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Date: Tue, 18 Oct 2011 15:28:05 +0800
From: Chen Gong <gong.chen@linux.intel.com>
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To: Seiji Aguchi <seiji.aguchi@hds.com>
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Subject: Re: [RFC][PATCH -next] make pstore/kmsg_dump run after stopping other
 cpus in panic path
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于 2011/10/17 22:10, Seiji Aguchi 写道:
> Hi,
>
> Thank you for giving me a comment.
>
>> I have a stupid question: since you have serialized the process procedure via
>> smp_send_stop, why still using spin_lock_xxx? Maybe preempt_disable/enable is
>> enough?
>
>
> I added spin_lock_init() in panic path for sharing code with other triggers
> such as oops/reboot/emergency_restart because they still need spin_locks.
>
> Do you suggest following code?
>
> <snip>
> If(!panic)
> 	spin_lock_irqsave();
>
>       .
>       .
> If(!panic)
> 	spin_unlock_restore();
> <snip>
>
> I don't stick to current patch.
> So I will resend a patch above if you request.

Yes, it looks more readable.

+	if (reason == KMSG_DUMP_PANIC)
+		raw_spin_lock_init(&logbuf_lock);

above codes look a little bit confused