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Date: Thu, 27 Oct 2011 00:38:13 +0530
From: Raghavendra K T <raghukt@linux.vnet.ibm.com>
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To: Avi Kivity <avi@redhat.com>
CC: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>,
        Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>,
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        Suzuki Poulose <suzuki@linux.vnet.ibm.com>,
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Subject: Re: [PATCH RFC V2 3/5] kvm hypervisor : Add two hypercalls to support
 pv-ticketlock
References: <20111023190307.16364.35381.sendpatchset@oc5400248562.ibm.com> <20111023190558.16364.2136.sendpatchset@oc5400248562.ibm.com> <4EA53A7D.300@redhat.com> <20111024122734.GA10634@linux.vnet.ibm.com> <4EA56385.9040302@redhat.com> <20111024135032.GB10634@linux.vnet.ibm.com> <4EA6FEC2.1060209@linux.vnet.ibm.com> <4EA7E21B.8020805@redhat.com>
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On 10/26/2011 04:04 PM, Avi Kivity wrote:
> On 10/25/2011 08:24 PM, Raghavendra K T wrote:
CCing Ryan also
>>
>> So then do also you foresee the need for directed yield at some point,
>> to address LHP? provided we have good improvements to prove.
>
> Doesn't this patchset completely eliminate lock holder preemption?
>
Basically I was curious whether we can do more better with your directed 
yield discussions in https://lkml.org/lkml/2010/8/2/106 .

I felt we can get little more improvement with doing directed yield to
lock-holder in case of LHP than sleeping. But I may be wrong.

So wanted to get the feedback, on whether I am thinking in right
direction.