From mboxrd@z Thu Jan  1 00:00:00 1970
From: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Subject: Re: [PATCH v6] kvm: make vcpu life cycle separated from kvm instance
Date: Wed, 28 Dec 2011 19:29:29 +0900
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Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, avi@redhat.com,
	aliguori@us.ibm.com, gleb@redhat.com, mtosatti@redhat.com,
	xiaoguangrong.eric@gmail.com, jan.kiszka@web.de,
	Takuya Yoshikawa <takuya.yoshikawa@gmail.com>
To: Liu ping fan <kernelfans@gmail.com>
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(2011/12/28 15:54), Liu ping fan wrote:

>> You are introducing kvm_arch_vcpu_zap().
>>
>> Then, apart from the "zap" naming issue I mentioned last time,
> Yes, I will correct "zap", as you said, its meaning is quite differen=
t
> from destroy. :-)
>
>> what about other architectures than x86?
>>
> Have not considered it in detail yet. At first step, I just want to
> figure out the whole frame, then, I will push them on other arch.
> Maybe you foresee some problem when extending this onto other arch,
> please tell me, thanks =EF=BC=9A-).

I do not mind if those are supported or not now.

But if not, you should write what is currently supported and what shoul=
d
be done in the future.

Of course, you should at least make sure that other architectures will
not be broken by your patch.

>>
>>> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
>>> index 900c763..b88d418d 100644
>>> --- a/include/linux/kvm_host.h
>>> +++ b/include/linux/kvm_host.h
>>> @@ -117,6 +117,7 @@ enum {
>>>
>>>    struct kvm_vcpu {
>>>        struct kvm *kvm;
>>> +     struct list_head list;
>>>    #ifdef CONFIG_PREEMPT_NOTIFIERS
>>>        struct preempt_notifier preempt_notifier;
>>>    #endif
>>> @@ -251,12 +252,14 @@ struct kvm {
>>>        struct mm_struct *mm; /* userspace tied to this vm */
>>>        struct kvm_memslots *memslots;
>>>        struct srcu_struct srcu;
>>> +     struct srcu_struct srcu_vcpus;
>>> +
>>
>> Another srcu.  This alone is worth explaining in the changelog IMO.
>>
> Sorry, but why? I think it is just a srcu, and because it has
> different aim and want a independent grace period, so not multiplex
> kvm->srcu.

I cannot say what MUST be explained in the changelog.
But many well known maintainers are telling the importance of changelog=
=2E

It is up to you, and KVM maintainers.

	Takuya