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Message-ID: <1375939750.18565.11.camel@marge.simpson.net>
Subject: Re: [PATCH V3]hrtimer: Fix a performance regression by disable
 reprogramming in remove_hrtimer
From: Mike Galbraith <bitbucket@online.de>
To: "ethan.zhao" <ethan.kernel@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>, johlstei@codeaurora.org,
        Yinghai Lu <yinghai@kernel.org>, Jin Feng <joe.jin@oracle.com>,
        Youquan Song <youquan.song@intel.com>, LenBrown <len.brown@intel.com>
Date: Thu, 08 Aug 2013 07:29:10 +0200
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(I got several copies of that, one would have been plenty.  Some people
get all grumpy when they get repeats, and at least one, who shall remain
unnamed, gets even grumpier when folks don't trim their replies, so be
careful;)

On Thu, 2013-08-08 at 12:31 +0800, ethan.zhao wrote:

> diff --git a/arch/x86/include/asm/smp.h b/arch/x86/include/asm/smp.h
> index 4137890..c27f04f 100644
> --- a/arch/x86/include/asm/smp.h
> +++ b/arch/x86/include/asm/smp.h
> @@ -137,7 +137,7 @@ static inline void play_dead(void)
> 
> static inline void smp_send_reschedule(int cpu)
> {
> -       smp_ops.smp_send_reschedule(cpu);
> +       /* smp_ops.smp_send_reschedule(cpu); */
> }

Hm.  You're much braver than I am.

-Mike