close
the console on normal run.)
- Filip
^ permalink raw reply [flat|nested] 26+ messages in thread
* [Qemu-devel] Qemu workstation
@ 2004-04-05 8:47 Jean-Michel POURE
2004-04-05 9:10 ` John R. Hogerhuis
0 siblings, 1 reply; 26+ messages in thread
From: Jean-Michel POURE @ 2004-04-05 8:47 UTC (permalink / raw)
To: qemu-devel
Dear all,
Just a quick note to inform that according to the wiki
(http://am.xs4all.nl/phpwiki/index.php/Qemu),
some work is being done to produce frontends to Qemu:
Win32 --> http://www.revenitor.co.uk/qews.asp
GNU/Linux --> http://am.xs4all.nl/phpwiki/index.php/QemuWorkstation
Cheers, Jean-Michel
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Qemu workstation
2004-04-05 8:47 [Qemu-devel] " Jean-Michel POURE
@ 2004-04-05 9:10 ` John R. Hogerhuis
2004-04-05 9:30 ` Rudi Lippert
2004-04-05 9:38 ` Jean-Michel POURE
0 siblings, 2 replies; 26+ messages in thread
From: John R. Hogerhuis @ 2004-04-05 9:10 UTC (permalink / raw)
To: qemu-devel
[-- Attachment #1: Type: text/plain, Size: 540 bytes --]
Sweet Jesus... a new name, vmware shell look alike (not a step in the
right direction IMHO... we could probably come up with a better UI than
to rehash vmware's...) and the win32 port is not really operational yet
(unless 0.5.3 actually made it process .iso files... I haven't built
yet...)
Well I guess there's something to be said for multi-tasking.
Does anyone know who this is? I'd like to find out what kind of magic
they are performing to get ReactOS running in win32 port.
Alas I suspect GIMP at work...
-- John.
[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 189 bytes --]
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Qemu workstation
2004-04-05 9:10 ` John R. Hogerhuis
@ 2004-04-05 9:30 ` Rudi Lippert
2004-04-05 9:55 ` Jean-Michel POURE
2004-04-05 9:38 ` Jean-Michel POURE
1 sibling, 1 reply; 26+ messages in thread
From: Rudi Lippert @ 2004-04-05 9:30 UTC (permalink / raw)
To: jhoger, qemu-devel
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
i agree. i don't know anything about the windows port, but personally, i think
the draft of the linux-frontend looks more functional.
one thing about multitasking: there should probably be an option in the
preferences dialog allowing to STOP the vm as soon as the focus goes to
another one and to CONT that one. that would definitely be a step ahead of
vmware, since they don't allow stopping a vm without dumping the memory to
the hd.
it is probably too early to talk about these things, but it came to my mind
today, so why not post it today.
another question: are there sources available for the linux frontend? many
people on this list will also test the frontend, which would certainly speed
up its development.
€0.06
"Re: [Qemu-devel] Qemu workstation" (John R. Hogerhuis, Monday 05 April 2004
11:10):
> Sweet Jesus... a new name, vmware shell look alike (not a step in the
> right direction IMHO... we could probably come up with a better UI than
> to rehash vmware's...) and the win32 port is not really operational yet
> (unless 0.5.3 actually made it process .iso files... I haven't built
> yet...)
>
> Well I guess there's something to be said for multi-tasking.
>
> Does anyone know who this is? I'd like to find out what kind of magic
> they are performing to get ReactOS running in win32 port.
>
> Alas I suspect GIMP at work...
>
> -- John.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.4 (GNU/Linux)
iD8DBQFAcScc1nTg39QS/TsRAt72AJ4wGaL9c/iwA+a7R8dL5qznUZVf7ACeJtDs
v4GGCxmFBog9WbCrmLO7DHg=
=mdod
-----END PGP SIGNATURE-----
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Qemu workstation
2004-04-05 9:30 ` Rudi Lippert
@ 2004-04-05 9:55 ` Jean-Michel POURE
2004-04-05 19:31 ` Fabrice Bellard
0 siblings, 1 reply; 26+ messages in thread
From: Jean-Michel POURE @ 2004-04-05 9:55 UTC (permalink / raw)
To: qemu-devel; +Cc: Rudi Lippert
Le lundi 5 Avril 2004 11:30, Rudi Lippert a écrit :
> another question: are there sources available for the linux frontend? many
> people on this list will also test the frontend, which would certainly
> speed up its development.
> €0.06
Dear Rudi,
I contacted Alex on Morphix mailing list about this issue. My post is:
http://www.morphix.org/modules/newbb/viewtopic.php?topic_id=1239&forum=3&jump=1
Cheers,
Jean-Michel
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Qemu workstation
2004-04-05 9:55 ` Jean-Michel POURE
@ 2004-04-05 19:31 ` Fabrice Bellard
2004-04-05 21:49 ` Jamie Burns
0 siblings, 1 reply; 26+ messages in thread
From: Fabrice Bellard @ 2004-04-05 19:31 UTC (permalink / raw)
To: jm, qemu-devel; +Cc: Rudi Lippert
Hi,
I am interested by a GTK GUI for QEMU and I think it should be commited
in the main QEMU CVS.
Some notes about the GUI:
- Avoid using SDL or SDL wrappers: it is simpler to use plain GTK or GDK
to draw the VGA frame buffer.
- I am not sure that handling multiple VMs running at the same time is
very useful (some architectural changes are needed in QEMU). But
switching easily between VM configurations seems interesting.
- The VM description management must be integrated in the QEMU core. I
plan to work on it soon (Renzo Davoli sent patch I need to study).
- The VM console should be available in a separate TAB for the hackers !
- Of course there should be commands to eject/insert medias, to change
the hard disk images and to update the VM configuration (ideally a
simple dialog for dummies and a more technical one to change IRQs, IO
ports, number of interfaces).
Fabrice.
Jean-Michel POURE wrote:
> Le lundi 5 Avril 2004 11:30, Rudi Lippert a écrit :
>
>>another question: are there sources available for the linux frontend? many
>>people on this list will also test the frontend, which would certainly
>>speed up its development.
>>€0.06
>
>
> Dear Rudi,
>
> I contacted Alex on Morphix mailing list about this issue. My post is:
> http://www.morphix.org/modules/newbb/viewtopic.php?topic_id=1239&forum=3&jump=1
>
> Cheers,
> Jean-Michel
>
>
> _______________________________________________
> Qemu-devel mailing list
> Qemu-devel@nongnu.org
> http://mail.nongnu.org/mailman/listinfo/qemu-devel
>
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Qemu workstation
2004-04-05 19:31 ` Fabrice Bellard
@ 2004-04-05 21:49 ` Jamie Burns
2004-04-06 12:17 ` Richard Zidlicky
2004-04-06 19:00 ` Fabrice Bellard
0 siblings, 2 replies; 26+ messages in thread
From: Jamie Burns @ 2004-04-05 21:49 UTC (permalink / raw)
To: qemu-devel
> I am not sure that handling multiple VMs running at the same time is
> very useful (some architectural changes are needed in QEMU). But
> switching easily between VM configurations seems interesting.
I think that multiple VM's is a worthy goal as long as you can minimise CPU
usage. Having multiple VM's gives you the ability to do some very cool
things. I use VMWARE in Windows and sometimes have both Linux and FreeBSD
running in VM's so I can test software against all 3 OS's at once. I imagine
it would be very useful to developers of cluster software.
I tried the Win32 port the other day, running Linux, and it sat using 100%
of the CPU whilst doing next to nothing at a command prompt. Using VMWARE,
and waiting at a command prompt uses very little CPU time.
Is QEMU sat in a busy loop all the time?
Jamie.
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Qemu workstation
2004-04-05 21:49 ` Jamie Burns
@ 2004-04-06 12:17 ` Richard Zidlicky
2004-04-06 13:28 ` Brad Campbell
2004-04-06 14:00 ` Jamie Burns
2004-04-06 19:00 ` Fabrice Bellard
1 sibling, 2 replies; 26+ messages in thread
From: Richard Zidlicky @ 2004-04-06 12:17 UTC (permalink / raw)
To: qemu-devel
On Mon, Apr 05, 2004 at 10:49:51PM +0100, Jamie Burns wrote:
> > I am not sure that handling multiple VMs running at the same time is
> > very useful (some architectural changes are needed in QEMU). But
> > switching easily between VM configurations seems interesting.
>
> I think that multiple VM's is a worthy goal as long as you can minimise CPU
> usage. Having multiple VM's gives you the ability to do some very cool
> things. I use VMWARE in Windows and sometimes have both Linux and FreeBSD
> running in VM's so I can test software against all 3 OS's at once. I imagine
> it would be very useful to developers of cluster software.
>
> I tried the Win32 port the other day, running Linux, and it sat using 100%
> of the CPU whilst doing next to nothing at a command prompt. Using VMWARE,
> and waiting at a command prompt uses very little CPU time.
>
> Is QEMU sat in a busy loop all the time?
it is not QEMU but the hosted OS that is in the busy loop. QEMU
will have to recognise "idle loops" to fix this - this could be
really tricky.
Richard
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Qemu workstation
2004-04-06 12:17 ` Richard Zidlicky
@ 2004-04-06 13:28 ` Brad Campbell
2004-04-06 20:23 ` Filip Navara
2004-04-06 14:00 ` Jamie Burns
1 sibling, 1 reply; 26+ messages in thread
From: Brad Campbell @ 2004-04-06 13:28 UTC (permalink / raw)
To: qemu-devel
Richard Zidlicky wrote:
> On Mon, Apr 05, 2004 at 10:49:51PM +0100, Jamie Burns wrote:
>
>>>I am not sure that handling multiple VMs running at the same time is
>>>very useful (some architectural changes are needed in QEMU). But
>>>switching easily between VM configurations seems interesting.
>>
>>I think that multiple VM's is a worthy goal as long as you can minimise CPU
>>usage. Having multiple VM's gives you the ability to do some very cool
>>things. I use VMWARE in Windows and sometimes have both Linux and FreeBSD
>>running in VM's so I can test software against all 3 OS's at once. I imagine
>>it would be very useful to developers of cluster software.
>>
>>I tried the Win32 port the other day, running Linux, and it sat using 100%
>>of the CPU whilst doing next to nothing at a command prompt. Using VMWARE,
>>and waiting at a command prompt uses very little CPU time.
>>
>>Is QEMU sat in a busy loop all the time?
>
>
> it is not QEMU but the hosted OS that is in the busy loop. QEMU
> will have to recognise "idle loops" to fix this - this could be
> really tricky.
I guess if QEMU emulates the hlt instruction and the OS supports it then it's pretty easy.
I note above it said running linux, which does idle nicely when the hlt instruction is present,
perhaps there is a not too difficult way for intelligent OS's. DOS is a lost cause however.
Brad
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Qemu workstation
2004-04-06 13:28 ` Brad Campbell
@ 2004-04-06 20:23 ` Filip Navara
2004-04-07 4:34 ` Brad Campbell
0 siblings, 1 reply; 26+ messages in thread
From: Filip Navara @ 2004-04-06 20:23 UTC (permalink / raw)
To: qemu-devel
Brad Campbell wrote:
> I guess if QEMU emulates the hlt instruction and the OS supports it
> then it's pretty easy.
> I note above it said running linux, which does idle nicely when the
> hlt instruction is present, perhaps there is a not too difficult way
> for intelligent OS's. DOS is a lost cause however.
To clarify it, it's not 'HLT' instruction (Halt processor), but the
'NOP' instruction (No operation).
- Filip
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Qemu workstation
2004-04-06 20:23 ` Filip Navara
@ 2004-04-07 4:34 ` Brad Campbell
2004-04-07 7:59 ` Filip Navara
0 siblings, 1 reply; 26+ messages in thread
From: Brad Campbell @ 2004-04-07 4:34 UTC (permalink / raw)
To: qemu-devel
Filip Navara wrote:
> Brad Campbell wrote:
>
>> I guess if QEMU emulates the hlt instruction and the OS supports it
>> then it's pretty easy.
>> I note above it said running linux, which does idle nicely when the
>> hlt instruction is present, perhaps there is a not too difficult way
>> for intelligent OS's. DOS is a lost cause however.
>
>
> To clarify it, it's not 'HLT' instruction (Halt processor), but the
> 'NOP' instruction (No operation).
How does that work then?
I have some code that uses a NOP loop for accurate timing? That spins at 100% cpu usage, how does a
NOP tell the processor to idle? HLT does.
Brad
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Qemu workstation
2004-04-07 4:34 ` Brad Campbell
@ 2004-04-07 7:59 ` Filip Navara
2004-04-07 8:24 ` Brad Campbell
0 siblings, 1 reply; 26+ messages in thread
From: Filip Navara @ 2004-04-07 7:59 UTC (permalink / raw)
To: qemu-devel
Brad Campbell wrote:
> How does that work then?
I don't know the exact details.
> I have some code that uses a NOP loop for accurate
> timing? That spins at 100% cpu usage, how does a
> NOP tell the processor to idle? HLT does.
HLT instruction halts the CPU so no more instructions are
processed and the CPU freezes. That's usable only in situation
like Windows blue screens.
- Filip
--
ANONYMNI PRIPOJENI K INTERNETU - bez registrace, zdarma, ihned!
Pripojeni na cisle 971 200 111 z cele CR,
v Praze navic na cisle 971 200 555.
Uzivatelske jmeno "volny", heslo "volny".
http://sluzby.volny.cz/product/dialup/anon/
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Qemu workstation
2004-04-07 7:59 ` Filip Navara
@ 2004-04-07 8:24 ` Brad Campbell
2004-04-07 8:47 ` Grzegorz Kulewski
2004-04-07 9:40 ` Filip Navara
0 siblings, 2 replies; 26+ messages in thread
From: Brad Campbell @ 2004-04-07 8:24 UTC (permalink / raw)
To: qemu-devel
Filip Navara wrote:
> Brad Campbell wrote:
>
>>How does that work then?
>
>
> I don't know the exact details.
>
>
>>I have some code that uses a NOP loop for accurate
>>timing? That spins at 100% cpu usage, how does a
>>NOP tell the processor to idle? HLT does.
>
>
> HLT instruction halts the CPU so no more instructions are
> processed and the CPU freezes. That's usable only in situation
> like Windows blue screens.
It does? My information tells me that it halts the processor until an interrupt or other wakeup
source occurs. Check arch/i386/kernel/process.c
/*
* We use this if we don't have any better
* idle routine..
*/
void default_idle(void)
{
if (current_cpu_data.hlt_works_ok && !hlt_counter) {
__cli();
if (!current->need_resched)
safe_halt();
else
__sti();
}
}
and in include/asm/system.h
system.h:#define safe_halt() __asm__ __volatile__("sti; hlt": : :"memory")
Looks like a hlt to me and not a nop in site.
The kernel does a check at boot time to see if the processor supports the hlt instruction and if it
does it uses that in the idle loop.
Am I wrong?
Brad
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Qemu workstation
2004-04-07 8:24 ` Brad Campbell
@ 2004-04-07 8:47 ` Grzegorz Kulewski
2004-04-07 17:50 ` Richard Zidlicky
2004-04-07 9:40 ` Filip Navara
1 sibling, 1 reply; 26+ messages in thread
From: Grzegorz Kulewski @ 2004-04-07 8:47 UTC (permalink / raw)
To: qemu-devel
On Wed, 7 Apr 2004, Brad Campbell wrote:
> Filip Navara wrote:
> > Brad Campbell wrote:
> >
> >>How does that work then?
> >
> >
> > I don't know the exact details.
> >
> >
> >>I have some code that uses a NOP loop for accurate
> >>timing? That spins at 100% cpu usage, how does a
> >>NOP tell the processor to idle? HLT does.
> >
> >
> > HLT instruction halts the CPU so no more instructions are
> > processed and the CPU freezes. That's usable only in situation
> > like Windows blue screens.
>
> It does? My information tells me that it halts the processor until an interrupt or other wakeup
> source occurs. Check arch/i386/kernel/process.c
>
> /*
> * We use this if we don't have any better
> * idle routine..
> */
> void default_idle(void)
> {
> if (current_cpu_data.hlt_works_ok && !hlt_counter) {
> __cli();
> if (!current->need_resched)
> safe_halt();
> else
> __sti();
> }
> }
>
> and in include/asm/system.h
>
> system.h:#define safe_halt() __asm__ __volatile__("sti; hlt": : :"memory")
>
> Looks like a hlt to me and not a nop in site.
> The kernel does a check at boot time to see if the processor supports the hlt instruction and if it
> does it uses that in the idle loop.
>
> Am I wrong?
You are right.
HLT will block only until interrupt arrives. And there is at least clock
interrupt from time to time.
It helps to cool down the processor too. And autodetection on some
processors / motherboards is not correct, so there is nohalt kernel
parameter.
For blue screens (for me red since I use some tweaker :-) - *no more blue
screens*(TM)) win probably uses JMP $ or something like that (depending on
their/your assembler syntax).
And NOP instruction is not good candidate for wasting time anymore on
newer processrs (since PII I think, maybe later) since processor can
optimize it out and the only thing that survives that optimization is
conditional jump, but in cache, so latency is very small.
regards
Grzegorz Kulewski
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Qemu workstation
2004-04-07 8:47 ` Grzegorz Kulewski
@ 2004-04-07 17:50 ` Richard Zidlicky
0 siblings, 0 replies; 26+ messages in thread
From: Richard Zidlicky @ 2004-04-07 17:50 UTC (permalink / raw)
To: qemu-devel
On Wed, Apr 07, 2004 at 10:47:26AM +0200, Grzegorz Kulewski wrote:
> On Wed, 7 Apr 2004, Brad Campbell wrote:
>
> > Filip Navara wrote:
> > > Brad Campbell wrote:
> > >
> > >>How does that work then?
> > >
> > >
> > > I don't know the exact details.
> > >
> > >
> > >>I have some code that uses a NOP loop for accurate
> > >>timing? That spins at 100% cpu usage, how does a
> > >>NOP tell the processor to idle? HLT does.
> > >
> > >
> > > HLT instruction halts the CPU so no more instructions are
> > > processed and the CPU freezes. That's usable only in situation
> > > like Windows blue screens.
> >
> > It does? My information tells me that it halts the processor until an interrupt or other wakeup
> > source occurs. Check arch/i386/kernel/process.c
> >
> > /*
> > * We use this if we don't have any better
> > * idle routine..
> > */
> > void default_idle(void)
> > {
> > if (current_cpu_data.hlt_works_ok && !hlt_counter) {
> > __cli();
> > if (!current->need_resched)
> > safe_halt();
> > else
> > __sti();
> > }
> > }
> >
> > and in include/asm/system.h
> >
> > system.h:#define safe_halt() __asm__ __volatile__("sti; hlt": : :"memory")
> >
> > Looks like a hlt to me and not a nop in site.
> > The kernel does a check at boot time to see if the processor supports the hlt instruction and if it
> > does it uses that in the idle loop.
> >
> > Am I wrong?
>
> You are right.
>
> HLT will block only until interrupt arrives. And there is at least clock
> interrupt from time to time.
.. anyone remembers the Pentium(tm) "halt" bug ? How should QEMU
emulate that ?;)
it is easy when the guest OS uses hlt of course but a brief look
at some Linux kernel sources suggests there are a few more methods
to do it. Well x86 assembly was never my strong point.
Richard
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Qemu workstation
2004-04-07 8:24 ` Brad Campbell
2004-04-07 8:47 ` Grzegorz Kulewski
@ 2004-04-07 9:40 ` Filip Navara
1 sibling, 0 replies; 26+ messages in thread
From: Filip Navara @ 2004-04-07 9:40 UTC (permalink / raw)
To: qemu-devel
----- PŮVODNÍ ZPRÁVA -----
Od: "Brad Campbell" <brad@wasp.net.au>
Komu: qemu-devel@nongnu.org
Předmět: Re: [Qemu-devel] Qemu workstation
Datum: 7.4.2004 - 10:24:12
...
> It does? My information tells me that it halts the
> processor until an interrupt or other wakeup
> source occurs. Check arch/i386/kernel/process.c
>
> /*
> * We use this if we don't have any better
> * idle routine..
> */
> void default_idle(void)
> {
> if (current_cpu_data.hlt_works_ok && !hlt_counter) {
> __cli();
> if (!current->need_resched)
> safe_halt();
> else
> __sti();
> }
> }
>
> and in include/asm/system.h
>
> system.h:#define safe_halt() __asm__
> __volatile__("sti; hlt": : :"memory")
>
> Looks like a hlt to me and not a nop in site.
> The kernel does a check at boot time to see if the
> processor supports the hlt instruction and if it
> does it uses that in the idle loop.
>
> Am I wrong?
>
> Brad
>
You are right and I'm wrong, sorry.
- Filip
--
ANONYMNI PRIPOJENI K INTERNETU - bez registrace, zdarma, ihned!
Pripojeni na cisle 971 200 111 z cele CR,
v Praze navic na cisle 971 200 555.
Uzivatelske jmeno "volny", heslo "volny".
http://sluzby.volny.cz/product/dialup/anon/
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Qemu workstation
2004-04-06 12:17 ` Richard Zidlicky
2004-04-06 13:28 ` Brad Campbell
@ 2004-04-06 14:00 ` Jamie Burns
1 sibling, 0 replies; 26+ messages in thread
From: Jamie Burns @ 2004-04-06 14:00 UTC (permalink / raw)
To: qemu-devel
Isnt there an instruction that gets sent when the OS is idle? To keep
processors cool etc?
VMWare describes some of this in:
http://www.vmware.com/support/kb/enduser/std_adp.php?p_faqid=1077
:o)
----- Original Message -----
From: "Richard Zidlicky" <rz@linux-m68k.org>
To: <qemu-devel@nongnu.org>
Sent: Tuesday, April 06, 2004 1:17 PM
Subject: Re: [Qemu-devel] Qemu workstation
> On Mon, Apr 05, 2004 at 10:49:51PM +0100, Jamie Burns wrote:
> > > I am not sure that handling multiple VMs running at the same time is
> > > very useful (some architectural changes are needed in QEMU). But
> > > switching easily between VM configurations seems interesting.
> >
> > I think that multiple VM's is a worthy goal as long as you can minimise
CPU
> > usage. Having multiple VM's gives you the ability to do some very cool
> > things. I use VMWARE in Windows and sometimes have both Linux and
FreeBSD
> > running in VM's so I can test software against all 3 OS's at once. I
imagine
> > it would be very useful to developers of cluster software.
> >
> > I tried the Win32 port the other day, running Linux, and it sat using
100%
> > of the CPU whilst doing next to nothing at a command prompt. Using
VMWARE,
> > and waiting at a command prompt uses very little CPU time.
> >
> > Is QEMU sat in a busy loop all the time?
>
> it is not QEMU but the hosted OS that is in the busy loop. QEMU
> will have to recognise "idle loops" to fix this - this could be
> really tricky.
>
> Richard
>
>
>
> _______________________________________________
> Qemu-devel mailing list
> Qemu-devel@nongnu.org
> http://mail.nongnu.org/mailman/listinfo/qemu-devel
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Qemu workstation
2004-04-05 21:49 ` Jamie Burns
2004-04-06 12:17 ` Richard Zidlicky
@ 2004-04-06 19:00 ` Fabrice Bellard
1 sibling, 0 replies; 26+ messages in thread
From: Fabrice Bellard @ 2004-04-06 19:00 UTC (permalink / raw)
To: qemu-devel
Jamie Burns wrote:
> Is QEMU sat in a busy loop all the time?
No. It comes from the Windows port. I'll make a simple patch soon.
Fabrice.
^ permalink raw reply [flat|nested] 26+ messages in thread
* Re: [Qemu-devel] Qemu workstation
2004-04-05 9:10 ` John R. Hogerhuis
2004-04-05 9:30 ` Rudi Lippert
@ 2004-04-05 9:38 ` Jean-Michel POURE
2004-04-05 10:23 ` John R. Hogerhuis
1 sibling, 1 reply; 26+ messages in thread
From: Jean-Michel POURE @ 2004-04-05 9:38 UTC (permalink / raw)
To: qemu-devel
Dear all,
> Sweet Jesus... a new name, vmware shell look alike (not a step in the
> right direction IMHO... we could probably come up with a better UI than
> to rehash vmware's...) and the win32 port is not really operational yet
> (unless 0.5.3 actually made it process .iso files... I haven't built
> yet...)
Unless further evidence, source-code of QEWS for Win32 is not made available.
> Well I guess there's something to be said for multi-tasking.
> Does anyone know who this is? I'd like to find out what kind of magic
> they are performing to get ReactOS running in win32 port.
> Alas I suspect GIMP at work...
Do you mean this project might be a hoax?
On the other hand, I would very like appreciate Alex (from the Morphix
project) to commit his GNU/Linux code to Qemu CVS. It would probably be
time/energy saving to build the GUI from Qemu CVS.
Cheers,
Jean-Michel
^ permalink raw reply [flat|nested] 26+ messages in thread
end of thread, other threads:[~2004-04-08 19:47 UTC | newest]
Thread overview: 26+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2004-04-05 15:19 [Qemu-devel] Qemu workstation Mike Nordell
2004-04-05 20:40 ` Filip Navara
2004-04-05 21:05 ` John R. Hogerhuis
2004-04-05 21:15 ` Filip Navara
2004-04-05 21:15 ` [Qemu-devel] " Martin Fuchs
2004-04-05 21:40 ` John R. Hogerhuis
2004-04-05 22:12 ` Filip Navara
-- strict thread matches above, loose matches on Subject: below --
2004-04-05 8:47 [Qemu-devel] " Jean-Michel POURE
2004-04-05 9:10 ` John R. Hogerhuis
2004-04-05 9:30 ` Rudi Lippert
2004-04-05 9:55 ` Jean-Michel POURE
2004-04-05 19:31 ` Fabrice Bellard
2004-04-05 21:49 ` Jamie Burns
2004-04-06 12:17 ` Richard Zidlicky
2004-04-06 13:28 ` Brad Campbell
2004-04-06 20:23 ` Filip Navara
2004-04-07 4:34 ` Brad Campbell
2004-04-07 7:59 ` Filip Navara
2004-04-07 8:24 ` Brad Campbell
2004-04-07 8:47 ` Grzegorz Kulewski
2004-04-07 17:50 ` Richard Zidlicky
2004-04-07 9:40 ` Filip Navara
2004-04-06 14:00 ` Jamie Burns
2004-04-06 19:00 ` Fabrice Bellard
2004-04-05 9:38 ` Jean-Michel POURE
2004-04-05 10:23 ` John R. Hogerhuis
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).