Re: MONITOR and MWAIT Instruction Emulation in BOCHS

"Stanislav" <[email protected]>
Newsgroups gmane.comp.emulators.bochs.devel
Message-ID <[email protected]>
In real life (and I tried to make the Bochs similarly) MWAIT means the same
as HLT. The CPU stops running instructions and going into a HLT (sleep)
state.

 

In emulation I would expect to stop running thread executing MWAIT
completely and resume it only when monitored write happens (or another
wakeup event).

 

Stanislav

 

From: Xin Tong [mailto:[email protected]] 
Sent: Sunday, October 21, 2012 5:26 PM
To: [email protected]
Subject: Re: [Bochs-developers] MONITOR and MWAIT Instruction Emulation in
BOCHS

 

one other thing is that in modern OS and applications Monitor & Mwait are
used to reduce power on the processors. on a overcommited system ( i.e.
emulating 16 cores on a machine with only 4 cores). this sequence should be
able to use as a hint to schedule the virtual core intelligently. can anyone
familiar with this comment on this ?

 

Xin 

 

On Sun, Oct 21, 2012 at 10:36 AM, Xin Tong <[email protected]>
wrote:

I am looking at how MONITOR  and MWAIT  are emulated in BOCHS. one thing i
do not get is why bx_pc_system.invlpg(paddr) is called when Mointor paddr is
called. bx_pc_system.invlpg(paddr) calls TLB_invlpg on all CPUs. I do not
why TLB_invlpg is called as there is no invalidation going on in the Monitor
instruction.

Xin

------------------------------------------------------------------------------
Everyone hates slow websites. So do we.
Make your web apps faster with AppDynamics
Download AppDynamics Lite for free today:
http://p.sf.net/sfu/appdyn_sfd2d_oct

_______________________________________________
bochs-developers mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/bochs-developers
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.