Path: csiph.com!goblin3!goblin1!goblin.stu.neva.ru!news.panservice.it!bofh.it!news.nic.it!robomod From: Tang Chen Newsgroups: linux.kernel Subject: Re: [RFC] mm: direct mapping count in /proc/meminfo is error Date: Fri, 20 Nov 2015 09:50:03 +0100 Message-ID: References: X-Original-To: Xishi Qiu , Andrew Morton , zhong jiang , Minchan Kim , Mel Gorman X-Ironport-Av: E=Sophos;i="5.20,242,1444665600"; d="scan'208";a="666678" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.1.0 MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit Sender: robomod@news.nic.it List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Approved: robomod@news.nic.it Lines: 64 Organization: linux.* mail to news gateway X-Original-Cc: Linux MM , LKML X-Original-Date: Fri, 20 Nov 2015 16:43:43 +0800 X-Original-Message-ID: <564EDD3F.6070302@cn.fujitsu.com> X-Original-References: <564ED708.5090405@huawei.com> X-Original-Sender: linux-kernel-owner@vger.kernel.org Xref: csiph.com linux.kernel:1273856 Hi Shi, Would you please share where did you add the printk debug info ? Thanks. :) On 11/20/2015 04:17 PM, Xishi Qiu wrote: > I find the direct mapping count in /proc/meminfo is error. > The value should be equal to the size of init_memory_mapping which > showed in boot log. > > I add some print to show direct_pages_count[] immediately after > init_memory_mapping(). The reason is that we double counting. > > Here is the log(kernel v4.4): > ... > [ 0.000000] init_memory_mapping: [mem 0x00000000-0x000fffff] // called from "init_memory_mapping(0, ISA_END_ADDRESS);" > [ 0.000000] [mem 0x00000000-0x000fffff] page 4k > [ 0.000000] BRK [0x01ebf000, 0x01ebffff] PGTABLE > [ 0.000000] BRK [0x01ec0000, 0x01ec0fff] PGTABLE > [ 0.000000] BRK [0x01ec1000, 0x01ec1fff] PGTABLE > [ 0.000000] init_memory_mapping: [mem 0xc3fe00000-0xc3fffffff] // called from "memory_map_top_down(ISA_END_ADDRESS, end);" > [ 0.000000] [mem 0xc3fe00000-0xc3fffffff] page 1G // increase count of PG_LEVEL_1G in c00000000(48G)-c3fffffff(49G) one time > [ 0.000000] init_memory_mapping: [mem 0xc20000000-0xc3fdfffff] > [ 0.000000] [mem 0xc20000000-0xc3fdfffff] page 1G // increase count of PG_LEVEL_1G in c00000000(48G)-c3fffffff(49G) two time > [ 0.000000] init_memory_mapping: [mem 0x00100000-0xbf78ffff] > [ 0.000000] [mem 0x00100000-0x001fffff] page 4k > [ 0.000000] [mem 0x00200000-0x3fffffff] page 2M > [ 0.000000] [mem 0x40000000-0x7fffffff] page 1G > [ 0.000000] [mem 0x80000000-0xbf5fffff] page 2M > [ 0.000000] [mem 0xbf600000-0xbf78ffff] page 4k > [ 0.000000] init_memory_mapping: [mem 0x100000000-0xc1fffffff] > [ 0.000000] [mem 0x100000000-0xc1fffffff] page 1G // increase count of PG_LEVEL_1G in c00000000(48G)-c3fffffff(49G) three time > ... > [ 0.000000] DirectMap4k: 3648 kB > [ 0.000000] DirectMap2M: 2084864 kB > [ 0.000000] DirectMap1G: 50331648 kB > > euler-linux:~ # cat /proc/meminfo | grep DirectMap > DirectMap4k: 91712 kB > DirectMap2M: 4093952 kB > DirectMap1G: 48234496 kB > > > total DirectMap is 48234496 + 4093952 + 91712 = 52420160kb > 50331648 + 2084864 + 3648 = 52420160kb > total init_memory_mapping is 50323008kb > > 52420160kb - 50323008kb = 2097152kb = 2G > > However I haven't find a better way to fix it, any ideas? > > Thanks, > Xishi Qiu > > > . > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/