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Date: Wed, 30 Nov 2011 08:44:24 +0800
From: Wu Fengguang <fengguang.wu@intel.com>
To: Jan Kara <jack@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>,
        Andi Kleen <andi@firstfloor.org>, Ingo Molnar <mingo@elte.hu>,
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Subject: Re: [PATCH 6/9] readahead: add /debug/readahead/stats
Message-ID: <20111130004424.GC11147@localhost>
References: <20111129130900.628549879@intel.com>
 <20111129131456.666312513@intel.com>
 <20111129152106.GN5635@quack.suse.cz>
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>   This looks all inherently racy (which doesn't matter much as you suggest)
> so I just wanted to suggest that if you used per-cpu counters you'd get
> race-free and faster code at the cost of larger data structures and using
> percpu_counter_add() instead of ++ (which doesn't seem like a big
> complication to me).

No problem. I'll switch to per-cpu counters in next post.

Thanks,
Fengguang