From: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
To: Rik van Riel <riel@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>,
kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
Avi Kiviti <avi@redhat.com>,
Peter Zijlstra <a.p.zijlstra@chello.nl>,
Ingo Molnar <mingo@elte.hu>,
Anthony Liguori <aliguori@linux.vnet.ibm.com>
Subject: Re: [RFC PATCH 2/3] sched: add yield_to function
Date: Fri, 3 Dec 2010 22:59:54 +0530 [thread overview]
Message-ID: <20101203172954.GC11725@linux.vnet.ibm.com> (raw)
In-Reply-To: <4CF9242D.4090007@redhat.com>
On Fri, Dec 03, 2010 at 12:09:01PM -0500, Rik van Riel wrote:
> I don't see how that is going to help get the lock
> released, when the VCPU holding the lock is on another
> CPU.
Even the directed yield() is not guaranteed to get the lock released, given its
shooting in the dark?
Anyway, the intention of yield() proposed was not to get lock released
immediately (which will happen eventually), but rather to avoid inefficiency
associated with (long) spinning and at the same time make sure we are not
leaking our bandwidth to other guests because of a naive yield ..
- vatsa
next prev parent reply other threads:[~2010-12-03 17:30 UTC|newest]
Thread overview: 60+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-12-02 19:41 [RFC PATCH 0/3] directed yield for Pause Loop Exiting Rik van Riel
2010-12-02 19:43 ` [RFC PATCH 1/3] kvm: keep track of which task is running a KVM vcpu Rik van Riel
2010-12-03 1:18 ` Chris Wright
2010-12-03 14:50 ` Rik van Riel
2010-12-03 15:55 ` Chris Wright
2010-12-05 12:40 ` Avi Kivity
2010-12-03 12:17 ` Srivatsa Vaddagiri
2010-12-03 14:16 ` Rik van Riel
2010-12-05 12:59 ` Avi Kivity
2010-12-02 19:44 ` [RFC PATCH 2/3] sched: add yield_to function Rik van Riel
2010-12-03 0:50 ` Chris Wright
2010-12-03 18:27 ` Rik van Riel
2010-12-03 19:30 ` Chris Wright
2010-12-03 21:30 ` Peter Zijlstra
2010-12-03 5:54 ` Mike Galbraith
2010-12-03 13:46 ` Srivatsa Vaddagiri
2010-12-03 14:45 ` Mike Galbraith
2010-12-03 14:48 ` Rik van Riel
2010-12-03 15:09 ` Mike Galbraith
2010-12-03 15:35 ` Rik van Riel
2010-12-03 16:20 ` Srivatsa Vaddagiri
2010-12-03 17:09 ` Rik van Riel
2010-12-03 17:29 ` Srivatsa Vaddagiri [this message]
2010-12-03 17:33 ` Rik van Riel
2010-12-03 17:45 ` Srivatsa Vaddagiri
2010-12-03 20:05 ` Mike Galbraith
2010-12-03 21:26 ` Peter Zijlstra
2010-12-03 13:23 ` Peter Zijlstra
2010-12-03 13:30 ` Srivatsa Vaddagiri
2010-12-03 14:03 ` Peter Zijlstra
2010-12-03 14:06 ` Srivatsa Vaddagiri
2010-12-03 14:10 ` Srivatsa Vaddagiri
2010-12-03 21:23 ` Peter Zijlstra
2010-12-04 13:02 ` Rik van Riel
2010-12-10 4:34 ` Rik van Riel
2010-12-10 8:39 ` Srivatsa Vaddagiri
2010-12-10 14:55 ` Rik van Riel
2010-12-08 17:55 ` Rik van Riel
2010-12-08 20:00 ` Peter Zijlstra
2010-12-08 20:04 ` Peter Zijlstra
2010-12-08 22:59 ` Rik van Riel
2010-12-02 19:45 ` [RFC PATCH 3/3] kvm: use yield_to instead of sleep in kvm_vcpu_on_spin Rik van Riel
2010-12-03 2:24 ` Chris Wright
2010-12-05 12:58 ` Avi Kivity
2010-12-05 12:56 ` Avi Kivity
2010-12-08 22:38 ` Rik van Riel
2010-12-09 10:28 ` Avi Kivity
2010-12-09 17:07 ` Rik van Riel
2010-12-11 7:27 ` Avi Kivity
2010-12-02 22:41 ` [RFC PATCH 0/3] directed yield for Pause Loop Exiting Chris Wright
2010-12-05 13:02 ` Avi Kivity
2010-12-10 5:03 ` Balbir Singh
2010-12-10 14:54 ` Rik van Riel
2010-12-11 7:31 ` Avi Kivity
2010-12-11 13:57 ` Balbir Singh
2010-12-13 11:57 ` Avi Kivity
2010-12-13 12:39 ` Balbir Singh
2010-12-13 12:42 ` Avi Kivity
2010-12-13 17:02 ` Rik van Riel
2010-12-14 9:25 ` Balbir Singh
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