From: Christian Borntraeger <borntraeger@de.ibm.com>
To: Paolo Bonzini <pbonzini@redhat.com>,
Wanpeng Li <kernellwp@gmail.com>,
linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: "Wanpeng Li" <wanpeng.li@hotmail.com>,
"Radim Krčmář" <rkrcmar@redhat.com>,
"David Matlack" <dmatlack@google.com>
Subject: Re: [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will fire soon
Date: Thu, 19 May 2016 17:03:37 +0200 [thread overview]
Message-ID: <573DD5C9.2000108@de.ibm.com> (raw)
In-Reply-To: <d7657003-0321-2e4d-6a55-bc7a70e85aca@redhat.com>
On 05/19/2016 04:56 PM, Paolo Bonzini wrote:
>
>
> On 19/05/2016 16:52, Christian Borntraeger wrote:
>>>> Would this work too and be simpler?
>> Hmm, your patch does only fiddle with the grow/shrink logic (which might
>> be a good idea independently of this change), but the original patch
>> actually takes into account that we have a guaranteed maximum time by a
>> wakeup timer - IOW we know exactly what the maximum poll time is.
>>
>
> Yes, it's different. The question is whether a 10us poll (40,000 clock
> cycles) has an impact even if it's sometimes wrong.
Valid question. As I said, this change might be something good independent from
the original patch. (it might make it unnecessary, though) On the other hand
I can handle ~30 guest entry/exit cycles of a simple exit like diag9c.
Needs measurement.
next prev parent reply other threads:[~2016-05-19 15:03 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-05-19 13:27 [PATCH v2] KVM: halt-polling: poll if emulated lapic timer will fire soon Wanpeng Li
2016-05-19 13:46 ` Christian Borntraeger
2016-05-19 13:57 ` Paolo Bonzini
2016-05-19 14:52 ` Christian Borntraeger
2016-05-19 14:56 ` Paolo Bonzini
2016-05-19 15:03 ` Christian Borntraeger [this message]
2016-05-19 15:06 ` Paolo Bonzini
2016-05-19 15:42 ` Christian Borntraeger
2016-05-24 2:48 ` Wanpeng Li
2016-05-19 18:01 ` David Matlack
2016-05-19 18:36 ` David Matlack
2016-05-20 2:04 ` Yang Zhang
2016-05-20 5:53 ` Wanpeng Li
2016-05-20 18:37 ` David Matlack
2016-05-23 1:26 ` Yang Zhang
2016-05-23 18:04 ` David Matlack
2016-05-24 1:13 ` Yang Zhang
2016-05-24 1:16 ` David Matlack
2016-05-24 2:55 ` Yang Zhang
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