From: Avi Kivity <avi@redhat.com>
To: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>,
Thomas Gleixner <tglx@linutronix.de>,
Marcelo Tosatti <mtosatti@redhat.com>,
Ingo Molnar <mingo@redhat.com>, Rik van Riel <riel@redhat.com>,
Srikar <srikar@linux.vnet.ibm.com>,
S390 <linux-s390@vger.kernel.org>,
Carsten Otte <cotte@de.ibm.com>,
Christian Borntraeger <borntraeger@de.ibm.com>,
KVM <kvm@vger.kernel.org>, chegu vinod <chegu_vinod@hp.com>,
"Andrew M. Theurer" <habanero@linux.vnet.ibm.com>,
LKML <linux-kernel@vger.kernel.org>, X86 <x86@kernel.org>,
Gleb Natapov <gleb@redhat.com>,
linux390@de.ibm.com,
Srivatsa Vaddagiri <srivatsa.vaddagiri@gmail.com>,
Joerg Roedel <joerg.roedel@amd.com>
Subject: Re: [PATCH RFC V5 0/3] kvm: Improving directed yield in PLE handler
Date: Mon, 23 Jul 2012 13:03:14 +0300 [thread overview]
Message-ID: <500D2162.8010209@redhat.com> (raw)
In-Reply-To: <20120718133717.5321.71347.sendpatchset@codeblue.in.ibm.com>
On 07/18/2012 04:37 PM, Raghavendra K T wrote:
> Currently Pause Loop Exit (PLE) handler is doing directed yield to a
> random vcpu on pl-exit. We already have filtering while choosing
> the candidate to yield_to. This change adds more checks while choosing
> a candidate to yield_to.
>
> On a large vcpu guests, there is a high probability of
> yielding to the same vcpu who had recently done a pause-loop exit.
> Such a yield can lead to the vcpu spinning again.
>
> The patchset keeps track of the pause loop exit and gives chance to a
> vcpu which has:
>
> (a) Not done pause loop exit at all (probably he is preempted lock-holder)
>
> (b) vcpu skipped in last iteration because it did pause loop exit, and
> probably has become eligible now (next eligible lock holder)
>
> This concept also helps in cpu relax interception cases which use same handler.
>
Thanks, applied to 'queue'.
--
error compiling committee.c: too many arguments to function
next prev parent reply other threads:[~2012-07-23 10:03 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-18 13:37 [PATCH RFC V5 0/3] kvm: Improving directed yield in PLE handler Raghavendra K T
2012-07-18 13:37 ` [PATCH RFC V5 1/3] kvm/config: Add config to support ple or cpu relax optimzation Raghavendra K T
2012-07-18 13:37 ` [PATCH RFC V5 2/3] kvm: Note down when cpu relax intercepted or pause loop exited Raghavendra K T
2012-07-18 13:38 ` [PATCH RFC V5 3/3] kvm: Choose better candidate for directed yield Raghavendra K T
2012-07-18 14:39 ` Raghavendra K T
2012-07-19 9:47 ` [RESEND PATCH " Raghavendra K T
2012-07-20 17:36 ` [PATCH RFC V5 0/3] kvm: Improving directed yield in PLE handler Marcelo Tosatti
2012-07-22 12:34 ` Raghavendra K T
2012-07-22 12:43 ` Avi Kivity
2012-07-23 7:35 ` Christian Borntraeger
2012-07-22 17:58 ` Rik van Riel
2012-07-23 10:03 ` Avi Kivity [this message]
2012-09-07 13:11 ` [RFC][PATCH] Improving directed yield scalability for " Andrew Theurer
2012-09-07 18:06 ` Raghavendra K T
2012-09-07 19:42 ` Andrew Theurer
2012-09-08 8:43 ` Srikar Dronamraju
2012-09-10 13:16 ` Andrew Theurer
2012-09-10 16:03 ` Peter Zijlstra
2012-09-10 16:56 ` Srikar Dronamraju
2012-09-10 17:12 ` Peter Zijlstra
2012-09-10 19:10 ` Raghavendra K T
2012-09-10 20:12 ` Andrew Theurer
2012-09-10 20:19 ` Peter Zijlstra
2012-09-10 20:31 ` Rik van Riel
2012-09-11 6:08 ` Raghavendra K T
2012-09-11 12:48 ` Andrew Theurer
2012-09-11 18:27 ` Andrew Theurer
2012-09-13 11:48 ` Raghavendra K T
2012-09-13 21:30 ` Andrew Theurer
2012-09-14 17:10 ` Andrew Jones
2012-09-15 16:08 ` Raghavendra K T
2012-09-17 13:48 ` Andrew Jones
2012-09-14 20:34 ` Konrad Rzeszutek Wilk
2012-09-17 8:02 ` Andrew Jones
2012-09-16 8:55 ` Avi Kivity
2012-09-17 8:10 ` Andrew Jones
2012-09-18 3:03 ` Andrew Theurer
2012-09-19 13:39 ` Avi Kivity
2012-09-13 12:13 ` Avi Kivity
2012-09-11 7:04 ` Srikar Dronamraju
2012-09-10 14:43 ` Raghavendra K T
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