From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx204.postini.com [74.125.245.204]) by kanga.kvack.org (Postfix) with SMTP id CFB2A6B0005 for ; Wed, 10 Apr 2013 03:55:23 -0400 (EDT) Received: from /spool/local by e28smtp08.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 10 Apr 2013 13:19:53 +0530 Received: from d28relay05.in.ibm.com (d28relay05.in.ibm.com [9.184.220.62]) by d28dlp03.in.ibm.com (Postfix) with ESMTP id 65A141258052 for ; Wed, 10 Apr 2013 13:26:44 +0530 (IST) Received: from d28av02.in.ibm.com (d28av02.in.ibm.com [9.184.220.64]) by d28relay05.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r3A7tGCl7668076 for ; Wed, 10 Apr 2013 13:25:16 +0530 Received: from d28av02.in.ibm.com (loopback [127.0.0.1]) by d28av02.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r3A7tHpR020149 for ; Wed, 10 Apr 2013 17:55:18 +1000 From: "Aneesh Kumar K.V" Subject: Re: [PATCH -V5 06/25] powerpc: Reduce PTE table memory wastage In-Reply-To: <20130410071453.GB24786@concordia> References: <1365055083-31956-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <1365055083-31956-7-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <20130410071453.GB24786@concordia> Date: Wed, 10 Apr 2013 13:24:59 +0530 Message-ID: <87obdmom5o.fsf@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain Sender: owner-linux-mm@kvack.org List-ID: To: Michael Ellerman Cc: benh@kernel.crashing.org, paulus@samba.org, linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org Michael Ellerman writes: > On Thu, Apr 04, 2013 at 11:27:44AM +0530, Aneesh Kumar K.V wrote: >> From: "Aneesh Kumar K.V" >> >> We allocate one page for the last level of linux page table. With THP and >> large page size of 16MB, that would mean we are wasting large part >> of that page. To map 16MB area, we only need a PTE space of 2K with 64K >> page size. This patch reduce the space wastage by sharing the page >> allocated for the last level of linux page table with multiple pmd >> entries. We call these smaller chunks PTE page fragments and allocated >> page, PTE page. > > This is not compiling for me: > > arch/powerpc/mm/mmu_context_hash64.c:118:3: error: implicit declaration of function 'reset_page_mapcount' > can you share the .config ? I have the git tree at git://github.com/kvaneesh/linux.git ppc64-thp-7 -aneesh -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org