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Subject: Re: [RFC][PATCH][kprobe] enabling booster on the preemptible 	kernel, take 2
From: Ingo Molnar <mingo@redhat.com>
To: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: "bibo,mao" <bibo_mao@linux.intel.com>, "bibo,mao" <bibo.mao@intel.com>,         "Keshavamurthy, Anil S" <anil.s.keshavamurthy@intel.com>,         Ananth N Mavinakayanahalli <ananth@in.ibm.com>,         Prasanna S Panchamukhi <prasanna@in.ibm.com>,         SystemTAP <systemtap@sources.redhat.com>,         Satoshi Oshima <soshima@redhat.com>, Hideo Aoki <haoki@redhat.com>,         Yumiko Sugita <yumiko.sugita.yf@hitachi.com>
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Date: Tue, 31 Oct 2006 13:49:00 -0000
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On Tue, 2006-10-31 at 22:17 +0900, Masami Hiramatsu wrote:
> OK, I see.
> It seems problematic because the softirqd is PF_NOFREEZE and it
> can execute most of functions...
> I think we need to find a new way to solve this problem.

could you outline the problem to me? freeze_processes() should be a
generic facility to move all kernel processing into a 'known' context of
execution. All the PF_NOFREEZE kernel threads are supposed to do
periodic calls to try_to_freeze(). They should not (and most of the time
they do not) prevent freezing of all state on the system.

am i misunderstanding the problem?

	Ingo