Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1753416AbeAKB10 (ORCPT <rfc822;ralf@linux-mips.org> + 1 other);
        Wed, 10 Jan 2018 20:27:26 -0500
Received: from szxga05-in.huawei.com ([45.249.212.191]:3768 "EHLO huawei.com"
        rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP
        id S1753304AbeAKB1Y (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
        Wed, 10 Jan 2018 20:27:24 -0500
Message-ID: <5A56BD66.8040607@huawei.com>
Date: Thu, 11 Jan 2018 09:27:02 +0800
From: Xishi Qiu <qiuxishi@huawei.com>
User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:12.0) Gecko/20120428 Thunderbird/12.0.1
MIME-Version: 1.0
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>
Subject: Re: [RFC] mm: why vfree() do not free page table memory?
References: <5A4603AB.8060809@huawei.com>
In-Reply-To: <5A4603AB.8060809@huawei.com>
Content-Type: text/plain; charset="ISO-8859-1"
Content-Transfer-Encoding: 7bit
X-Originating-IP: [10.177.25.179]
X-CFilter-Loop: Reflected
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org
Return-Path: <linux-kernel-owner@vger.kernel.org>

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

> 
> .
>