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Date: Wed, 27 May 2015 14:41:59 +0530
From: Viresh Kumar <viresh.kumar@linaro.org>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Paul McKenney <paulmck@linux.vnet.ibm.com>,
        Frederic Weisbecker <fweisbec@gmail.com>,
        Eric Dumazet <edumazet@google.com>,
        John Stultz <john.stultz@linaro.org>,
        Joonwoo Park <joonwoop@codeaurora.org>,
        Wenbo Wang <wenbo.wang@memblaze.com>
Subject: Re: [patch 2/7] timer: Remove FIFO guarantee
Message-ID: <20150527091159.GA2256@linux>
References: <20150526210723.245729529@linutronix.de>
 <20150526224511.757520403@linutronix.de>
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On 26-05-15, 22:50, Thomas Gleixner wrote:
> The FIFO guarantee has been violated by the introduction of timer
> slack already. Remove it.
> 
> This is a preparatory patch for converting the timer wheel to hlist
> which reduces the memory foot print of the wheel by 50%. It's a
> seperate patch so any (unlikely to happen) regression caused by this
> can be identified clearly.
> 
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> ---
>  kernel/time/timer.c |    6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
> 
> Index: tip/kernel/time/timer.c
> ===================================================================
> --- tip.orig/kernel/time/timer.c
> +++ tip/kernel/time/timer.c
> @@ -403,10 +403,8 @@ __internal_add_timer(struct tvec_base *b
>  		i = (expires >> (TVR_BITS + 3 * TVN_BITS)) & TVN_MASK;
>  		vec = base->tv5.vec + i;
>  	}
> -	/*
> -	 * Timers are FIFO:
> -	 */
> -	list_add_tail(&timer->entry, vec);
> +
> +	list_add(&timer->entry, vec);
>  }

Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>

-- 
viresh