Message-ID: <4FEB5A7E.8040500@linux.vnet.ibm.com>
Date: Wed, 27 Jun 2012 14:09:50 -0500
From: Seth Jennings <sjenning@linux.vnet.ibm.com>
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To: Minchan Kim <minchan@kernel.org>
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        devel@driverdev.osuosl.org,
        Dan Magenheimer <dan.magenheimer@oracle.com>,
        Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        Andrew Morton <akpm@linux-foundation.org>,
        Robert Jennings <rcj@linux.vnet.ibm.com>,
        Nitin Gupta <ngupta@vflare.org>
Subject: Re: [PATCH 2/3] zsmalloc: add generic path and remove x86 dependency
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On 06/27/2012 12:28 AM, Minchan Kim wrote:
>> +{
>> +	if (area->vm)
>> +		return 0;
> 
> 
> Just out of curiosity.
> When do we need above check?

I did this in the case that there was a race between the for
loop in zs_init(), calling zs_cpu_notifier(), and a CPU
coming online.  I've never seen the condition hit, but if it
did, it would leak memory without this check.

I would move the cpu notifier registration after the loop in
zs_init(), but then I could miss a cpu up event and we
wouldn't have the needed per-cpu resources for mapping.

All other suggestions are accepted.  Thanks for the feedback!

--
Seth

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