Date: Wed, 15 Feb 2012 09:39:58 +0800
From: Yong Zhang <yong.zhang0@gmail.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Venki Pallipadi <venki@google.com>, Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
        Suresh Siddha <suresh.b.siddha@intel.com>,
        Aaron Durbin <adurbin@google.com>, Paul Turner <pjt@google.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [RFC] Extend mwait idle to optimize away IPIs when possible
Message-ID: <20120215013958.GA24229@zhy>
Reply-To: Yong Zhang <yong.zhang0@gmail.com>
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On Tue, Feb 14, 2012 at 02:52:17PM +0100, Peter Zijlstra wrote:
> On Mon, 2012-02-13 at 13:34 +0800, Yong Zhang wrote:
> > Yeah, most of the things could be shared. Such as the added logic when
> > return from idle and the hooks into ttwu_queue_remote() and
> > generic_exec_single().
> > 
> 
> The thing is, those last two should not have hooks. 

Yeah, it's general place; and smp_need_ipi() plays well.

> Nor am I convinced
> anything outside of the arch idle loop should have any.

'idle loop' is the key point :)

Thanks,
Yong
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