linux-kernel - Re: [PATCH] KVM: don't sent IPI if the vcpu is not online

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Mon, 6 Sep 2010 11:19:16 +0200
From:	Alexander Graf <agraf@...e.de>
To:	Avi Kivity <avi@...hat.com>
Cc:	Xiao Guangrong <xiaoguangrong@...fujitsu.com>,
	Marcelo Tosatti <mtosatti@...hat.com>,
	LKML <linux-kernel@...r.kernel.org>, KVM <kvm@...r.kernel.org>
Subject: Re: [PATCH] KVM: don't sent IPI if the vcpu is not online


On 06.09.2010, at 11:14, Avi Kivity wrote:

> On 09/06/2010 12:09 PM, Alexander Graf wrote:
>> 
>>> It can also be running host kernel or user code.
>> In that case it's the same as running guest code, no? We'll pass by the vcpu entry check asap.
> 
> Sure, but the IPI is wasted.  If you spend 10% of your time in host code, you can avoid 10% of the IPIs.
> 
> (actually less, since the atomic part of the guest switch has guest_mode enabled)

Oh. My bad. I had a thinko here :).

Sure, sounds like a good idea.


Alex

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/