From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rik van Riel <riel@redhat.com>
Subject: Re: [RFC -v7 PATCH 4/7] Add yield_to(task, preempt) functionality.
Date: Mon, 31 Jan 2011 13:11:35 -0500
Message-ID: <4D46FB57.2080005@redhat.com>
References: <20110126165657.2ddd2ac9@annuminas.surriel.com>	 <20110126172148.32d07561@annuminas.surriel.com> <1296474542.15234.394.camel@laptop>
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Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
	Avi Kiviti <avi@redhat.com>,
	Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>,
	Mike Galbraith <efault@gmx.de>,
	Chris Wright <chrisw@sous-sol.org>, ttracy@redhat.com,
	"Nakajima, Jun" <jun.nakajima@intel.com>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
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On 01/31/2011 06:49 AM, Peter Zijlstra wrote:
> On Wed, 2011-01-26 at 17:21 -0500, Rik van Riel wrote:

>> +       if (yielded)
>> +               yield();
>> +
>> +       return yielded;
>> +}
>> +EXPORT_SYMBOL_GPL(yield_to);
>
> yield() will again acquire rq->lock.. not not simply have
> ->yield_to_task() do everything required and make that an unconditional
> schedule()?

I wanted to reduce code duplication, since this code path
should not be taken all that frequently.  But hey, you're
the maintainer, so I'll implement it your way :)

The patches should be on the way later today :)

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