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Subject: Re: [PATCH 2/3] mm: Handle numa statistics distinctively based-on
 different VM stats modes
To: Michal Hocko <mhocko@kernel.org>
Cc: "Luis R . Rodriguez" <mcgrof@kernel.org>,
        Kees Cook <keescook@chromium.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Jonathan Corbet <corbet@lwn.net>,
        Mel Gorman <mgorman@techsingularity.net>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Christopher Lameter <cl@linux.com>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        Vlastimil Babka <vbabka@suse.cz>, kemi <kemi.wang@intel.com>,
        Dave <dave.hansen@linux.intel.com>, Tim Chen <tim.c.chen@intel.com>,
        Andi Kleen <andi.kleen@intel.com>,
        Jesper Dangaard Brouer <brouer@redhat.com>,
        Ying Huang <ying.huang@intel.com>, Aaron Lu <aaron.lu@intel.com>,
        Proc sysctl <linux-fsdevel@vger.kernel.org>,
        Linux MM <linux-mm@kvack.org>,
        Linux Kernel <linux-kernel@vger.kernel.org>
References: <1505467406-9945-1-git-send-email-kemi.wang@intel.com>
 <1505467406-9945-3-git-send-email-kemi.wang@intel.com>
 <20170915115049.vqthfawg3y4r6ogh@dhcp22.suse.cz>
From: kemi <kemi.wang@intel.com>
Message-ID: <26bd25c8-294f-d3cc-8ba2-845a6da33fe5@intel.com>
Date: Mon, 18 Sep 2017 11:07:20 +0800
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On 2017年09月15日 19:50, Michal Hocko wrote:
> On Fri 15-09-17 17:23:25, Kemi Wang wrote:
> [...]
>> @@ -2743,6 +2745,17 @@ static inline void zone_statistics(struct zone *preferred_zone, struct zone *z)
>>  #ifdef CONFIG_NUMA
>>  	enum numa_stat_item local_stat = NUMA_LOCAL;
>>  
>> +	/*
>> +	 * skip zone_statistics() if vmstat is a coarse mode or zone statistics
>> +	 * is inactive in auto vmstat mode
>> +	 */
>> +
>> +	if (vmstat_mode) {
>> +		if (vmstat_mode == VMSTAT_COARSE_MODE)
>> +			return;
>> +	} else if (disable_zone_statistics)
>> +		return;
>> +
>>  	if (z->node != numa_node_id())
>>  		local_stat = NUMA_OTHER;
> 
> A jump label could make this completely out of the way for the case
> where every single cycle matters.
> 

Could you be more explicit for how to implement it here. Thanks very much.