Back to UTCB IPC
adam at os.inf.tu-dresden.de
Sun Oct 11 19:58:36 CEST 2009
On Sat Oct 10, 2009 at 10:51:02 +0800, Guanghui, Cheng wrote:
> I pushed this old mail to top and i want to know something about UTCB IPC.
> > > UTCB values stays the same. It depends on the generated stub whether
> > > UTCB IPC is actually used or not. Sending a flexpage, usually
> > > disqualifies the usage of UTCB IPC.
> > Do you mean, once a flexpage is sent no UTCB IPC should be sent after ?
> I am interested in the question above because in the Thread::transfer_msg
> function as this:
> 1343 sender_regs->copy_msg (dst_regs);
> 1345 copy_utcb_to (tag, receiver);
> It seems every time the utcb ipc will follow the register ipc. Is it right?
Yes, actually there's no difference.
Adam adam at os.inf.tu-dresden.de
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