From mboxrd@z Thu Jan  1 00:00:00 1970
From: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Subject: Re: [PATCH 1/4] KVM: MMU: support disable/enable mmu audit dynamicly
Date: Mon, 30 Aug 2010 09:58:27 +0800
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Cc: Marcelo Tosatti <mtosatti@redhat.com>,
	LKML <linux-kernel@vger.kernel.org>, KVM <kvm@vger.kernel.org>
To: Avi Kivity <avi@redhat.com>
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On 08/29/2010 05:16 PM, Avi Kivity wrote:
>  On 08/28/2010 03:00 PM, Xiao Guangrong wrote:
>> Add the debugfs file named 'mmu-debug', we can disable/enable mmu
>> audit by
>> this file:
>>
>> enable:
>> echo 1>  debugfs/kvm/mmu-debug
>>
>> disable:
>> echo 0>  debugfs/kvm/mmu-debug
> 
> 
> Better as a runtime rw module parameter perhaps?  At least it avoids the
> large debugfs callbacks.
> 

Yeah, it's a good idea.

> Also, call it audit to preserve the name.

OK

>> +
>> +TRACE_EVENT(
>> +    kvm_mmu_audit,
>> +    TP_PROTO(struct kvm_vcpu *vcpu, const char *msg),
>> +    TP_ARGS(vcpu, msg),
>> +
>> +    TP_STRUCT__entry(
>> +        __field(struct kvm_vcpu *, vcpu)
>> +        __field(const char *, msg)
>> +    ),
> 
> enum instead of char *, maybe something in userspace can make use of this.
> 

OK

>> +
>> +    TP_fast_assign(
>> +        __entry->vcpu = vcpu;
>> +        __entry->msg = msg;
>> +    ),
>> +
>> +    TP_printk("%s", __entry->msg)
> 
> Here, of course, you can use print_symbolic() to preserve readability.

OK

Will fix them in the next version.