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From: malc <av1474@comtv.ru>
To: 陳韋任 <chenwj@iis.sinica.edu.tw>
Cc: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] Why we need unlink tb when cpu_interrupt/cpu_exit get called?
Date: Mon, 2 Apr 2012 13:15:11 +0400 (MSK)	[thread overview]
Message-ID: <alpine.LNX.2.00.1204021255300.9502@linmac> (raw)
In-Reply-To: <20120402034542.GA59901@cs.nctu.edu.tw>

On Mon, 2 Apr 2012, ??? wrote:

> Hi all,
> 
>   I am wondering why we need to unlink tb when cpu_interrupt/cpu_exit is
> called, and want to know what happened if we don't unlink tb. In theory,
> QEMU want the execution flow comes back from code cache to QEMU itself
> so that interrupts can be handled as soon as possible. However, I ran
> linux-0.2.img with a modified QEMU whose cpu_unlink_tb does nothing.
> Everything seems work fine. Is this experiment too trivial to show what
> bad things happened when we don't unlink tb?
> 
>   Thanks! :)

Try following with and without tb unlinking on aforementioned image to
feel the difference:

sh-2.05b# echo "char main[]={0xeb,-2};" >h.c
sh-2.05b# tcc -run h.c

-- 
mailto:av1474@comtv.ru

  reply	other threads:[~2012-04-02  9:15 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-04-02  3:45 [Qemu-devel] Why we need unlink tb when cpu_interrupt/cpu_exit get called? 陳韋任
2012-04-02  9:15 ` malc [this message]
2012-04-02 10:21   ` 陳韋任
2012-04-02 10:32     ` malc

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