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Message-ID: <5A56BD66.8040607@huawei.com>
Date: Thu, 11 Jan 2018 09:27:02 +0800
From: Xishi Qiu <qiuxishi@huawei.com>
MIME-Version: 1.0
Subject: Re: [RFC] mm: why vfree() do not free page table memory?
References: <5A4603AB.8060809@huawei.com>
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To: Xishi Qiu <qiuxishi@huawei.com>
Cc: Michal Hocko <mhocko@kernel.org>, Vlastimil Babka <vbabka@suse.cz>, Mel
 Gorman <mgorman@techsingularity.net>, LKML <linux-kernel@vger.kernel.org>, Linux MM <linux-mm@kvack.org>, "Wujiangtao (A)" <wu.wujiangtao@huawei.com>, "Qiuchangqi (Lion, Euler Dept )" <qiuchangqi.qiu@huawei.com>

On 2017/12/29 16:58, Xishi Qiu wrote:

> When calling vfree(), it calls unmap_vmap_area() to clear page table,
> but do not free the memory of page table, why? just for performance?
> 
> If a driver use vmalloc() and vfree() frequently, we will lost much
> page table memory, maybe oom later.
> 
> Thanks,
> Xishi Qiu
> 

ping

> 
> .
> 



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